潢川方言中一种特殊的“V+不完+的+V”格式

"V+不完+的+V"格式为潢川方言的一种特殊表达格式,通过与普通话中近义结构的对比,我们发现其语表、语里具有特殊性和限制性,这也决定了其语用价值的不可替代性。我们认为"V+不完+的+V"结构是一种特殊的动词复写形式,可以看作是一个虚拟让步复句的紧缩形式,也可以看作是移位、省略后的动词拷贝结构。     

基于小波变换的语音信号去噪

利用小波的时频域局部化特性,解决语音信号的去噪问题。文中给出了语音信号的小波去噪算法,并基于不同的阈值选取,提出了采用适合于语音信号的浮动阈值,实验表明去噪效果好,提高了语音信号的识别率。     

核盘菌对几种杀菌剂的敏感性研究

为了选择防治菌核病的有效药剂,采用FAO推荐的菌落直径法研究了常用杀菌剂对核盘菌敏感性的差异。结果表明:山西五寨菌株WZ2对腐霉利、多菌灵、菌核净、福美双、乙霉威、乙烯菌核利高度敏感(EC50在0.117 0~4.965 4μg.mL-1之间);对异菌脲中度敏感(EC50为5.069 0μg.mL-1);对代森锰锌和百菌清最不敏感(EC50为20.760 0,32.107 6μg.mL-1)。内蒙古菌株NM15和NM17均对腐霉利、多菌灵、菌核净、福美双、乙烯菌核利高度敏感(EC50在0.064 0~3.059 0μg.mL-1);对乙霉威、异菌脲中度敏感(EC50为7.330 7~13.823 4μg.mL-1之间);对代森锰锌最不敏感(EC50分别为37.645 3,42.303 0μg.mL-1)。另外,菌株NM15对百菌清高度敏感(EC50为2.104 8μg.mL-1),而NM17则对百菌清中度敏感(EC50为11.777 9μg.mL-1)。并且这三个菌株对腐霉利、百菌清的敏感性差异较大,而对其他药剂的敏感性差异不大。     

3,5-二硝基水杨酸法测定椰子纳塔发酵液中总糖含量研究

建立了椰子纳塔发酵液中总糖含量的测定方法.探索了吸收光谱、显色剂用量、显色时间、HCI浓度等测试条件.结果表明,波长550 nm处溶液的吸光度与葡萄糖含量有良好的线性关系,线性范围为0.2～11.0 mg/mL,R=0.9994;最佳显色剂量为2 mL.最佳显色时间为2 min,最佳水解总糖的HCI浓度为3 mol/L,样品平均回收率为100.08%(RSD=1.38%,n=5).说明该方法重复性好,可作为常规分析方法使用.     

马铃薯晚疫病菌基因文库的构建

用酶一氯化苄法制备高分子量晚疫病菌总ＤＮＡ,通过Ｓａｕ３Ａ部分酶切并纯化后得到１５－２５ｋｂ的酶切片段,并以具有广寄主范围的柯斯质粒ＰＬＡ２９１７为载体,用Ｔ４ＤＮＡ连接酶连成为重组ＤＮＡ,包装到入噬菌体颗粒中,转染受体菌Ｅ．ｃｏｌｉＳ１７－１。利用四环素和卡那霉素抗性来筛选鉴定重组子,得到１０６５６个重组子,这些重组子群即为晚疫病菌的基因组文库。     

不同套种作物对宽叶羌活生长的影响

［目的］研究不同套种作物对宽叶羌活生长的影响,为羌活栽培技术的研究提供科学依据。［方法］分别将羌活与蚕豆套种、羌活与小麦套种、羌活与油菜套种,并观察不同套种田羌活根部性状、叶部性状及生物量性状;测定试验地土壤中各养分含量的变化。［结果］蚕豆、小麦、油菜对套种羌活的基本苗、出叶数、侧根数没有显著影响;蚕豆茬口促进羌活根、叶片、茎的生长及生物量的增加作用明显高于小麦田和油菜田的促进作用;蚕豆、小麦、油菜茬口的全氮、全磷、全钾、有机质和pH值在生长季变化较小,速效养分普遍下降,其中,蚕豆茬下降明显,尤以速效氮下降最明显。［结论］ 小麦茬口有利于促进羌活根的生长,蚕豆茬口有利于促进羌活叶的生长。     

Pathogenic 'Bison-type' Mycobacterium avium subspecies paratuberculosis genotype characterized from riverine buffalo (Bubalus bubalis) in North India

Despite low per-animal productivity of ruminants in developing countries, Johne's disease has not been investigated in buffaloes, which are primarily found in these countries. This is due to lack of expertise, diagnostic kits and priority to production diseases like Johne's disease. Presence of pathogenic Mycobacterium avium subspecies paratuberculosis (Map) was investigated by screening of target tissues (mesenteric lymph nodes and large intestine) by culture and IS 900 PCR, in 50 sacrificed buffaloes. Indigenous ELISA kit originally developed for goats and sheep was standardized in buffaloes and used to estimate sero-presence of Map in 167 serum samples representing population of buffaloes in Agra region of North India. In culture, 48.0% buffaloes were positive from 50 tissues each from mesenteric lymph nodes (34.0%) and large intestine (36.0%). IS 900 PCR was standardized using specific primers (150 C and 921) and 229 bp-amplified product was characteristic for Map. Of the 25 mesenteric lymph nodes, 40.0% were positive in IS 900 PCR. Genomic DNA from Map cultures was successfully amplified from all the 24 isolates (100.0%). Map was further genotyped as 'Bison type' using IS 1311 PCR-REA. Culture of tissues showed high presence of Map in target tissues, despite high culling rate in buffalos in view of high demand of buffalo meat. Specific tissue-PCR provided rapid confirmation of Map infection in sacrificed buffaloes. In tissue-PCR, all the cultures were positive as compared to 40.0% detected directly from tissues. ELISA kit using indigenous protoplasmic antigen was highly sensitive as compared to commercial antigen in detecting Map infection therefore, could be used as 'Herd Screening Test' in buffaloes against Johne's disease. This pilot study first time reports a highly pathogenic 'Bison-type' genotype of M. avium subspecies paratuberculosis from the riverine buffaloes (Bubalus bubalis) of Agra region in North India.     

Characterization of shiga toxin-producing Escherichia coli strains isolated from calves in Poland

Fecal samples from 67 3–5-months-old calves with diarrhea were screened for the presence of shiga toxin-producing Escherichia coli (STEC). Several accessory virulence factors genes were also tested. Among 192 E.coli isolates tested, 15 (7.6%) were found to harbour the shiga toxin 1 or 2 (stx1 or stx2) genes. The stx2-carrying samples were further subtyped by PCR for the stx2c, stx2d, and stx2e toxin variants. It was shown that stx2-positive bacteria mainly possessed the stx2c shiga toxin type gene. The enterohemolysin (hlyA) and intimin (eae) genes were found in seven (46.7%) STEC strains whereas the cytotoxic necrotizin factor 1 and 2 or the P fimbrial genes were detected in two isolates only. This study confirmed that calves are a reservoir of STEC strains (with all pathogenicity genes) that may be virulent for humans.     

SA、MeJA、ACC和苹果轮纹病病原菌诱导湖北海棠MhWRKYl基因的表达

【目的】从湖北海棠叶片中克隆MhWRKY1转录因子的全长cDNA序列,分析该基因在各种组织中(叶、茎、根)的表达特性,并分析SA、MeJA、ACC在叶、茎、根中诱导MhWRKY1基因的表达模式以及苹果轮纹病病原菌诱导条件下湖北海棠叶片中该基因的表达特性。【方法】利用电子克隆技术和RT-PCR验证相结合的方法,从SA诱导的湖北海棠全长cDNA文库中,克隆MhWRKY1转录因子的全长序列;利用生物信息学的方法对其进行结构和功能的初步分析;利用实时荧光定量RT-PCR技术分析该基因在不同组织中的表达以及在SA、MeJA、ACC和苹果轮纹病病原菌诱导下的表达特性。【结果】克隆了MhWRKY1基因的全长cDNA序列为1 338 bp,GenBank数据库登录号为FJ598139。生物信息学分析表明,该基因最大开放阅读框为993 bp,编码330个氨基酸。推导的氨基酸序列与杨树WRKY26、杨树WRKY20、大豆WRKY,马铃薯WRKY2、烟草WRKY、拟南芥WRKY7、水稻WRKY53的同源性分别为68%、68%、66%、60%,59%,49%和43%。该转录因子含有1个WRKY结构域,其N端含有1个WRKYGQK结构...     

Cartographic Procedure for the Analysis of Aeolian Erosion Hazard in Natural Parks (Central System,Spain)

Cartographic analysis of the hazard of erosion is a useful tool for the planning and management of natural parks, helping to establish measures for protection and correction. Such parks, which offer spectacular landscape views and natural beauty, must be conserved with all their resources. Accordingly, park managers must have the cartographic tools for hazard planning, which is necessary for the rational and sustainable handling of human activities and the establishment of preventive and corrective measures. The present work describes a cartographic procedure using GIS that determines the risk of aeolian erosion. The method was applied to two protected natural parks in the central mountain system in Spain. This cartographic method revealed a weak risk of hazard of erosion in low‐lying areas or valley floors, with increasing risk in areas of deflation. These areas were explored by mapping geomorphological domains and slopes, characterising different surficial deposits: colluvium, piedmonts, debris cone, alluvial fans and river terraces. Aeolian erosion on cultivated surfaces with gentle slopes was observed to be low, but in sectors with little agricultural activity and undulated reliefs, the hazard of erosion is important owing to the high analytical and textural erodibility and scant vegetation cover of these sectors. These parameters were studied on the basis of the mapping of soils and soil profiles. Additionally, the cartography of vegetation and the wind index in the cartographic procedure allowed for the different degrees of aeolian erosion to be better quantified. Copyright © 2012 John Wiley & Sons, Ltd.