Peat record reflecting Holocene climatic change in the Zoige Plateau and AMS radiocarbon dating

Through the use of reliable AMS dating of high resolution (15-30 years) peat and the establishment of monsoon climate proxies sequence, we have been able to recognize several cold, dry events in the Tibetan Plateau during the Holocene. The more obvious ones occurred around 12800, 11300, 10200, 9580, 8900, 6400, 4400, 3700, 2800 and 1500 cal. aBP. These events correlate well with both ice rafting events recorded in high latitude North Atlantic Ocean sediment cores and cooling events in the low latitude SST. Spectral analysis indicates high frequency climate variation on centennial-millennial time scale during the Holocene. This further reflects Holocene climate instability and the existence of centennial-millenium scale rhythm in mid latitude areas as well.     

The DNA sequence of human chromosome 21

Chromosome 21 is the smallest human autosome. An extra copy of chromosome 21 causes Down syndrome, the most frequent genetic cause of significant mental retardation, which affects up to 1 in 700 live births. Several anonymous loci for monogenic disorders and predispositions for common complex disorders have also been mapped to this chromosome, and loss of heterozygosity has been observed in regions associated with solid tumours. Here we report the sequence and gene catalogue of the long arm of chromosome 21. We have sequenced 33,546,361 base pairs (bp) of DNA with very high accuracy, the largest contig being 25,491,867 bp. Only three small clone gaps and seven sequencing gaps remain, comprising about 100 kilobases. Thus, we achieved 99.7% coverage of 21q. We also sequenced 281,116 bp from the short arm. The structural features identified include duplications that are probably involved in chromosomal abnormalities and repeat structures in the telomeric and pericentromeric regions. Analysis of the chromosome revealed 127 known genes, 98 predicted genes and 59 pseudogenes.     

工作流引擎在继电保护管理系统中的应用

继电保护管理系统中关键业务的应用开发离不开工作流技术的支持。针对于此,通过对系统的实际开发需求的分析,在传统的关系数据库的基础上,提出了一个适用于关键业务开发的基于关系数据库的轻量级工作流引擎的框架结构。深入讨论了采用关系数据库来设计工作流引擎的原因,并详细地给出了相关的设计原理以及具体的表示和实现方法。其原型已经应用到实际的继电保护管理系统中。实践证明,利用此工作流引擎可以显著地缩短业务的开发周期。     

Der Oxytocingehalt im menschlichen pathologischen Liquor

Summary The quantity of oxytocin in the cerebrospinal fluid is decreased by brain atrophy and infantile brain damage, not injured by multiple sclerosis but increased by meningitis, sciatica and drug controlled convulsions. Immediately after a seizure, the oxytocin level is very strong raised.

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Diese Arbeit wurde mit Mitteln des Ministeriums für Wissenschaft und Technik der DDR durchgeführt.     

Recombination frequency and DNA content of the distal part of the second chromosome ofDrosophila hydei sturtevant

Summary Four visible markers, including a newly isolated one, have been cytologically mapped on the second chromosome ofDrosophila hydei. Both the frequency of recombination and the amount of DNA between these markers have been determined. From these data the coefficient of exchange has been calculated.     

The effects of two neutral polymers on the geometry and deformability of the human erythrocyte

Summary Polyvinylpyrrolidone and dextran decrease cellular deformability. Changes in volume do not wholly account for the changes which imply a stiffening of the plasma membrane. The effects differ from those induced by charged macromolecules.The work was supported by the Medical Research Council of Canada.     

Molecular deficiencies of human blood coagulation

Summary Blood coagulation reflects, the complex biological system resulting in the formation of thrombin and the subsequent conversion of fibrinogen into fibrin. Disorders of either thrombin or fibrin formation may cause bleeding states. Congential hemorrhagic disorders are characterized by either reduction of a coagulation factor or impairment of its functional capacity by structural aberrations. Immunological studies and direct molecular evaluation of fibrinogen demonstrate that both types of abnormalities occur. Functional evaluation of abnormal fibrinogens suggests that many different structural variants exist and variably influence interaction with thrombin, fibrin polymerization and fibrin stabilization. Similar studies performed on factors II, VII, VIII, IX, X and XIII indicate that qualitative abnormalities are more frequent than true deficiency states. Such molecular abnormalities will become increasingly interesting and important as the biochemistry of normal coagulation progresses.

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Zusammenfassung Blut gerinnt, wenn das Gerinnungsferment Thrombin aktiviert wird und Fibrinogen in Fibrin umwandelt. Störungen der Thrombin- oder Fibrinbildung können Bluterkrankheiten verursachen. Die Ursache angeborener Bluterkrankheiten liegt entweder in der quantitativen Verminderung oder in qualitativen Strukturanomalien eines Gerinnungsfaktors. Immunologische Methoden im Verein mit einer beginnenden, direkten Strukturabklärung zeigten für das Fibrinogen überzeugend, dass beide Möglichkeiten vorkommen. Unterschiedliche Funktionsausfälle von Fibrinogen lassen vermuten, dass verschiedenartigen Strukturanomalien für Störungen der Substrateigenschaften gegenüber Thrombin, der Polymerisierung oder der Fibrinstabilisierung verantwortlich sind. Ähnliche Untersuchungen an den Faktoren II, VII, VIII, IX, X und XIII zeigen, dass wahrscheinlich die Mehrzahl der bekannten Bluterkrankheiten durch Strukturanomalien verursacht werden. Die eingehende Untersuchung solcher Strukturdefekte wird zukünftig um so interessanter und bedeutungsvoller werden, je besser die Struktur und Funktion der normalen Gerinnungsfaktoren bekannt sind.