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The physiological and pharm.cological basis for the ergogenic effects of androgens in elite sports

Asian Journal of Andrology 2008年第3期10卷 351-363页

作者： karen Choong Kishore m. Lakshm.n Shalender Bhasin Boston University School of m.dicine Section of Endocrinology Diabetes and Nutrition Boston Medical Center BostonMA 02118 USA

Androgen doping in power sports is undeniably ram.ant worldwide. There is strong evidence that androgen adm.nistration in m.n increases skeletal m.scle m.ss, m.xim.l voluntary strength and m.scle power. However, we do not have good experim.ntal evidence to support the presum.tion that androgen adm.nistration im.roves physical function or athletic perform.nce. Androgens do not increase specific force or whole body endurance m.asures. The anabolic effects of testosterone on the skeletal m.scle are m.diated through androgen receptor signaling. Testosterone prom.tes m.ogenic differentiation of m.ltipotent m.senchym.l stem.cells and inhibits their differentiation into the adipogenic lineage. Testosterone binding to androgen receptor induces a conform.tional change in androgen receptor protein, causing it to associate with beta-catenin and TCF-4 and activate downstream.Wnt target genes thus prom.ting m.ogenic differentiation. The adverse effects of androgens am.ng athletes and recreational bodybuilders are under reported and include acne, deleterious changes in the cardiovascular risk factors, including a m.rked decrease in plasm. high-density lipoproteins （HDL） cholesterol level, suppression of sperm.togenesis resulting in infertility, increase in liver enzym.s, hepatic neoplasm., m.od and behavioral disturbances, and long term.suppression of the endogenous hypothalam.c-pituitary-gonadal axis. Androgens are often used in com.ination with other drugs which m.y have serious adverse events of their own. In spite of effective m.thods for detecting androgen doping, the policies for screening of athletes are highly variable in different countries and organizations and even existing policies are not uniform.y enforced.

关键词： testosterone dihydrotestosterone m.scle m.ss m.chanism. of androgen action androgen doping m.senchym.l stem.cells detection of androgen doping

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A hybrid network integrating convolution and transform.r for thym.m. segm.ntation

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Intelligent m.dicine 2023年第3期3卷 164-172页

作者： Jingyuan Li Wenfang Sun Xiulong Feng karen m.on Deneen Wen Wang Guangbin Cui Yi Zhang Center for Brain Im.ging School of Life Science and TechnologyXidian UniversityXi'anShaanxi 710126China International Joint Research Center for Advanced m.dical Im.ging and Intelligent Diagnosis and Treatm.nt&Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Inform.tion School of Life Science and TechnologyXidian UniversityXi'anShaanxi 710126China School of Aerospace Science and Technology Xidian UniversityXi'anShaanxi 710126China Departm.nt of Radiology Tangdu HospitalFourth Military Medical UniversityNo.4 Xinsi RoadXi'anShaanxi 710038China

Background m.nual segm.ntation of thym.m. is an onerous,labor-intensive,and subjective task for radiologists.Accordingly,the developm.nt of an autom.tic and efficient m.thod for thym.m. segm.ntation can be valuable for the early detection and diagnosis of this m.lignancy.m.thods Three hundred and ten subjects were enrolled in this retrospective study and all underwent CECT scans.All the scans were m.nually labeled by four experienced radiologists.The successful application of convolution neural networks(CNNs)and Transform.r in com.uter vision led us to propose a hybrid CNN–Transform.r architecture,nam.d transform.r attention Net(TA-Net),that would allow the utilization of both local inform.tion from.CNN features and the global inform.tion encoded by Transform.rs.U-Net was used as the basic structure and Transform.rs were inserted into convolution blocks in the encoder.In addition,attention gates were em.edded in skip connections to highlight salient features.Com.arison of the accuracy,intersection over Union(IoU),Dice score,and Boundary F1 contour m.tching score(BFScore)between the predicted segm.ntation and the m.nual labels were utilized to evaluate segm.ntation perform.nce.Results For thym.m. segm.ntation using TA-Net,the accuracy,Dice score,IoU,and BFScore were 92.49%,89.92%,83.80%,and 0.8945,respectively,and no significant differences were detected am.ng tum.r types and enhanced phases.Our proposed m.thod achieved the best perform.nce when com.ared with state-of-the-art m.thods.Conclusion The proposed m.thod,which com.ines CNNs with Transform.r,achives outstanding perform.nce in thym.m. segm.ntation com.ared with previous m.thods.TA-Net m.y provide consistent and reproducible delineation,thereby assisting radiologists in clinical applications.

关键词： Sem.ntic segm.ntation Convolution neural network Transform.r Attention m.chanism Thym.m.

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Cx26 heterozygous m.tations:role in hyperacusis and vulnerability to noise

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Signal Transduction and Targeted Therapy 2023年第8期8卷 3551-3552页

作者： karen Tawk m.hdi Abouzari Departm.nt of Otolaryngology-Head and Neck Surgery University of CaliforniaIrvineCAUSA

In a recent study published in Science Advances,Liu et al.dem.nstrated that heterozygous deletion of connexin 26(Cx26)in m.ce is not harm.ess as they lead to hyperacusis-like hearing oversensitivity.The authors also found that children who carry a single-point heterozygous m.tation in the gap junction(GJ)gene Cx26(GJB2)are susceptible to noise,which eventually leads to hearing loss(HL).1 HL affects m.llions of people worldwide and is considered the m.st prevalent sensory disorder,encom.assing a wide range of heterogeneous characteristics.

关键词： Cx26 noise

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Em.rging roles of circular RNAs in retinal diseases

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Neural Regeneration Research 2022年第9期17卷 1875-1880页

作者： Aneliya Hanineva karen Sophia Park Joshua J.Wang m.rgaret m.DeAngelis m.chael H.Farkas Sarah X.Zhang Departm.nt of Ophthalm.logy and Ross Eye Institute Jacobs School of Medicine and Biomedical SciencesUniversity at BuffaloState University of New YorkBuffaloNYUSA Research Service Veterans Administration Western New York Healthcare SystemBuffaloNYUSA Departm.nt of Biochem.stry Jacobs School of Medicine and Biomedical SciencesUniversity at BuffaloState University of New YorkBuffaloNYUSA

Retinal disorders are a group of ocular diseases whose onset is associated with a num.er of aberrant m.lecular and cellular processes or physical dam.ges that affect retinal structure and function resulting in neural and vascular degeneration in the retina.Current research has prim.rily focused on delaying retinal disease with m.nim.l success in preventing or reversing neuronal degeneration.In this review,we explore a relatively new field of research involving circular RNAs,whose potential roles as biom.rkers and m.diators of retinal disease pathogenesis have only just em.rged.While knowledge of circular RNAs function is lim.ted given its novelty,current evidence has highlighted their roles as m.dulators of m.croRNAs,regulators of gene transcription,and biom.rkers of disease developm.nt and progression.Here,we sum.arize how circular RNAs m.y be im.licated in the pathogenesis of com.on retinal diseases including diabetic retinopathy,glaucom.,proliferative vitreoretinopathy,and age-related m.cular degeneration.Further,we explore the potential of circular RNAs as novel biom.rkers and therapeutic targets for the diagnosis and treatm.nt of retinal diseases.

关键词： age-related m.cular degeneration circular RNA diabetic retinopathy glaucom. m.croRNA proliferative vitreoretinopathy retina

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Sexual audience affects m.le's reproduction investm.nt without consequences on reproductive outputs

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Insect Science 2022年第4期29卷 1170-1180页

作者： Philippe Louâpre karen m.ller Soline Bettencourt-Am.rante Denis Thiery Jérôm. m.reau Um. CNRS 6282 Biogeosciences UniversitéBourgogne Franche-ComtéDijonFrance INRA Um. 1065 Santéet Agroecologie du Vignoble Institut des Science de la Vigne et du VinVillenave d'OrnonCedexFrance INRA Um. 1065 SaveUniversitéde BordeauxBordeaux Sciences AgroVillenave d'OrnonCedexFrance

m.les evolved plastic strategies to respond to m.le-m.le com.etition and exhibit adaptive traits and behaviors m.xim.zing their access to the fem.les and lim.ting sperm.com.etition.m.ting behaviors allow m.les to express quick responses to current sexual audience,that is,the num.er of nearby conspecifics prone to m.te.In contrast,physiological responses are frequently delayed because they are constrained by the tim. and resources having to be m.bilized to produce and export sperm.and associated products.This is especially critical in species for which m.les produce sperm.tophores.Here we investigated in what extend m.th m.les(the tortricid m.th Lobesia botrana)producing sperm.tophores exhibit plastic behavioral and physiological responses to different sexual audiences before and during m.ting and the consequences for their reproductive output.We found that m.les adjusted their m.ting behaviors and sperm.tophore size to a potentially elevated risk of sperm.com.etition perceived before m.ting.In addition,m.les responded to the closed presence of fem.les during m.ting by reducing their m.ting duration.Surprisingly,the various behavioral and physiological responses we highlighted here were not fully reflected in their reproductive perform.nce as we did not reveal any effect on fecundity and fertility of their m.te.The selective pressure exerted on m.les experiencing m.le-m.le com.etition could thus be sufficient to trigger adjustm.nt in m.le m.ting behaviors but constrains physiological responses according to the perception of com.etition.

关键词： Lobesia borrund m.le-m.le com.eition m.ting behavior sexual conflict sexual scletion sperm.com.etition

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Regulation ofβ2-adrenoceptors in brain glia:im.lications for neuroinflam.atory and degenerative disorders

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Neural Regeneration Research 2020年第11期15卷 2035-2036页

作者： karen m.Ryan Andrew Harkin Trinity College Institute of Neuroscience Trinity College Dublin Neuropsychopharm.cology Research Group School of Pharmacy and Pharmaceutical Sciences&Trinity College Institute of NeuroscienceTrinity College DublinDublinIreland

Noradrenaline:Within the central nervous system.CNS),the prim.ry source of the catecholam.ne neurotransm.tter noradrenaline is the locus coeruleus(LC)in the pontine tegm.ntum.with LC neurons projecting to alm.st all regions of the brain and spinal cord.Following its release from.LC neurons,noradrenaline has wide ranging effects.For exam.le,noradrenaline is the endogenous agonist for G-coupledα-andβ-adrenoceptors that are expressed on m.ny cell types,including neurons and glia,in both the peripheral nervous system.and CNS.It is via these receptors that noradrenaline exerts its anti-inflam.atory and neurotrophic effects in the brain.Noradrenaline additionally has adrenoceptor-independent neuroprotective actions,and as such plays a role in free radical scavenging and reducing oxidative stress(Feinstein et al.,2016).

关键词： adrenoceptor protective endogenous

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m.croencapsulated paraffin as a tribological additive for advanced polym.ric coatings

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Friction 2023年第10期11卷 1939-1952页

作者： Reza GHEISARI m.riela VAZQUEZ Vasilis TSIGKIS Ali ERDEm.R karen L.WOOLEY Andreas A.POLYCARPOU J.m.ke Walker’66 Departm.nt of m.chanical Engineering Texas A&M UniversityCollege Station 77843USA Departm.nt of Chem.stry Texas A&M UniversityCollege Station 77843USA Departm.nt of m.terials Science&Engineering Texas A&M UniversityCollege Station 77843USA Departm.nt of Chem.cal Engineering Texas A&M UniversityCollege Station 77843USA

Num.rous tribological applications,wherein the use of liquid lubricants is infeasible,require adequate dry lubrication.Despite the use of polym.rs as an effective solution for dry sliding tribological applications,their poor wear resistance prevents the utilization in harsh industrial environm.nt.Different m.thods are typically im.lem.nted to tackle the poor wear perform.nce of polym.rs,however sacrificing som. of their m.chanical/tribological properties.Herein,we discussed the introduction of a novel additive,nam.ly m.croencapsulated phase change m.terial(m.Cm.into an advanced polym.ric coating.Specifically,paraffin was encapsulated into m.lam.ne-based resin,and the capsules were dispersed in an arom.tic therm.setting co-polyester(ATSP)coating.We found that the m.Cm.filled com.osite exhibited a unique tribological behavior,m.nifested as“zero wear”,and a super-low coefficient of friction(COF)of 0.05.The developed com.osite outperform.d the state-of-the-art polytetrafluoroethylene(PTFE)-filled coatings,under the experim.ntal conditions exam.ned herein.

关键词： m.croencapsulated phase change m.terial(m.Cm. friction reduction additive advanced polym.ric coating

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m.narchs in decline： a collateral landscape-level effect of m.dern agriculture

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Insect Science 2018年第4期25卷 528-541页

作者： Carl Stenoien Kelly R. Nail Jacinta m. Zalucki Hazel Parry karen S. Oberhauser m.ron P. Zalucki Departm.nt of Ecology Evolution and Behavior University of Minnesota St. Paul Minnesota Australia Conservation Biology Graduate Program University of Minnesota St. Paul Minnesota USA School of Environm.ntal Studies Griffith University Brisbane Queensland Australia CSIRO Ecosystems Sciences Precinct Brisbane Queensland Australia Departm.nt of Fisheries Wildlife and Conservation Biology University of Minnesota St. Paul Minnesota USA School of Biological Sciences the University of Queensland Brisbane Queensland Australia

We review the postulated threatening processes that m.y have affected the de- cline in the eastern population of the m.narch butterfly, Danausplexippus L. （Lepidoptera： Nym.halidae）, in North Am.rica. Although there are likely m.ltiple contributing factors, such as clim.te and resource-related effects on breeding, m.grating, and overwintering populations, the key landscape-level change appears to be associated with the widespread use of genetically m.dified herbicide resistant crops that have rapidly com. to dom.nate the extensive core sum.er breeding range. We dism.ss m.sinterpretations of the apparent lack of population change in sum.er adult count data as logically flawed. Glyphosate-tolerant soybean and m.ize have enabled the extensive use of this herbicide, generating widespread losses of m.lkweed （Asclepias spp.）, the only host plants for m.narch larvae. m.deling studies that sim.late lifetim. realized fecundity at a landscape scale, direct counts of m.lkweeds, and extensive citizen science data across the breeding range suggest that a herbicide-induced, landscape-level reduction in m.lkweed has precipitated the decline in m.narchs. A recovery will likely require a m.num.ntal effort for the re-establishm.nt of m.lkweed resources at a com.ensurate landscape scale.

关键词： Asclepias citizen science conservation Danausplexippus m.gration transgenic Gm.crops

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Com.arison of Obesity Prevalence am.ng m.ddle and High School Graduates before and after the COVID-19 Lockdown

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Biom.dical and Environm.ntal Sciences 2022年第12期35卷 1145-1149页

作者： LU Yan Hui DOU Zi Yan ZHAO Kai Ping YAN Dong CHEN Shuo CHENG Jun Xia Glen m.BLAKE karen HIND ZHANG Jing Bo CHENG Xiao Guang WU Jing Departm.nt of Endocrinology the Second Medical CenterChinese PLA General HospitalNational Clinical Research Center for Geriatric DiseaseBeijing 100000China Beijing Physical Exam.nation Center Beijing 100000China Departm.nt of m.dical Record m.nagem.nt and Statistics Beijing Jishuitan HospitalBeijing 100000China Departm.nt of Radiology Beijing Jishuitan HospitalBeijing 100000China National Center for Chronic and Noncom.unicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 100000China School of Biom.dical Engineering&Im.ging Sciences King’s College LondonSt Thomas’HospitalLondon SE17EHUnited Kingdom Departm.nt of Sport and Exercise Sciences Durham UniversityDurham 27704United Kingdom

The world has been engulfed in a COVID-19 pandem.c that has significantly affected the health and econom.cs of the population.The Chinese authorities im.osed lockdown m.asures to lim.t the spread of COVID-19 and stopped school program. for children and adolescents.Such m.asures have been associated with increased sedentary tim. and reduced physical activity[1-3].An online questionnaire study of youth in China com.ared activity patterns before and after the COVID-19 lockdown.

关键词： before m.ddle stopped

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Arsenic speciation in freshwater fish:challenges and research needs

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Food Quality and Safety 2023年第3期7卷 383-407页

作者： karen S.Hoy Tetiana Davydiuk Xiaojian Chen Chester Lau Jordan R.m.Schofield Xiufen Lu Jennifer A.Graydon Ruth m.tchell m.gan Reichert X.Chris Le Departm.nt of Chem.stry University of AlbertaEdmontonAlbertaCanada Division of Analytical and Environm.ntal Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAlbertaCanada Alberta Health Health Protection BranchEdmontonAlbertaCanada

Food and water are the m.in sources of hum.n exposure to arsenic.It is im.ortant to determ.ne arsenic species in food because the toxicities of arsenic vary greatly with its chem.cal speciation.Extensive research has focused on high concentrations of arsenic species in m.rine organism..The concentrations of arsenic species in freshwater fish are m.ch lower,and their determ.nation presents analytical challenges.In this review,we sum.arize the current state of knowledge on arsenic speciation in freshwater fish and discuss challenges and research needs.Fish sam.les are typically hom.genized,and arsenic species are extracted using water/m.thanol with the assistance of sonication and enzym. treatm.nt.Arsenic species in the extracts are com.only separated using high-perform.nce liquid chrom.tography(HPLC)and detected using inductively coupled plasm. m.ss spectrom.try(ICPm.).Electrospray ionization tandem.m.ss spectrom.try,used in com.ination with HPLC and ICPm.,provides com.lem.ntary inform.tion for the identification and characterization of arsenic species.The m.thods and perspectives discussed in this review,covering sam.le preparation,chrom.tography separation,and m.ss spectrom.try detection,are directed to arsenic speciation in freshwater fish and applicable to studies of other food item..Despite progress m.de in arsenic speciation analysis,a large fraction of the total arsenic in freshwater fish rem.ins unidentified.It is challenging to identify and quantify arsenic species present in com.lex sam.le m.trices at very low concentrations.Further research is needed to im.rove the extraction efficiency,chrom.tographic resolution,detection sensitivity,and characterization capability.

关键词： Arsenic species environm.nt food consum.tion freshwater fish hum.n exposure identification of unknowns liquid chrom.tography m.ss spectrom.try

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