Zur Brutbiologie des Schilfrohrs?ngers,Acrocephalus schoenobaenus L

Ohne Zusammenfassung     

Erster Brutnachweis des Bindenkreuzschnabels (Loxia leucoptera) in Mitteleuropa

Zusammenfassung Der Bindenkreuzschnabel (Loxia leucoptera) brütete 1991 in einem Paar erfolgreich auf einem Berliner Friedhof und damit erstmals sicher in Mitteleuropa. Zwei Jungvögel wurden am 29. Mai flügge. Die Baumschicht des Friedhofs besteht zu 80 % aus Laubholz und nur zu 20 % aus Nadelholz, d. h. die Art wählte hier den offenen, gemischten Laubwaldtyp. Dieser Nachweis ist mit einer sehr großen Invasion von Kreuzschnäbeln nach Mittel- und Westeuropa in Verbindung zu bringen. Einige die bisherigen Erkenntnisse ergänzende Beobachtungen werden zu Gefiedermerkmalen, Verhalten und stimmlichen Äußerungen mitgeteilt.

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First breeding record of Two-barred Crossbill (Loxia leucoptera) in Central Europe

Summary In 1991, a pair of Two-barred Crossbills bred successfully on a cemetery of Berlin, which is the first certain breeding record in Central Europe of this species. Two young fledged May 29. The tree stand of the cemetery consists of 80 % deciduous trees and 20 % conifers only, which means the selection of an open, mixed deciduous forest type. This event has to be seen in connection with a very intense invasion of Crossbills to Central and Western Europe. Some notes are given on plumage characters, behaviour and vocalizations.

     

Untersuchungen über die immunhistochemische Fibrindarstellung an Biopsie- und Obduktionsmaterial

Zusammenfassung Mit Hilfe der direkten immunhistochemischen Methode ist ein spezifischer Fibrinnachweis möglich. Um die praktische Anwendung der Methode für wissenschaftliche und diagnostische Fragestellungen der Humanpathologie zu prüfen, bei der in der Regel kein Frischgewebe zur Verfügung steht, wurden Untersuchungen an unterschiedlich altem und unterschiedlich vorbehandeltem Biopsie- und Obduktionsmaterial durchgeführt. Dabei zeigt sich, daß die Antigenität des Fibrins sehr stabil ist und auch postmortal lange erhalten bleibt, so daß die Methode für den Fibrinnachweis auch am Obduktionsmaterial gut geeignet ist.

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Summary A specific demonstration of fibrin was made possible by means of a direct immunohistochemical method. To test its use for scientific and diagnostic problems in human pathology — for which, as a rule, fresh material is not available — tests were carried out on material obtained by biopsy and autopsy (Tissues of various age and different pre-treatment). It was possible to demonstrate that the antigenicity of fibrin is maintained over long periods. The method is therefore especially suitable for the demonstration of fibrin in post mortem material.

     

Der statische Sinn der Medusen

Ohne Zusammenfassung     

Über Photomenotaxis bei Elysia viridis Mont

Ohne Zusammenfassung Elysia viridis findet sich reichlich zusammen mit andern Opisthobranchiern auf grünen Algen in den Häfen St. Lucia und Mergelina in Neapel.     

CFD Based Determination of Aerodynamic Effects on Birds with Extremely Large Dihedral

Using a sophisticated aerodynamic method, the effects of extremely large dihedral on the aerodynamic characteristics of birds are determined. With this method, it is possible to generate solutions for the addressed aerodynamic problem, which shows a high complexity due to interference effects caused by dihedral and pronounced 3-dimensional flow properties as well as due to complex wing geometries. From the obtained results it follows that extremely large dihedral has substantial effects on the aerodynamic force characteristics. There are significant changes in the lift, the drag and the side force, thus affecting the flight performance. Furthermore, the obtained results show that the aerodynamic rolling and yawing moment characteristics are influenced by extremely large dihedral to a high degree. This is a significant outcome for lateral-directional stability because the aerodynamic rolling and yawing moment characteristics have a determinative influence here.     

Rigid matrix supports osteogenic differentiation of stem cells from human exfoliated deciduous teeth (SHED)

Stem cell fate can be induced by the grade of stiffness of the extracellular matrix, depending on the developed tissue or complex tissues. For example, a rigid extracellular matrix induces the osteogenic differentiation in bone marrow derived mesenchymal stem cells (MSCs), while a softer surface induces the osteogenic differentiation in dental follicle cells (DFCs). To determine whether differentiation of ectomesenchymal dental precursor cells is supported by similar grades of extracellular matrices (ECMs) stiffness, we examined the influence of the surface stiffness on the proliferation and osteogenic differentiation of stem cells from human exfoliated deciduous teeth (SHED). Cell proliferation of SHED was significantly decreased on cell culture surfaces with a muscle-like stiffness. A dexamethasone-based differentiation medium induced the osteogenic differentiation of SHED on substrates of varying mechanical stiffness. Here, the hardest surface improved the induction of osteogenic differentiation in comparison to that with the softest stiffness. In conclusion, our study showed that the osteogenic differentiation of ectomesenchymal dental precursor cells SHED and DFCs are not supported by similar grades of ECM stiffness.