鸡新城疫病毒与大肠杆菌内毒素的相互作用

利用细胞培养、鸡胚及 8周龄幼鸡对鸡新城疫病毒 ( NDV)与大肠杆菌内毒素的相互作用进行了研究。这些相互作用通过在宿主系统中诱导产生的特异性或非特异性反应 ,以及在鸡胚和鸡体内产生的病毒滴度得到评价。1　大肠杆菌内毒素可导致活鸡法氏囊萎缩给鸡静脉注射大肠杆菌内毒素诱导产生的血液抗病毒活力成分称为干扰素 ,与在水泡性口炎病毒蚀斑减少试验中所检出的结果相同。因在鸡胚成纤维细胞 ( CEF)上 NDV蚀斑形成的数量没有发生变化 ,所以内毒素不对鸡胚成纤维细胞造成毒害 ,也不导致任何抗病毒效应。鸡群感染 NDV前 3d注射大肠杆菌…     

辽宁省气象灾害预警短信发布平台的设计与应用

为适应农村气象防灾减灾的新形势和新要求,建设一套集约化、易管理、节省资源、稳定性强的分布式气象灾害预警信息短信发布平台。其依托辽宁省气象局广域网,以SQL Server 2000为后台数据库支撑,实现辽宁省、市、县3级气象部门均能将气象灾害预警信息、决策气象信息服务中的实时信息(降水量资料、实况资料等)通过统一的绿色短信渠道灵活、直接、及时提供给当地政府和相关部门。     

棉铃虫APN基因家族系统进化与功能分析

氨肽酶N(APN)是锌金属蛋白酶M1家族的成员,鳞翅目昆虫中肠刷状缘膜囊泡(brush border membrane vesicles,BBMV)细胞膜上的APN不仅在蛋白消化吸收过程中起着重要的作用,而且是Bt的重要受体蛋白.本研究通过PCR技术克隆得到7条棉铃虫APN基因全长序列,HaAPN1～7(Genbank...     

Inert gases in lunar samples

Sample 10084,40 (fines, less than 1 millimeter) contains substantial amounts of the inert gases. Their concentrations are inversely proportional to particle size; hence the gases appear to be surface-correlated in the soil fragments. The most likely origin of the gas is solar wind or solar cosmic rays. Glass and feldspar are generally poorer in gas than lithic fragments. Ratios of elements in the sample differ significantly from solar values. Ratios of isotopes in the sample are similar to those in meteorites. Argon-40 appears to consist of a radiogenic and a surface-correlated component. An apparent potassium-argon age of 4.42(+0.24)(-0.28) billion years is calculated.     

Assessment of Sperm DNA Fragmentation in Stallion (Equus caballus) and Donkey (Equus asinus) Using the Sperm Chromatin Dispersion Test

Sperm DNA fragmentation (sDF) is an important parameter to assessing sperm quality. Information about sperm quality is not available for donkeys, especially in some breeds at risk of extinction. The objectives of this research were to test the four commercial variants of sperm chromatin dispersion test (SCD; sperm Halomax test), originally developed to assess sDF in boars, bulls, rams and stallions, in order to scrutinize their applicability in the study of sDF in a donkey breed at risk of extinction (Zamorano-Leonesa), for which there is no specific test available to analyze sperm at present. Only the SCD test, originally developed for stallions, produced stable and consistent results, and was deemed suitable to assess DNA fragmentation in sperm samples from donkeys. Image analysis was used to compare differences between the SCD methodology applied to stallion and donkey semen samples processed under the same experimental conditions. The extent of SCD in the SCD test was approximately 20% lower in donkey sperm than in stallion sperm. Yet, the ratio of chromatin sperm dispersion achieved in fragmented and unfragmented nuclei did not differ significantly between species. These data suggest that a similar protein depletion treatment can cause differences in protein removal in equivalent cells from different species and that sperm chromatin may be organized differently in stallions and donkeys.     

Impact of Ultra‐Rapid Freezing on the Motility,Morphology, Viability and Acrosome Integrity of Epididymal Cat Sperm Diluted in Sucrose‐Based Extenders

The objective of the present study was to investigate the influence of different sucrose‐based extenders on the motility, morphology, viability and acrosomal integrity of epididymal cat spermatozoa cryopreserved by ultra‐rapid freezing method. Nine cats were castrated, and collected semen was diluted 1 : 1 with Dulbecco`s phosphate‐buffered saline‐BSA1%‐based extender supplemented with different sucrose concentrations (0, 0.25, 0.4 and 0.6 m ). After ultra‐rapid freezing, samples were thawed and sperm motility, morphology, viability and acrosome status were assessed. At thawing, the number of progressively motile (p < 0.01) and morphologically normal (p < 0.01) sperm was higher in the sucrose‐supplemented groups than in the sucrose‐free group. Viability of spermatozoa cryopreserved without sucrose was significantly reduced. In extender supplemented with 0.4 m sucrose, spermatozoa viability showed higher values (57.0 ± 4.7; p < 0.01). No significant differences were detected among groups for sperm acrosome integrity. Results support that cat sperm survive after ultra‐rapid freezing using sucrose as a cryoprotectant, and the best results were achieved when 0.4 m of sucrose was used. This is the first report on sperm ultra‐rapid freezing of cat sperm and further studies on extenders, sperm management or cryovials should be carried out to improve sperm cryosurvival.     

A mammal survey of the Serra Jeci Mountain Range,Mozambique, with a review of records from northern Mozambique’s inselbergs

The mountains of northern Mozambique have remained poorly studied biologically until recent years with surveys covering a variety of taxonomic groups highlighting their biological and conservation value. Even so, the medium and large mammal fauna remains poorly known and to date no systematic mammal surveys have been published from any of Mozambique’s mountains. We present results of a medium and large mammal survey of Serra Jeci’s Mt Chitagal, Mt Sanga and the Njesi Plateau in Niassa, northern Mozambique; the first mammal diversity data collected from these isolated mountains. We recorded 27 mammal species, of which six represent range expansions; Sykes’s monkey (Cercophitecus mitis), Mozambique dwarf galago (Paragalago granti), Smith’s red rock hare (Pronolagus rupestris), lesser cane rat (Thryonomys gregorianus), rock hyrax (Procavia capensis) and African buffalo (Syncerus caffer). We also reviewed and collated records of medium and large mammals from previously published fieldwork on northern Mozambique’s mountains, amounting to a total of 34 large mammal species from seven montane areas, highlighting the lack of mammalian knowledge in Mozambique’s Afromontane habitats.     

不同处理方式的妃子笑荔枝花穗ARF基因家族的表达分析

生长素反应因子(ARF)是一类可以结合在生长素应答基因启动子部位的转录因子,在植物的生长发育中起着至关重要的作用。为了研究荔枝ARF基因在不同花穗处理方式的表达情况,进而挖掘花穗发育过程中起主要作用的ARF关键基因,本研究利用课题前期基于转录组数据库鉴定出的LcARF基因家族,通过对妃子笑荔枝花穗分别进行疏花和喷施烯效唑处理,利用荧光定量PCR(qRT-PCR)技术进一步研究LcARF基因家族在不同处理下的表达情况。结果表明：21 个荔枝ARF基因在疏花和烯效唑处理花穗发育过程中有明显不同的表达规律,且不同基因表达量有较大差异。因此推测,ARF家族成员在花穗发育过程中特定阶段起一定的作用,同时本研究也为深入探究ARF基因家族的功能奠定理论基础。     

油菜直播机旋切式微垄种床制备装置设计与试验

针对长江中下游油菜适播期持续干旱或降雨导致土壤含水率波动大影响油菜成苗的实际情况,探究油菜农机农艺融合模式,提出一种旋耕碎土、两侧开畦沟、厢面旋切微垄、微垄表面播种的油菜微垄直播工艺,设计一种油菜直播机旋切式微垄种床制备装置。根据油菜直播株行距配置、根系生长特点,结合垄作土壤水热特性,确定微垄几何尺寸;基于运动学解析腹板端点旋切土壤的运动规律和腹板滚动包络线,从结构角度定性分析被动旋转过程并确定回转半径、腹板数量、腹板顶角范围;利用DEM-MBD耦合仿真,进行单因素试验和正交旋转回归试验,从土壤角度定量研究了腹板数量、腹板顶角、旋切深度、前进速度对微垄成形的影响规律,并得到装置腹板数量分别为6和8的较优工作参数组合;田间试验使用Trimble TX8三维激光扫描仪重构装置作业后微垄厢面,与仿真结果进行对比分析。结果表明,腹板数量分别为6和8时较优工作参数组合为：腹板顶角、旋切深度、有效沟深分别为28.00°、100 mm、83.59 mm和26.50°、92 mm、64.26 mm,田间试验微垄沟深和微垄距平均值为103.08、85.16 mm和332.92、266.88 mm,与仿真...     

苦荆茶中多酚类物质的含量测定

应用比色法对苦荆茶(Ilex.sp)中总多酚类物质的含量进行了测定,发现了多酚类物质在不同等级和产地的茶叶中含量存在差异,嫩叶中含量明显高于老叶;在芽叶中多酚类物质含量竟高达9.39%左右,接近普通绿茶中茶多酚的含量,因而推测苦荆茶可能具有抗氧化、抗衰老和延年益寿的功效.