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  • 1
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The mound builderMacrotermes michaelseni forages in Kenya semi-arid pastures. Each colony (4/ha) utilizes 130 to 600 m2 in average per month. The distribution of foraging holes 22 000 to 50 000 per nest) shows an overall spatial activity. The 24h foraging activity is mainly nocturnal and the seasonal variation presents three peaks per year. This activity depends partly on temperature and rainfall but the internal economy (sexual brood production within the colony) plays a decisive role.
    Notes: Resume Macrotermes michaelseni est un constructeur de termitières épigées qui récolte en strate herbacée dans les pâturages semi-arides du Kenya. Chaque colonie (4/ha) exploite en moyenne 130 à 600 m2 par mois. La répartition des orifices de récolte (22 000 à 50 000 par colonie) démontre que l'ensemble du milieu est utilisé. On envisage la variation journalière de l'activité de récolte (essentiellement nocturne) ainsi que sa périodicité saisonnière (3 maximums annuels). Cette activité est partiellement reliée à la température et aux pluies, mais l'économie interne des colonies (production du couvain de sexués) est aussi déterminante.
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  • 2
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    Insectes sociaux 28 (1981), S. 341-342 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Nestgründung von einer Arbeiterin der japanischen Falten WespePolistes chinensis antennalis wurde im Juni 1979 beobachtet. Diese Arbeiterin ausschlüpft im Juni 1979 aus einem anderen Nest und reparierte ein verlassenes Nest und zog darin einige Larven aus. Diese ist die erste Entdeckung der Nestgrüdung von einer Arbeiterin in der Unterfamilie Polistinae.
    Notes: Summary The nest foundation by a single worker of the Japanese paper waspPolistes chinensis antennalis was observed in July, 1979. This worker had emerged from another nest in June 1979, and repaired an abandoned nest and reared some larvae there. This is the first discovery of nest foundation by a worker in the subfamily Polistinae
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  • 3
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary The present work follows the study ofMacrotermes michaelseni foraging activities (Lepage, 1981) and deals with its food requirements. The yearly food offtake ranges between 800 and 1500 kg/ha. The harvest is 25 to 30% below in lean year (1976). Termites and large mammals offtakes are similar but they take place at different times of the ecosystem cycle: rainy season for mammals and dry season for termites.Macrotermes would prefer grass litter on the ground if available, but can switch to standing crop as the ecosystem becomes more arid. From this work it is possible to understand howMacrotermes could be a pest in these pastures.
    Notes: Resume Cette étude envisage la prise de nourriture du termiteMacrotermes michaelseni en strate herbacée et complète les observations rapportées précédemment sur le cycle de récolte du termite (Lepage, 1981). Le prélèvement varie de 800 à 1500 kg/ha/an et il est de 25 à 30% inférieur lorsque l'année est déficitaire en pluies (1976). Cette récolte est comparée à l'action des grands Mammifères herbivores présents sur le lieu de l'étude: les quantités globales (herbe et litière) sont du même ordre. Mais l'impact sur l'écosystème n'intervient pas au même moment: saison des pluies pour les Mammifères, saison sèche pour les termites.Macrotermes préfère la litière graminéenne au sol mais consomme progressivement l'herbe sur pied à mesure que l'écosystème devient plus aride. Il est possible de comprendre, d'après ces observations, commentMacrotermes peut devenir nuisible pour ces pâturages semi-arides.
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  • 4
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    Insectes sociaux 28 (1981), S. 347-352 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Ungefähr 18% der Arbeiterinnen vonLasioglossum zephyrum werden unter natürlichen Freilandbedingungen begattet. In der Gefangenschaft variiert die Bereitschaft der Weibchen zur Begattung mit dem Alter und dem Kastenzustand: 1) Von anderen Weibchen isolierte Weibchen paarten sich zu 69% innerhalb von drei Tagen nach dem Schlüpfen. 2) In Nestgruppen von je sechs Bienen paarten sich alle Königinnen, jedoch nur 7,7 % aller Arbeiterinnen. 3) Nach künstlicher Entfernung der Königin verpaarten sich die Ersatzköniginnen in allen von zehn Fällen. Diese Ersatzköniginnen waren alle vorher in Gegenwart der alten Königin unverpaart. 4) In einer Kolonie von fünf Bienen paarten sich alle drei Ersatzköniginnen nachdem der Reihe nach die jeweilige Königin entfernt worden war. Gleichzeitig wurden keine der jeweiligen Restarbeiterinen begattet. Diese Ergebnisse zeigen an, dass die Königin die Paarungsbeitschaft der Arbeiterinnen auch ausserhalb des Nestes inhibiert. Es erscheint möglich, dass sich Inhibition durch eine Königin nicht nur auf die Grösse der Ovarien von Arbeiterinnen auswirkt.
    Notes: Summary About 18 percent ofLasioglossum zephyrum workers mate in the field. In the laboratory female mating receptivity varied with age and caste: 1) sixty-nine percent of bees less than 3 days old mated when kept isolated from other females, 2) in six-bee colonies all of the queens, but only 7,7 percent of their workers, mated, 3) in queen removal experiments involving 10 colonies, all the replacement queens mated (these same individuals were not receptive to mating as workers), 4) in one colony of 5 bees, consecutive queen removal showed that each of the four bees identified as the queen mated, while none of the remaining workers did so. The results indicate that queen inhibition governs behavior of the workers even outside the nest. The inhibition may involve more than differences in ovarian size.
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  • 5
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    Insectes sociaux 28 (1981), S. 353-370 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary Workers ofMyrmica rubra cluster around living queens from their own colony. Workers also cluster around these same queens after they are killed and kept for one or two hours. The suggestion is that the factors causing these aggregations are at least partly chemical, for dead queens are unable to give movement or acoustical signals. Also, the form of the queens'body is unable to induce the clustering response. The chemical signals causing aggregation, emitted by the queen, are not very volatile and/or they are well adsorbed by her cuticle. They oxidise rapidly after 3–4 hours exposure to the air and they continue to denature, losing their ethological activity, for the subsequent 2–3 days. They deteriorate when warmed to a temperature of 50°C for a few minutes. Organic solvents denature them rapidly and may extract them whereas distilled water has no effect upon them. The chemical factors are uniformly distributed over the external surface of the queen's body and it seems that they are not produced by the metapleural glands. The experiments, producing the above results, are detailed and discussed raising questions and hypotheses that we will consider in future work.
    Notes: Resume Les ouvrières deMyrmica rubra s'agrègent autour de reines indigènes vivantes, et de ces mêmes reines mortes depuis 1 ou 2 heures. Les facteurs responsables de ces agrégations sont, au moins partiellement, de nature chimique. Ils ne sont ni gestuels, ni acoustiques, et la forme du corps des reines est incapable, à elle seule, d'agréger les fourmis. Les facteurs chimiques agrégatifs propres aux reines sont peu volatiles et/ou bien adsorbés sur la cuticule des reines. Ils s'oxydent à l'air au bout de 3 ou 4 heures puis se dégradent encore d'une autre manière, progressivement, au cours du temps. Un passage de quelques minutes à une température voisine de 50°C les altère. Les solvants organiques, mais non l'eau distillée, les dénature rapidement et les extraient peut-être. Enfin, ces facteurs chimiques se répartissent uniformément sur toute la surface externe du corps des reines, et ils ne semblent guère provenir des glandes métapleurales. Après avoir détaillé nos travaux, puis discuté des renseignements acquis, nous posons des questions et hypothèses à envisager dans la suite de notre étude.
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  • 6
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume La «fourmi de feu»,Solenopsis invicta Buren, a trois principaux groupes fonctionnels d'ouvrières: les fourrageuses, les «stockeuses de réserves» et les nourrices. En utilisant un nid spécialement construit, nous avons pu séparer ces groupes fonctionnels. Nous avons donné aux fourmis de l'iode radio-actif (1251) mélangé à de la poudre de jaune d'œuf, de l'huile de soja ou une solution de miel à 50 % pendant 10 minutes. Le nombre de fourmis par nid et la quantité de nourriture marquée, consommée par fourmi, ont ensuite été mesurés. Lorsqu'elles ont reçu du miel ou de l'huile de soja, les colonies répondent en augmentant le nombre de fourrageuses et de «stockeuses de réserves» actives. Avec les deux sortes de nourriture, les fourrageuses consomment de grandes quantités de liquide; elles en transmettent des quantités plus petites aux «stockeuses de réserves» et aux nourrices. Lorsqu'on donne du miel «à 50 %» aux fourmis, moins de 0,2 % du miel recueilli par les fourrageuses parvient à la colonie; seulement 5 % des larves sont nourries après 10 minutes. Lorsqu'on donne de l'huile de soja, 2 % de l'huile recueillie parvient aux larves: à peu près 35 % des larves sont nourries après 10 minutes. Lorsqu'on donne de la poudre de jaune d'œuf, le nombre de fourrageuses est bas, mais celles-ci viennent plusieurs fois; elles laissent la nourriture à la périphérie du nid ou la transmettent aux «stockeuses de réserves». Les «stockeuses de réserves» transmettent rapidement la nourriture aux nourrices de sorte que, par rapport à l'huile et au miel, la quantité de nourriture consommëe par fourmi est la plus élevée parmi les nourrices. A peu près 80 % du couvain est nourri avec de la poudre de jaune d'œuf durant la période de 10 minutes, ce qui représente 6 % du jaune d'œuf recueilli par les fourrageuses. De cette étude, il apparaît que les ouvrières peuvent distinguer différents types de nutriments et, en conséquence, adapter leur comportement.
    Notes: Summary The imported fire ant,Solenopsis invicta Buren has three main functional worker groups: foragers, reserves, and nurses. By using a specially designed nest we were able to separate these functional groups by location. The ants were presented with 125 Iodine mixed with egg yolk powder, soybean oil, or 50 % honey solution for 10 minutes. The number of ants per nest location and the quantity of radiolabelled food consumed per ant were then measured. When presented with honey or soybean oil, colonies responded by increasing the number of foragers and active reserves. With both foods the foragers took in large quantities of liquid, passing on smaller amounts to the reserves and the nurses. When ants were presented with 50 % honey, less than 0.2 % of the honey collected by the foragers reached the brood. Only 5 % of the larvæ were fed after 10 minutes. When soybean oil was presented, 2 % of the oil collected reached the larvæ and approximately 35 % of the larvæ had been fed after 10 minutes. When the ants were presented with egg yolk powder, the number of foragers was low but they made repeated trips, leaving food on the nest periphery or passing it on to the reserves. Reserves relayed food rapidly to the nurses so that, in contrast to oil and honey, the quantity of food consumed per ant was greatest among the nurses and lower among the reserves and the foragers. Approximately 80 % of the brood were fed egg yolk powder within the 10 minutes period receiving 6 % of the egg yolk collected by the foragers. From this study it appears that workers can discriminate between nutrient types and adjust their behaviour accordingly.
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  • 7
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary During 45 months we have followed daily manyAnomma nigricans Ill. colonies in the Lamto area and we noticed that one society can divide and produce several times a new colony at short notice. For example the colonies ES and YT have respectively founded 3 and 2 new societies in 134 and 65 days. Other societies remained undivided for long periods. Two to four emigrations occuring at short intervals are observed between the statary phases necessary to the breeding of the sexual brood. A comparison between the different scissions and the time required for breeding mâles indicates that colonies can proceed to a secund cycle of foundation even before the end of the first one. Dans deux colonies, les fréquences de scissions paraissent exceptionnelles. Sur 46 autres colonies régulièrement suivies, nous n'avons, en effet, observé que 14 scissions. On peut s'interroger sur la cause d'une telle disparité? L'âge des reines serait-il en jeu? Il est bien difficile de répondre pour l'instant, la longévité et, en même temps, la grande mobilité des colonies d'Anomma rendant cette étude particulièrement difficile.
    Notes: Resume Nous avons suivi quotidiennement et pendant 45 mois de nombreuses colonies d'Animma nigricans Ill., dans la région de Lamto, en Côte d'Ivoire. Ceci nous a permis de constater qu'une même fourmilière pouvait se scinder et donner naissance à une nouvelle colonie plusieurs fois de suite en peu de temps. Nous citons le cas de deux colonies, ES et YT, qui ont produit respectivement 3 et 2 sociétés nouvelles en 134 et 65 jours. Par contre d'autres sociétés restent sans se reproduire pendant des périodes très longues. Entre les temps d'immobilisation des colonies, nécessaires à l'élevage du couvain sexué, on a observé de 2 à 4 déménagements très rapprochés. L'étude de la chronologie des scissions, comparée au temps nécessaire pour le développement du couvain mâle, permet d'affirmer qu'un processus de scission peut succéder à un autre avant même que le premier ne soit complètement achevé.
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  • 8
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    Insectes sociaux 26 (1979), S. 85-91 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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  • 9
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Des groupes expérimentaux, entièrement constitués de pseudergates deCoptotermes formosanus Shiraki, se sont différenciés librement au laboratoire pendant 4, 8 ou 12 semaines. Les pourcentages moyens de pseudergates qui se sont différenciés en soldats ou en soldats blancs ont été de 3,8 pour cent au bout de 4 semaines, 14,2 pour cent au bout de 8 semaines et 21,9 pour cent au bout de 12 semaines. La différenciation en soldat a été influencée par la taille initiale du groupe et le lieu d'origine de la colonie. Des groupes composés initialement de 100 pseudergates ont produit significativement une proportion plus faible de soldats que des groupes de 300, 500 ou 1000. Des colonies qui venaient d'être récoltées dans la nature ont fourni des taux significativement plus élevés de soldats qu'une colonie qui était gardée au laboratoire depuis 8 ans. Le nombre de soldats obtenu était en corrélation hautement positive avec le nombre total d'individus au bout de 4, 8 et 12 semaines. Ceci indique qu'il existe un mécanisme physiologique précis dans la régulation des proportions de soldats dans les colonies. Nous avons aussi constitué des groupes expérimentaux qui comprenaient des proportions «normales» (24%), «en dessous de la normale» et «au dessus de la normale» de soldats par rapport aux pseudergates. Lorsque la proportion de soldats était «en dessous de la normale», il y a eu inhibition de la production de présoldats de sorte que le développement en présoldats a progressivement diminué à mesure que la proportion de soldats par rapport aux pseudergates approchait de la «normale».Coptotermes formosanus Shiraki peut tolérer et maintenir une proportion remarquablement élevée de soldats (environ 38%), ce qui est bien au dessus de la proportion considérée comme «normale». Un grand nombre (mais pas tous) des soldats en surnombre ont été probablement éliminés par cannibalisme. Des groupes suchargés en soldats ont succombé à la contamination microbienne après que les soldats en surnombre fussent morts de faim. Je conclus de ces résultats que les colonies deCoptotermes formosanus gardent des soldats en proportion constante.
    Notes: Summary Experimental groups of 100 percent pseudergates ofCoptotermes formosanus Shiraki were set up in the laboratory and allowed to differentiate for either 4, 8 or 12 weeks. The average percentage of pseudergates differentiating into presoldiers and soldiers at these time intervals was 3.8, 14.2, and 21.9 percent, respectively. Differentiation to the soldier caste was affected both by initial group size and colony origin. Groups initially composed of 100 pseudergates produced a significantly smaller proportion of soldiers than did groups of 300, 500, or 1000. Recently collected field colonies produced soldiers at significantly higher rates than one which had been maintained in the laboratory for 8 years. The number of soldiers produced was highly correlated with the total number of all individuals at 4, 8, and 12 weeks, which indicates a precise physiological mechanism for regulating soldier proportions. Experimental groups were also set up with “normal” (24 percent), “below normal”, and “above normal” initial proportions of soldiers with pseudergates. ‘When soldiers were present in “below normal” proportions they inhibited the presoldier production, approached the norm. This species can tolerate and will maintain an exceptionally high proportion of soldiers (ca. 38 percent) which is far above the assumed “normal” proportion. Many, but not all, of the excess soldiers were probably eliminated by cannibalism. Groups severely overloaded with soldiers succumbed to microbial contamination after the excess soldiers starved to death. From these results I conclude that colonies ofC. formosanus do maintain numerically constant proportions of soldiers within broad limits. Thus, colonies might be controlled by chemically inducing the production of superfluous soldiers. Successful control would require the proportion of soldiers be so great that the pseudergates could not effectively reduce the numbers of soldiers by cannibalizing the excess individuals before their death by starvation resulted in microbial contamination of the entire colony.
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  • 10
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    Insectes sociaux 26 (1979), S. 147-153 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Les travaux précédents ont montré que les ouvrières deVespa orientalis sont capables de bâtir un rayon en l'absence de la reine (Ishay, 1973, 1975, 1976). Le présent travail examine d'une manière plus approfondie la construction du rayon par des ouvrières sans reine en groupes de taille différente (2, 12–17, 44–50 ouvrières). Les résultats ont montré que l'augmentation de la taille du groupe avait un effet défavorable sur le nombre de cellules du rayon ainsi que sur la structure de la construction. Les capacités de construction varient selon les individus: quelques-uns seulement construisent correctement, quelques autres incorrectement, et la grande majorité ne construit pas du tout. La durée du séjour des ouvrières à l'intérieur d'un groupe de construction est importante: les ouvrières qui ont été isolées après avoir séjourné à l'intérieur d'un groupe montrent une diminution de la tendance à bâtir; mais, parmi celles qui sont capables de construire, un plus grand nombre construit correctement.
    Notes: Summary In previous papers (Ishay, 1973; 1975; 1976) it was reported thatVespa orientalis workers are capable of building a comb in the absence of a queen. The present paper investigates further the comb building behaviour of queenless workers, arranged in groups of various sizes (2, 12–17, 44–50 workers), and of single isolated workers. Increasing group size was found to have an adverse effect on the amount and nature of the comb construction. The building abilities of various workers varied considerably. When isolated singly, only few workers built correctly, some built incorrectly and many failed to build altogether. Workers isolated immediately after emergence showed a greater tendency to build than workers isolated 3 or 4 days after emergence.
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  • 11
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    Insectes sociaux 26 (1979), S. 19-37 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume L'observation des jeunes sociétés de FourmisTapinoma erraticum (Dolichoderinae) a permis de classer les individus en fonction de leur activité dans l'approvisionnement du nid, celui-ci est effectué par des ouvrières spécialisées: les pourvoyeuses. On reconnaît 3 catégories d'ouvrières:les pourvoyeusss permanentes; elles sont pourvoyeuses dans plus de 80 % des observations et ne sont jamais nourrices, lespourvoyeuses intermittentes (de 20 % à 80 %) qui peuvent être simultanément pourvoyeuses et nourrices de larves, enfin les nourrices strictes (moins de 20 % des observations) qui s'occupent presque exclusivement du couvain. Le comportement est en relation avec l'âge: les ouvrières sont d'abord nourrices, ensuite pourvoyeuses intermédiaires et enfin pourvoyeuses permanentes. Les fourmis âgées de moins d'un mois sont en grande majorité nourrices (65 %), quelques-unes sont pourvoyeuses intermittentes (35 %). Parmi les ouvrières âgées de plus d'un mois 60% sont pourvoyeuses intermittentes, 30% pouroyeuses permanentes et 10 % restent nourrices. Les jeunes ouvrières deviennent en quelques jours de bonnes nourrices et soignent activement les larves alors qu'elles sont très mauvaises donneuses envers les autres ouvrières. A partir d'un mois, la majeure partie des ouvrières entre dans un pool d'individus disponibles selon les besoins de la colonie, ils sont pourvoyeurs mais peuvent aussi nourrir les larves ou la reine. La plus grande partie de l'approvisionnement est assurée par les pourvoyeuses permanentes qui sont de vieilles ouvrières et peuvent présenter une préférence alimentaire marquée vers des aliments de type sucré ou protéique L'évolution individuelle est très variable, elle peut être influencée par la pression sociale: s'il manque des pourvoyeuses âgées et c'est le cas lorsque le nombre de jeunes ouvrières est supérieur à celui des ouvrières âgées, les jeunes de moins d'un mois peuvent devenir momentanément pourvoyeuses.
    Notes: Summary The study of alimentary behaviour in newly founded societies of antsTapinoma erraticum (Dolichoderinae) with marks on the gaster enabled us to classify the individuals in terms of foraging and brood care. There are 3 different groups: permanent foragers (foragers in more than 80% observations), intermittent foragers (between 20 to 80%) and nurses (less than 20%). The behaviour of ants changes with age: young ants are nurses at first, them they are intermittent foragers, and permanent foragers at last. Ants less than one month old are calledyoung (under laboratory conditions): 65% of them are nurses, some are intermitent foragers (35%). Ants more than one month old are calledold: 60% are intermittent foragers, 30% permanent foragers and 10% only nurses. Young workers become nurses very quickly (in a few days) but they are not active donors to other workers. After one month most of them become members of a pool of unemployed ants able to forage and give food to the queen or larvae. Most of the foraging is done by permanent foragers, older workers. Individual development is very variable, according to social pressure, if there are not enough old foragers, young ants become foragers. This phenomenon can be reversible.
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  • 12
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    Insectes sociaux 26 (1979), S. 61-68 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung 12 Proben vonFormicoxenus hirticornis (Emery) wurden im August 1977 im Yellowstone Park, Wyoming, aus 4 Nestern vonFormica obscuripes entnommen. Die entflügelten Weibchen und Intermorphen sowie einige Arbeiterinnen wurden seziert. Alle 16 Weibchen und 13 der Intermorphen waren begattet, doch legten nur 10 Weibchen und 4 Intermorphe Eier. des Volk scheint normalerweise nur ein voll fertiles und daneben einige zusätzliche, begattete, aber sterile Weibchen oder Intermorphe zu enthalten. Diese Ergebnisse sind unseren Beobachtungen an der europäischen GastameiseFormicoxenus nitidulus (Nyl.) sehr ähnlich. Wir schließen daraus, daßF. hirticornis (und vielleicht auch der nahe verwandteF. diversipilosus) wieF. nitidulus undLeptothorax gredleri Mayr funktionell monogyn ist, das heißt, daß überzählige begattete Weibchen und Intermorphe in weiselrichtigen Sozietäten zwar akzeptiert, aber durch einen bisher unbekannten Mechanismus steril gehalten werden. Leptothorax hirticornis Emery undL. diversipilosus M.R. Smith gehören meines Erachtens in die GattungFormicoxenus, da sie eine Anzahl einzigartiger Merkmale mitF. nitidulus gemeinsam haben: Die Männchen aller drei Arten sind flügellos und arbeiterinähnlich, alle drei leben als Gastameisen in Hügelnestern vonFormica-Arten, und sie haben einen merkwürdigen Polymorphismus mit entflügelten und intermorphen königinnen neben normalen Arbeiterinnen.
    Notes: Summary 12 samples ofFormicoxenus hirticornis (Emery) were collected from 4Formica obscuripes nests in the Yellowstone Park, Wyoming, in August, 1977. The dealate females and intermorphs, and some workers were dissected. All 16 females and 13 of the 16 intermorphs were inseminated, but only 10 females and 4 intermorphs were egg-laying. It seems that each colony normally contains only one fully fertile specimen, and a few additional, inseminated but sterile females or intermorphs. These results are very similar to our observations on the European guest-antFormicoxenus nitidulus (Nyl.). We conclude thatF. hirticornis (and maybe the closely relatedF. diversipilosus, too) is functionally monogynous likeF. nitidulus andLeptothorax gredleri Mayr, which means that supernumerary inseminated females and intermorphs are accepted in queenright colonies, but they are kept sterile by a mechanism which is not yet known. Leptothorax hirticonis Emery andL. diversipilosus M.R. Smith in my opinion belong to the genusFormicoxenus, since they have, together withF. nitidulus, a number of unique, common characters: The males of all three species are wingless and workerlike, they all live as guest ants in the mound nests ofFormica species, and they have a peculiar female polymorphism with both dealate and intermorphic queens besides normal workers.
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  • 13
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary Females and immatureElasmucha grisea form an association in which the mother protects its offsprings at longest to the fourth instar. The cohesion of the protective association is assured by a trail substance which is released by the larvae when moving over the surface. Both larvae (with exception of the first instar) and mother can follow such trails. A definitively perceptible trail is first produced after the passage of several larvae (with instar 3 five larvae). A trail laid by twenty larvae (instar 3 and 4) can still be followed by larvae after half an hour. The defensive secretion ofElasmucha grisea larvae and adults has an additional alarm function. It releases attack reactions in the protecting female, i.e. a directed movement toward the source of odor and wing fanning. With exception of the first instar the larvae react to the alarm secretion with a well organized group flight. Young adults can also react to the alarm substance by falling. The larval defensive secretion is a complex mixture of substances. The 2-hexenal contained in the secretion causes a larval unrest but no typical flight reaction.
    Notes: Zusammenfassung Weibchen und Jungtiere vonElasmucha grisea bilden eine Brutpflegegemeinschaft, in der das Muttertier seine Nachkommenschaft maximal bis zum vierten Larvenstadium beschützt. Der Zusammenhalt der Schutzgemeinschaft wird durch einen Spurstoff gewährleistet, den die Jungtiere beim Laufen auf die Unterlage abgeben. Sowohl Larven (mit Ausnahme des L 1 Stadiums) als auch die Mutterwanze können dieser Spur folgen. Eine gesichert wahrnehmbare Spur entsteht erst, wenn mehrer Larven hintereinander laufen (bei L 3 fünf Larven). Einer von 20 Larven (L 3+L 4) gelegten Spur konnten die Jungtiere noch nach einer halben Stunde sicherbar folgen. Das bei Bedrohung freiwerdende Wehrsekret von adulten und larvalen Wanzen hat zusätzlich Alarmfunktion. Es veranlaßt die brutpflegende Mutterwanze zum Angriff, d.h. zu gerichtetem Anlauf der Duftquelle und zu Flügelschwirren. Mit Ausnahme des L 1 Stadiums reagieren Jungwanzen auf das Wehrsekret mit geordneter Gruppenflucht. Junge Adultwanzen können sich bei Alarmsekretgabe fallen lassen. Das larvale Wehrsekret ist ein komplex zusammengesetztes Substanzgemisch. Das darin enthaltene 2-Hexenal löst bei Larven Unruhe aber keine typischen Fluchtreaktionen aus.
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    Insectes sociaux 26 (1979), S. 155-164 
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Resume Le fait d'enlever la reine entraîne le développement des ovaires des ouvrières chez le Frelon orientalVespa orientalis L., surtout dans les cinq jours suivants. Le refroidissement des ouvrières ou la fourniture à celles-ci d'un régime sans protéines inhibent leur développement ovarien, mais, dans les deux cas, l'inhibition disparait dès que ces conditions artificielles sont levées. Dans les groupes d'ouvrières, le developpement des ovaires apparait seulement chez les ouvrières du haut de la hiérarchie. Cependant, on l'observe chez toutes les ouvrières qui ont été isolées après qu'elles aient vécu en groupe. Par ailleurs, l'inhibition du développement ovarien se produit chez 50% environ des ouvrières qui ont été isolées depuis leur éclosion imaginale, ce qui suggère que les contacts sociaux stimulent de développement ovarien des ouvrières orphelines. Le développement ovarien a été aussi observé chez les ouvrières qu'on empêchait de construire: nous discutons la relation entre l'activité de construction et le développement ovarien.
    Notes: Summary Removal of the queen induced ovarial development in workers of the Oriental hornet,Vespa orientalis L. This occurred in workers kept in groups and mainly during the first five days after removal of the queen. Cooling of the workers or their subjection to a protein-free diet inhibited their ovarial development, but in either case, the inhibition disappeared once normal conditions were restored. For workers living in a group, ovarial development occurred only in workers of high hierarchal rank. However, the ovaries developed in all workers which were isolated singlyafter having lived in a group. On the other hand, inhibition of ovarial development occurred in about 50% of workers isolated singly from the moment of emergence, which suggests that social contact acts as a releasing stimulus for ovarial development in queenless hornet workers. Development of the ovaries was observed also in worker groups prevented from building, and the connection between building and ovarial development is discussed.
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    Insectes sociaux 26 (1979), S. 216-222 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Doronomyrmex pocahontas n.sp. wird beschrieben. Die neue Ameise sieht der europäischenDoronomyrmex pacis Kutter sehr ähnlich. Königinnen und geflügelte Jungweibchen wurden in 3 Völkern einerLeptothorax muscorum (Nyl.) nahestehenden Wirtsart gefunden. Locus typicus ist der Maligne Canyon bei Jasper, Alberta, Kanada. Die neue Art ist offenbar wieD. pacis ein arbeiterinloser, permanenter Sozialparasit. Männchen konnten nicht mit Sicherheit identifiziert und von den Männchen der Wirtsart unterschieden werden. Auch ist unbekannt, obD. pocahontas die Wirtsköniginnen tötet oder wieD. pacis mit ihnen zusammenlebt.
    Notes: Summary Doronomyrmex pocahontas n. sp. is described. The new ant closely resembles the European species,Doronomyrmex pacis Kutter. Queens and alate young females were found in 3 colonies of a host species which is or is closely related toLeptothorax muscorum (Nyl.). The type locality is Maligne Canyon, near Jasper, Alberta, Canada. The new species is an apparently workerless, permanent social parasite like its congener,D. pacis. No males could be identified or distinguished from host species males with certainty. WhetherD. pocahontas kills the host colony queens or lives alongside them (likeD. pacis) could not be decided.
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    Description / Table of Contents: Summary The cycle of activity and diet ofBrachyponera senaarensis were studied in the rainy season (june 77) in order to compare them with observations onducted in a Sudan Savannah of the north eastern part of the Ivory Coast near Ferkessedougou. As in dry season, the cycle of activity is, in june, bimodal but the daily fluctuations appear to be more important and some workers of this typically diurnal species even try to hunt in the first half of the night. Ants hunting on the soil surface are, at that period, in a ratio of one to three compared to those collecting in the dry season. In same way, the surfaces of the prospected areas are smaller in the ratio of one to three. Between 20° and 44°C soil surface temperature, the abundance of seeds seems to exert a major influence on the local distribution of the above ground activities. In the rainy season, in the absence of seeds,Brachyponera acts as a predator of termites and small spiders. Thus, the species seems to be particularly well adapted to that climatically contrasted region.
    Notes: Resume Le cycle d'activité de récolte et le régime alimentaire deBrachyponera senaarensis (Ponerinae) ont été étudiés en saison des pluies (juin 1977) dans une savane de type soudanien près de Ferkéssédougou (Nord-Est de la Côte d'Ivoire). Ce cycle d'activité, typiquement bimodal, se déroule essentiellement de jour. Les fluctuations journalières peuvent être notables, provoquant le déplacement dans la soirée d'une partie de l'activité diurne. En saison des pluies l'espèce est, au total, moins active en surface qu'en saison sèche. La disponibilité en graines semble être le facteur exerçant l'influence la plus grande sur le déroulement du cycle. En l'absence de graines, l'espèce est prédatrice, son action s'exerçant surtout aux dépens des Termites et Araignées de petite taille.
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    Insectes sociaux 26 (1979), S. 273-278 
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    Topics: Biology
    Description / Table of Contents: Resume Il y a deux théories différentes sur les mécanismes d'action de la substance royale de l'Abeille domestique (Apis mellifera) sur le développement ovarien des ouvrières. L'une de ces théories propose un mécanisme humoral direct, l'autre une modulation du système neuro-endocrinien par la chémoréception. Nous avons donné aux larves de Mélipones de l'acide 9-oxo-décène oïque, seul ou en association avec l'hormone juvénile, puis nous avons étudié l'effet éventuel de ces traitements sur la détermination des castes. Nous n'avons trouvé de modifications ni dans le pourcentage des reines par rapport aux ouvrières, ni dans la biométrie des caractères morphologiques. Nos résultats ne plaident donc pas en faveur d'un effet humoral de l'acide 9-oxo-décène oïque sur le déterminisme des castes chez les Mélipones. Ceci rend plus probable l'hypothèse d'un mécanisme neuro-endocrinien modulé par les organes des sens.
    Notes: Summary Two different theories exist concerning the way in which the honeybee “queen substance” affects the ovaries of worker honeybees. One theory involves a humoral mechanism, the other an indirect effect through the neuro-endocrine system after chemoperception. 9-Oxo-decenoic acid, one of the components of the “queen substance”, was administered to stingless bee larvae, alone or in combination with juvenile hormone. The effect of this treatment on caste determination was studied. Since no effect was found on the worker/queen ratio nor on morphometric characteristics, these experiments do not favour a humoral effect of 9-oxo-decenoic acid on stingless bee caste determination. This makes a sensory mechanism in the honeybee itself more probable.
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    Insectes sociaux 26 (1979), S. 322-342 
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    Topics: Biology
    Description / Table of Contents: Resume Les mécanismes d'acroissement du nid deNasutitermes costalis, ont été analysés par l'observation directe et par la photographie d'une colonie prospère, élevée au laboratoire pendant plus de 45 mois. Nous avons enregistré 52 périodes d'accroissement, chacune entraînant une augmentation de 10% du volume du nid. On peut diviser le processus d'accroissement du nid en 3 phases: la phase initiale, la phase de construction, la phase finale. La phase finale aboutit à une surface dont la forme traduit la convergence des premiers efforts de construction pendant la phase initiale d'accroissement. La construction est basée presque entièrement sur des répétitions multiples d'un petit nombre d'éléments architecturaux simples, essentiellement la division, d'un mur en deux embranchements et la réunion de murs voisins au moyen d'un pont. Tout cela se passe sur une “surface active” lisse qui demeure ainsi tout le temps de chaque période d'accroissement. Les intéressantes similitudes entre certains traits architecturaux de l'accroissement du nid deN. costalis, et certaines structures construites «de novo» par des groupes de termites avec une reine et appartenant à trois sous-familles de Termitidae suggèrent que le mode d'accroissement du nid deN. costalis est relativement primitif.
    Notes: Summary The nest expansion behavior ofNasutitermes costalis, a common Neotropical arboreal termite, was analyzed by means of direct and photographic observation of a thriving laboratory colony over a 45-month period. 52 expansion episodes were recorded, each resulting in the addition of as much as 10% to the nest volume. The expansion process can be divided into 3 phases Initiation, Building, and Termination. Termination results in a nest surface whose shape focuses initial building efforts during the Initiation of subsequent expansion. Building consists almost entirely of multiple repetitions of a few simple architectural elements — primarily the branching of one wall into two and the joining of neighboring walls via a bridge — all occurring on a smooth “active surface” which persist throughout each expansion episode. Interesting similarities between certainN. costalis nest expansion architectural features and structures builtde novo by queened termite groups from 3 subfamilies of the Termitidae suggest that this is a relatively primitive mode of nest expansion.
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    Insectes sociaux 26 (1979), S. 364-372 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die grössten Ameisenkolonien in der nordamerikanischen Sonora Wüste bildet die mexikanische BlattschneiderameiseAtta mexicana, deren Futtersammelaktivitäten erstmalig beschrieben werden. Zum Futtersammeln benutzen diese Ameisen ein System aus Tunneln und Strassen, das vom Nest zu der Vegetation führt. Die Hauptbeobachtungskolonie wurde während mehrerer Jahre in den Monaten Dezember, Januar, März und Juli/August insgesamt 24 Tage lang kontrolliert. Sie sammelte während dieser Zeit Pflanzenmaterial auf einer Grundfläche von etwa 8000 m2. Die Ameisen schnitten bevorzugt zwei annuale Pflanzenarten, nahmen aber, wen diese fehlten, auch mehrere Arten von perennierenden Pflanzen an. Zusätzlich zu frischen wurden auch trockene Pflazenteile eingetragen. Das Schneideverhalten der Ameisen war variabel und hing von Grösse und Form der Pflanzen ab. Die Ameisen sammelten in Winter und Frühling tagsüber und gingen im Sommer weitgehend zu nächtlicher Sammelaktivität über.
    Notes: Summary The largest ant colonies in the North American desert are produced by the Mexican leafcutting ant,Atta mexicana (F. Smith), in northern Sonora. The foraging behavior ofA. mexicana is described for the first time. The ants use a system of tunnels and trails extending outward from the nest to reach target vegetation. Over the combined study periods from 1974 to 19777, one colony collected material from a total surface area of about 8,000 m2. The ants selectively attacked two species of winter annual plants and repeatedly utilized four perennials, twoCercidium spp.,Sapium biloculare (S. Wats.), and Larrea tridentata Coville when the annuals were absent. In addition to fresh vegetation, they also collected dry material. The leafcutting behavior of the ants is variable, depending on the size and form of the plant material utilized. The ants foraged during the daytime in winter and spring but became largely nocturnal in summer.
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    Insectes sociaux 26 (1979), S. 373-381 
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    Topics: Biology
    Description / Table of Contents: Resume Nous décrivons le «timing» de l'élevage des reines et de l'essaimage après avoir enlevé la reine dans des colonies d'abeilles «africanisées». De nouvelles reines ont été élevées à partir de larves de moins de 3 jours; beaucoup de celles-ci et beucoup d'œufs ont été déplacés par les ouvrières dans des cellules de reines nouvellement construites. Le taux de mortalité les ouvrières dans des cellules de reines nouvellement ouvrières a été élevé, en moyenne de 50%, après l'orphelinage expérimental. A l'éclosion des nouvelles reines, 2/3 des colonies ont essaimé. Ces processus de remplacement de la reine et d'essaimage après la perte de celle-ci diffèrent de ceux des essaimages de reproduction par le manque de préparation avant la perte de la reine, un intervalle de temps sans rene plus long, et une absence de l'essaimage. Par ailleurs il n'y a pas de corrélation entre le nombre d'essaims et la surface occupée par le couvain operculé ou le nombre de cellules royales.
    Notes: Summary The timing of queen rearing and swarming are described after queens were removed from colonies of Africanized bees. New queens were reared from newly hatched to three day old worker larvae, many of which were moved in the egg or newly eclosed larval stages by workers into newly constructed queen cells. Mortality of worker eggs and larvae following dequeening was high, averaging 50%. When new queens emerged, swarms issued from two-thirds of the colonies. This process of queen replacement and queen-loss swarming differs from that of reproductive swarming in the lack of preparation before queen loss, longer queenless interval, lack of correlation between number of swarms and sealed brood area or number of queen cells, and lack of Congestion in colonies when swarms issued.
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    Pure and applied geophysics 119 (1981), S. 966-977 
    ISSN: 1420-9136
    Keywords: Streamer interactions
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    Topics: Geosciences , Physics
    Notes: Abstract Investigation was carried out to study the interaction of positive streamers with charged and uncharged drops in a vertical electric field configuration. Results obtained for vertical and horizontal positions of the photographic films show that streamer interactions with neutral and negative drops are similar and further confirmed earlier results byPhelps (1972). It showed that indirect streamer interaction with droplets is effected by branches being sent to the drops from the main channel. The visibility of the branches on the Lichtenberg figures and the degree of interaction of streamers with drops depend on the drop size, its initial charge and shape, and/or the separation of the drops from the main channel. Suppression of streamer propagation among the positively charged drops was observed.
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    Pure and applied geophysics 119 (1981), S. 978-989 
    ISSN: 1420-9136
    Keywords: Ozone maxima ; Dry deposition ; Local cross-valley wind system
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    Notes: Abstract The diurnal cycle of ozone at the surface and within the PBL is examined. It is concluded that the intrusion of air masses from ozone-rich layers in the lower troposphere results in late evening ozone maxima observed at ground stations on mountain slopes as well as within distinct layers of the PBL above the valley bottom. The ozone-rich layers are assumed to exist due to meso- or large-scale horizontal transport of smog air masses and a local cross-valley wind system is shown to be responsible for the occurrence of the intrusion processes.
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    Pure and applied geophysics 119 (1981), S. 934-965 
    ISSN: 1420-9136
    Keywords: Condensation ; effect of entrainment on ; Cloud drop formation ; effect of entrainment on
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    Notes: Abstract It has been speculated for many years that the development of the droplet spectra in cloud is probably influenced by mixing processes. Various theoretical attempts to broaden the droplet spectra by mixing parcels with different velocity histories has shown that that particular effect is small. Similarly, very simpleuniform entrainment procedures did not lead to cloud drop size spectra which were broad enough, although by producing cloud drop size distributions with a double mode these models did substantially improve the drop size spectra of earlier adiabatic models which only exhibited a single mode. Recently a model based on entraining entities representing moving parcels of cloud air within the cloud was detailed byTelford andChai (1980). This study showed that the mixing in of dry air at cumulus turrets could lead to vertical cycling of diluted parcels, and that this cycling, with continual entrainment across the parcel boundaries, will produce much larger drops, as well as smaller drops of all sizes, in the droplet spectra. The ‘entity entrainment’ concept studied there appears to apply to the observations of stratus cloud discussed in this paper. This paper presents data taken in marine stratus off the California coast which give a particularly clear example of how such droplet spectra modification occurs in practice. Both large drops, and the spread of the spectra to smaller sizes, occur in relation to other variables in such a way as to be consistent with an entity entrainment explanation, with no other obvious possibility. In a marine stratus cloud just over 200 m thick and many tens of miles in extent we find clear evidence that dry air is mixing in at cloud tops. Strong vertical motion is to be found in the cloud, large sized drops are found in cloud parcels where the mixing gives lower droplet concentrations, and there is evidence that newly formed cloud parcels are warmer and contain many more smaller droplets. The observations show that immediately following entrainment of dry air drop diameters are not reduced appreciably, but, in the same parcels, drop concentrations have been reduced by a factor of ten or more. Further down in the cloud big drops, able to start growth by coalescence, are found associated with low total droplet concentrations. Overall, it seems likely from the consideration of these observations that the formation of the large drops which lead to precipitation processes in clouds depends critically on the mixing in of dry air at cloud tops, and very little on the size of the small drops resulting from the condensation nucleus counts. As a conclusion it appears reasonable to state that if entrainment occurs at cloud tops, then big drops will be formed!
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    Pure and applied geophysics 119 (1981), S. 1024-1036 
    ISSN: 1420-9136
    Keywords: Electromagnetic scattering ; VLF electromagnetic prospection
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    Topics: Geosciences , Physics
    Notes: Abstract FollowingDmitriev (1960) a rigorous theoretical solution for the problem of scattering by a perfectly conducting inclined half-plane buried in a uniform conductive half-space has been obtained for plane wave excitation. The resultant integral equation for the Laplace transform of scattering current in the half-plane is solved numerically by the method of successive approximation. The scattered fields at the surface of the half-space are found by integrating the half-space Green's function over the transform of the scattering current. The effects of depth of burial and inclination, of the half-plane on the scattered fields are studied in detail. An increase in the depth of burial leads to attenuation of the fields. Inclination introduces asymmetry in the field profiles beside affecting its magnitude. Depth of exploration is greater for quadrature component. An interpretation scheme based on a phasor diagram is presented for the VLF-EM method of exploration for rich vein deposits in a conductive terrain.
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    Pure and applied geophysics 119 (1981), S. 1077-1092 
    ISSN: 1420-9136
    Keywords: Seismic hazard estimation ; Bohemia
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    Topics: Geosciences , Physics
    Notes: Abstract The contribution reviews basic concepts of earthquake hazard assessment for sites of nuclear power plants. Taking into account the delineation of earthquake source regions, intensity-frequency relations, upper intensity thresholdsI max and intensity attenuation curves, we determine the seismic hazard for a site in south Bohemia and calculated the quantities defining the seismic hazard, i.e. return period in years, probability of exceedance for different intensities and different periods of interest. The adopted procedure has some limitations due to the poor definition of seismogenic zones (boundaries,N(I),I max) and lack of strong motion observations in Central Europe.
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    Pure and applied geophysics 119 (1981), S. 1125-1133 
    ISSN: 1420-9136
    Keywords: Seismicity and crustal structure
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    Notes: Abstract Focal solutions of four strong earthquakes and P signals of twenty-four smaller shocks of the active Mur-Mürz Valley, the Semmering Pass and the Vienna Basin. An ‘equivalent slip rate’ of 0.03 This feature agrees with the model of a subsiding Pannonian Basin. An ‘equivalent slip rate’ of 0.03 cm/year is roughly estimated from earthquake data 1903–1978. This rate does not include the creep rate, but it gives an idea of the magnitude of speed of geological processes in this area. Refraction seismic data from the Alpine Longitudinal Profile 75 shows a low velocity zone in the upper crust of the seismic active East Alpine area but not in the aseismic part of the Pannonian Basin. The eastern margin of the Eastern Alps and the Carpathians limits the Pannonian Basin, which has a special and interesting geological history. Many authors (Szadezky-Kardoss, 1966;Stegena, Ceszy andHorvàth, 1975) presented models of the genesis of the Pannonian Basin. They apply the concept of the ‘mantle diapirs’ to explain the following facts: subsiding of the Pannonian Plate in comparison to the Alps, high terrestrial heat flow within the Pannonian Plate, decrease of the Moho depth from 40 km below the Eastern border of the Alps to 27 km below the Pannonian Basin. They claim that the Alpine-Carpathian interarc and basin represent the final stage of an orogenetic system where ‘subcrustal erosion’ leads to a thinning of the crust. Consequently the surface subsides and is covered by young sediments. They proved that this subsidence and sedimentation is more or less in isostatic equilibrium. The aim of this paper is to provide new arguments using focal solutions and refraction seismic investigations.
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    Keywords: Caucasus ; Three-dimensional seismic modelling
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    Notes: Abstract This paper deals with a procedure of a joint analysis of seismic data from earthquakes and those obtained by DSS. The DSS data are used as a first approximation to construct a two-dimensional model of the medium made up of individual blocks. These models serve as a basis when constructing specific three-dimensional travel-time curves. These travel-time curves are further used for the calculation of hypocenter parameters in a laterally inhomogeneous block medium. The hypocenter field and the travel times obtained are input data for the computation of three-dimensional fields of velocities in earthquake focal zones. Results of applying the proposed procedure to the Caucasus region are presented.
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    ISSN: 1420-9136
    Keywords: Cloud condensation nuclei ; Nuclear fission products ; -concentration of in air
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    Notes: Abstract The concentrations of airborne fission products were observed to be air mass dependent during a cruise of the USNSHayes from Norfolk, Va to Athens, Greece in May–June 1977. Minimum concentrations of fission products, radon, and CCN (cloud condensation nuclei) were measured in maritime air which had previously transited northern North America. Higher fission products, radon, and CCN concentrations were measured in recent, continental air traceable to mid North America or central Europe. These data are consistent with either entrainment by strong winds of previously precipitated fission products (the ‘continental effect’) or greater transfer of fission products from the stratosphere to low levels by tropospheric folding.
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    Pure and applied geophysics 117 (1979), S. 865-873 
    ISSN: 1420-9136
    Keywords: Energetics ; Monsoon
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    Topics: Geosciences , Physics
    Notes: Abstract The various forms of energy and energy conversions have been computed over a part of the Indian region during an active monsoon period, using the quasigeostrophic baroclinic model. The energetics of the monsoon depression have been discussed on the basis of these results.
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    Pure and applied geophysics 117 (1979), S. 935-942 
    ISSN: 1420-9136
    Keywords: Estuary ; Hydrographic conditions
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    Topics: Geosciences , Physics
    Notes: Abstract In order to understand the various processes responsible for siltation in the entrance channel and in the sand bar area near the old Mangalore port, variations in temperature, salinity, suspended sediment load, currents and extinction coefficient in the Netravathi-Gurpur Estuary and in the sea near the sand bar were studied in relation to tides during monsoon, post-monsoon and pre-monsoon seasons. The hydrographic characteristics in the estuary showed marked seasonal changes and were influenced by tides to a considerable extent. In the sea, seasonal variations of these parameters were less marked, and the effect of tides was not significant. Salinity and temperature values in the estuary and in the sea were maximum during the pre-monsoon season in general. The suspended sediment load values were always higher in the estuary than in the sea and they were found to be maximum in the monsoon season. Currents in the estuary were controlled by tides as well as by the river flow, particularly in the monsoon season, whereas currents in the sea mostly followed the general circulation pattern. Extinction coefficient values were higher in the monsoon season both in the estuary and in the sea due to increase in the particulate matter from inland drainage.
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    Pure and applied geophysics 117 (1979), S. 988-1000 
    ISSN: 1420-9136
    Keywords: Electric potential ; resistivity structure with scatter
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    Topics: Geosciences , Physics
    Notes: Abstract Solutions are derived for the potential distributions over one-layer and two-layer random conductivity earth models for the direct current resistivity method. Monopole and Wenner arrays are considered. It is shown that the random potential due to a spatially stationary Gaussian random conductivity is also Gaussian but not spatially stationary. The ensemble and sample statistics of the random kernel and apparent resistivity are examined. Representative curves of these functions are presented to show the effects of a random conductivity profile on them. It is shown that the effect of the random nature of the conductivity profile on an apparent resistivity sounding curve is greatest for small electrode spacings.
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    Pure and applied geophysics 117 (1979), S. 1045-1049 
    ISSN: 1420-9136
    Keywords: Seismology ; Surface waves
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    Topics: Geosciences , Physics
    Description / Table of Contents: Summary Alsop's method (1966) for the non-normal passage of surface waves through a vertical discontinuity is improved by using a new functional to be made stationary on the plane of discontinuity. The modified functional has the dimension of an energy flux and is characterized by the discontinuous surface wave displacements and stresses on the vertical discontinuity. Model calculations which were carried out for SV-waves and Love waves show that the new version of Alsop's method yields in all respects more consistent results than the old one.
    Notes: Zusammenfassung Die Methode von Alsop (1966) für den Durchgang von schräg einfallenden Oberflächenwellen durch eine vertikale Diskontinuität wird durch Verwendung eines neuen Funktionals, das auf der Diskontinuitätsfläche stationär sein soll, verbessert Das modifizierte Funktional hat die Dimension eines Energieflusses und wird durch diejenige Spannungs- und Verschiebungsdiskontinuität charakterisiert, die durch das Oberflächenwellenfeld auf der Diskontinuitätsfläche erzeugt wird. Modellrechnungen für SV-Wellen und Lovewellen zeigen, daß die neue Version von Alsoos Verfahren in jeder Hinsicht konsistentere Ergebnisse als die bisherige liefert.
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    Pure and applied geophysics 117 (1979), S. 1258-1270 
    ISSN: 1420-9136
    Keywords: Earthquake prediction ; Seismicity migration ; Tectonics of Turkey
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    Topics: Geosciences , Physics
    Notes: Abstract The North Anatolian fault is a well-defined tectonic feature extending for 1400 km across Northern Turkey. The space-time distribution of seismicity and faulting of this zone has been examined with a particular emphasis on the identification of possible seismic gaps. Results suggest several conclusions with respect to the temporal and spatial distribution of seismicity. First, the earthquake activity appears not to be stationary over time. Periods of high activity in 1850–1900 and 1940 to the present bracket a period of relatively low activity in 1910–39. Second, there appears to have been a two-directional migration of earthquake epicenters away from a central region located at about 39°E longitude. The migration to the west has a higher velocity (〉50 km/yr) than the migration to the east (≤10km/yr). The faulting associated with successive earthquakes generally abuts the previous rupture. Some existing gaps were filled by later earthquakes. At present there are two possible seismic gaps along the North Anatolian fault zone. One is at the western end of the fault, from about 29° to 30°E. Unless this is a region of ongoing aseismic creep, it could be the site of a magnitude 6 or greater earthquake. The other possible gap is at the eastern end, from about 42° to 43°E, to the west of the unexpected M=7.3 event of 24 November 1976.
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  • 34
    ISSN: 1420-9136
    Keywords: Earthquake prediction ; Seismicity and rainfall ; Tectonics California
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    Topics: Geosciences , Physics
    Notes: Abstract By comparing seasonal rainfall data from the past 90 years with the occurrence of large (M≥6) earthquakes along an arid stretch of the San Andreas fault system in southern California, certain correlations have been observed. Most large earthquakes are preceded by a pattern consisting of a few years of below normal precipitation (drought) terminated by one or more consecutive seasons of heavy (above normal) rainfall. While this drought-above normal rainfall cycle can be seen at times other than prior to major earthquakes, it precedes, to varying degrees, all of the twelve M≥6 events. This new precursor evidence, when combined with other premonitory signals, may offer a helpful diagnostic measure that could be useful in earthquake prediction in arid regions.
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  • 35
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    Pure and applied geophysics 119 (1981), S. 901-912 
    ISSN: 1420-9136
    Keywords: Monsoon depression ; Cyclogenesis ; Barotropic instability
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    Topics: Geosciences , Physics
    Notes: Abstract The role of barotropic processes in the development of a monsoon depression, formed on 5 July 1979 during MONEX observational period, is studied by considering it as a quasi-geostrophic divergent barotropic instability problem of zonal flow of 3 July 1979 at 700 mb level. Numerical solutions are obtained by initial value approach. The preferred wave has a wavelength of 2750 km, an e-folding time of 4.3 days, a period of 6.5 days and an eastward phase speed of 4.9 ms−1. Structure of preferred wave is found to be in good agreement with the observed horizontal structure of the depression at 700 mb. Poleward momentum transports are found to predominate over equatorward transports.
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    Pure and applied geophysics 119 (1981), S. 922-933 
    ISSN: 1420-9136
    Keywords: Extreme precipitation ; Tropical meteorology
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    Topics: Geosciences , Physics
    Notes: Abstract The greatest one-day rain amounts recorded at individual stations in the country during the last 41-year period from 1940 onwards were examined for all observatories as well as State rain-gauge stations in an attempt to bring out up-to-date information on the greatest recorded point rainfall for the duration of one day. Outstanding one-day point rainfall amounts recorded prior to 1940 were also examined and have been included in this note along with their date and year of occurrence by way of comparison. A generalized chart has been prepared based on the percentage ratios of the greatest one-day rainfall to the mean annual rainfall of about 300 observatory stations distributed uniformly over the entire country. On the basis of Depth-Area-Duration (DAD) analyses of the most severe rainstorms which occurred over different plain areas of the country, it has been found that the 2 July, 1941, rainstorm gave the highest areal rain depths in the country for different areas. Comparison with similar areal rain depths of the tropical USA has shown that rain depths of the July, 1941, rainstorm were higher for all areas excepting the areas of 500 sq. miles (1295 sq. km) and 1000 sq. miles (2590 sq. km).
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    Pure and applied geophysics 119 (1981), S. 990-997 
    ISSN: 1420-9136
    Keywords: Atmospheric trace gases ; Atmospheric chemistry ; Chemical composition of atmospheric boundary layer
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    Topics: Geosciences , Physics
    Notes: Abstract Weekly air samples were collected at Cape Kumakahi (0 km) and at nearby Mauna Loa Observatory (3.4 km) which is above the boundary layer. EC/GC and GC/FID techniques were used to measure CH3I, CHCl3, CO and CH4, which are largely natural in origin, and C2Cl4, CCl4, CH3, CCl3, CCl3F (F-11), CCl2F2 (F-12), CHClF2 (F-22) and C2F3Cl3 (F-113), which are due to anthropogenic activities. It was found that all these gases are significantly (α≤0.05) more abundant in the boundary layer than above it.
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    Pure and applied geophysics 119 (1981), S. 1003-1023 
    ISSN: 1420-9136
    Keywords: Geoelectric data ; Transmission Line analogy ; Filter theory ; stable stochastic inverse
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    Topics: Geosciences , Physics
    Notes: Abstract A simple numerical inversion scheme for estimatingn-layer model parameters from observed geoelectrical resistivity data can be used in either the space or wavenumber domain. The technique utilizes Madden's Transmission Line Analogy to compute the resistivity transforms and linear filter theory to accomplish the excursions between the space and wavenumber domains. The inversion is effected by an iterative refinement scheme employing the stochastic inverse which is approximate to the generalized inverse. No singular decomposition analysis is required and the scheme is stable under ill conditions. The inversion scheme not only gives the desired estimates; it exposes redundant parameters and irrelevant data and is easily programmed on a desk-top mini computer. Examples of inverse modeling with hypothetical and field data are discussed.
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  • 39
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    Notes: Abstract P- and S-wave velocity distributions obtained from DSS measurement have been used as a constraint in the inversion of surface-wave dispersion data. The combined interpretation was made as an attempt to enhance the resulting velocity models and to test the possibility to draw conclusions about the density distribution. The result indicates a potential value of a combined interpretation but it is obvious that very accurate velocity distributions are needed. The achieved density distribution is in good agreement with reported densities derived from gravimetric studies.
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  • 40
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    Pure and applied geophysics 119 (1981), S. 1093-1099 
    ISSN: 1420-9136
    Keywords: Baltic Shield ; Deep seismic sounding ; Earthquakes in Finland
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    Topics: Geosciences , Physics
    Notes: Abstract The lithospheric models obtained for the Baltic Shield by using deep seismic soundings are discussed and results from different parts of the shield are compared with models achieved by the investigation of surface waves and of P to S converted waves. The results are found to agree rather well with each other particularly with regard to the first interface (at a depth of 10–15 km) and the whole thickness of the crust (c. 40 km). The macroseismic focal depth determinations of regional earthquakes are correlated with lithospheric structure. The main maximum in the focal depth distributions of Finnish earthquakes occur at a depth of 10–12 km. The geographical distribution of the earthquake epicentres suggests several seismo-active zones in the northern Baltic Shield. One new finding in this field concerns the Lapland zone, which runs in a north-westerly direction.
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    Pure and applied geophysics 119 (1981), S. 1116-1124 
    ISSN: 1420-9136
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    Topics: Geosciences , Physics
    Notes: Abstract A long-range Scandinavian seismic profile of August 1979 is subjected to a preliminary evaluation by means of the records of the permanent Swedish network of stations. The resulting travel times confirm those earlier adopted in the calculation of Swedish earthquakes for the period 1951–1976.
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    Pure and applied geophysics 119 (1981), S. 1107-1115 
    ISSN: 1420-9136
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    Topics: Geosciences , Physics
    Notes: Abstract The deep seismic sounding project ‘Blue Norma’ was carried out in the summer of 1977 in northern Scandinavia in order to investigate the deep structure of the Norwegian continental margin and the Caledonian mountain chain. During the measurements, by chance the core phase PKIKP of an earthquake at the New Hebrides was recorded with 30 seismic field stations along a profile through the central Caledonides. The results of the refraction seismic data, as obtained by a ray-tracing method, are presented and compared to the interpretation of the relative residuals of the PKIKP travel times. From both data sets a continentward down-dipping crust-mantle boundary is evaluated. From the interpretation of the refraction seismic measurements a crustal thickness of 32 km below the coastline and 42 km below the central mountain chain is obtained. The increase of the crustal thickness derived by the inversion of the travel-time residuals along this line amounts only to 6 km. This considerable discrepancy can only be explained by an eastward increasing seismic velocity in the mantle.
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    ISSN: 1420-9136
    Keywords: Carpathians ; Three-dimensional seismic modelling
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    Notes: Abstract The joint analysis performed for the Carpathian region from seismological data (three-dimensional fields of velocities, areas of concentration of earthquake foci in the Vrancea focal zone) and interpretation of DSS data and those of other geophysical fields have permitted to obtain new evidence for the earth's crust and mantle structure in this region.
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    Pure and applied geophysics 119 (1981), S. 1192-1196 
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    Pure and applied geophysics 119 (1981), S. 1197-1197 
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    Development genes and evolution 190 (1981), S. 208-214 
    ISSN: 1432-041X
    Keywords: Ascidian egg ; Ooplasmic segregation ; Cortical contraction
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    Topics: Biology
    Notes: Summary The egg cytoplasm of ascidian,Ciona intestinalis, segregates towards both the animal and vegetal poles within a few minutes of fertilization or parthenogetic activation with ionophore A23187. A constriction appears first on the egg surface near the animal pole and then moves to the vegetal pole. Carmine granules and spermatozoa attached to the egg surface move towards the vegetal pole with the movement of the constriction. Microvilli, which are distributed uniformly in unfertilized egg, disappear on the animal side of the constriction and became more dense on the vegetal side of the constriction. Transmission electron microscopy revealed that sub-cortical cytoplasm, containing numerous mitochondria and sub-cortical granules, moves towards the vegetal pole with the movement of the constriction and then concentrates into a cytoplasmic cap at the vegetal pole. An electron-dense layer appears in the cortex of the cap. The ooplasmic segregation and the cortical contraction were inhibited by cytochalasin B and induced by ionophore A23187. These observations suggest that ooplasmic segregation is caused by the cortical contraction which is characterised by a surface constriction and by the formation of an electron-dense layer.
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  • 47
    ISSN: 1432-041X
    Keywords: Mollusca ; Cleavage ; Junctions ; Interaction ; Development
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    Topics: Biology
    Notes: Summary In early cleavage stages ofLymnaea stagnalis, three kinds of intercellular junctions could be distinguished up to the sixth cleavage: intermediate, septate and gap junctions. The first two form “junctional belts” located on the cell border at the periphery of the embryo. For the purpose of our study we were most interested in gap junctions as they are alleged to be structures that allow cell-to-cell communication. Gap junctions first appear at the four cell stage. Up to the sixth cleavage no difference in the distribution pattern could be found between and within each of the four quadrants of the embryo. Some of the cell tiers along the animal-vegetal axis lack gap junctions either between the blastomeres within the tier or between the blastomeres from adjacent tiers. All gap junctions observed in freeze fracture replicas show plaques with an irregular IMP pattern. The average IMP diameter measures 12 nm (SD±2 nm). In stages fixed after the fifth cleavage, gap junctions are found between micromeres at the animal pole and the central 3D macromere. This is in agreement with the presumed interaction between these cells at this stage. The possibility of a transition of non-functional into functional gap junctions after the fifth cleavage is discussed.
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    Development genes and evolution 190 (1981), S. 221-225 
    ISSN: 1432-041X
    Keywords: Oogenesis ; Telotrophic Ovariole ; Vibrating Probe ; Electrophoretic Transport ; Dysdercus intermedius
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    Topics: Biology
    Notes: Summary Two systems of steady extra-cellular currents were found along the surface of the telotrophicDysdercus ovarioles by means of a vibrating probe. The first covers the subgerminal tropharium and all the previtellogenic follicles. The current leaves the 3 or 4 small follicles of early euplasmic growth stages laterally and enters the syncytial tropharium. We presume that a similar intracellular current flows between the trophoplasm and the ooplasm which are interconnected by narrow nurse strands. Preliminary intracellular measurements indicate a potential gradient within this continuous cytoplasm, the ooplasm being electropositive to that of the tropharium. This current system fits into a model of polarized intracytoplasmic transport by electrophoresis. It is possible to explain the well known directed and selective flow of RNA from the tropharium via the nurse strands into the oocytes by means of such a model. The second current system occurs around every one of the 2 to 8 vitellogenic follicles. The pattern is completely different from that described for the first system. In the vitellogenic stages the current enters the follicle laterally all along the now much extended surface. It is balanced by a strong peak current which leaves the interfollicular region. As data on intracellular currents are not yet avialable, it is only a matter of speculation whether the circuit is closed through the ooplasm or only by a tangential loop through the follicle epithelium. The possible significance of this second current system for vitellogenin accumulation and uptake by the vitellogenic oocytes is also uncertain as yet.
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    Development genes and evolution 190 (1981), S. 230-232 
    ISSN: 1432-041X
    Keywords: Regeneration ; Autotomy ; Black Widow spider ; Latrodectus variolus
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    Topics: Biology
    Notes: Summary Crustaceans, insects and to a lesser degree arachnids have been employed in regeneration studies. Amputation and ligation of the legs was used to determine occurring in a Black Widow spider complied with the developmental gradient model of regeneration. The occurrence of autotomy in this species was also documented. Amputation indicated the most proximal point from which regeneration of the leg could occur was the femoral mid-point. Amputation proximal to that area did not result in leg regeneration. Autotomy following amputation was not observed. Ligation of the legs resulted in autotomy when applied at and proximal to the mid-point of the tibia, increasing in frequency as more proximal segments were ligated. Autotomy always occurred at the trochanter-coxa joint. Autotomized legs did not regenerate. The regeneration observed complied with the developmental gradient model.
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    Development genes and evolution 190 (1981), S. 226-229 
    ISSN: 1432-041X
    Keywords: Early neurogenesis ; Mutants ; Drosophila melanogaster
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    Topics: Biology
    Notes: Summary Embryonic lethal mutations at the Notch locus are known to produce a conspicuous central nervous system hypertrophy accompanied by a hypotrophy of the epidermal sheath. We have studied several zygotic mutants belonging to four different autosomal complementation groups which produce the same phenotype. The embryonic development of the new mutants, as well as that of Notch, consists of an initial enlargement of the neurogenic region at the expenses of epidermal cell precursors. The possibility is discussed that these five loci are involved in the determination of neural and epidermal cell precursors.
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  • 51
    ISSN: 1432-041X
    Keywords: Endogenous lectin ; Chick ; Embryonic cell adhesion
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    Topics: Biology
    Notes: Summary Cells from the extraembryonic endoderm of the gastrulating chick embryo contain a β-d-galactoside-binding lectin inhibited by thiodigalactoside (TDG). When cell suspensions are cultured in stationary culture in the presence of exogenously added purified blastoderm lectin or TDG, their attachment to the substratum is delayed and decreased compared to controls. The cells take on a fibroblastic-like morphology and cell to cell contact becomes limited to localized areas of the cell surface. Many lectin or TDG-treated cells appear to be migrating over the substratum. This is in contrast to control cultures where the cells appear epithelial in morphology and tend to maximize their areas of apposition. These data suggest that the endogenous lectin may have a role to play in cell to substratum and cell to cell adhesion.
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    Development genes and evolution 190 (1981), S. 267-273 
    ISSN: 1432-041X
    Keywords: Pigment granules ; Redistribution ; Cortex ; Micromere formation ; Sea urchin embryos
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    Topics: Biology
    Notes: Summary Pigment granules (PGs) are embeded in the cortex of embryos of the Japanese sea urchins,Hemicentrotus pulcherrimus and Anthocidaris crassispina. PGs in the cortex actively retreated from the vegetal pole area at the 4-cell stage and then a notable PG-distribution gradient formed along the egg axis (the polar redistribution of PGs). The polar redistribution of PGs in the cortex occurred at the same time after fertilization even in solutions of microtubule disrupting reagents such as Colcemid, vinblastine sulfate or griseofulvin. Consequently, the polar redistribution of PGs was not associated with the microtubules. However, the polar redistribution of PGs was interrupted in seawater containing cytochalasin B (CB), dithiothreitol (DTT) or tetracaine, and the distribution pattern of PGs in the cortex was definitely disturbed. Moreover, CB, DTT and tetracaine altered the division pattern of vegetal blastomeres at the 4th cleavage which is normally unequal so that all the blastomeres divided equally. Microtubule disrupting reagents did not have such an effect on the cleavage pattern. Thus the cortical movement along the egg axis reflected by the polar redistribution of PGs seems to correlate with the micromere formation.
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    Development genes and evolution 190 (1981), S. 274-282 
    ISSN: 1432-041X
    Keywords: Bunodactis ; Anthozoa ; Regeneration ; Regulation ; Mirror image formation (Specularity)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary YoungBunodactis verrucosa Pennant at the 12 tentacle stage are employed to test the applicability of the polar coordinate model to coelenterate regeneration. The animals are cut along every radius into fragments of 3 to 9 segments. Most fragments are patent 3–4 weeks later, but small fragments have a higher mortality rate than large fragments. Some fragments do not regenerate and occasionally tentacles fuse, thereby reducing the number of segments. Small fragments tend to regenerate more tentacies than large fragments, but large fragments may regenerate great numbers of supernumerary tentacles. Twenty-two percent of the fragments restore the missing number of tentacles, while 76% of all fragments produce an even number of tentacles. Fragments restoring the correct numbers of tentacles show a marked tendency to form the correct tentacles (regulative regeneration). Fragments regenerating two less than the number of tentacles already present show a marked tendency to reproduce tentacles of the types already present (miror image formation). Other fragments produce missing segments (forward regeneration), or those already present (reverse regeneration) at lower frequencies. No fragments beginning or ending with the number 1 directive tentacle fail to regenerate entirely, while first cycle segments maximally remote from segment 1 are associated with the absence of regeneration. No fragments beginning or ending with the number 4 directive tentacle fail to undergo forward regeneration, regulate or produce a mirror image when the appropriate number of segments are regenerated. In contrast, segment 4 is associated with a low frequency of reverse regeneration, and second cycle segments cut away from immediate contact with segment 4 show an increase in the frequency of reverse regeneration. Controls through morphogenic substances rather than polar coordinates seem to explain these results. Such substances would control the number and direction of tentacle regeneration.
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    Development genes and evolution 190 (1981), S. 287-296 
    ISSN: 1432-041X
    Keywords: Mouse ; Morula ; Differentiation ; Commitment
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    Topics: Biology
    Notes: Summary The surface properties of newly formed, isolated 1/16 mouse blastomeres have been analyzed over the 10–12 h period prior to their division to 2/32 cells. Two populations of cells are formed at the 8- to 16-cell transition and their surface phenotypes vary with their relative position within the morula. Outer cells are polar, relatively non-adhesive and relatively large; inner cells are apolar, adhesive and smaller. The surface phenotypes of both inner and outer 1/16 cells are stable during culture for 11 h in isolation. However, the surface phenotypes can be induced to change by culture in combination with a second 1/16 cell, in a manner that is dependent upon the identity of the second cell. Two aggregated polar cells never flatten completely against each other, and both cells retain a clearly defined polar phenotype for 11–12 h. In aggregates of two apolar cells, cell outlines are lost as a result of intercellular flattening and microvilli are displaced away from areas of cell contact. However, if the two apolar cells are subsequently separated an even distribution of microvilli is restored. In most aggregates of an apolar and a polar cell, the polar cell envelops the apolar cell completely. These results are discussed in the context of the normal fate and potential of each cell type within the morula.
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    Development genes and evolution 190 (1981), S. 297-300 
    ISSN: 1432-041X
    Keywords: Myosins ; Drosophila ; muscle
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    Topics: Biology
    Notes: Summary Electrophoresis of myosin extracts from larvae and adult tissues ofDrosophila melanogaster under non-dissociating conditions indicate that two of the bands seen are myosins. They stain for Ca2+ ATPase activity and when cut and re-run under dissociating conditions are found to contain a myosin heavy chain that co-migrates with rabbit skeletal muscle myosin heavy chain. One of the forms of myosin seen is found primarily in extracts from the leg. The other is common to the adult fibrillar flight muscles and the larval body wall muscles. The electrophoretic evidence for two myosin types is strengthened by the histochemical demonstration of two myofibrillar ATPases on the basis of their lability to acid or alkali preincubation. The myofibrillar ATPase in the leg and the Tergal Depressor of the Trochanter (TDT) are shown to be relatively acid labile and alkali stable. The larval body wall muscles and the adult fibrillar flight muscles have an ATPase which is acid stable and alkali labile. This distribution of the two myofibrillar ATPase coincides with that predicted by electrophoresis of extracts from whole tissue and also locates the two myosins to specific muscle types.
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    Development genes and evolution 190 (1981), S. 304-304 
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    Development genes and evolution 190 (1981), S. 283-286 
    ISSN: 1432-041X
    Keywords: Transport ; Amino acids ; Valine
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    Topics: Biology
    Notes: Summary 14C-l-Valine uptake by intestinal segments of mice of various ages, ranging between 20-day fetuses and adults, was studied in vitro. 1 mMl-Valine was accumulated against a concentration gradient by processes which showed saturation kinetics. There appeared to be a two-fold increase ofl-valine accumulation after the 2nd postnatal day and a three-fold increase in adult mice. Fetal transport of valine only occurred at pH 7.4 but was not Na+ dependent. In contrast, valine transport became increasingly Na+ dependent and the pH optimum widened, ranging between 5–8. A series of amino acids, including representatives of the imino acid and dibasic groups, failed to inhibit valine uptake while leucine and isoleucine manifested mutual inhibition with valine. It is speculated that in the mouse intestine,l-valine is transported by at least two mechanisms, one functioning in the fetus, not requiring Na+, but pH dependent and another which developes postnatally, is Na-dependent and functions over a wide pH optimum.
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    Development genes and evolution 190 (1981), S. 301-303 
    ISSN: 1432-041X
    Keywords: Drosophila ; Geographic strains ; Chorion genes ; Electrophoretic variants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Further IF screening ofDrosophila melanogaster geographic strains has revealed a variant of the s19 major chorion protein. Developmental analysis of F1 hybrids indicates that the source of the variation is found in the structural gene for this protein. The linkage group of the variant gene was determined to be the third, and the gene was localized by several methods of recombination analysis. The s19 gene was found to be tightly linked to thesepia locus, as had been previously found for the s18 gene (Yannoni and Petri 1980). Lack of recombination between the s19 and s18 genes in double heterozygotes suggested that these two genes are within 0.3 map units of each other. Although more precise localization of the s19 gene failed, the s18 gene could be more specifically located to the right ofsepia, betweensepia andhairy. Contrary to our prediction (ibid.), the s19 and s18 genes have been found to be tightly linked in spite of the fact that they display somewhat different developmental stage specificity.
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    Development genes and evolution 190 (1981), S. 305-307 
    ISSN: 1432-041X
    Keywords: Hydra ; Budding ; Tumor promoter ; Phorbol
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    Topics: Biology
    Notes: Summary A low concentration of 12-O-tetradecanoylphorbol-13-acetate (TPA, 1.0 ng/ml) induced a transient inhibition of bud production in hydra which were fed daily. However, when hydra were starved following TPA-treatment, they produced further buds. Phorbol (1.0 ng/ml) and dimethyl sulfoxide (0.001%) did not influence bud production under either feeding or starvation conditions. These results indicate that TPA modulates asexual reproduction in hydra.
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    Development genes and evolution 190 (1981), S. 308-312 
    ISSN: 1432-041X
    Keywords: Drosophila ; ts-Suppressor mutant ; Glue proteins ; Intermolt puffs ; Electrophoresis
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    Topics: Biology
    Notes: Summary The l(1)su(f)ts67g mutation has been shown to suppress the developmentally regulated expression of glue protein genes at 30°C. Transferring mutant larvae to the restrictive temperature before the end of the second larval instar results in the absence or extreme reduction of glue protein synthesis while general protein synthesis is unaffected. At the same time, the three glue protein correlated chromosomal regions 3C, 25B, and 68C continue to show prominent puffs. The results suggest that the mutation may be affecting the processing or translatability of specific mRNAs rather than the translational machinery itself.
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    Development genes and evolution 190 (1981), S. 331-338 
    ISSN: 1432-041X
    Keywords: Insect oogenesis ; Poly(A)+ RNA ; Storage of maternal RNA ; Calliphora, Diptera
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    Topics: Biology
    Notes: Summary Ovaries ofC. erythrocephala synthesize large amounts of poly(A)+ and poly(A)− RNA during early and middle stages of oogenesis as shown by labelling with3H-uridine in vivo. After incubation for 1 h, a striking difference in the electrophoretic pattern of newly synthesized labelled poly(A)+ RNA and the poly(A)+ RNA present in sufficient amounts for optical density measurements (steady state poly(A)+ RNA) was observed. During early and mid-oogenesis, in the poly(A)− RNA fraction, ≧4S predominantly mature rRNA, 5S RNA and tRNA were labelled. These fractions were no longer synthesized during late oogenesis, whereas poly(A)+ RNA was labelled continously During oogenesis stage specific differences in the size distribution of newly synthesized and steady state poly(A)+ RNA were not obvious. However, different sizes of labelled poly(A)+ RNA species were detected in 0–2h old preblastoderm embryos, after injection of3H-uridine into females either 3–4 days (stage 3–4 of oogenesis) or 24 h before oviposition (stage 5–6 of oogenesis). This difference in RNA synthesis was related to the presence of active nurse cell nuclei. The poly(A)+ RNA fraction represents about 2–3% of the total RNA in both ovaries and freshly laid eggs as judged by measurements of optical density and radioactivity bound to oligo(dT). The length of poly(A)-segments in ovarian poly(A)+ RNA varied from about 30 to 200 nucleotides.
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  • 62
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    Keywords: Salivary gland ; Protein synthesis ; Larval development ; Drosophila melanogaster
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    Notes: Summary Patterns of protein synthesis in the salivary glands ofDrosophila melanogaster have been studied throughout late larval and prepupal development by pulse labelling the tissues with35S-methionine. Specific changes to the pattern of proteins synthesized during development are found and the significance of these changes is discussed in view of the known changes in gene (puffing) activity which occur at the same times. We review the problem of salivary gland function in “prepupal”Drosophila.
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    Development genes and evolution 190 (1981), S. 358-360 
    ISSN: 1432-041X
    Keywords: Morphogenesis ; Cellular differentiation ; Intercellular communication ; Embryogenesis ; Zebra fish
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    Notes: Summary The blastomeres of the zebra fish embryo can be classified into two types-cells stained densely (D) or lightly (L) with a mixture of toluidine and methylene (T-M) blue. The dense staining of D cells is largely due to the high density of mitochondria, rough endoplasmic reticulum and polyribosomes. The presence of partially dense stained cells during early blastula stage shows that L cells are transformed into D cells. That the yolk syncytial layer (YSL) plays some role in this transformation is suggested by the proximity of these cells to the YSL and by their distinct spatial orientation with densely stained cytoplasmic regions always facing towards the interior of the embryo.
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    Development genes and evolution 190 (1981), S. 361-364 
    ISSN: 1432-041X
    Keywords: Regulation ; Positional Information ; Regeneration ; Dictyostelium
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    Notes: Summary Regulating systems, that is, those which exhibit scale-invariant patterns in the adult, are supposed, to do so on account of interactions between cells during development. The nature of these interactions has to be such that the system of positional information (“map”) in the embryo also regulates. To our knowledge, this supposition regarding a regulating map has not been subjected to a direct test in any embryonic system. Here we do so by means of a simple and novel criterion and use it to examine tip regeneration in the mulicellular stage (slug) ofDictyostelium discoideum. When anterior, tip-containing fragments of slugs are amputated, a new tip spontaneously regenerates at the cut surface of the (remaining) posterior fragment. The time needed for regeneration to occur depends on the relative size of the amputated fragment but is independent of the total size of the slug. We conclude from this finding that there is at least one system underlying positional information in the slug which regulates.
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    Development genes and evolution 190 (1981), S. 365-369 
    ISSN: 1432-041X
    Keywords: Selector genes ; Determination ; Homoeotic mutations ; Drosophila melanogaster
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    Notes: Summary New alleles of thetrithorax locus have been isolated and analysed. The phenotypes of different allelic combinations confirm that a decrease or loss of function of the locus is responsible for homoeotic transformations of the adult thoracic and abdominal segments. Since neither these homoeotic transformations nor larval lethality are complemented by the previously described mutationRg-bx, it is concluded that the latter is an allele oftrithorax. The effect of near loss of function of thetrithorax locus after the completion of embryogenesis has been investigated by clonal analysis. This has produced two unexpected results: 1) there is a requirement for the activity of the locus after embryogenesis is completed; 2) the locus is required for the normal development of at least some mesothoracic structures. These results are discussed with respect to the selector gene hypothesis and other putative activator gene mutations.
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  • 66
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    Keywords: Drosophila ; Homoeotic mutants ; Ventral cord
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    Notes: Summary We describe a set of cells in the central nervous system of theDrosophila embryo which are restricted to the thoracic ganglia in the wildtype. Taking these cells as indication of thoracic identity, we find that the ventral cord of embryos homozygous mutant for different bithorax functions and for Polycomb undergoes homoeotic transformations equivalent to those observed in the larval cuticle.
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    Development genes and evolution 190 (1981), S. 374-378 
    ISSN: 1432-041X
    Keywords: Mouse teratocarcinoma ; Cell differentiation ; Nonhistone Proteins ; Two dimensional gel electrophoresis ; Silver staining
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    Notes: Summary The nonhistone protein pattern of four murine teratocarcinomas with different capacities for differentiation were compared: a multidifferentiated teratocarcinoma OTT2289, a nondifferentiated teratocarcinoma OTT2158, a teratocarcinoma-derived rhabdomyosarcoma TDR114, and a teratocarcinoma-derived neuroblastoma TDN2151. Their nonhistone proteins (NHP) were separated by differential salt extraction and hydroxyapatite chromatography into three fractions, NHP-I, NHP-II and NHP-III. Comparison of the NHP fractions by twodimensional gel electrophoresis in combination with a sensitive silver staining method reveals that there are several tumour line specific proteins in each NHP fraction. We suggest that specific NHP, which can be used as biochemical markers for each of the four investigated tumour lines, may be involved in cell lineage specific control of gene expression.
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    Development genes and evolution 190 (1981), S. 379-379 
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    Development genes and evolution 190 (1981), S. 380-380 
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    Development genes and evolution 186 (1979), S. 289-295 
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    Keywords: Morphometrics ; Somite ; Chick embryo
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    Notes: Summary Using the same methods as for the reconstruction of the thoracolumbar somite (Part I) the three-dimensional models of the lumbo-caudal and caudal somites of chick embryo (53 h of incubation) were obtained. The variations in volume, morphology, spatial position of the whole somites and of their components were studied and the development of the paraxial mesodermal structures is discussed.
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    Development genes and evolution 186 (1979), S. 1-25 
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    Keywords: Drosophila ; Leg imaginal disc ; Pattern duplication ; Genetic mosaics ; Compartments
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    Topics: Biology
    Notes: Summary l(1)su(f)mad-ts (mad) is a new temperature-sensitive (ts) lethal mutant ofDrosophila melanogaster which produces duplicated legs after temperature pulse treatment during larval development. The ts-lethality was studied in temperature experiments and genetic mosaics. Temperature pulses given during two distinct TSPs of larval development result in two different types of leg pattern duplication. “Total” differ from “partial” duplications with respect to the affected leg compartments and the orientation of the planes of symmetry which are perpendicular to the dorso-ventral and the proximo-distal leg axes in total and partial duplications, respectively. Genetic mosaic studies indicate (i) disc autonomy of leg pattern duplication, (ii) clonal separation of the anlagen of the two pattern copies, and (iii) clonal restriction along the antero-posterior compartment border in the two pattern copies of totally duplicated legs. The results suggest thatmad leg pattern duplication is caused by a change in positional information rather than by cell death and subsequent regeneration. Our data are compatible with the assumption that during normal development the leg disc cells acquire information about their position within the disc with respect to the different leg axes independently and at different times.
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    Development genes and evolution 186 (1979), S. 81-85 
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    Keywords: rDNA ; Oocytes ; Acipenser ; In situ hybridization
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    Notes: Summary In situ hybridization has been performed in sections through ovaries ofAcipenser ruthenus andAcipenser güldenstädti in order to detect the rDNA sequences. Hybridization resulted in specific labelling of the “caps” of extrachromosomal DNA present in pachytene oocyte nuclei and of the chromatin granules distributed beneath the nuclear envelope in early diplotene nuclei. In the same sections, the nuclei of all ovarian cells in both species (oogonia, leptotene, and zygotene stage oocytes, follicular cells, connective tissue cells) showed a very low, but similar labelling. Amplification of genes for rRNA thus occurs at the pachytene stage in early oogenesis ofAcipenseridae. No rDNA amplification could be detected in the previous stages.
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    Development genes and evolution 186 (1979), S. 91-94 
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    Keywords: Xenopus egg ; Fertilization ; Surface wave ; Time-lapse cinematography
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    Topics: Biology
    Notes: Summary Shortly after local artificial insemination, but well before egg rotation,Xenopus eggs show a wave-like propagation of dark-light-dark zones from the site of sperm entrance. This presumably reflects the movement of the front of cortical granule breakdown.
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    Development genes and evolution 186 (1979), S. 95-102 
    ISSN: 1432-041X
    Keywords: Vegetalization ; Determination ; Electrophoresis ; Protein systhesis ; Sea urchin
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    Notes: Summary Strongylocentrotus purpuratus embryos were reared in 0.025 M LiCl, which causes commitment to vegetalized development within 5 h after treatment begun at fertilization. Treated and control embryos were labelled with35S-methionine for 3 h intervals from 2–14 h, solubilized, and subjected to 2-dimensional polyacrylamide gel electrophoresis. Comparison of autoradiographs of the gels, in which over 400 proteins can be detected, indicate that while LiCl treatment causes a short delay in the initiation or cessation of synthesis of a few proteins, no qualitative or major quantitative differences can be detected between control and treated embryos. Normal gastrulae and vegetalized exogastrulae labelled 38 h after fertilization have several differences in patterns of protein synthesis. We conclude that the early determinative events involved in vegetalization are not reflected in detectable differences in the pattern of protein synthesis.
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    Development genes and evolution 187 (1979), S. 245-254 
    ISSN: 1432-041X
    Keywords: Multiple monster ; Cell dissociation ; Horseshoe crab
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    Notes: Summary When horseshoe crab embryos were treated with NaHCO3 at the developmental stage when the germ disc appears, multiple embryos were formed. NaHCO3 may effect the formation of multiple embryos by binding Ca2+ ions of the embryo since multiple embryos were also formed by treatment with Ca2+ free sea water. The treatment caused the blastoderm layer to tear. When the embryos were returned to normal sea water after the treatment, the blastoderm recovered. Some cell masses, probably derived from the germ disc or its prospective cells, formed during the process of the recovery. Each cell mass developed into an embryo.
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    Development genes and evolution 187 (1979), S. 269-282 
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    Keywords: Xenopus laevis ; Early embryo ; RNA synthesis ; Lithium ; Polysomes
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    Notes: Summary The treatment ofXenopus early embryos with lithium chloride produces exogastruale — embryos which fail to gastrulate normally and in which the rates of cell division are reduced. In the present study estimations of incorporations of (5-3H) uridine and the specific activities of the 5′-ribonucleotide precursor pools showed that exogastrulae have higher rates of RNA synthesis per cell than control neurulae. Sub-cellular fractionations showed that a greater proportion of labelled RNA was retained in the nuclei of exogastrulae than of neurulae, while neurulae showed a greater incorporation into polysomes.
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    Development genes and evolution 187 (1979), S. 255-266 
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    Keywords: Yolk proteins ; Hormonal control ; Electrophoresis ; In vivo culture ; Drosophila
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    Notes: Summary Immature ovaries ofDrosophila mercatorum were injected into young larvae and into adult males ofD. mercatorum, D. melanogaster, D. hydei, D. virilis, andZaprionius vittiger. These homo- and heteroplastic transplantations allow normal vitellogenesis to occur in the donor ovary. By SDS gel electrophoresis, we identified the major species-specific yolk proteins of mature eggs (stage 14) which were exclusively of donor-specific origin. Other experiments withD. hydei andZ. vittiger showed that, when females were used as hosts, the host-specific yolk proteins became incorporated into the donor eggs. When two immature ovaries, one ofD. mercatorum and one ofD. hydei, were co-cultured in males, again only the donor-specific yolk proteins were found in the mature eggs implying that these yolk proteins were not released into the host hemolymph. A parthenogenetic strain ofD. mercatorum was used to demonstrate the ability of transplanted immature ovaries to produce viable eggs which can give rise to fertile adults. The role of the species-specific yolk proteins is discussed with respect to the dual origin of these proteins during normal vitellogenesis, i.e., an autonomous synthesis within the ovary itself in addition to the well-known production by the fat body. Further experiments with pupae as hosts indicate that even in the absence of juvenile hormone and in the presence of high doses of ecdysone, vitellogenesis can proceed within the donor ovary. Based on these experiments, a new hyopthesis on the hormonal control of vitellogenesis inDrosophila is presented. We propose that yolk proteins derived from the fat body are controlled by juvenile hormone, whereas the independent and autonomous vitellogenesis within the ovary itself is controlled by endogenously synthesized ecdysone.
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    Development genes and evolution 187 (1979), S. 307-321 
    ISSN: 1432-041X
    Keywords: Ciliate ; Morphallactic regeneration ; Shape regulation
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    Notes: Summary Following transection ofDileptus regulation of cell shape and cortical pattern was studied during regeneration in an attempt to understand the interrelations of these two regulation processes. The cell ofDileptus consists of two regions, proboscis and trunk, with the oral structures marking the border between them. The isolated proboscis is able to reorganize into a complete and correctly proportioned organism and the course of this reorganisation has been observed. Correct cell proportions take more than 24h to be established. Three hours after the operation the new border between proboscis and trunk is formed. Initially, the proportions of the cell are far from normal; moreover, they can temporarily change towards a more abnormal state. This indicates that the localisation of the border between the two cell regions and the assessment of final cell proportions are separate phenomena possibly controlled by different mechanisms.
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    Development genes and evolution 187 (1979), S. 283-305 
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    Keywords: Inhibitors ; Insect embryogenesis ; Oogenesis ; Permeabilisation ; Two-dimensional gel electrophoresis
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    Topics: Biology
    Notes: Summary Embryos of the chironomid midgeSmittia spec. were permeabilized with sodium hypochlorite and octane. Uptake of labeled uridine and amino acids suggested that these compounds are actively transported across the plasma membrane. Before blastoderm formation, uridine was incorporated at low levels into nuclear DNA and mitochondrial RNA. After blastoderm formation, uridine was incorporated rapidly, mostly into cytoplasmic RNA including both ribosomal RNA precursors and poly(A)-containing RNA. Protein synthesis was observed throughout early embryogenesis. By measuring incorporation of labeled amino acids and internal amino acid pool sizes, we found that the rate of protein synthesis increased with development. Experiments with inhibitors of transcription indicated that proteins synthesized before blastoderm formation were translated from maternal mRNA. During blastoderm stages, embryonic mRNAs seemed to replace maternal mRNAs. Proteins synthesized during short incubation periods in vivo were separated by two-dimensional gel electrophoresis. After blastoderm formation, several new proteins were found that could not be detected at earlier stages.
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    Development genes and evolution 187 (1979), S. 323-328 
    ISSN: 1432-041X
    Keywords: Nerve-depletedhydra ; Morphogenetic substances
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    Notes: Summary By a double colchicine treatment the nerve-cell population ofhydra was reduced to less than 1% of the normal complement. Such severely nerve-depletedhydra contained normal or higher than normal concentrations of head activator, head inhibitor, foot activator and foot inhibitor which in normal animals are produced by nerve cells. According to typical chromatographic properties all four morphogenetic substances were chemically identical to those found in normal animals. It is suggested that in nervedepletedhydra the epithelial cells, as the only remaining cell type, have taken over the morphogen-producing function of nerve cells.
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  • 81
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    Keywords: Glue proteins ; Secretory proteins ; Drosophila
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    Notes: Summary Salivary gland cells of members of theDrosophila melanogaster group (from four different subgroups) were examined electron microscopically and histochemically during the late larval period of development. The secretory product, which is supposed to be utilized as ‘glue’ at the time of puparium formation, appears, by analogy to Palade and Jamieson's results, to be synthesized partially in the rough endoplasmic reticulum (RER) and partially in the Golgi complex. The latter is also the usual site of the packaging of the product into secretory granules, except in the case of one of the secretory granule components ofD. lucipennis. The phylogenetic relationships among the subgroups, implied by the morphological appearance of the secretory granules, fit well with the existing phylogenetic relationships within the group. The secretory granules of each species have their own morphological features; granules of species of the same subgroup share some of these features. Secretion occurs from the cells via exocytosis during which the morphology of the secretory granules changes. Light microscope examination of PAS (Periodic Acid-Schiff reaction) stained glands shows a strong positive reaction in most species, with the exception of the species of thesuzukii subgroup which show a weak, or a negative reaction (D. rajasekari). Electron histochemical localization of polysaccharides in the secretory granules was possible inD. melanogaster and the species of theananassae subgroup.
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    Development genes and evolution 187 (1979), S. 355-366 
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    Keywords: Mollusca ; Embryology experimental ; Development analysis ; Dentalium ; Invertebrate development
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    Topics: Biology
    Notes: Summary Each primary micromere and macromere of the D-quadrant ofDentalium was deleted, through the mesentoblast stage, to investigate the way in which the polar lobe cytoplasm exerts its influence on development.-D and -1D embryos form an apical tuft but no posttrochal structures.-2D embryos form an apical tuft and a reduced posttrochal region without a shell. -3D and -4D are externally similar to control embryos. -1d embryos and -1c embryos have an apical tuft with a reduced number of cilia. Embryos in which both 1c and 1d are deleted lack the apical tuft.-2d embryos lack shell and most other posstrochal structures. -3d and-4d embryos appear externally equivalent to controls. The polar lobe cytoplasm exerts its influence sequentially, and as inIlyanassa the maximal effect is at the third quartet stage.
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    Development genes and evolution 190 (1981), S. 22-26 
    ISSN: 1432-041X
    Keywords: Vitellogenesis ; Follicle proteins ; Juvenile hormone ; Locusta
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    Topics: Biology
    Notes: Summary Insoluble proteins from the maturing follicle ofLocusta migratoria were analyzed by SDS-PAGE. A reproducible pattern of low molecular weight proteins was observed. Five of these proteins did not correspond to yolk or haemolymph proteins. At least two of these show marked quantitative changes during oocyte development. By in vitro incubation of follicles and fat body with a labelled precursor, and by the identification of the labelled polypeptides by SDS-PAGE, we could demonstrate that these two proteins are synthesized only during the time of vitellogenin uptake. This protein is probably a follicle product necessary for yolk formation. The other protein might be necessary for vitelline membrane and/or chorion formation.
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    Development genes and evolution 190 (1981), S. 11-21 
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    Keywords: Drosophila ; Imaginal discs ; Ecdysteroid ; Lethal mutant ; Morphogenesis
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    Topics: Biology
    Notes: Summary Imaginal disc development in the non-pupariating lethall(1)npr-1, a mutant that maps to an ecdysone early puff site, is studied in situ, in vitro and in transplanted discs. Disc development is slightly abnormal from the middle of the third instar with severe abnormalities appearing after the rise in 20-hydroxyecdysone that triggers metamorphosis. The mutant discs only partly evaginate and do not undergo any of the detailed morphological changes characteristic of metamorphosis. Treatment of the mutant dises in vitro with colcemid and trypsin facilitates evagination but the appendages remain morphologically abnormal. A number of differentiative processes occur in mutant discs in situ and in discs transplanted into wild type hosts in spite of the absence of normal morphogenesis. Implications of the observations for normal disc development are discussed. Possible modes of action of thel(1)npr-1 gene are also discussed in light of the observation that the mutant gene maps to a locus which is thought to have a regulatory function in development.
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    Development genes and evolution 190 (1981), S. 1-10 
    ISSN: 1432-041X
    Keywords: Drosophila ; Grandchildless ; Pole cells ; ts-mutant ; Cytoplasmic determinant
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    Topics: Biology
    Notes: Summary Two temperature-sensitive sex-linkedgrandchildless (gs)-like mutations (gs(1)N26 andgs(1)N441) were induced by ethylmethane sulphonate inDrosophila melanogaster. They complemented each other and mapped at two different loci (1−33.8±0.7 forgs(1)N26 and 1−39.6±1.7 forgs(1)N441), which were not identical to those of any of thegs-like mutants reported in earlier work. Homozygous females of the newly isolated mutants produced eggs that were unable to form pole cells and developed into agametic adults. Competence of the embryos to form pole cells was not restored by wild-type sperm in either mutant; that is, the sterility caused by these mutations is controlled by a maternal effect. Fecundity and fertility ofgs(1)N26 females were low, and their male offspring showed a higher mortality than that of female offspring, causing an abnormal sex ratio. The frequency of agametic progeny was 93.1% and 55.8%, when the female parents were reared at 25° C and 18° C, respectively. In eggs produced by thegs(1)N26 females reared at 25° C, the migration of nuclei to the posterior pole was abnormal, and almost no pole cell formation occurred in these egg. Furthermore, half of these eggs failed to cellularize at the posterior pole. When the females were reared at 18° C, almost all of the eggs underwent complete blastoderm formation, and in half of these blastoderm embryos normal pole cells were formed. In the other mutant,gs(1)N441, the fecundity and fertility of the females were normal. The agametic frequency in the progeny was 70.8% and 18.6% when the female parents were reared at 25° C and 18° C, respectively. In the eggs laid by females reared either at 25° C or at 18° C, the migration of nuclei to the periphery and cellularization proceeded normally; nevertheless, in the majority of the embryos no pole cell formation occured at the stage when nuclei penetrated into the periplasm. When the females were reared at 18° C, some of the embryos from these females formed some round blastoderm cells with cytologically recognizable polar granules and nuclear bodies, which are attributes of pole cells. The temperature sensitive period ofgs(1)N441 was estimated to extend from stage 9 to 13 of King's stages of oogenesis.
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    Development genes and evolution 190 (1981), S. 233-236 
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    Keywords: Sulphate ; Glycosaminoglycan ; Autoradiography ; Gastrulation ; Chick
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    Topics: Biology
    Notes: Summary Chick blastoderms were cultured for 2 h in the presence of35S-sulphate. The distribution of the grains after light microscope autoradiography was compared in blastoderms during the elongation and during the shortening of the primitive streak. A uniform labeling was observed over the cells in both groups. Accumulation of grains was present in both groups at the ventral side of the upper layer, where transmission electron microscope studies have revealed a basal lamina. An additional accumulation of grains occurred over the cells and in the extracellular spaces of the head process and of the rostral part of blastoderms with shortening primitive streaks. This positivity could be correlated with the presence of ingressing and recently ingressed notochordal cells. Treatment of the sections with chondroitinase ABC and/or HNO2 before dipping in the nuclear emulsion demonstrated that at least chondroitin sulphate and N-sulphated heparan sulphate were present.
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    Development genes and evolution 190 (1981), S. 237-240 
    ISSN: 1432-041X
    Keywords: DNA replication ; Polytene salivary gland nuclei ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Combined cytophotometric and autoradiographic experiments are performed on individual polytene salivary gland nuclei of X/X-female and X/Y-male larvae ofDrosophila melanogaster, DNA measurements of unlabeled nuclei reveal complete douplings of all 4C DNA quantity during polytenization. These new data do not agree with the hypothesis of heterochromatic underreplication.
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  • 88
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    Development genes and evolution 190 (1981), S. 241-243 
    ISSN: 1432-041X
    Keywords: Leg discs ; In vitro evagination ; Proline ; Glutamine ; Salivary Glands
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A method of staging late third instar larvae on the basis of salivary gland morphology is described. Using this technique, we investigated stage related amino acid requirements forDrosophila leg disc evagination in vitro. It was found that the requirement for glutamine lasted longer than that of proline. The staging technique should help in the detailed exploration of the late 3rd instar time period in order to bridge the gap between biochemistry and morphogenesis in the initiation of disc evagination.
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  • 89
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    Development genes and evolution 190 (1981), S. 245-251 
    ISSN: 1432-041X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In the maternal-effect embryonic lethalmat(3)6, although cell formation occurs only at the poles, posterior blastoderm cells give rise to a posterior midgut rudiment (PMG) that undergoes extension movements similar to those in normal embryos (Rice and Garen 1975). Inmat(3)6 embryos, PMG cells retain cytoplasmic continuity with the yolk sac during early extension, and a microfilament system is present in the yolk sac beneath and anterior to the PMG. This correspondence between normal and mutant embryos in what we have postulated to be essential structural components of the morphogenetic system (Rickoll and Counce 1980) supports our interpretation that the yolk sac has a causal role in early germ band extension. Further, extension movements in these mutant embryos provide evidence that neither large-scale changes in cell shape nor cell interactions are essential for PMG extension and invagination.
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  • 90
    ISSN: 1432-041X
    Keywords: Vitelline coat ; Oogenesis ; Differentiation ; Tunicates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have studied the differentiation of the vitelline coat (VC) of the ascidianCiona intestinalis. In the young previtellogenic oocyte the vitelline coat precursor material (VCPM) makes its first appearance as patches of fibrous material in close apposition to the outer surface of the oocyte. The presence of subcortical vescicles containing a fuzzy electron-dense material and their opening into the oocyte surface parallels the formation of VCPM. Numerous microvillar-like structures emerge from the oocyte surface. When the VCPM completely surrounds the oocyte the microvilli are withdrawn. An overall increase of VCPM parallels the growth of the oocyte. The next step in the differentiation of the vitelline coat consists in the packing of the constituent fibrils in a dense layer at its outer surface, i.e. the one in contact with the follicle cells. At this time the VC is penetrated by microvilli protruding both from the oocyte and follicle cells. The VC reaches its final structure and thickness at the time the test cells are extruded into the perivitelline space. The participation of the follicle cells in VC organization is also discussed.
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  • 91
    ISSN: 1432-041X
    Keywords: Neural induction ; Lectins ; Cell architecture ; Cell surface ; SEM
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Scanning electron microscopic studies revealed that Concanavalin A (ConA) induces characteristic changes of the cell surface and the cell architecture of the presumptive ectoderm associated with differentiation into neural tissues. In Con A-treated cells, the filopodia with which cells were connected to each other disappeared from the interior (blastocoelic) surface and the cellular adhesivity decreased significantly. Thereafter, the cells underwent from those of the control explants. After cultivation for 60 h, a certain pattern of cell arrangement, which resembled the architecture of neural tissues, was observed among randomly arranged cells in the explants treated with Con A. The morphological changes specifically observed in Con A-treated explants were different from those found in explants treated with succinyl Con A (S-Con A) orDolichos biflorus agglutinin (DBA), which is unable to induce formation of the neural tissues. The molecular organization of the plasma membrane appears to be important in the mechanism of neural induction.
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  • 92
    ISSN: 1432-041X
    Keywords: Fowl embryo ; Catecholamine accumulation ; Formaldehyde-induced-fluorescence ; Non-neural tissues ; Morphogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Catecholamines (CA) were localized in stage 11–34 domestic fowl embryos by the formaldehyde-induced fluorescence (FIF) method after exposure in vivo or in vitro to CA (noradrenaline or α-methylnoradrenaline), or the CA precursorl-DOPA. The effects of drugs known to alter CA metabolism in the adult were also investigated. Negligible FIF was observed in embryos which had not been exposed to CA. After CA loading, FIF could be seen in the neural tube and in non-neural tissues such as the notochord and gut mesenchyme and to a lesser degree in suprarenal area tissue, liver endothelium, sclerotome, and myotome. This FIF was inhibited by desmethylimipramine, a blocker of adult neuronal CA uptake (Uptake1), but not by corticosterone, a blocker of adult extraneuronal CA uptake (Uptake2). The notochord, dorsal pancreas and some blood cells were fluorescent afterl-DOPA loading, and this FIF could be greatly diminished by the DOPA decarboxylase inhibitor RO4-4602. The pattern of FIF in the axial structures (neural tube and notochord) correlated with axial flexure in both position and time, and the intensity of fluorescence was strongest cranially and caudally, where flexure is most pronounced. The FIF in gut mesenchyme cells was closely related to the movement of the intestinal protals during early gut tube formation, and to the regions of the developing intestine that undergo intense morphogenesis during their early formation.
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  • 93
    ISSN: 1432-041X
    Keywords: Aging ; Neural competence ; Trunk organizer ; Cynops pyrrhogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The effect of aging on the neural competence of the presumptive ectoderm of the early gastrula, and the effect of aged ectoderm on the differentiation of the still uninvaginated dorsal blastoporal lip at the small yolk-plug stage — representing the trunk organizer — were examined by the sandwich method inCynops pyrrhogaster. The presumptive ectoderm to be used as reaction system was taken from 0 to 36 h exogastrulae obtained by operation at the early gastrula stage and combined with trunk organizer. In the 0 to 12 h explants typical trunktail structures were formed. With further aging of the presumptive ectoderm a decrease in frequency of spinal cord, notochord, and muscle and a simultaneous increase in frequency of mesenchyme and mesothelium were observed. In the 30 and 36 h explants neural competence had largely disappeared, the frequency of notochord and muscle become very low and their differentiation very poor, whereas the frequency of mesenchyme and mesothelium reached very high levels. We infer a reciprocal relationship between the induced spinal cord and the differentiation of notochord and muscle, as well as a transformation of notochordal material into mesenchyme and mesothelium under the influence of the aged ectoderm. The mode of action of the trunk organizer in normal development is discussed.
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  • 94
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    Development genes and evolution 187 (1979), S. 25-34 
    ISSN: 1432-041X
    Keywords: Mesoderm formation ; Morphogenetic movement ; Trunk organizer ; Cynops pyrrhogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The exact localization of the presumptive trunk organizer was determined by means of vital staining at the initiation of gastrulation (0 h embryo) and subsequently in 6, 9, 12 and 24 h embryos. The progressive changes in the self-differentiation and inductive capacity of the trunk organizer were studied in isolation cultures (sitting drop) and in sandwich cultures with competent gastrula ectoderm. In the 0 and 6 h embryo cultures the excised trunk organizer predominantly formed atypical ectoderm. A dramatic change in differentiation and inductive capacity occurred in the 9 h embryo. The positive cases — 83% of the isolation and 50% of the sandwich cultures — mainly formed notochord and somites, accompanied by spinal cord and hindbrain in the sandwich cultures. Although no further change in self-differentiation occurred from that time onwards, a gradual increase in inductive capacity was recognized.
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  • 95
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    Development genes and evolution 185 (1979), S. 333-346 
    ISSN: 1432-041X
    Keywords: Chick embryo ; Limb bud ; Ultrastructure ; Cell death
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The ultrastructural changes in the wing bud afterapical ectodermal ridge (A.E.R.) removal was studied to re-examine the issue of distal mesenchymal cell death. The A.E.R. of the right wing bud was removed microsurgically from chick embryos of stages 18 to 22 (HH 1951). The wing buds were examined at three hour intervals up to twelve hours after the operation with light, transmission and scanning electron microscopy. The main findings were: (1) Immediate and temporary shrinkage of the mesenchymal extracellular space 100 to 150 μm and chromatin condensation in the cells 50 to 75 μm from the wound. (2) Death of ectodermal and mesenchymal cells in the immediate vicinity of the wound. (3) Formation of a single squamous-like layer of mesenchymal cells to cover the wound. (4) Occasional evidence of cell death in the distal mesenchyme at later times after the operation. The pattern of cell death observed suggests only a traumatic etiology, and gives little evidence for the postulated developmental significance of cell death following A.E.R. removal.
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  • 96
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    Development genes and evolution 185 (1979), S. 347-362 
    ISSN: 1432-041X
    Keywords: Ovary ; Silkworm ; Sulfate ; Glucosamine ; Mucopolysaccharide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary InHyalophora cecropia the intercellular spaces of the follicles contain during vitellogenesis a matrix that can be labelled eitherin situ or in culture with35S-sulfate and3H-glucosamine. The matrix was demonstrated by autoradiography and also by treating follicles for 15 min with pronase, which released TCA-soluble matrix fragments with molecular weights of up to 2×106 daltons. Testicular hyaluronidase degraded the high molecular weight fragments, and thus it is probable that they are chondroitin sulfate-like mucopolysaccharides. With the termination of vitellogenesis new matrix is no longer deposited, and the pre-existing material is disassembled. The sulfated matrix may account for the patency of the intercellular diffusion channels essential for blood protein uptake and also for the low level, extracellular binding of blood proteins that characterizes the vitellogenic follicle inHyalophora.
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  • 97
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    Development genes and evolution 186 (1979), S. i 
    ISSN: 1432-041X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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  • 98
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    Development genes and evolution 185 (1979), S. 363-370 
    ISSN: 1432-041X
    Keywords: Drosophila ; Imaginal discs ; Pattern formation ; β-ecdysone ; Tissue culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Pairs of eye-antennal discs, attached to the cephalic ganglia, were cultured in vitro with a concentration of β-ecdysone optimal for imaginal differentiation. The eye-antennal discs fused to form a vesicle inside which the antennae were partially everted, and on the inner surface of which imaginal structures differentiated. The epithelium of the discs was continuous, and an integrated pattern of bristles and hairs differentiated in vitro. In particular, the median ocellus, a unified structure derived partially from each disc, differentiated normally.
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  • 99
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    Development genes and evolution 186 (1979), S. 129-137 
    ISSN: 1432-041X
    Keywords: Oogenesis ; Coelomic fluid ; Sex peptides ; Glycoproteine synthesis ; Perinereis cultrifera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Two peptides (B1 and B2) have been isolated from the coelomic fluid ofPerinereis cultrifera. These peptides are absent in sexually undifferentiated animals. They appear and become abundant during the oocyte submaturity stage. When B1 and B2 are simultaneously injected into very young females, they stimulate an important biosynthesis of oocyte glycoconjugates (certical alveoli). Injected separately, B1 or B2 leads to an oocyte structure similar to that of an anhormonal state. The modes of these actions were discussed.
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  • 100
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    Development genes and evolution 186 (1979), S. 103-114 
    ISSN: 1432-041X
    Keywords: Insect ; Ecdysteroids ; Ovarian development ; Embryonic development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary InBlaberus craniifer, the maturation of the oocytes is accompanied by morphological modifications of the surrounding follicular cells and by variations in the ecdysteroid titre. Before the follicular cells form the chorion, they synthesise ecdysteroids which pass into the terminal oocytes to be stored. During the secretion of the chorion, before the release of the oocytes, one observes a decrease of the ecdysteroid titre in the ovaries. The hormonal titres in ovaries and haemolymph fluctuate in parallel, probably because ovaries “leak” into the haemolymph. The terminal oocyte of each ovariole is deposited into the incubating pouch where the entire embryonic development takes place. There is first a decrease of the ecdysteroids synthesised by the follicular cells and stored in the eggs. One then observes 3 ecdysteroid peaks during each of the 2 cycles of the development. During the first cycle, the first peak coincides with the end of the metamerisation, the second peak with the secretion of the first cuticle and the third with the transition between the first and the second cycle. For the second cycle, the first peak coincides with the loss of the capacity to regenerate, the second with the secretion of the second cuticle and the third with the hatching period. The third peak of each of these 2 cycles is atypical compared with what is known of the larval cycles. The analysis of the hatching peak has shown that it is principally composed of a compound more polar than α-ecdysone
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