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  • Springer  (43,712)
  • 1995-1999
  • 1980-1984  (43,712)
  • 1981  (43,712)
  • 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
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    Pure and applied geophysics 119 (1981), S. 966-977 
    ISSN: 1420-9136
    Keywords: Streamer interactions
    Source: Springer Online Journal Archives 1860-2000
    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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  • 8
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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
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    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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  • 9
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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
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    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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  • 10
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    Pure and applied geophysics 119 (1981), S. 1024-1036 
    ISSN: 1420-9136
    Keywords: Electromagnetic scattering ; VLF electromagnetic prospection
    Source: Springer Online Journal Archives 1860-2000
    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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  • 11
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    Pure and applied geophysics 119 (1981), S. 1077-1092 
    ISSN: 1420-9136
    Keywords: Seismic hazard estimation ; Bohemia
    Source: Springer Online Journal Archives 1860-2000
    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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  • 12
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    Pure and applied geophysics 119 (1981), S. 1125-1133 
    ISSN: 1420-9136
    Keywords: Seismicity and crustal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    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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  • 13
    ISSN: 1420-9136
    Keywords: Caucasus ; Three-dimensional seismic modelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    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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  • 14
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    Pure and applied geophysics 119 (1981), S. 901-912 
    ISSN: 1420-9136
    Keywords: Monsoon depression ; Cyclogenesis ; Barotropic instability
    Source: Springer Online Journal Archives 1860-2000
    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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  • 15
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    Pure and applied geophysics 119 (1981), S. 922-933 
    ISSN: 1420-9136
    Keywords: Extreme precipitation ; Tropical meteorology
    Source: Springer Online Journal Archives 1860-2000
    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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  • 16
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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
    Source: Springer Online Journal Archives 1860-2000
    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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  • 17
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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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  • 18
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    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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  • 19
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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
    Source: Springer Online Journal Archives 1860-2000
    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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  • 20
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    Pure and applied geophysics 119 (1981), S. 1116-1124 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    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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  • 21
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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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    Topics: Geosciences , Physics
    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 
    ISSN: 1420-9136
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    Pure and applied geophysics 119 (1981), S. 1197-1197 
    ISSN: 1420-9136
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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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  • 26
    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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  • 30
    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)
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    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 
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    Keywords: Drosophila ; Geographic strains ; Chorion genes ; Electrophoretic variants
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    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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  • 41
    ISSN: 1432-041X
    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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    Topics: Biology
    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 
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    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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  • 45
    ISSN: 1432-041X
    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 190 (1981), S. 22-26 
    ISSN: 1432-041X
    Keywords: Vitellogenesis ; Follicle proteins ; Juvenile hormone ; Locusta
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    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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    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 
    ISSN: 1432-041X
    Keywords: Sulphate ; Glycosaminoglycan ; Autoradiography ; Gastrulation ; Chick
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    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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  • 53
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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
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    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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    Development genes and evolution 190 (1981), S. 241-243 
    ISSN: 1432-041X
    Keywords: Leg discs ; In vitro evagination ; Proline ; Glutamine ; Salivary Glands
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    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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    Development genes and evolution 190 (1981), S. 245-251 
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    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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  • 56
    ISSN: 1432-041X
    Keywords: Vitelline coat ; Oogenesis ; Differentiation ; Tunicates
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    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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  • 57
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    Keywords: Neural induction ; Lectins ; Cell architecture ; Cell surface ; SEM
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    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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  • 58
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    Keywords: Fowl embryo ; Catecholamine accumulation ; Formaldehyde-induced-fluorescence ; Non-neural tissues ; Morphogenesis
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    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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    Development genes and evolution 190 (1981), S. ii 
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    Development genes and evolution 190 (1981), S. 27-32 
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    Keywords: Locusta ; Vitellogenesis ; Immunofluorescene ; Follicle proteins
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    Development genes and evolution 190 (1981), S. 40-48 
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    Keywords: Bristle pattern ; Clones ; Cell competition ; Notch wing ; Drosophila hydei
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    Notes: Summary The bristle pattern along the anterior margin ofNotch (N1-22.3) wings ofDrosophila hydei and the occurrence ofyellow (y 1–38.8) marked clones induced by X-ray irradiation during various larval stages are described. UnirradiatedN/N + wings show gaps (‘notches’) in the longitudinal bristle rows along the 1st longitudinal vein, with tufts of bristles particularly near gaps. X-ray irradiation increases the number and total length of the gaps. The patterning of bristles along the margin depends on theN (+) genotype of the induced clones. RecombinantN +/N + clones from irradiated wings show excessive growth with an autonomous wildtype bristle pattern. Characteristically, these clones do not respect the dorso-ventral compartment boundary along the wing margin, do not follow an exponential (2n) growth pattern, tend to fill the gaps with bristles and theiryellow medial row bristles are less often interspersed withy + bristles than described forN +/N + wings. HomozygousN appears to be a cell lethal condition inD. hydei as it is inD. melanogaster. When y clones were kept phenotypicallyNotch (viz.,N/N/N +) as the background cells, we found a lower number ofy bristles, a lower percentage of mosaic wings but also a reltive deficiency ofy + interspersions. The latter is discussed in relation to a possible clonal originof the notches.
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    Development genes and evolution 190 (1981), S. 65-65 
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    Development genes and evolution 190 (1981), S. 58-59 
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    Keywords: Gonadotropins ; Thyrotropin ; Adrenocorticotropin ; Chick embryo ; Gonad-development
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    Notes: Summary Gonadotropins (FSH+LH) and thyrotropin (TSH) stimulated the development of 12-day embryonic gonads, whereas adrenocorticotropin (ACTH) did not show any significant effect. It is concluded that the gonads of 12-day chick embryos have the capacity to respond to both gonadotropic and thyrotropic stimulation. This suggests that at the time when the hypothalamo-pituitary-thyroid axis begins to develop, the capacity of gonadal receptors to distinguish between gonadotropins and thyrotropin has not been established.
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    Development genes and evolution 190 (1981), S. 60-61 
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    Keywords: Cycloheximide ; Manduca sexta ; 20-hydroxy-ecdysone, insect tissue culture
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    Notes: Summary A clone (GV1) of the CHIManduca sexta cell line responds to 20-hydroxy-ecdysone by changing cellular shape from an epithelial-like form to an elongated fibroblast-like form. We have determined that this morphological response to hormone is prevented by treatment with cycloheximide. The inhibition of the elongation response by cycloheximide may relate to a requirement for the synthesis of specific proteins that play a role in the formation of cytoskeletal structure.
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    Development genes and evolution 190 (1981), S. 62-64 
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    Notes: Summary We have visualized segmentation in theDrosophila embryoniccentral nervous system (CNS) by staining for acetylcholinesterase activity. This technique was used to evaluate the effect of ligation on segments in the ventral CNS. When embryos were ligated prior to cellularization (60 min) fewer segmental ganglia developed in posterior fragments than when embryos were ligated at the blatoderm stage (3 h). This result is consistent with previous ligation experiments in which hypodermal segments were counted (Schubiger and Wood 1977). The number of ganglia scored exceeded the number of hypodermal segments scored especially after ligations at 60 min. Possible explanations for this difference are discussed.
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    Development genes and evolution 190 (1981), S. 83-86 
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    Keywords: Sea urchin ; Fibronectin ; Collagen ; Basement membrane
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    Notes: Summary Fibronectin, with a subunit molecular weight of 220,000 daltons, was isolated from the ovary of the sea urchin,Pseudocentrotus depressus, using affinity chromatography on heat-denatured mammalian collagen coupled to Sepharose 4B. The distribution of fibronectin in the sea urchin ovary was examined by indirect immunofluorescence using antifibronectin serum. The basement membrane and the connective tissues exhibited strong fluorescence. The fibronectin was localized closely together with collagen bundles in the sea urchin ovary. Biochemical and immunological examinations indicate that sea urchin fibronectin has similar properties as those of mammalian fibronectin.
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    Development genes and evolution 190 (1981), S. 67-72 
    ISSN: 1432-041X
    Keywords: Hydra ; Regeneration ; Bioassay ; Morphogen ; Statistical analysis
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    Notes: Summary Tentacle number in non-buddingHydra attenuata, randomly selected from mass culture varies 〈0.5 tentacles over a 3 month period. Replicate samples of untreated regenerates (n=50–60), however, show some variability in mean tentacle number regenerated (S x0.13–0.15). The variability is similar whether experiments are performed using randomly selected animals or animals with identical tentacle numbers. The variability is, further, not the result of profound differences in the time of tentacle initiation in individual animals. Addition of 10−5 M glutamate or a methanol extract to the assay medium results in both an earlier appearance of tentacles and in more tentacles being regenerated during early time periods. The mean tentacle number of methanol extract-treated animals is significantly higher than the mean tentacle number of either control or glutamate-treated animals at all time periods examined. The distribution of tentacle number classes among regenerates is normal in control and glutamate-treated animals but nonparametric in methanol extract-treated animals, making statistical analysis of the data using Student'st-test in-appropriate. The usefulness of the Mann WhitneyU and Kruskal-Wallis tests is discussed, as is the appropriateness of tentacle regeneration as an assay forhydra morphogens.
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    Development genes and evolution 190 (1981), S. 73-82 
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    Keywords: Polysomes ; Translation ; Microscopy, electron ; Sea urchin ; Embryology
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    Notes: Abstract Chromatin spreading techniques have been applied to the electron microscopic visualization of polysomes in sea urchin (Strongylocentrotus purpuratus) eggs and embryos. Polysomes of giant size are commonly found after the 8-cell stage. The largest seen, from an early gastrula, was 13.6 μm in length, carried 277 ribosomes, with a message calculated to contain 6.49×104 nucleotides and potentially to encoded 2.38×106 daltons of peptide. Polysomes are rare and very large ones absent from lysates of unfertilized eggs. Giant polysomes appear in 4- to 8-cell stages and are common in 16-cell stages and thereafter. They are of two forms: a compact form with no spacing between ribosomes characteristic of stages through early mesenchyme blastulae, and an extended form found only after late mesenchyme blastulae. Both have potential for massive informational content. Some of each type have ribosome-free tails at one end, as long as 733 Å in the compact forms, and 7,890 Å in the extended ones. Occasionally they have a single array of fibrous material increasing from one end of a polysome to the other, interpreted to be nascent peptide chains. Polysomes are not found after brief, mild exposure of lysates to RNase A, or from embryos treated with puromycin. Very large polysomes are present in lysates of blastulae exposed since fertilization to actinomycin D, cycloheximide, or cordycepin. They appear in parthenogenetically activated or fertilized enucleate merogones, but are absent from unactivated merogones, demonstrating that egg masked messages can generate them. A potential embryological significance of giant, potentially polycistronic polysomes is suggested.
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    Development genes and evolution 190 (1981), S. 87-91 
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    Keywords: Transcription ; Ribosomal RNA ; Macronuclear development ; Tetrahymena ; Nucleoli
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    Notes: Summary Conjugation inTetrahymena, as in other ciliated protozoa is both a necessary tool for genetic studies and a potential model system in development. Conjugation is an ordered sequence of events which involves pair formation between two cells of different mating types followed by a precise sequence of nuclear events leading to the establishment of a new recombinant germinal nucleus (micronucleus) and then to the development of a new somatic nucleus (macronnucleus) from the germinal nucleus. The whole process takes about 20 h at 30°C and can be performed with large volumes of cells. The synthesis of ribosomal RNA during macronuclear development was studied in cultures of conjugatingTetrahymena thermophila by following the incorporation of3H-uridine into whole cells and purified ribosomal and pre-ribosomal RNA as well as by measuring bulk-RNA accumulation. In starving cultures and conjugating cultures refed with growth medium during late conjugation, some (background) ribosomal RNA synthesis was detectable 11–12 h after mixing the cells, which is the time when conjugating cells come apart but the macronnucleus is still developing. However, the major burst of rRNA accumulation occurred 13–18 h in refed conjugants. Observation of the conjugating cells by transmission electron microscopy showed that development of nucleoli took place in the macronuclear analagen concomitantly with the major burst of ribosomal RNA synthesis (13–18 h). A nucleolar organization similar to that found in vegetative cells was attained in the macronuclear anlagen 18 h after mixing of the cells.
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    Development genes and evolution 190 (1981), S. 92-96 
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    Keywords: Embryonic induction ; Lectin ; Con A-Sepharose
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    Notes: Summary Lectins were used as probes to investigate the mechanism of embryonic induction. Concanavalin (Con A) and gorse agglutinin out of 7 species of lectins tested were found to have strong neural-inducing effect on the presumptive ectoderm of newt gastrulae. Their effects were abolished by the addition of α-methyl-D-mannoside and α-L-fucose, respectively. Succinyl-Con A had a weak inducing activity in comparison to Con A. Autoradiography of3H-Con A-treated explants revealed that Con A bound to the inner surface, but not to the outer surface of ectoderm and was successively incorporated into cytoplasm.3H-Thymidine incorporation was lower in the first half and higher in the second half of the 60 h cultivation period in Con A-treated explants as compared to controls. Con A-Sepharose had a strong inductive effect. This suggests that neural induction is caused through Con A binding to the plasma membrane, but not through incorporation into the cytoplasm of the ectoderm cells.
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  • 71
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    Keywords: Xenopus laevis ; Poly(A)+ nuclear RNA ; cDNA cloning ; Stage specificity
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    Notes: Summary Nuclear poly(A)+ RNA was isolated from gastrula and early tadpole stages ofXenopus laevis, transcribed into cDNA and integrated as double stranded cDNA by the G-C joining method into the Pst cleavage site of plasmid pBR 322. After cloning inE. coli strain HB 101 the clone libraries were hybridized to32P labelled cDNA derived from nuclear poly(A)+ RNA of the two different developmental stages. About 20% of the clones gave a positive hybridization signal thus representing RNA molecules of high and medium abundance. From these clones, some individual clones were identified containing sequences which are not present at the oocyte and gastrula stages but which are transcribed at the early tadpole stage of embryonic development.
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    Development genes and evolution 190 (1981), S. 111-117 
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    Keywords: Polyribosomes ; Poly(A) ; Cordycepin ; Echinoids
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    Notes: Summary The pattern of appearance of ribosomes, newly synthesized mRNA, and poly(A)-containing mRNA in polyribosomes has been examined in sand dollar embryos. From early blastula until shortly before hatching small polyribosomes engaged in histone synthesis predominate. At the time of hatching, when the rate of cell increase is maximal, the proportion of poly(A)-containing RNA in polyribosomes is low. After hatching a new class of large polyribosomes appears and the amount of poly(A)-containing polyribosomal RNA increases. Cordycepin, an inhibitor of RNA adenylylation, prevents the appearance of the large polyribosomes after hatching as well as the increase in poly(A)-containing polyribosomal RNA.
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    Development genes and evolution 190 (1981), S. 103-110 
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    Keywords: Xenopus embryo ; Polysomal mobilization ; Transport
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    Notes: Summary The mobilization of newly synthesized 18S and 28S rRNAs, 4S RNA and poly(A)+ RNA into polysomes was studied in isolated cells ofXenopus laevis embryos between cleavage and neurula stages. Throughout these stages, 4S RNA and poly(A)+ RNA were mobilized immediately following their appearance in the cytoplasm. 18S rRNA however, stayed in the ribosomal subunit fraction for about 30 min until the 28S rRNA appeared, when the two rRNAs were mobilized together at an equimolar ratio. This mobilization, at a 1:1 molar ratio, appeared to be realized at initiation monome formation. Thus, the efficiency of the mobilization of two newly synthesized rRNAs, shortly after their arrival at the cytoplasm, differed considerably but difference disappeared once steady state was reached. The contribution of newly synthesized 18S and 28S rRNAs to polysomes remains small throughout early development. around 3% of newly synthesized 4S RNA is polysomal which is the same distribution observed for unlabeled 4S RNA. Less than 10% of the newly synthesized cytoplasmic poly(A)+ RNA was mobilized into polysomes during cleavage, but in later stages the proportion increased to around 20%–25%. These results show that newly synthesized RNAs are utilized for protein synthesis at characteristic rates soon after they are synthesized during early embryonic development. On the basis of the data presented here and elsewhere we discuss quantitative aspects of the utilization of newly synthesized and maternal RNAs during early embryogenesis.
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    Development genes and evolution 190 (1981), S. 118-122 
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    Keywords: Drosophila ; Aggregation ; Lectins ; Cell surface ; Embryo-derived cell line
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    Notes: Summary In this paper we describe the aggregation of cells from embryo-derived cell lines ofDrosophila, measured by examining the ability of single cells to adhere to one another when suspended in culture medium and swirled on a rotary shaker. Using this method we demonstrated the presence of receptors for Concanavalin A, soybean agglutinin, and possibly wheat germ agglutinin on the surface of Schneider's line-2 cells. Our work provides basic descriptive and background information for further studies onDrosophila cells, including those isolated from imaginal discs.
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    Development genes and evolution 190 (1981), S. 123-125 
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    Keywords: Embryogenesis ; Cleavage ; Polarity ; Hydrozoan
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    Notes: Summary When the first cleavage of the hydrozoan egg is reversibly suppressed, two cleavage furrows frequently form simultaneously at the time of the second cleavage. If these two cleavage initiation sites are far enough apart, each one specifies a site of gastrulation, and the embryo that forms develops into a two tailed planula larva. When two tailed planulae are induced to metamorphose, they form a polyp with two stalks and hydranths.
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    Development genes and evolution 190 (1981), S. 132-138 
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    Keywords: Maternal effect mutant ; Homeotic-mutants ; Pattern formation ; Drosophila
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    Notes: Summary The temperature sensitive mutationfs(l)h is characterized at the restrictive temperature of 29°C by both a maternal effect responsible for the early embryonic lethality and pupal zygotic lethality. The two phenotypes are inseparable and map at a short deletion in the X chromosome (7Dl, 7D5-6). At semipermissive temperatures, hemizygous mutant females produce adults with morphological defects, such as organ deficiencies and homeotic transformations of haltere to wing and third leg to second leg. These defects depend on the maternal genotype and are governed by an early temperature sensitive period, which covers the end of oogenesis and the first hours of embryogenesis. Furthermore, this maternal effect mutation interacts with some dominant mutations of the bithorax system. These properties suggest thatfs(l)h is somehow involved in segmental determination.
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    Development genes and evolution 190 (1981), S. 127-131 
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    Keywords: Uteroglobin ; Radioimmunoassay ; Progesterone ; Osmotic minipumps ; Immunohistochemistry
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    Topics: Biology
    Notes: Summary This study was undertaken to determine whether the influx of progesterone into the uterine lumen of the rabbit, in the preimplantation period, is dependent onuteroglobin (UGL). Rabbits were ovariectomized and, three months later, treated with two defferent doses of progesterone. Purified UGL was injected into one uterine horn and, as a control,immunoglobulin G (IgG) was injected into the other. After four days, the animals were sacrificed their uteri flushed, and the progesterone content of the washes was determined by radioimmunoassay. Animals with the lower serum progesterone level (2.8 ng/ml) had a significantly different uterine horn progesterone content. The hormone accumulation in the horn containing UGL was 2.3 to 7.5 times higher than in the horn containing IgG. Animals with a higher serum progesterone level (7.2 ng/ml) showed no differences. The hormone content was equally high in both horns, presumably due to the synthesis of endogenous UGL being reactivated by the hormone treatment. The validity of these experiments as models for the events during early pregnancy and the physiological role of progesterone available inside the uterus are discussed.
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  • 78
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    Development genes and evolution 190 (1981), S. 139-142 
    ISSN: 1432-041X
    Keywords: Divalent cations ; Chick ; Embryonic cell adhesion
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    Topics: Biology
    Notes: Summary Cells from the extraembryonic endoderm of the gastrulating chick embryo adhere to one another in the absence of divalent cations. The addition of Mg2+ ions to the medium has no effect on the aggregation kinetics but the addition of Ca2+ ions increases the number of cells which aggregate and also stabilizes adhesion. Some aggregation also occurs when cells are suspended in saline devoid of Ca2+ and Mg2+ ions and supplemented with EGTA, a Ca2+ ion complexing agent, but adhesion is not stabilized. Shear sensitive and shear resistant bonds form in Ca-containing as well as in EGTA-containing saline. These results suggest that extraembryonic endoderm cells have Ca2+ indepedent and Ca2+ dependent mechanisms of adhesion.
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  • 79
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    Development genes and evolution 190 (1981), S. 143-149 
    ISSN: 1432-041X
    Keywords: MarineCnidaria ; Temperature Effect ; Dissociation ; Maceration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The effect of increased temperature on the tissue integrity of polyps and medusae ofPodocoryne carnea is described. Animals exposed for 10 to 20 min to a temperature of 35°C are easily dissociated into single cells. These dissociated cells round up, form reaggregates and, depending on their origin, regenerate polyp or medusa structures. However, as the exposure time is increased, the dissociated cells gradually lose the ability to reaggregate or to regenerate defined structures. At incubation times exceeding 50 min, the tissue separates into single cells which retain their normalin vivo shapes but which do not form reaggregates. These are termed macerated cells. The ultrastructure and protein profile of macerated cells demonstrate no major changes from those of untreated cells. Both the dissociation and maceration methods are applicable to other cnidarian species for developmental, histological and biochemical studies.
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  • 80
    ISSN: 1432-041X
    Keywords: Cytoskeleton ; Manduca sexta ; Insect cell cultures ; Clones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The embryonicManduca sexta cell line, MRRL-CH1 was cloned by dilution and single cell plating into conditioned medium, resulting in 6 cell clones with differing responses to the insect steroid hormone, 20-hydroxy-ecdysone. One of these clones, designated GV1, was studied with respect to cytoskeletal elements. Electron microscopic examination revealed that the microtubule networks became more extensive and organized increasingly parallel following exposure to the insect hormone 20-hydroxy-ecdysone, while inhibitors of microtubules were found to reverse the elongation response in the cells within 2.5 h. Agents affecting microfilaments (cytochalasins B and D) did not specifically alter the elongation response, but treatment with these agents did reveal increased cellular junctions as shown by increased cell aggregate size in hormone-treated cultures exposed to the cytochalasins.
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  • 81
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    Development genes and evolution 190 (1981), S. 197-207 
    ISSN: 1432-041X
    Keywords: Oocyte nuclear proteins ; Embryogenesis ; Monoclonal antibodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A library of hybridoma cell lines has been established which produce monoclonal antibodies against antigens from the germinal vesicle ofXenopus laevis oocytes. Many of the antigens are also found in the nuclei ofXenopus embryonic cells in culture. The fate of two of these antigens during embryogenesis was traced by immunofluorescence on embryo and tadpole sections. Early in development these antigens appear to be evenly distributed in the nuclei of all cells. In later stages they gradually disappear from most embryonic structures but are strongly accumulated in the nuclei of some specific cell types and organs.
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  • 82
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    Insectes sociaux 28 (1981), S. 27-31 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Nous décrivons dans cet article une forme aberrante deMyrmica scabrinodis Nylander. Cet individu a les scapes antennaires tronqués, présente une tendance à la formation de lobes sous le pétiole et le post-pétiole et à la réduction de l'éperon du tibia. La signification de ces anomalies est discutée dans le cadre de l'évolution des parasites sociaux.
    Notes: Summary An aberrant specimen ofMyrmica scabrinodis Nylander is described. The specimen has truncated antennal scapes, a tendency towards lobes beneath the petiole and post-peiole and reduced ibial spurs. The significance of the aberrations is discussed in terms of the evolution of social parasites.
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  • 83
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    Description / Table of Contents: Resume De nouvelles colonies du termites champignonisteMicrotermes sp. cf.usambaricus (Macrotermitinæ) ont été élevées avec succès en laboratoire jusqu'au stade de l'établissement d'une meule à champignons viable. La première meule est «ensemencée» avec leTermitomyces par la femelle reproductrice, qui a ingéré des spores asexuées (conidies) de la meule avant de quitter le nid parental. Ces conidies survivent dans le tube digestif jusqu'au moment où la première meule à champignons est construite, 10–11 semaines après la fondation de la colonie. La meule est entièrement faite de matières fécales et les observations préliminaires semblent indiquer que 5 semaines de digestion par le champignon sont nécessaires avant que la meule soit consommée par lesMicrotermes ouvriers. Chez les Macrotermitinæ, l'aptitude des colonies nouvellement fondées à produire une meule à champignons viable n'a été mise en évidence que chez le genreMicrotermes et chez une seule espèce du genreMacrotermes. Dans les deux cas, les reproducteurs transportent les spores du champignon dans leur tube digestif. Cette adaptation très évoluée à la symbiose fongique a de toute évidence joué un rôle important dans la large répartition et l'abondance du genreMicrotermes.
    Notes: Summary Incipient colonies of the fungus-growing termiteMicrotermes sp. nr.usambaricus (Macrotermitinæ) have been successfully cultured in the laboratory up to the stage where a viable fungus comb was established. The primordial fungus comb is inoculated with fungusTermitomyces by the female reproductive which ingests asexual spores (conidia) from the comb before leaving the parental nest. These conidia survive in the digestive tube until, 10–11 weeks after colony foundation, the first new fungus comb is built. The comb is built entirely of fæcal material and appears from these preliminary observations to require 5 weeks digestive action by the fungus before it is re-consumed by theMicrotermes workers. Within the Macrotermitinæ the ability of incipient colonies to produce a viable fungus comb has been demonstrated only in the genusMicrotermes and a single species of the genusMacrotermes. In both cases the reproductives transport the fungal spores in their digestive tube. This highly evolved adaptation to the fungal symbiosis has clearly played an important part in establishing the wide distribution and abundance of the genusMicrotermes.
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  • 84
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    Insectes sociaux 28 (1981), S. 13-26 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung In jeweils 150 Beobachtungsstunden wurde das Verhalten vonPolistes metricus unter zwei verschiedenen Bedingungen beobachtet: erstens imk Freiland an Nestern mit mehreren Nestgründerinnen vor dem Schlüpfen der Arbeiterbrut, und zweitens im Labor an Nestern einer einzelnen Gründerin nach dem Schlüpfen der Arbeiterinnen. Dabei konnten drei Arten von oszillierenden Bewegungen unterschieden werden, von denen zwei in diesem Bericht analysiert werden. Die eine ist das “Schwänzeln”: während das Weibchen über die Brutzellen läuft, führt es langsame horizontale Schwänzelbewegungen mit dem Hinterleib aus, die gegen das Nest gerichtet sind. In Nestern mit mehreren Gründerinnen wird dieses Schwänzeln fast ausschliesslich von Königinnen durchgeführt, in den Nestern mit nur einer Gründerin zeigen es die Königinnen häufiger als die Arbeiterinnen. In den Nestern ohne Arbeiterinnen wird das Schwänzeln unabhängig von der Gegenwart anderer Gründerinnen ausgeführt, aber erst dann, wenn die Brut das dritte Larvenstadium erreicht hat. Reaktionen anderer Gründerinnen auf das Schwänzeln konnten nicht festgestellt werden. In den Laborkolonien, in denen schon Arbeiterinnen vorhanden sind, tritt das Schwänzeln umso häufiger auf, je mehr Larven des dritten Stadiums vorhanden sind und je mehr Beuteflüge die Arbeiterinnen unternehmen. Als zweite Verhaltensweise wird das «seitliche Trommeln» analysiert: dabei schlägt ein Weibchen durch schnelle, waagrechte Vibrationen seines ganzen Körpers gegen die Oberseite des Nestes und erzeugt einen kurzen, lauten Schallstoss. In den Freilandkolonien zeigten die Königinnen und die subdominanten Gründerinnen dieses Verhalten gleich häuftig. Die Weibchen reagieren untereinander oft sehr deutlich auf das trommeln, wobei Königinnen und subdominante Gründerinnen in unterschiedlicher Weise antworten. In den Kolonien mit Arbeiterinnen trommeln die Königinnen weit häufiger als die Arbeiterinnen, und sie trommeln umso öfter, je mehr Arbeiterinnen, adulte Weibchen und Larven die Kolonie enthält. Wir vermuten, dass das «Schwänzeln» hauptsächlich der Kommunikation zwischen Imagines und Larven dient, wohingegen das «Trommeln» an der Regelung der Rangordnung erwachsener Tiere beteiligt ist.
    Notes: Summary Field studies (150 h) on pre-emergence, multiple-foundress colonies and laboratory observations (150 h) on post-emergence, single-foundress colonies revealed three distinct types of oscillatory movements in adultPolistes metricus. Two of these are analysed in this report. “Abdominal wagging” is a slow, horizontal abdominal oscillation performed by a female against the nest as she walks over brood cells. It is almost exclusively performed by queens in pre-emergence, foundress associations and more often by queens than workers in post-emergence colonies. In pre-emergence colonies abdominal wagging is done independently of the presence of other foundresses and first appears in colonies when broods contain third instar larvæ. We recorded no responses by other foundresses to abdominal wagging. In post-emergence colonies the performance of abdominal wagging is significantly correlated with both numbers of third larval instars and prey trips by workers. “Lateral vibrations” consist of a female rapidly shaking her entire body in a horizontal plane against the top of the nest producing a short, loud burst of sound. Queens and subordinates exhibit this behavior equally often in early, pre-emergence colonies. Gynes frequently respond markedly to lateral vibrations by other foundresses with queens and subordinates exhibiting distinct responses. In post-emergence colonies queens laterally vibrate more often than workers and the number of vibrations by queens is highly correlated with the number of workers, adult females and larvæ at the colony. We suggest that abdominal wagging principally functions in adult-brood interactions and lateral vibrations are involved in adult dominance communication.
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  • 85
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Summary A laboratory nest ofAcromyrmex octospinosus (Reich) is shown to respond to an artificially applied magnetic field by avoidance reactions. This is most clearly seen in the marked, and repeatable movement of brood by workers, which becomes more obvious as the magnetic field increases. Sensitivity to the magnetic flux appears high.
    Notes: Resume Un nid artificiel de fourmi-manioc (Acromyrmex octospinosus Reich) subissant l'influence d'un aimant permanent, produit une réponse durable et répétable d'évitement: le déplacement du couvain par les ouvrières. Une série d'essais préliminaires montre que cette réaction est d'autant plus nette que le champ magnétique est grand. La sensibilité de la société d'attines au flux magnétique semble relativement élevée.
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  • 86
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    Topics: Biology
    Description / Table of Contents: Resume Les effets dûs à la taille du groupe, à l'époque de l'année et aux proportions initiales de soldats ont été explorés dans des groupes expérimentaux deReticulitermes flavipes (Kollar) et deReticulitermes virginicus (Banks). On a élevé des groupes en laboratoire pedant 12 semaines. Les petits groupes (de 500 à 1000 ouvriers) ont produit un plus faible pourcentage de soldats que les grands groupes (de 1500 à 2000 ouvriers). Le nombre de soldats produits dans un groupe est hautement corrélé au nombre total de termites qui survivent. Le pourcentage moyen observé dans tous les groupes a été de 1,75 pour les 2 espèces étudiées. La production de soldats chezReticulitermes flavipes a été la plus élevée dans les colonies prélevées en avril (2%) et la plus faible dans celles prélevées en octobre (0,38%). Les observations bimensuelles des augmentations et des baisses de production de soldats montrent qu'il y a un cycle saisonnier du potentiel de développement. La présence de soldats dans les groupes inhibe la production de nouveaux soldats. Un pourcentage anormalement élevé de soldats n'a pas provoqué l'élimination massive de soldats. De plus, la surcharge des groupes en soldats (plus de 1,75%) n'a pas affecté de façon nuisible la survie du groupe.
    Notes: Summary The effects of group size, time of year, and initial proportions of soldiers were explored in experimental groups ofReticulitermes flavipes (Kollar) andR. virginicus (Banks). Groups were held in the laboratory for 12 weeks. Small groups (500 to 1000 workers) produced a smaller percentage of soldiers than did larger groups (1500 to 2500 workers). The number of soldiers produced in a group is highly correlated with the total number of termites surviving. The average percentage produced for all group sizes was 1.75 for both species. Production of soldiers inR. flavipes was highest in colonies collected in April (2.0%) and lowest in those collected in October (0.38%). Bimonthly observations of increases and decreases in soldier production indicate a seasonal cycle in developmental potential. Presence of soldiers in groups inhibited the production of new soldiers. An abnormally high percentage of soldiers did not precipitate extensive elimination of soldiers. In addition, overloading groups with soldiers (more than 1.75%) did not adversely affect group survival.
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    Insectes sociaux 28 (1981), S. 67-70 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary Doronomyrmex pacis Kutter,Epimyrma stumperi Kutter andEpimyrma goesswaldi Menozzi could be collected for the first time in France. The localities are near Saint-Jean de Maurienne (D. p., E. st.) and Saint-André near Modane (D. p., E. goe.) in the Maurienne, Haute-Savoie. The known area of these 3 species is considerably enlarged by our findings. In the same area we also collectedHarpagoxenus sublaevis, Strongylognathus alpinus, Anergates atratulus andBothriomyrmex menozzii.
    Notes: Resume Les espècesDoronomyrmex pacis Kutter,Epimyrma stumperi Kutter etEpimyrma goesswaldi Menozzi ont été capturées pour la première fois en France. Les localités se trouvent dans la Maurienne, Haute-Savoie, près de Saint-Jean-de-Mauriene (D. p., E. st.) et à Saint-André près de Modane (D. p., E. goe.). L'aire de répartition de ces trois espèces est considérablement élargie par ces découvertes. On a récolté aussi dans cette régionHarpagoxenus sublaevis, Strongylognathus alpinus, Anergates atratulus etBothriomyrmex menozzii.
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  • 88
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Summary We report the result of 34 experiments in which ants could use visual and chemical cues to orientate after foraging on honey. In some cases, all ants used chemical cues; in other cases most ants used visual cues as well as chemical cues. However, we never observed the case that all ants used only visual cues. Analysis of the data by correspondance analysis (=reciprocal averaging) shows that the use of chemical or visual cues closely depends on parameters which changed from one experiment to another throughout the year. In the majority of cases, all ants used chemical cues when experiments were carried out in spring, in the morning, after a preliminary short period of feeding and under certain climatic conditions. A greater number of ants used visual cues in summer. The study of parameters which influence the orientation in relation to chemical or visual cues tends to confirm the hypothesis that individual experimence is involved in selection of visual cues rather than of chemical cues. When recruited ants were naive they find the food place by following the chemical trail which was laid down by experienced workers were foraging on that area. Then recruited ants progressively learn to use visual cues. But as the chemical trail would still be laid down, foragers could use chemical cues as well as visual cues.
    Notes: Resume La répétition de expériences de choix entre repères visuels et repères chimiques nous ont permis de constater que l'utilisation de ces repères orientationnels est variable: dans certains cas, toutes les fourmis s'orientent par rapport aux repères chimiques, dans d'autres cas le nombre de fourmis qui s'orientent par rapport aux repères visuels est supérieure, identique ou inférieure au nombre de fourmis qui s'orientent par rapport aux repères chimiques. Nous n'avons jamais obtenu le cas dans lequel toutes les fourmis s'orientent par rapport aux repères visuels. L'analyse des données par la méthode de l'analyse factorielle des correspondances montre que l'utilisation des repères visuels et chimiques dépend étroitement de certains paramètres qui ont varié au cours des expériences successives. Il ressort de cette analyse que dans la majorité des cas, toutes les fourmis s'orientent par rapport aux repères chimiques lorsque les expériences ont lieu au printemps, le matin, après une période de nourrissage préliminaire courte et sous certaines conditions climatiques. D'autre part, ce serait en été qu'un grand nombre d'entre elles s'orientent par rapport aux repères visuels. Les paramètres saison, heure de la journée, durée du nourrissage préliminaire apportent des éléments positifs à l'hypothèse suivant laquelle l'utilisation des repères visuels et chimiques est fonction de l'expérience individuelle des fourmis. Dans un premier temps, les ouvrières recrutées et donc «inexpérimentées» sont guidées vers la source de nourriture par la piste chimique déposée sur le substrat par les ouvrières qui ont découvert la source de nourriture par hasard. Lors des premiers voyages, recruteuses et recrutées guidées par les repères chimiques apprennent à s'orienter sur les repères visuels. Dans un deuxième temps, la piste chimique n'a qu'une influence minime dans l'orientation de ces mêmes fourmis; elles se dirigent alors par rapport à des repères visuels. En revanche, la piste qui continue à être déposée permet le guidage vers la source de nourriture de nouvelles ouvrières «inexpérimentées». Le fait que les ouvrières expérimentées restent sensibles à la présence d'une piste chimique déposée sur le trajet qu'elles empruntent habituellement rend possible le retour aux repères chimiques en tant que repères orientationnels.
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    Insectes sociaux 28 (1981), S. 71-86 
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung BeiMacrotermes sabhyalinus wurden Haemolymph-Proteine und-Esterasen, beiZootermopsis angusticolhe Haemolymph-Proteine diskelektrophoretisch untersucht. Die Bandenmuster waren beiM. subhyalinus kastenspezifisch, beiZ. angusticollis dagegen einheitlich bei allen Kasten beider Geschlechter. BeiM. subhyalinus wurden zudem Unterschiede in der Aktivität von Esterasen, speziell Carboxylesterasen, sowie in der Bindungskapazität der Haemolymphe für Juvenilhormon festgestellt. Diese Resultate werden in Beziehung gesetzt zu den aktuellen Vorstellungen über Kastendetermination bei niederen und höheren Terrniten.
    Notes: Summary Haemolymph proteins and esterases ofMacrotermes subhyalinus and haemolymph proteins ofZootermopsis angusticollis have been analyzed electrophoretically. The patterns were caste specific inM. subhyalinus, but uniform for all castes and sexes inZ. angusticollis. InM. subhyalinus the activities of esterases, especially that of carboxylesterases, and the haemolymph binding capacity for juvenile hormone differend between castes. The results are discussed in relation to the present knowledge about caste determination in lower and higher termites.
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    Insectes sociaux 28 (1981), S. 105-116 
    ISSN: 1420-9098
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    Topics: Biology
    Description / Table of Contents: Resume Dans un rassemblement de nids de l'HalictinaeAgapostemon virescens, une espèce avec une seule génération par année, dans l'Etat de New York aux Etats-Unis, 58% des femelles ont changé de nid pendant leur vie adulte. Le gardiennage continuel protégeait les nids communaux contre l'abeille cleptoparasiteNomada articulata, qui attaquait avec succès les nids des femelles solitaires. Toutes les femelles jouaient le rôle de pondeuse et de pourvoyeuse de pollen, au moins occasionnellement. A la fin de l'été, quelques-uns des occupants du nid se spécialisent en gardiennes et d'autres en pourvoyeuses.
    Notes: Summary In a nest aggregation of the univoltine sweat beeAgapostemon virescens in New York State, U.S.A., 58% of the adult females switched nests during their adult lives. Continuous guarding protected communal nests against the cleptoparasitic beeNomada articulata which successfully attacked nests occupied by solitary females. All females were egg layers and foraged for pollen at least occasionally. At the end of the foraging season, some nestmates usually acted as guards while others usually foraged.
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  • 91
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung An Laborkolonien vonPolistes metricus wurde die Arbeitsteilung der Arbeiterinnen bei der Nahrungssuche studiert. Die Sammelaktivität der einzelnen Individuen hing stark von der Sammelaktivität Nesgenossen ab. In der Regel sammelte hauptsächlich die älteste Arbeiterin. Andere Arbeiterinnen, gleich welchen Alters, unternahmen vergleichsweise wenige Sammelflüge, solange eine aktive Sammlerin vorhanden war. Wenn ältere, aktive Sammlerinnen aus der Kolonie entfernt wurden oder mit zunehmendem Alter in ihrer Aktivität nachließen, so flogen die vorher vergleichsweise wenig aktiven Arbeiterinnen öfter. Ein Anstieg ihrer Sammeltätigkeit war auch dann zu verzeichnen, wenn sich der Nahrungsbedarf der Kolonie erhöhte (was man an einer deutlichen Zunahme der Larvenzahl ablesen konnte). Eine zeitliche Anderung der Aufgabenteilung beim Sammeln wurde nicht beobachtet. Der einzige Hinweis auf eine dauerhafte Spezialisierung betraf das Sammeln von Papier. Während alle Arbeiterinnen Wasser, Honig und tierische Beute eintrugen, war das Sammeln von Papier fast ausschliesslich den ältesten Arbeiterinnen vorbehalten.
    Notes: Summary Division of labor in foraging activities of workers was studied in laboratory colonies ofPolistes metricus. Individual foraging activity was strongly affected by the foraging activities of nestmates. Usually the oldest worker of a colony became the principal forager. Other workers, in the presence of an active forager, did relatively little foraging regardless of age. Relatively inactive workers showed increased foraging rates when the older, active foragers were either removed or became less active with age, or when colony needs were greater (as evidenced by a marked rise in larval numbers). There was no temporal change in distribution of foraging tasks. The only indication of permanent task specialization was for paper collecting. All workers foraged for prey, water and honey but collection of paper was confined almost exclusively to the oldest workers of the colony.
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  • 92
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    Topics: Biology
    Description / Table of Contents: Resume La distribution de protéines du jaune d'œuf sous trois présentations différentes, d'hémoglobine bovine liquide, d'huile de soja, de miel et enfin d'eau a été étudiée au laboratoire dans des colonies de la «fourmi de feu» (Solenopsis invicta Buren). L'albumine et l'hémoglobine ont été marquées avec de l'iode radio-actif (125I) à haut niveau d'activité spécifique (10–15 μCi/μg) puis ajoutées à la nourriture protéique. L'iode radio-actif a été ajouté aux autres aliments comme indicateur libre. Chaque aliment a été offert de manière continue pendant une période de 48 heures alors que des échantillons étaient analysés au bout de 1, 2, 3, 6, 12, 24 et 48 heures. Dans le cas du mélange albumine marquée/jaune d'œuf en poudre, les larves retiennent 80% de la nourriture et les ouvrières 20%. Dans le cas de protéines liquides, la proportion est de 45–55% pour les larves et 55–45% pour les ouvrières. Le miel et l'huile de soja sont conservés 12–24 heures par les ouvrières avant d'atteindre les larves. Dans le cas du miel, les larves retiennent en tout 40% et les ouvrières 60% alors qu'avec l'huile de soja les proportions sont de 30% pour les larves et 70% pour les ouvrières. De plus la distribution des aliments ainsi que leur consommation moyenne (exprimée en microgrammes ou microlitres) ont été déterminées.
    Notes: Summary The distribution of three forms of egg yolk protein, liquid bovine hemoglobin, soybean oil, honey, and water was studied in laboratory colonies of the imported fire antSolenopsis invicta Buren. Albumin and hemoglobin were radiolabelled with125Iodine to a high specific activity (10–15 μCi/μg) and added to protein foods.125I was mixed with the other foods as a free label. Each food was presented continuously over a 48 hour period and samples were taken at 1, 2, 3, 6, 12, 24, and 48 hours. The ration of distribution of125I-albumin in powdered egg yolk was 80% in the larvae and 20% in the workers. For proteins in liquid form it remained at 45–55% in the larvae and 55–45% in the workers. The honey and soybean oil were retained by the workers for 12–24 hours before reaching the larvae. The overall ratio of distribution was 40% in the larvae and 60% in the workers with honey and 30% in the larvae and 70% in the workers with soybean oil. The distribution of food and average cumulative consumption in micrograms or microliters were determined.
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    Insectes sociaux 28 (1981), S. 117-128 
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    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Arbeiterinnen der AmeiseSolenopsis invicta zeigen einen mäßigen Polymorphismus mit einer Variation der Kopfbreite von 0.45 mm bis 1.50 mm. Arbeiterinnen bis 0.80 mm wurden als klein, bis 1.00 als mittel und bis 1.50 als groß bezeichnet. Erwachsene Kolonien bestehen durchschnittlich aus 45% kleinen 42% mittleren und 16% großen Ameisen. Königinnen, die im Labor Kolonien gründen, produzieren nur “Pygmäen» Arbeiterinnen in der ersten Brut, die kleinsten Arbeiterinnen im Leben der Kolonie. Wenn die Kolonien heranwachsen, erzeugen sie größere Ameisen, bis im Alter von 7 Monaten Kopfbreiten zwischen 0.50 und 1.50 mm erreicht werden. Die Größenverteilung waren dann stark asymmetrisch, so daß die Kolonien aus 88% kleinen, 11% mittleren und 1% großen Arbeiterinnen bestanden. Frischbegattete Königinnen wurden im Labor von kleinen (500 Ameisen), mittleren (2000) oder großen (15,000) Kolonien mit Arbeiterinnen jeweils einer der drei verschiedenen Größenklassen adoptiert (9 Gruppen). Die Variation der Arbeiteringröße hatte keinen Effekt auf die Zahl oder Größe der produzierten Arbeiterpuppen. Andererseits waren die Zahl und Kopfbreite der Puppen in den ersten Bruten im Durchschnitt 1) größer als die von neu gegründeten Kolonien (Pygmäen-Arbeiterinnen fehlten), und 2) positiv mit des Koloniegrösse korreliert. Puppenzahl und Größe wuchsen beide im Verlauf des 4-monatigen Experiments an, obwohl die Zahl der Arbeiterinnen konstant gehalten wurde.
    Notes: Summary Solenopsis invicta workers display a slight polymorphism over a size range of head widths from 0.45 mm to 1.50 mm. Those measuring through 0.80 mm were designated small, through 1.00 mm, medium, and through 1.50 mm, large. Mature field colonies have small, medium, and large worker ratios of 45%, 42%, and 16% respectively. Queens founding colonies in the lab produced initial broods of minim workers, the smallest and only individuals a queen rears by herself. As colony populations grew, size classes of larger ants accumulated until after 7 months, ants with head widths ranging in size from 0.50–1.50 mm were produced. Size class distributions were skewed such that small, medium, and large ants made up 88%, 11% and 1% of the population, respectively. Newly mated queens were adopted into small (500 ants), medium (2000 ants), and large (15,000 ants) experimental colonies of field ants of three ranges of worker size variation (9 treatments). No effect of worker size variation on pupal production or pupal size was detected. The mean numbers and mean head width of pupae in their initial broods were: (1) greater than those of newly founded colonies (minims were lacking); and, (2) correlated to experimental colony size. Both pupal numbers and mean pupal size increased throughout the 4-month experiment even though worker number was kept constant.
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    Insectes sociaux 28 (1981), S. 161-166 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume 1. Contrairement aux larves femelles, les larves mâles du troisième stade ne sont pas attaquées par les ouvrières, lorsque les reines sont présentes. 2. Bien qu'elles soient sous-alimentées et qu'elles deviennent moins grosses en présence des reines qu'en l'absence de celles-ci, elles ne montrent pas un taux de mortalité plus élevé. 3. En effet, le facteur responsable du contrôle du nombre de mâles réside dans le contrôle de l'ovogenèse des ouvrières par les reines et leurs œufs.
    Notes: Summary 1. Unlike female larvae, male larvae are not attacked by workers under queen influence during spring growth in the third instar. 2. Though they are underfed in these circumstances and mature at a smaller size, than they would if queens were absent, there is no evidence that they die, at least in the third larval instar. 3. It follows that control over male number, but not size, relies on the oogenetic switch from reproductive to trophic, that laying queens and their egg masses effect.
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    Insectes sociaux 28 (1981), S. 167-181 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary We have studied histological modifications in neurosecretory organs in relation to the genital activity. In winter, ovocytes do not mature and turn intocorpora lutea. The gathering of neurosecretory products is noticed inpars intercerebralis and incorpora cardiaca. In spring, neurosecretory products leave firstcorpora cardiaca and thenpars inter-cerebralis. Corpora allata come to activity: the nucleoplasmic ratio is increasing, from 4 to 6 nucleoles can be seen in each cell. Then the yolk is gathering in the ovocytes. During egg-laying, there is few or no neurosecretory products inpars intercerebralis and incorpora cardiaca. Corpora allata are active. At the end of summer, egg-laying ceases. We notice the gathering of neurosecretory products inpars intercerebralis and incorpora cardiaca. Incorpora allata, nucleoplasmic ratio is decreasing and the number of nucleoles too. The amount of neurosecretory products is in relation to the abundance of egg-laying, which increases each year after colony founding.
    Notes: Resume Etude des modifications histologiques de l'appareil neurosécréteur céphalique en fonction de l'activité de ponte. Pendant l'hiver, les ovaires produisent quelques ovocytes qui dégénèrent en corps jaunes. Les produits de la neurosécrétion de lapars intercerebralis s'accumulent sur place et dans lescorpora cardiaca. Au printemps, ces produits de neurosécrétion sont mobilisés et disparaissent d'abord descorpora cardiaca, ensuite de lapars intercerebralis. Lescorpora allata montrent des signes d'activité: augmentation du rapport nucléoplasmique, multiplication des nucléoles. Peu après, des ovocytes se chargent de vitellus. Pendant la ponte, il y a peu ou pas de produits de neurosécrétion dans lapars intercerebralis et dans lescorpora cardiaca; lescorpora allata sont actifs. En fin d'été, la ponte s'arrête progressivement: dans lescorpora allata, le rapport nucléoplasmique décroît, des nucléoles disparaissent. Des produits de neurosécrétion commencent à s'accumuler dans lapars intercerebralis, puis dans lescorpora cardiaca. La quantité de produits de neurosécrétion accumulée est en rapport avec l'abondance de la ponte, qui augmente d'année en année après la fondation de la société.
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    Insectes sociaux 28 (1981), S. 208-216 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Les nids de la GuêpeParischnogaster mellyi que nous avons étudiés étainent faits de longues et minces lnières de végétation morte suspendue. La structure du nid variait du rayon simple à des cellules dispersées le long de la lanière suspendue. La structure la plus fréquente était un nid étiré avec un minimum de parois communes aux cellules. Dans un nid suspendu sur une grande langueur, la première cellule était éloignée des deux extrémités. Ensuite, l'agrandissement s'était fait au dessus et au dessous de cette première cellule. L'avantage du nid long et étroit pourrait être que le nid est ainsi caché des prédateurs qui chassent à vue. Les matériaux de construction sont des cuticules de plantes et des tiges de bois. Ils se présentent sous forme de mietters et de paillettes. Ils sont donc fragiles et non appropriés à la construction de grands nids. Il est possible que le limites physiques des matériaux de construction utilises par les Guêpes Sténograstrines aient pu empêcher l'évolution de colonies de grandes dimensions.
    Notes: Summary Nests ofParischnogaster mellyi were built upon long thin strands of hanging dead vegetation. The nest design varied from a single comb structure to cells spread along the length of the suspension. The preferred nest design was found to be an elongate nest with minimal cell was sharing. On a long nest suspension the first cell was placed remote from either end. Subsequent nest expansion extended both above and below this first cell. It is suggested that advantage of a long, narrow nest may be concealment from visual hunting predators. Nest material is composed of plant cuticle as well as woody stems. It has a composition of fine crumbs and flakes; in consequence it is fragile and unsuited to the large nests. It is suggested that the physical limitations of the nest material in stenogastrinæ may have inhibited the evolution of large colony sizes.
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    Insectes sociaux 28 (1981), S. 182-190 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Dendromyrmex chartifex undD. fabricii sind Weberameisen: Die erwachsenen Larven dieser Formicinen-Arten fügen den arborealen Kartonnestern Seide zu. Dieses Seidematerial verstärkt die aus pflanzlichen Teilchen bestehenden Wände der Nestkammern, die von Arbeitern gebaut werden. Das kommunale Seide-Spinnen vonDendromyrmex ist die bis jetzt primitivste Form dieses Verhaltens und könnte die erste Stufe in der Evolution des Webens bei Ameisen darstellen. Nicht die Arbeiter, welche die Larven mit den mandibeln halten, sondern die Larven machen die seitlich gerichteten Spinnbewegungen. Dieses Verhalten unterscheidet sich vom konventionellen Kokon-Spinnen nur in der Orientierung der Bewegungen in Bezug zum Körper. Oft produzieren sogar die Larven Seide zum Nestbau, ohne dabei von den Arbeitern gehalten zu werden. Männchenlarven und Arbeiterlarven zeigen kommunales Spinnverhalten; ob beide die gleiche Menge Seide per Individuum produzieren muss noch festgestellt werden. Weitere Beobachtungen im Freiland und Laboratorium zur Biologie vonDendromyrmex werden berichtet: Die Kolonien sind polydom; die Arbeiter furagieren nachts und nehmen eine Vielfalt von Insekten als Futterbeute an. Die Arbeiter vonD. chartifex haben auffallende Augenflecken und verhalten sich als ob sie Polybiinen-Wespen nachahmten. Es wird vermutet, dass es sich hier um eine Batessche Mimikry dieser stechenden Insekten handelt.
    Notes: Summary Dendromyrmex chartifex andD. fabricii are weaver ants: the mature larvae of these formicine species add silk to the arboreal carton nests. This material strengthens the layers of vegetable fibers, which form the bulk of the nests and are contributed by the workers. The communal silk spinning is the most primitive yet discovered and may represent the first stage in the evolution of weaving. The larvae, rather than the workers that hold them in their mandibles, make the lateral weaving movements, and their behavior differs from conventional cocoon spinning only in the orientation of the movements relative to the body. Moreover, larvae often contribute silk in this manner even when unattended by workers. Both male and worker-destined larvae spin communally; whether they contribute equal quantities per capita remains to be determined. Other information on the natural history ofDendromyrmex based on field and laboratory studies is reported: the colonies are polydomous; the workers forage nocturnally and accept a wide variety of insect prey. The workers ofD. chartifex have unusual genal eyespots and behave in such a way as to resemble polybiine wasps, and it is suggested that they are in fact Batesian mimics of these stinging insects.
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    Insectes sociaux 28 (1981), S. 263-278 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Dans ce travail, on se propose d'établir à quel moment et par l'intermédiaire de quelle caste femelle les mâles apparaissent chezMyrmica rubra L. Chez cette espèce, les œufs reproducteurs pondus par les ouvrières sont toujours mâles mais la présence des reines supprime normalement leur production. Les conditions dans lesquelles les ouvrières produisent des œufs en présence des reines ont donc été étudiées en détail. - 1. Des fourmis adultes ont été nourries avec des colorants solubles dans les lipides afin de marquer les œufs; on peut ainsi étudier la production des ouvrières tant dans la nature qu'au laboratoire. Les résultats ainsi que les données issues d'échantillonnages suggèrent fortement que les ouvrières nouvellement nées sont les principales et peut-être même les seules pondeuses d'œufs mâles. - 2. Il y a une corrélation positive entre le poids sec des mâles produits dans de grands élevages artificiels et le nombre originel d'ouvrières contenues dans ces élevages; par contre il n'y a pas de relation entre ce même poids sec des mâles et le nombre de reines ou le ratio reines/ouvrières. - 3. Le prélèvement d'échantillons d'œufs dans la nature a montré que les œufs mâles sont pondus à la fin de l'été quand il y a beaucoup d'ouvrières nouvellement nées dans les nids. - 4. La dissection d'ouvrières prélevées dans la nature a montré que l'on trouve plus souvent des ovocytes chez les jeunes ouvrières que chez les plus âgées.
    Notes: Summary The aim of this work was to determine when and by which female caste the males are produced inMyrmica rubra L. In this species reproductive eggs laid by workers are in which workers produce eggs in the presence of queens were therefore investigated. - 1. Lipid dyes were fed to adult ants to mark their eggs in the field and laboratory in order to investigate worker egg production. The resulting data, along with those from sampling, strongly suggest newly-ecloding workers to be the primary, possibly sole, source of males. - 2. The dry weight of males produced in large artificial nests was positively correlated with the original number of workers which the nests contained, though not with the number of queens or the ratio of queens to workers. - 3. Egg sampling showed that male eggs were laid in late summer when there are many callow workers in the nests. - 4. Dissection of workers from field colonies showed that a higher proportion of callow and pale-coloured ants contain ova than do older ants.
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    Insectes sociaux 28 (1981), S. 279-296 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume Les sociétés deLasius sakagamii Yamauchi et Hayashida ont une organisation polycalique particulière, caractérisée par les faits suivants: 1) accouplements entre membres du même nid; 2) maintien des femelles nouvellement écloses dans le nid maternel, donc société polygyne; 3) comportement territorial peu développé; 4) reproduction des sociétés par bourgeonnement; 5) croissance de la société jusqu'à plusieurs millions d'ouvrières; 6) saturation des habitats préférés, et dominance locale. La comparaison avec d'autres espèces de Fourmis polycaliques montre que l'organisation polycalique de l'espèce étudiée est relativement peu différenciée et rudimentaire, et constitue un matériel favorable pour l'étude de l'évolution du système polycalique.
    Notes: Summary Sociobiological studies were made of the polygynic ant speciesLasius sakagamii Yamauchi et Hayashida. This species has a peculiar polydomous system characterized by 1) intranidal mating, 2) retention of newly emerged queens in the mother nest, resulting in a polygynic colony, 3) reduced territorial behavior, 4) colony multiplication by budding, 5) enlargement of colony size up to several millions of workers, 6) saturation and domination of preferred local habitat. Compared with that of other polydomous species, the polydomous system of this species may be considered relatively undifferentiated or rudimentary, offering valuable materials for the study of the evolution of polydomous systems.
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    Pure and applied geophysics 119 (1981), S. 1144-1156 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract This paper describes the deep seismic soundings performed in Romania. The technique of field works, the characteristics of the recorded waves and the main results obtained on the profiles is analysed. A brief description of the crustal structure that characterizes the different geotectonical units in Romania investigated by seismic surveys performed during a period longer than 10 years of activity is given.
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