新型紫外探测器及其应用

综述了我所研制的新型紫外探测器的工作原理、结构设计。介绍了这类具有极高灵敏度和超快时间响应探测器的主要技术性能及其在高技术武器装备和民用市场的潜在应用。     

Accumulation of dead cells from contact killing facilitates coexistence in bacterial biofilms

Bacterial communities are governed by a wide variety of social interactions, some of which are antagonistic with potential significance for bacterial warfare. Several antagonistic mechanisms, such as killing via the type VI secretion system (T6SS), require killer cells to directly contact target cells. The T6SS is hypothesized to be a highly potent weapon, capable of facilitating the invasion and defence of bacterial populations. However, we find that the efficacy of contact killing is severely limited by the material consequences of cell death. Through experiments with Vibrio cholerae strains that kill via the T6SS, we show that dead cell debris quickly accumulates at the interface that forms between competing strains, preventing physical contact and thus preventing killing. While previous experiments have shown that T6SS killing can reduce a population of target cells by as much as 10⁶-fold, we find that, as a result of the formation of dead cell debris barriers, the impact of contact killing depends sensitively on the initial concentration of killer cells. Killer cells are incapable of invading or eliminating competitors on a community level. Instead, bacterial warfare itself can facilitate coexistence between nominally antagonistic strains. While a variety of defensive strategies against microbial warfare exist, the material consequences of cell death provide target cells with their first line of defence.     

战争条件下的经济对抗研究

战争条件下的经济对抗,对战争的取胜具有十分重要的保障和促进作用。探讨了现代战争条件下实施经济对抗所必须研究的经济对抗样式、经济对抗技巧和经济对抗原则,总结了战争条件下经济对抗的"四种样式""四种原则"和"四种策略"。     

半夏软腐病内生拮抗放线菌的分离与鉴定

针对半夏生产过程中软腐病废水普遍和危害严重的现状,从7个半夏主产区的半夏植株上分离到47个内生放线菌,通过平板和组培苗拮抗活性筛选获得两个具有较强活性的菌株07JX3-2和07JX3-7,经形态、培养特征和生理生化实验鉴定,初步确定两个分离物均属于链霉菌属(streptomyces),至于其所在种有待进一步鉴定。两个拮抗菌株的获得为半夏软腐病的生物防治研究和应用奠定了基础。     

关于对当前营养问题的探讨

人们对食物由“量”的满足转向“质”的重视,渴望食以健为先。而有些人由原来渴望“三高”食品变成了要求“三低一高”食品而走进了食品营养的误区。按照营养学理论“营养”和“营养素”是两个概念。营养素之间也有相互作用和相互制约关系即营养素之间的转化作用、协同作用、拮抗作用。     

Discourses of the wound and desire for the Other: remembrances of the Katyń massacre and the Smoleńsk crash

ABSTRACT

We investigate the commemorative debate in Polish newspapers about how the Katyń massacre and the presidential plane crash near Smoleńsk, Russia, should be remembered. We demonstrate that a psychoanalytic discursive analysis elucidates the insistence on remembering past wounds, nationalist politics of victimhood, and the difficulties in reaching rapprochement in intercultural relations. To this end, we analyze the commemorative debates in two main Polish newspapers and a news magazine. We argue that an emotive discourse of “Katyń as a wound” yearns for a therapeutic healing of the rifts in Polish national mythology and postcommunist identity. This discourse revolves around a demand for recognition from the Russian Other of a wounded subject by employing evocative metonymies and transposing logics of equivalence and difference.     

葡萄采后病害生防制剂用拮抗酵母的筛选

本研究通过对比5种拮抗酵母在抑制葡萄采后病害中的效果,以及在正常葡萄表面的生长适应性,从中筛选出适合开发成牛防制剂的种类.结果表明:罗伦隐球酵母和季也蒙假丝酵母的抑菌效果较好,从生长适应性方面比较,季也蒙假丝酵母最适合开发成生防制剂.     

Effects of ferulic acid and some of its microbial metabolic products on radicle growth of cucumber

An initial survey of the effects of aqueous solutions of ferulic acid and three of its microbial metabolic products at pH 4.5, 6.0, and 7.5 was determined on radicle growth of 11 crop species in Petri dishes. These bioassays indicated that cucumber, ladino clover, lettuce, mung bean, and wheat were inhibited by ferulic, caffeic, protocatechuic, and/or vanillic acids and that the magnitude of inhibition varied with concentration (0–2 mM), phenolic acid, and pH of the initial solution. The pH values of the initial solutions changed considerably when added to the Petri dishes containing filter paper and seeds. The final pH values after 48 hr were 6.6, 6.8, and 7.1, respectively, for the initial 4.5, 6.0, and 7.5 pH solutions. The amounts of the phenolic acids in the Petri dishes declined rapidly over the 48 hr of the bioassay, and the rate of phenolic acid decline was species specific. Cucumber was subsequently chosen as the bioassay species for further study. MES buffer was used to stabilize the pH of the phenolic acid solutions which ranged between 5.5 and 5.8 for all subsequent studies. Inhibition of radicle growth declined in a curvilinear manner over the 0–2 mM concentration range. At 0.125 and 0.25 mM concentrations of ferulic acid, radicle growth of cucumber was inhibited 7 and 14%, respectively. A variety of microbial metabolic products of ferulic acid was identified in the Petri dishes and tested for toxicity. Only vanillic acid was as inhibitory as ferulic acid. The remaining phenolic acids were less inhibitory to noninhibitory. When mixtures of phenolic acids were tested, individual components were antagonistic to each other in the inhibition of cucumber radicle growth. Depending on the initial total concentration of the mixture, effects ranged from 5 to 35% lower than the sum of the inhibition of each phenolic acid tested separately. Implications of these findings to germination bioassays are discussed.Paper No. 9000 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, North Carolina. Mention of trade or company names does not constitute a guarantee or warranty of the product by the North Carolina Agricultural Research Service and does not imply its approval to the exclusion of other products that may be suitable.     

金属化合物在PP膨胀阻燃体系中的研究

探讨了几种金属化合物对PP膨胀阻燃体系的影响,通过锥形量热仪分析了体系的阻燃性,SEM观察燃烧后材料的成炭情况。结果表明,ZB、ZEO、MgO能起到协效作用,成炭较好,而CuCl不但不能起到协效作用反而破坏了炭层的质量,呈对抗性。