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Blockage and distortion effects on a vane-island type diffuser performance of centrifugal pumps for various flow rates

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排灌机械工程学报 2016年第12期34卷 1013-1021页

作者： SI Qiaorui DAZIN Antoine DUPONT patrick ROUSSETTE Olivier BOIS Gérard National Research Center of Pumps Jiangsu University Laboratoire de mécanique de Lille (UmR CNRS 8107) Arts et Métiers ParisTech Laboratoire de mécanique de Lille(UmR CNRS 8107) Ecole Centrale de Lille

Experimental investigation of mean flow velocity and pressure inside the vane-island type diffuser passage of a test centrifugal pump model is presented.A directional three-hole probe was used to investigate hub-to-shroud flow properties at diffuser leading and trailing edge *** addition,the mid-section between suction and pressure sides along the diffuser passage was also *** these measurements were performed at five different flow *** flow structures at the inlet section of the diffuser and along with the passage were analyzed in detail,with a focus on the flow distribution and the pressure recovery evolution of different diffuser *** and distortion effects were analyzed by using existing published particle image velocimetry(PIV)measurements in the outer part of the impeller and around the diffuser throat in order to get a better understanding of the overall performances and local flow structures of such a diffuser *** results show that back flows occur on the shroud region from impeller exit plane up to the semi-vaneless part of the diffuser at low flow *** blockage effects combining with blade thickness geometrical blockage tend to diminish the effects of theoretical high positive *** high flow rates,negative incidence effects induce high local velocity on the pressure side of the diffuser just after the *** aerodynamic blockage associated with low flow distortions are found to have a beneficial effect on pressure recovery for low flow *** the contrary,high flow distortions are found for increased flow rates,resulting in a low pressure recovery inside the semi-vane less part of the diffuser and after the throat.

关键词： vane island diffuser flow structure pressure recovery three-hole probe particle image velocimetry

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metal Fabrication by Additive manufacturing Using Laser and Electron Beam melting Technologies

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Journal of materials Science & Technology 2012年第1期28卷 1-14页

作者： Lawrence E. murr Sara m. Gaytan Diana A. Ramirez Edwin martinez Jennifer Hernandez Krista N. Amato patrick W. Shindo Francisco R. medina Ryan B. Wicker Department of metallurgical and materials Engineering The University of Texas at El PasoEl Paso TX 79968 USA W.m. Keck Center for 3D Innovation The University of Texas at El PasoEl Paso TX 79968 USA

Lawrence E. murr is mr.J mrs. macintosh murehison Professor and Chairman of the Department of metallurgical and materials Engineering and Ph.D. Program Director in the materials Research Technology Institute at The University of Texas at El Paso. Dr. murr received his ***. in physical science from Albright College, and his B.S.E.E. in electronics, his m.S. in engineering mechanics, and his Ph.D. in solidstate science, all from the Pennsylvania State University. Dr. murr has published 20 books, over 750 scientific and technical articles in a wide range of research areas in materials science and engineering, environmental science and engineering, manufacturing science and engineering （especially rapid prototype/layered manufacturing）,

关键词： Selective laser melting Electron beam melting Additive manufacturing microstructures microstructural architecture

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

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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 transmission 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

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Assessing Chemical mixtures and Human Health: Use of Bayesian Belief Net Analysis

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Journal of Environmental Protection 2012年第6期3卷 462-468页

作者： Anindya Roy neil J. Perkins Germaine m. Buck Louis Department of mathematics and Statistics University of Maryland Baltimore County Baltimore USA Division of Epidemiology Statistics & Prevention Research Eunice Kennedy Shriver National Institute of Child Health & Human Development Rockville USA

Background: Despite humans being exposed to complex chemical mixtures, much of the available research continues to focus on a single compound or metabolite or a select subgroup of compounds inconsistent with the nature of human exposure. Uncertainty regarding how best to model chemical mixtures coupled with few analytic approaches remains a formidable challenge and served as the impetus for the study. Objectives: To identify the polychlorinated biphenyl (PCB) congener(s) within a chemical mixture that was most associated with an endometriosis diagnosis using novel graphical modeling techniques. methods: Bayesian Belief Network (BBN) models were developed and empirically assessed in a cohort comprising 84 women aged 18 - 40 years who underwent a laparoscopy or laparotomy between 1999 and 2000;79 (94%) women had serum concentrations for 68 PCB congeners quantified. Adjusted odds ratios (AOR) for endometriosis were estimated for individual PCB congeners using BBN models. Results: PCB congeners #114 (AOR = 3.01;95% CI = 2.25, 3.77) and #136 (AOR = 1.79;95% CI = 1.03, 2.55) were associated with an endometriosis diagnosis. Combinations of mixtures inclusive of PCB #114 were all associated with higher odds of endometriosis, underscoring its potential relation with endometriosis. Conclusions: BBN models identified PCB congener 114 as the most influential congener for the odds of an endometriosis diagnosis in the context of a 68 congener chemical mixture. BBN models offer investigators the opportunity to assess which compounds within a mixture may drive a human health effect.

关键词： Bayesian Belief Network Endometriosis Environment mixtures Polychlorinated Biphenyls

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Parallel personal measurements of diesel engine exhaust and crystalline silica using dual sampling port

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International Journal of mining Science and Technology 2020年第3期30卷 313-319页

作者： Alan Fleck Caroline Couture Virginie Cabelguen patrick Eddy Ryan Ross Thuot Guillaume Lachapelle Hugo Coulombe maximilien Debia Department of Environmental and Occupational Health University of MontrealMontreal H3T 1A8Canada Health and Safety Agnico Eagle MinesToronto M5C 2Y7Canada Health and Safety Westwood Mine(IAMGOLD)Preissac J0Y 2E0Canada

Diesel engine exhaust(DEE) and crystalline silica exposures occur simultaneously in the mining industry,and occupational sampling campaigns can be time-and cost-consuming. The authors evaluated a dualport system for simultaneous sampling of DEE and crystalline silica in laboratory and field *** tests evaluated the operation of pumps during 8 h sampling and the intensity of the flow variation for various filter loading conditions and for different modes of operation. Field validation was performed in an underground mine. Pumps operated in constant flow or constant pressure *** in constant flow mode showed that when the flowrate increased on one side of the system, it decreased on the opposite side according to the loading intensity. Tests in constant pressure mode showed that flowrates systematically decreased when using loaded cassettes. However, the higher the backpressure setting, the lower the flow variation was. Flow variations during field tests were generally within the acceptable ±5% range. However, significant flow variations were identified in higher concentrations. A significant negative correlation was found between flowrate variation and total carbon concentration. While the majority of tests support the use of the dual-port for evaluating concomitant exposures, results highlight the possibility of filter overloading as a cause of flowrate changes.

关键词： Crystalline silica Diesel engine exhaust Dual-port mining monitoring

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Determination of Level of Knowledge on modern methods of Family Planning among Women of Reproductive Age (18 - 49 Years) at mathare North Health Center in Nairobi County, Kenya

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Open Journal of Nursing 2021年第5期11卷 407-421页

作者： patrick marangu m’rinkanya Catherine mutunga-mwenda Jane Karonjo mount Kenya University Thika Kenya

Introduction: modern family planning methods (mFPm) prevent unwanted pregnancies, reduce fertility rate, and increase the interval between pregnancies. They prevent pregnancy by preventing fertilization or implantation of the fertilized ovum. mFPm include tubal ligation (TL), vasectomy, oral contraceptive pills, the intrauterine contraceptive device (IUCD), depot injections, sub-dermal implants, and male and female condoms. Objective: To determine the level of knowledge of modern family planning methods (mFPm) among women of reproductive age (18 - 49 years) at the mathari North Health Center in Nairobi County, Kenya. methods: The study conducted among women of reproductive age at mathare North Health Center in Nairobi was a cross-sectional descriptive survey between march 2016 and November 2018. It provided both qualitative and quantitative data. The sample size comprised of 274 women of reproductive age,m> i.e.m> (18 - 49 years) attending antenatal and postnatal clinics at the facility. Those excluded were women below 18 years of age, as they could not give consent according to Kenyan Laws. The data were collected using an interviewer-administered structured questionnaire, which consisted of socio-demographic and characteristics, knowledge of modern family planning methods and distance from the facility. Likert scale was used to ensure that data was tabulated on daily basis and subjected to statistical manipulation using Statistical Package for Social Sciences (SPSS). Results: The four leading mFPm in use in order of acceptability were injectables, implants, intrauterine contraceptive device and pills in that order. 91% of respondents were aware or had heard about modern family planning methods. Level of education of mother and father were the two variables that influenced the uptake of mFPm with m>pm>-values of 0.0260 and 0.025, respectively. The study further found that knowledge of mFP

关键词： Antenatal Care Postnatal Care Contraceptives Family Planning Fertility modern Family Planning methods i.e. Injectables Implants Pills Intrauterine Cervical Device

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Advances in treatment and prevention of hepatitis B

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2021年第4期12卷 56-78页

作者： Niraj James Shah mark m Aloysius neil Rohit Sharma Kumar Pallav Department of Internal medicine Digestive DiseaseUniversity of Mississippi Medical CenterJacksonMS 39216United States Department of Internal medicine The Wright Center for Graduate Medical EducationScrantonPA 18505United States Department of Internal medicine Interventional Oncology and Surgical EndoscopyParkview Regional Medical CenterParkview Cancer InstituteFort WayneIN 46845United States

Chronic hepatitis B(CHB)continues to contribute to worldwide morbidity and mortality ***,clinicians,pharmaceutical companies,and health organizations have dedicated substantial Intellectual and monetary resources to finding a cure,increasing immunization rates,and reducing the global burden of *** and international health-related organizations including the center for disease control,the national institute of health,the American Association for the study of liver disease(AASLD),The European association for the study of the Liver(EASL),The Asia Pacific association for the study of the Liver(APASL)and the world health organization release periodic recommendations for disease prevention and *** review of the most recent guidelines by EASL,AASLD,APASL,and Taiwan Association for the Study of the Liver revealed that an overwhelming majority of cited studies were published before *** reviewed Hepatitis B-related literature published 2018 onwards to identify recent developments and current barriers that will likely direct future efforts towards eradicating hepatitis *** breakthrough in our understanding of the hepatitis B virus life cycle and resulting drug development is encouraging with significant room for further *** from high-risk populations,most vulnerable to the devastating effects of hepatitis B infection and reactivation remain *** of systems approach,optimization of experimental models,identification and validation of next-generation biomarkers,and precise modulation of the human immune response will be critical for future *** the foreseeable future,new treatments will likely complement conventional therapies rather than replace *** Importantly,pragmatic management of CHB related population health challenges must be prioritized to produce real-world results.

关键词： Chronic hepatitis B Hepatitis B virus Hepatitis B prevention Hepatitis B treatment Hepatitis B vaccination Hepatitis B reactivation

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The Role and Effectiveness of Local Institutions in the management of Forest Biodiversity in New Dabaga-Ulongambi Forest Reserve,Iringa Region-Tanzania

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Chinese Journal of Population,Resources and Environment 2012年第1期10卷 111-115页

作者： Richard A.Giliba Zacharia J.Lupala Canisius J.Kayombo Yobu m.Kiungo patrick mwendwa Forestry Training Institute Tanzania Kilolo District Natural Resources Office Iringa Jomo Kenyatta University of Agriculture and Technology Kenya

This paper examines the role and effectiveness of locacal institutions in the management of forest biodiversity in New Dabaga-Ulongambi Forest Reserve, Tanzania. Data were obtained through questionnaires, interviews, focus group discussions, participatory rural appraisal and field observations. The study revealed that the most remarkable local institutions connected to forest biodiversity management include： Village Natural Resources man- agement Committee （92%）, tree nursery group （79.4%）, beekeep- ing groups （61.1%）, fish fanning （43.3%）, livestock rearing group （33.9%）. main activities carried out by local institutions which directly contribute to the sustainability Of forest reserve include： forest patrols, fire extinguish, preparation of fire breaks, plant- ing of trees along the forest boundaries, creation of awareness, arresting of forest defaulters, participation in income generation activities. For the purpose of realization that local communities are capable of managing forest biodiversity through their traditional institutions, the policy should provide tangible opportunity for local communities to meet their needs as they manage the forests.

关键词： local institution participatory forest management forest biodiversity

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Tetraphenylethylene-BODIPY aggregation-induced emission luminogens for near-infrared polymer light-emitting diodes

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Science China Chemistry 2018年第8期61卷 932-939页

作者： Sebnem Baysec Alessandro minotto patrick Klein Simone Poddi Andrea Zampetti Sybille Allard Franco Cacialli Ullrich Scherf macromolecular Chemistry and Institute for Polymer Technology Bergische Universitat Wuppertal Wuppertal 42097 Germany Department of Physics and Astronomy and London Centre for Nanotechnology University College London London WCIE 6BT UK

The aggregation-induced emission(AIE) phenomenon provides a new direction for the development of organic light-emitting devices. Here, we present a new class of emitters based on 4,4-difluoro-4-bora-3 a,4 a-diaza-s-indacene(BODIPY), functionalized at different positions with tetraphenylethylene(TPE), which is one of the most famous AIE luminogens. Thanks to this modification, we were able to tune the photoluminescence of the BODIPY moiety from the green to the near-infrared(NIR)spectral range and achieve PL efficiencies of ~50% in the solid state. Remarkably, we observed an enhancement of the AIE and up to ~100% photoluminescence efficiencies by blending the TPE-substituted BODIPY fluorophores with a poly[(9,9-di-noctylfluorene-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,7-diyl)](F8 BT) matrix. By incorporating these blends in organic lightemitting diodes(OLEDs), we obtained electroluminescence peaked in the range 650–700 nm with up to 1.8% external quantum efficiency and ~2 m W/cm2 radiance, a remarkable result for red/NIR emitting and solution-processed OLEDs.

关键词： BODIPY organic light-emitting diode aggregation-induced emission NIR emission photoluminescence electro luminescence

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Differential mRNA Translation in medicago truncatula Accessions with Contrasting Responses to Ozone-Induced Oxidative Stress

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molecular Plant 2012年第1期5卷 187-204页

作者： michael Puckett Niranjani J. lyer YuhongTang Xin-Bin Dai patrick Zhao Ramamurthy mahalingam 246 Noble Research Center Department of Biochemistry and Molecular Biology Oklahoma State University Stillwater OK 74078 USA Samuel Roberts Noble Foundation 2510 Sam Noble Parkway Ardmore OK 73401 USA

Acute ozone is a model abiotic elicitor of oxidative stress and a useful tool for understanding biochemical and molecular events during oxidative signaling. Two medicago truncatula accessions with contrasting responses to ozone were used to examine translational regulation during ozone stress. In ozone-resistant JE154, significant reduction in ri- bosome loading was observed within one hour of ozone treatment, suggesting energy homeostasis as a vital factor for oxidative stress management. Polysomal RNA-based expression profiling with Affymetrix arrays revealed extensive changes in the translatomes of both accessions. messenger RNAs with low GC content in their 5＇ and 3＇-UTRs were pref- erentially associated with polysomes during oxidative stress. Genebins analysis revealed extensive changes in various gene ontologies in both accessions. Extensive changes in nicotinate and nicotinamide metabolism genes were corrobo- rated with increased levels of NAD＋ and NADH in JE154. The significantly lower NAD＋：NADH redox status in JE154, in conjunction with higher ATP amounts, provided a cellular milieu conducive for overcoming oxidative stress. Low levels of ATP, NADH, and suppression of antioxidant defense responses, abet build-up of ozone-derived ROS and ultimately lead to oxidative cell death in Jemalong.

关键词： Abiotic/environmental stress oxidative and photo-oxidative stress gene expression medicago truncatula.

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