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  • 1970-1974  (37,150)
  • 1950-1954
  • 1935-1939
  • 1973  (37,150)
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  • 1970-1974  (37,150)
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Insectes sociaux 20 (1973), S. 1-20 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary Colonies ofHodotermes, Microhodotermes andAnacanthotermes have major and minor workers. InHodotermes, these develop independently from different larval stages; minor workers do not transform to major workers. For each major worker there are approximately 3.7 minor workers, and the actual sizes of the two worker castes can differ greatly from colony to colony. The first pigmented worker of incipient colonies is a minor worker of the 4th instar, but in more mature colonies the instars of the workers are later and variable. Large larvae, which can produce large workers, and small larvae with patchy pigmentation, which can produce minor workers, can also undergo stationary moults.
    Abstract: Zusammenfassung Kolonien vonHodotermes, Microhodotermes undAnacanthotermes, enthalten grosse und kleine Arbeiter. Im Falle vonHodotermes entwickeln sie sich unabhängig aus verschiedenen Larvenstadien; kleinere Arbeiter wandeln sich nicht in grössere um. Auf einen grossen Arbeiter entfallen etwa 3,7 kleine Arbeiter. Der tatsächliche Umfang der beiden Arbeiterkasten kann sehr von Kolonie zu Kolonie schwanken. Der erste pigmentierte Arbeiter in jungen Kolonien ist ein kleiner Arbeiter im 4. Larvenstadium, aber in älteren Kolonien setzen sich die Arbeiter aus älteren Larven mit unterschiedlicher Zahl von Häutungen zusammen. Grosse Larven, aus denen sich grosse Arbeiter entwickeln können, und kleine Larven mit fleckiger Pigmentierung, die sich zu kleinen Arbeitern differenzieren können, können auch stationäre Häutungen durchmachen.
    Notes: Résumé Les colonies deHodotermes, Microhodotermes et d'Anacanthotermes possèdent des grands et des petits ouvriers. ChezHodotermes, ceux-ci se développent indépendamment à partir de différents stades larvaires; les petits ouvriers ne se transforment pas en grands ouvriers. A chaque grand ouvrier correspond approximativement 3,7 petits ouvriers, et la taille réelle de ces deux castes d'ouvriers peut différer de façon importante d'une colonie à une autre. Le premier ouvrier pigmenté des colonies jeunes est un petit ouvrier du 4e stade, mais dans les, colonies plus âgées, les stades des ouvriers sont plus tardifs et variables. Les grosses larves pouvant produire de grands ouvriers, et les petites, avec des taches de pigmentation, des petits ouvriers, peuvent également subir des mues stationnaires.
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  • 2
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    Insectes sociaux 20 (1973), S. 71-85 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary Most works upon Termites hygrotactic reactions studied the effect of air humidity; this paper deals with water into the substrate as an attractive factor in Saintonge Termite. When water is presented to termites into plaster bars following a continuous pattern, no hygropreferendum gradient can be detected; termites seek to cluster in maximal humidity zone. The reaction is faster at higher temperature. When water is presented following a discontinuous pattern (separate plaster bars) termites prefer always maximum humidity. They are very able to discriminate humidities slightly different only. They avoid saturation hygrometry when a slightly inferior humidity is presented close to. This hygropreferendum is as clearly seen in the case of neutral substrates (plaster) than in the case of attractive ones (pieces of wood). Termites number play an important role in hygrotactic reaction. An isolated worker can choose maximal hygrometry but the more the Termites group is big, the more hygrotactic reaction is intense. It is more intense when water is into the substrate than into the air. Termites do not go directly towards wet zones, but try first all the possibilities following a chance schedule.
    Notes: Résumé Alors que la plupart des travaux sur la réaction hygrotaxique des Termites ont étudié l'effet de l'humidité de l'air, le présent travail est consacré à l'étude de l'eau du substrat, comme facteur attractif chez le Termite de Saintonge. Quand l'eau est présentée aux Termites sur des barres de plâtre en quantité croissante continue, aucun gradient pour l'hygropreferendum n'est mis en évidence: les Termites tendent à se grouper dans la zone d'humidité maximale. La réaction est plus rapide à température plus élevée. Quand l'eau est répartie de façon discontinue sur des morceaux de plâtre, les Termites manifestent toujours une préférence pour l'humidité maximale. Les Termites peuvent très bien discriminer des humidités peu différentes entre elles. Ils évitent de se fixer à l'humidité la plus grande lorsqu'on leur présente à proximité une humidité légèrement inférieure à cette dernière. Cet hygropreferendum est aussi bien marqué pour les substrats neutres (plâtre) que pour les bois attractifs. Le nombre de Termites joue un rôle important dans la réaction hygrotaxique. Un termite isolé peut choisir l'humidité maximale, mais plus le groupe est important plus la réaction hygrotaxique est intense. La réaction hygrotaxique est plus intense si l'eau est présentée sur le substrat que si elle parvient par l'atmosphère. Les Termites ne vont pas directement dans les zones humides mais essaient, avant, toutes les possibilités offertes.
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  • 3
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The analysis of the heart beat frequency variations induced by several stimuli in gregarious and solitarious adults of the Migratory Locust demonstrates: 1o The heart rate is significantly higher in animals exposed 80 mn to light (4,500 lux) than in Locusts kept in darkness. 2o Lighting induces, in dark adapted insects, a bradycardy with low light (45 lux) and a tachycardy with a higher intensity (4,500 lux). 3o In solitarious, when the light is switch off it appears a discrete tachycardy for all intensities; in the gregarious the reaction varies with light intensity. 4o Change in a continous air current without odor causes a bradycardy, at least in solitarious, but, when the odor of the some phase Locusts is added to the air current, it induces a very light tachycardy. 5o Comparison of the two phases data makes clear that the heart rate is higher and the cardiac reactivity to external stimulations is stronger in solitarious than in gregarious:a) deeper variations to light,b) shorter latency and higher heart responses to light and other stimulations,c) lower activation thresholds. 6o The results interpretation takes in account the nervous and endocrine regulation heart in Insects. 7o The problem of the biological significance of these heart responses is discussed: it could be one of the vegetative components of a «suprise reaction» possibly modulated by the significant value of the stimulus.
    Notes: Résumé L'analyse des variations de la fréquence cardiaque en réponse à diverses stimulations, chez des adultes grégaires et solitaires du Criquet migrateur, montre que: 1o Des criquets soumis à un éclairement prolongé assez intense (4 500 lux) présentent une fréquence cardiaque significativement plus élevée qu'à l'obscurité. 2o L'allumage d'une lampe entraîne, chez les insectes préalablement adaptés à l'obscurité, une variation de la fréquence cardiaque dont le sens dépend de l'intensité lumineuse (entre 45 et 4 500 lux). 3o La cessation de cette stimulation lumineuse induit chez les solitaires une légère tachycardie à tous les éclairements; chez les grégaires, au contraire, la réponse à l'extinction de la lumière varie en fonction de l'intensité. 4o Chez les solitaires tout au moins, l'arrêt momentané d'un faible courant d'air atteignant l'animal en permanence s'accompagne d'une bradycardie. Par ailleurs, l'odeur des congénères (appartenant à la même phase), quand elle s'ajoute au courant d'air, entraîne une très légère tachycardie. 5o La comparaison des résultats obtenus sur les animaux des deux phases montre que la fréquence cardiaque est plus élevée chez les solitaires que chez les grégaires. Les solitaires possèdent également une réactivité cardiaque plus importante aux stimulus externes, comme l'indiquent:a) une influence plus marquée des variations de l'éclairement ambiant,b) une latence plus brève et une ampleur généralement plus grande des réactions cardiaques à la lumière et à d'autres stimulus,c) l'existence de seuils d'activation plus bas. 6o Les résulats sont discutés en tenant compte des données récentes sur la régulation nerveuse et endocrine du rythme cardiaque chez les Insectes 7o Le problème de la signification biologique de ces réponses cardiaques est évoqué: on pourrait y voir l'une des composantes, végétatives, d'une «réaction de surprise» éventuellement modulée par la valeur signifiante du stimulus.
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  • 4
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    Insectes sociaux 20 (1973), S. 261-265 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary We present a probe to take well localized samples out of the nests of the groupFormica rufa.
    Abstract: Zusammenfassung Wir stellen eine Sonde vor zum Nehmen gut lokalisierter Müster aus den Nesthügein der GruppeFormica rufa.
    Notes: Résumé Nous présentons une sonde pour la prise d'échantillons bien localisés dans les nids du groupeFormica rufa.
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  • 5
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    Insectes sociaux 20 (1973), S. 323-331 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Les ouvrières deMyrmecia froggatti Forel et deM. varians Mayr présentent un monomorphisme avec une faible variabilité de la taille, tandis que celles deM. simillima montrent un dimorphisme avec une considérable variation de la taille. Les valeurs des coefficients de variabilité calculés pour quatre caractères fournissent une bonne mesure de la variation spécifique de la taille. Les histogrammes de fréquence du rapport longueur/largeur de la tête sont unimodaux pour une colonie deM. froggatti et trois colonies deM. varians et bimodaux pour cinq colonies deM. simillima.
    Notes: Summary Myrmecia froggatti Forel andM. varians Mayr workers show monomorphism with limited size variability, while those ofM. simillima exhibit biphasic monomorphism with considerable size variation. Coefficient of variability values calculated for four characters provided a good measure of species size variation. Frequency histograms of head length against head width were distinetly unimodal in one colony ofM. froggatti and three colonies ofM. varians, and bimodal in the five colonies ofM. simillima.
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  • 6
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    Insectes sociaux 20 (1973), S. 333-342 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé On a étudié la relation entre les mues larvaies et les mues à soldat dans des groupes de pseudergates formés par différents nombres d'individus: de 2 jusqu'à 25. Dans tous les groupes, il y avait un couple royal et des soldats manquaient continuellement. On a fait deux séries d'expériences: dans une série, le nombre d'insectes décroissait, les pseudergates muées ayant été éloignées; dans l'autre série, le nombre était constant, les animaux morts ou mués ayant été remplacés par des pseudergates marquées. Dans les groupes formés par 2 ou 3 pseudergates, les mues à soldat sont très peu fréquentes; elles atteignent une valuer intermédiaire dans les groupes de 5–12 pseudergates et des valeurs plus élevées dans les groupes de 13–25 individus. Des différences assez nettes et relativement constantes séparent les pourcentages des soldats différenciés dans les trois conditions indiquées. Le nombre des pseudergates joue donc un rôle dans la détermination des soldats, moins important toutefois que celui qui est joué par le couple royal. On discute la possibilité que les pseudergates exercent leur influence stimulatrice par l'intermédiaire du couple royal ou directement sur les individus de leur même stade.
    Abstract: Riassunto E' stato studiato il rapporto tra mute larvali e mute a soldato in gruppi di pseudergati costituiti con numeri diversi di esemplari: da 2 fino a 25. Tutti i gruppi comprendevano una coppia di reali e mancavano continuamente di soldati. Nei gruppi formati con 2 o 3 pseudergati, le mute a soldato avvengono con frequenze assai basse; hanno valori intermedi nei gruppi di 5–12 pseudergati e più elevati in quelli di 13–25 esemplari. Differenze abbastanza nette e relativamente costanti separano le percentuali di soldati differenziati nelle tre condizioni indicate. Il numero delle pseudergati ha dunque un ruolo nella determinazione dei soldati, seppure molto minore rispetto a quello svolto dai reali. Viene discussa la possibilità che le pseudergati esercitino la loro azione stimolatrice tramite la coppia reale, o direttamente sulle compagne di gruppo.
    Notes: Summary The differentiation of pseudergates into soldiers was investigated in soldierless experimental groups formed by a royal pair of supplementary reproductives and by different numbers of pseudergates in a range from 2 to 25. Two series of experiments were carried out: one with decreasing numbers of insects per group, since the moulted pseudergates were removed by each group, the other with a constant number, since the moulted or dead insects were replaced with marked pseudergates. Frequences of moults into soldiers were very low in small groups (2–3 pseudergates); they were intermediate in groups of 5 to 12 pseudergates, and were higher in the largher groups of 13 to 25 pseudergates. Thus, the moults into soldiers appear to by influenced by the number of pseudergates; therefore these play a role in stimulating the differentiation into soldiers, althrough at a much lower degree than the royal pair. The effect of pseudergates, direct or indirect, is discussed.
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  • 7
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    Insectes sociaux 20 (1973), S. 391-393 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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  • 8
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    Insectes sociaux 20 (1973), S. 41-64 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The study ofOrphania scutata was undertaken through classical dissection methods. Aspect and arrangement of brain and ganglia, as well as setting and direction of nerves emergence, have been studied. In male as well as female, brain, thoracic ganglia and stomatogastric system show the same disposition. Among the ganglia of the ventral nerve cord, the last one or genital ganglion presents modifications in male as well as in female.
    Notes: Résumé L'étude anatomique du système nerveux central et stomatogastrique d'Orphania scutata fut entreprise par les méthodes classiques de dissection. L'aspect et la disposition des masses cérébrales et ganglionnaires sont étudiés ainsi que la disposition et le trajet des nerfs qui en sont issus. Chez le mâle comme chez la femelle, le cerveau, les ganglions thoraciques et le système stomatogastrique présentent la même disposition. Seul, parmi les ganglions de la chaîne nerveuse ventrale abdominale, le dernier ganglion, ou ganglion génital, résulte de la fusion des neuromères 8–9–10–11, et présente des particularités liées au sexe.
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  • 9
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    Insectes sociaux 20 (1973), S. 103-107 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The widely distributed palearctic speciesCrossocerus (Cuphopterus) dimidiatus exhibits remarkable social behaviour. In one case at least six females, in another three females shared the same hole in a house wall. Great differences in the activity of the females can be interpreted as evidence of a division of labor among these females. One of three females was catching flies for provisioning the nest, while the two others were staying mostly «at home», at least temporary guarding the nest. This is the second record of division of labor in Sphecoidea. There were no great morphological differences among the females. The nest could not be examined, but most probably the wasps were sharing really a common nest and not only a common entrance.
    Notes: Zusammenfassung Die weit verbreitete paläarktische ArtCrossocerus (Cuphopterus) dimidiatus zeigt ein bemerkenswertes soziales Verhalten. Ein Loch in einer Hauswand wurde in einem Jahr von mindestens sechs, im nächsten von drei Weibchen gemeinsam benutzt. Große Aktivitätsunterschiede der Weibchen lassen sich als Zeichen einer Arbeitsteilung deuten. Von drei Weibchen trug eines Fliegen ein, während die beiden anderen im Nest blieben und zumindest zeitweilig Wächterdienst leisteten. Es ist dies der zweite Nachweis von Arbeitsteilung bei Sphecoidea. Die Weibchen unterschieden sich körperlich nur gering voneinander. Das Nest selbst konnte nicht untersucht werden, doch liegt die Annahme nahe, daß tatsächlich ein gemeinsames Nest und nicht nur ein gemeinsamer Eingang benutzt wurde.
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  • 10
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    Insectes sociaux 20 (1973), S. 109-123 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé 1. La relation entre le nombre de récolteuses et de nourrices, dans un espace vital limité, donne une augmentation du nombre et poids comparable aux cultures à faible densité dans les nids plans. Parmi les récolteuses, il y a un nombre petit mais constant de nourrices. 2. Huit cages d'élevage, longueur 1–8 cm (6 mm diam.), ne donnent pas d'augmentation de la population moyenne des butineuses dans la seconde période de comptage de trois semaines. Il n'est pas observé de différences remarquables entre traitements ou d'un jour à l'autre. Une indication de l'effet de densité est montrée par les deux plus petites cultures, autrement le poids moyen du couvain régressant avec le nombre d' ♀ à l'intérieur corrobore l'absence d'effet de densité. 3. Huit cages d'élevage, longueur 0,5–4 cm (4 mm diam.), ne donnent pas de couvain à développement rapide, mais le nombre de larves résiduelles régresse avec l'espace vital relatif disponible. 4. Un nouvel essai, 0,5–4 cm (4 mm diam.), suggère un changement du groupe d' ♀ avec un nombre constant de larves rèsiduelles, sauf dans les deux plus petites cultures. 5. Le changement d'un paquet d' ♀ n'a pas ètè observè avec succès car les ♀ ont maintenant un fort groupement. Tout le temps, correspondant cependant à l'état de groupement étroit de l'expérience précédente. Une chute constante des «individus d'intérieur», 10 ♀, a été observée. 6. Des pertes de couvain dans les cultures à haute densité semblent vraisemblablement dues à l'agression des ♀. Deux larves mâchonnées ont été vues. 7. L'interaction des effets de la reine et de la haute densité produit und moindre gain de poids pour les grandes larves hibernantes, bien qu'une forte densité seule a de considérables effets inhibiteurs. 8. La présence de la reine et une haute densité ont un effet moindre, mais certain, sur les petites larves hibernantes. Les pertes sont plus grandes et les gains de poids plus petits quand une reine est présente à grande densité. Elle occupe un volume physique équivalent à 3 ♀ et une présence «comportementale» du même nombre et ces dernières sont exclues quand l'espace est limitè.
    Notes: Summary 1. Interaction of increasing forager numbers with nurses in a limited living space gave numbers and weight increases comparable to low density cultures in plane nests. The foraging population included a small but constant number of nurses. 2. Eight living volumes, length 1–8 cm (6 mm diam.) gave no increase of mean foraging population in the 2nd of 2 three-week periods of counting. No noticeable difference, between treatments, or from day to day was shown. An indication of density effect was shown by the two smallest cultures, otherwise the mean brood weight regressing with inside worker number supported a lack of density effect. 3. Eight living volumes, length 0.5–4 cm (4 mm diam.) gave no rapid brood but residual larval numbers regressed with relative available living space. 4. A repeat trial, 0.5–4 cm (4 mm diam.) suggested a change of worker packing with a constant number of residual larvae except in the two smallest cultures. 5. Change of packing was not successfully observed as workers maintained a tight packing pattern throughout, corresponding however to the tightly packed stage of the previous experiment. A constant fall of insiders, 10 workers/cm length was observed. 6. Brood loss in high density cultures seems likely to be caused by worker aggression. Two chewed-up larvae were observed. 7. Interaction of queen effect and high density, caused least weight gain for large, hibernated larvae although high density alone had considerable inhibitory effects. 8. Queen presence and high density had a lesser but definite effect on small hibernated larvae. Losses were greater and weight gains smaller when a queen was present at high density. She has a physical volume equivalent to 3 workers and a «behavioural» presence of the same number and these latter were excluded when space was limited.
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  • 11
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    Insectes sociaux 20 (1973), S. 133-144 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary This paper is presented as a preliminary inquiring into the leaf-cutting behaviour of the fungus-antAtta sexdens rubropilosa. We have measured the amount of daily leaf-cutting in five ant-nests, the amount of leaf-cutting by periods of 12 hours, and the amount of leaf-cutting of different leaf species. We have found great differences of leaf-cutting between ant-nests and irregular daily differences in each nest. We were unable to find a nycthemeral rhythm independent from environmental conditions, or a preference towards a determined leaf species. Introducing obstacles on the way of leaf-carrying workers showed us a great adaptability of this behaviour, and its subordination to the possibility of introduction of leaf-pieces into the nest.
    Notes: Résumé Comme démarche préliminaire à une étude expérimentale du comportement del'Atta sexdens rubropilosa, nous avons mesuré la quantité de découpage journalier des feuilles fournies à cinq colonies différentes, la quantité de découpage par période de douze heures et, la quantité de découpage de différents végétaux. D'autre part, nous avons introduit différents obstacles dans le circuit qui va des feuilles à l'intérieur du nid. Quant au découpage, nous avons décelé de grosses différences entre les colonies, mais des différences journalières dans chaque colonie. Nous n'avons pu trouver ni un rythme nyctéméral indépendant des conditions extérieures, ni une préférence constante pour un des végétaux fournis. L'introduction des obstacles montre la grande élasticité de ce comportement, aussi bien que sa subordination à la possibilité de livraison des découpures dans l'intérieur du nid.
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  • 12
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    Pure and applied geophysics 109 (1973), S. 1738-1742 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Summary Free radial vibration of a non-homogeneous circular plate of variable thickness has been studied. The thickness at a distancer from the axis through the centre of the plate perpendicular to the middle surface is chosen to be a function ofr. The problem has been solved for a disc with a central hole and also for one having no central hole.
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  • 13
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    Pure and applied geophysics 109 (1973), S. 1718-1727 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Summary Earthquake parameters for the forty aftershocks of the main Koyna earthquake of 10 December, 1967, have been determined. Depths of the foci of the earthquakes have been found to vary between 2 to 17 km. The velocities for the phasesP g ,P *,P n have been observed to be 5.78±0.00, 6.58±0.04, 8.19±0.02 km/sec, and forS g ,S *,S n to be 3.42±0.00, 3.92±0.01 and 4.62±0.01 km/sec respectively. A two-layered crustal model has been interpreted for the Peninsular shield with the average thickness of the granitic layer as 20 km and that for the basaltic layer as 18.7 km. A plot of the epicenters suggests a NNE to SSW orientation of the fault.
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    Pure and applied geophysics 109 (1973), S. 1752-1761 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Summary The spectral amplitude fields of seismic waves produced by directed (non-spherical) and undirected (spherical) explosive sources are described. The following four cases were investigated: a spherical source located at the bottom of a borehole, a spherical, a hemi-spherical, and a conical source placed at the wall of a trench. The geophones measuring theX, Y andZ components of the seismic waves produced were situated on the Earth's surface within a circle round the epicentre of each source. The records were Fourier analyzed and amplitude spectra were used to establish spectral amplitude fields of these components. Amplitude and frequency variations of the seismic wave patterns are discussed in the paper.
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    Pure and applied geophysics 109 (1973), S. 1796-1809 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Summary The electric and magnetic field variations over an arbitrarily sloping ocean floor are represented in series of Bessel functions forH-polarized uniform plane wave excitation. Calculation of the spatial variations of electric eurrents and apparent resistivity near a coastline will determine the usefulness of the magnetotelluric method in this application.
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  • 16
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    Pure and applied geophysics 109 (1973), S. 1781-1788 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Summary Forced hydromagnetic oscillations in the outer core due to stress at its top are studied by means of a simple linear theoretical model originally proposed byHide [1] for the free oscillation studies. Both the magnetic and the inertial modes are excited. The expressions for the velocity, magnetic and vorticity fields are presented for a variety of stresses. They depend upon the wave number and frequency. In a numerical example wherein the stress varies periodically both in the space and the time, the amplitude of the induced magnetic field is found to be significant for reasonable values of various parameters.
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    Pure and applied geophysics 109 (1973), S. 1862-1869 
    ISSN: 1420-9136
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    Description / Table of Contents: Résumé Dans le présent travail on a procédé à une expérience pour déterminer les variations temporelles des principaux paramètres aéronomiques en utilisant des données expérimentales par la méthode A3 de mesure de l'absorption ionosphérique, la méthode ‘phase-altitude’ et des données satellites aux rayons X durs. On a examiné les variations diurnes et les variations temporelles lors de SID effet durant le 21 Août 1969, de la densité électroniqueN(t) et du coefficient de récombinaison α′(t). On a montré que lors de SID effet α′(t) s'accroît.
    Notes: Summary In this paper an attempt is made to define the time variations of theD-region main aeronomical parameters under non-equilibrium conditions by using experimental data by the A3 method, phase-height method and satellite data for the short-wave X-radiation. The SID effect of day-time and time variations of 21 August 1969 electron concentrationN(t) and recombination coefficient α′(t) are investigated. It is shown that during SID effect α′(t) increases.
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    Pure and applied geophysics 102 (1973), S. 67-72 
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    Notes: Summary A new method of interpreting the gravity and magnetic anomalies is introduced with special reference to the magnetic anomalies of a horizontal cylinder. The method consists of calculating the functions of the anomaly and its distance from an arbitrary point. These form a simple linear equation with coefficients related to the parameters defining the body. Since each observation forms a separate linear equation, the required normal equations are formed by the method of least squares and solved for the coefficients and hence for the various parameters defining the target. The discussion here is confined to the vertical magnetic anomalies. The application of the method to horizontal and total field anomalies of two dimensional bodies is also outlined.
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    Pure and applied geophysics 102 (1973), S. 29-36 
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    Notes: Summary This paper consists of two parts. In the first part, the existence of Love waves in non-homogeneous and transversely-isotropic elastic layer over-lying a semi-infinite isotropic elastic solid has been investigated. The frequency equation for such waves has been derived. Numerical calculations giving the velocity of such waves has been made for different layer thicknesses. In the second part, a characteristic frequency equation has been calculated considering the lower boundary of the layer to be rigid. A numerical calculations has been made in this case also to represent the variation of wave number with velocity for different mode number.
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    Pure and applied geophysics 102 (1973), S. 78-90 
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    Notes: Summary In this paper we discuss the propagation of Rayleigh type waves in an elastic medium with two horizontal layers overlying a semi-infinite elastic medium above which lies a liquid layer. The upper solid layer is taken to be transversally isotropic the elastic properties of which are given by the strain energy volume density function $$2 W = A(e_{xx^2 } + e_{yy^2 } ) + Ce_{xx^2 } + 2 F(e_{xx} + e_{yy} ) e_{zz} + 2(A - 2 N) e_{xx } e_{yy} + L(e_{yz^2 } + e_{zx^2 } ) + Ne_{xy^2 } .$$ The liquid layer is assumed to be homogeneous. The equation giving the wave velocity as a function of wave number is determined as a determinant of eleventh order which has further been simplified for different particular cases. The numerical solution of the problem will be conveyed in the next paper.
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    Pure and applied geophysics 102 (1973), S. 105-119 
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    Notes: Summary The rotating nature of telluric field is simulated in an electrolytic model tank. Variations of this rotating field due to the presence of a few two and three dimensional geological models, simulated in the tank, are studied. The telluric ellipses, recorded on a C.R.O. Screen, are found to be useful for qualitative and quantitative interpretation of the non-linearly polarised telluric field data. Relative usefulnesses of the various parameters, e.g., (i)M=ratio of the semimajor and semiminor axis, (ii)K = square root of normalized surface areas, (iii) λ = linear eccentricity (✓(a 2/b 2-1) and (iv)e = conventional eccentricity ((✓1-b 2/a 2)), of a telluric ellipse are tested. Linear eccentricity appears to be the most sensitive parameter. Methods for determining depth and horizontal extent of a structure from a telluric map are suggested. Near surface inhomogeneities, as revealed from the experiment are unlikely to affect the telluric map due to a basement structure.
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    Pure and applied geophysics 102 (1973), S. 134-147 
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    Notes: Summary The MT method is applied to the study of a buried graben in the western Canadian sedimentary basin. Tensor analysis and two dimensional numerical modeling techniques were applied as an aid to the interpretation. The results obtained indicate the presence of a buried geoelectric structure and the need of interpreting MT apparent resistivity curves in terms of the regional geology and major structural features which are not necessarily one dimensional.
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    Pure and applied geophysics 103 (1973), S. 282-289 
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    Notes: Summary Origin ofP waves detected earlier in microseisms of very quiet locations in the USSR is discussed in detail. It appears that the most pronounced sources ofP waves are tropical cyclones over the Pacific. The amplitude of the force in the source for a medium power typhoon is found to be of the order of 1016 dynes. The effective source area is estimated as 104–105 km2 approximately. The shape of the amplitude spectrum ofP wave corrected for the absorption in the mantle does not contradict with the standing wave theory of microseisms generation. Results of observations at various epicentral distances give strong evidences of the predominant attenuation of the fundamental Rayleigh mode as compared with higher Rayleigh modes andP waves in the frequency band of 0.3–0.15 cps.
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    Pure and applied geophysics 103 (1973), S. 266-273 
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    Notes: Summary Experiments have been made to determine whether a significant amount of microseism energy in the open ocean can be carried in organ-pipe π waveguide modes. A three-component seismometer in a spherical aluminum container was balanced to float freely at midwater depth; a similar instrument was dropped on the ocean bottom. Simultaneous records from the two instruments were analyzed for peaks in coherence of their power spectra. Results indicate a substantial energy in π modes in the ocean area of the observation, though the peak power appears in an unidentified mode with large horizontal motion of the water. Measurements at the same area, but widely separated in time, indicate that the frequencies of microseism peaks and the general shape of the microseism spectrum are characteristic of the geographicallocation, in agreement with the conclusion of Monakhov. The microseisms are characterized as motion in a wave guide that is excited by a non-white forcing function.
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    Pure and applied geophysics 103 (1973), S. 332-346 
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    Notes: Summary In this paper two methods for analysing in real time (or on line) microseisms recorded near a coast, with the aim to deduce their fundamental periods and evolution, are presented. Firstly, the autocorrelation of microseisms as a random signal is derived, whereas the second method consisting in a frequential filtering is more extensively used. The application of these methods is also made for simultaneously recorded microseisms in Genoa and in Vesima-Arenzano (station placed just on shore-line). The results show that in Genoa the peak amplitude ratio between secondary and primary microseisms is varying in the range of 3–28, whereas in Vesima this ratio is about the unity. This behaviour is explained on account of the different breaking zones for the two stations.
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    Pure and applied geophysics 103 (1973), S. 347-347 
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    Pure and applied geophysics 103 (1973), S. 405-405 
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    Pure and applied geophysics 104 (1973), S. 460-466 
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    Notes: Summary Proceeding from the equations of electromagnetism (Maxwell) and those of mechanical motions, this investigation has been carried in a layered media, comprising of a liquid and a solid (Fener type) layers to determine the mechanical deformation. It is found that the disturbances owing to the coupling effect of the transversely acting magnetic field and the tangential force along the inference, are predominantly transient in character for both ranges of time, but being damped more in case of larger values.
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    Pure and applied geophysics 104 (1973), S. 473-483 
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    Notes: Summary In this paper slow steady motion of fluid, through the annular space between two porous co-axial elliptic cylinders has been studied. There is a suction or injection perpendicular to the walls of the tube; the amount of suction (or injection) per unit length through the outer wall is equal to the amount of injection (or suction) through the inner wall. The pressure gradient along the length of the cylinder is constant. The cylinders are assumed to be large and the distance between them is small. The amount of injection or suction is assumed to be small. Method of perturbation is applied to obtain the velocity distribution.
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    Pure and applied geophysics 104 (1973), S. 513-522 
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    Notes: Summary In this paper, steady state thermoelastic stresses in an elastic layer when there is a heat flux at one of its bounding planes, have been determined by the method of differential operators and Mittag-Leffler theorem.
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    Pure and applied geophysics 104 (1973), S. 566-573 
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    Notes: Summary Solution of boundary layer equations in a plasma in the presence of a magnetic field perpendicular to the direction of the flow have been deduced whenP r =1,c p =constant and the wall is thermally insulated. The magnetic fieldH has a dependence onx of the formD/x m . The velocity in the main stream varies asx 1–2m . The solutions have been discussed for two particular values ofm representing two physical flows.
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    Pure and applied geophysics 104 (1973), S. 582-593 
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    Notes: Summary An initial value investigation is made of the transient development of dispersive long waves on a homogeneous rotating shallow ocean generated by an arbitrary steady or oscillatory wind stress disturbances. The significant effect of the rotation on these long waves is examined. The solution of the problem related to physically realistic wind stress distributions is obtained with physical implications. The principal features of the wave motions are explored. In place of complicated Green's function technique, the problem is solved by the generalized Fourier transform and the Laplace transform methods combined with the asymptotic techniques. The method of solution used is simple, elegant and straightforward.
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    Pure and applied geophysics 105 (1973), S. 669-695 
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    Notes: Summary Based on a system of structurally simple postulations the kinematics of mantle convection is derived. With regard to the strain-stress relations valid in the mantle and the energy source of the convection the theory is without any presumptions. In compliance with recent hydrodynamic investigations the flow is introduced rather as roll currents than as a hexagonal cell pattern. From the feasible types of current a theoretical topography is derived which is in quantitative agreement with the observed one. Also the distribution of the seismic discontinuities substantiates the validity of the expression. Finally, some suggestions are given for a hydrodynamic theory of mantle convection. This paper contains that part of the theory which is necessary for testing the calculations, while the relationship of the theory to other geological and geophysical problems are dealt with by the author [26]2).
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    Pure and applied geophysics 105 (1973), S. 770-780 
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    Notes: Summary The time of occurrence and the magnitude of the largest aftershock in relation to the main shock have been studied for India and its neighbourhood based on the USCGS data during the years 1963–1971. It is found that the largest aftershock occurs within 2 hours after the main shock in about 50% of the cases and frequency of occurrencen(t) of the largest aftershocks decreases hyper-bolically with the intervalt after the main event and could be represented by a law of the formn(t)=At −h whereA andh are constants. The probability of occurrence of the largest aftershock within 2 hours of the main shock is found to be higher over island are regions of the world. The difference (M 0–M 1) of the magnitude of the largest aftershockM 1 to that of the main shockM 0 as a measure of aftershock activity does not show any marked regional variation over India and its neighbourhood, as was reported by Mogifor Japan. Examination of the values ofM 1/M 0 and the constantb in Gutenberg-Richter's frequency magnitude relationship reveals a range of variation in both; high values ofM 1/M 0 have been found to be associated with high values ofb in many tectonic earthquakes and thus not, restricted to reservoir associated seismic activity.
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    Pure and applied geophysics 105 (1973), S. 816-824 
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    Notes: Summary In the case of low frequency motions in an elastic continuum, first-order perturbation theory can be used to estimate the effect of real-world deviations from the ideal model. Although the effects are often small, some interesting results can be found fairly easily. In spite of the simplicity in the structure of the formalism, nontrivial applications lead to remarkably complicated results.
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    Pure and applied geophysics 105 (1973), S. 836-846 
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    Notes: Summary The telluric field anomalies over a faulted basement are computed along profiles, perpendicular to the strike of the fault planes. Schwarz-Christoffel transformations, numerical method of solving non-linear differential equations and graphical crossplotting are used to obtain the solution of the boundary value problem. Computed anomaly curves reveal that (i) quantitative estimation regarding the width of the structure and throw of the faulting can be made from the telluric and its horizontal derivative maximal by graphical crossplotting, (ii) degree of resolution decreases with the increasing depth of the structure, (iii) the effects of a faulted basement (rectangular ridge) and those of a folded basement (triangularrridge) (Roy andNaidu [2]) are similar to a considerable extent.
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    Pure and applied geophysics 105 (1973), S. 864-868 
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    Notes: Summary The equation for density perturbation induced by plane hydromagnetic waves (responsible for geomagnetic secular variation) has been derived based on β-plane formulation. It is deduced that for the usual physical properties of the earth's core such a density perturbation would be small and would not be, in the main, responsible for the recently discovered correlation between gravitation and geomagnetic potentials.
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    Pure and applied geophysics 105 (1973), S. 879-889 
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    Pure and applied geophysics 105 (1973), S. 890-899 
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    Notes: Summary Indirect observational estimates are obtained of the covariance of diabatic heating and temperature at 850 mb, and of the implied value of the Newtonian cooling coefficient, for winter and summer mean conditions over the Northern Hemisphere. Combining the Newtonian approximation for heating and the Austausch approximation for the horizontal transient eddy heat transport we obtain a simple formula for the variance of the temperature at 850 mb in terms of the climatological mean temperature field at that level. Hemispheric fields computed from this formula seem to be an acceptable first approximation to the observations
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    Pure and applied geophysics 106-108 (1973), S. 1000-1009 
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    Pure and applied geophysics 106-108 (1973), S. 1010-1017 
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    Notes: Abstract The spatial and temporal distribution of total ozone over India and its vertical distribution in theatmosphere during 1964–1969 was studied using Dobson spectrophotometer data at a network of six stations in India, Srinagar (34°N), New Delhi (28°N), Varanasi (24°N), Ahmedabad (23°N), Dum Dum (22°N), and Kodaikanal (10°N). The annual and seasonal variations show a clear phase-shift in the occurrence of the ozone maxima and minima as one proceeds from higher to lower latitudes in the tropics. In the northern stations (north of 25°N) the increase in total ozone during the course of the annual variation is caused by the fractional increase in all layers from the ground to 28 km, the main contribution coming from 10–24 km. Above 28 km the concentration changes roughly in accordance with photochemical production. In lower latitudes (south of 25°N) an increase in total ozone amount during the annual cycle is caused by a gradual increase in all the layers from the ground to 36 km above which the variation is negligible.
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    Pure and applied geophysics 106-108 (1973), S. 1036-1040 
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    Notes: Abstract Aboard commercial airliners twenty registrations of the ozone concentration of the upper troposphere were carried out within a period of 14 months between Europe and South Africa. Nearly each of these meridional ozone profiles shows an approximately constant ozone content between 25°S and 25°N with a pronounced seasonal variation. Most of these profiles show two marked peaks of the ozone concentration at about 30°N and between 40° and 45°N. Though the number of these registrations is not sufficient for statistical computations, the first results confirm the meridional ozone distribution, which was expected from studies with ozone-radiosonde soundings. Moreover a strong asymmetry of the northern and southern hemisphere is confirmed by these ozone measurements.
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    Pure and applied geophysics 106-108 (1973), S. 1058-1073 
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    Notes: Abstract Evaluations of radiosonde soundings over North America and Europe, measurements aboard commercial airlines, and permanent ozone registrations at nineteen ground-based stations between Tromsö, Norway, and Hermanus, South Africa, yield three belts of higher ozone intrusion from the stratosphera and maximum values of the annual means at about 30°N, at between 40°–45°N and at about 60°N. A marked decrease of the annual mean values of the tropospheric ozone is detected towards the equator and the pole, respectively. In the northen hemisphere the maximum of the annual cycle of the tropospheric ozone concentration occurs in spring at high latitudes and in summer at mid-latitudes. For the tropical region from 30°S to 30°N a strong asymmetry of the northern and southern hemisphere occurs. This fact is discussed in detail. The higher troposphere of the tropics seems to be a wellmixed reservoir and mainly supplied with ozone from the tropopause gap region in the northern hemisphere. The ozone distribution in the lower troposphere of the whole tropics seems to be controlled by the up and down movements of the Hadley cell. The features of large-scale and seasonal variation of tropospheric ozone are discussed in connection with the ozone circulation in the stratosphere, the dynamic processes near the tropopause and the destruction rate at the earth's surface.
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    Pure and applied geophysics 106-108 (1973), S. 1091-1096 
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    Pure and applied geophysics 106-108 (1973), S. 1139-1150 
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    Notes: Summary Observations of the vertical ozone distribution over Arosa, Switzerland, have been carried out routinely since 1956 (with one two-year gap). Long-term trends of ozone concentration at different levels indicated by this series are discussed in the light of the results obtained from five years of parallel measurements with two Dobson spectrophotometers. Further substantiation of the suggested correlation between ozone concentration in the upper stratosphere and solar activity (with a two- to three-year lag of ozone against sun-spot numbers) is needed because no full agreement was obtained from the two instruments with respect to the secular variation at those top levels.
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    Pure and applied geophysics 106-108 (1973), S. 1180-1191 
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    Notes: Abstract The latitudinal and temporal variations in the vertical profiles of ozone over the Indian subcontinent are discussed. In the equatorial atmosphere represented by Trivandrum (8°N) and Poona (18°N), while tropospheric ozone shows marked seasonal variations, the basic pattern of the vertical distribution of ozone in the stratosphere remains practically unchanged throughout the year, with a maximum at about 28 to 26 km and a minimum just below the tropopause. The maximum total ozone occurs over Trivandrum in the summer monsoon season and the latitudinal anomaly observed over the Indian monsoon area at this time is explained as arising from the horizontal transport of ozone-rich stratospheric air from over the thermal equator to the southern regions. In the higher latitudes represented by New Delhi (28°N), the maximum occurs at 23 km. Delhi, which lies in the temperate regime in winter, shows marked day-to-day variations in association with western disturbances and the strong westerly jet stream that lies over north and central India at this time. Although the basic pattern of the vertical distribution of ozone in the equatorial atmosphere is generally the same in all seasons, significant though small changes occur in the lower stratosphere and in the troposphere. There are small perturbations in the ozone and temperature structures, distinct ozone maxima being always associated with temperature inversions. There are also large perturbances not related to temperature, ozone-depleted regions normally reflecting a stratification of either destructive processes or materials such as dust layers or clouds at these levels. Particularly interesting are the upper tropospheric levels just below the tropopause where the ozone concentration is consistently the smallest, in all seasons and at all places where soundings have been made in India.
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    Pure and applied geophysics 106-108 (1973), S. 1208-1218 
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    Notes: Summary The correlation matrix for the vertical ozone distribution and the temperature-ozone cross-correlation matrix, which was calculated from ozone soundings made over Berlin between 1967 and 1970, the statistical structure of the vertical ozone profile (correlation coefficients, average profiles, average standard deviation, relative variability) was derived for the three ozone seasons. The partial ozone pressure does not at all heights follow a normal distribution (e. g. at tropopause level). Generally, the correlation between tropospheric and stratospheric ozone is rather poor. In some layers the highest correlation coefficients, i.e. −0.3 and +0.4, occur in autumn (October to December) and in winter and spring (January to April). The correlation between the ozone amounts of various stratospheric layers is distinct in autumn, less distinct in summer (May to September) and entirely missing from January to April. Conspicuous cross-correlations between temperature and ozone have been found for all three seasons. a) With a negative correlation between tropospheric temperature and middle tropospheric to middle stratospheric ozone (maximum up to −0.8); b) with a rather strong positive correlation between the ozone amount and the temperature in the lower stratosphere (maximum up to +0.84); c) with a positive correlation between the ozone amount of the middle stratosphere and the temperature of the middle stratosphere (maximum up to +0.8). The highest correlation coefficients occur in autumn.
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    Pure and applied geophysics 106-108 (1973), S. 1254-1263 
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    Notes: Abstract The ultraviolet Earth radiance data from the backscatter ultraviolet experiment on Nimbus 4 have been inverted to infer ozone profiles using a single Rayleigh scattering model. Two methods of solution give essentially the same results. Comparison of these profiles with simultaneous rocket sounding data shows satisfactory agreement at low and middle latitudes. Vertical cross-sections of ozone mixing ratio along the orbital tracks indicate that while the gross characteristics of the ozone field above 10 mb are under photochemical control, the influence of atmospheric motions can be found up to the 4 mb level.
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    Pure and applied geophysics 106-108 (1973), S. 1290-1301 
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    Notes: Abstract For four years measurements of solar radiation have been made with an instrument which observes the sky radiance in two spectral regions. The measured incident radiation is independent of the direction. Formulas are derived which allow to conclude the daily sun intensity in one region, knowing the measured intensity in the other region. The effect of ozone is noticeable in the difference between the measured and computed values in an ozone-absorbing region. The optical behaviour of the atmosphere can be defined by parameterization of extinction effects. From this one can conclude the intensity of any other spectral region and thus define selective influences of other absorbing gases like air-polluting constituents.
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    Pure and applied geophysics 106-108 (1973), S. 1312-1317 
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    Pure and applied geophysics 106-108 (1973), S. 1325-1335 
    ISSN: 1420-9136
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    Topics: Geosciences , Physics
    Notes: Abstract Values of the mixing ratio by volume of stratospheric NO2 and CH4 deduced from infrared spectra taken by means of balloon-borne spectrometers are presented. Possible evidence for the presence of formaldehyde in the stratosphere is also given.
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    Pure and applied geophysics 106-108 (1973), S. 1336-1340 
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    Notes: Summary A brief report on the instrumentation for observations, at the ground, in the 9 μ to 11.6 μ spectral region, in the absorption of solar radiation through the terrestrial atmosphere and of the results thus obtained for the H2O, O3 and HNO3 molecules. The observations have been made at Montlouis, in the south of France, at 1650 m above sea-level. Here the pollution of the atmosphere is very low because there is no industry and very little local domestic activity. The chief aim ofM. Dionne [1], who is mainly responsible for this work, was to study the weak absorption of the terrestrial atmosphere around and beyond 10 μ, so observation had to be made with large air masses. For if there were excess water vapour the very weak lines might disappear through the background, owing to the water vapour itself; hence the need to observe during cold weather. Great air masses and cold weather can be obtained only on fine winter days, at about sunset. The configuration of Montlouis makes it difficult to observe at sunrise, so the time of observation was very limited.
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    Pure and applied geophysics 106-108 (1973), S. 1352-1360 
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    Topics: Geosciences , Physics
    Notes: Abstract Stratospheric profiles of CH4 and H2 over eastern Texas have been derived up to 31 km altitude from air samples collected aboard a balloon and analyzed by gas chromatography. For H2, contamination during flight and measurement presented a problem which has been resolved only recently. The earlier profiles require corrections which are rather large for the highest altitudes. The three profiles indicate an increase of the H2 concentration in the lower stratosphere from about 0.5 p.p.m. per volume at the tropopause to about 0.8 p.p.m. at around 27 km altitude. Above that altitude the H2 concentration decreases again. An air sample collected between 44 and 62 km by a rocket-borne cryogenic sampler had an H2 concentration of 0.4 p.p.m. The five CH4 profiles showed a decrease in CH4 concentration with altitude generally with a steeper gradient directly above the tropopause and a weaker gradient at higher altitudes reaching 0.9 p.p.m. at 30 km altitude. The CH4 concentration in the rocket sample was 0.25 p.p.m., in good agreement with the gradient obtained from the balloon samples.
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    Pure and applied geophysics 106-108 (1973), S. 1417-1430 
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    Notes: Abstract The consumption of both methane and carbon monoxide in the lower stratosphere is due predominantly to reaction with OH radicals. The possibility of deriving OH concentration from measurements of the decrease of CH4 and CO mixing ratios above the tropopause is explored. The observations and the basic chemistry are briefly summarized. Simple one-dimensional diffusion models are employed to derive expressions for the decrease of CH4 and CO mixing ratios with altitude above the tropopause, and the influence of important parameters is discussed. Vertical air velocities resulting from large-scale organized mean motion and from synoptic variations are shown to distort the concentration altitude profiles of methane and carbon monoxide, respectively. Suitable averaging of observational data is required to eliminate the effects due to vertical motion. Then a reliable value for the effective OH number density should be obtainable. At present an estimate of 4×106 molecules/cm3 is derived.
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    Pure and applied geophysics 106-108 (1973), S. 1464-1467 
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    Topics: Geosciences , Physics
    Notes: Summary The photolysis of ozone in the u.v. Hartley Band produces metastable oxygen atoms and molecules. At wavelengths shorter than 3100 Å the primary quantum yield is probably unity but greater uncertainty exists about its value at longer wavelengths. At 2500 Å, O2(1Δg) is produced with near unit efficiency and there is some evidence that singlet O2 is also a primary prduct at the short wavelenght end of the Huggins band. O2(1 Σ g + ) is not a primary photolytic product at 2500 Å but is produced as a secondary product from the rapid reaction of O(1D) with ground state O2. O(1D) reacts rapidly with O3 although the nature of the products of this reaction has not been unequivocally established and there is now strong evidence against the occurrence of energy chains in dry ozone. The reaction of O(3P) atoms with O3 has been found to have an activation energy of 4.4 kcal mole−1.
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    Pure and applied geophysics 106-108 (1973), S. 1498-1519 
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    Notes: Summary A steady-state mean meridional model of the stratosphere is used to investigate the effects of water vapour and nitrogen oxides on ozone and temperature distributions in the stratosphere. The Chapman classical photochemical scheme for ozone is extended to include the dominant reactions involving hydrogen compounds and nitrogen oxides. The ozone and temperature changes are studied under radiative-photochemical equilibrium conditions and in a model incorporating both transport and radiative-photochemical processes. It is found that both hydrogen and nitrogen reactions contribute to substantial decreases in ozone and temperature under photochemical equilibrium conditions, but the computed distribution do not resemble those observed. The effect of transport processes is to reduce the deviations in the ozone mixing ratio and temperature with the computed distributions having many features in common with the observations. It is found that the ozone and temperature respond more readily to the arbitrary increase of nitrogen oxides than to that of water vapour.
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    Pure and applied geophysics 106-108 (1973), S. 1544-1552 
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    Notes: Summary The intensity of the polar vortex at 10 mb is used to calculate theoretical values of mean total ozone north of 40° latitude. A satisfactory fit is attained between the development in time of the theoretical ozone and that of the mean of the observed total ozone. The results lead to the conclusion, that a one-cell mean meridional motion relative to the polar night vortex is important for the transport of heat and ozone.
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    Pure and applied geophysics 106-108 (1973), S. 1576-1580 
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    Notes: Abstract The vertical profiles of ozone and temperature from a series of balloon soundings at Delhi (28°N), Poona (18°N) and Trivandrum (8°N) were studied with synoptic meteorological data. While both ozone and temperature profiles show similar variations over all three stations, ozone maxima being always associated with thermally stable layers, the variations are most pronounced over Delhi, particularly in winter and in early spring when a series of western disturbances pass over north India. Both ozone and temperature profiles over Delhi show a layer structure characterized by a series of maxima and minima in both the vertical distribution of ozone and temperature and these are most pronounced in the lower stratosphere. These variations are associated with the influx of ozone-rich middle latitude stratospheric air over Delhi replacing subtropical air.
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    Pure and applied geophysics 106-108 (1973), S. 1586-1599 
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    Notes: Abstract The results of the observations of both total and layered ozone content of the atmosphere, the latter from C wavelength Umkehr observations, made in Lisbon (38° 46′N; 09° 09′W) during the period 1967 to 1971 by the Serviço Meteorológico Nacional, are analysed on a statistical basis in relation to the flow and temperature fields of the atmosphere, namely in relation to the position of the tropospheric jet axis and thê 100 mb air temperature. The preliminary results of the analysis show that the yearly mean variation of the total O3 follow the very well-known trend as observed for other geographical coordinates, with a winter to spring maximum. In addition, the same parameter is positively correlated to the 100 mb temperature field for the seasons of the year, and it was found, both on a large time-scale and for synoptic distributions, that the total amount of O3 is significantly higher a few hundreds of kilometres to the left of the jets looking downstream than to the right, so that mean cross-flow gradients of O3 are field features to be taken into account. The time-height distributions of ozone from the Umkehr technique has revealed, in the long-term mean used, a descent of the level of the maximum of around 20 mb depth from the summer-winter period to spring, but this descent may be much more pronounced on occasions, as revealed by the preliminary analysis of a few days' period of important ozone changes in relation to the potential temperature and jet axis position. this showed, in addition, the existence of varying gradients along the stream, whereby differences in circulation along the jet complex may be implied.
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    Pure and applied geophysics 106-108 (1973), S. 950-961 
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    Notes: Summary Ground-based photometric measurements of spectral sky radiation have been made using a simple filter instrument. Sky radiation intensities measured in the solar vertical at λ=3200 Å and 3600 Å are compared to infer total ozone. A model of multiple scattering Rayleigh atmosphere serves as a primary reduction parameter. Spectral measurements of all-sky radiance distribution are used to study the effects of haze and clouds on the inference of total ozone. The brightness distribution of clear and overcast sky in ultraviolet is also described.
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    Pure and applied geophysics 106-108 (1973), S. 1281-1289 
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    Notes: Abstract The intensity of stars at wavelengths in the Hartley continuum region of ozone has been monitored by the University of Wisconsin stellar photometers aboard the OAO-2 satellite during occultation of the star by the earth's atmosphere. These occultation data have been used to determine the ozone number density profile at the occultation tangent point. The nighttime ozone number density profile has a bulge in its vertical profile with a peak of 1 to 3×108 cm−3 at approximately 83 km and a minimum near 75 km. The ozone number density at high altitudes varies by as much as a factor of 4, but does not show any clear seasonal variation or nighttime variation. The retrieved ozone number density profiles define a data envelope that is compared with other nighttime observations of the ozone number density profile and also the results of theoretical models. Calculations are also presented that illustrate the difference in retrieving the bulge in the ozone number density profile from stellar and solar occultation data.
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    Pure and applied geophysics 106-108 (1973), S. 938-946 
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    Notes: Abstract With the evaluation of sunlight or skylight spectra within the Huggins bands the amount of ozone along the optical path, as well as its average temperature, can be derived from the contrast of the measured bands independently. By sufficient resolving power of the spectrograph and an appropriate choice of measuring points within the spectrum the influence of all other extinctions can be eliminated with a very small interpolation error. Therefore this method is adequate as a reference measurement to the other usual methods of ozone measuring. A spectrograph with the properties to be postulated was built. Preliminary experiences and results are reported and the accuracy which may be expected for this method is discussed.
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    Development genes and evolution 172 (1973), S. 287-302 
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    Topics: Biology
    Description / Table of Contents: Résumé L'analyse de certains points de la morphogénèse du canal de Müller et du rôle joué par le canal de Wolff dans la formation de l'oviducte a été abordée à l'aide de diverses méthodes expérimentales (blocage de l'ébauche müllérienne par un obstacle mécanique ou par une irradiation localisée par les rayons X). Les résultats obtenus soulignent la formation et l'évolution indépendante des 2 tissus, l'epithélium interne et le mésenchyme périphérique, qui composent la jeune ébauche müllérienne. L'épithélium interne se met en place par le jeu de la croissance crânio-caudale d'une ébauche primitive formée au niveau de l'ostium et induite par le canal de Wolff. Le mésenchyme périphérique se forme «in situ», aux dépens de la crÊte mullérienne qui est elle-mÊme induite par le canal de Wolff. Chez les Oiseaux, le développement de l'oviducte reste donc dépendant de l'uretère primaire, du fait de la double action inductrice exercée par le canal de Wolff sur les deux tissus constituant primitivement le canal de Müller.
    Notes: Summary Certain points in the Mullerian duct morphogenesis, and the role played by the Wolffian duct in oviduct formation, were studied with some experimental methods (by stopping the mullerian anlage with a mechanical obstacle, or by a localized irradiation with X-rays). The results emphasize the independent formation and evolution of the two tissues, the inner epithelium and the mesenchyme which compose the young mullerian anlage. The inner epithelium is formed by the cranio-caudad outgrowth of a primitive anlage, formed at the level of the ostium, and induced by the Wolffian duct. The peripheric mesenchyme is formed “in situ”, from the mullerian strip, which itself is induced by the Wolffian duct. In Birds, oviduct development depends upon the primary ureter, by means of the double inductive action exerted by the Wolffian duct upon both tissues constituting the Mullerian duct anlage.
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    Description / Table of Contents: Zusammenfassung Eine intensive Anreicherung des Glykogens bei der Oogenese des Schlammpeitzgers (Misgurnus fossilis L.) fällt mit der Umwandlung der Glykogensynthetase (EC 2.4.1.11) in die I-form (aktive) Form des Fermentes nicht zusammen. In den isolierten Oocyten und Embryonen des Schlammpeitzgers wandelt das Insulin die Glykogensynthetase in die Form um, die der Inhibition von ATP gegenüber desensibilisiert worden ist. Das Insulin erhöhtV max nur bei Überschuß des Aktivators Glu-6-P, bleibt aber ohne Wirkung auf denK m-Weit für UDP-glucose. Das Insulin wandelt jedoch die Phosphorylase (EC 2.4.1.1) in die latente Form um.
    Notes: Summary Glycogen synthetase (EC 2.4.1.11) from oocytes and embryos of the loach (Misgurnus fossilis L.) has been found only in the D-form. The intensive glycogen accumulation during oogenesis did not correspond with the glycogen synthetase interconversion in the I-form. In isolated oocytes and embryos of the loach insulin transforms glycogen synthetase into the form which is desensitized for ATP inhibition. Insulin treatment enhancesV max without affecting theK m (UDP-glucose) only with an excess of activator—glucose-6-P. Simultaneously insulin treatment converts the phosphorylase (EC 2.4.1.1.) into the latent form.
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    Development genes and evolution 173 (1973), S. 9-21 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Ein unbefruchtetes Ei und ein intakter Schlammpeitzgerembryo (Misgurnus fossilis L.) weisen dieselbe Aktivität der Phosphorylase (EC 2.4.1.1) und ein konstantes Verhältnis zwischen der aktiven und der latenten Phosphorylase auf. Nach dem Stadium der 32 Blastomeren wurde im vom Eidotter isolierten Embryo (Blastoderm) eine Zunahme der Aktivität der Phosphorylase und die Zunahme des Glykogengehaltes festgestellt. Diese hört nach Beginn der Gastrulation auf. Die Verfasser begründen ihre These von der Übertragung der glykogengebundenen Phosphorylase aus dem Eidotter in den Embryo in den Phasen am Ende der Furchung und in der Blastula. In der Oozyte, im unbefruchteten Ei und im Embryo ist nur ein unbedeutender Teil der Phosphorylase mit dem granulären Glykogen verbunden. Die hauptsächliche Aktivität der Phosphorylase (etwa 80%) ist mit dem bei 144000 g nicht absetzbaren niedermolekularen Glykogen verbunden, das 30% des gesamten Glykogengehaltes nicht übersteigt. Die Glykogensynthetase (EC 2.4.1.11) ist umgekehrt mit dem granulären Glykogen verbunden. Das Reifen der Oozyte, die Ovulation und der Beginn der Furchung sind nicht in die Umverteilung der Fermente zwischen den Fraktionen des Glykogens verschiedenen Molekulargewichtes verwickelt.
    Notes: Summary An acceleration of the rate of glycogenolysis in the early embryogenesis of the loach (Misgurnus fossilis L.) is accompanied by an increase of the content of hexose monophosphates, the rate of lactate formation and the rate of respiration. The unfertilized egg and the intact embryo of the loach have an identical activity of phosphorylase (EC 2.4.1.1.) and a constant ratio of the active/latent phosphorylase. Following the stage of 32 blastomeres, an increase of phosphorylase activity and the glycogen content occurs in the yolk-free embryo (blastoderm); this increase stops after the onset of gastrulation. In view of the facts that a) the blastoderm contains practically no latent phosphorylase, b) an elevation of phosphorylase activity is synchronized with an increase of the glycogen content, and c) this process is not related to an increase of the total phosphorylase activity and glycogen content in the intact egg, the authors suggest that glycogen-bound phosphorylase transfers from the yolk to the embryo at the stages of cleavage and blastula. In the loach oocyte, unfertilized egg and embryo the main activity of phosphorylase (more than 3/4) is associated with low molecular weight glycogen; this form of glycogen cannot be sedimented at 144000 g, and constitutes not more than 30 % of the total glycogen. Glycogen synthetase (EC 2.4.1.11) is, on the contrary, bound completely with granular glycogen. The oocyte maturation, ovulation and the onset of glycogenolysis after fertilization do not involve a redistribution of enzymes between glycogen fractions of different molecular weights. An increase of the glucose level in oocytes accelerates the conversion of active phosphorylase into its latent form. Physiological concentrations of glucose (up to 2 × 10−2 M) do not inhibit phosphorylase activity.
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    Development genes and evolution 173 (1973), S. 77-82 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Entwicklung des Hämolymphproteinspektrums im letzten Larvenstadium von Ephestia ist durch zwei besondere Charakteristika gekennzeichnet: 1. während der Freßperiode tritt eine neue Bande (3) erstmals auf, 2. in der Vorpuppenphase wird eine andere Fraktion (2) aus dem Blut eliminiert und im Fettkörper akkumuliert. Unter oraler Farnesylmethyläther-Dauerapplikation wachsen Tiere des letzten Raupenstadiums zu überdurchschnittlicher Größe heran, führen aber in der Regel keine Häutung mehr durch. Dabei wird das Auftreten der Bande 3 in der Hämolymphe nicht verhindert. Es unterbleibt jedoch die Verarmung des Blutes an Fraktion 2 und die Akkumulation dieser Zone im Fettkörper.
    Notes: Summary The pattern of development of haemolymph proteins in the last larval stage of Ephestia shows two characteristic features: 1. A new band (fraction 3) makes its appearance during the feeding period of the larva, 2. In the prepupal stage another protein (fraction 2) disappeares from the haemolymph. but it is accumulated in the fat body. On continuous oral administration of farnesyl methyl ether most of the last stage larvae grow to abnormal sizes without any additional moult. The appearance of fraction 3 in the haemolymph is not inhibited, but reduction of fraction 2 in the blood and its corresponding accumulation in the fat body are not observed.
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    Development genes and evolution 173 (1973), S. 83-106 
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    Development genes and evolution 173 (1973), S. 107-121 
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    Description / Table of Contents: Zusammenfassung 1. Die Metamorphose der Planulae vonHydractinia echinata (Hydrozoa) wird durch bestimmte marine, gramnegative Bakterien ausgelöst, die gegen Ende des exponentiellen Wachstums ein stimulierendes Prinzip freisetzen. 2. Der Reiz wird nur von stationären Zellen nach Anzucht bei niederer Populationsdichte (bis zu 107 Zellen/ml) in einem geeigneten Medium (z.B. Fleischextrakt) abgegeben. Übertragung der Mikroben in Nährstoff-freies Seewasser erhöht ihre Induktionskapazität. 3. Die Konzentration des Induktors übertrifft normalerweise den Schwellenwert nur in der engsten Umgebung lebender Bakterien. Nur wenn die Mikroben durch einen plötzlichen Abfall des osmotischen Drucks geschockt werden, hinterlassen sie im filtrierten Medium nachweisbare Spuren. 4. Entsprechend kann das Agens durch ein osmotisches Schockverfahren, das die Mikroben am Leben läßt, angereichert und isoliert werden. Der Induktor gehört zu einer Kategorie mikrobieller Substanzen, die unter dem Begriff “leakage” -Produkte zusammengefaßt werden. 5. Das aktive Prinzip kann aus der leakage-Lösung mit Aceton gefällt und mit Chloroform extrahiert werden. Es scheint ein instabiles, nicht-dialysierbares, polares Lipid zu sein. 6. Um eine vollzählige und vollständige Metamorphose zu erzielen, muß der isolierte Induktor in Art eines Pulses appliziert werden. Nimmt man den Beginn der Metamorphose als Maß der Reaktionsgeschwindigkeit, zeigen die Dosis-Wirkungskurven einen Michaelisartigen Sättigungsverlauf. Bei kurzen Pulsen ergeben die Prozentsätze induzierter Metamorphosen ebenfalls eine Sättigungskurve. Dies deutet die Beteiligung eines Enzyms oder Carrier-systems bei der larvalen Reaktion an. 7. Der induzierende Effekt wird durch gleichzeitige Applikation von Ouabain gehemmt. Umgekehrt kann eine hohe Dosis an leakage-Material den Ouabainhlock überrollen. Die Primärwirkung des Induktors kann somit als Stimulation des aktiven Kationentransports, speziell als Stimulation der Na+/K+-ATPase interpretiert werden.
    Notes: Summary 1. The metamorphosis of the planulae ofHydractinia echinata (Hydrozoa) is induced by certain marine, gramnegative bacteria which at the end of the exponential growth release a stimulating principle. 2. The stimulus is liberated by stationary cells previously cultivated at low population densities (up to 107 cells/ml) in a proper medium (e.g. extract of meat). Transfer into seawater lacking nutritive sources enhances the inductive capacity. 3. The concentration of the inducing agent normally surpasses the threshold level only in the close microenvironment of living cells. But when shocked by a drop in the osmotic pressure the bacteria discharge increased amounts which become traceable in the filtered cell-free medium. 4. Thus the inducer can be accumulated and isolated by a process of osmotic shock which does not affect the viability of the microbes. The principle belongs to a category of microbial substances which are subsumed under the comprehensive term „leakage“-products. 5. The active principle can be precipitated from the leakage solution with acetone and extracted with chloroform. The inducer seems to be an unstable, nondialyzable, polar lipid. 6. In order to evoke complete metamorphosis the isolated agent must be applied in a pulse-like fashion. Using the onset of metamorphosis as criterion for the velocity of reaction the dose-response curves display Michaelis-like saturation kinetics. At short pulses the percentages of induced metamorphoses yield a saturation curve as well. This indicates that an enzyme or carrier-system is involved in the larval response. 7. The inducing effect of the bacterial principle is antagonized by ouabain. Conversely, high doses of the isolated leakage material abolish the ouabain inhibition. The primary effect of the inducer, therefore, can be interpreted as stimulation of the active cation transport, especially of the Na+/K+-ATPase.
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    Development genes and evolution 173 (1973), S. 136-163 
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    Topics: Biology
    Notes: Summary UsingAmbystoma mexicanum blastulae (Harrison 7 2/3 to 10−), a study was made of the morphogenetic behaviour of the endoderm, both in isolation and upon recombination with marginal zone material. It was shown that the endoderm autonomously forms “flask cells” and thus a blastoporal groove, when isolated at or after the mid-blastula stage (8+). The frequency of blastopore formation decreases as the endoderm is isolated at successively younger stages. At the youngest operable stage (7 2/3) a blastoporal groove is formed in 30% of the isolates. Recombination with marginal zone material promoted blastopore formation in endoderm isolated at stage 7 2/3; the frequency of blastopore formation was maximal (90%) in recombinates with dorsal marginal zone from stages 7 2/3 and 8 1/2, while in recombinates with older dorsal (stages 9 and 10−) or with ventral marginal zone (stages 7 2/3 to 10−) it was lower (60%). Blastopore formation could only be evoked on the dorsal side of the endoderm. Ventral halves of stage 10− endoderm are unable to form flask cells, whereas the complete endoderm forms flask cells ventrally as well as dorsally, demonstrating the leading role of the dorsal endoderm in flask cell formation. Only the left half of the dorsal or ventral marginal zone was used in the recombinates, the corresponding right half being culturedin vitro. Differentiation of mesoderm in these control explants was used as a criterion for the presence of induced mesoderm in the marginal zone material at the time of recombination. Differentiation was poor, however, which affects the reliability of this criterion. No relation could be found between the presence of induced mesoderm in the isolated marginal zone material and the incidence of gastrulation phenomena in the endoderm/marginal zone recombinates. Thus the results of these experiments provide no evidence for a gastrulation-inducing role of the induced mesoderm, as proposed by Nieuwkoop (1969a). Alternatively, the results suggest that the endoderm may acquire its capacity for blastopore formation as a direct consequence of the earlier dorso-ventral polarization of the embryo, without the intervention of the induced mesoderm. Synchronization of endodermal and mesodermal gastrulation movements must be established during mesoderm induction.
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    Development genes and evolution 171 (1973), S. 259-268 
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    Topics: Biology
    Notes: Summary A method is described for the maceration (dissociation) of hydra tissue into single cells. The cells have characteristic morphology such that all basic types — epithelial, gland, mucous, interstitial, nematoblast, and nerve — can be distinguished. Criteria are given for identifying each cell type by phase contrast microscopy. It is shown that maceration quantitatively recovers cells from hydra tissue.
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    Development genes and evolution 171 (1973), S. 301-311 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. Nach der Applikation von Tritium-markierten Aminosäuregemischen wurden anhand von Autoradiogrammen die verschiedenen Entwicklungsstadien bis zum späten Blastoderm untersucht. Kurze Inkubationszeiten dienten zur Analyse der Proteinsyntheseraten. Radioaktive Markierungen nach langzeitigen Inkubationen gaben AufschlÜsse Über Lokalisation und Inkorporationsmuster von Eiproteinen. 2. Der periphere Eibereich ist während der intravitellinen Furchung und Blastodermentwicklung der Einlagerungsort neusynthetisierter Proteine. Morphologische Entwicklungsprozesse, wie die Bildung von Zellmembranen oder die des sekundären Periplasma, sind durch den lokalen Einbau stärkerer Aktivität charakterisiert. Entwicklungsphysiologische Aktivitäten werden durch intensive radioaktive Schwärzung Über Zellkernen des Blastoderm und Vitellophagen sichtbar. 3. Schon kurz nach der Eiablage ist eine bestimmte Proteinsyntheserate nachzuweisen. Sie steigt zunächst nur wenig, mit der Blastodermbildung aber erheblich an. Dann erhöht sich die Inkorporationsrate geringfÜgig, um in einem späten Blastodermstadium ein Maximum zu erreichen. Gegen Ende der Blastodermentwicklung wird die Syntheserate schwächer. 4. Typische Entwicklungsabläufe sind, schon bevor sie morphologisch erkennbar werden, durch eine stärkere Syntheseaktivität physiologisch gekennzeichnet. Der Membranbildung sowie der Formierung des sekundären Periplasma geht jeweils ein signifikanter Anstieg der Proteinsyntheserate voraus.
    Notes: Summary 1. 3H-amino acid incorporation into newly synthetized egg proteins was investigated by means of autoradiography in order to analyze the synthesis rate of different developmental stages. Furthermore the incorporation pattern of the egg system was studied to find out whether physiological and morphological processes during early embryogenesis are connected with a certain protein synthesis. The tritium-labelled amino acids were injected into the yolk system of the egg, since the yolk proteins serve as amino acid sources for embryogenesis. 2. There is a permanent transfer of radioactivity from the yolk system into the cortical egg regions during intravitelline cleavage and blastoderm development. Therefore the radioactivity is continuously accumulating in these areas. Typical morphological processes like the formation of cell membranes and the secondary periplasm are characterized by local region specific incorporation of radioactivity. The physiological activities of blastoderm nuclei and vitellophages seem to be linked directly with high incorporation of the3H-amino acids. 3. A certain protein synthesis rate already takes place shortly after egg deposition. During intravitelline cleavage its value rises only slowly. But with migration of the cleavage nuclei into the periplasm the synthesis rate begins to increase rapidly to more than 100% of its original amount. In the first blastoderm stages the permanent increase of the synthesis is less than before and reaches its maximum in the late blastoderm. Near the end of blastoderm development the protein synthesis rate is slightly reduced. 4. Characteristic developmental processes can be determined by significant increases of the protein synthesis before they become morphologically detectable. Immediately before the formation of cell membranes and the secondary periplasm a higher synthesis rate was identified.
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    Topics: Biology
    Notes: Summary 1. Eggs of the blowflyProtophormia spec. were separated into anterior and posterior fragments of varying sizes. The operations were carried out between oviposition and the blastoderm stage. The partial larvae produced by the fragments were scored for the cuticular pattern they had formed. 2. The cuticle of the 1st instar larva carries 11 denticle belts which correspond to the anterior borders of the thoracic and abdominal body segments. These are considered the elements of a linear longitudinal pattern which starts with the head region. 3. Egg fragments of the sizes studied did not produce the complete cuticular pattern. 4. If denticle belts were present on the partial larvae formed in egg fragments, these always included the corresponding terminal pattern element (no. 1 in anterior, no. 11 in posterior fragments). Bigger partial patterns from anterior fragments may have any belt up to no. 10 as their most posterior belt, posterior partial patterns may start anteriorly with any belt up to no. 1, i.e. behind the head region. 5. After fragmentation during early stages of development, all eggs fail to form some pattern elements. Fragmentation thus causes a gap in the pattern. Extent and position within the pattern of this gap depend on level and stage of fragmentation. 6. With increasing egg age (developmental stage) at fragmentation, the gap in the cuticular pattern becomes progressively smaller. Eggs fragmented during or after formation of the blastodermal cell walls as a rule form all pattern elements. 7. The progressive reduction of the gap in the cuticular pattern is due to formation of bigger sets of pattern elements inboth partner fragments. I.e. on the average an anterior or posterior fragment of given size will produce more pattern elements if separated from the rest of the egg at a later stage than if separated early. 8. In order to produce a given set of pattern elements, a fragment needs to be bigger on the average when separated early than when separated later on. This applies to both anteriorand posterior fragments of the fragmentation levels studied. 9. According to these results, the egg ofProtophormia cannot be considered a mosaic of determinants for the different pattern elements at oviposition. The developmental fate of at least the more equatorial egg regions appears to become specified epigenetically during the period between oviposition and blastoderm formation. 10. Once the egg has become subdivided into blastoderm cells, it reacts as a developmental mosaic with respect to the pattern studied. 11. Preliminary results inDrosophila are compatible with these conclusions. 12. The results are compared to those obtained from other insect groups, and formal models for their interpretation are discussed. Pattern specification by interaction of terminal egg regions can be considered the common denominator for a number of egg types. 13. The results demonstrate that formally comparable processes of pattern formation occur in different insect egg types at different stages of development.
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    Development genes and evolution 172 (1973), S. 58-65 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. Bei Applikation Tritium-markierter Aminosäuren vor der Keimanlagenbildung wird die Aktivität superfiziell eingebaut. Regionale Unterschiede in der Proteininkorporation sind nicht erkennbar. 2. Nach der Formierung der Keimanlage sind dagegen die extraembryonalen Eibereiche vom Einbau des Tracers weitgehend ausgenommen. Lediglich bei der Bildung des extraembryonalen Hüllgewebes gelangt in die Amnionfalte verstärkt Radioaktivität. Außerdem ist das Ektoderm intensiver radioaktiv markiert als die Coelomepithelien, was Hinweise auf dessen Entwicklungsvorsprung in der Organdifferenzierung gibt. 3. Das spezifische Proteineinbaumuster im Bereich der Blastemzellen zeigt neben der allgemeinen Aufnahme von Radioaktivität in Cytoplasma und Zellkerne eine Zone erhöhter Silberkorndichte unmittelbar an der Kernmembran. Hier muß ein Ort starker Eiweißsynthese sein.
    Notes: Summary 1. Tritium-labelled amino acids were injected into the yolk system of theDermestes egg in order to analyze the protein metabolism during early differentiation of the embryonic germ layers and to prove whether the differentiation pattern in early organogenesis corresponds with the uptake of radioactivity. 2. Before germ anlage formation the radioactivity is incorporated homogeneously in all superficial cell regions (Abb. 1), but with the separation of the embryonic blastemas just prior to the invagination of the middle plate the presumptive serosa is excluded from the uptake of3H-labelled amino acids. Only in amnion development do regions of the cellular protective membranes which cover the germ band incorporate radioactivity especially in the nuclei (Abb. 2c). 3. During the formation of the inner germ layers and the following development of coelomic sacs from middle plate material and of ventral nerve cord from the ectoderm, the incorporation of radioactivity into the embryonic blastemas continues. But now it is much more intense in ectoderm cells (Abb. 2e). These results indicate that the differentiation processes are probably further developed in the ectoderm than in other embryonic blastemas in agreement with studies on the developmental potencies of germ layers which are discussed. 4. Besides the uptake of radioactivity into the cytoplasm of the embryonic cells a specific incorporation of the3H-amino acids into the nuclei has been observed. When the tracer was injected at an early stage of germ band formation offering the labelled amino acids for a long period in development the radioactivity accumulates in a small zone surrounding the membranes of the nuclei (Abb. 2d, g). It is assumed that in this region specific incorporation of radioactivity could be a visible indication of cell differentiation in early organogenesis.
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    Development genes and evolution 172 (1973), S. 131-148 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. Mittels histologischer Methodik und Trockenpräparation wurden die Hinterbeinknospen der AnurenartenAlytes obstetricans, Bombina variegata, Rana temporaria, Rana esculenta, Bufo bufo undBufo calamita auf die Existenz einer Epidermisleiste hin untersucht. 2. Für alle sechs Anurenarten konnte der Nachweis einer Epidermisleiste erbracht werden. Die Epidermisleiste vonAlytes obstetricans ist durchaus vergleichbar mit derjenigen der Amnioten. 3. Die Epidermisleiste entsteht beiAlytes obstetricans, Rana temporaria undRana esculenta durch Vermehrung der Zellschichten und Ausbildung einer prismatischen Basalschicht. BeiBufo bufo, Bufo calamita undBombina variegata nur durch Bildung der prismatischen Basalschicht. 4. Die Epidermisleiste ist bei allen sechs Anurenarten vom Zeitpunkt, da die Extremitätenknospe ungefähr so lang als breit ist bis spätestens zur beginnenden Ausbildung der Phalangenhöckerchen nachweisbar. 5. Mit Ausnahme vonBufo calamita verläuft die Epidermisleiste asymmetrisch über die Spitze der Extremitätenknospe, indem sie sich präaxial weiter gegen proximal erstreckt als postaxial. 6. Die Marginalvene ist erst nach Beginn der Leistenausbildung nachweisbar. Sie verläuft eine bis mehrere Zellschichten unterhalb der Basalmembran der Leiste entlang. 7. BeiAlytes obstetricans undRana temporaria sind vorübergehend in der Epidermisleiste vermehrt pyknotische Zellen nachweisbar.
    Notes: Summary 1. The hindlimb buds of AnuraAlytes obstetricans, Bombina variegata, Rana temporaria, Ranma esculenta, Bufo bufo andBufo calamita were investigated for the presence of an apical ectodermal ridge using histological techniques and dry preparations. 2. In all six Anura species an apical ectodermal ridge was found to be present. The ridge ofAlytes obstetricans, in particular, is comparable with that of Amniota. 3. InAlytes obstetricans, Rana temporaria andRana esculenta an increase in cell layers and development of basal columnar cells leads to the formation of the apical ectodermal ridge, while as inBufo bufo, Bufo calamita andBombina variegata the development of the basal columnar cells alone forms the ridge. 4. The apical ectodermal ridge exists from the stage when the limb buds are approximately the same length as breadth until the beginning of the digit formation. 5. With the exception ofBufo calamita the apical ectodermal ridge extends asymetrically over the apex of the limb bud being longer on the preaxial side. 6. The marginal vein is only visible after the ridge development has begun. It underlies the ridge in the mesenchyme one or more cell layers beneath the basal membrane. 7. InRana temporaria andAlytes obstetricans an increased percentage of pycnotic cells is found within the ridge during a particular period.
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    Development genes and evolution 172 (1973), S. 196-222 
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    Description / Table of Contents: Zusammenfassung Erster Teil 1. Eine Gefriermethode wurde entwickelt, die es ermöglicht, Imaginalscheiben (IS) undin vivo-kultivierte Primordien, wie auch embryonales Neoplasma vonDrosophila melanogaster in flüssigem Stickstoff aufzubewahren. 2. VerschiedeneSalzlösungen prüften wir auf ihre Eignung für unser Gefriermedium. Dabei wurde festgestellt, daß sieh Salzlösungen kombiniert mit organischen Zusätzen besser eignen als reine. Es läßt sich nicht ausschließen, daß die beigemischten Zucker nebst Glyzerin als zusätzliche Gefrierschutzmittel wirken. 3. Glyzerin wurde dem Dimethylsulfoxid (DMSO) alsGefrierschutzmittel vorgezogen wegen seiner Unschädlichkeit für Insektengewebe. 4. Fügt man dem Gefriermedium keineProteine zu, überleben die IS die Gefrierbehandlung, werden jedoch stark klebrig. Dies führt während der Weiterbehandlung des Materials zu Zellverlusten. In unserem 10%igen (v/v) Glyzerin-Gefriermedium reduziert eine zu hohe Proteinkonzentration die Gefrierschutzwirkung. Wegen seinem relativ hohen Proteingehalt fällt daher fötales Kalbserum als Proteinlieferant aus. An seine Stelle tritt das gereinigte und dosierbare Protein Bovine Serum Albumin. Für Imaginalscheiben-Gewebe wird eine 10%ige (v/v) Konzentration von DMSO im Gefriermedium als zu konzentriert befunden. Dies verlangt unnötig viel Protein zur Bindung von freiem, toxisch wirkendem DMSO. 5. Als optimaleGefriergeschwindigkeit für unser Gewebe fanden wir 1° C/min. DieAuftaugeschwindigkeit entspricht 100° C/min. 6. Einen Einfluß der Gefrierbehandlung auf Determinations- und Differenzierungs-Lei-stungen ließ sich nicht nachweisen. Es wurde auch keine Beeinflussung derTransdetermination festgestellt. Zweiter Teil 7. Die für Imaginalscheiben entwickelte Gefriermethode wurde auf ihre Eignung fürlarvale Ovarien vonDrosophila melanogaster geprüft. 8. Das dabei angewandte direkte Eintauchen der larvalen Ovarien ins Gefriermedium, scheint die azelluläre Hüllmembran zu schädigen. Beim darauffolgenden Gefrier- und Auftauprozeß entstehen lokale Zellverluste, die zum Absterben des larvalen Ovars führen können. 9. Eine schrittweise Überführung der larvalen Ovarien in eine höhere Konzentration an Gefrierschutzmittel im Gefriermedium, verhindert diese als osmotischen Schock bezeichnete Auswirkung. 10. Je nach verwendetem Genotyp überleben zwischen 66 und 74% der larvalen Ovarien die Gefrierbehandlung. 11. Die nach dem Auftauen der larvalen Ovarien direkt ausgeführte Reimplantation in larvale Wirte entscheidet über den effektiven Erfolg der Gefriermethode. Wir stellen dabei prozentual geringe Unterschiede zwischen den Ergebnissen gefrierbehandelter und unbehandelter Implantate fest. 12. Transplantierte larvale Ovarien werden mit einer ihrem Genotyp entsprechenden Wahrscheinlichkeit an den Wirtsovidukt angehängt. Erfolgreich angeheftete Implantate, gefrierbehandelt oder unbehandelt, liefern im Verhältnis zum verbleibenden Wirtsovar bedeutend weniger Eier. 13. Die Eignung der neu entwickelten Gefriermethode zur Gefrierkonservierung vonDrosophila-Mutantenstämmen wird diskutiert.
    Notes: Summary First part 1. A deep freezing technique has been developed inDrosophila melanogaster which makes it possible to freeze (1) imaginal discs, (2) blastemas of imaginal discs which have been culturedin vivo and (3) embryonic neoplasms. 2. The suitability of differentsalt solutions for our freezing medium has been tested. It is clear that salt solutions containing organic additives are more suitable than are pure ones. It remains to be determined if, in addition to glycerol, the added sugars also act as freezing protectives. 3. Glycerol as a freezing protective (i.e., cryoprotective) is much better than Dimethylsulfoxide (DMSO) since it was shown not to be toxic to insect tissue. 4. In either the presence or the absence ofprotein in the freezing medium the imaginal discs survive the freezing process. However, without protein the tissue becomes sticky which makes successful transplantation virtually impossible. When the concentration of protein is high (6 mg/ml) in a 10% (v/v) glycerol-freezing medium, the protecting effect is considerably reduced. In contrast, a 10 % (v/v) DMSO-freezing medium requires such a high concentration of protein in order to reduce the toxic effects of the DMSO itself. As protein components, both Fetal Calf Serum (FCS) and Bovine Serum Albumin (BSA) are possible. However, since the concentration of protein in FCS is high and, in addition, the correct dose of protein cannot be measured out, the purified protein BSA is more suitable. 5. The optimalfreezing-velocity for our tissue is 1° C/minute. Thethawing-velocity is 100° C/ minute. 6. The freezing process has no detectable effect on determination and differentiation, nor ontransdetermination. Second part 7. The suitability of the technique for freezing imaginal discs has also been tested withlarval ovaries ofDrosophila melanogaster. 8. The normal practice of dipping imaginal discs directly into the freezing medium cannot be applied to larval ovaries. Specifically, under these conditions the membrane of the larval ovary is damaged. Due to this osmotic shock the processes of freezing and thawing lead to the loss of cells and eventual death of the larval ovary. 9. Osmotic shock is not observed if the larval ovaries are stepwise transferred to progressively higher concentrations of cryoprotective in the freezing medium. 10. As a function of the genotype, between 66 and 74% of the larval ovaries survive the freezing process. 11. Reimplantation of the larval ovaries into larval hosts is decisive for the effective success of the freezing method. However, there is virtually no difference in the subsequent development of either freeze-treated or untreated implants. 12. Transplanted larval ovaries connect to the host oviducts with a certain probability which is related to their genotype. In any case, donor ovaries, freeze-treated or untreated, produce on the average much less offspring than do host ovaries. 13. The suitability of the newly developed freezing technique for the conservation ofDrosophila mutant stocks is discussed.
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    Development genes and evolution 173 (1973), S. 228-234 
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    Topics: Biology
    Notes: Summary The organ culture technique was used for the study of early cytodifferentiation in explanted rat and mouse embryonic shields. After 15 daysin vitro the main tissues were differentiated in explants. The full differentiation depended on the presence of homologous serum in the culture medium. 95% oxygen in the atmosphere was either deleterious or without measurable effect if introduced from the beginning or toward the end of the cultivation period, respectively. Some chemically defined media supported the development for only a limited time span during the initial period of cultivation.
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    Development genes and evolution 173 (1973), S. 235-248 
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    Topics: Biology
    Notes: Summary The regeneration (organogenesis was studied by Emig, 1972 a, b) of Phoronida can be divided into three phases: the first one, cicatrisation, is characterized by a provisional mesodermal scar-tissue, later the old epidermis cover this scar-tissue. The regenerating blastema, second phase, takes place by cellular dedifferentiation processes; each germ layer (ectoderm, mesoderm, endoderm) regenerates itself from its own elements. One exception only seems to be oesophagel regeneration by “metaplasia” of the prestomacal cells during the asexual reproduction. The differentiation of the amputated structures (third phase) appears submitted to the inductive influence of the mesoderm and to the trophic action of the nervous system (especially the epithelial plexus). The polarity in regeneration sets a problem in Phoronida.
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    Development genes and evolution 173 (1973), S. 283-293 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Amphibien-(Triturus alpestris)-Ektoderm wurde isoliert und nach 2–16 Tagen elektronenmikroskopisch untersucht. Es konnte gezeigt werden, daß sich Ektoderm, früher oft als „undifferenziertes Ektoderm“ bezeichnet, zu Epithelzellen differenziert, die zum Teil Cilien tragen. Diese Epithelzellen unterscheiden sich in ihrer Ultrastruktur nicht von Epidermiszellen, die sich in situ (also im Ganzkeim) entwickelt haben, lassen jedoch die typische flächige Anordnung der Epidermis vermissen. Die Cilien besitzen die gleiche Feinstruktur, wie sie bei Cilien der Protozoa oder Spermien von Insekten oder Wirbeltieren zu finden sind. Nach 4 Tagen Aufzucht bildet sich im Bereich der Peripherie der Epidermiszellen eine Zone aus, die frei ist von Dotterschollen, Mitochondrien und Embryonalpigment. Diese Zone ist reich an vacuolenähnlichen Strukturen und Basalkörpern der Cilien. Ektoderm, das mit vegetalisierendem (mesodermal/entodermal) induzierendem Faktor behandelt wurde, differenziert sich zu mesodermalen und entodermalen Geweben. Sowohl Cilien als auch die charakteristische periphere Zone werden in induziertem Gewebe nicht gebildet. In Ektoderm, das über 6 Std mit Aktinomycin D (1 μg/ml) behandelt wurde, ist die Bildung der peripheren Zone und der Cilien verzögert.
    Notes: Summary Amphibian (Triturus alpestris) ectoderm was isolated and after 2–16 days in culture examined by electron microscopy. It has been shown that the ectoderm, formerly called “undifferentiated ectoderm”, forms in part ciliated epithelial cells, which cannot be distiguished from the cells of the epidermis, which has developed in situ (except for the alignment of the cells which depends on the mesenchyme underlying the epidermis). The ultrastructure of the cilia is similar to that of cilia of protozoa or sperms of insects or vertebrates. A zone at the periphery of the epidermal cells, free of yolk platelets, mitochondria and pigment granules (embryonic pigment) is observed after 4 days. This area is rich in vacuolous structures and basal bodies of the cilia. Ectoderm, which was treated with the vegetalizing factor differentiates into mesodermal and endodermal tissues. Cilia, as well as the characteristic peripheral zone, are not formed in the induced ectoderm. In ectoderm treated with actinomycin D (1 μg/ml for 6 h) the differentiation of the peripheral zone and the cilia is delayed.
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    Development genes and evolution 173 (1973), S. 294-318 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. Der Normalbestand der Nematocyten in den Tentakeln und im Rumpfektoderm vonHydra attenuata Pall. zeigt eine große Variabilität. Die Variabilität der Nematocyten je Tentakel manifestiert sich nicht nur, wenn zwischen Individuen des gleichen Klons verglichen wird, sondern sie ist ebenso groß, wenn die Tentakel ein und desselben Polypen einander gegenübergestellt werden. 2. Die relativen Häufigkeiten der einzelnen Nematocyten-Typen in den Tentakeln und im Rumpfektoderm zeigen eine größere Konstanz als die absoluten Werte. Aus dem Vergleich der relativen Häufigkeiten der differenzierten Nematocyten des Rumpfes mit denjenigen der Tentakel ergibt sich, daß die einzelnen Typen in diesen beiden Körperregionen des Polypen mit unterschiedlicher Häufigkeit auftreten. 3. Durch chemisch-mechanische Behandlung können 90% der in den Tentakeln vorhandenen Stenotelen (Penetranten) zur Explosion gebracht werden, während sich die Isorhizen (Glutinanten) und Desmonemen (Volventen) unter gleichen Bedingungen nicht entladen. 4. Die Reaktion des Polypen auf selektiven Stenotelen-Verbrauch gliedert sich in 3 Phasen: a) In einer ersten Nachschubphase wandern die bereits im Rumpfektoderm vorhandenen, differenzierten Stenotelen in die Tentakel. b) In einer zweiten Phase werden die synchron erfolgenden Teilungen der bereits determinierten Blasten-Gruppen der Stenotelen frühzeitig unterbrochen, um eine vorzeitige Differenzierung zu erreichen. c) In einer dritten Phase wird die Produktion der Stenotelen im Sinne einer langfristigen, regulatorischen Maßnahme auf dem Niveau der Neudifferenzierung gesteigert. Diese Produktionssteigerung erfolgt einerseits durch vermehrte Determinationen von Stammzellen (I-Zellen) zu Stenotelen-Nematoblasten und andererseits durch Vermehrung der synchronen Teilungen, d.h. der Zahl der Nematoblasten je Gruppe. 5. Der massive Verbrauch von Stenotelen wirkt sich auch auf das Verhalten der Desmonemen aus, indem einerseits die zur Zeit des Stenotelen-Verbrauchs im Rumpfektoderm vorhandenen Zellen dieses Typs vermehrt in die Tentakel abwandern und andererseits die Produktion der Desmonemen gesteigert wird. 6. Das Verhalten der Isorhizen wird durch den Verbrauch der Stenotelen nicht beeinflußt. 7. Die 3 Nematocyten-Typen weisen unterschiedlich lange Differenzierungszeiten auf: Isorhizen 1–3 Tage, Desmonemen 3–4 Tage, Stenotelen ca. 6 Tage. 8. Die Variabilität der Nematocyten in den Tentakeln und im Rumpfektoderm, der Zeitpunkt der Determination der zu Nematoblasten bestimmten Stammzellen (I-Zellen) sowie das konkordante Verhalten der Stenotelen und Desmonemen werden diskutiert.
    Notes: Summary The number of nematocytes in the tentacles and in the ectoderm of the body-column ofHydra attenuata Pall. shows a great variability. The variability of the nematocytes in the tentacles is manifested, not only if different individuals of the same clone, but also if various tentacles of the same polyp are compared. 2. The percentage of the different types of nematocytes in the tentacles and in the body-ectoderm shows a greater stability than the absolute numbers. A comparison of the percentage of differentiated nematocytes of the body-ectoderm with those of the tentacles shows that in these two regions of the polyp the different types of nematocytes are differently distributed. 3. By a combined chemical and mechanical stimulation of the tentacles, 90% of the stenoteles are discharged unlike the isorhizas and desmonemes, which cannot be brought to explosion under the same conditions. 4. The reaction of the polyp following the selective discharge of stenoteles shows three different phases: a) As a first, short-term reaction to selective discharge, differentiated stenoteles already present in the body-ectoderm move into the tentacles. b) In a second phase, the synchronous mitotic divisions of the already determinated groups of stenotele-nematoblasts are interrupted to enable earlier differentiation. c) In a third, long-term reaction, the production of new stenoteles is increased. This increased production occurs on one hand by supplementary determination of interstitial cells to stenotele-nematoblasts, and on the other hand by supplementary mitotic divisions, i.e. by increasing the number of nematoblasts per group. 5. The intense discharge of stenoteles has two effects on the desmonemes: It causes an increased number of differentiated desmonemes already present in the body-ectoderm during the discharge of stenoteles to migrate into the tentacles as well as an increase in the production of nematocytes of this type. 6. Neither the production nor the migration of the isorhizas are influenced by the discharge of stenoteles. 7. The times of differentiation of the three types of nematocytes are: Isorhizas 1–3 days, desmonemes 3–4 days, stenoteles about 6 days. 8. The variability of the nematocytes in the tentacles and in the ectoderm of the bodycolumn, the moment of determination of the interstitial-cells differentiating into nematoblasts as well as the co-ordinated behaviour of stenoteles and desmonemes are discussed.
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    Development genes and evolution 173 (1973), S. 46-59 
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    Description / Table of Contents: Zusammenfassung 1. Die Leber-, Blut- und Ovar-Proteine des ZebrafischesBrachydanio rerio wurden elektrophoretisch auf Celluloseacetat-Streifen (=Cellogel) und Polyacrylamidgel-Stäbchen (6%) aufgetrennt. Die Ontogenese der Proteinspektren wurde an 1, 4 und 6 Monate alten ♀♀ untersucht und mit geschlechtsreifen ♂♂ verglichen. Bei ♀♀ werden bestimmte Vitellogenese-korrelierte Muster beschrieben. 2. Zeitlich parallel zu dem cytologisch bekannten Aufbau des Dottersystems im Zuge der Oogenese erscheinen im Ovar 2 Protein-Fraktionen, die als Dottermaterial identifiziert werden können. 3. Die schon bei 4 Monate alten ♀♀ vorhandene erste Dotterfraktion besteht aus einem Glykoprotein mit bei pH 9 nur schwacher elektronegativer Ladung. Sie ist nur im Ovar nachzuweisen und stellt das endogene Dottermaterial dar. 4. Bei 6 Monate alten, geschlechtsreifen ♀♀ tritt zusätzlich im Ovarspektrum eine dann dominierende Bande auf, die aus einem stärker elektronegativ geladenen Lipoprotein besteht. Entsprechendes Material ist in geringerer Konzentration in der Leber und im Blut zu finden; diese Dottersorte besitzt demnach exogenen Charakter. Wahrscheinlicher Syntheseort ist die Leber. 5. Endo- und exogener Dotter haben im Polyacrylamidgel übereinstimmende elektrophoretische Laufweiten. 6. Der endogene Dotter ist sicher, der exogene wahrscheinlich ein ♀-spezifisches Protein.
    Notes: Summary 1. The soluble proteins of liver, blood, and ovary of the zebrafish,Brachydanio rerio, were separated by electrophoresis on cellulose acetate strips (cellogel) and polyacrylamide gels (6%). The ontogenesis of specific protein spectra was studied in females of 1, 4 and 6 months and compared with adult males. In females the development of distinct protein patterns correlated with the first vitellogenic cycle could be observed. 2. In the course of the incorporation of the yolk system (known from previous cytological investigations) 2 protein fractions identified as yolk materials appear in the ovary. 3. The first of these fractions is present already in ovary homogenates from females of 4 months. It consists of a glycoprotein with a small electronegative charge at pH 9. As this fraction is found only in the ovary, it represents endogenous yolk material. 4. In the 6 months old adult females an additional band appears in the ovary. This becomes the dominating fraction and was identified as an electronegatively charged lipoprotein. Fractions with corresponding properties are also found to a slight extent in the serum and can be extracted from the liver. That material therefore represents exogenous yolk. Probably the liver is the site of vitellogenin synthesis. 5. The endo- and the exogenous yolk substances have the same electrophoretic mobility in polyacrylamide gel. 6. The endogenous yolk is certainly, the exogenous probably, a female specific protein.
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    Development genes and evolution 173 (1973), S. 164-168 
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    Notes: Summary By following the lineage of the primordial germ cell and the mesoderm cells during the ontogeny of the gall midge,Heteropeza pygmaea, it has been determined that the nurse chamber of the polytrophic ovarioles of this insect is derived from the descendants of these cells. Such a dual origin for the nurse chamber of an insect ovary is the first of its kind to be reported.
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    Development genes and evolution 173 (1973), S. 169-182 
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    Notes: Summary Autoradiographic and histochemical techniques were used to determine whether chondrocytes continue to synthesize chondroitin sulfate or closely related compounds during morphological dedifferentiation of these cells in regenerating limbs of larvalAmbystoma. Forelimbs were amputated either through the mid-diaphysis or the distal epiphysis of the humerus and each animal was subsequently injected with Na2 35SO4 at an appropriate stage of regeneration. Incorporation of the isotope and metachromatic staining responses were used as indices of cell specialization. In autoradiographs of unamputated limbs, epiphyseal chondrocytes exhibited moderate sulfate incorporation, whereas isotope uptake was slight in diaphyseal regions. Accordingly, in early stages of regeneration, limbs amputated through the diaphysis showed a low level of sulfate incorporation by cartilage-derived cells; since these cells dispersed during blastema formation, they were not identifiable in later stages. When limbs were amputated through the epiphysis, the matrix here underwent slow dissolution and epiphyseal-derived chondrocytes and their progeny consequently remained identifiable as they contributed to the blastema. These cells continued to exhibit isotope uptake, even during early and middle stages of regeneration —results which support the idea of tissue-specific regeneration of cartilage. Further inspection of the stained autoradiographs revealed that in addition to chondrocytes and blastema cells derived from chondrocytes, fibroblast-like cells located lateral to the limb skeleton and seemingly derived from muscle or muscle-associated cells also exhibited a moderate label during certain stages in the restoration of the limb. In several respects isotope incorporation and related metachromatic responses by these two types of cells during blastemal and early redifferentiating stages of regeneration were seen to parallel results reported in the literature of histochemical and autoradiographic studies of differentiating chick fimb buds. These observations, which may be added to previous analogies concerning developing and regenerating limbs, suggest a similar mechanism of cytodifferentiation in the two systems. The possibility is also considered that the observed isotope uptake by cells of non-cartilaginous origin may indicate the synthesis of sulfated glycosaminoglycans which alfect cell interactions during the regenerative processes.
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    Development genes and evolution 173 (1973), S. 208-227 
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    Notes: Summary From our previous work we have put forward the hypothesis that cholinesterase activity in embryonic cells is related to morphogenetic movements. Therefore, the locomotory behavior of mesenchymal cells differentiating into cartilage by passing through a phase of Cholinesterase activity was analysedin vitro. Mesenchymal cores of chick limb buds stage 23/24 were partially disaggregated and cultured in plastic tissue culture dishes (Fig. 1). Within 31/2 to 5 days aggregates of mesenchymal cells differentiated into cartilage nodules surrounded by myoblasts (Figs. 2, 3 and 5). The cartilaginous nature of the nodules was confirmed by electron microscopy (Figs. 6 and 7). During the culture period serial photographs (24×24 mm) were taken (Tables 1–3). After formalin fixation the histochemical Cholinesterase reaction was carried out inside the culture dishes. Positive and negative cells were identified in the live serial photographs and their locomotory behavior was analysed. Initially the cells behaved like fibroblasts. Movements were regulated by contact inhibition, resulting in radial outward migration within the mesenchymal aggregates. In this first phase of development there was no cholinesterase activity. After 12 to 48 hours in culture however ChE-positive cells could be detected. Positive cells, appearing within a monolayer, detached from the bottom of the culture dish and crawled onto neighboring cells (Figs. 8a and b). In the periphery of the aggregates radial outward migration slowed down considerably. In the center short non-directional movements of positive cells could be observed, frequently leading to overlayering of cell bodies. In the third stage of development the ChE-positive cells stopped moving and transformed into cartilage cells (Fig. 9a and b). Finally, ChE-activity disappeared from the differentiated cartilage cells. From the difference in locomotory behaviour of negative and positive cells it is concluded that the appearance of Cholinesterase is accompanied by a change in the adhesive properties of the cells. An increase in cell adhesiveness enables the ChE-positive cells to detach from the bottom of the culture dish and to establish a new equilibrium of contact inhibition inside the cellular aggregates. This seems to be a prerequisite for the secretion of extracellular matrix and development of firm cell contacts. In vivo cartilage differentiation presumably also starts with an increase in cell adhesiveness in the presumptive cartilage cells. This provokes pseudopodial rearrangements leading to the condensation and demarkation of the cartilage anlagen. The change in adhesiveness is accompanied by Cholinesterase activity.
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    Development genes and evolution 173 (1973), S. 263-282 
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    Notes: Summary 1. Some aspects of the influence of position on regeneration have been examined by comparing regeneration from two different levels along the newt forelimb. 2. We have defined a series of stages of forelimb regeneration in the newt,Notophthalmus viridescens, in order to facilitate this study. 3. Limbs amputated at either a proximal level (through the humerus) or a distal level (through the radius and ulna) pass through the same stages at the same times after amputation. 4. The histological sequence of events of digit regeneration was compared with that of limb regeneration from a proximal level of amputation and was found to be the same. 5. In limbs amputated at either proximal or distal levels, the rate of elongation of regenerates is the same during the phases of dedifferentiation, blastema accumulation, and blastema growth. 6. During the phase of differentiation and morphogenesis, the rate of elongation of regenerates from the proximal level is significantly greater than that of regenerates from the distal level. 7. The total length of regenerates from proximal and distal levels along the limb is significantly different. 8. The results indicate that positional information does not influence the developmental sequence of events of limb regeneration, but that it does influence the rate of growth of the regenerate and the specification of the structures to be replaced.
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    Development genes and evolution 173 (1973), S. 346-354 
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    Notes: Summary Alkaline phosphatases and several dehydrogenases and oxidases separated by a microdisc electrophoresis technique have been studied during larval and early pupal development ofD. pseudoobscura salivary glands, fat body, hemolymph, body wall and whole body. Tissue-specific enzymes were observed and the qualitative differences occurring during the development are discussed.
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    Development genes and evolution 172 (1973), S. 349-354 
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    Notes: Summary Herold's organs from full-grown (T7) larvae ofEphestia kühniella were longitudinally bisected and both halves transplanted into a single T7-host. Three classes of results were observed after metamorphosis of the hosts: I. each of the two halves regenerated a complete genital organ, II. only one of the two halves regenerated, III. none of the two halves regenerated the missing parts (cf. Kroeger, 1959, Dewes, 1972). The onset of pupation of the hosts was delayed when one half (average delay 1.7 days) or both halves (average delay 2.5 days) underwent regeneration. No delay was observed in controls or when no regeneration took place (Table 1).
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    Development genes and evolution 173 (1973), S. 22-26 
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    Notes: Summary The teratogenic effects on chick embryos of chloroacetophenone, a specific sulfhydryl reagent, are known to be reversible by cysteine and glutathione. Dithiothreitol (Cleland's reagent) and thiomalic acid cannot ameliorate the -SH block syndrome. While cysteine and glutathione can elicit differentiation of axial structures in the post-nodal pieces of the chick blastoderm, dithiothreitol and thiomalic acid cannot do so. This finding seems to suggest that the naturally occurring thiols, cysteine and glutathione, play an important role in the primary organizer action.
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  • 88
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    Description / Table of Contents: Résumé 1. Pendant les six premiers jours de la régénération céphalique d'Eisenia fœtida on a mis en évidence plusieurs phases métaboliques se succédant dans le temps et comprenant: — une première et courte stimulation de la synthèse protéique (de 6 à 16 heures) — une première et courte stimulation de la synthèse de l'ARN (de 12 à 36 heures) — une deuxième stimulation longue et continue de la synthèse protéique (à partir de 16 heures) — une deuxième stimulation longue et continue de la synthèse de l'ARN (à partir de 48 heures) — enfin la phase S. 2. Les inhibiteurs de la synthèse d'ARN (actinomycine D et 5-fluorouracile) employés pendant la première stimulation d'ARN (0–36 heures) arrêtent complétement la régénération. Après 36 heures, un temps d'action de même durée entraine surtout des retards ou des anomalies dans la régénération. Ces derniers résultats sont aussi obtenus si l'on traite les animaux par ces inhibiteurs 48 heures avant l'opération. 3. Des courtes durées d'application (30 ou 48 heures après opération) d'inhibiteurs de la synthèse protéique (puromycine et cyclohéximide) n'arrêtent pas la régénération, mais provoquent des anomalies ou un fort retard de la régénération. 4. Au cours de la première stimulation de la synthèse protéique la fraction urée soluble (et tout particulièrement parmi elle les protéines ayant le plus faible poids moléculaire) est préférentiellement synthétisée. On pense que ces protéines sont caractéristiques de la phase précoce de 1'activation. 5. Pendant les trois premiers jours, l'ARN synthétisé est d'un type polydispersé. A 0, 24, 48 et 72 heures il y a une élaboration prépondérante d'ARN ribosomal et d'ARN transfert. Cependant à 16 heures (début de la première stimulation de la synthèse d'ARN) il existe une synthèse accrue des fractions les plus lourdes et de celles comprises entre les pics 18 S et 4 S. A 36 heures (avant le début de la deuxième stimulation de la synthèse d'ARN) on remarque aussi une production accrue d'ARN lourd.
    Notes: Summary 1. During the first six days of cephalic regeneration of Eisenia foetida several successive metabolic stages have been found as follows: a first and short stimulation of protein synthesis (from the 6th to the 16th hour), a first and short stimulation of RNA synthesis (from the 12th to the 36th hour), a second stimulation of protein synthesis, larger than the first and continuous (beginning at the 16th hour), a second, long and continuous stimulation of RNA synthesis (beginning at the 48th hour) and finally the S phase. 2. The regeneration is totally stopped by the RNA synthesis inhibitors (actinomycin D and 5-fluorouracil) when added during the first RNA stimulation (0–36 hours). If added after the 36th hour the same inhibitors give mostly delay or anomalies in regeneration. Same results are obtained when animals are treated during 48 hours before operation. 3. The use of protein synthesis inhibitors (puromycin and cycloheximide) for short times does not stop regeneration, but gives anomalies and long delays in regeneration. 4. An urea soluble fraction (and specially proteins with smaller molecular weight) is preferentially synthesized during the first stimulation of protein synthesis. It is postulated that these proteins are characteristic of the early phase of cellular activation. 5. The RNA synthesized during the first three days is polydispersed. The RNAs formed at 0, 24, 48 and 72 hours are mostly of ribosomal and transfer type. Nevertheless an increased synthesis of the heaviest fractions and those between 18 S and 4–5 S peaks, occurs at the 16th hour (beginning of the first RNA synthesis stimulation). An increased production of heavy RNA is also noticed at 36 hours before the beginning of the second RNA synthesis stimulation.
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    Development genes and evolution 173 (1973), S. 122-135 
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    Description / Table of Contents: Zusammenfassung 1. Die Metamorphose Planulae vonHydractinia echinata (Hydrozoa) wird durch eine pulsförmige (2–3 Std) Applikation der Ionen von Caesium, Rubidium, Lithium und Kalium ausgelöst. Mit Mischungen von Seewasser mit isoosmolaren Lösungen der Chloride dieser Ionen zeigen die Dosis-Wirkungskurven für K+, Rb+ und Li+ einen Optimumsverlauf. Dabei hat K+ den schmalsten Wirkungsbereich. Die Wirkungskurve von Cs+ ist sigmoid. Die halbmaximalen Dosen liegen bei 6 mval Cs+, 50 mval Rb+, 80 mval Li+ und 130 mval K+. 2. Eine K+-Stimulation ist ein Ouabain-insensitiver, vom Gibbs-Donnan-Verhältnis beherrschter Vorgang. Werden Lösungen appliziert, die nur K+, Ca++ und Saccharose enthalten, ist die optimale Wirkung stets einem invariablen Verhältnis von $$\left[ {{\text{K}}^{\text{ + }} } \right]:\sqrt {\left[ {{\text{Ca}}^{{\text{ + + }}} } \right]} = 40$$ zugeordnet, unabhängig von den aktuellen Konzentrationen. 3. Einer Cs+-Induktion liegen aktive, auf die Beteiligung eines Carriers hinweisende Vorgänge zugrunde. Eine indirekte Reaktionskinetik, die die Geschwindigkeit der larvalen Reaktion in Abhängigkeit von der Dosis als Maß der Kationenaufnahme nimmt, liefert Michaelis-Menten-artige Sättigungskurven. Reduktion des externen Ca++- und Na+-Gehalts und ebenso Applikation des Glutathion-oxidierenden Agens Diamide erhöhen die Effektivität von Cs+. Die Form der Wirkungskurve nähert sich einer rechteckigen Hyperbel und die halb-maximale Cs+-Konzentration wird zu tieferen Werten verschoben. Durch gleichzeitige Applikation von Ouabain geht die Induktionswirkung von Cs+, Rb+ und Li+ (nicht die von K+) verloren. Diese Befunde erlauben es, die Primärwirkung dieser Ionen als Stimulation der Na+-K+-Transport-ATPase zu interpretieren. 4. Die Auslösung der Metamorphose durch monovalente Kationen geschieht somit über Änderungen Membran-gebundener Funktionen. Dies trifft ebenso für die Bakterien-induzierte Metamorphose zu.
    Notes: Summary 1. The metamorphosis of the planulae ofHydractinia echinata (Hydrozoa) can be induced by a pulse-type (2–3 hrs) exposure to the ions of caesium, rubidium, lithium, and potassium. With mixtures of seawater with isoosmolar solutions of the chlorides of these ions the dose-response curves for Rb+-, Li+-, and K+-stimulation display optima peaks, the smallest effective range being shown by K+. The Cs+-curve is sigmoid shaped. The half-maximal doses are 6 mval Cs+, 50 mval Rb+, 80 mval Li+, and 130 mval K+ respectively. 2. Potassium-induced stimulation is an ouabain-insensitive event governed by the Gibbs-Donnan principle. With solutions containing only K+, Ca++, and Sucrose the optimal efficacy is always related to an invariable ratio of $$\left[ {{\text{K}}^{\text{ + }} } \right]:\sqrt {\left[ {{\text{Ca}}^{{\text{ + + }}} } \right]} = 40$$ , regardless of the actual concentrations employed. 3. The Cs+-induction is based upon active events which indicate the involvement of a carrier-like system. Indirect reaction kinetics taking the velocity of the larval response versus the dose as measure of cation uptake yield Michaelis-like saturation curves. Reduction of external calcium and sodium as well as application of the glutathione oxidizing agent diamide enhance the efficacy of Cs+. The shape of the response curve becomes closer to a rectangular hyperbola and the half-maximal concentration is shifted towards lower values. The inducing power of Cs+, Rb+, and Li+ (but not of K+) is abolished by ouabain (1 mM). These findings give evidence that the relevant ions act by stimulation of the Na+/K+-transport ATPase. 4. Thus, induction of metamorphosis by monovalent cations is due to alterations of membrane-bound functions. This applies to bacteria-induced metamorphosis as well.
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  • 90
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    Description / Table of Contents: Résumé Chacun des stades de l'ovogenèse: prévitcllogenèse, vitellogenèse protéique, élaboration des glucides, maturité, se déroule en présence d'un taux hormonal déterminé. Pendant les stades de prévitellogenèse et de vitellogenèse protéique (taux hormonal élevé), le nucléole se compose de trois zones concentriques: un centre fibrillaire, une couronne intermédiaire fibrillaire et un cortex granulaire. Au cours du stade d'élaboration des glucides, qui survient après une diminution rapide du taux d'hormone, une nouvelle organisation nucléolaire apparaît. Le nucléole est alors constitué de plages fibrillaires dispersées dans un composant fibrillo-granulaire. Durant le stade de maturité (taux hormonal nul), le matériel nucléolaire se ségrège en deux hémisphères puis se fragmente. L'effet de la suppression expérimentale de l'action cérébrale a été envisagé. Dans les ovocytes en phase de vitellogenèse protéique, l'absence du facteur hormonal entraîne rapidement l'apparition d'une vacuole nucléolaire de grande taille. La vacuole se résorbe ensuite et le nucléole reprend un aspect compact. La fin de l'évolution expérimentale est marquée par la ségrégation des constituants f ibrillaire et fibrillo-granulaire du nucléole. L'étude chronologique des modifications survenant dans les différents sites cellulaires montre que les conséquences de la suppression de l'action endocrine du cerveau sont observées au niveau du nucléole bien avant d'être décelables dans le cytoplasme. Ces résultats sont discutés en fonction des données actuelles sur la régulation hormonale des synthèses d'ARN.
    Notes: Summary Each stage of oogenesis: previtellogenesis, proteic yolk elaboration, carbohydrates synthesis, maturity, take place under a given hormonal rate. During the previtellogenesis and protein yolk elaboration stages (high hormonal rate), nucleolus is composed of three concentric zones: a fibrillar center, a fibrillar intermediate belt and a granular cortex. During the carbohydrates synthesis stage, which occurs after a rapid decrease of the hormonal rate, a new nucleolar organization appears. Nucleolus is then composed of fibrillar places scattered among a fibrillo-granular component. During the maturity stage (very low hormonal rate), the nucleolar material segregates into two hemispheres, then breaks up. The result of removal of cerebral activity was considered. In oocytes undergoing protein yolk elaboration, the absence of hormone rapidly produces the development of a large nucleolar vacuole. Then, vacuole decreases and nucleolus shows again a compact shape. The end of the experimental evolution is marked by the segregation of the nucleolar fibrillar and fibrillogranular components. Chronological study of the modifications occuring at the different cellular regions shows that the consequences of removal of hormonal activity are seen at the nucleolar level in advance of being detectable in cytoplasm. These results are discussed accordingly present notions about hormonal regulation of RNA synthesis.
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    Development genes and evolution 173 (1973), S. 249-262 
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    Description / Table of Contents: Zusammenfassung Nach Allatektomie im IV. Larvenstadium werden die Versuchstiere gemeinsam mit unbehandelten Kontrolltieren in 18° oder 28° C gehalten. Anschließend werden die Karotinoide, das Biliverdin und das Xanthommatin des Körpers unter Ausschluß der Augen, des Dar-mund des Ovarinhaltes bestimmt. 1. Der Biliverdingehalt und der absolute Karotinoidgehalt sind im untersuchten Bereich weder bei den Kontrolltieren noch bei den Versuchstieren merklich temperaturabhängig. 2. Der relative Karotinoidgehalt steigt nach der Operation vorübergehend geringfügig an, sinkt dann aber unter denjenigen der Kontrolltiere. Diese Wirkung kann mit der Eibildung bei den vorzeitig adult gewordenen operierten Tieren zusammenhängen. 3. Der Biliverdingehalt sinkt bei der Operation durch den Blutverlust nur vorübergehend ab und steigt wieder auf den relativ zum Körpergewicht normalen Wert an. Die Stabheuschrecken können demnach ohne Corpora allata Biliverdin bilden. 4. Der Xanthommatingehalt nimmt in der Wärme zu. Diese Zunahme bleibt nach Entfernung der C. allata aus. Diese Wirkung hängt möglicherweise mit der vorzeitigen Metamorphose der operierten Tiere zusammen, da Imagines nur wenig Ommochrom bilden. 5. Nach Lackierung der unteren Augenhälften bilden auch Tiere ohne Corpora allata vermehrt Xanthommatin. — Die optisch gesteuerte Ommochrombildung bei der morphologischen Farbanpassung ist demnach unabhängig von den Corpora allata.
    Notes: Summary Indian stick insects were deprived of their Corpora allata during the 4th larval instar and kept together with untreated control animals in 18° or 28° C. The amounts of Carotenoids, Biliverdine and Xanthommatine of the body —excluding eyes, gut and ovary — have been determined. 1. Neither in operated animals nor in normal controls there were marked temperaturedependent differences in Biliverdine and in absolute Carotenoid content. 2. The relative Carotenoid content with respect to body weight increased in operated animals temporarily. Afterwards it decreased beneath that of control animals. This may be an effect of the deposition of Carotenoids into the ova, as the allatectomized animals undergo premature metamorphosis. 3. The Biliverdine content decreases after operation due to blood loss. Later on it increases again, showing that Biliverdine-synthesis is not dependent on the presence of Corpora allata. 4. Higher temperature increases the Xanthommatine content in normal animals but not in animals deprived of their Corpora allata. This may also be an effect of premature metamorphosis, as ommochrome synthesis is reduced in adult animals. 5. Black covering of the ventral halves of the eyes increases the ommochrome content even in the animals without Corpora allata. This indicates, that the morphological colour adaption is not dependent on the presence of Corpora allata.
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    Development genes and evolution 173 (1973), S. 333-345 
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    Notes: Summary Eye-antennal and ventral mesothoracic (midleg) disks of 7 1/2 days old, mature larvae ofD. hydei, homozygous for the lethal genelpl (lethal-polyploid), have been transplanted into 7 1/2 or 4 1/2 days old larval wildtype hosts. The morphology oflpl disks shows a variation of damage ranging from complete absence or strongly reduced anlagen to normal sized disks. Transplanted disks are able to undergo metamorphosis and to differentiate adult structures. The inventory of structures formed varies individually and is always less complete than differentiations obtained from wildtype controls, but the topographical arrangement appears to be normal. Even after a prolonged stay in the larval hosts, proliferation processes are rare, and transdetermination was not observed. The results are discussed, and it is suggested that the mutant effect which appears to be cell autonomous but not fully penetrant causes a mitotic disturbance which, at a low incidence, affects randomly the cell divisions of mitotically active tissues throughout larval life.
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    Development genes and evolution 173 (1973), S. 319-332 
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    Notes: Summary Dorsal (D), lateral (L and R), and ventral (V) portions of the endoderm of blastulae ofAmbystoma mexicanum of different age (stages 8+ to 10−) were combined with ectodermal caps of stage 8+ blastulae. All V and most L and R portions induced only ventrocaudal mesodermal structures — “ventral” type of mesoderm induction. Almost all D portions induced much more voluminous structures of predominantly axial character — “dorsal” type of mesoderm induction. The difference in mesoderm-inducing capacity of the dorsal as against the lateral and ventral endoderm is probably purely quantitative in character. The dorsal endoderm exhibits a pronounced dominance in mesoderm-inducing capacity. During the early symmetrization of the amphibian egg it is apparently especially the presumptive dorsal endoderm that becomes endowed with strong mesoderm-inducing properties. A comparison of the results obtained with endodermal portions of blastulae of different age showed that the mesoderm-inducing capacity first begins to decline in the dorsal endoderm (around stage 9), subsequently in the lateral, and finally in the ventral endoderm (at stage 10−). At stage 10− the dorsal endoderm no longer has mesoderm-inducing capacities. In the recombinates there is a striking correspondence between the regional differentiation of the mesoderm and that of the endoderm. The latter differs markedly from the presumptive significance of the various endodermal regions in the normal embryo. Primordial germ cells, which constitute a characteristic component of the “ventral” type of mesoderm induction, can be induced not only by ventral, but also by lateral and to some extent even by dorsal endoderm. The development of primordial germ cells from the ectodermal component of the various recombinates indicates that in the urodeles the origin of the primordial germ cells differs markedly from that in the anurans.
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    Development genes and evolution 172 (1973), S. 231-257 
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    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. BeiEphestia kühniella wurde die Ontogenese und Kontrolle stadienspezifischer Veränderungen in den Spektren der löslichen Proteine von Hämolymphe und Fettkörper untersucht. 2. Die Gesamtproteinkonzentration der Hämolymphe unterliegt während der postembryonalen Entwicklung erheblichen Schwankungen. Sie steigt im vorletzten Larvenstadium an und fällt während der Häutung wieder ab. Im letzten Raupenstadium nimmt sie bis zum Beginn der Vorpuppenphase um das Dreifache zu und erreicht hier mit etwa 100 mg/ml das Maximum. Nach einem Abfall nach der Vorpuppenphase tritt in der Puppenruhe ein neuer Gipfel auf. Zu Beginn des Imaginallebens beobachtet man ein Minimum. Aus Messungen des Hämolymphvolumens, die während der letzten Raupenhäutung und im Altlarvenstadium vorgenommen wurden, ließ sich die absolute Blutproteinmenge errechnen. Sie folgt im wesentlichen der Konzentrationskurve. 3. Mittels Cellogelelektrophorese lassen sich die Hämolymphproteine junger Vorpuppen in 10 verschiedene Fraktionen auftrennen. Neben gelben und blaugrünen Chromoproteiden findet man Lipo- und Glycoproteide. In Ganztier- und Organhomogenaten wurden Blutproteine aufgrund ihrer elektrophoretischen Beweglichkeit und ihrer immunologischen Eigenschaften identifiziert. 4. Während der Entwicklung zeigen die einzelnen Hämolymphproteinfraktionen zum Teil eine ausgesprochene Stadienspezifität und individuelle Konzentrationsschwankungen. Zwei Banden (2 und 3) galt wegen ihres extrem unterschiedlichen ontogenetischen Verhaltens bei weiteren Untersuchungen das Hauptinteresse. 5. Im Verlauf der Vorpuppenphase verschwindet die Bande 2 fast völlig aus der Hämolymphe, während 3 kaum reduziert wird. Der Fettkörper akkumuliert gleichzeitig Zone 2 in wesentlich höherem Maße als 3. Die zeitliche Korrelation dieser Veränderungen in beiden Organen und die Tatsache, daß die Konzentrationen der Fraktionen 2 und 3 in Ganztierhomogenaten dabei gleich bleibt, spricht für eine spezifische Aufnahme und Anreicherung von Blutproteinen durch den Fettkörper. In Darmhomogenaten wurden beide Fraktionen nicht angetroffen. 6. Während der Metamorphose bleibt die Konzentration der Bande 2 in Ganztierhomogenaten zunächst konstant, obwohl sie parallel zur Histolyse des Fettkörpers im Blut ein neues Maximum durchläuft. Zone 3 nimmt in Ganztierhomogenaten und Hämolymphe allmählich ab. In der Imago sind beide Fraktionen nicht mehr nachzuweisen. 7. Durch Thoraxligaturen lassen sich in den Abdomina von L6T7-Raupen (diese stehen kurz vor der Vorpuppenphase) das Verschwinden der Bande 2 aus der Hämolymphe und die normalerweise damit verbundene Akkumulation dieser Fraktion im Fettkörper verhindern. In isolierten Hinterenden von jungen Vorpuppen (A2) laufen diese Prozesse nur partiell ab. 8. Durch Injektion von Ecdyson (0,125–1,000 μg) kann in den isolierten Abdomina von A2-Vorpuppen eine vollständige Verarmung der Hämolymphe an Bande 2 induziert werden. 9. Die Akkumulation von Blutproteinen im Fettkörper ist mit dem Erscheinen von histologisch nachweisbaren Albuminoidstrukturen korreliert.
    Notes: Summary 1. The ontogenesis and the control of stage specific changes in the spectra of the soluble proteins of the haemolymph and the fat body ofEphestia kühniella were examined. 2. The total protein concentration of the haemolymph is subject to considerable fluctuations during postembryonal development. It rises during the 5th larval stage and then drops again during molting. During the 6th larval stage up to the beginning of the prepupal stage it maximizes at 3 times its original amount at a concentration of 100 mg/ml. After a decrease during the prepupal phase a new peak occurs during the pupal stage. In the young imago a minimum is observed. From measurements of the haemolymph volume during the last larval molt and the last larval stage the absolute amount of blood protein could be calculated. In general it follows the concentration curve. 3. By means of cellogel electrophoresis the haemolymph proteins of young prepupae can be separated into 10 different fractions. In addition to yellow and bluegreen chromoproteids, lipo- and glycoproteids can be found. In homogenates of whole animals and organs blood proteins were identified by means of their electrophoretic mobility and their immunologic properties. 4. During development some of the haemolymph protein fractions show a distinct stage specificity and individual fluctuations of concentration. In further investigations two bands (i.e. 2 and 3) were of main interest because of their extremly different ontogenetic fates. 5. In the course of the prepupal phase band 2 disappears almost completely from the haemolymph, whereas 3 is hardly reduced. At the same time the fat body accumulates zone 2 much more than 3. The temporal correlation of these changes in both organs and the fact that the concentration of the fractions 2 and 3 in homogenates of whole animals does not change at the same time indicates a selective sequestration and accumulation of blood proteins by the fat body. In gut homogenates neither of the two fractions was found. 6. At the beginning of metamorphosis the concentration of band 2 in homogenates of whole animals remains constant. But in the blood it passes a new maximum synchronously to the histolysis of the fat body. Zone 3 slowly decreases in homogenates of whole animals and haemolymph. In the imago neither of the two fractions was detected. 7. By means of thoracic ligatures in the abdomina of L6T7-larvae (shortly before the prepupal stage) the disappearence of the band 2 from the haemolymph and the accumulation of this fraction in the fat body can be prevented. Both connected processes take place in isolated abdomina of young prepupae (A2) but not to the same intensity as in normal development. 8. By injecting ecdysone (0.125–1.000 μg) a complete impoverishment of the haemolymph of band 2 can be induced in the isolated abdomina of A2 prepupae. 9. The accumulation of blood proteins in the fat body is correlated with the appearence of histologically provable albuminoid granules.
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  • 95
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    Development genes and evolution 172 (1973), S. 303-316 
    ISSN: 1432-041X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Oral application of farnesyl methyl ether (FME), which allows for a continuous supply, inhibited the pupal differentiations of the integument. Animals fed during the course of the last larval instar reached the stage of grown-up feeding larvae, but did not enter the pharate pupal phase. By this way pupation could practically be delayed for any length of time. When the FME was administered from the first day of this instar a supernumerary larval molt occurred in some animals. A further molt, however, did not take place. An earlier treatment increased the number of superlarvae. Beginning the exposure to FME at the end of the last larval instar, some larval-pupal intermediates could be obtained with predominantly larval characteristics. When the continuous application was discontinued and the animals were transferred to FME-free food, a normal pupation took place. In the testes the metamorphosis changes of fusion and torsion were similarly inhibited by the juvenile hormone analogue. Furthermore, FME influenced testis growth. A dilution series was tested on two age groups (1- or 7-day-old last instar larvae). On transforming the data into the logarithms, two negative linear dose-response relationships were obtained. The regression analysis showed that both sets of data fitted simple straight-line models. The regression curves could be regarded as parallel whereby the older animals had higher testis size values at a given dose. However, compared with the size at the beginning of the FME-application, in the older animals a real decrease in volume took place. When the animals were transferred to untreated food, their testes became normal in size, fused and twisted. The dose-response relationship could be verified in vitro. Here too, a negative linear regresion of the log (testis size) on the log (FME-dose) was found. The regression coefficient did not differ significantly from that calculated from the in vivo data. Hence, FME acts directly on the testis sheath and does not control the organ size by alterations of the hemolymph. Testes will fuse autonomously if they have passed the critical period of this process. Culturing organs after this period on a FME-containing medium, they fused after one day despite the presence of the juvenile hormone analogue. However, with further incubation these fused partners separated. Testes which were already fused at the beginning of the incubation remained together. This indicates that there is a period of modifiable surface properties of the testes during which a fusion can be reversed by FME. The process of torsion does not show such a reversibility.
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  • 96
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Das schlauchförmige Ovar vonOdontotermes badius wird in seiner ganzen Länge vom Ovidukt durchzogen, in den von allen Seiten annähernd 3 000 Ovariolen münden. Bei einem schwärmenden Weibchen sind nur die ersten 5–7 Ovariolen in ihrer Entwicklung soweit fortgeschritten, dass wenige Tage nach dem Schwärmen und Abwerfen der Flügel Eier abgelegt werden können. Die übrigen Ovariolen sind noch in einem frühen Stadium der Entwicklung. Es dauert mehrere Jahre bis alle Ovariolen das Stadium der vollen Reife erreicht haben. Zur imaginalen Entwicklung: Die Ovariolen nehmen an Länge zu. Die Zwischenräume zwischen ihnen werden grösser. Der Ovidukt wird länger und breiter. Die Längenzunahme der Ovariolen wird nicht beendet, sobald sie das Stadium der ersten Reife erreicht haben. Es besteht eine Beziehung zwischen dem Wachstum des Ovars und der weiteren Verlängerung der Ovariolen. Mit der Verlängerung der Ovariolen nehmen zu: Die Grösse des Germariums, die Zahl der Oocyten in der Wachstumsphase und die Zahl der zu gleicher Zeit Dotter-einbauenden Oocyten. Zu einer Neubildung von Ovariolen kommt es jedoch in der Imago nicht. Die Entwicklung setzt Ovarvorn ein. Die vorderen Ovariolen erreichen zuerst ihre maximale Länge. Die Ovariolen entwickeln sich jedoch nicht gleichmässig. Im Zusammenhang mit dem Wachstum des Ovars nehmen alle Organe des Abdomens an Grösse zu. Dabei kann es sich um Zellteilungen, Vergrösserung von Zellen und um Neubildung von Organen handeln. Im gleichaltrigen Männchen kommt es dagegen nur zu einer Hoden-Hypertrophie und zu einer Verlängerung des Mitteldarms.
    Notes: Summary On the growth of the imaginal ovary in connexion with the physogastric enlargement ofOdontotermes badius Haviland (Insecta, Isoptera). The tubelike ovary ofOdontotermes badius is penetrated at full length by the oviduct into which approximately 3,000 ovarioles are discharging from all sides. In the case of a swarming female only the anterior 5 to 7 ovarioles are sufficiently mature to ovulate a few days after dropping of the wings. The rest of the ovarioles are in very early stages of development and very short in length and it takes several years before all of the ovarioles become fully mature. The imaginal development of the ovary proceeds as follows: The ovarioles lengthen and the distances between them become larger while the oviduct becomes longer and wider. When an ovariole reaches the first stage of maturation and gives off mature oocytes the lengthening of the ovariole is incomplete. There is a correlation between the growth of the ovary and the further lengthening of an ovariole. Also the lengthening, of the ovarioles is correlated with an increase in number of germarium-cells, in the number of oocytes of the growing stage and in the number of occytes which deposit yolk simultaneously. But there is no new formation of ovarioles during the whole imaginal life. The development of the ovarioles is phased. Those at the anterior pole are starting first and consequently reaching the maximum length sooner than the ovarioles at the hind part of the ovary. All the ovarioles start to develop but some of them develop more slowly and reach the maximum length later. Growth of the ovaries is made possible by the enlargement of the abdomen. In connexion with this enlargement there is growth of all abdominal organs. We must distinguish between growth by cell division alone (e.g. epidermis, connectives, midgut, heart tube), by widening of the epithelium cells predominantly (e.g. spermatheca, accessory glands) and by formation of new tissue (e.g. malpighian tubules).
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  • 97
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Des enregistrements de température ont été effectués depuis le moment où de jeunes reines deBombus (Pyrobombus) impatiens se sont enfouies dans le sol jusqu'au moment où elles sortent de terre au printemps suivant. Les relations entre l'émergence, la radiation solaire et la température ont fait l'objet d'une analyse statistique.
    Notes: Summary Temperature records were kept from the time the new queens ofBombus (Pyrobombus) impatiens burrowed into the soil until they emerged the following spring. Statistical analysis is presented on the relationship of solar radiation and temperature as they affected emergence.
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  • 98
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    Insectes sociaux 20 (1973), S. 189-203 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé ChezStegodyphus sarasinorum Karsh, l'état adulte est atteint après 12 stades. Les caractères sexuels secondaires deviennent visibles au douzième. Il y a seulement une génération par an. Normalement, durant sa vie, une femelle ne tisse et soigne qu'un seul cocon. On a analysé les différents aspects de la bionomie et du comportement de cette araignée sociale, c'est-à-dire l'architecture du nid, réparation de la toile, rythme d'activité, nourriture et comportement alimentaire, densité de population aux différents stades, sex-ratio, comportement sexuel, comportement maternel, dispersion et fondation de colonies. En plus du nourrissage de ses enfants au deuxième stade par régurgitation et apport de proies capturées, la mère s'offre finalement comme réserve vivante de nourriture pour ses enfants qui pompent la lymphe et elle meurt lentement. De nouvelles colonies apparaissent par migration sur fils de soie ou bien de jeunes du quatrième au neuvième stade à différents moments de la colonie, ou bien de femelles fécondées seules. Dans une deuxième méthode de fondation de colonie, la migration des jeunes du quatrième au huitième stade se fait seule ou en petits groupes par production de fils de soie et transport aérien.
    Notes: Summary InStegodyphus sarasinorum Karsch the adult stage is attained after twelve instars. The secondary sexual characters become manifest in the twelfth instar. There is only one generation per year. Normally only one cocoon is made and taken care of by a fertilized female during her life-time. The various aspects of the bionomics and behaviour of this social spider, viz., the nest architecture, repair of webs, activity rhythm, food and feeding behaviour, population density at different stages, sex-ratio, sexual behaviour, maternal behaviour, dispersal and colony foundation, are discussed. Besides feeding her young ones during the second instar by regurgitation and by providing them with captured prey, the mother spider finally offers herself as a living food depot for her young ones which suck out her body fluids and she slowly dies. New colonies are formed after emigration over silken threads by either groups of spiderlings at various times in colonies during the fourth to ninth instars (sociotomy), or by individual fertilized females. In a second method of colony foundation, emigration of spiderlings of fourth to eighth instars takes place either by individuals or by small groups by means of silken threads produced and wafted in the wind (aerial navigation).
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  • 99
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé On a fait des recherches sur la distribution de l'activité cellulolytique dans les intestins des termites ouvrièresT. trinervoides. 70% à peu près de l'activité totale a lieu dans l'intestin moyen, dont environ 40% dans la paroi de l'intestin moyen. L'aspect et la distribution des bactéries intestinales sont décrits. On en conclut que, dans ces espèces, la cellulase est synthétisée par les termites elles-mêmes.
    Notes: Summary The distribution of cellulase activity in the guts of workers of the termiteT. trinervoides was investigated. Approximately 70% of the total activity was found in the midgut and about 40% oif this occurs in the midgut wall. The appearance and distribution of gut bacteria is described. It is concluded that, in this species, the cellulase is synthesised by the termites themselves.
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  • 100
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The Argentine ant (Iridomyrmex humilis Mayr.) is of great economic importance on the French Riviera, not only as a house pest, but also because it does much harm to the plants in the fields by maintaining colonies of homopterous insects for their honeydew. For two successive years, we have been studying the seasonal behaviour and the evolution of colonies of this species in Antibes area. A comparison between the annual biological cycles of societies nesting in very different materials, such as wood or soil, shows the direct effect of some climatic factors (specially temperature and dampness) on their ethology and dynamics of population. For this imported species, the choice of suitable nesting sites according to the season and the possibility of supplying the nests with food even in winter are two factors of adaptation to unfavorable natural conditions. Besides, the polygyny of the colonies, the abundant fecondity of the queens and the rather weak hostility between workers of adjacent nests account for the fact thatI. humilis have widely spread and progressively taken the place of the native species in our region.
    Notes: Résumé La fourmi d'Argentine,Iridomyrmex humilis Mayr, a une grande importance économique sur la Côte d'Azur, non seulement en tant que fléau domestique, mais aussi par sa nuisibilité dans les cultures où elle entretient des colonies d'Homoptères pour leur miellat. Pendant deux années consécutives, nous avons étudié le comportement saisonnier et l'évolution des colonies de cette espèce dans la région d'Antibes. La comparaison du cycle biologique annuel de sociétés nidiflant dans des substrats très différents (bois et terre) fait apparaître l'action directe de facteurs climatiques (principalement la température et l'humidité) sur l'éthologie et la dynamique de population. Le choix des sites de nidification appropriés suivant la saison et l'approvisionnement des nids même en hiver sont deux facteurs d'adaptation aux conditions naturelles défavorables de cette espèce importée. Egalement, la polygynie des colonies, la fécondité importante des reines et la faible hostilité entre ouvrières de nids voisins, expliquent la pullulation d'I. humilis et le remplacement progressif des espèces autochtones dans notre région.
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