新中国成立60年来我国兽医防疫科技事业成就辉煌

回顾了新中国成立60年来,我国兽医防疫科技水平逐步提高,应对突发新的重大动物传染病的快速反应和疾病预防控制能力显著增强,消灭或有效控制了一些长期危害我国的重大动物传染病,兽用疫苗研究开发能力显著增强,取得丰硕成果,动物防控体系和人员队伍进一步健全完备,总结了60年来我国兽医科技事业的辉煌成就。     

Molecular epidemiology of Cryptosporidium subtypes in cattle in England

Samples of Cryptosporidium spp., collected in a cross-sectional study of calves (median age 26 days) from 41 farms in Cheshire, UK, underwent molecular typing. The aim was to determine naturally occurring species/genotypes and to investigate transmission pathways within a local area. Of 60 positive samples, 54 were sequenced at an 18S rRNA locus and 51 were typed at a GP60 locus. C. parvum was identified in 50 samples, three cases were C. bovis and one was Cryptosporidium deer-like genotype. Six GP60 subgenotypes were identified. One subgenotype (IIaA15G2R1) was highly prevalent throughout the study area. A single subgenotype was identified on 20/22 farms. Two subgenotypes were found on 2/22 farms. The spatial scan statistic detected a cluster of subgenotype IIaA15G2R1 comprising seven farms. This suggests local transmission of the parasite between farms. As most of the isolates detected were the potentially zoonotic C. parvum allele IIa, intervention strategies should be considered to reduce the threat to public health. Biosecurity measures may reduce transmission between farms and result in lower levels of environmental contamination.     

60Co-γ射线对萝卜种子发芽率及幼苗生长的影响

用不同剂量60Co-γ射线对萝卜种子进行辐射,观测其对种子发芽率和幼苗生长的影响。结果表明：其发芽率、芽长和根长与辐射剂量均呈正相关,说明在该实验辐射范围内对萝卜种子有刺激生长的作用,在20Gy-60Gy有利于萝卜种子发芽,而在60Gy和150Gy时有利于萝卜种子的生长。     

钴60辐射红掌组培材料的实验初报

用60Co 0.5-6 5Gy剂量辐射处理红掌6个品种的不定芽和愈伤组织材料,并进行组培试验,结果表明辐射愈强,参试材料受抑制程度愈大;不同红掌品种对辐射的敏感性不同;初步看出60Co对不定芽半致死剂量为30-40Gy,对愈伤组织半致死剂量为10-20Gy。     

60Co辐射对绿豆主要农艺性状影响及特异突变体创制

辐射诱变是作物育种行之有效的途径之一,但绿豆诱变育种研究相对落后。用300、400、500、600、700Gy 5个剂量的⁶⁰Co辐射处理籽粒大小不同的冀绿10号、冀绿15和V1128 3个品种的干籽粒种子,分析后代出苗率和主要农艺性状的变异情况,并对后代材料进行突变体选择。结果表明,不同辐射剂量⁶⁰Co对不同籽粒大小的绿豆品种有不同的辐射效果,其中,对大、中籽粒品种冀绿10号和冀绿15的出苗有明显的抑制作用,而对小籽粒品种V1128的出苗有明显的促进作用;高剂量辐射对绿豆后代营养体性状中主茎分枝数影响最大,使单株荚数和产量有显著增加的趋势,但对荚长和单荚粒数有一定的抑制作用;通过后代连续选择,获得了无分枝、雄性不育及荚型特异等稳定遗传的变异材料。可为绿豆辐射育种提供理论依据,创新的变异材料可供今后遗传研究及育种利用。     

基于扩展光学模型的电磁信号传播系统设计与实现

电磁信号传播系统的建模在复杂环境下有十分重要的意义，并且对模拟系统的准确性和快速性有一定的要求。本文基于扩展光学模型，以Java为平台开发语言，以射线追踪为核心算法，实现基于扩展光学模型的电磁信号传播系统的设计。通过与AREPS（高级折射效应预测系统）比较，证明本系统建模的准确性和很快的速度响应。