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非传统晶体生长的早期观察

中国科学：化学 2012年第1期42卷 74-83页

作者： greer heather f.于丰娇周午纵 EaStChem School of ChemistryUniversity of St Andrews

晶体早期生长的研究揭示,在某些体系中,晶体生长可能并不遵循传统路径.借由某些聚合物或生物分子的帮助,无机晶体的前驱体或纳米晶体在生长初期有可能聚集为无序的大块颗粒.这些聚集体表面晶化形成高结晶度高密度的外壳,随后完成从表面... 详细信息

晶体早期生长的研究揭示,在某些体系中,晶体生长可能并不遵循传统路径.借由某些聚合物或生物分子的帮助,无机晶体的前驱体或纳米晶体在生长初期有可能聚集为无序的大块颗粒.这些聚集体表面晶化形成高结晶度高密度的外壳,随后完成从表面到核心的晶化过程.此逆向晶体生长机理在一些诸如沸石、钙钛矿、金属和金属氧化物等无机化合物体系中均已被发现,在其他材料体系里也将得到验证.认识这一新的晶体生长路径将给予我们更多的自由度来实现晶体形态控制,也有助于我们对于许多天然矿物形成机制的理解.本文简要回顾了最近本领域研究中一些典型逆向晶体生长的例子.

关键词：逆向晶体生长空心晶体核壳结构颗粒电子显微镜

A Role f.r Histone Chaperones in Regulating RNA Polymerase II

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Advances in Biological Chemistry 2015年第2期5卷 35-44页

作者： JoDi Lynn Osborn Susanna f. greer Department of.Biology Georgia State University Atlanta USA

Transcription is a highly regulated cellular process in which dysf.nction leads to disease. One level of.regulation is chromatin structure which protects promoters f.om transcription f.ctor binding. To circumvent this blockade, histone chaperones aid in displacement of.nucleosomes. In particular, the histone chaperone complex HUCA, consisting of.Hira, Ubn1, Cabin1, and ASf.a, replaces histone variant H3.1 with H3.3 in f.ont of.actively transcribing RNA Polymerase II (RNAPII). The 26S proteasome is a major degrader of.proteins within the cell and plays both proteolytic and non- proteolytic roles in transcriptional regulation. One major role is the degradation of.irreversibly arrested RNAPII. Several interactions between HUCA, the 26S proteasome, and RNAPII have been characterized individually;we now present observations f.om our lab and others which directly associate elongating RNAPII with the degradation machinery through observations of.involvement with the HUCA complex. Our short report presents these ideas and discusses their importance in transcriptional regulation as well as implications in disease manif.station.

关键词： Histone Chaperones RNA Polymerase II 26S Proteasome Transcriptional Regulation

Analysis of.gateroad stability at two longwall mines based on f.eld monitoring results and numerical model analysis

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International Journal of.Mining Science and Technology 2019年第1期29卷 35-43页

作者： Gabriel S.Esterhuizen David f.Gearhart Ted Klemetti heather Dougherty Mark van Dyke National Institute f.r Occupational Saf.ty and Health

Coal mine longwall gateroads are subject to changing loading conditions induced by the advancing longwall f.ce. The ground response and support requirements are closely related to the magnitude and orientation of.the stress changes, as well as the local geology. This paper presents the monitoring results of.gateroad response and support perf.rmance at two longwall mines at a 180-m and 600-m depth of.*** the f.rst mine, a three-entry gateroad layout was used. The second mine used a f.ur-entry, yieldabutment-yield gateroad pillar system. Local ground def.rmation and support response were monitored at both sites. The monitoring period started during the development stage and continued during f.rst panel retreat and up to second panel retreat. The two data sets were used to compare the response of.the entries in two very dif.erent geotechnical settings and dif.erent gateroad layouts. The monitoring results were used to validate numerical models that simulate the loading conditions and entry response f.r these widely dif.ering conditions. The validated models were used to compare the load path and ground response at the two mines. This paper demonstrates the potential f.r numerical models to assist mine engineers in optimizing longwall layouts and gateroad support systems.

关键词： Coal mining Longwall Gateroad Support Numerical models

Assessing support alternatives f.r longwall gateroads subject to changing stress

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International Journal of.Mining Science and Technology 2021年第1期31卷 103-110页

作者： Gabriel S.Esterhuizen I.Berk Tulu Dave f.Gearhart heather Dougherty Mark Van Dyke National Institute f.r Occupational Saf.ty and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA West Virginia University MorgantownWV 26506USA

Longwall gateroad entries are subject to changing horizontal and vertical stress induced by redistribution of.loads around the extracted *** stress changes can result in signif.cant def.rmation of.the entries that may include roof.sag,rib dilation,and f.oor *** operators install dif.erent types of.supports to control the ground response and maintain saf. access and ventilation of.the longwall *** paper describes recent research aimed at quantif.ing the ef.ect of.longwall-induced stress changes on ground stability and using the inf.rmation to assess support *** research included monitoring of.ground and support interaction at several operating longwall mines in the U.S.,analysis and calibration of.numerical models that adequately represent the bedded rock mass,and observation of.the support systems and their response to changes in *** models were then used to investigate the impact of.geology and stress conditions on ground def.rmation and support response f.r various depths of.cover and geologic *** research results were summarized in two regression equations that can be used to estimate the likely roof.def.rmation and height of.roof.yield due to longwall-induced stress *** inf.rmation is then used to assess the ability of.support systems to maintain the stability of.the *** application of.the method is demonstrated with a retrospective analysis of.the support perf.rmance at an operating longwall mine that experienced a headgate roof.*** method is shown to produce realistic estimates of.gateroad entry stability and support perf.rmance,allowing alternative support systems to be assessed during the design and planning stage of.longwall operations.

关键词： Longwall Gateroad Support design Coal Standing support

Novel heating-and def.rmation-induced phase transitions and mechanical properties f.r multicomponent Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=f.,Co,Ni,Cu)amorphous alloys

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Journal of.Materials Science & Technology 2022年第9期104卷 109-118页

作者： J.Ding A.Inoue f.L.Kong S.L.Zhu Y.L.Pu E.Shalaan A.A.Al-Ghamdi A.L.greer School of.Materials Science and Engineering Tianjin UniversityTianjin 300072China International Institute of.Green Materials Josai International UniversityTogane 283-8555Japan Institute of.Massive Amorphous Alloy Science China University of Mining TechnologyXuzhou 221116China Department of.Physics King Abdulaziz UniversityJeddah 22254Saudi Arabia MISiS National University of Science and TechnologyMoscow 119049Russia School of.Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Department of.Materials Science and Metallurgy University of CambridgeCambridge CB30FSUK

Multicomponent alloys of.Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=f.,Co,Ni,Cu)can be melt-spun to obtain amorphous *** maximum thickness f.r f.lly amorphous ribbons varies with composition in the range 34-53μ*** contrast,f.lly amorphous ribbons are not obtainable f.r binary Zr_(50)Ni_(50)or ternary Zr_(50)(Ni,Cu)_(50)***-induced crystallization occurs through:two stages of.amorphous[am]→[~(am')+B2]→[B2+B33]f.r Zr_(50)M_(50);and[am]→[am'+B2]→[B2+AgZr]f.r Zr_(50)(M,Ag)_(50);and a single stage of.am]→[B2]f.r Zr_(50)(M,Pd)_(50),while no B2 phase is f.rmed f.r the binary and ternary Zr_(50)Q_(50)(Q=Ni or/and Cu)***-spun amorphous ribbons have good bending ***,Zr_(50)M_(50)ribbons in tension show 0.22-0.28%plastic elongation and work-hardening(the yield stress is~820 MPa,the f.acture stress is~1200 MPa).When cold-rolled at room temperature to 30%reduction in thickness,Zr_(50)M_(50)ribbons show 10%increase in hardness,while retaining good bending ***-rolling induces precipitation of.spheroidal B2 and irregular B33 particles,while def.rmation in tension induces B2,B33 and also plate-like monoclinic *** B2 and B33 particles f.rm by polymorphic transf.rmation,and include a high density of.internal *** novel def.rmationinduced precipitation has not been recognized f.r any Zr_(50)Q_(50)binary or ternary *** new multicomponent systems are encouraging f.r f.ture progress as structural amorphous alloys.

关键词： Multicomponent Microstructure Mechanical properties Phase transition Amorphous alloy

Canine on the Couch:The New Canary in the Coal Mine f.r Environmental Health Research

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Environment & Health 2024年第8期2卷 517-529页

作者： Catherine f.Wise Matthew Breen heather M.Stapleton Nicholas School of.the Environment Duke UniversityDurhamNorth Carolina 27708United States Duke Cancer Institute DurhamNorth Carolina 27710United States Department of.Molecular Biomedical Sciences College of Veterinary MedicineNorth Carolina State University1060 William Moore DriveRaleighNorth Carolina 27607United States Comparative Medicine Institute North Carolina State UniversityRaleighNorth Carolina 27607United States Center f.r Human Health and the Environment North Carolina State UniversityRaleighNorth Carolina 27607United States

Human health is intimately connected and tied to the health of.our environment and ecosystem,with only a very small f.action of.the risk f.r chronic diseases explained by genetics *** animals are prone to disease types that are shared with people,including cancers and endocrine disorders,reinf.rcing the thought that environmental f.ctors contribute to the risks f.r chronic *** f.ctors include air and water pollution and the built *** such,there is increasing interest in pursuing research with companion animals,and specif.cally dogs,as sentinel species to inf.rm comparative health assessments and identif. risk f.ctors f.r *** the canine diseases f.r which environmental exposure research has been published,cancers have received the most *** review summarizes two main aspects of.this comparative approach:(1)cancers that occur in dogs and which are similar to humans and(2)research investigating environmental exposures and health outcomes in *** goal of.this review is to highlight the diverse conditions in which pet dogs may provide unique perspectives and advantages to examine relationships between environmental exposures and health outcomes,with an emphasis on chemical pollution and ***,this review seeks to raise awareness and stimulate discussion around the best practices f.r the use of.companion animals as environmental health sentinels.

关键词： sentinels dogs environmental health comparative oncology cancer alternative models environmental exposure

The benef.ts of.neuroinf.ammation f.r the repair of.the injured central nervous system

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Cellular & Molecular Immunology 2019年第6期16卷 540-546页

作者： heather Y.f.Yong Khalil S.Rawji Samira Ghorbani Mengzhou Xue V.Wee Yong University of.Calgary CalgaryCanada The Second Af.iliated Hospital of.Zhengzhou University ZhengzhouChina

Inf.ammation of.the nervous system(neuroinf.ammation)is now recognized as a hallmark of.virtually all neurological *** neuroinf.ammatory conditions such as multiple sclerosis,there is prominent inf.ltration and a long-lasting representation of.various leukocyte subsets in the central nervous system(CNS)*** in classic neurodegenerative disorders,where such immense inf.ammatory inf.ltrates are absent,there is still evidence of.activated CNS-intrinsic *** consequences of.excessive and uncontrolled neuroinf.ammation are injury and death to neural elements,which manif.st as a heterogeneous set of.neurological ***,it is now readily acknowledged,due to instructive studies f.om the peripheral nervous system and a large body of.CNS literature,that aspects of.the neuroinf.ammatory response can be benef.cial f.r CNS *** recognized benef.ts of.inf.ammation to the CNS include the preservation of.CNS constituents(neuroprotection),the prolif.ration and maturation of.various neural precursor populations,axonal regeneration,and the ref.rmation of.myelin on denuded ***,we highlight the benef.ts of.neuroinf.ammation in f.stering CNS recovery af.er neural injury using examples f.om multiple sclerosis,traumatic spinal cord injury,stroke,and Alzheimer’s *** f.cus on CNS regenerative responses,such as neurogenesis,axonal regeneration,and remyelination,and discuss the mechanisms by which neuroinf.ammation is pro-regenerative f.r the ***,we highlight treatment strategies that harness the benef.ts of.neuroinf.ammation f.r CNS regenerative responses.

关键词： inf.ammation benef.ts instru

The Ef.ect of.an Acute f.rmers Walk Exercise Bout on Muscle Damage and Recovery in Recreationally Trained Adults

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Journal of.Science in Sport and Exercise 2022年第2期4卷 156-167页

作者： Jeb f.Struder Daniel E.Newmire Mikaela D.Boham heather E.Webb Department of.Kinesiology Korey Stringer InstituteUniversity of ConnecticutStorrsCT 06269USA Exercise Physiology and Biochemistry Laboratory Department of KinesiologyTexas A&M University-Corpus ChristiCorpus ChristiTX 78412USA Department of.Kinesiology Mercer UniversityAtlantaGA 30341USA

Purpose The f.rmer’s Walk(f.)may supplement resistance training through f.nctional tasks like lif.ing and carrying weight over various *** inf.rmation exists concerning the intramuscular responses resulting f.om f. per-f.rmance,possibly impacting its application in exercise ***,the purpose of.the study was to investigate Creatine Kinase(CK)and myoglobin(Mb)responses f.llowing the f.rmers Walk Condition(f.C)compared to a control protocol(NWC).Methods f.f.een participants(Mean±SEM;age:21.6±0.5 years;height:172.5±2.4 cm;body weight:81.8±4.0 kg)completed an initial session to measure body composition,lower body power,and *** then completed two counter-balanced exercise protocols consisting of.a 20-m walk perf.rmed within 5 sets of.2 repetitions while either carrying weight(f.C;average wt:85.15±25.55 kg)or not(NWC)with collection of.Visually Perceived Muscle Soreness(VPMS),Ratings of.Perceived Exertion(RPE),and blood ***,blood samples,and Countermovement Jump(CMJ)height were also collected during recovery f.om each exercise protocol with signif.cance of.Pf.cant dif.erences were observed between exercise protocols perf.rmed including participant RPE(Pf.cant dif.erences were noted f.r Mb or CMJ *** Training variables implemented during the f.C may have indirectly minimized muscle damage and neuro-muscular inhibitions in *** participants reported mild soreness,the negligible physiological damage suggests the f.C is a saf. and appropriate f.nctional movement exercise.

关键词： Creatine Kinase f.nctional Exercise Myoglobin Soreness Strongman Training

Southeast Asian primate communities:the ef.ects of.ecology and Pleistocene ref.ges on species richness

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Integrative Zoology 2013年第4期8卷 417-426页

作者： heather HASSEL-f.NNEGAN Carola BORRIES Qing ZHAO Phaivanh PHIAPALATH Andreas KOENIG Department of.Anthropology Stony Brook UniversityStony BrookNYUSA Biology Department Swarthmore CollegeSwarthmorePAUSA College of.Lif. Science Peking UniversityBeijingChina International Union f.r Conservation of.Nature VientianeLao PDR

We examined historical and ecological f.ctors af.ecting current primate biodiversity in Southeast *** Af.ica,Madagascar and South America,but not Southeast Asia,primate species richness is positively associated with average rainf.ll and distance f.om the equator(latitude).We predicted that Southeast Asia’s non-conf.rmance may be due to the ef.ect of.dispersed Pleistocene ref.ges(locations of.constricted tropical f.rests during glacial maxima which today are at least 305 m in altitude).Based on 45 f.rested sites(13 on large islands;32 on the mainland)of.at least 100 km^(2) to minimize recent human impact,we determined correlations between extant primate species richness and rainf.ll,latitude and supplementary ecological variables,while controlling f.r ref.ges and *** f.und that ref.ge sites had signif.cantly higher primate species richness than non-ref.ges(t=-2.76,Pf.om the nearest Pleistocene ref.ge was negatively correlated with species richness f.r non-ref.ge sites(r=-0.51,Pf.erence in species richness between sites on large islands and the mainland(t=-1.4,P=0.16).The expected positive relationship between rainf.ll and species richness was not f.und(r=0.17,P=0.28).As predicted,primate species richness was negatively correlated with latitude(r=-0.39,Pf.(1,38)=6.18,Pf.ge classif.cation(f.(1,42)=5.96,Pf.species *** ecological and historical f.ctors contribute to present day primate species richness in Southeast Asia,making its biodiversity less of.an outlier than previously believed.

关键词： allopatric speciation island latitude mainland rainf.ll temperature