检索结果-南通市图书馆

Water Science and Engineering 2021年第1期14卷 72-79页

作者： Vladimir joel Alzamora Guzman Julie Anne Glasscock Energy Research Group Kadagaya Research Centre for Appropriate TechnologyJunin 12866Peru

Strong free-surface water vortices are found throughout industrial hydraulic systems used for water treatment,flow regulation,and energy *** models using the volumetric flow rate as a model input have generally been semi-empirical,and have tended to have some limitations in terms of the design of practical hydropower *** this study,an analytical model of a strong free-surface water vortex was *** model only requires the water head and geometric parameters as its inputs and calculates the maximum volumetric flow rate,aircore diameter,and rotational *** experimental depthedischarge data from a full-scale gravitational vortex hydropower system,unavailable in the relevant literature,were obtained,and the simulated results showed excellent agreement with the experimental *** data could be used to verify similar models using laboratory-scale physical models in order to investigate the scaling *** contrast to previous models,this model does not assume a constant average velocity across the vortex radius and allows precise calculation of the resultant velocity ***,this model presents advantages in turbine design for energy generation systems.

关键词： Gravitational vortex Velocity measurements Scalability Analytical model Microhydropower

Shade shelters increase survival and photosynthetic performance of oak transplants at abandoned fields in semi-arid climates

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2013年第1期24卷 23-28页

作者： Claudia González-Salvatierra Ernesto Iván Badano joel Flores Juan Pablo Rodas División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José 2055C.P. 78216San Luis PotosíS.L.P.México.

Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a Mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors： white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates.

关键词： chlorophyll fluorescence light stress photoinhibition reforestation forest restoration

Multi-frequency dielectrophoretic characterization of single cells

在线全文

学校读者我要写书评

暂无评论

Microsystems & nanoengineering 2018年第1期4卷 156-164页

作者： Alex Jaffe joel Voldman Department of Electrical Engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMAUSA

We explore the use of dielectrophoresis to discern the electrical properties of single cells by observing them at multiple *** first simulate experimental conditions to show that as we increase the number of measured frequencies,we are able to better discriminate among different ***,we use the simulation to find the optimal number and value of frequencies to use to best discriminate among different cells in *** then fabricate a microfluidic device,calibrate it with polystyrene beads,and characterize it with BA/F3 *** this device,we test three different activation levels of HL60 cells treated with cytochalasin D using the optimal frequency sequence obtained in simulation to determine the differences in discrimination abilities depending on the number of frequencies *** quantify the discrimination abilities of the optimal one,two,and three frequencies by minimizing 0-1 loss.

关键词： optimal beads characterization

Towards a comprehensive understanding of p75 neurotrophin receptor functions and interactions in the brain

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

neural Regeneration Research 2022年第4期17卷 701-704页

作者： joel F.Ritala Seán BLyne Antti Sajanti Romuald Girard Janne Koskimäki Division of Clinical neurosciences Department of NeurosurgeryTurku University Hospital and University of TurkuTurkuFinland neurovascular Surgery Program Section of NeurosurgeryThe University of Chicago Medicine and Biological SciencesChicagoILUSA Department of Psychiatry Central Hospital of Southern OstrobothniaSeinäjokiFinland neuroscience Center HiLIFEUniversity of HelsinkiHelsinkiFinland

The role of neurotrophins in neuronal plasticity has recently become a strong focus in neuroregeneration research field to elucidate the biological mechanisms by which these molecules modulate synapses,modify the response to injury,and alter the adaptation ***,the prior studies highlight the role of p75 neurotrophin receptor(p75^(nTR))in various injuries and diseases such as central nervous system injuries,Alzheimer's disease and amyotrophic lateral *** comprehensive elucidation of the mechanisms,and therapies targeting these molecular signaling networks may allow for neuronal tissue regeneration following an *** to a diverse role of the p75^(nTR)in biology,the body of evidence comprising its biological role is diffusely spread out over numerous *** review condenses the main evidence of p75^(nTR)for clinical applications and presents new findings from published literature how data mining approach combined with bioinformatic analyses can be utilized to gain new hypotheses in a molecular and network level.

关键词： bioinformatics brain injury data mining neuron neurotrophins p75^(nTR) plasticity regeneration

Antiretroviral therapy related adverse effects:Can sub-Saharan Africa cope with the new“test and treat”policy of the World Health Organization?

在线全文

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2017年第1期6卷 212-216页

作者： Jobert Richie n.nansseu Jean joel R.Bigna Department of Public Health Faculty of Medicine and Biomedical Sciences of the University of YaoundeIPO Box 1364YaoundeCameroon Sickle Cell Disease Unit Mother and Child Centre of the Chantal Biya FoundationYaoundeCameroon Department of Epidemiology and Public Health Centre Pasteur of CameroonYaoundeCameroon Faculty of Medicine University of Paris Sud XILe Kremlin BicêtreParisFrance

Background:Recent studies have shown that early antiretroviral therapy(ART)initiation results in significant HIV transmission *** is the rationale behind the“test and treat”policy of the World Health Organization(WHO).Implementation of this policy will lead to an increased incidence of ART-related adverse effects,especially in sub-Saharan Africa(SSA).Is the region yet ready to cope with such a challenging issue?Main body:The introduction and widespread use of ART have drastically changed the natural history of HIV/AIDS,but exposure to ART leads to serious medication-related adverse effects mainly explained by mitochondrial toxicities,and the situation will get worse in the near ***,ART is associated with an increased risk of developing cardiovascular disease,lipodystrophy,prediabetes and overt diabetes,insulin resistance and hyperlactatemia/lactic *** prevalence of these disorders is already high in SSA,and the situation will be exacerbated by the implementation of the new WHO *** SSA countries are characterized by(extreme)poverty,very weak health systems,inadequate and low quality of health services,inaccessibility to existing health facilities,lack of(qualified)health personnel,lack of adequate equipment,inaccessibility and unaffordability of medicines,and heavy workload in a context of a double burden of ***,there is dearth of data on the incidence and predictive factors of ART-related adverse effects in SSA,to anticipate on strategies that should be put in place to prevent the occurrence of these conditions or properly estimate the upcoming burden and prepare an adequate response *** are required if we are to anticipate and effectively prevent this upcoming ***:While SSA would be the first region to experience the huge benefits of implementing the“test and treat”policy of the WHO,the region is not yet prepared to manage the consequential increased burden of ART-related toxic and

关键词： HIV/AIDS Test and treat 90-90-90 Antiretroviral therapy Sub-Saharan Africa

Phase transitions in four-dimensional AdS black holes with a nonlinear electrodynamics source

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2021年第12期73卷 119-128页

作者： Ramon Becar P A Gonzalez joel Saavedra Yerko Vasquez Bin Wang Departamento de Ciencias Matematicas y Fisicas Universidad Catolica de TemucoMontt 56Casilla 15-DTemucoChile Facultad de Ingenieria y Ciencias Universidad Diego PortalesAvenida Ejercito Libertador 441Casilla 298-VSantiagoChile Instituto de Ffsica Pontificia Universidad Catolica de ValparaisoCasilla 4950ValparaisoChile Departamento de Ffsica Facultad de CienciasUniversidad de La SerenaAvenida Cistemas 1200La SerenaChile Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

In this work we consider black hole solutions to Einstein’s theory coupled to a nonlinear powerlaw electromagnetic field with a fixed exponent *** study the extended phase space thermodynamics in canonical and grand canonical ensembles,where the varying cosmological constant plays the role of an effective thermodynamic *** examine thermodynamical phase transitions in such black holes and find that both first-and second-order phase transitions can occur in the canonical ensemble while,for the grand canonical ensemble,Hawking-Page and second-order phase transitions are allowed.

关键词： black hole thermodynamics nonlinear Maxwell

Relativistic charged stellar modeling with a perfect fluid sphere

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2023年第9期75卷 113-121页

作者： Joaquin Estevez-Delgado joel Arturo Rodríguez Ceballos Jorge Mauricio Paulin-Fuentes JoséVega Cabrera Antonio Rendón Romero Facultad de Ciencias Físico Matemáticas de la Universidad Michoacana de San nicolás de Hidalgo Edificio BCiudad UniversitariaMorelia MichoacánCP 58040Mexico Facultad de Químico Farmacobiología de la Universidad Michoacana de San nicolás de Hidalgo Tzintzuntzan No.173Col.MatamorosMorelia MichoacánC.P.58240Mexico División Académica de Ciencias Básicas de la Universidad Juárez Autónoma de Tabasco Carretera Cunduacán-Jalpa Km.1Col.La Esmeralda86690CunduacánTabascoMexico Facultad de Ingenieria Mecanica de la Universidad Michoacana de San nicolás de Hidalgo Edificio W Ciudad UniversitariaCP 58030Morelia MichoacánMexico

In this report we present the generalization of a solution to Einstein's equations with perfect fluid for the case of Einstein–Maxwell with perfect *** effect of the charge is reflected by a parameter,ν,and its interval is determined by the positivity condition from the pressure in the interior of the *** is shown that the solution is stable according to the Zeldovich criteria as well as in relation to the criteria of the adiabatic *** compactness,u=GM/c^(2)R,of this charged model is greater than it is for the chargeless case as a result of the effect of the presence of the *** allows it to represent stars with a high compactness,in particular a graphic analysis is presented for the star SAX J1808.4-3658 with mass M=1.435M_(⊙)and radius R=7.07 *** these data and employing the solution,we obtain that the total maximum charge for the star is Q=2.4085×10^(20)C.

关键词： general relativity exact solutions charged fluid stars models

Influence of the Iron Anisothermal Sintering on the Characteristic of the Hollow Cathode Discharge

在线全文

学校读者我要写书评

暂无评论

材料热处理学报 2004年第5期25卷 83-87页

作者： BRUnATTO Silvio Francisco MUZART joel Louis Rene Department of Mechanical Engineering UFPR 81531-990 Curitiba-PR BrazilDepartment of Mechanical Engineering UFSC 88040-900 Florianopolis-SC Brazil

This work studies the influence of anisothermal iron sintering process on hollow cathode discharge characteristics. Two independent cathodes form an annular discharge. The pressed cylindrical iron powder sample, acting as central cathode, was placed concentrically in the interior of an external cathode. The external cathode, machined from an AISI 310 steel bar, besides acting to confine the geometry of the plasma, can also acts as a source of alloying elements. The sample heating is a function of the ion bombardment energy and, so, of the discharge electrical parameters: current (or current density) and the effective potential applied to the cathode. Successive anisothermal sintering is performed in a same sample until the reproducibility of the electrical parameters being obtained. The heating experiments up to 1250 °C, in a gas mixture of 80% Ar + 20% H2, at pressure of 133 Pa, at flow of 2xlO"6 mV, with an inter-cathode radial space of 5.8 mm, were carried out. It was verified the metallurgical evolution of the iron sample sintering process influences the current-?0n (time switched-on of the pulse) characteristics of the discharge.

关键词：空心阴极放电等离子体焊结烧结铁溅射非等温焙烧

Factors associated with non-adherence to scheduled medical follow-up appointments among Cameroonian children requiring HIV care: a case-control analysis of the usual-care group in the MORE CARE trial

在线全文

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2014年第1期3卷 415-422,414页

作者： Jean joel R Bigna Jean Jacques n noubiap Claudia S Plottel Charles Kouanfack Sinata Koulla-Shiro Faculty of Medicine and Biomedical Sciences University of Yaoundé1P.O.Box 1364YaoundéCameroon Faculty of Medicine University of Montpellier 1MontpellierFrance Preventing Mother to Child Transmission Unit Goulfey District HospitalGoulfeyCameroon Internal Medicine Unit Edéa Regional HospitalEdéaCameroon Department of Medicine New York University Langone Medical CenterNew YorkUSA Accredited Treatment Centre Yaoundé Central HospitalYaoundéCameroon Infectious Diseases Unit Yaoundé Central HospitalYaoundéCameroon

Background:A better understanding of why HIV-exposed/infected children fail to attend their scheduled follow-up medical appointments for HIV-related care would allow for interventions to enhance the delivery of *** aim of this study was to determine characteristics of the caregiver-child dyad(CCD)associated with children’s non-adherence to scheduled follow-up medical appointments in HIV programs in ***:We conducted a case-control analysis of the usual-care group of CCDs from the MORE CARE trial,in which the effect of mobile phone reminders for HIV-exposed/infected children in attending follow-up appointments was assessed from January to March *** this study,the absence of a child at their appointment was considered a case and the presence of a child at their appointment was defined as a *** used three multivariate binary logistic regression *** best-fit model was the one which had the smallest chi-square value with the Hosmer-Lemeshow test(HLχ^(2)).Magnitudes of associations were expressed by odds ratio(OR),with a p-valuensidered as statistically ***:We included 30 cases and 31 *** best-fit model which considered the sex of the adults and children separately(HLχ^(2)=3.5)showed that missing scheduled medical appointments was associated with:lack of formal education of the caregiver(OR 29.1,95%CI 1.1-777.0;p=0.044),prolonged time to the next appointment/follow-up(OR[1 week increase]1.4,95%CI 1.03-2.0;p=0.032),and being a female child(OR 5.2,95%CI 1.2-23.1;p=0.032).One model(HLχ^(2)=10.5)revealed that woman-boy pairs adhered less to medical appointments compared to woman-girl pairs(OR 4.9,95%CI 1.05-22.9;p=0.044).Another model(HLχ^(2)=11.1)revealed that man-boy pairs were more likely to attend appointments compared to woman-girl pairs(OR 0.23,95%CI 0.06-0.93;p=0.039).There were no statistical associations for the ages of the children or the caregivers,the study sites,or the HIV status(confirmed vs.

关键词： MORE CARE Lost to follow-up(LTFU) Appointment Adherence Children Cameroon HIV AIDS Preventing mother-to-child transmission(PMTCT) Missed scheduled medical appointment

Dimensional heterojunction design:The rising star of 2D bismuthbased nanostructured photocatalysts for solar-to-chemical conversion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

nano Research 2023年第4期16卷 4310-4364页

作者： joel Jie Foo Sue-Faye ng Wee-Jun Ong School of Energy and Chemical Engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Center of Excellence for nano Energy&Catalysis Technology(COnnECT) Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China Shenzhen Research Institute of Xiamen University Shenzhen 518057China

With the fast-pace digitalization evolution in the current generation’s lifestyle and the industry revolution,the energy demand has been ***,the two-dimensional(2D)bismuth-based nanomaterials emerged as a promising photocatalyst candidate in solar fuel conversion,not only for its exceptional light absorption capability and tunable optical properties,but it also can be synthesized into diverse variety of nanomaterials with different ranges of potential gap and band position to fulfill the potential requirement of wide range of photocatalytic ***,the weak light harvesting ability and ultrafast charge recombination has restricted its potential in commercial ***,recent researches have been focusing on tackling these issues by incorporating some modification strategies such as heteroatom doping,vacancy engineering,facet engineering,bismuth rich strategy and heterojunction ***,this review article presents the state-of-the-art modifications on 2D bismuth-based parent material,specifically on the relationship between each of the modification strategy on the electronic properties and surface chemistry in achieving boosted photocatalytic *** the view of the unique charge interaction between two semiconductors with different dimensions,we systematically discuss the rational heterostructure design from the dimensionality perspective,namely,point-to-face,line-to-face,face-to-face,and bulk-to-face in solar fuel conversion to provide inspiring insights for future interface ***,the challenges and the future research outlook in the solar-to-fuel conversion are highlighted to push forward the design of high-performance bismuth-based photocatalyst in realizing commercialscale solar-to-fuel conversion.

关键词： 2D heterojunction 2D nanomaterial CO_(2)reduction water splitting n2 fixation Z-scheme