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1.
The filtration rates of two species of eulamellibranchs (Dreissena polymorpha, Sphaerium corneum) were determined for 2-hour-intervals always over one day. The described pattern of activity of the filtration efficiency has two or three peaks. The single values vary up to the ratio of one to ten. Therefore calculations of filtration capacities based on single measurements are very in-accurate.
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2.
Last December marked the 20th anniversary of the Nobel Prize in Chemistry to Sidney Altman and Thomas Cech for their discovery of RNA catalysts in bacterial ribonuclease P (an enzyme catalyzing 5′ maturation of tRNAs) and a self-splicing rRNA of Tetrahymena, respectively. Coinciding with the publication of a treatise on RNase P,1 this review provides a historical narrative, a brief report on our current knowledge, and a discussion of some research prospects on RNase P.
the great thing about science is that you can actually solve a problem. You can take something which is confused, a mess, and not only find a solution, but prove it's the right one.”2
-Sydney Brenner
“In research the front line is almost always in a fog.”3
-Francis Crick
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3.
Zusammenfassung An Stichproben mehrerer Bantupopulationen aus Angola und Südafrika wurden Hautleistenbefunde untersucht, zusammen 1828 Normalpersonen. Unter diesen zeigten 26 ein- oder beidseitig eine rudimentäre Polydaktylie seitlich am V. Finger (1,42%).
Rudimentary polydactyly in Bantu-Negroes
Summary Samples of various bantu populations of Angola and South Africa were examined dactyloscopically, totalling 1828 normal individuals. Among those, 26 persons showed rudimentary polydactyly aside of the fifth finger on one or both hands (1.42%).
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4.
Zusammenfassung Die Fischfamilie der Cypriniden zeigt nach Chromosomenzahl und DNS-Gehalt/Zelle ein Diploid-Tetraploid-Verhältnis. Eine Duplikation der MDH-Isoenzyme läßt sich in der tetraploiden Gruppe nachweisen. Nur der tetraploide Cyprinus carpio hat ein Muster entsprechend der diploiden Gruppe.
Polyploidization in the fish family Cyprinidae Duplication of the gene loci for NAD-dependent malate dehydrogenase
Summary The fish family Cyprinidae can be classified into two groups, a diploid one and a tetraploid one, as shown by chromosome analysis and measurements of the DNA content per cell. Duplications of the MDH isoenzymes can be demonstrated in the tetraploid group with one exception: Cyprinus carpio reveals the diploid pattern.


Direktor: Prof. Dr. Dr. H. Ritter

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

5.
Summary During investigations on the migration of 120 individual White Storks by means of satellite tracking, four birds were tracked into their winter quarters several times, one bird on nine successive journeys. These storks did not exhibit strong winter-site fidelity, but instead occupied somewhat different winter quarters from one year to the next, probably depending on the food supply.
Langzeit Satelliten-Telemetrie beim Wei?storch gibt Hinweise auf variable Zug- und überwinterungsstrategien
Zusammenfassung Bisher konnten wir 120 Wei?st?rche auf ihrem Zug mit Hilfe der Satelliten-Telemetrie verfolgen, 4 V?gel mehrfach und einen auf neun aufeinander folgenden Wanderungen. Dabei zeichnet sich ab, dass Wei?st?rche im Gegensatz zu vielen anderen Afrikaziehern nur geringe Winterquartiertreue zeigen und im Laufe von Jahren in verschiedenen Gebieten überwintern, wahrscheinlich in Abh ?ngigkeit vom Nahrungsangebot.
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6.
Thielavia heterothallica spec. nov. is described as a heterothallic, thermophilic fungus with spherical, black, non-ostiolatecleistothecia; ellipsoidal, evanescent asci which contain eight one-celled ellipsoidal ascospores, darkening to deep brown to black, with one germ pore. The conidial state is Chrysosporium thermophilum (Apinis) von Klopotek.
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7.
Summary About the ecology of Juncus balticus Willd. in West-Island (Snaefellnes): this plant only grows between the bogs on the one hand and the saltmarshes, the dunes or grassy slopes on the other hand.
Zusammenfassung Über die Ökologie des Juncus balticus Willd. in Westiceland (Snaefellnes): die Pflanze wächst ausschließlich in den Kontaktzonen zwischen den Mooren einerseits und den Salzwiesen, den Dünen oder den Grasabhängen andrerseits.
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8.
25 populations from Turkey and one of Syria belonging to theSabulina section of the genusMinuartia have been karyologically examined. New chromosome numbers have been recorded forM. mesogitana andM. hybrida subsp.turcica, and a new variety was found in theM. hybrida complex. The origin of the taxa with n = 23 and n = 35 is discussed.
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9.
Zusammenfassung Bei der Aufnahme der Dosis-Effekt-Kurve für die Keimung vonPinus-Pollen nach UV-Bestrahlung in Suspension (etwa 0,4 mW/cm2, 265 nm) findet man bis zu 1,5 min Bestrahlungszeit eine deutliche Stimulation des Keimvorganges.
Stimulation of the germination of Pine Pollen by ultra-violet irradiation
Summary When investigating the dose-effect-curve of the germination of pine pollen after uv irradiation in suspension (approx. 0.4 mW/cm2,265 nm) one gets a significant stimulation of the germination process up to 1.5 min of irradiation.
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10.
The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.
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11.
Trapelia coarctata is lichenized withChlorella saccharophila var.ellipsoidea; this is in accordance with one of two former statements. The cells of the isolated alga may be covered individually by a gelatinous envelope; they also can be embedded in confluent mucilage. The course of succedanous divisions leading to the formation of autospores starts with the appearance of a second, new pyrenoid and goes on with bipartioning of the chloroplast, nuclear division and cytokinesis. Starch grains identical to those in the stroma surround the pyrenoid more or less loosely and not in the form of saucer-shaped parts constituting a coherent shell.
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12.
Chaenothecopsis consociata regularly is lichenized withDictyochloropsis symbiontica, nova spec., a member of theChlorococcales. During early developmentChaenothecopsis consociata possibly parasitizes onChaenotheca chrysocephala.Dictyochloropsis symbiontica is characterized by its hollow spherical chloroplast which consists of a complex threedimensional network, the absence of a pyrenoid, and the possession of one central nucleus. It reproduces by autospores as well as by zoo- and aplanospores.
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13.
Zusammenfassung Der Hypophysenhinterlappen von Ratten, die einer Dehydratation unterworfen waren, wurde ultrastrukturell-morphometrisch untersucht. Als wichtigster Befund wurde bereits nach 36stündiger Dehydratation eine massive Abnahme der Neurosekretgranula festgestellt. Gleichzeitig ist ein signifikanter Anstieg der Fettkörper in den Pituicyten zu verzeichnen. Die Fettkörper können nach Ansicht der Autoren als Endprodukt der Membranreste oder der Trägersubstanz des Neurohormons interpretiert werden. Eine Mitbeteiligung der Lysosomen bei ihrer Verarbeitung wird diskutiert.
Morphometric-ultrastructural investigations on the neural lobe of dehydrated rats
Summary The neurohypophysis of the rat after dehydration has been studied by electron microscopic and morphometric methods. As the main result we found a massive decrease of the neurosecretory granules already at a dehydration of 36 hours. At the same time one can note a significant increase of fat vacuoles in the pituicytes. These fat vacuoles could be the final product of residual membranes or of the carrier substance of the neurohormones. The possibility of a functional role of lysosomes in the catabolism is discussed.
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14.
Zusammenfassung Auf Grund der physiologischen Merkmale einer in Paramecium bursaria Ehrbg. auftretenden Chlorella ergibt sich eine systematische Zuordnung in den Formenkreis um Chlorella vulgaris f. tertia Fott et Nováková und Chlorella vulgaris var. vulgaris Beijerinck. Hiervon abweichende Befunde anderer Autoren werden diskutiert.
On the taxonomy of an auxotrophic Chlorella isolated from Paramecium bursaria ehrbg
An auxotrophic Chlorella has been isolated from Paramecium bursaria Ehrbg. and cultivated in mass culture in an inorganic medium supplied with vitamins B1 and B12. With regard to its physiological properties it is not identical with either one of the so far known Chlorella species. It belongs, however, to the group of Chlorella vulgaris f. tertia Fott et Novaková and Chlorella vulgaris var. vulgaris Beijerinck.
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15.
The phycobiont ofCatolechia wahlenbergii belongs to a new genus of theChlorococcales. It has mostly ellipsoidal, more rarely spherical cells with one bilobate through-shaped chloroplast and in general alveolar cytoplasm. Reproduction occurs by 2 or 4 autospores as well as by 16 or 32 motionless, small rodlike spores, which are formed and released in the same way as zoospores. They are aplanospores, and their formation apparently is fixed genetically, and not modificatorily, as in other species.
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16.
Chemical composition and physical parameters of waters from the Loire estuary were examined in 1981–1982 in order to assess water quality. It appears that riverflow is of first importance on suspended matter load, dissolved nutrient concentrations and oxygenation. The annual hydrological cycle is made of two periods. During the first one low riverflow, low nutrient concentrations, high suspended matter load and oxygen depletion are noticed. During the second one higher riverflows occur accompanied with increasing nutrient concentrations, decreasing turbidity and restoration of dissolved oxygen. Results indicate that annual inputs of dissolved nutrients attain 60 000 t a–1 for nitrogen, 2 400 t a–1 for phosphorus and 100 000 t a–1 for silica. It is suggested that the high suspended matter loading (1 million t a–1) is a significant factor disturbing oxygenation and by the way limiting water quality within the estuary.
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17.
Summary Parischnogaster jacobsoni, studied in Malaysia, presents long linear nests and haplometrotic nest foundation. In mature colonies more than one fertilized female and at least one potential egg layer can be found. Dominance-subordinance interactions are correlated with the reproductive potential of the females and with the division of labour. This species resemblesParischnogaster nigricans serrei, studied in Java, in its biology, nest architecture and social organization.
Biologie sociale deParischnogaster jacobsoni (du Buysson) (Hymenoptera Stenogastrinae)
Resume Parischnogaster jacobsoni, qui a été étudiée en Malaisie, a de longs nids linéaires et présente une fondation du nid haplométrotique. Dans les colonies mûres on retrouve communément plus d'une femelle fertilisée et au moins une femelle qui peut pondre. Les interactions de dominance-subordination sont liées au potentiel reproductif des femelles et à la division du travail. La biologie, l'architecture du nid et l'organisation sociale de cette espèce ressemblent à celles deParischnogaster nigricans serrei, qui a été étudiée à Java.
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18.
A new class of mycotoxins has been characterized from a strain of Aspergillus fumigatus: the fumitoxins A, B, C and D. The in vitro production of these metabolites is studied. Fumitoxins are common in cultures extracts of most strains of A. fumigatus. They are not detected from A. fischeri. Variations of the levels of these products during the incubation of cultures, and also by using different media, are noted. At all events, the toxicity of crude extracts of the mould, for the chick embryo, is equal to the one of the fumitoxins.
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19.
Ducellieria chodati Teiling is an organism rarely mentioned from plankton samples. Its propagation was unknown, and all earlier authors have failed to see that it is a colourless organism. Because of its structure and some chemical reactions,Ducellieria was thought to be a member of theXanthophyceae. Many living coenobia ofD. chodati from several Austrian lakes and some steps of their reproduction have been studied: Zoospores with two unequal flagella are released. After a mobile phase they settle on coniferous pollen grains drifting in water. Inside the pollen grain, a tube or flask is developed from which zoospores are released again after one or two days. These aggregate to form newDucellieria coenobia. These observations suggest thatDucellieria chodati belongs to thePhycomycetes, perhaps to theSaprolegniales.
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20.
Eusynaptomyces benjaminii is described as a new species of the ectoparasiticLaboulbeniales (Ascomycetes). It exists only on two very restricted areas of the body (= position specifity) of its hostEnochrus testaceus (F.) (Coleoptera, Hydrophilidae): on the claws of the right fore-leg and on the lower side of the frontal border of the pronotum. In these two habitatsEu. benjaminii develops two extremely different growth-forms. Male and female hosts are parasitized on somewhat different parts of their body. This can be explained by their mating behaviour. The growth-forms ofEu. benjaminii are so different that one ignorant of the biology of hosts and parasites, might regard them as members of different species or even genera. They are to be interpreted as adaptations of one species to growth positions and mating behaviour of the host. There is no sex-of-host specifity as assumed by certain authors for several species of theLaboulbeniales.
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