Spatial variability of common carp populations in relation to lake morphology and physicochemical parameters in the upper Midwest United States

Weber MJ, Brown ML, Willis DW. Spatial variability of common carp populations in relation to lake morphology and physicochemical parameters in the upper Midwest United States.
Ecology of Freshwater Fish 2010: 19: 555–565. © 2010 John Wiley & Sons A/S Abstract – Common carp (Cyprinus carpio) is a widespread invasive species that is tolerant of a wide range of environmental conditions. Despite the circumpolar distribution of the species, limited information is available describing factors related to spatial variation in population characteristics. Eighty‐four lakes and impoundments in the upper Midwest United States were sampled to investigate the relationships of common carp relative abundance with size structure, condition and growth rates. We also investigated abiotic factors (lake morphology, physical solids and water quality) that may broadly influence common carp populations. Common carp size structure and condition were inversely related to relative abundance. Common carp relative abundance increased and size structure shifted to smaller individuals with increased lake depth, whereas lake surface area, watershed:surface area ratio and physical solids were also important in explaining common carp abundance and size structure. Common carp condition was best explained by water quality parameters and increased with metrics of lake productivity. We conclude that knowledge of factors associated with variation in common carp populations among lakes provides insights into the autecology and broad provisions for management of this generalist invasive species.     

KHAPLI在小麦抗病育种中的利用

普通小麦(Triticum aeslivum,2n=6x=42)与二粒小麦Khapli (T. dicoccum,2n=4x=28)杂交,因普通小麦品种不同,传递给杂交种的基因数也不同。抗贵白4号、16号和20号小种的两个显性抗白粉病基因,容易遗传给六倍体小麦遗传背景。抗贵白64号小种的可能有1个隐性基因,较难遗传给普通小麦的杂种后代。     

A 9-year monitoring study of diseases on potato seed tubers imported to Israel

Potato seed tubers are imported annually to Israel from northern Europe. Although the seed is registered as certified, a survey carried out over a 9-year period indicated that most lots were affected by latent or active bacterial and fungal infections. Latent infection byErwinia carotovora subsp.atroseptica, the causal agent of blackleg, at a level of 10³ cells/g peel, was present in 30% of the lots in most years. Black scurf caused byRhizoctonia solani was present in 20–70% of the imported lots, with a moderate to high level of infection in all years except 1985. In contrast, although many lots were affected by powdery scab, common scab, and Fusarium dry rot in most years, disease incidence within lots was generally low. The gangrene pathogen (Phoma exigua) was rarely detected. The survey findings are of marked importance, due to the extensive use of soil fumigation in Israeli agriculture.     

Synthesis and insecticidal activity of benzoheterocyclic analogues of N'-benzoyl-N-(tert-butyl)benzohydrazide: Part 3. Modification of N-tert-butylhydrazine moiety

Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species.     

奶牛常用饲料干物质和淀粉瘤胃降解规律的研究

以3头安装有永久性瘤胃瘘管的泌乳前期荷斯坦奶牛为试验动物，在精粗比为55：45的日粮条件下，采用Insacco法测定了奶牛常用饲料瘤胃内干物质和淀粉的降解规律。试验结果表明。不同饲料干物质和淀粉的降解率不同。能量饲料中，麸皮干物质和淀粉的瘤胃降解率高于玉米：蛋白质饲料中，干物质和淀粉的降解率由高到低顺序依次是豆粕〉胡麻饼〉棉粕：常用粗料中，玉米青贮干物质和淀粉的降解率均高于青干草。     

在市场经济条件下建设共同富裕的和谐社会

建设共同富裕的和谐社会，是发展社会主义市场经济的根本目的，也是区别于资本主义市场经济的重要标志；既要运用市场经济建立起增进社会财富、克服平均主义的竞争机制；又要运用市场经济建立起先富带后富，消除两极分化实现社会公平的激励机制和调节机制；也就是要在市场经济条件下建茈起实现共同富裕、促进社会和谐的有效机制。     

管道线路工程中的水工保护

水工保护是管道建设中的一个重要环节，但由于对其认识和重视程度不够，每年汛期，管道都会不同程度地出现一些水害问题，分析了管道遭受水害的一些基本现象及原因，提出了一些常用的水工保护措施。     

软土地基钻孔灌注桩施工质量通病与防治

软土地基钻孔灌注桩工程施工质量通病主要有：缩径、断桩、桩顶冒水、桩身孔洞、钢筋笼＂上浮＂、＂烂桩头＂、桩孔坍孔、孔位倾斜等。就其形成原因逐一进行剖析,并提出了相应的防治措施。     

儒家思想与宪政主义试说

宪政精神与儒家礼治思想有着相通之处,通过讨论,指出对分权形式的制度安排不能做绝对化的理解,进而从制度的演化生成论出发,提出以宪政主义替代自由主义来实现政治改革在理论和实践上必要性与优越性。     

空肠弯曲菌共同抗原单克隆抗体的研制及其在细菌检验中的应用 Ⅱ.杂交瘤细胞株的建立及特性鉴定

应用B-淋巴细胞杂交瘤技术,建立了5株稳定分泌抗空肠弯曲菌共同抗原(CA)单克隆抗体(McAb)的杂交瘤细胞株(4A7,9D6、9C2、11A1、11D4)。在5株杂交瘤分泌的McAb中,有4株(4A7、9D6、11A1、11D4)针对CA中的耐热抗原成分,对其中4A7、9D6两株分泌的McAb进行免疫印迹分析表明,其与CA中大约为7.7×104u的蛋白移行带出现特异反应;一株(9C2)针对CA中的不耐热抗原成分。对杂交瘤细胞的核型分析表明,其染色体数在93-108之间。体外传代4个月,仍保持稳定分泌抗体的特性。这种McAb具有较强的特异性,除与幽门弯曲菌出现弱阳性反应外,与参试的其它31种非弯曲菌属的细菌均为阴性反应。对不同地区、不同来源的516株空肠弯曲菌的鉴定表明,制备的McAb与现有空肠弯曲菌均出现阳性反应,与常规鉴定法的符合率为100％。