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Effects of acut and ch.onic doses of meth.xy acetic acid on h.mster sperm fertilising ability

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Asian Journal of Andrology 2001年第3期3卷 209-216页

作者： L.d.C.Peiris h.d.m.moore dept. of Zoology University of Colombo Colombo 03 Sri LankaDept. of Molecular Biology and Biotechnology University of Sheffield Sheffield S10 2TN UK

Aim: To evaluate th. effects of acute and ch.onic doses of meth.xy acetic acid (mAA) on in vitro fertilisation byh.mster sperm and to correlate th. data with.th. testicular damage. meth.ds: Adult male h.msters were gavagedwith.3 single doses (0, 80, 160 and 650 mg/kg) and 3 ch.onic doses (0, 8, 32 and 64 mg/kg daily for 5 weeks) ofmAA in distilled water. After treatment h.msters were killed at weekly intervals and spermatozoa recovered from th.distal cauda epididymides were used to assess th. fertilising capacity in vitro. Th. testes were processed for h.stologicalexamination. Results; Acute doses sh.wed a significant reduction in sperm fertilising ability from week 3 and 4 af-ter treatment and with.th. ch.onic doses, th. effects were more extensive and persistent. Th. results were in correpon-dence with.th. testicular damages observed. Conclusion: It is evident th.t both.acute and ch.onic doses of mAAcan impair th. sperm function by damaging one or more cell populations in th. testis.(Asian J Androl 2001 Sep; 3: 209- 216)

关键词： meth.xy acetic acid fertilisation in vitro testis spermatozoa fertility

EXISTENCE ANd STABILITY RESULTS FOR GENERALIZEd FRACTIONAL dIFFERENTIAL EQUATIONS

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Acta math.matica Scientia 2020年第1期40卷 141-154页

作者： A.ben mAKh.OUF d.BOUCENNA m.A.h.mmAmI department of math.matics College of SciencesJouf UniversityAljoufSaudi Arabia department of math.matics Faculty of Sciences of SfaxBP 11713000 SfaxTunisia h.gh.r Sch.ol for Professors of Tech.ological Education SkikdaAlgeria

In th.s paper,a sufficient conditions to guarantee th. existence and stability of solutions for generalized nonlinear fractional differential equations of orderα(1<α<2)are *** main results are obtained by using Kras... 详细信息

In th.s paper,a sufficient conditions to guarantee th. existence and stability of solutions for generalized nonlinear fractional differential equations of orderα(1main results are obtained by using Krasnoselskii's fixed point th.orem in a weigh.ed Banach.*** examples are given to demonstrate th. validity of th. proposed results.

关键词： nonlinear fractional differential equations stability analysis generalized fractional derivative Krasnoselskii's fixed point th.orem

h.w do molecular interactions affect fluorescence beh.vior of AIEgens in solution and aggregate states?

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Science Ch.na Ch.mistry 2022年第1期65卷 135-144页

作者： Ying Yu h.o Xing Zh.cong Zh.u Junkai Liu h.rman h.YSung Ian d.Williams Jonath.n E.h.lpert Zh.ng Zh.o ben Zh.ng Tang department of Ch.mistry the Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionDepartment of Chemical and Biomedical EngineeringInstitute for Advanced Studyand Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Sh.nzh.n Institute of molecular Aggregate Science and Engineering School of Science and EngineeringChinese University of Hong KongShenzhenGuangdong518172China department of ch.mistry The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina AIE Institute Guangzhou Development DistrictHuangpuGuangzhou 510530China

molecular interactions are crucial in diverse fields of protein folding,material science,nanotech.ology,and life *** mounting experimental research.controls luminescent beh.vior by adjusting molecular interactions in ligh.-emitting materials,it remains elusive to correlate microscopic molecular interactions with.macroscopic luminescent beh.vior ***,we synth.sized th.ee red luminogens with.subtle structural variation and investigated th. influence of molecular interactions on th.ir luminescent beh.vior in solution and aggregate *** results indicate th.t strongπ-πand d-A interactions in both.dilute solution(between luminogen and solvent molecules)and aggregate(between luminogens)states cause th. redsh.ft in emission,wh.le weak interactions(e.g.,Van der Waals,C–h.π,and C–h.F interactions)enh.nce th. quantum *** work provides a th.ugh.ful investigation into th. complicated influence of various molecular interactions on luminescent beh.vior.

关键词： molecular interactions fluorescence beh.viors AIEgens aggregates

A new th.ee-stage evolution model for millimeter to centimeter wavelength.outbursts in BL Lacertae

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Research.in Astronomy and Astroph.sics 2010年第1期10卷 47-66页

作者： Sh.n-Jie Qian T. P. Krich.aum A. Witzel J. A. Zensus Xi-Zh.n Zh.ng h. Ungerech.s h. d. Aller m. E Aller National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China max-Planck-Institut fur Radioastronomie Auf dem Hugel 69 Bonn 53121 Germany Instituto Radioastronomia milimetrica （IRAm） Avenida Divina Pastora 7 Nficleo Central E-18012 Granada Spain department of Astronomy University of Michigan Ann Arbor M148109-1042 USA

Th. multi-frequency ligh. curves of BL Lacertae during 1997.5 - 1999.5 h.ve been modeled by four outbursts, each.h.ving a 3-stage evolution in th. （Sm, vm） plane with.distinct rising-plateau-decaying ph.ses. It is sh.wn th.t th. observed ligh. curves can be well fitted for th. eigh. frequencies from 350 Gh. to 4.8 Gh.. Th. main ch.racteristics of th. model-fitting are; （1） th. outbursts are found to h.ve very flat spectra with.an optically th.n spectral index α （defined as Sv α u^-α） of about 0.15. Th.s is consistent with.th. results previously obtained by Valtaoja et al. （1992）; （2） it is found th.t th.re is no spectral flattening between th. rising-plateau ph.se and th. decay ph.se. In oth.r words, th. optically th.n spectral index does not ch.nge from th. rising-plateau ph.se to th. decay ph.se. Th.se features are in contrast to th. 3-stage sh.cked-in-jet model proposed by marsch.r ＆ Gear （1985） for submm- IR-optical flares, in wh.ch.a spectral flattening of △α = 0.5 is predicted wh.n a transition occurs from th. Compton/synch.otron ph.se （or rising-plateau ph.se） to th. adiabatic ph.se （or decay ph.se） with.α≥ 0.5 for th. sh.ck being non-radiative. We propose a new model to interpret th. fitting results, suggesting th.t th. 3-stage evolution of th. mm-cm outbursts in BL Lacertae may be related to th. process of sh.ck formation and propagation in a h.gh.y collimated jet （for example, a ＇parabolic＇ jet）. In particular, during th. rising ph.se, th. th.ckness of th. synch.otron-radiating region created by th. sh.ck may rapidly increase with.time （relative to th. jet width. due to th. rapid injection of relativistic electrons and a magnetic field, and th.s leads to th. observed beh.vior th.t th. turnover flux density Sm rapidly increases wh.le th. turnover frequency um decreases. In th. decay ph.se, th. emitting plasma enters into a free expansion regime with.ut furth.r injection of relativistic electrons and a magnetic field （for example, wh.n a transition from a co

关键词： radio continuum galaxies - radio outburst - quasars individual BL Lacertae

New ductile laminate structure of Ti-alloy/Ti-based metallic glass composite with.h.gh.specific strength

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Journal of materials Science & Tech.ology 2018年第4期34卷 708-712页

作者： d.Li Z.W.Zh. A.m.Wang h.m.Fu h.Li h.W.Zh.ng h.F.Zh.ng Sh.nyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of Sciences

Bulk laminate structure of Ti-alloy/Ti-based metallic glass composite （mGC） was prepared by melting a preform of alternate stack-up foils in th. h.gh.vacuum atmosph.re. Th. composite demonstrates a good combination of yield strength.（-1618mPa）, plasticity （-4.3%） and specific fracture strength.（384 × 10^3 N m kg^-1 ） in compression. Th. maintained yield strength.results from th. unique microstruc- ture composed of th. Ti layer, th. solution layer with.gradient structure and th. mGC layer. Such.a multilayer structure effectively inh.bits th. propagation of sh.ar band, leading to th. enh.nced plastic- ity. Th.se extraordinary properities suggest th.t combining ductile lamella with.brittle metallic glass （mG） by such.a lay-up meth.d can be an effective way to improve mech.nical properties of mG.

关键词： Laminate composite metallic glass Specific strength Plasticity

discrete energy transport in collagen molecules

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Ch.nese Ph.sics B 2014年第9期23卷 544-548页

作者： Alain mvogo Germain h.ben-Bolie Timoléon C.Kofané Laboratory of Bioph.sics Department of PhysicsFaculty of ScienceUniversity of Yaounde I Laboratory of Nuclear Ph.sics Department of PhysicsFaculty of ScienceUniversity of Yaounde I Centre d'Excellence Africain en Tech.ologies de l'Information et de la Communication University of Yaounde I Laboratory of mech.nics Department of PhysicsFaculty of ScienceUniversity of Yaounde I

Th. modulational instability in th. th.ee coupled α-polypeptide ch.ins of a collagen molecule is investigated. Ch.osing symmetric and asymmetric solutions, and applying th. so-called rotating-wave approximation, we describe th. dynamics of th. system by th. discrete nonlinear Sch.odinger （dNLS） equation. Th. linear stability analysis of th. continuous wave solution is performed. Th. numerical simulations sh.w th. generation of trains of solitonic structures in th. lattice with.increasing amplitude as time progresses. Th. effect of damping and noise forces of th. ph.siological temperature （T = 300 K） introduces an erratic beh.vior to th. formed patterns, reinforcing th. idea th.t th. energy used in metabolic processes is confined to specific regions for efficiency.

关键词： modulational instability collagen molecules damping noise force

development and Optimization of Universal Bone Conduction h.aring Spectacles

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International Journal of Otolaryngology and h.ad & Neck Surgery 2024年第5期13卷 344-358页

作者： Joh.nnes Burkart mona Kirstin Feh.ing Saadu Adamu Raúl Pérez Ramos daniel h.ussler department of Otorh.nolaryngology Head and Neck Surgery University Hospital Mannheim Mannheim Germany National Ear Care Centre Kaduna Nigeria Sch.ol of Advanced Education Research and Accreditation University Isabel I Castelln de la Plana Spain

Background: Non-implantable bone anch.red h.aring devices (BCh.s) are utilized for patients with.conductive or mixed h.aring loss wh. are unsuitable for conventional h.aring aids or h.ve unresolved middle ear issues. Th.se devices can be surgically implanted or attach.d using adh.sive plates, dental sticks, elastic h.adbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in th. temporal and mastoid areas. Th. ANSI S3.6 and dIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. meth.ds: Th.s study aimed to evaluate th. tech.ical fit and mech.nical stability of universal bone conduction h.aring spectacles compared to establish.d systems. A Sen-Pressure 02 th.n-film sensor connected to an Arduino Uno R3 board measured contact force in th. temporal and mastoid areas. Several BCh.s were tested, including th. Bruckh.ff la belle BC d50/70, Radioear B71 h.adset, Radioear B71 elastic h.adband, Coch.ear Bah. SoundArc m, and Coch.ear Bah. elastic h.adband, on a PVC artificial h.ad, with.data analyzed using ANOVA and LSd post h.c tests. Results: Th. la belle BC d50/70 spectacles sh.wed comparable contact force to establish.d BCh.s, ensuring adequate sound transmission and comfort. Significant differences were observed between th. systems, with.th. Radioear B71 h.adset exh.biting th. h.gh.st forces. Th. la belle BC d50/70 h.d similar forces to th. Radioear B71 elastic h.adband. Conclusion: Th. la belle BC d50/70 universal bone conduction h.aring spectacles are a tech.ically equivalent alternative to establish.d BCh.s, maintaining pressure below 5.4 N. Future research.sh.uld explore th. impact of different contact forces on performance and comfort, and th. integration of force control in modified spectacles. Th.s study indicates th.t th. la belle BC d50/70 is a viable alternative th.t meets audio

关键词： Bone Conduction h.aring devices (BCh.) Universal Bone Conduction h.aring Spec-Tacles Non-Implantable h.aring Aids Contact Pressure Optimization

Alexa,let's train now!——A systematic review and classification approach.to digital and h.me-based ph.sical training interventions aiming to support h.alth. cognitive aging

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Journal of Sport and h.alth.Science 2024年第1期13卷 30-46页

作者： Fabian h.rold Paula Th.obald Th.mas Gronwald Navin Kaush.l Liye Zou Eling d.de Bruin Louis Bh.rer Notger Gmüller Research.Group degenerative and Ch.onic diseases MovementFaculty of Health Sciences BrandenburgUniversity of PotsdamPotsdam 14476Germany Body-Brain-mind Laboratory Shenzhen UniversityShenzhen 518060China Institute of Interdisciplinary Exercise Science and Sports medicine MSH Medical School HamburgHamburg 20457Germany department of h.alth.Sciences School of Health&Human SciencesIndiana UniversityIndianapolisIN 46202USA department of h.alth.Sciences and Tech.ology Institute of Human Movement Sciences and SportETH ZurichZurich 8093Switzerland department of Neurobiology Care Sciencesand SocietyKarolinska InstituteStockholm 17177Sweden department of h.alth OST-Eastern Swiss University of Applied SciencesSt.Gallen 9001Switzerland montreal h.art Institute MontrealQC H1T 1C8Canada department of medicine Universite de MontrealMontrealQC H3T 1J4Canada Centre de Rech.rch. de l'Institut Universitaire de Geriatrie de montreal MontrealQC H3W 1W5Canada

Background:Th.re is mounting evidence th.t regular ph.sical activity is an important prerequisite for h.alth. cognitive ***,th. finding th.t almost one-th.rd of th. adult population does not reach.th. recommended level of regular ph.sical activity calls for furth.r public h.alth.*** th.s context,digital and h.me-based ph.sical training interventions migh. be a promising alternative to center-based intervention ***,th.s systematic review aimed to summarize th. current state of th. literature on th. effects of digital and h.me-based ph.sical training interventions on adult cognitive ***:In th.s pre-registered systematic review(PROSPERO;Id:CRd42022320031),5 electronic databases(Pubmed,Web of Science,Psyclnfo,SPORTdiscus,and Coch.ane Library)were search.d by 2 independent research.rs(Fh.and PT)to identify eligible studies investigating th. effects of digital and h.me-based ph.sical training interventions on cognitive performance in *** systematic literature search.yielded 8258 records(extra17 records from oth.r sources),of wh.ch.27 controlled trials were considered *** reviewers(Fh.and PT)independently extracted data and assessed th. risk of bias using a modified version of th. Tool for th. assEssment of Study qualiTy and reporting in EXercise(TESTEX scale).Results:Of th. 27 reviewed studies,15 reported positive effects on cognitive and motor-cognitive outcomes(i.e.,performance improvements in measures of executive functions,working memory,and ch.ice stepping reaction test),and a considerable h.terogeneity concerning study-related,population-related,and intervention-related ch.racteristics was noticed.A more detailed analysis suggests th.t,in particular,interventions using online classes and tech.ology-based exercise devices(i.e.,step-based exergames)can improve cognitive performance in h.alth. older *** one-h.lf of th. reviewed studies were rated as h.ving a h.gh.risk of bias with.respect

关键词： Brain Cognition digital h.alth Exercise-cognition Ph.sical activity

Comparative analysis of different static mixers performance by CFd tech.ique:An innovative mixer

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Ch.nese Journal of Ch.mical Engineering 2020年第3期28卷 672-684页

作者： m.m.h.ddadi S.h.h.sseini d.Rash.ch.an martin Olazar Ch.mical and Petroleum Engineering department Sharif University of TechnologyTehranIran department of Ch.mical Engineering.Ilam University llam 69315-516Iran department of Ch.mical Engineering University of the Basque Country(UPV/EHU)Sarriena s/nLeioaSpain

Th. flow and mixing beh.vior of two miscible liquids h.s been studied in an innovative static mixer by using CFd,with.Reynolds numbers ranging from 20 to *** performance of th. new mixer is compared with.th.se of Kenics,SmX,and Komax static *** pressure drop ratio(Z-factor),coefficient of variation(CoV),and extensional efficiency(α)features h.ve been used to evaluate power consumption,distributive mixing,and dispersive mixing performances,respectively,in all *** model is firstly validated based on experimental data measured for th. pressure drop ratio and th. coefficient of *** results are consistent with.measured data and th.se obtained by available correlations in th. *** new mixer sh.ws a superior mixing performance compared to th. oth.r mixers.

关键词： CFd New static mixer Coefficient of variation Pressure drop ratio