A process for controlling intracellular bacterial infections induced by membrane injury

Strategies for inhibiting phagolysosome fusion are essential for the intracellular survival and replication of many pathogens. We found that the lysosomal synaptotagmin Syt VII is required for a mechanism that promotes phagolysosomal fusion and limits the intracellular growth of pathogenic bacteria. Syt VII was required for a form of Ca2+-dependent phagolysosome fusion that is analogous to Ca2+-regulated exocytosis of lysosomes, which can be triggered by membrane injury. Bacterial type III secretion systems, which permeabilize membranes and cause Ca2+ influx in mammalian cells, promote lysosomal exocytosis and inhibit intracellular survival in Syt VII +/+ but not -/- cells. Thus, the lysosomal repair response can also protect cells against pathogens that trigger membrane permeabilization.     

Impact of anthropogenic CO2 on the CaCO3 system in the oceans

Rising atmospheric carbon dioxide (CO2) concentrations over the past two centuries have led to greater CO2 uptake by the oceans. This acidification process has changed the saturation state of the oceans with respect to calcium carbonate (CaCO3) particles. Here we estimate the in situ CaCO3 dissolution rates for the global oceans from total alkalinity and chlorofluorocarbon data, and we also discuss the future impacts of anthropogenic CO2 on CaCO3 shell-forming species. CaCO3 dissolution rates, ranging from 0.003 to 1.2 micromoles per kilogram per year, are observed beginning near the aragonite saturation horizon. The total water column CaCO3 dissolution rate for the global oceans is approximately 0.5 +/- 0.2 petagrams of CaCO3-C per year, which is approximately 45 to 65% of the export production of CaCO3.     

Volatile constituents of fermented sugar baits and their attraction to lepidopteran species

The volatile compounds emanating from four fermented sugar baits, palm sugar, golden cane syrup, port wine, and molasses, were isolated by headspace sampling and analyzed by gas chromatography-mass spectrometry. Three classes of compounds including esters, alcohols, and aromatic compounds were identified in the headspace of the four fermented sugar baits. There was a high degree of qualitative similarity between the headspace contents of the four fermented sugar baits, although quantitatively they varied considerably. Ethyl acetate, 3-methylbutanol, ethyl hexanoate, 2-phenylethanol, ethyl octanoate, ethyl (E)-4-decenoate, ethyl decanoate, and ethyl dodecanoate were the major compounds identified in the headspace of the four fermented sugar baits. The efficacy of the four fermented sugar baits was investigated in field trapping experiments. Fermented palm sugar and golden cane syrup were superior in attracting significant numbers of moths as compared to port wine and molasses. Fermented molasses was the least attractive among the four baits. Over 90% of the insects caught were noctuids with Graphania mutans and Tmetolophota spp. being the main noctuids captured (over 55%) in the four fermented sugar baits. Male and female G. mutans were equally attracted to the four sugar baits. A number of tortricid species were also trapped.     

温度对低光照下西番莲的生长、开花和营养吸收的影响

西番莲适于热带、亚热带种植,在低于0℃的温度下,大多数种类易遭受严重的冻害.在不同的温度状况下,各基因型的产果能力也不同.在海拔较高(2000米以上)的热带地区,紫果西番莲的产量最高,而黄果西番莲以及两个品种间的杂交种则较适于低海拔地种植.本文旨在报导温度对三个西番莲杂交种的生长、开花和营养吸收的影响.在澳大利亚Nambour,于低日射的冬季期间,在温室条件下种植西番莲植株.     

采后处理对荔枝果实贮藏腐烂的影响

1977—80年期间测定了不同杀真菌剂和化学药剂防治白地霉菌引起的荔枝冷藏腐烂病的效应。荔枝果实采后用0.1％氯化镍、0.1％硫酸镍、0.2％敌菌丹和0.1％克菌丹处理10分钟,获得了最佳效果。但在保持果实鲜艳色泽方面,仅0.1％氯化镍处理的效果最好,在3.88—5.55℃的冷藏条件下。装入穿礼聚乙烯袋中的荔枝处理果实可以贮藏6周。     

怎样在果树等“忌氯作物”上合理施用含氯化肥

含氯化肥系指含有氯离子(Cl~-)的一类化肥,如氯化钾、氯化铵。与硫酸钾、硫酸铵相比,这类化肥具有来源广、成本低的优点,因而普遍用作复混肥的钾源和氯源。但不同作物对氯离子的敏感程度不同,在施用时,应针对不同作物、气候及土壤条件合理施用。     

Microradiography of fossilized teeth

Microradiographic studies of fossil reptilian and amphibian teeth reveal an excellently preserved microstructure with little if any apparent mineralization except in the region of obvious fractures. X-ray diffraction has shown that the invading mineral near fractures is hematite, and x-ray spectroscopy has shown that relatively large amounts of yttrium are present.