检索结果-南通市图书馆

Identifying PCR primers to facilitate molecular phylogenetics in Caddisflies(Trichoptera)

在线全文

学校读者我要写书评

暂无评论

Zoological systematics 2015年第4期40卷 459-469页

作者： Bonnie s.mcCullagh scott A.Wissinger Jeffrey m.marcus Department of Biological sciences University of Manitoba Departments of Biology and Environmental science Allegheny College Rocky mountain Biological Laboratory

The molecular phylogenetics of the Lepidoptera （butterflies and moths） is well studied, but that of Trichoptera （caddisflies）, the sister clade of Lepidoptera, is less studied. The PCR primer libraries developed for lepidopteran phylogenetics might work in Trichoptera. DNA from 8 caddisfly species （Asynarchus nigriculus （Banks, 1908）, Grammotaulius lorettae Denning, 1941, Hesperophylax occidentalis （Banks, 1908）, Limnephilus externus Hagen, 1861, Limnephilus picturatus mcLachlan, 1875, Limnephilus secludens Banks, 1914, Limnephilus sublunatus Provancher, 1877 and Agrypnia deflata （milne, 1931）） was used to screen for amplification. 107 primer pairs for 45 nuclear and 3 mitochondrial genes were tested. Primers for 1 new gene （40s ribosomalprotein $2 （RPs2）） and 8 genes previously used in Trichopteran phylogenetics were recovered （16s rRNA, 18s rRNA, carbamoyl-phosphate synthetase （CAD）, cytoehrome oxidase I （CO1）, cytochrome oxidase 11 （COIl）, elongation factor-1 alpha （EF-1 alpha）, isoeitrate dehydrogenase （IDH）, and RNA polymerase-II （POL-I1））. New primer pairs extended the genomic region sampled for many genes. Evolution rates among loci varied by 2 orders of magnitude. Differences among evolution rates and modes of inheritance offer flexible tools for resolving phylogenetic questions and examining genome evolution in the Trichoptera. screening libraries of PCR primers is a useful approach for identifying PCR primers in related taxa with limited molecular genetic resources.

关键词： Trichoptera molecular phylogenetics m.s.ic genome evolution rates ofsequence evolution PCR primer library.

Performance Evaluation of 800 kV Porcelain multicone Type Insulators Under Heavy Rain

在线全文

学校读者我要写书评

暂无评论

高电压技术 2008年第12期34卷 2552-2557页

作者： Orsino Oliveira Filho Darcy R. mello Jose A. Cardoso Rogerio m. de Azevedo sylvia G. Carvalho Waldenir A. s. Cruz CEPEL Electric Power Research Center Av. Olinda s/n Adrian6polis Zip Code 26053-121 Nova Iguacu RJ Brazil FURNAs Rua Real Grandeza 219 Zip Code 22283-900 Rio de Janeiro RJ Brazil

An 800 kV electric power substation can have more than one hundred of porcelain multicone type insulators supporting busbar *** or more sections in series,having middle and end fittings,compose these *** process can cause degradation of the cement used in this type of insulator and this fact can affect its dielectric performance under heavy *** paper presents results of an investigation based on power frequency high voltage tests performed on 800 kV porcelain multicone type insulators,removed from.s.rvice after having operated for more than 20 years,as well a non-used one that had been stored on site for long *** insulators were tested in different arrangements:each section at a time and the two sections assembled in series,as actually used insulator *** tests were carried out under artificial rain ranging from 1 mm/min to 5 mm/*** results have confirmed a reduction of up to 30% in the insulator power frequency flashover voltage under 5 mm/min rain conditions and gave important information to the utility about radial cracks that were observed in many insulators and about the discharge mechanisms along the insulators under rain.

关键词：叠装式瓷绝缘子性能评估大雨条件电功率

A field study of a roof bolter canopy air curtain(2nd generation)for respirable coal mine dust control

在线全文

学校读者我要写书评

暂无评论

International Journal of mining science and Technology 2019年第5期29卷 711-720页

作者： W.R.Reed s.Klima m.s.ahan G.J.H.Ross K.singh R.Cross T.Grounds CDC NIOsH Pittsburgh Mining Research DivisionPittsburghPA 15236USA Fletcher&Co. HuntingtonWV 25705USA Prairie state Generating Company LLC Lively GroveIL 62257USA

A 2nd generation roof bolter canopy air curtain(CAC)design was tested by National Institute for Occupational safety and Health(NIOsH)at a midwestern underground coal *** the study,the roof bolter never operated downwind of the continuous *** a combination of personal Data Rams(pDR)and gravimetric samplers,the dust control efficiency of the roof bolter CAC was *** evaluation was determined using three methods:(1)comparing roof bolter operator concentrations underneath the CAC to roof bolter concentrations outside the CAC,(2)comparing roof bolter operator concentrations underneath the CAC to the concentrations at the rear of the bolter,and finally,(3)using the gravimetric data directly underneath the CAC to correct roof bolter operator concentrations underneath the CAC and comparing them to the concentrations at the rear of the *** 1 dust control efficiencies ranged from 53.9%to 60.4%.method 2 efficiencies ranged from 150.5%to 52.2%,and method 3 efficiencies ranged from 40.7%to 91%.Reasons for negative and low dust control efficiencies are provided in this paper and include:incorrect sampling locations,large distance between CAC and operator,and contamination of intake air from line *** dust concentrations encountered during the testing made it difficult to discern whether differences in concentrations were due to the CAC or due to variances inherent in experimental dust ***,the analyses,especially the method 3 analysis,show that the CAC can be an effective dust control device.

关键词： Coal Roof bolter Respirable dust Underground mining

mechanical behavior of organo-modified Indian bentonite nanoclay fiber-reinforced plastic nanocomposites

在线全文

学校读者我要写书评

暂无评论

Frontiers of materials science 2013年第4期7卷 396-404页

作者： N. RAGHAVENDRA H. N. NARAsImHA mURTHY m. KRIsHNA K. R. VIsHNU mAHEsH R. sRIDHAR s. FIRDOsH G. ANGADI s. C. sHARmA Center for manufacturing and Research Technology Utilization R. V. College Campus Bangalore 560059 Karnataka India Department of mechanical Engineering R. V. College of Engineering Bangalore 560059 Karnataka India Department of Chem.s.ry ACS College of Engineering Bangalore 560074 Karnataka India Tumkur University Tumkur 572103 Karnataka India

The aim of the research was to examine the influence of organo-modified Indian bentonite （IB） nanoclay dispersed in vinyisster on the mechanical properties of nanoclaylvinylesterlglass nanocomposRes. Nanoclay was organically modified using cationic surfactant hexadecyltrimethylammonium bromide （HDTmA-Br） by cation exchange method and dispersed in vinylester using ultrasonication and twin screw extrusion. XRD of nanoclaylvinylester revealed exfoliaUon at 4 wt.% nanoclay indicating uniform dispersion in the polymer. DsC results showed improvement in glass transition temperature by 22.3% in 4 wt.% nanoclaylvinylester/glass when compared with that of vinylester/glass. Nanoclay/vinylester/glass with 4 wt,% nanoclay showed 29.23%, 23.84% and 60.87% improvement in ultimate tensile strength （UTs）, fiexural strength （Fs） and interlaminar shear strength （ILss） respectively when compared with those of vinylester! glass. The mode of tensile failure examined by sEm.s.owed no agglomeration of nanoclay in 4 wt.% nanoclayNinylester/glass specimens.

关键词： Indian bentonite (IB) ultrasonication twin-screw extrusion mechanical property

Distribution,structure and biosynthetic gene families of(1,3;1,4)-β-glucan in sorghum bicolor

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2015年第4期57卷 429-445页

作者： Riksfardini A.Ermawar Helen m.Collins Caitlin s.Byrt Natalie s.Betts marilyn Henderson Neil J.shirley Julian schwerdt Jelle Lahnstein Geoffrey B.Fincher Rachel A.Burton Australian Research Council Centre of Excellence in Plant Cell Walls University of Adelaide

In cereals, the presence of soluble polysaccharides including（1,3;1,4）-b-glucan has downstream implications for human health, animal feed and biofuel applications. sorghum bicolor（L.） moench is a versatile crop, but there are limited reports regarding the content of such soluble ***, the amount of（1,3;1,4）-b-glucan present in sorghum tissues was measured using a megazyme assay. Very low amounts were present in the grain, ranging from 0.16%–0.27%（w/w）, while there was a greater quantity in vegetative tissues at 0.12–1.71%（w/w）. The fine structure of（1,3;1,4）-b-glucan, as denoted by the ratio of cellotriosyl and cellotetraosyl residues,was assessed by high performance liquid chromatography（HPLC） and ranged from 2.6–3：1 in the grain, while ratios in vegetative tissues were lower at 2.1–2.6：1. The distribution of（1,3;1,4）-b-glucan was examined using a specific antibody and observed with fl uorescence and transm.s.ion electron microscopy. micrographs showed a variable distribution of（1,3;1,4）-b-glucan in fl uenced by temporal and spatial factors. The sorghum orthologs of genes implicated in the synthesis of（1,3;1,4）-b-glucan in other cereals, such as the Cellulose synthase-like（Csl） F and H gene families were de *** pro filing of these genes across sorghum tissues was carried out using real-time quantitative polymerase chain reaction, indicating that, as in other cereals, Csl F6 transcripts dominated.

关键词： Cellulose synthase-like genes cell wall composition mixed-linkage glucan grain sorghum

Natural sediment at a dam and its inorganic materials as adsorbents of praseodymium(Pr(Ⅲ))

在线全文

学校读者我要写书评

暂无评论

International Journal of sediment Research 2023年第4期38卷 566-575页

作者： melania Jiménez-Reyes Jaime Jiménez-Becerril marcos solache-Ríos Perla Tatiana Almazán-sánchez Departamento de Química Instituto Nacional de Investigaciones Nucleares Carretera México-Toluca S/N CONACy T-Instituto Nacional de Investigaciones Nucleares

The sediment deposited behind a dam(Ds) and its inorganic materials(Im-Ds) were characterized and used for the removal of praseodymium(Pr) from aqueous solutions. Quartz, albite, and kaolinite were found in the sediment by X-ray diffraction. Kinetic data fit well to a pseudo second-order model, the equilibrium time for Ds and Im-Ds was 2 h and 3 min, respectively, and the adsorption capacity was higher for Pr/Ds(qe= 4.91 mg/g) than for Pr/Im-Ds(qe= 3.01 mg/g) in these conditions. Pr/Ds and Pr/Im-Ds data isotherms were in agreement with the Langmuir-Freundlich model and the maximum adsorption capacities were 4.95 and 4.01 mg/g, respectively. Both processes are exothermic(enthalpy change, ΔH0=-22.8 and-21.8 k J/mol for Ds and Im-Ds, respectively), the increase of the randomness is small, and the feasibility and spontaneity are low. Praseodymium was desorbed by ethylenediaminetetraacetic acid disodium(EDTA-Na2), sodium chloride, nitric, citric, and humic acids solutions, and one hundred percent of praseodymium was desorbed by the EDTA-Na2solution. The Pr2(EDTA)3(praseodymium ethylenediaminetetraacetate) complex was completely desorbed from both materials(Ds and Im-Ds). Distribution coefficients(KD) depend upon praseodymium concentration,temperature, p H, and the kind of adsorbent. Chemical reactions of praseodymium with kaolinite and iron minerals could explain the adsorption.

关键词： Praseodymium sediment Adsorption process parameters Desorption

Availability and Use of Willow species in Representative Cold Desert Areas of Northwestern Himalaya,India

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of mountain science 2013年第3期10卷 472-481页

作者： Yashwant s.RAWAT Colin s.EVERsON Centre for Water Resources Research School of AgriculturalEarth and Environmental SciencesUniversity of KwaZuluNatal

Willow species(salix fragilis *** *** L.) are important elements of cold desert agroforestry systems in the Lahaul valley,northwestern *** ability to grow through shoot-cuttings plantations under extreme and xeric climatic conditions of cold deserts,makes them ecologically suited and socially accepted for forestry *** species in cold deserts may combat desertification and can thrive well in these areas as compared to any other *** fragilis *** *** *** under cultivation in the Lahaul ***,*** is widely cultivated under the agroforestry and plantation forestry *** the Lahaul valley,willow species are used as subsistence resources and for socio-religious *** present study was carried out to examine the vegetation analysis,density,diversity and distribution of willow species,present status and potential willow plantation sites and *** results of present study revealed that a higher species density was recorded at middle altitude villages(Jahlma-3,000 m asl and Hinsa-2,700 m asl),except,a higher density of *** was at Khoksar(3,200 m asl) in plantation forestry on south-facing *** forests,*** was planted mainly along the water channels,resulted a low *** shrubby willow species occurred naturally in the entire Lahaul valley up to an altitude of 3,850 m asl.81% of households felt the scarcity of willow trees,whereas,19% of households were satisfied with the willow trees they *** majority of willow species were planted in middle altitudes on privately owned irrigated *** was rated m.s. potential prospective willow planting site by the *** size of land-holdings was one of the main constraints for establishing a large number of willow *** aspects of willow species need to be investigated to encourage the farmers to plant more willows further.

关键词：北喜马拉雅沙漠地区物种可用性农林业系统海拔高度印度高密度

Differences in sensitivity of native and exotic fish species to changes in river temperature

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2011年第6期57卷 852-862页

作者： R.s.E.W. LEUVEN A.J. HENDRIKs m.A.J. HUIJBREGTs H.J.R. LENDERs J. mATTHEWs VAN DER VELDE Radboud University Nijmegen Institute for Water and Wetland Research Department of Environmental Science Heyendaal- seweg 135 NL-6525 AJ Nijmegen The Netherlands Radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 NL-2300 RA Leiden The Netherlands

This paper describes the effects that temperature changes in the Rhine river distributaries have on native and exotic fish diversity. site-specific potentially affected fractions (PAFs) of the regional fish species pool were derived using species sensitivity distributions (ssDs) for water temperature. The number of fish species in the river distributaries has changed remarkably over the last century. The number of native rheophilous species declined up until 1980 due to anthropogenic disturbances such as commercial fishing, river regulation, migration barriers, habitat deterioration and water pollution. In spite of progress in river rehabilitation, the native rheophilous fish fauna has only partially recovered thus far. The total number of species has strongly increased due to the appearance of more exotic species. After the opening of the Rhine-main-Danube waterway in 1992, many fish species originating from the Ponto-Caspian area colonized the Rhine basin. The yearly minimum and maximum river temperatures at Lobith have increased by circa 40C over the period 1908-2010. Exotic species show lower PAFs than native species at both ends of the temperature range. The interspecific variation in the temperature tolerance of exotic fish species was found to be large. Using temporal trends in river temperature allowed past predictions of PAFs to demonstrate that the increase in maximum river temperature negatively affected a higher percentage of native fish species than exotic species. Our results support the hypothesis that alterations of the river Rhine’s temperature regime caused by thermal pollution and global warming limit the full recovery of native fish fauna and facilitate the establishment of exotic species which thereby increases competition between native and exotic species. Thermal refuges are important for the survival of native fish species under extreme summer or winter temperature conditions.

关键词：敏感性差异水温度鱼种池鱼类多样性莱茵河流域外来物种 PAFs 温度变化

systematic mutational analysis of epitope-grafted ED3 immunogenicity reveals a DENV3-DENV4 bi-serospecific ED3 mutant

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical medicine 2022年第2期15卷 63-70,I0001-I0004页

作者： mamtaz sultana Nazmul Hasan mamunur R.mahib mohammad m.Islam Department of Biochem.s.ry and molecular Biology University of ChittagongChittagong-4331Bangladesh

Objective:To identify the residue determinants of the serospecificity and sero-cross-reactivity of dengue virus(DENV)envelope protein domain 3(ED3),which contains two major putative epitopes of ***:We constructed ED3 from DENV3(3ED3)and DENV4(4ED3),and six epitope-grafted variants,where we transferred epitope 1(L304I,K305D,V309m,and s310A)and/or epitope 2(D383N,K384s,K387T,and N389H)of 4ED3 onto 3ED3 and *** albino mice aged 3-4 weeks were immunized against wildtype and epitope-grafted ED3 variants and anti-ED3 IgG antibody responses were determined using ***:mouse immunization using 3ED3 and 4ED3 generated serotype-specific antisera,as ***,m.s. epitope-grafted ED3s produced antisera serospecific to the template ED3 with little or no cross-recognition of ED3 of the serotype from which the epitopes were *** indicated that a mere grafting of the epitope was not sufficient to transfer serospecificity,contrary to our ***,one epitope-grafted ED3 mutant,where epitope 1 of 3ED3 was grafted onto 4ED3(4ED3^(epi1)),generated antisera that was serospecific to both 4ED3 and ***:The 4ED3^(epi1)is a chimeric ED3 that produces antisera possessing serospecificity to both 3ED3 and 4ED3 onto a common 4ED3 *** 4ED3^(epi1),therefore,provides a unique tool for analyzing serospecificity and sero-cross-reactivity in *** believe that chimeric ED3 may provide a template for future recombinant ED3 possessing serospecificity of multiple DENVs onto a single scaffold and may pave a way developing tri-and/or tetravalent anti-DENV antisera.

关键词： Dengue virus serospecificity sero-cross-recognition Anti-ED3 antibodies Epitope-grafting Chimeric ED3