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Friction 2024年第8期12卷 1882-1896页

作者： Julio A.CAO-rOMErO-GALLEGOs saeid TAGHIZADEH Oscar A.AGUILAr-rOsAs r.s.dwyer-joyce Leonardo I.FArFAN-CABrErA Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501MonterreyN.L.64849México Department of Mechanical Engineering Leonardo Centre for TribologyUniversity of SheffieldSheffield S13JDUK

This work explores experimentally the effects of DC electrical currents on lubricant film thickness alteration in lubricated sliding steel contacts in the boundary and mixed regime as measured by *** experiments were performed in a two-electrode cell-based pin-on-disk tester instrumented with ultrasonic *** and electrified tribological tests were conducted on steel flat-on-flat contacts under various speeds and loads using both a mineral base oil and a gear *** thickness,coefficient of friction(CoF),and electrical contact resistance(ECr)were measured during short experiments(30 s)in unelectrified and electrified(1.5 and 3 A)*** results suggest that film thickness,CoF,and all ECr are altered by passing DC currents through the *** particular,film thickness increased and decreased,respectively,by applying electricity at the different speeds and loads *** alterations were majorly ascribed to oil viscosity decrease by local heat and surface oxidation caused by electrical discharge and break down at the interface.

关键词： electrified sliding ultrasonic measurement electric vehicles pin-on-disk

Experimental procedure for mapping Hertzian contacts

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science China Mathematics 2001年第S1期44卷 423-430页

作者： r. s. dwyer-joyce A.M.Quinn B.W.Drinkwater Department of Mechanical Engineering Mappin Street University of SheffieldSheffield S1 3JD UK Department

When ultrasound is incident at the interface between two rough surfaces some of thewave is reflected. The proportion of the wave reflected is related to the level of conformity betweenthe two surfaces. This principle is under investigation as a method to determine the area of contactand the load distribution, between contact elements in machine components. In this work theHertzian contact between a ball and a flat surface has been scanned ultrasonically. The resultingreflection maps have been related to the local nominal contact pressure within the contact by acalibration procedure. The resolution of the measurement system is of the same order as the con-tact dimensions. To interpret the results both convolution and deconvolution numerical procedureshave been used. The resulting measured contact pressures agree well with theoretical predictedHertz pressure.

关键词： contact area ultrasound rough surface contact real area of contact measurement

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Quasi-isothermal modulated DsC as a valuable characterisation method for soft tissue biomaterial crosslinking reactions

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Bioactive Materials 2020年第2期5卷 428-434页

作者： K.joyce s.rahmani Y.rochev Centre for research in Medical Devices(CÚrAM) Biomedical SciencesNational University of Ireland Galway(NUIG)Newcastle RoadGalwayIreland Boston scientific Limited Ballybrit Business ParkGalwayIreland National University of Ireland GalwayUniversity RoadGalwayIreland Institute for regenerative Medicine Sechenov University8-2 Trubetskaya St.Moscow119991Russia

Glutaraldehyde(Glut)is an extensively used sterilant and fixative for the crosslinking of natural soft tissue biomaterials like bovine pericardium(BP)to provide stability and is required for its application in *** is plenty of debate around the reaction mechanism of Glut with natural *** scanning calorimetry(DsC)is a commonly used technique that is typically used to measure the thermal profile of ***,a variation known as quasi-isothermal modulated differential scanning calorimetry(QiMDsC)has been utilised for the analysis of polymorphic transformations in both the pharmaceutical and food *** communication will address QiMDsC as a method for analysing soft tissue biomaterials and their crosslinking mechanisms and how it can be applied to other biomaterial applications.

关键词： Glutaraldehyde QiMDsC Bovine pericardium

Center for Plant Conservation's Best Practice Guidelines for the reintroduction of rare plants

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Plant Diversity 2017年第6期39卷 390-395页

作者： joyce Maschinski Matthew A.Albrecht Center for Plant Conservation San Diego Zoo Global Center for Conservation & sustainable Development Missouri Botanical Garden

recent estimates indicate that one-fifth of botanical species worldwide are considered at risk of becoming extinct in the wild. One available strategy for conserving many rare plant species is reintroduction, which holds much promise especially when carefully planned by following guidelines and when monitored long-term. We review the Center for Plant Conservation Best reintroduction Practice Guidelines and highlight important components for planning plant reintroductions. Before attempting reintroductions practitioners should justify them, should consider alternative conservation strategies, understand threats, and ensure that these threats are absent from any recipient site. Planning a reintroduction requires considering legal and logistic parameters as well as target species and recipient site *** selecting the genetic composition of founders, founder population size, and recipient site will influence establishment and population growth. Whenever possible practitioners should conduct reintroductions as experiments and publish results. To document whether populations are sustainable will require long-term monitoring for decades, therefore planning an appropriate monitoring technique for the taxon must consider current and future needs. Botanical gardens can play a leading role in developing the science and practice of plant reintroduction.

关键词： reintroduction Monitoring Genetics Optimal site selection Founders Managed relocation

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T cells from induced and spontaneous models of sLE recognize a common T cell epitope on β2-glycoprotein Ⅰ

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Cellular & Molecular Immunology 2019年第8期16卷 685-693页

作者： David salem rebecca subang Masataka Kuwana Jerrold s.Levine joyce rauch Division of rheumatology Department of MedicineResearch Institute of the McGill University Health CentreMontrealQCCanada Department of Allergy and rheumatology Nippon Medical SchoolGraduate School of MedicineTokyoJapan section of Nephrology Department of MedicineUniversity of Illinois at ChicagoChicagoILUSA section of Nephrology Department of MedicineJesse Brown Veterans Affairs Medical CenterChicago IL USA

systemic lupus erythematosus is a prototypic model for B-cell epitope spread in *** to numerous molecularly distinct self-antigens emerge in a sequential manner over several years,leading to disease *** the earliest autoantibodies to appear are those targeting phospholipid-binding proteins,particularlyβ2-glycoprotein Ⅰ.Notably,mice immunized with β2-glycoprotein Ⅰ and lipopolysaccharide develop a strong T cell response to β2-glycoprotein Ⅰ that is associated with autoantibody production and renal disease,similar to that seen in human *** we hypothesized that mice with murine systemic lupus erythematosus,whether induced or spontaneous,should have T cells that recognizeβ2-glycoprotein *** evaluated the response of splenic T cells from mice with induced(C57BL/6 and C3H/HeN)and spontaneous(MrL/lpr)systemic lupus erythematosus to peptides spanning the entire sequence of humanβ*** found that mice with induced and spontaneous systemic lupus erythematosus recognize a common T cell epitope(peptide 31;LYrDTAVFECLPQHAMFG)in domain Ⅲ ofβ2-glycoprotein I.β2GPI-reactive CD4^(+)T cells from the two models differed primarily in cytokine production:T cells from mice with induced sLE expressed IFN-γ,while T cells from MrL/lpr mice expressed both IL-17 and IFN-γ,indicating that IL-17-expressing T cells are not necessary for generating aβ2GPI-reactive T cell *** data suggest that the generation of aβ2-glycoprotein Ireactive T cell response is shared by both induced and spontaneous models of systemic lupus erythematosus and that this T cell response may mediate epitope spread to autoantibodies in both models.

关键词： β2-glycoprotein I T cells systemic lupus erythematosus autoantibodies MHC class II haplotypes

Adverse impact of industrial animal agriculture on the health and welfare of farmed animals

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Integrative Zoology 2006年第1期1卷 53-58页

作者： joyce D’sILVA Compassion in World Farming PetersfieldHampshireUK

Industrial animal agriculture is grounded in the concept of maximizing productivity and *** breeding for maximum productivity in one characteristic of the animal(*** yield in cows,or breast meat in broiler chickens)has resulted in genotypes and phenotypes that may predispose the animals to poor health and *** conditions in which these individuals are kept may also frustrate many inherited behaviors that they are strongly motivated to *** order to curb the resulting harmful aberrant behaviors,such as feather-pecking in chickens,we sometimes resort to mutilating the *** many places chickens are routinely de-beaked by means of a hot metal *** in World Farming(an international organization that promotes the humane treatment of farm animals)believes that it is unethical to treat sentient beings in such *** have a duty to respect farm animals’sentience by providing them with housing conditions that take their needs and wants into account,and by reverting to the use of dual-purpose,slower-growing breeds that have the potential for good *** to current farming practices are available,and we owe it to the animals,and to our consciences,to pursue them.

关键词： animal welfare intensive animal husbandry selective breeding stereotypic behavior

Mechanical Properties of Polypropylene Composites reinforced with Macadamia Nutshell Fibers

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Journal of renewable Materials 2019年第10期7卷 1047-1053页

作者： joyce de P.Cipriano N.C.Zanini I.r.Dantas D.r.Mulinari Faculdade de Tecnologia/FAT/UErJ Rodovia Presidente Dutra km 298 Polo IndustrialResende27537-000Brazil Universidade Federal Fluminense Avenida dos Trabalhadores420Vila Santa CecíliaVolta Redonda27255-125Brazil

The use of natural fibers as an additive in polymeric matrices has attracted interest of the automotive industries,for its low cost,mechanical properties,biodegradability and ***,the hydrophilic nature of the fiber makes polymer compatibility *** surface treatments can be used to enhance the fiber/matrix *** the present work,polypropylene(PP)composites reinforced with fibers from macadamia nutshell were obtained and *** nutshell fibers were treated by an alkaline treatment with sodium hydroxide(NaOH 4%)to improve adhesion between fibers and *** were characterized by techniques of scanning Electron Microscopy(sEM)and X-ray Diffraction(XrD).The PP was mixed with the macadamia fibers(treated and untreated),in proportions of 5 and 10%(wt/wt)using a thermokinetic *** tensile,flexural and impact specimens(Pure PP and composites)were prepared by an injection molding process and tested for evaluation of mechanical *** results showed that the insertion of treated fibers in the PP matrix increased the stiffness of the ***,the composites reinforced with untreated fibers presented higher impact energy absorption when compared to composites reinforced with treated fibers.

关键词： Macadamia nutshell polypropylene alkaline treatment mechanical properties

subacute fulminant hepatic failure with intermittent fever

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Hepatobiliary & Pancreatic Diseases International 2009年第6期8卷 657-659页

作者： joyce E.Johnson Molecular Infectious Diseases Laboratory and Molecular Epidemiology Medical CenterVanderbilt University

BACKGrOUND: Viral hepatitis B accounts for over 80% of acute hepatic failures in China and the patients die mainly of its complications. A patient with hepatic failure and fever is not uncommon, whereas repeated fever is rare. METHODs: A 32-year-old female was diagnosed with subacute hepatic failure and hepatitis B viral infection because of hyperbilirubinemia, coagulopathy, hepatic encephalopathy, serum anti-HBs-positive without hepatitis B vaccination, and typical intrahepatic pathological features of chronic hepatitis B. Plasma exchange was administered twice and she awoke with hyperbilirubinemia and discontinuous fever. rEsULTs: Urethritis was confirmed and medication-induced fever and/or spontaneous bacterial peritonitis (Gram-negative bacillus infection) was suspected. The patient was treated with antibiotics, steroids and a Chinese herbal medicine, matrine, for three months and she recovered. CONCLUsION: The survival rate of patients with hepatic failure might be improved with comprehensive supporting measures and appropriate, timely management of complications.

关键词： acute hepatic failure intermittent fever plasma exchange matrine

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Do assortative mating and immigrant inviability help maintain population genetic structuring of an herbivore on a crop and a wild relative?

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Insect science 2019年第2期26卷 283-296页

作者： ricardo ramirez-romero Delia Garibay-Benitez Ofelia Vargas-Ponce Andrea joyce Julio s. Bernal Departamento de Produccion Agricola CUCBA Universidad de Guadalajara Zapopan Jalisco Mexico Departamento de Botanica y Zoologia CUCBA Universidad de Guadalajara Zapopan Jalisco Mexico sierra Nevada research Institute University of California Merced California USA Department of Entomology Texas A&M University College Station. Texas USA

Population genetic structuring is common among herbivorous insects and frequently is associated with divergent host plants, such as crops and their wild relatives. Previous studies showed population genetic structuring in corn leafhopper Dulbulus maidis in Mexico, such that the species consists of two sympatric, host plant-associated populations: an abundant and widespread "pestiferous” population on maize (Zea mays mays), and a small and localized "wild" population on perennial teosinte (Zea diploperennis). a maize wild relative with a limited distribution. This study addressed whether assortative mating and immigrant inviability mediate genetic structuring of corn leafliopper by comparing the mating and reproductive successes of pestiferous and wild females that colonize their nonassociated host plants against the successes of females colonizing their associated host plants. Assortative mating was assessed by comparing mating frequencies and premating and mating times among females of each population on each host plant: immigrant inviability was assessed by comparing, across two generations, the fecundity, survival, development time, sex ratio, and population growth rate among leafhopper populations and host plants. Our results showed that on maize, and compared to resident, pestiferous females, wild females were more likely to mate, and greater proportions of their offspring survived to adult stage and were daughters;consequently, the per-generation population growth rate on maize was greater for immigrant, wild leafhoppers compared to resident, pestiferous leafhoppers. Our results suggested that wild leafhoppers emigrating to maize have a fitness advantage over resident, pestiferous leafhoppers, while immigrant pestiferous and resident wild leafhoppers on teosinte have similar fitnesses.

关键词： crop domestication Dalbulus maidis ecological speciation host associated differentiation Zea diploperennis Zea mays mays

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轿车柴油机进气门与座圈磨损机理的研究

汽车与新动力 2000年第4期 34-41页

作者： Lewis r dwyer-joyce r s Josey G 史大德

采用台式试验装置来研究轿车柴油机进气门与座圈的磨损机理,所用的台式试验装置按模拟进气门与座圈的负荷环境和接触条件而设计的。研究表明进气门与座圈的磨损问题包括两种不同的机理:气门关闭时的落座冲击和燃烧压力作用下气门在座圈... 详细信息

采用台式试验装置来研究轿车柴油机进气门与座圈的磨损机理,所用的台式试验装置按模拟进气门与座圈的负荷环境和接触条件而设计的。研究表明进气门与座圈的磨损问题包括两种不同的机理:气门关闭时的落座冲击和燃烧压力作用下气门在座圈上的滑动。研究表明,磨损的主要机理与各种关键的工作状态有关,例如气门的关闭速度、燃烧负荷、气门相对气门座的不对中性以及气门和座圈的材料选择等。

关键词：柴油机汽车发动机气门气门座磨损研究