Carbon dioxide sensitivity of mosquitoes infected with California encephalitis virus

Four species of mosquitoes became sensitive to carbon dioxide approximately 3 to 4 days after they received intrathoracic injectins of California encephalitis virus. Aedes melanimon and Aedes dorsalis infected orally with California encephalitis virus also became carbon dioxide-sensitive, but mosquitoes infected transovarially did not. Sensitivity to carbon dioxide was inhibited by antiserum to California encephalitis virus. To our knowledge this is the first report of carbon dioxide sensitivity induced in arthropods by a bunyavirus and the first demonstration of this phenomenon by an arbovirus in its proven vector.     

水疱性口炎病毒N基因原核表达载体的构建及表达

针对水疱性口炎病毒(VSV)N基因设计特异性引物,在引物中分别加入EcoR 和Xho 酶切位点。RT-PCR扩增后得到目的基因,将其克隆到表达载体pET30c,连接产物转化于DH5α菌株,在含Kan+的平板上37℃培养24h,然后挑取白色菌落,鉴定为阳性者,转化于BL21菌株,再经异丙基硫代-β-D-半乳糖苷(IPTG)诱导获得高效表达。表达融合蛋白分子质量为53ku(目的蛋白大约47ku),同预期蛋白大小相近。Westernblot检测表明,其能与本病毒阳性血清发生特异性反应,表达蛋白有望成为有价值的VSV诊断抗原。     

泰国虎纹蛙红腿病病原菌的分离鉴定及药敏试验

从患红腿病的濒死泰国虎纹蛙肝脏、心脏、腹水及病变腿部肌肉组织分离获得4株菌株（TW0701、TW0702、TW0703和TW0704）,根据细菌形态、培养特性、人工感染试验及API半自动微生物鉴定系统鉴定,确定4株分离株均为嗜水气单胞菌,且为泰国虎纹蛙红腿病的致病菌。以TW0701菌株为代表进行药敏试验,结果表明,该致病菌对头孢呋肟、先锋噻肟、先锋必、复达欣、氟苯尼考、菌必治、链霉素、卡那霉素、妥布霉素、头孢孟多、舒普深、磺胺二甲嘧啶、盐酸沙拉沙星、头孢西丁、环丙沙星、左氟沙星、恩诺沙星、氧氟沙星和磺胺六甲氧嘧啶（钠）等19种药物高度敏感,但对青霉素G、氨苄青霉素、苯唑青霉素、氧哌嗪青霉素、万古霉素、复方新诺明、阿莫西林、头孢噻吩、克林霉素、阿洛西林、头孢氨苄、新生霉素和头孢克洛等低度敏感或不敏感。     

Carbon dioxide and climate: the importance of realistic geography in estimating the transient temperature response

Results obtained from a detailed air-sea-ice climate model for an instantaneous increase in the atmospheric carbon dioxide content are used to estimate the transient surface temperature response for several time-dependent carbon dioxide increase scenarios. The inclusion of realistic variations of land fraction and ocean mixing with latitude is found to limit the applicability of steady- state simulations as approximate guides to the actual time-dependent temperature response, particularly when the regional response is considered.     

Brain lesions, obesity, and other disturbances in mice treated with monosodium glutamate

In newborn mice subcutaneous injectionis of monosodium glutamate induced acute neuronal necrosis in several regions of developing brain including the hypothanamus. As adults, treated animals showed stunted skeletal development, marked obesity, and female sterility. Pathological changes were also found in several organs associated with endocrine function. Studies of food consumption failed to demonstrate hyperphagia to explain the obesity. It is postulated that the aduls syndrome represents a multifacted nueroendocrine disturbance arising from the disruption of developing nueral centers concered in the mediation of endocrine function.     

Isolation of West Nile virus from mosquitoes, crows, and a Cooper's hawk in Connecticut

West Nile (WN) virus, a mosquito-transmitted virus native to Africa, Asia, and Europe, was isolated from two species of mosquitoes, Culex pipiens and Aedes vexans, and from brain tissues of 28 American crows, Corvus brachyrhynchos, and one Cooper's hawk, Accipiter cooperii, in Connecticut. A portion of the genome of virus isolates from four different hosts was sequenced and analyzed by comparative phylogenetic analysis. Our isolates from Connecticut were similar to one another and most closely related to two WN isolates from Romania (2.8 and 3.6 percent difference). If established in North America, WN virus will likely have severe effects on human health and on the health of populations of birds.     

山瑞鳖嗜水气单胞菌感染的诊断及防治

从患病山瑞鳖的肝脏、肺脏分离到1株细菌,对该菌的形态特征、生理生化进行分析,初步鉴定为嗜水气单胞菌。采用BioFosun-Ⅰ微生物鉴定系统对该菌进一步鉴定,结果显示为嗜水气单胞菌,可能性概率（PROB）为99%,相似性指数（SIM）和位距指数（DIS）分别为0.989和0.099。综合形态特征、生理生化特点及微生物鉴定系统鉴定结果,可将从发病山瑞鳖分离到的病原鉴定为嗜水气单胞菌。人工感染试验表明,该嗜水气单胞菌是引起山瑞鳖发病的病原且具有高度致死性;药敏试验结果则表明,该菌对头孢哌酮、阿米卡星、氧氟沙星、恩诺沙星4种药物敏感;选用头孢哌酮和恩诺沙星对病鳖进行治疗,可获得较好的治疗和控制效果,为今后山瑞鳖养殖生产中更有效地防制由该菌引起的疾病提供参考。     

纳米二氧化硅在涂料中的应用及其增强木材表面特性的构想

对纳米二氧化硅表面的改性方法及其与涂料作用的结合方式和机理做了详细概述。重点介绍了纳米二氧化硅在各种涂料中的应用现状,根据纳米二氧化硅能有效改善涂料的性能,提出了纳米二氧化硅增强木材表面涂饰特性的设想,最后就纳米二氧化硅涂料应用于木材表面改良展望了其发展前景。     

表面特性的构想

对纳米二氧化硅表面的改性方法及其与涂料作用的结合方式和机理做了详细概述。重点介绍了纳米二氧化硅在各种涂料中的应用现状,根据纳米二氧化硅能有效改善涂料的性能,提出了纳米二氧化硅增强木材表面涂饰特性的设想,最后就纳米二氧化硅涂料应用于木材表面改良展望了其发展前景。 参58     

岚皋魔芋软腐病病原细菌生物多样性研究

【目的】研究岚皋魔芋软腐病病原细菌生物多样性。【方法】采用组织分离法分离纯化魔芋软腐病球茎及叶柄中的致病菌,通过魔芋球茎、胡萝卜及马铃薯块的侵染试验初步确定其致病性,再利用魔芋球茎侵染致病及盆栽致病性试验确认其致病性;经菌落与细胞形态、生理生化特性及16SrRNA序列测定确定病原菌的类型。【结果】从魔芋软腐病球茎及叶柄中共分离获得16株细菌,侵染试验表明,其中CDS1-B1、CDS1-B2、CDS2-B1、CDS2-B2、CZS-B4和CZS-B6共6株细菌可使魔芋球茎表现软腐症状,并导致盆栽魔芋发病;6株细菌的菌落与细胞形态均存在差异;在魔芋、胡萝卜及马铃薯块上的侵染能力不同;16SrRNA序列分析表明,菌株CDS1-B1、CDS1-B2、CDS2-B1及CDS2-B2均与菊欧氏杆菌(Erwinia chrysanthemi)亲缘关系最近,菌株CZS-B4与菊欧文氏菌(Dickeya dadantii)亲缘关系最近,相似度为98.8%,菌株CZS-B6与菊果胶杆菌(Pectobacterium chrysanthemi)的相似度达99.9%。【结论】导致岚皋县魔芋软腐病的致病细菌存在生物多样性,其致病性也存在差异,其中新发现的魔芋软腐病原菌菊果胶杆菌(Pecto-bacterium chrysanthemi)致病性最强,菊欧氏杆菌(Erwinia chrysanthemi)和菊欧文氏菌(Dickeya dadantii)致病性较弱。     

北京市农田生态系统碳足迹及碳生态效率的年际变化研究

近年来,由于北京城市功能的疏解以及郊区城市化进程的加快,使北京市农田生态系统受到了较大的冲击。本文以北京农田生态系统作为研究对象,对2004—2012年农田生态系统的碳汇、碳源、碳足迹以及碳生态效率的年际变化进行了研究,以明确其在北京城市发展中的功能与地位,为北京市健康持续发展及产业布局提供理论依据。结果表明:北京农田生态系统碳汇总体呈增加趋势,年递增幅度为2.8%,年平均碳蓄积量为105.82 万t,决定其碳汇功能的主要因素是粮食作物中玉米与小麦的经济产量及种植面积。北京农田生态系统的年均碳排放量为27.6 万t,基本呈现逐年降低的趋势,年均递减1.3%,决定碳排放量的主要因素为农业化学品中氮素化肥的施用量。北京市农田生态系统年均碳足迹为5.71 hm2²,呈逐年降低的趋势,年递减率为5.5%,处于碳生态盈余状态,但是由于近年北京市耕地面积的减少,碳生态盈余量呈下降趋势;北京农田生态系统的碳生态效率较高,年均为3.854 kg C·kg^-1 CE,农业生产处于较高的持续状态。     

Carbon, carbides, and methane in an apollo 12 sample

Total carbon in the Apollo 12 sample 12023 fines was 110 micrograms per gram of sample with a carbon isotopic abundance delta(13)C (relative to the Pee Dee belemnite standard) of +12 per mil. Hydrolysis of the fines with deuterium chloride yielded undeuterated methane along with deuterated hydrocarbons, thus confirming the presence of 7 to 21 micrograms of carbon per gram of sample as carbide and about 2 micrograms of carbon per gram of sample as indigenous methane. After vacuum pyrolysis of the fines to 1100 degrees C the following gases were detected in the relative abundance: carbon monoxide carbon dioxide methane. Variations of the delta(13)C value with the pyrolysis temperature indicated the presence of carbon with more than one range of isotopic values. The observed delta(13)C value of +14 per mil for lunar carbide is much higher than that of carbide in meteorites. These results suggest that lunar carbide is either indigenous to the moon or a meteoritic contribution that has been highly fractionated isotopically.     

自然主义的哈尼稻作及其可持续发展

\t\t\t\t\t目的\t\t\t\t\t探究水稻秸秆的饲用特征对UV-B辐射的响应。\t\t\t\t\t\t\t\t\t\t\t\t\t方法\t\t\t\t\t通过大田原位模拟试验,以元阳梯田传统水稻品种白脚老粳为材料,研究不同强度UV-B辐射处理(0、2.5、5.0和7.5 kJ/m²)对水稻秸秆生长形态(茎秆长、茎粗和生物量)和饲用化学成分(粗纤维、粗脂肪、粗灰分、粗蛋白、中性洗涤纤维、酸性洗涤纤维、淀粉、可溶性糖和非蛋白氮)的影响,并分析秸秆的品质营养价值指数(秸秆的可吸收营养物质总量TDN、净能NE₁、秸秆干物质采食量DMI、可消化的干物质DDM和相对饲料价值RFV)。\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t结果\t\t\t\t\t随着UV-B辐射增强,水稻秸秆的长度和茎粗增加,生物量下降。不同UV-B辐射增强处理下,水稻秸秆的粗蛋白含量、粗纤维含量、粗脂肪含量、粗灰分含量和中性洗涤纤维含量没有显著的差异;非蛋白氮含量、淀粉含量和可溶性糖含量表现出单峰变化规律;酸性洗涤纤维含量在2.5 kJ/m² UV-B辐射处理时最低。2.5和5.0 kJ/m² UV-B辐射处理时,形态响应指数、饲用品质响应指数和综合响应指数较高;2.5 kJ/m² UV-B辐射处理时,秸秆的品质营养价值指数TDN、NE₁、DMI、DDM和RFV最高,分别为46.92 g/kg、5.01 MJ/kg、1.93 g/kg、56.05 g/kg和83.85%。\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t结论\t\t\t\t\t适当的UV-B辐射能提高水稻秸秆的饲用特征,UV-B辐射为2.5 kJ/m²时水稻秸秆饲用特征较好。\t\t\t\t\t\t\t\t\t     

植物对UV-B辐射的响应与调控机制

目的研究不同UV-B辐射处理对水稻不同生育时期(分蘖期、拔节期和抽穗期)叶片氮代谢及其产量的影响。方法以元阳梯田水稻品种白脚老粳为材料,大田原位种植,研究不同UV-B辐射强度(0、2.5、5.0和7.5 kJ/m²)对水稻各生育时期叶片氮代谢关键酶[硝酸还原酶(NR)、谷氨酰胺合成酶(GS)和谷氨酸合成酶(GOGAT)]活性、含氮物质(可溶性蛋白与总游离氨基酸)含量及产量构成指标(有效穗数、穗粒数、千粒质量、结实率及产量)的影响。结果与对照相比,2.5 kJ/m² UV-B辐射时水稻抽穗期GS活性、拔节期GOGAT活性、分蘖期和抽穗期总游离氨基酸含量显著提高(P<0.05);5.0 kJ/m² UV-B辐射时水稻分蘖期NR活性、各生育期GS和GOGAT酶活性、可溶性蛋白及游离氨基酸含量显著增加(P<0.05),拔节期NR活性显著降低(P<0.05);7.5 kJ/m² UV-B辐射时水稻各生育时期叶片的NR、GS与GOGAT活性、可溶性蛋白含量及总氨基酸含量均显著降低(P<0.05)。UV-B辐射增强抑制白脚老粳有效穗数、穗粒数、结实率和千粒质量,导致产量下降,7.5 kJ/m² UV-B辐射强度下产量下降幅度最大为22.8%。结论大田增强UV-B辐射对元阳梯田地方水稻品种叶片氮代谢影响有显著的“剂量+生育时期”效应,中低强度UV-B辐射对水稻氮代谢有促进作用,UV-B辐射强度为5.0 kJ/m²时最为显著,高强度UV-B辐射对水稻氮代谢有抑制作用。增强UV-B辐射导致水稻产量下降。     

高产玉米田土壤呼吸强度及其与碳、氮营养的关系

以松辽平原玉米带高产培育土壤与平产土壤(常规耕作土壤)为研究对象,研究了土壤呼吸强度的变化特征及其与土壤碳、氮营养的关系。结果表明:高产培育土壤基础呼吸强度增加;底物诱导呼吸强度则在高产、平产土壤上变化规律不明显,当葡萄糖浓度低于50 mg/kg时,随着葡萄糖浓度的增加,高产及平产土壤呼吸强度均迅速提高;呼吸商在不同地区高产、平产土壤的变化差异不同,呼吸商与土壤有机碳、全氮、碱解氮及碳氮比呈极显著负相关(P0.01)。反映了土壤呼吸强度与土壤碳氮营养的相互调节作用。因此在农业生产中适量施用有机物质既可以补充一定的营养物质,又可以提高土壤呼吸强度,提高微生物活性及其功能,改善土壤碳氮营养结构。     

Polysomes and protein synthesis in cells infected with a DNA virus

In HEp-2 cells infected with herpes simplex virus the rate of protein synthesis at first decline, is stimulated between 4 and 8 hours after infection, and progressively and irreversibly declines from 9 to 16 hours later. The increase and decrease in rates coincide with corresponding changes in the amounts of cytoplasmic polysomes and amounts of labeled amino acids in nascent peptides bound to polysomes. The data indicate that (i) early and late inhibition and intervening stimulation of protein synthesis are due to the corresponding breakdown and formation of polysomes, and (ii) the bulk of viral proteins is probably made on cytoplasmic polysomes.     

Silicone rubber: oxygen, carbon dioxide, and nitrous oxide measurement in gas mixtures

Pressure changes, arising from counter diffusion of gases through a sealed silicone rubber tube, may be used to measure tension of gases in a mixture. When the tube is initially filled with one of the gases, and the mixture surrounds it, the pressure rise is related to the tension of the remaining gas.