TY - JOUR A1 - Knecht, Sigrid A1 - Scheer, Ulrich T1 - Lautäußerung und Verhalten des Azoren-Buchfinken (Fringilla coelebs moreletti Pucheran) N2 - Einleitung und Methode S. 155. - Brutbiologie S. 155. - Motivgesang S. 157. - Sozialruf (Social Call) S. 161. - Entwicklung des Sozialrufs S. 164. - Brumimmungsruf (Regenruf) S. 165. - Flugruf S. 166. - Alarmruf eines Jungvogels S. 167. - Bestimmung der ReviergroBe S. 167. - Zusammenfassung S. 168. - Summary S. 168. - Literaturverzeichnis S. 169. Es wird untersucht, ob die Azoren-Buchfinken "Rassengesang" und "Rassenrufe" haben. Gesange und Rufe wurden auf Tonband aufgenommen und klangspek trogra phiert. Motivgesang. Jedes cJ beherrscht 2-6 verschiedene Gesangsformen, wobei stets eine "Alltagsform" mit der stark vereinfachten Phrase di-djah endigt. Die anderen, weniger haufigeren Gesangsformen ("Sonntagsformen") zeigen eine besser ausgearbeitete Endphrase, die jedoch nie so kompliziert wie bei kontinentalen Buchfinken ist. In Gebieten, in denen sich bevorzugt Kanarienvogel aufhalten, konnen Buchfinken Gesangselemente iibernehmen. Sozialruf. Das kontinentale pink ist auf alIen Azoreninseln durch ga ersetzt, so daB man von einem Rassenruf sprechen kann. Er ist mit starker Aggressionsneigung verkniipft. Der Sozialruf zeigt einen weiten Frequenzumfang, hervorgerufen durch mehrere simultane Noten. Brutstimmungsruf (Regenruf). Eine Anzahl verschiedener Rufe wurde spektrographiert. Vom cJ ist er bei maBiger Gefahr, aber auch spontan (30-70 Rufe/Min.) zu horen. Flugruf. Er scheint mit dem Flugruf der Nominatform identisch zu sein. Bestimmung der Reviergrope. Ein cJ wurde innerhalb seines Reviers an die "akustische Leine" genommen und bis zu den Reviergrenzen gezogen. Verhalten und LautauBerung anderten sich in Abhangigkeit von der jeweiligen Entfernung bis zur Reviergrenze. N2 - The attempt was made to determine whether Azores chaffinches possess a "racial song" or "racial calls". The songs and calls were tape-recorded and sound-spectrographs were prepared. 1. The song motif. Each cJ possesses 2-6 different song types, among which there is an "everyday type" which always ends with the greatly simplified phrase: dee-chah. The other, less frequent song types ("Sunday types") exhibit a more developed final phrase, though this is not as complex as that of Continental chaffinches. In areas where canaries commonly occur, chaffinches may adopt some of their song elements. 2. The social call. The Continental pink is replaced by gai in all of the Azores island forms, so it is justifiable to speak of a "racial call". This call is correlated with a strong aggressive tendency; it exhibits a broad frequency range based upon simultaneous utterance of several notes. 3. The brooding call ("rain-call"). A number of different calls were spectrographed. With the cJ, this call can be heard in response to mild danger and also as a spontaneous utterance (30-70 calls /min.). 4. Flight call. This seems to be identical to the flight call of the nominate type. 5. Determination of territory size. A cJ was led within his territory on an "acoustical lead" and drawn to his territorial boundaries. His. behaviour and vocalizations altered in relation to the distance from the territorial boundary. KW - Tierpsychologie Y1 - 1968 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39479 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Franke, Werner W. T1 - Negative staining and adenosine triphosphatase activity of annulate lamellae of newt oocytes N2 - Semi -iso la ted annul a te lamellae were prepared from single newt oocy tes (Triturus alpestris) by a modified Call a n-T omlin technique. Such preparations were examined with the electron mi croscope, and the negative sta ining a ppearance of th e a nnulate lamellae is described . The annul a te lamellae can be de tected either adhering to the nuclear envelope or being detached from it. Sometimes they a re obse rved to be connected with slender tubular-like structures interpreted as pa rts of the endoplasmic reti culum. The results obta ined from negativ e sta ining a re combined with those from sections. Especially, the structural data on th e a nnula te lamellae and the nuclear envelope of the very same cell were compa red . Evidence is presented th a t in the oocytes studied the two kinds of porous cisternae, n amely a nnul a te lamellae and nuclear envelope, a re markedly distinguished in that the annul a te lamellae ex hibit a much higher pore frequency (generally about twice tha t found for the corresponding nuclear envelope) and have al so a rela tive pore area occupying as much as 32 % to 55 % of th e cistern al surface (compa red with 13 % to 22 % in the nuclear envelopes). T he pore di ame ter a nd all other ultras tructural details of the pore complexes, however, a re equi valent in both kinds of porous cisternae. Like the annuli of the nuclear pore complexes of various a nimal and pl ant cells, the a nnuli of the a nnula te lamellae pores reveal al so an eightfold symmetry of their subunits in negatively stained as well as in ectioned ma teria l. Furthermore, th e a nnul a te lamellae a re shown to be a site of activity of the Mg-Na-Kstimul a ted ATPase. Y1 - 1969 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32087 ER - TY - JOUR A1 - Scheer, Ulrich T1 - Entwicklung der Gametogonien in ektopisch transplantierten Gonaden bei Triturus N2 - Nach homoplastischer Transplantation von larvalen Gonaden mit Fettkiirper in die vordere Leibeshiihle wiichst nur der Fettkiirper an der Leber an, so daB die Gonade nur indirekt mit dem Wirtsgewebe verbunden ist. Die Differenzierung der Gametogonien folgt der Normogenese, bei Ovartransplantationen entwickeln sich Auxocyten. Nach spatestens 27 Tagen ist die Blutversorgung wiederhergestellt. Homo- und autoplastische Transplantationen von Gonaden oh ne Fettkiirper ergeben fUr die Gametogonien eine vollig andere Entwicklung. Sind die Gonaden mit breiter Fliiche angewachsen, liiBt si ch bereits 7 Tage p.o. im Bereich der Kontaktzone Gonade-Leber die Karyolyse der Gametogonienkerne feststellen. Nach 3--4 Wochen stellt das Transplantat eine bindegewebige Zyste ohne Geschlechtszellen dar. Erythrozyten zeigen die Vaskularisation an. 1st nur ein Teil der Gonade mit der Leber verwachsen, zeigt der frei gebliebene Abschnitt eine normale Struktur mit Mitosen der Gametogonien. Die Degeneration der Geschlechtszellen hiingt offenbar von ihrer Lage zum extragonadalen Gewebe ab. N2 - Homografts of gonads including fat· bodies show fusion of the fat-body with liver tissue. Thus, contact between gonad and liver is only indirect. The differentiation of the gametogonia follows the normal way of development. In case of ovary homografts auxocytes appear. Not later than 27 days after transplantation vascularization is reestablished. Homo- and autografts of gonads without fat-body show a quite different development of the gametogonia. When the gonads are broadly fused with liver tissue one notices karyolysis of the gametogonia nuclei within the gonad liver contact region already 7 days after transplantation. After 3- 4 weeks the graft represents a cyst formed by connective tissue without any germ cells. Erythrocytes indicate vascularization. In the gonad partly fused with liver normal structure and mitosis in the gametogonia appear in that part of the transplant not attached to liver tissue. The present experiments suggest that the degeneration of germ cells is depending on their position to extragonadal tissue. Y1 - 1969 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40510 ER - TY - JOUR A1 - Scheer, Ulrich T1 - The ultrastructure of the nuclear envelope of amphibian oocytes: a reinvestigation. III. Actinomycin D-induced decrease in central granules within the pores. N2 - No abstract available Y1 - 1970 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32110 ER - TY - JOUR A1 - Franke, Werner W. A1 - Scheer, Ulrich T1 - The ultrastructure of the nuclear envelope of amphibian oocytes: a reinvestigation. II. The immature oocyte and dynamic aspects N2 - No abstract available Y1 - 1970 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32102 ER - TY - JOUR A1 - Franke, Werner W. A1 - Scheer, Ulrich T1 - The ultrastructure of the nuclear envelope of amphibian oocytes: a reinvestigation. I. The mature oocyte N2 - 1 n order to review the contradictory statements on the ultrast ructure of the nuclear envelope, a study was undertaken combining section and negat ive stai ning electron microscopy on manually isolated oocyte nuclei and nuclear envelopes from six amphibian species including Anura as well as Urodela. The a ppeara nce of the negatively stained iso lated nuclear envelopes is described in deta il and the dependence on the preparation co nditions used is emphas ized . Pore complex structures such as pore perimeter, central granule, an nul ar components, interna l fibrils, and annu lus-attached fibrils could be identified by both techniques, negat ive staining and sect ions. Comparative studies show that no marked diffe rences ex ist in the structural data of the nuclear envelope among the investigated amphibians and the significance of the structural components is discussed. A model of the nuclea r pore complex based on the findings of the present investigation is prese nted. Y1 - 1970 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32098 ER - TY - JOUR A1 - Müller, R. A1 - Scheer, Ulrich T1 - Klangspektrographische Untersuchungen der Lautäußerung beim Krallenfrosch, Xenopus laevis N2 - No abstract available Y1 - 1970 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40529 ER - TY - BOOK A1 - Kartenbeck, J. A1 - Zentgraf, H. A1 - Scheer, Ulrich A1 - Franke, Werner W. T1 - The nuclear envelope in freeze-etching N2 - No abstract available KW - Anatomie Y1 - 1971 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40534 SN - 3-540-05538-X ER - TY - JOUR A1 - Franke, Werner W. A1 - Kartenbeck, Jürgen A1 - Zentgraf, Hanswalter A1 - Scheer, Ulrich A1 - Falk, Heinz T1 - Membrane-to-membrane cross-bridges. A means to orientation and interaction of membrane faces N2 - No abstract available Y1 - 1971 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32122 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Knecht, Sigrid T1 - Die Vögel der Azoren T1 - The birds of the Azores N2 - Während einer viermonatigen Reise zu allen neun Azoreninseln wurde der gesamte Brutvogelbestand dieses Archipels untersucht. Die Befunde sind in einer detaillierten Artenliste zusammengefaßt, ergänzt durch ökologische und brutbiologische Anmerkungen. Zahlreiche Beobachtungen lassen vermuten, daß vor allem Stieglitz und Kanarienvogel tägliche und auch jahreszeitlich bedingte interinsulare Flüge unternehmen. Die Lautäußerungen sechs verschiedener Vogel arten sind in Klangspektrogrammen dargestellt. Ein mathematischer Ansatz zeigt, daß sich die Anzahl der auf einer bestimmten Insel brütenden Landvogelarten umgekehrt proportional zur Entfernung zum europäischen Festland und proportional zum Logarithmus naturalis der Inselfläche verhält. Die abgeleitete Formel läßt sich prinzipiell auch auf andere Atlantikinseln anwenden, die weitgehend vom Festland isoliert sind. N2 - Observations of the breeding birds were performed during a four months journey of the nine Azores islands. The data are summed up in a detailed species-list supplemented by ecological notes as weIl as some comments upon the breeding behaviour. Several findings suggest that goldfinch and canary undertake daily and also seasonal flights between the islands. Songs and calls of six different species are represented in sound-spektrographs. A mathematical analysis shows that the species number of the breeding land birds of a certain island is indirectIy proportional to the distance between the island and the european continent and directly proportional to the natural logarithm of the island area. The deduced formula is also principly applicable for other atlantic islands which are largely iso la ted from the continent. Y1 - 1971 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39668 ER - TY - JOUR A1 - Franke, Werner W. A1 - Scheer, Ulrich T1 - Some structural differentiations in the HeLa cell: heavy bodies, annulate lamellae and cotte de maillet endoplasmic reticulum N2 - A small fraction of HeLa cells within an exponentially growing culture showed cisternal differentiations, such as cytoplasmic as well as intranuclear annulate lamellae and special smooth surfaced endoplasmic reticulum aggregates with a typical "Cotte de maillet" appearance. Additionally, clusters of dense granules were observed in the cytoplasm which were often associated with polysomes and strongly resembled the so-called "heavy bodies" known in particular in diverse oocytes. The functional meaning of these structures is discussed. Moreover, it is deduced from the ultrastructural identity of the pore complexes in the nuclear envelope and the cytoplasmic and intranuclear annulate lamellae that the pore complex material with its highly ordered arrangement is not a structure characteristic for nucleocytoplasmically migrating material, but rather is a general structural expression of a tight binding of ribonucleoprotein (RNP) to cisternal membranes. The pore complexes are thought of as representing sites of a RNP-storage. A similar functioning is hypothesized for the "heavy body"like aggregates. To the current hypotheses on the formation of annulate lamellae and the nuclear envelope, which are based on the concept of membrane continuities and constancies, the alternative view of a self assembly mechanism of membrane constituents on nucleoprotein structures is added. KW - Cytologie Y1 - 1971 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40614 ER - TY - JOUR A1 - Knecht, Sigrid A1 - Scheer, Ulrich T1 - Die Liste der Vogelarten von S. Miguel (Azoren) des Gaspar Fructuoso (gestorben 1591) N2 - No abstract available Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41402 ER - TY - JOUR A1 - Franke, Werner W. A1 - Scheer, Ulrich A1 - Fritsch, Hansjörg T1 - Intranuclear and cytoplasmic annulate lamellae in plant cells N2 - No abstract available Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32148 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Franke, Werner W. T1 - Annulate lamellae in plant cells: formation during microsporogenesis and pollen development in Canna generalis Bailey N2 - The occurrence of stacked annulate tamellae is documented for a plant cell system, namely for pollen mother cells and developing pollen grains of Canna generalis. Their structural subarchiteeture and relationship to endoplasmie reticulum (ER) and nuclear envelope cisternae is described in detail. The results demonstrate structural homology between plant and animal annulate lamellae and are compatible with, though do not prove, the view that annulate lamcllar cisternae may originate as a degenerative form of endoplasmic retieulum. Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32160 ER - TY - JOUR A1 - Franke, Werner W. A1 - Scheer, Ulrich T1 - Structural details of dictyosomal pores N2 - Structural details of the dictyosomal pores in several plant cell types are described from tangential and cross sections of Golgi cisternae. Frequency distributions of the sizes of such Golgi pores are given and compared with the corresponding values of nuclear pores in the same cells. Golgi pore inner diameters are less homogeneously distributed and can be as small as 100 A or less. They are not simply cisterna I holes, but are often associated with centrally located electron dense granules or rods and with inner pore filaments. This organization, which is very common in dictyosomal pores in plant and animal cells, has some similarities with the structural architecture of nuclear envelope and annulate lamellar pore complexes. The particulate material associated with the dictyosomal pores shows spatial and structural relationship to cytoplasmic ribosomes. Possible modes of Golgi pore formation and some consequences of these observations for interpretation of nuclear pore structures are discussed. Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32155 ER - TY - JOUR A1 - Franke, Werner W. A1 - Kartenbeck, Jürgen A1 - Krien, S. A1 - VanderWoude, W. J. A1 - Scheer, Ulrich A1 - Morré, D. J. T1 - Inter- and intracisternal elements of the Golgi apparatus: A system of membrane-to-membrane cross-links N2 - Electron opaque cross-bridge structures span the inter- and intracisternal spaces and provide membrane-to-membrane connections between adjacent cisternae of dictyosomes of pollen tubes of Clivia and Lilium. Additionally, the classic intercisternal rods, characteristic of intercisternal regions near the maturing face of dictyosomes, are connected with the adjacent membranes through similar cross-bridge elements. We suggest that these structural links are responsible for maintaining the flattened appearance of the central parts of Golgi apparatus cisternae as well as for the coherence of cisternae within the stack. Observations on other plant (e.g. microsporocytes of Canna) and animal cells (e.g. rodent liver and hepatoma cells, newt spermatocytes) show that such an array of membrane cross-links is a universal feature of Golgi apparatus architecture. The cross-bridges appear as part of the complex "zone of exclusion" which surrounds dictyosomes, entire Golgi apparatus and Golgi apparatus equivalents in a variety of cell types. KW - Golgi apparatus KW - Membranes KW - Cross-bridges KW - Electron microscopy Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39514 ER - TY - JOUR A1 - Scheer, Ulrich T1 - The ultrastructure of the nuclear envelope of amphibian ooctyes: IV. On the chemical nature of the nuclear pore complex material N2 - In order to investigate the chemical composition of the nuclear pore complexes isolated nuclei from mature Xenopus laevis oocytes were manually fractioned into nucleo· plasmic aggregates and the nuclear envelopes. The whole isolation procedure takes no more than 60- 90 sec, and the pore complexes of the isolated envelopes are well preserved as demonstrated by electron microscopy. Minor nucleoplasmic and cytoplasmic contaminations associated with the isolated nuclear envelopes were determined with electron microscopic morphometry and were found to be quantitatively negligible as far as their mass and nucleic acid content is concerned. The RNA content of the fractions was determined by direct phosphorus analysis after differential alkaline hydrolysis. Approximately 9% of the total nuclear RNA of the mature Xenopus egg was found to be attached to the nuclear envelope. The nonmembranous elements of one pore complex contain 0.41 X 10- 16 g RNA. This value agrees well with the content estimated from morphometric data. The RNA package density in the pore complexes (270 X 10- 15 g/fJ-3) is compared with the nucleolar, nucleoplasmic and cytoplasmic RNA concentration and is discussed in context with the importance of the pore complexes for the nucleo-cytoplasmic transport of RNA-containing macromolecules. Additionally, the results of the chemical analyses as well as of the 3H-actinomycin D autoradiography and of the nucleoprotein staining method of Bernhard (1969) speak against the occurence of considerable amounts of DNA in the nuclear pore complex structures. KW - Nuclear envelope KW - Amphibian oocytes KW - Nuclear pore complex KW - Chemical nature KW - Electron microscopy Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39500 ER - TY - JOUR A1 - Eckert, W. A. A1 - Franke, Werner W. A1 - Scheer, Ulrich T1 - Actinomycin D and the central granules in the nuclear pore complex: thin sectioning versus negative staining N2 - Thin section electron microscopy of Actinomycin D treated Tetrahymena cells and amphibian oocytes (Xenopus laevis, Triturus aZpestris) reveal no reduction in the central granules in the nuclear pore complexes. Possible reasons for the diversity between these results and earlier observations using negatively stained isolated nuclear envelopes from the same objects are discussed. The results clearly show that the presence of central granules within the nuclear pores does neither depend on nuclear RNA synthesis nor does indicate nucleocytoplasmic RNA transport. This conclusion leads to a reconsideration of the nature of the central granule. The functioning of the central granule of the nuclear pore complexes is further discussed in connection with recent studies on the ultrastructure of various types of cisternal pores. KW - Nuclear pores KW - Nucleocytoplasmic exchange KW - Actinomycin D KW - Tetrahymena KW - Amphibian oocytes Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40636 ER - TY - JOUR A1 - Derksen, J. A1 - Trendelenburg, Michael F. A1 - Scheer, Ulrich A1 - Franke, Werner W. T1 - Spread chromosomal nucleoli of Chironomus salivary glands N2 - No abstract available Y1 - 1973 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32209 ER - TY - JOUR A1 - Franke, Werner W. A1 - Trendelenburg, Michael F. A1 - Scheer, Ulrich T1 - Natural segregation of nucleolar components in the course of plant cell differentiation N2 - Segregation of the nucleolar components is described in the differentiated nucleus of the generative cell in the growing Clivia and Lilium pollen tubes. This finding of a natural nucleolar segregation is discussed against the background of current views of the correlations of nucleolar morphology and transcriptional activity. Y1 - 1973 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32182 ER -