Complete robertsonian fusion in the malaysian lesser mouse-deer (Tragulus javanicus)

Zusammenfassung Der malayische Tragulid (Tragulus javanicus) besitzt 2n=32. Alle Chromosomen sind entweder metazentrisch oder submetazentrisch, wobei die metazentrischenY-Chromosomen am kleinsten sind. Die Sex-Chromosomen sind vom gewöhnlichen Typ, während ein Autosomenpaar durch das Vorhandensein einer sekundären Konstriktion charakterisiert ist.     

Robertsonian fusion between homologous chromosomes in a natural population of the least cotton rat,Sigmodon minimus (Rodentia,Cricetidae)

Zusammenfassung Die diploide Chromosomenzahl vonSigmodon minimus, einem Nager der Familie der Cricetiden ist 30. Im Karyotyp befindet sich kein grosses metazentrisches Chromosom. Bei Tieren aus einer Population von Silver City, New Mexico, wurden 29 Chromosomen gefunden. Eines davon war relativ gross und metazentrisch. Beim Paaren der Chromosomen in Meiose ist es evident, dass das metazentrische Chromosom das Fusionsprodukt von 2 homologen Chromosomen ist.

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The author wishes to thank Dr. J.Wright, Dr. J. S.Findley and Mr. J. T.Mascarello for their assistance in procuring the live specimens.     

Robertsonian chromosomal polymorphism in the mouse (M. musculus domesticus)

Zusammenfassung Hausmäuse (M. m. domesticus) aus dem Bergell/GR zeigen einen intraspezifischen Chromosomenpolymorphismus vomRobertson'schen Typ mit wenigstens zwei verschiedenen metazentrischen Chromosomen. Für eines dieser beiden Chromosomen konnte gezeigt werden, dass es von den sieben bei der Tabakmaus (M. poschiavinus) vorhandenen metazentrischen Chromosomen unabhängig ist. Ein für dieses Chromosom (T8Bnr) homozygoter Stamm auf dem Hintergrund der Laboratoriumsmaus wird für experimentelle Verwendung herausgezüchtet.

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Work supported by Landesamt für Forschung, Nordrehein-Westfalen.     

Robertsonian translocations in the Malayan house shrew,Suncus murinus (Insectivora,Soricidae)

Zusammenfassung Zwei neue Chromosomen (2n=36 und 37; früher 38, 39 und 40) wurden in der malayischen SpitzmausSuncus murinus gefunden und als numerische Variationen der Robertsonschen Translokation zugeschrieben. Es wird angenommen, dass es sich um zwei Arten von Translokation» handelt die metazentrisch mitwirkten und woraus die Produktion 9 karyotypischer Klassen resultiert.     

Robertsonian fusion leading to the formation of stable dicentric chromosome in an ascites cell line of the mouse

Summary The dicentric nature of a marker metacentric chromosome originated by robertsonian fusion has been established in the ascites cells of mouse sarcoma 180. C-banding analysis has revealed that the metacentric is actually a dicentric with 2 closely situated C-positive heterochromatic zones. The nature of the centromeres and the NF value of the cell indicate that this meta-dicentric marker has orginated by breakage and fusion within each of the short arms of 2 acrocentric chromosomes.Acknowledgment. Grateful acknowledgment is made to Dr N. Chatterji, former Director, CNCRC, Calcutta, for supplying the cell-line to the first author. Sincere thanks are due to Prof. Sujit K. Dasgupta, Head, Dept. of Zoology, H. M. Govt. College and to Dr A. K. Roy of the same department for encouragement.     

Development of thermoregulation in the newborn lesser bushbaby (Galago senegalensis moholi,Smith 1839)

Summary The temperature-regulating system in bushbabies operates from the 1st day of life. The postnatal metabolism decreases from the 5th (2.9 ml O₂/g·h) to the 140th day (0.7 ml O₂/g·h) to the level of the adults.This work was undertaken with the aid of the Deutsche Forschungsgemeinschaft and Prof. Dr. E.Kulzer.     

Nuclear science and technology in the Malaysian context: Three phases of technoscientific knowledge transfer (ETTLG)

This essay considers the development of the nuclear science programme in Malaysia from a transnational perspective by examining the interactions between state agents and other external nuclear-knowledge/technology related actors and agents. Going beyond the model of knowledge diffusion that brings together concerns articulated in Harris’s (2011) geographies of long distance knowledge and Reinhardt's (2011) role of the expert in knowledge transfer, the proposed three-phase model of knowledge transfer theorises the pathways undertaken by a late-blooming participant of modern science and technology as the latter moves from epistemic dependency to increasing independence despite the hurdles encountered, and the underdevelopment of many areas of its technoscientific economy. The model considers tensions stemming from the pressures of expediency for meeting national developmental goals on the one side, and the call to support the objectives of basic science on the other. The three phases of the model are epistemic transition, epistemic transplantation and localisation, and epistemic generation (ETTLG). As additional support for the proposed model, three arguments are proffered as deeper explanations of the epistemic goal by using Malaysia as a case study: knowledge transfer for political legitimization, knowledge transfer for countering agnotology, and knowledge transfer for social engineering and science diplomacy.     

Centric fusion in the malayan house rat,Rattus rattus diardii (Rodentia,Muridae)

Zusammenfassung Bei einem Männchen vonRattus rattus diardii aus Kuala Lumpur (Malaysia) wurden 41 Chromosomen (normal 2n = 42) gefunden, was mit der Robertson'schen Translokation in Zusammenhang stehen dürfte, welche die Fusion 2 einarmiger Autosomen in ein grosses, zweiarmiges Chromosom vollzieht.     

Complete development ofAncylostoma ceylanicum (Looss, 1911) in golden hamsters,Mesocricetus auratus

Zusammenfassung Es gelang, den HakenwurmAncylostoma ceylanicum an den Goldhamster zu adaptieren, was zur Vereinfachung chemotherapeutischer Versuche bei der Bekämpfung dieses tierischen und menschlichen Parasiten im Laboratorium beitrug.     

Complete development of human hookworm,Ancylostoma duodenale (Dubini, 1843) in infant rabbits

Summary Establishment of a patent infection ofAncylostoma duodenale in the laboratory host, infant rabbit, is successfully achieved.Acknowledgments. We thank Dr B.B. Gaitondé, Haffkine Institute, for his encouragement and advice in this work.     

Robertsonian translocation,pericentric inversion and heterochromatin block in the evolution of the Tailless Fruit Bat

Summary The karyotype ofMegaerops ecaudatus from Peninsular Malaysia consists of 24 chromosomes as compared to 2n=26 for specimens from Thailand. The difference in diploid number is the result of Robertsonian translocation. The Peninsular Malaysian specimens also exhibit pericentric inversion in the smallest pair of autosomes, and the presence of a totally heterochromatic short arm in the second longest metacentric pair. There is 1 pair of Ag-NOR, located on the secondary constriction of the longest metacentric autosome.This work is supported by a University of Malaya research grant.     

Intergeneric interactions betweenEimeria separata (Apicomplexa) andNippostrongylus brasiliensis (Nematoda) in the rat

Summary Ova production inNippostrongylus brasiliensis infected rats was significantly greater than in rats singly infected with the helminth whenEimeria separata infections were introduced 4, 6 and 11 days postinoculation withN. brasiliensis. Patent periods were unaltered during concurrent infections. These results suggest that the presence ofE. separata affects helminth fecundity but does not increaseN. brasiliensis longevity as has been shown withE. nieschulzi.This study was supported by NIH MB RS Grant RRO8012-8.     

Occurrence of dihydromurexine (Imidazolepropionylcholine) in the hypobranchial gland ofThais (purpura)haemastoma

Riassunto Gli estratti metanolici di organo ipobranchiale diThais (purpura)haemastoma contengono cospicui quantitativi di un nuovo estere della colina, la diidromurexina o imidazolpropionilcolina. La base è localizzata esclusivamente nella striscia mediana giallastra dell'organo ipobranchiale, ove può raggiungere concentrazioni dell'ordine di 15–17 mg per g di tessuto fresco.

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Supported by grants from the Consiglio Nazionale delle Ricerche, Roma.