检索结果-南通市图书馆

Linking forest diversity and tree health： preliminary insights from a large-scale survey in Italy

Forest Ecosystems 2018年第2期5卷 151-161页

作者： Filippo Bussotti Matteo Feducci Giovanni Iacopetti Filomena Maggino Martina Pollastrini Federico selvi Department of Agri-Food Production and Environmental Sciences (DISPAA) University of Firenze Piazzale delle Cascine 18- 50144 Florence Italy Department of Statistical Sciences University La Sapienza P.le Aldo Moro 5 00185 Rome Italy

Forest health is currently assessed in Europe （ICP Forests monitoring program）. Crown defoliation and dieback, tree mortality, and pathogenic damage are the main aspects considered in tree health assessment. The worsening of environmental conditions （i.e., increase of temperature and drought events） may cause large-spatial scale tree mortality and forest decline. However, the role of stand features, including tree species assemblage and diversity as factors that modify environmental impacts, is poorly considered. The present contribution reanalyses the historical dataset of crown conditions in Italian forests from ] 997 to 2014 to identify ecological and structural factors that influence tree crown defoliation, highlighting in a special manner the role of tree diversity. The effects of tree diversity were explored using the entire data set through multivariate cluster analyses and on individual trees, analysing the influence of the neighbouring tree diversity and identity at the local （neighbour） level. Preliminary results suggest that each tree species shows a specific behaviour in relation to crown defoliation, and the distribution of crown defoliation across Italian forests reflects the distribution of the main forest types and their ecological equilibrium with the environment. The potentiality and the problems connected to the possible extension of this analysis at a more general level （European and North American） were discussed.

关键词： Cluster analysis Crown defoliation Forest structure ICP Forests Neighbouring trees Tree diversity Tree identity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cyclotriphosphazene Fibre Reinforced Poly(benzoxazine-co-ε-caprolactam) Nanocomposites for Flame Retardant Applications

引用

Chinese Journal of Polymer Science 2014年第8期32卷 1086-1098页

作者： M.selvi S.Devaraju K.Sethuraman R.Revathi M.Alagar Polymer Composite Lab Department of Chemical Engineering Anna University Next MEMS Lab School of Mechanical Engineering Pusan National University

Cyclophosphazene nanotube （PZT） incorporated poly（benzoxazine-co-g-caprolactam）（P（BZ-co-CPL）） nano- composites were developed for improving flame retardant properties. The effects of PZT on the flammability properties of P（BZ-co-CPL） matrix were evaluated through UL-94 flammability test and limiting oxygen index （LOI）. The UL-94 results of P（BZ-co-CPL）/PZT hybrid nanocomposites showed V-1 rating, whereas neat P（BZ-co-CPL） showed burning rating. The LOI values are increased from 25.4 to 31.4 for 1.5 wt% PZT incorporated P（BZ-co-CPL） nanocomposite systems. SEM was used to study the char morphology of P（BZ-co-CPL）/PZT after being exposed to UL-94 flammability test. Data from thermal studies indicate that the PZT incorporated P（BZ-co-CPL） systems possess better Tg and thermal degradation behavior when compared to the neat P（BZ-co-CPL）. The values of dielectric constant are decreased with increasing temperature. From the values, it is ascertained that the P（BZ-co-CPL）/PZT systems exhibit stable dielectric behavior with regard to variation in temperature. The TEM images ascertain the uniform dispersion of PZT in the P（BZ-co-CPL） matrix.

关键词： Polybenzoxazine Phosphazene Flame retardant Dielectric properties.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

In vitro anti-biofilm and anti-bacterial activity of Junceella juncea for its biomedical application

引用

Asian Pacific Journal of Tropical Biomedicine 2012年第12期2卷 930-935页

作者： P Kumar S Senthamil selvi M Govindaraju Department of Environmental Biotechnology Bharathidasan University Department of Plant Science Bharathidasan University

Objective:To investigate the anti-biofilm and anti-bacterial activity of Junceella juncea(***)against biofilm forming pathogenic ***:Gorgonians were extraeted with methanol and analysed with fourier transform infrared *** forming pathogens were identified by Congo red agar supplemented with sucrose.A quantitative spectrophotometric method was used to monitor in vitro biofilm reduction by microtitre plate ***-bacterial activity of methanolic gorgonian extract(MGE)was carried out by disc diffusion method followed by calculating the percentage of increase with crude methanol(CM).Results:The presence of active functional group was exemplified by FT-IR ***,black,crystalline colonies confirm the production of extracellular polymeric substances responsible for biofilm formation in Congo red *** exhibited potential anti-biofilm activity against all tested bacterial *** anti-bacterial activity of methanolic extract was comparably higher in Salmonella typhii followed by Escherichia colt,Vibrio cholerae and Shigella *** overall percentage of increase was higher by 50.2%to ***:To conclude,anti-biofilm and anti-bacterial efficacy of *** is impressive over biofilm producing pathogens and are good source for novel anti-bacterial compounds.

关键词： Junceella juncea Anti-biofilm Anti-bacterial FT-IR Congo red agar Microtitre plate assay

来源：

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

Efficacy of larvicidal and pupicidal activity of Catharanthus roseus aqueous and solvent extracts against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae)

引用

Asian Pacific Journal of Tropical Medicine 2013年第8期6卷 625-630页

作者： Selladurai Subarani selvi Sabhanayakam Chinnaperumal Kamaraj Gandhi Elango Mohamed Abdul Kadir Department of Zoology Annamalai University Post Graduate and Research Department of Zoology C. Abdul Hakeem College Department of Chemistry MSS Wake Board College

Objective: To investigate the larvicidal and pupicidal activities of aqueous, ethyl acetate and methanol extracts of Catharanthus roseus ( C. roseus ) against malaria and filariasis vectors. Methods: The larvicidal and pupicidal activities of C. roseus leaf extracts were tested against the fourth instar larvae and pupae of Anopheles stephensi ( An. stephensi ) and Culex quinquefasciatus ( Cx. quinquefasciatus ). The mortality was observed after 24 and 48 h post the treatment. The data were subjected to probit analysis to determine the lethal concentrations (LC 50 and LC 90 ) at which 50% and 90% of the treated larvae or pupae of the tested species were killed. Results: The larval and pupal mortality were observed after 24 and 48 h of exposure of aqueous, ethyl acetate and methanol extracts of C. roseus ; no mortality was observed in the control group. The LC 50 values against the fourth-instar larvae of An. stephensi were 68.62 and 72.04 mg/mL for the aqueous extract, 82.47 mg/mL for the ethyl acetate extract, and 78.80 and 86.64 mg/mL for the methanol extract, while the aqueous, ethyl acetate and methanol extracts had LC 50 values of 85.21, 76.84 and 94.20 mg/mL against the fourth-instar larvae of Cx. quinquefasciatus . The aqueous, ethyl acetate and methanol extracts had LC 50 values of 118.08, 182.47 and 143.80 mg/mL against the pupae of An. stephensi and 146.20, 226.84 and 156.62 mg/mL against the pupae of Cx. quinquefasciatus , respectively. Conclusions: The aqueous and methanol extracts of C. roseus leaves had an excellent potential to control the malarial vector An. stephensi and filariasis vector Cx. quinquefasciatus .

关键词： Catharanthus roseus Anopheles stephensi Culex quinquefasciatus Larvicidal activity Pupicidal activity Medicinal plant

来源：

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

Free radical scavenging potential of Lagenaria siceraria(Molina) Standl fruits extract

引用

Asian Pacific Journal of Tropical Medicine 2013年第1期6卷 20-26页

作者： Vijayakumar Mayakrishnan selvi Veluswamy Krishnakumari Shanmuga Sundaram Priya Kannappan Noorlidah Abdullah Institute of Biological Science Faculty of ScienceUniversity of MalayaKuala Lumpur-50603Malaysia Department of Biochemistry Kongunadu Arts and ScienceCoimbatore-641029TamilnaduIndia Department of Biochemistry.PSG college of Arts and Science Coimbatore-641029TamilnaduIndia

Objective:To elucidate free radical scavenging activity of ethanolic extract Lagenaria siceraria （***）（Molina） ***:The free radical scavenging activity of the L siceraria （Molina） fruit extract was assayed by usingα,α-diphenyl-β-picrylhydrazyl（DPPH）. 2,20-azinobis 3-ethyl henzothiazoline-6-sulfonate（ABTS）,FRAP,reducing power,chelating ability andβ-carotene bleaching ***:The IC50values of DPPH and ABTS radicalscavenging activity was found to be 1.95 mg/mL and 19 mg/mL,*** ferrous chelation assay,the percentage of inhibition was found to be 89.21%.The reducing power of ethanolic extract of L siceraria（Molina） fruit was 0.068 at 1 mg/mL and increased to 0.192 at 5 mg/mL Theβ-carotene linoleate bleaching assay was 46.7%at 5 mg/mL and antioxidant activity using FRAP at 0.305 for 1 mg/mL to 0.969 for 5 mg/mL Conclusions:The results indicate that L siceraria （Molina） fruit could be an important sources of natural radical scavengers.

关键词： Lagenaria siceraria Antioxidant DPPH ABTS Free radical

来源：

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

Comparison of contrast sensitivity and visual acuity between deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with keratoconus

引用

International Journal of Ophthalmology(English edition) 2012年第6期5卷 737-741页

作者： Mehmet Orcun Akdemir Baran Kandemir Isil Bahar Sayman Cem selvi OmerKamil Dogan Department of Ophthalmology School of Medicine Bulent Ecevit University Kartal Lutfi K1rdar Research and Education Hospital Darica Armedica Eye Hospital Kudret Eye Hospital

AIM: To evaluate postoperative visual acuity and contrast sensitivity results following deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in patients with keratoconus (KC). METHODS: All the patients’ records with KC who had PK or DALK surgery between May 2010 and May 2011 were retrospectively reviewed. Sixty patients who underwent successful corneal transplantation for KC: 30 eyes underwent DALK and 30 eyes underwent PK were included in this study. Preoperative and postoperative mean logarithm of the minimum angle of resolution (logMAR) uncorrected visual acuity (UCVA), logMAR best spectacle-corrected visual acuity (BSCVA) and intraocular pressure (IOP) were evaluated. Contrast sensitivity tests (CS) were done preoperative and 2 months after all sutures had removed. All surgeries were performed under regional anesthesia (retrobulbar anesthesia) by 1 surgeon (B.K.) who was experienced in penetrating and lamellar keratoplasty techniques. RESULTS: The mean age of the DALK group was 29.67±4.95 (range 18-40) years and the PK group was 28.7±3.53 (range 18-39) years. Preoperatively there was no significant difference in the logMAR UCVA, logMAR BSCVA and IOP between the DALK (1.281±0.56; 0.97±0.85; 12.07±2.12mmHg) and PK (1.34±0.21; 0.98±0.21; 13±2.12mmHg) groups. One-year after surgery there was no significant difference in the mean logMAR UCVA and IOP between the DALK (0.46±0.37; 11.73±2.1mmHg) and PK (0.38±0.21; 12±2.12mmHg) groups. The mean contrast sensitivity was evaluated by CC-100 Topcon LCD at 1.5, 2.52, 4.23, 7.10 and 11.91 cycles per degree (cs/deg) spatial frequencies before and 2 months after the all sutures had removed. CONCLUSION: All patients with keratoconus in both DALK and PK groups performed good visual function postoperatively. The mean contrast sensitivity increased considerably at all spatial frequencies compared with preoperative levels in the DALK and PK groups. The mean post-operative evaluation of contrast sensitivity me

关键词： contrast sensitivity keratoconus corneal transplantation

来源：

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

Co-administration of rlpaB domain of Shigella with rGroEL of s. Typhi enhances the immune responses and protective efficacy against Shigella infection

引用

Cellular & Molecular Immunology 2015年第6期12卷 757-767页

作者： Sekar Tamil selvi Chitradevi Gurpreet Kaur Sivaramakrishna Uppalapati Anandprakash Yadav Dependrapratap Singh1 Anju Bansal Division of Experimental Biology Defence Institute of Physiology and Allied Sciences Delhi India Division of Microbiology Defence Food Research Laboratory Mysore India Division of Immunomodulation Defence Institute of Physiology and Allied Sciences Delhi India

Shigella species cause severe bacillary dysentery in humans and are associated with high morbidity and mortality. The Invasion plasmid antigen （IpaB） protein, which is conserved across all Shigella spp., induces macrophage cell death and is required to invade host cells. The present study evaluates the immunogenicity and protective efficacy of the recombinant （r） domain region of IpaB （rlpaB） of S. flexneri, rlpaB was administered either alone or was co-administered with the rGroEL （heat shock protein 60） protein from S. Typhi as an adjuvant in a mouse model of intranasal immunization. The IpaB domain region （37 kDa） of S. flexneriwas amplified from an invasion plasmid, cloned, expressed in BL21 Escherichia colicells and purified. Immunization with the rlpaB domain alone stimulated both humoral and cell-mediated immune responses. Furthermore, robust antibody （IgG, IgA） and T-cell responses were induced when the rlpaB domain was co-administered with rGroEL. Antibody isotyping revealed higher IgG 1 and IgG2a antibody titers and increased interferon-gamma （IFN-γ） secretion in the co-administered group. Immunization of mice with the rlpaB domain alone protected 60%-70% of the mice from lethal infection by S. flexneri, S. boydiiand S. sonnei, whereas co-administration with rGroEL increased the protective efficacy to 80%-85%. Organ burden and histopathological studies also revealed a significant reduction in lung infection in the co-immunized mice compared with mice immunized with the rlpaB domain alone. This study emphasizes that the co-administration of the rlpaB domain and rGroEL protein improves immune responses in mice and increases protective efficacy against Shigella infection. This is also the first report to evaluate the potential of the GroEL （Hsp 60） protein of S. Typhi as an adjuvant molecule, thereby overcoming the need for commercial adjuvants.

关键词： GroEL heat shock protein IpaB Shigella S. Typhi

来源：

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

Influence of preoperative coronary collateral circulation on in-hospital mortality in patients undergoing coronary artery bypass graft surgery with intra-aortic balloon pump support

引用

Chinese Medical Journal 2014年第17期127卷 3077-3081页

作者： Hasan Gungor Cemil Zencir Abraham Samuel Babu Cagdas Akgullu Ufuk Eryilmaz All Zorlu Mithat selvi Sevil Onay Tunay Kurtoglu Department of Cardiology Adnan Menderes University Aydin Turkey Department of Physiotherapy School of Allied Health Sciences Manipal University Karnataka India Department of Cardiology Cumhuriyet University Sivas Turkey Department of Cardiovascular Surgery Adnan Menderes University Aydin Turkey

Background Outcomes in patients requiring coronary artery bypass graft （CABG） surgery have been improved with devices such as the intra-aortic balloon pump （IABP）.Good coronary collateral circulation （CCC） has been shown to reduce mortality in patients with coronary artery disease （CAD）.We aimed to investigate whether poor preoperative CCC grade is a predictor of in-hospital mortality in CABG surgery requiring IABP *** Fifty-five consecutive patients who were undergoing isolated first time on-pump CABG surgery with IABP support were enrolled into this study and CCC of those patients was *** Twenty-seven patients had poor CCC and 28 patients had good ***-hospital mortality rate in poor CCC group was significantly higher than good CCC group （14 （50％） vs.4 （13％）,P=0.013）.Preoperative hemoglobin level （OR：0.752; 95％ CI,0.571-0.991,P=0.043）,chronic obstructive pulmonary disease （OR：6.731; 95％ CI,1.159-39.085,P=0.034） and poor CCC grade （OR：5.750; 95％ CI,1.575-20.986,P=0.008） were associated with post-CABG in-hospital *** CCC grade （OR：4.853; 95％ CI,1.124-20.952,P=0.034） and preoperative hemoglobin level （OR：0.624; 95％ CI,0.476-0.954,P=0.026） were independent predictors of in-hospital mortality after *** Preoperative poor CCC and hemoglobin are predictors of in-hospital mortality after CABG with IABP support.

关键词： coronary collateral circulation coronary artery bypass graft surgery intra-aortic balloon pump in-hospital mortality

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Spectral Evidence for the One-Step Three-Electron Oxidation of Phenylsufinylacetic Acid and Oxalic Acid by Cr(VI)

引用

American Journal of Analytical Chemistry 2013年第10期4卷 20-29页

作者： Perumal Subramaniam Natesan Thamil selvi Department of Chemistry Govindammal Aditanar College for Women Tiruchendur India Research Department of Chemistry Aditanar College of Arts and Science Tiruchendur India

The co-oxidation of a mixture of phenylsulfinylacetic acid (PSAA) and oxalic acid (OxH2) by Cr(VI) in 20% acetonitrile-80% water (v/v) medium follows third order kinetics, first order, each with respect to PSAA, OxH2 and Cr(VI). The reaction involves nucleophilic attack of sulfur atom of PSAA on chromium of the oxidizing species, Cr(VI)-OxH2 to form a ternary complex, Cr(VI)-OxH2-PSAA followed by a one-step three-electron reduction of Cr(VI) to Cr(III) and simultaneous oxidation of both the substrates. The reaction is catalysed by Mn2+ ion while retarded by Al3+ ion. Electron releasing substituents in the meta- and para-positions of the phenyl ring of PSAA enhance the rate of co-oxidation while electron withdrawing substituents retards the reaction. The Hammett plots at different temperatures exhibit excellent correlation with negative ρ values. The reaction series obey isokinetic relationship and the observed isokinetic temperature is lying below the experimental range of temperature.

关键词： Phenylsulfinylacetic Acid Oxalic Acid Co-Oxidation Nucleophilic Attack of Sulfur Three-Electron Transfer Substituent Effect

来源：

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

A Novel Approach for a Two Area Load Frequency Control in a Competitive Electricity Market Adopting Unscheduled Interchange Price

引用

Circuits and Systems 2016年第7期7卷 1155-1166页

作者： Murugesan Bhavani Kamatchi selvi Ravi Durga Department of Electrical and Electronics Engineering Anna University Regional Campus Madurai Madurai India Department of Electrical and Electronics Engineering Thiagarajar College of Engineering Madurai India

This paper proposes a novel price based load frequency control scheme for a two area system, using an Unscheduled Interchange (UI) price signal, which is ideal and suitable for electricity market. The Government of India has introduced Availability Based Tariff (ABT) structure with an intention of ensuring grid security and to regulate grid indiscipline through Central Electricity Regulatory Commission Regulation. After the introduction of this regulation, the over or under injection by the generating companies (GENCOs) during off peak or peak hours are demoralized and the frequency is maintained at the nominal value. In this paper, the GENCOs instead of reacting to this price signal manually, an automated mode of frequency control is deployed in each area using UI price signal to achieve fast response to load change. The Distribution Company (DISCO) Participation Matrix (DPM) has also been employed in this work to relate the scenario under deregulation of electricity market. The proposed scheme has been verified for different cases by simulating it on a two area system, each having four GENCOs and one DISCO in MATLAB/SIMULINK environment. From the results, it is clearly observed that if the proposed method is employed by all GENCOs, it will certainly enhance the control of system frequency and at the same time throw down the UI liability of market participants. It also ensures that the GENCOs and DISCOs strictly adhere to the bilateral contract following the DISCO participation matrix.

关键词： Deregulated Electricity Market Bilateral Contract Unscheduled Interchange Contract

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：