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Progress in Natural Science:Materials International 2017年第3期27卷 303-310页

作者： b.Parveen M.Hassan S.Atiq S.Riaz S.Naseem M.Asif Toseef Materials Growth and Simulation Laboratory Department of PhysicsUniversity of the Punjab Centre of Excellence in Solid State Physics University of the Punjab Department of Physics Govt. Islamia College

SnS is a promising Ⅳ-Ⅵ semiconductor,which is very less explored for diluted magnetic semiconducting and dielectric *** this study,the Ni doping(xNi=0-10mol%) effects on SnS host lattice were investigated.A simple and low cost co-precipitation technique was employed to grow Ni doped SnS *** X-ray diffraction confirmed single phase orthorhombic structure with a nano-crystalline nature that was further verified through the surface structure observed by scanning electron *** edge x-ray absorption fine structure spectroscopy revealed a shift in the Ni absorption edge towards higher energy,depicting the formation of Ni+3oxidation *** impedance measurements,in the frequency range 1 kHz to 20 MHz,depict that owing to the excellent sensitivity to the electromagnetic radiations at the low energy,the Ni doped SnS finds potential applications in various energy related *** sample magnetometer measurements have elucidated room temperature ferromagnetism,which depicts potential memory device applications.

关键词： Diluted magnetic semiconductors Room temperature ferromagnetism Near edge x-ray absorption fine structure spectroscopy Dielectric properties Co-precipitation method

Epidemiology of antibiotic resistance in burkina Faso

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Asian Pacific Journal of Tropical Medicine 2008年第2期1卷 1-6页

作者： Simpore J Zeba b Karou D Ilboudo D Pignatelli S Nacoulma OG Musumeci S Saint Camille Medical Centre(SCMC) OuagadougouBurkina Faso University of Ouagadougou Burkina Faso University of Rome "Tor Vergata" RomeItaly Department of Pharmacology Gynecology and ObstetricsPediatricsUniversity of Sassari and Institute of Biomolecular ChemistryNational Research Council(CNR)Li Punti(SS)Italy

burkina Faso(West Africa) is a tropical country with a high incidence of infectious *** uncontrolled use of antibiotics against bacterial pathogens has given rise to the emergence of antibiotic resistance in this *** aims of this study were;i) to determine the prevalences of the most important pathogenic bacteria isolated in the town of Ouagadougou;ii) to identify the bacterial species which have acquired resistance as a result of antibiotic selection;iii) to compare antibiotic-resistances of Escherichia coli isolated from stool culture in the present study with results obtained in 2002 from strains collected in the same structure in burkina Faso;iv) to determine the trend of antibiotic resistance in burkina Faso in order to give local advice on the most appropriate empiric antibiotic *** thousand two hundred and sixty four samples of blood,stools, urine,sputum,pus and vaginal secretion were collected and analyzed in Saint Camille Medical Center(SCMC) laboratory from May 2001 to May *** of the 6264 samples tested no pathogen was identified in 1583(25.31%),whilst 4681(74.73%) were positive with the incidence of the microrganisms isolated being as follows;Escherichia coli 1291(27.6%),Staphylococcus aureus 922(19.7%),Salmonella spp 561(12. 0%),Streptococcus spp 499(10.7%),Klebsiella spp 359(7.7%),Shigella spp(6.3%),Acinetobacter spp 266(5.7%) and others 783(16.7%).Among the isolated pathogens,the highest resistance was found to amoxicillin:Proteus spp 95,6%,Escherichia coli 78,2%,Salmonella spp 62,2%,Shigella spp 73,4% and Klebsiella spp 89,9%,followed by resistance to ampicillin and *** the prevalence of antibiotic resistance of Escherichia cob’from stool cultures isolated during 1999-2000 to that of 2001-2006, a significant reduction was found which could be due to the improved use of antibiotics in recent *** reduced antibiotic-resistance observed in pathogens isolated in burkina Faso during this study as compa

关键词： Escherichia coli antibiotic-resistance burkina Faso

Seasonal Inhomogeneity of Soot Particles over the Central Indo-Gangetic Plains,India:Influence of Meteorology

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Journal of Meteorological Research 2015年第6期29卷 935-949页

作者： SINGH b.P. TIWARI S. HOPKE Philip K. SINGH R.S. bISHT D.S. SRIVASTAVA A.K. SINGH R.K. DUMKA U.C. SINGH A.K. RAI b.N. SRIVASTAVA Manoj K. Department of Geophysics Banaras Hindu University Indian Institute of Tropical Meteorology(New Delhi branch) Clarkson University Department of Chemical Engineering Banaras Hindu University Aryabhatta Research Institute of Observational Sciences Department of Physics Banaras Hindu University

black carbon（bC） particles play a unique and important role in earth’s climate *** was measured（in-situ） in the central part of the Indo-Gangetic Plains（IGP） at Varanasi,which is a highly populated and polluted region due to its topography and extensive emission *** annual mean bC mass concentration was 8.92 ± 7.0 μg m-3,with 34%of samples exceeding the average ***,bC was highest during the post-monsoon and winter periods（approximately 18 μg m-3） and lower in the premonsoon/monsoon seasons（approximately 6 μg m-3）.The highest frequency（approximately 46%） observed for bC mass was in the interval from 5 to 10 μg ***,during the post-monsoon season,the most common values（approximately 23%） were between 20 and 25 μg *** nighttime concentrations of bC were approximately twice as much as the daytime values because of lower boundary layer heights at *** Angstrom exponent was significantly positively correlated（0.55） with ground-level bC concentrations,indicating the impact of bC on the columnar aerosol *** estimated mean absorption Angstrom exponent was 1.02 ± 0.08 μg m-3,indicating that the major source of bC was from fossil fuel *** negative correlations between bC mass and meteorological parameters indicate a pronounced effect of atmospheric dynamics on the bC mass in this *** highest mean bC mass concentration（18.1 ± 6.9 μg m-3） as a function of wind speed was under calm wind conditions（38%of the time）.

关键词： black carbon Indo-Gangetic Plains absorption Angstr(o|¨)m exponent biomass fossil fuel

Effects of rainwater harvesting on herbage diversity and productivity in degraded Aravalli hills in western India

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Journal of Forestry Research 2011年第3期22卷 329-340页

作者： G. Singh G.R. Choadhary b. Ram N.K. Limba Division of Forest Ecology Arid Forest Research Institute New Pali Road Jodhpur-342005 India

Over-exploitation and rural growth have severely damaged native vegetations of Aravalli hills in Rajasthan, India. This study was conducted to evaluate the effects of different restoration practices （i.e., rainwater harvesting （RWH） and planting of tree seedlings） on improve- ment in soil water and nutrients and growth and biomass of herbaceous vegetation. Contour trench （CT）, Gradonie （G）, box trench （bT）, V-ditch （VD） and a control were imposed on 75 plots （each of 700 m 2 ） in natural slope gradient defined as 10%, 10% 20% and 20% slopes in 2005. Each plot had three micro-sites of 1-m 2 at up （USP）, middle （MSP） and lower （LSP） part of the plot for observation in 2008. The existed gradient （due to soil texture and topographic features） of soil pH, EC, SOC, NH 4 - N, NO 3 -N and PO 4 -P in June 2005 between 20% to 10% slopes were decreased in 2008 after applying RWH techniques. Such improvement in soil status promoted vegetation growth and biomass in higher slope gra- dients. Soil water, species diversity and herbage biomass increased from USP to LSP, and RWH techniques had positive role in improving SOC, nutrients, vegetation population, evenness and growth at MSP. Despite of lowest SWC, regular rain and greater soil water usage enhanced green and dry herbage biomasses in 10% 20% and 20% slopes, compared with 10% slope. The highest diversity in CT treatment was related to herbage biomass, which was enhanced further by highest concentrations of SOC and PO 4 -P. Further, CT treatment was found to be the best treat- ment in minimizing biomass variance in different slopes. Conclusively, soil texture and topographic features controlled soil water and nutrients availability. Rainwater harvesting techniques increased soil water storage and nutrient retention and also enhanced vegetation status and biomass by minimizing the effects of hillslopes. Thus depending upon the site conditions, suitable RWH technique could be adopted to increase herb- age biomass while rehabilit

关键词： herbage growth and biomass hillslopes soil nutrients soil water dynamics vegetation diversity

III-Nitride-based Quantum Dots and Their Optoelectronic Applications

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Nano-Micro Letters 2011年第3期3卷 200-207页

作者： G.E.Weng A.K.Ling X.Q.Lv J.Y.Zhang b.P.Zhang Department of Physics Laboratory of Micro-Nano Optoelectronics Xiamen University MEMS Research Center Xiamen University

During the last two decades, III-nitride-based quantum dots(QDs) have attracted great attentions for optoelectronic applications due to their unique electronic properties. In this paper, we first present an overview on the techniques of fabrication for III-nitride-based QDs. Then various optoelectronic devices such as QD lasers, QD light-emitting diodes(LEDs), QD infrared photodetectors(QDIPs) and QD intermediate band(QDIb) solar cells(SCs) are discussed. Finally, we focus on the future research directions and how the challenges can be overcome.

关键词： III-nitride-based quantum dots Lasers Light-emitting diods Infrared photodetectors Solar cells

Oxidative leaching kinetics of molybdenum-uranium ore in H2SO4 using H2O2 as an oxidizing agent

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 95-102页

作者： T. A. Lasheen M. E. EI-ahmady H. b. Hassib A. S. Helal Nuclear Materials Authority Cairo Egypt Chemistry Department Faculty of Science Cairo University Giza Egypt

The processing of molybdenum-uranium ore in a sulfuric acid solution using hydrogen peroxide as an oxidant has been investigated. The leaching temperature, hydrogen peroxide concentration, sulfuric acid concentration, leaching time, particle size, liquid-to-solid ratio and agitation speed all have significant effects on the process. The optimum process operating parameters were： temperature： 95℃; H2O2 concentration： 0.5 M; sulfuric acid concentration： 2.5 M; time： 2 h; particle size： 74 gm, liquid-to-solid ratio： 14 ： 1 and agitation speed： 600 rpm. Under these experimental conditions, the extraction efficiency of molybdenum was about 98.4%, and the uranium extraction efficiency was about 98.7%. The leaching kinetics of molybdenum showed that the reaction rate of the leaching process is controlled by the chemical reaction at the particle surface. The leaching process follows the kinetic model 1 - （1-X）1/3 = kt with an apparent activation energy of 40.40 kJ/mole. The temperature, concentrations of H202 and H2SO4 and the mesh size are the main factors that influence the leaching rate. The reaction order in H2SO4 was 1.0012 and in H202 it was 1.2544.

关键词： leaching of molybdenum leaching of uranium kinetics

Comparison of Phosphorus Sorption by Light-Weight Aggregates Produced in the United States

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Pedosphere 2014年第6期24卷 808-816页

作者： M.D.bAKER S.SIMKINS L.A.SPOKAS P.L.M.VENEMAN b.S.XING Stockbridge School of Agriculture University of MassachusettsAmherstMA 01003 (USA) U.S.Army Fort HoodTX 76544 (USA)

In this study, phosphorus(P) sorption of thirteen light-weight aggregates(LWAs) from USA was compared during batch equilibrium experiments in order to identify those materials which had the highest P sorption capacity for further study. Seven different levels of sorption activity were observed, which were broadly grouped into three categories—high performing, middle performing, and low performing aggregates. Chemical analysis of Ca, Al, Fe, and Mg was used to describe the differences between LWAs. There was a significant correlation between cation(especially Al, Ca, Fe, and Mg) content and P sorbed. Langmuir isotherms were used to describe P sorption maximum and binding affinity for four of the top five performing LWAs, Universal, Stalite "D", Stalite "Mix", and *** fifth aggregate, Lehigh, exhibited more complex sorption, and was better described by the Freundlich isotherm. Universal had a mean P sorption at the highest concentration of 824 mg kg-1, well above its calculated sorption maximum(702 mg kg-1), and also had the highest binding affinity(1.1 L mg-1). This experiment suggests that the top performing LWA(Universal) may perform poorly in column and field studies due to observed precipitates, which could degrade constructed wetland performance. Other LWAs may exhibit superior field performance due to their high calculated sorption maxima. In general, these results highlight the importance of batch experiments as a first step in identifying materials suitable for column and field experiments.

关键词： binding affinity constructed wetlands equilibrium P concentration media P sorption capacity

Influence of the SNPs on the structural stability of CbS protein： Insight from molecular dynamics simulations

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Frontiers in biology 2014年第6期9卷 504-518页

作者： C. GEORGE PRIYA DOSS b. RAJITH R. MAGESH A. ASHISH KUMAR Medical biotechnology Division School of Biosciences and Technology VIT University Vellore-14 TamilNadu India Department of btotechnology Faculty of Biomedical Sciences Technology & Research Sri Ramachandra University Chennai-600116 TamilNadu India biomformatlcs Division School of Biosciences and Technology VIT University Vellore-14 TamilNadu lndia

Cystathionine β-synthase is an essential enzyme of the trans-suifuration pathway that condenses serine with homocysteine to form cystathionine. Missense mutations in CbS are the major cause of inherited homocystinuria, and the detailed effect of disease associated amino acid substitutions on the structure and stability of human CbS is yet unknown. Here, we apply a unique approach in combining in silico tools and molecular dynamics simulation to provide structural and functional insight into the effect of SNP on the stability and activity of mutant CbS. In addition, principal component analysis and free energy landscape were used to predict the collective motions, thermodynamic stabilities and essential subspace relevant to CbS function. The obtained results indicate that C109R, E176K and D376N mutations have the diverse effect on dynamic behavior of CbS protein. We found that highly conserved D376N mutation, which is present in the active pocket, affects the protein folding mechanism. Our strategy may provide a way in near future to understand and study effects of functional nsSNPs and their role in causing homocystinuria.

关键词： CbS in silico molecular dynamics simulation SNPs

EFFECT OF COPPER IMPLANTATION ON ANTIbACTERIAL ACTIVITY OF AUSTENITIC STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 870-875页

作者： J.Xiong b.F.Xu H.W.Ni P.Y.Xiong Z.G.Dan SchoolofMaterialandMetallurgy WuhanUniversityofScienceandTechnologyWuhan430081China SchoolofMedicineScience WuhanUniversityofScienceandTechnologyWuhan430081China

Antibacterial activity has been studied by copper ion implantation into 0Cr18Ni9 stainless steel. Ions extracted from a metal vapor vacuum arc (MEVVA) are sourced with 60-100keV energy and a dose range (0.2-2.0)×1017 ions cm-2. Saturation doses, surface concentration were calculated and the relationships between energy, dose and antibacterial activity were analyzed. Novel phases such as Fe4Cu3 and Cu0.81Ni0.19 were found after copper implantation by X-ray diffraction. The novel phases, effects on antibacterial activity have been investigated. The results show that saturation dose varies with the ions' energy. Antibacterial activity has close relation with copper,s concentration in implanted layer and Cu-rich phase.

关键词： stainless steel copper ion implantation saturation dose concentration in implanted layer antibacterial activity

The class A macrophage scavenger receptor type I (SR-AI) recognizes complement iC3b and mediates NF-κb activation

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Protein & Cell 2010年第2期1卷 174-187页

作者： Jason W.K.Goh Yen Seah Tan Alister W.Dodds Kenneth b.M.Reid Jinhua Lu Department of Microbiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore MRC Immunochemistry Unit Department of BiochemistryUniversity of OxfordSouth Parks RoadOxford OX13QUUnited Kingdom Immunology Programme National University of SingaporeSingapore 117597Singapore

The macrophage scavenger receptor SR-AI binds to host tissue debris to perform clearance and it binds to bacteria for *** addition,SR-AI modulates macrophage activation through cell ***,investigation of SR-AI signaling on macrophages is complicated due to its promiscuous ligand specificity that overlaps with other macrophage ***,we expressed SR-AI on HEK 293T cells to investigate its ligand binding and *** 293T cells,SR-AI could respond to *** DH5α,leading to NF-κb activation and IL-8 ***,this requires *** DH5αto be sensitized by fresh serum that is treated with heat-inactivation or complement C3 ***-C3 antibody inhibits the binding of SR-AI to serum-sensitized DH5αand blocks DH5αstimulation of SR-AI *** analysis showed that SR-AI can directly bind to purified iC3b but not C3 or *** mutagenesis,The SRCR domain of SR-AI was found to be essential in SR-AI binding to serum-sensitized DH5α.These results revealed a novel property of SR-AI as a complement receptor for iC3b-opsonized bacteria that can elicit cell signaling.

关键词： SR-AI complement iC3b signalling 293T cells macrophage