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Asian Journal of Andrology 2001年第2期3卷 109-114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 S 10 2TN UK

Aim: To evaluate the effects of 1,3-dinitrobenznene (mdNB) on sperm motility of hamster and to correlate the re-sults with the fertility. Methods: Adult male hamsters were gavaged with one of the 3 dose regimes of mdNB(1.5 mg daily for 4 weeks ,1.5 mg one day a week for 4 weeks and 1.0 mg 3 days a week for 4 weeks). computerassisted semen analysis (cASA) was used to analyse the sperm motility parameters, curvilinear velocity (Vcl) andstraight line velocity (VSl) of sperm in distal corpus epididymides and distal cauda epididymides. In vitro fertilisationwas carried out only for 1.5 mg mdNB daily group to determine the sperm fertilising capacity. Results: There wasa significant reduction in sperm velocity parameters at weeks 3 and 4 after treatment, which was correlated with a de-cline in sperm fertility. conclusion; Sperm velocity parameters may be used to determine the effect of a toxic insulton the sperm function.

关键词： mdNB sperm motility cASA sperm fertility

Effects of acut and chronic doses of methoxy acetic acid on hamster 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 the effects of acute and chronic doses of methoxy acetic acid (MAA) on in vitro fertilisation byhamster sperm and to correlate the data with the testicular damage. Methods: Adult male hamsters were gavagedwith 3 single doses (0, 80, 160 and 650 mg/kg) and 3 chronic doses (0, 8, 32 and 64 mg/kg daily for 5 weeks) ofMAA in distilled water. After treatment hamsters were killed at weekly intervals and spermatozoa recovered from thedistal cauda epididymides were used to assess the fertilising capacity in vitro. The testes were processed for histologicalexamination. Results; Acute doses showed a significant reduction in sperm fertilising ability from week 3 and 4 af-ter treatment and with the chronic doses, the effects were more extensive and persistent. The results were in correpon-dence with the testicular damages observed. conclusion: It is evident that both acute and chronic doses of MAAcan impair the sperm function by damaging one or more cell populations in the testis.(Asian J Androl 2001 Sep; 3: 209- 216)

关键词： methoxy acetic acid fertilisation in vitro testis spermatozoa fertility

High-Entropy ceramics ReVO4 and Microwave dielectric Properties

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Kuei Suan Jen Hsueh Pao/Journal of the chinese ceramic Society 2024年第9期52卷 2907-2914页

作者： chen d. Mo c. Nong l. cui H. Wang Z. liu l. li c. Guangxi University Key laboratory of Non-Ferrous Metal Oxide Electronic Functional Materials and devices College of Material Science and Engineering Guilin University of Technology Guangxi Guilin 541004 China Guangxi Key laboratory of Embedded Technology and Intelligent System Guilin University of Technology Guilin 541004 China

Introduction Microwave dielectric ceramics are widely used in microwave frequency (i.e., 300 MHz–300 GHz) circuits as communication electronic components such as resonators, filters, and antennas. The dielectric permittivity (εr), quality factor (Q×f) and the temperature coefficient of resonant frequency (τf) are the main performance index to measure the quality of microwave dielectric ceramics. However, there is a constraint relationship between the performance parameters. In general, the giant εr may cause a large dielectric loss and a low Q×f, and the volatility of εr originates an enormous τf value. Therefore, materials with superior intrinsic microwave dielectric properties are rare. The existing methods of controlling microwave dielectric properties mainly include ion substitution, composite control, laminated control and non-stoichiometric ratio control. These methods often require sacrificing one parameter to satisfy other parameters. High-entropy strategy is a novel regulation method used in inorganic materials. High-entropy ceramics refer to a ceramic system with a configuration entropy (Sc) of 1.5R. The high-entropy effect, sluggish diffusion effect, lattice distortion effect and synergy in components (i.e., cocktail effect) are four special effects of high-entropy ceramics. The high-entropy strategy shows a great potential in dielectric ceramics due to these unique effects. In this paper, high-entropy strategy was used to design rare-earth vanadate ceramics. The impact of high-entropy structure on the microwave dielectric properties was investigated. Methods High-entropy ceramics of ReVO4 were synthesized by a solid-phase method with high-purity rare earth oxides (Re2O3 with a purity of > 99.9%) and V2O5. The ceramics with different chemical formulas (la0.2ce0.2Nd0.2Sm0.2Eu0.2)VO4, (la0.2ce0.2Nd0.2Sm0.2 Gd0.2)VO4, and (la0.2ce0.2Nd0.2Sm0.2Y0.2)VO4, were denoted as Eu-5RVO, Gd-5RVO, and Y-5RVO, respectively. The raw materials were weighed according to a s

关键词： dielectric properties high-entropy ceramic microwave frequency vanadate zircon structure

A multi-shot target wheel assembly for high-repetition-rate, laser-driven proton acceleration

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High Power laser Science and Engineering 2024年第2期12卷 87-94页

作者： J.Penas A.Bembibre d.cortina-Gil l.Martin A.Reija c.Ruiz M.Seimetz A.Alejo J.Benlliure Instituto Galego de Fisica de Altas Enerxias Universidade de Santiago de CompostelaSantiago de CompostelaSpain laboratorio laser de Aceleracion y Aplicaciones RIAIDTUniversidade de Santiago de CompostelaSantiago de CompostelaSpain Instituto Universitario de Física Fundamental y Matematicas y dpto.de didactica de la Matematica y de las ciencias Experimentales Universidad de SalamancaSalamancaSpain Instituto de Instrumentación para Imagen Molecular(I3M) CSIC-Universitat Politecnica de ValenciaValenciaSpain

A multi-shot target assembly and automatic alignment procedure for laser–plasma proton acceleration at high repetition rate are *** assembly is based on a multi-target rotating wheel capable of hosting more than 5000 targets,mounted on a 3d motorized stage to allow rapid replenishment and alignment of the target material between laser *** automatic alignment procedure consists of a detailed mapping of the impact positions at the target surface prior to the irradiation that ensures stable operation of the target,which alongside the purpose-built design of the target wheel,enables operation at rates up to 10 *** and continuous laser-driven proton acceleration at 10 Hz is demonstrated,with observed cut-off energy stability about 15%.

关键词： high repetition rate laser-plasma acceleration multi-shot operation proton source target assembly

Experimental measurements of gamma-photon production and estimation of electron/positron production on the PETAl laser facility

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Matter and Radiation at Extremes 2024年第5期9卷 32-47页

作者： F.Brun l.Ribotte G.Boutoux X.davoine P.E.Masson-laborde Y.Sentoku N.Iwata N.Blanchot d.Batani I.lantuéjoul l.lecherbourg B.Rosse c.Rousseaux B.Vauzour d.Raffestin E.d’Humières X.Ribeyre centre lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance cEA DAMCESTAF-33116 Le BarpFrance cEA DAMDIFF-91297 ArpajonFrance cEA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity PETawatt Aquitaine laser(PETAl)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SESAME(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and l-shells were clearly detected by a photon spectrometer called SPEcTIX(Spectromètre Petalàcristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by cRAcc-X(cassette de RAdiographie centre chambre-rayonnement X),a bremsstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte carlo simulations was *** simulations model the preplasma generated at the front of the target by the PETAl laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enabled reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process. positron hypothesis

comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek J.dittrich M.Knapek F.lukáˇc d.Koutný J.Jaroš R.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SlM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SlM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SlM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M Nacl solution was superior to the SlM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SlM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength corrosion resistance

Extracellular vesicles-coupled miRNAs from oviduct and uterus modulate signaling pathways related to lipid metabolism and bovine early embryo development

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1528-1549页

作者： Rosane Mazzarella Karina canon‑Beltran Yulia N.cajas Meriem Hamdi Encina M.Gonzalez Juliano c.da Silveira claudia l.V.leal d.Rizos department of Animal Reproduction INIA-CSICMadridSpain department of Biochemistry and Molecular Biology Veterinary FacultyComplutense University of Madrid(UCM)MadridSpain department Agrarian Production Technical University of MadridUPMMadridSpain departamento de ciencias Biologicas Universidad Tecnica Particular de LojaUTPLLojaEcuador department of Anatomy and Embryology FV-UCMMadridSpain department of Veterinary Medicine FZEA-USPPirassunungaBrazil

Background Extracellular vesicles(EVs) present in oviductal(OF) and uterine fluid(UF) have been shown to enhance bovine embryo quality during in vitro culture by reducing lipid contents and modulating lipid metabolism-related genes(lMGs), while also influencing cell proliferation, suggesting their involvement on the regulation of different biological pathways. The regulation of signaling pathways related to cell differentiation, proliferation, and metabo-lism is crucial for early embryo development and can determine the success or failure of the pregnancy. Bioactive molecules within EVs in maternal reproductive fluids, such as micro RNAs(miRNAs), may contribute to this regulatory process as they modulate gene expression through post-transcriptional *** This study evaluated miRNA cargo in OF-EVs from the early luteal phase and UF-EVs from the mid-luteal phase, coinciding with embryo transit within oviduct and uterus in vivo, and its possible influence on lMGs and sign-aling pathways crucial for early embryo development. A total of 333 miRNAs were detected, with 11 exclusive to OF, 59 to UF, and 263 were common between both groups. From the 20 differentially expressed miRNAs, 19 up-regulated in UF-EVs(bta-miR-134, bta-miR-151-3p, bta-miR-155, bta-miR-188, bta-miR-181b, bta-miR-181d, bta-miR-224, bta-miR-23b-3p, bta-miR-24-3p, bta-miR-27a-3p, bta-miR-29a, bta-miR-324, bta-miR-326, bta-miR-345-3p, bta-miR-410, bta-miR-652, bta-miR-677, bta-miR-873 and bta-miR-708) and one(bta-miR-148b) in OF-EVs. These miRNAs were predicted to modulate several pathways such as Wnt, Hippo, MAPK, and lipid metabolism and degradation. differ-ences in miRNAs found in OF-EVs from the early luteal phase and UF-EVs from mid-luteal phase may reflect differ-ent environments to meet the changing needs of the embryo. Additionally, miRNAs may be involved, particularly in the uterus, in the regulation of embryo lipid metabolism, immune system, and *** Our study su

关键词： Embryo-maternal interaction Epigenetic Exosomes Mammalian Preimplantation Reproductive fluids

Superior antibody and membrane protein‑specific T‑cell responses to coronaVac by intradermal versus intramuscular routes in adolescents

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World Journal of Pediatrics 2024年第4期20卷 353-370页

作者： Jaime S.Rosa duque Samuel M.S.cheng carolyn A.cohen daniel leung Xiwei Wang Xiaofeng Mu Yuet chung Tsun Ming lau Manni Wang Wenyue Zhang Yanmei Zhang Howard H.W.Wong leo c.H.Tsang Sara chaothai Tsz chun Kwan John K.c.li Karl c.K.chan leo l.H.luk Jenson c.H.Ho Wing Yan li Amos M.T.lee Jennifer H.Y.lam Sau Man chan Wilfred H.S.Wong Issan Y.S.Tam Masashi Mori Sophie A.Valkenburg Malik peiris Wenwei Tu Yu lung lau department of Paediatrics and Adolescent Medicine The University of Hong KongHong KongChina School of Public Health The University of Hong KongHong KongChina HKU‑Pasteur Research Pole School of Public HealthThe University of Hong KongHong KongChina Research Institute for Bioresources and Biotechnology Ishikawa Prefectural UniversityNonoichiJapan department of Microbiology and Immunology Peter Doherty Institute for Infectionand ImmunityUniversity of MelbourneMelbourneVICAustralia center for Immunology and Infection c2i Hong KongChina

Background Optimising the immunogenicity of cOVId-19 vaccines to improve their protection against disease is *** dosing by intradermal(Id)administration has been shown to be equally immunogenic as intramuscular(IM)administration for several vaccines,but the immunogenicity of Id inactivated whole severe acute respiratory syndrome coronavirus 2(SARS-coV-2)at the full dose is *** study(NcT04800133)investigated the superiority of antibody and T-cell responses of full-dose coronaVac by Id over IM administration in *** Participants aged 11–17 years received two doses of IM or Id vaccine,followed by the 3rd dose 13–42 days *** and cellular immunogenicity outcomes were measured post-dose 2(IM-cc versus Id-cc)and post-dose 3(IMccc versus Id-ccc).doses 2 and 3 were administered to 173 and 104 adolescents,*** Spike protein(S)immunoglobulin G(IgG),S-receptor-binding domain(RBd)IgG,S IgG Fcγreceptor IIIa(FcγRIIIa)-binding,SNM[sum of individual(S),nucleocapsid protein(N),and membrane protein(M)peptide pool]-specific interleukin-2(Il-2)+cd4^(+),SNM-specific Il-2^(+)cd8^(+),S-specific Il-2^(+)cd8^(+),N-specific Il-2^(+)cd4^(+),N-specific Il-2^(+)cd8^(+)and M-specific Il-2^(+)cd4^(+)responses fulfilled the superior and non-inferior criteria for Id-cc compared to IM-cc,whereas IgG avidity was *** Id-ccc,S-RBd IgG,surrogate virus neutralisation test,90%plaque reduction neutralisation titre(PRNT90),PRNT50,S IgG avidity,S IgG FcγRIIIa-binding,M-specific Il-2^(+)cd4^(+),interferon-γ+cd8^(+)and Il-2^(+)cd8^(+)responses were superior and non-inferior to *** estimated vaccine efficacies were 49%,52%,66%and 79%for IM-cc,Id-cc,IM-ccc and Id-ccc,*** Id groups reported more local,mild adverse *** This is the first study to demonstrate superior antibody and M-specific T-cell responses by Id inactivated SARScoV-2 vaccination and serves as the basis for future research to improve the

关键词： coronaVac coronavirus disease 2019 Immunity Intradermal Vaccine

Radioisotope production using lasers:From basic science to applications

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Matter and Radiation at Extremes 2024年第3期9卷 31-44页

作者： M.R.d.Rodrigues A.Bonasera M.Scisciò J.A.Pérez-Hernández M.Ehret F.Filippi P.l.Andreoli M.Huault H.larreur d.Singappuli d.Molloy d.Raffestin M.Alonzo G.G.Rapisarda d.lattuada G.l.Guardo c.Verona Fe.consoli G.Petringa A.McNamee M.la cognata S.Palmerini T.carriere M.cipriani G.di Giorgio G.cristofari R.de Angelis G.A.P.cirrone d.Margarone l.Giuffrida d.Batani P.Nicolai K.Batani R.lera l.Volpe d.Giulietti S.Agarwal M.Krupka S.Singh Fa.consoli cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly centro de láseres Pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain centre lasers Intenses et Applications(cElIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings Pty FreshwaterNew South WalesAustralia School of Mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom dipartimento di Fisica e Astronomia“E.Majorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly dipartimento di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly ElI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of czech Academy of Sciences PragueCzech Republic Institute of Plasma Physics of czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)cu,^(63)Zn,^(18)F,and^(11)c,which are currently used in positron emission tomography and other *** the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy *** experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

Single atom cu-N-c catalysts for the electro-reduction of cO_(2) to cO assessed by rotating ring-disc electrode

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Journal of Energy chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez M.Gutiérrez-Roa c.Giménez-Rubio d.Ríos-Ruiz P.Arévalo-cid M.V.Martínez-Huerta A.Zitolo M.J.lázaro d.Sebastián Instituto de carboquímica(cSIc) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de catálisis y Petroleoquímica(cSIc) Marie Curie 228049 MadridSpain Synchrotron SOlEIl L’Orme des MerisiersDépartementale 12891190France

The electrochemical cO_(2) reduction reaction(cO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(cu-N-c) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient cO_(2)RR. The electrocatalytic performance of cu-N-c materials is assessed by a rotating ring-disc electrode(RRdE), technique still rarely explored for cO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized cu-Nc catalysts are found to be active and highly cO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHcO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing cu-N_(4) moieties exhibits a cO_(2)-to-cO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/cO ratio of 1.8. These results demonstrate that RRdE configuration can be used as a feasible approach for identifying electrolysis products from cO_(2)RR.

关键词： cu-N-c carbon xerogel Rotating ring disc electrode carbon dioxide reduction reaction carbon monoxide