Species difference in sensitivity to the diabetogenic action of triphenyltin hydroxide

Summary The sensitivity to the diabetogenic action of triphenyltin hydroxide (TPTOH) was investigated in 5 species of experimental animals. A single oral administration of TPTOH produced marked hyperglycemia and triglyccridemia in rabbits and hamsters, but no evidence of diabetes was found in mice, rats and guinea-pigs. No morphological abnormality was observed in islet tissue from TPTOH-treated hamsters.     

New, Unexpected Pyranose-Furanose Rearrangement Towards the Synthetic Studies on Rare Sugars and Nucleosides

Preparation of rare aminosugars such as N-acetylgalactosamine （GalNAc） in large quantities is of importance for the chemo-enzymatic synthesis of oligosaccharides. Starting from naturally abundant N-acetylglucosarnine （GIcNAc）, the regio-and stereoselective and new functional group transformation play important roles as the key reactions.     

上海中心城区道路灰尘中氯代多环芳烃的时空分布特征

选取了上海中心城区的道路灰尘作为研究对象, 运用气相色谱-质谱(gas chromatography-mass spectrometry, GC/MS)联用技术对道路灰尘中20种氯代多环芳烃(chlorinated polycyclic aromatic hydrocarbons, ClPAHs)进行了检测, 分析了道路灰尘中ClPAHs的时空分布特征和毒性当量(toxic equivalent quantity, TEQ)等. 结果表明, 11种ClPAHs的检出率均大于50%, 说明ClPAHs在上海中心城区道路灰尘中普遍存在. 研究区域内的ClPAHs浓度呈现出明显的季节特征, 即冬季>夏季, 冬季∑ClPAHs浓度最高为24.9 ng/g干重. 在空间分布上, 交通枢纽区浓度最高(冬季为21.2 ng/g干重, 夏季为10.7 ng/g干重), 建筑施工区、商业区次之, 近绿地区最低. 在道路灰尘中最主要的两个组分是6-ClBaP和7-ClBaA. ClPAHs在冬季和夏季的TEQ范围分别为0.01~4.81和0.01~1.78 ng-TEQ/g干重, 其中 7-ClBaA在ClPAHs总毒性当量中的贡献最大.     

Postjunctional potentials and cardiac acceleration in a mollusc (Dolabella auricula)

Zusammenfassung Nachweis, dass die Reizwirkung des Herz-Akzeleratornerven beim MoluskenDolabella auricula von der Reizfrequenz abhängt. Elektrische Ableitungen von einzelnen Herzkammerzellen zeigen, dass bei niedriger Reizfrequenz jedes nicht-summative «excitatory junctional potential» ein Aktionspotential des Herzens hervorruft.     

Species difference in sensitivity to the diabetogenic action of triphenyltin hydroxide

The sensitivity to the diabetogenic action of triphenyltin hydroxide (TPTOH) was investigated in 5 species of experimental animals. A single oral administration of TPTOH produced marked hyperglycemia and triglyceridemia in rabbits and hamsters, but no evidence of diabetes was found in mice, rats and guinea-pigs. No morphological abnormality was observed in islet tissue from TPTOH-treated hamsters.     

The Jurassic System in SW Japan: review of recent research

The present state of the art in Jurassic oceanicplate stratigraphy in Japan is the result of research over the last two decades. Radiolarian biochronology puts age constraints on the development of fore-arc basin deposits, which cover Permian and Jurassic accretionary complexes of the Outer Zone, facing the Pacific. Special attention is given to the “Torinosu-type” reef-limestone blocks in the Upper Jurassic-Lower Cretaceous fore-arc basin deposits that derived from a shallow-marine continental margin such as the Inner Zone shelf, facing Eurasia. Further progress was achieved in dating and defining sedimentary environments in the Inner Zone Tetori Group. Erosive events during the process of Jurassic accretion are also discussed in relation to the Late Mesozoic geologic and tectonic setting.     

Element-selective imaging of atomic columns in a crystal using STEM and EELS

Microstructure characterization has become indispensable to the study of complex materials, such as strongly correlated oxides, and can obtain useful information about the origin of their physical properties. Although atomically resolved measurements have long been possible, an important goal in microstructure characterization is to achieve element-selective imaging at atomic resolution. A combination of scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS) is a promising technique for atomic-column analysis. However, two-dimensional analysis has not yet been performed owing to several difficulties, such as delocalization in inelastic scattering or instrumentation instabilities. Here we demonstrate atomic-column imaging of a crystal specimen using localized inelastic scattering and a stabilized scanning transmission electron microscope. The atomic columns of La, Mn and O in the layered manganite La1.2Sr1.8Mn2O7 are visualized as two-dimensional images.