室外虾池笼养拟穴青蟹（Scylla paramamosain）的存活、蜕壳与生长

本文介绍了在对虾养殖池中笼养青蟹的研究结果。养殖试验历时60 d,以存活率、蜕壳率、甲长增长率、甲宽增长率和增肉系数为指标参数,比较了不同材质、容积和放置层次的养殖容器对笼养青蟹存活、蜕壳与生长的影响。结果表明：在水温25～30℃、盐度13～20、 pH7.8～8.3条件下,笼养青蟹的存活率为（59.85±9.50）%、蜕壳率为（40.69±5.90）%、甲长增长率为107.73%、甲宽增长率为89.39%、增肉系数为286.11%、肥满度＞1。养殖容器的材质、容积和放置层次对笼养效果有影响：胶绳网箱明显优于（ P〈0.05）塑料箱;容积10 L组与6 L组、18 L组相比养殖效果最佳,差异显著（ P〈0.05）, S组略优于B组,差异不明显（ P＞0.05）;第二层（中层）笼箱与第三层（底层）、第一层（表层）相比,笼养效果最佳,差异极为显著（P〈0.01）,第三层（底层）笼箱略优于第一层（表层）,但差异不明显（P＞0.05）。研究结果显示了在对虾养殖池内实施笼养青蟹方式的可行性。     

降雨条件下黏性土坡微结构动态环境能场分析

【目的】研究降雨条件下黏性土坡位移场、应变场、微结构动态环境能场的变化及对土坡稳定性的影响。【方法】通过室内土坡模型试验,用读数显微镜观测降雨前后土坡内45个测点的位移,特意选择并全程观测斜坡面(1个)、坡脚(2个)、坡底(1个)的4个测点的位移,研究侧向位移和竖向位移随时间的变化,利用反分析方法分析土坡的位移场与应变场的变化,从宏观、中观、微观角度上分析黏性土坡微结构动态环境能场及外部环境条件变化与其内在介质环境变化之间的关系。【结果】降雨条件下坡顶和坡脚处土体的损伤程度较大,最大竖向位移发生在坡脚处;用常规方法分析土坡变形时会低估瞬时变形而夸大固结变形;由斜坡面、坡脚和坡底的蠕变曲线可见,降雨初期的瞬时竖向位移和侧向位移增长较快,但随着降雨时间的延长,土坡微结构受到损伤,竖向位移和侧向位移的增长变慢,最后趋于稳定。【结论】降雨引发的土坡滑移大多数是瞬时的,土坡的蠕变既是土体损伤的过程,也是土坡微结构能量耗散的过程。因降雨劈裂力的作用,在坡顶及斜坡面上会出现裂缝,而斜坡面和坡脚是最容易诱发险情的部位。     

职业技能鉴定中的题库建设和命题技术研究

以化学检验工职业技能鉴定为例,对职业技能鉴定题库建设和试题编码、命题格式和命题要求等命题技术进行了系统的分析研究,提出了在合理制定鉴定要素细目表编码基础上,根据职业技能鉴定要素表命题,按照理论知识鉴定要素细目表和技能操作鉴定要素细目表中的代码进行全代码编码的编码方法,十分便于电脑随机抽取组合试卷。     

基于MODIS NDVI的京津风沙源工程治理区荒漠化动态监测

以MODIS植被指数产品为数据源,利用归一化植被指数(NDVI)进行京津风沙源工程治理区荒漠化程度划分,得出2000年、2004年、2008年荒漠化等级分布图,在此基础上对研究区不同等级荒漠化进行对比分析。结果表明:京津风沙源工程治理区荒漠化程度总体上呈现减少趋势;荒漠化转移方向主要为严重荒漠化→重度荒漠化→中度荒漠化→轻度荒漠化→非荒漠化。     

Genetic Transformation of Rice with Pi-d2 Gene Enhances Resistance to Rice Blast Fungus Magnaporthe oryzae

The gene Pi-d2, conferring gene-for-gene resistance to the Chinese blast strain ZB15, was isolated from a rice variety (Digu) by the map-based cloning strategy. Here, we constructed a control plasmid pZH01-pi-d2tp309 (pZH01-tp309) and three different expression constructs, pCB-Pi-d25.3kb (pCB5.3kb), pCB-Pi-d26.3kb (pCB6.3kb) and pZH01-Pi-d22.72kb (pZH01-2.72kb) of Pi-d2, driven by Pi-d2 gene's own promoter or CaMV35S promoter. These constructs were separately introduced into japonica rice varieties Lijiangxintuanhegu, Taipei 309, Nipponbare and Zhonghua 9 through Agrobacterium- mediated transformation. A total of 150 transgenic rice plants were obtained from the regenerated calli selected on hygromycin. PCR, RT-PCR and Southern-blotting assay showed that the gene of interest had been integrated into rice genome and stably inherited. Thirty-five transgenic lines independently derived from T1 progeny were inoculated with the rice blast strain ZB15. Transformants exhibited resistance to rice blast at various levels. The lesions on the transgenic plant leaves were less severe than those on the controls and the resistance level of transgenic plants harboring the gene of interest from three vectors had no difference. The own promoter of Pi-d2, about 2.2 kb or 3.2 kb, had the similar promoter function as CaMV35S. Field evaluation for three successive years supported the results of artificial trial, and some lines with high resistance to rice leaf blast and neck blast were obtained.     

冬虫夏草感染蝙蝠蛾幼虫研究进展

随着冬虫夏草资源的日趋枯竭,冬虫夏草人工繁育研究逐渐成为菌物学家和昆虫学家研究的热点,而冬虫夏草人工繁育研究的核心内容是冬虫夏草菌感染蝙蝠蛾幼虫研究.为此,就感染幼虫的龄期、感染方法、感染过程等方面进行了综述.     

对我国毛皮用绵、山羊产业发展的思考

在全面分析我国现有10个毛皮用绵、山羊品种所处生态环境和种质特性基础上,就当前存在的主要问题提出发展我国毛皮用羊的思考与建议,对我国毛皮羊的保种选育提高和更充分发挥其生产潜力具有一定的参考价值.     

Expression of SARS-CoV functional receptor angiotensin-converting enzyme 2 in nephritic epithelium of primates

AIM: To investigate the expression of angiotensin-converting enzyme 2 (ACE2) in nephritic epithelium of primates. METHODS: The expression of ACE2 in Vero E6 cells was detected by the techniques of RT-PCR and immunocytochemistry (ICC) techniques. The distribution of ACE2 protein in kidney tissues of two Rhesus monkeys and two normal human cases was observed by immunohistochemistry (IHC) techniques. RESULTS: Vero E6 cells were found to express both ACE2 mRNA and protein. ACE2 protein was mainly located in epithelium of proximal tubules of Rhesus monkey and human kidney. CONCLUSION: The expression of ACE2 in epithelium of primate kidney may provide the condition for SARS-CoV entry, which may be one of the reasons for inducing renal damage in SARS patients.     

罗汉果组培苗在湖南湘西地区的引种研究

通过对罗汉果组培苗"农青2号"进行大田种植观察分析,探讨其在湖南湘西地区的生态适应性,为推广种植罗汉果提供依据。结果表明:该品种8月上旬初花,花期110 d左右,有效授粉期25~30 d,10月下旬成熟,每667 m2产果12 986.1个,大中果率达60%,其中丰产园大中果率在80%以上,甜甙V含量0.16%,无明显病虫害,适合在湖南湘西地区推广种植。     

InDel and SNP Markers and Their Applications in Map-based Cloning of Rice Genes

High-density markers are necessary for map-based cloning of dca genes, but the currently available markers are not satisfactory enough. InDel (insertion-deletion length polymorphism) and SNP (single nucleotide polymorphism) are the new generation of molecular markers and can basically meet the need of fine mapping. InDel and SNP markers can be developed through bioinformatics. These markers are valuable markers with the characters of low cost, high specificity and stability. This article introduced the methods for designing InDel and SNP markers, taking the mapping of a dce rolled leaf gene as an example. In addition, some key factors in improving the design efficiency were also discussed.