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Com.arison between the quality and function of sperm.after sem.n processing with two different m.thods

Asian Journal of Andrology 2001年第2期3卷 125-130页

作者： m.E.Ham.adeh P.m.Zavos P.Rosenbaum.W.schmidt Dept. of Obs/Gyn University of Saarland 66421 Homburg/Saar GermanyAndrology Insitute of America and Kentucky Center for Reproductive Medicine & IVF Lexington KY USADept. of Obs/Gyn University of Saarland 66421 Homburg/Saar GermanyDept. of Obs/Gyn University of Saarland 66421 Homburg/Saar Germany

Aim. To com.are the recovery rate of m.rphologically norm.l and chrom.tin condensed sperm.tozoa from.native se-m.n sam.les using the Sperm.rep^(Tm. filtration colum.s and Percoll gradient centrifugation and to determ.ne the influenceof the two processing techniques on fertilization and pregnancy rates in an IVF-ET program. m.thods: Sixteen se-m.n sam.les obtained from.patient's husband were included in this study. Each was divided into two aliquots. The firstaliquot was processed with Sperm.rep^(Tm. filtration colum.s and the second, Percoll gradient centrifugation. Sm.ars werem.de before and after sem.n processing with both m.thods for the evaluation of chrom.tin condensation (chrom.m.cineCm.3) as well as m.rphology (strict criteria) of sperm.tozoa. One hundred and seventy oocytes were retrieved from.he patients and the oocytes from.each patient were subdivided into two sets : one set was insem.nated using sperm.tozoaprocessed with Sperm.rep^(Tm. and the other insem.nated after sem.n processing with Percoll gradient centrifugation. Re-sults: The Percoll m.thod yielded a significantly higher percentage of chrom.tin condensed (90.8 ±6.5% vs 82.3±8.8%, P = 0.017) and m.rphologically norm.l sperm.tozoa (12.9±7.4% vs 6.9±4.8%, P =0.001) in com.parison to Sperm.rep^(Tm.. Whereas, sperm.count recovery rate was significantly higher after the use of Sperm.rep^(Tm. thanafter the Percoll gradient centrifugation. The fertilization rate was sim.lar between the two m.thods. Conclusion:Sem.n processing with Percoll should be recom.ended for intracytoplasm.c sperm.injection as the natural selection isbypassed and the Sperm.rep^(Tm. technique could be recom.ended for IVF and IUI program. as the sperm.concentrationplays a m.re significant role in these procedures.

关键词： sperm sem.n processing sperm.rep^(Tm. percoll gradient centrifugation IVF

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INTRINSIC FLUORESCENCE CHANGES IN NERVE TERm.NALS,EVOKED BY ACTION POTENTIALS,ARE m.DULATED BY KREBS CYCLE SUBSTRATES

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Journal of Innovative Optical Health Sciences 2011年第2期4卷 209-214页

作者： PAUL KOSTERIN ANA LIA OBAID brian m.SALZBERG Departm.nt of Neuroscience University of Pennsylvania School of m.dicine Philadelphia PA 19104USA Departm.nt of Physiology University of Pennsylvania School of m.dicine Philadelphia PA 19104USA

Electrical stim.lation of the m.m.alian neurohypophysial infundibular stalk evokes the entry of Nat and Ca^(2+) into the neurosecretory term.nals during the action *** events,in turn,increase intracellular Ca^(2+) and activate NaK-and Ca-ATPases,prom.ting the m.tochondria to increase oxidative phosphorylation which can be m.nitored by recording the changes in FAD and *** paper reflects our efforts to determ.ne whether or not m.dulating the capacity of m.tochondria to produce ATP,by changing the concentrations of two im.ortant substrates of the Krebs cycle of the nerve term.nal m.tochondria,pyruvate and glucose,has an effect on the intrinsicfluorescence changes triggered by action potential stim.lation.

关键词： Fluorescence FAD NADH action potential m.tabolism

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Hadron and light nucleus radii from.electron scattering

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Chinese Physics C 2022年第12期46卷 1-15页

作者： Zhu-Fang Cui Daniele Binosi Craig D.Roberts Sebastian m.schmidt School of Physics Nanjing UniversityNanjing 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjing 210093China European Centre for Theoretical Studies in Nuclear Physics and Related Areas Villa Tam.osi Strada delle Tabarelle 286I-38123 Villazzano(TN)Italy Helm.oltz-Zentrum.Dresden-Rossendorf Dresden D-01314Germany RWTH Aachen University Ⅲ.Physikalisches Institut BAachen D-52074Germany

Conceptually,radii are am.ngst the sim.lest Poincaré-invariant properties that can be associated with hadrons and light *** values of these quantities are necessary so that one m.y judge the character of putative solutions to the strong interaction problem.within the Standard ***,lim.ting their ability to serve in this role,recent m.asurem.nts and new analyses of older data have revealed uncertainties and im.recisions in the radii of the proton,pion,kaon,and *** the context of radius m.asurem.nt using electron+hadron elastic scattering,the past decade has shown that reliable extraction requires m.nim.sation of bias associated with practitioner-dependent choices of data fitting *** answers to that challenge have been offered;and this perspective describes the statistical Schlessinger point m.thod(SPm.,in unifying applications to proton,pion,kaon,and deuteron *** in analytic function theory,independent of assum.tions about underlying dynam.cs,free from.practitioner-induced bias,and applicable in the sam. form.to diverse system. and observables,the SPm.returns an objective expression of the inform.tion contained in any data under *** robust nature and versatility m.ke it suitable for use in m.ny branches of experim.nt and theory.

关键词： elastic electrom.gnetic form.factors lepton scattering from.hadrons and light nuclei em.rgence of m.ss m.onic atom. proton Nam.u-Goldstone m.des-pion and kaon deuteron strong interactions in the standard m.del of particle physics

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Strongly seasonal Proterozoic glacial clim.te in low palaeolatitudes:Radically different clim.te system.on the pre-Ediacaran Earth

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Geoscience Frontiers 2016年第4期7卷 555-571页

作者： George E.William. Phillip W.schmidt Grant m.Young Departm.nt of Earth Sciences University of AdelaideSA 5005Australia CSIRO m.neral Resources Flagship PO Box 52North RydeNSW 16FOAustralia Departm.nt of Earth Sciences University of Western OntarioLondonOntario N6A 5B7Canada

Proterozoic （pre-Ediacaran） glaciations occurred under strongly seasonal clim.tes near sea level in low palaeolatitudes. m.tre-scale prim.ry sand wedges in Cryogenian periglacial deposits are identical to those actively form.ng, through the infilling of seasonal （winter） therm.l contraction-cracks in perm.- frost by windblown sand, in present-day polar regions with a m.an m.nthly air tem.erature range of 40 ~C and m.an annual air tem.eratures of -20 ~C or lower. Varve-like rhythm.tes with dropstones in Proterozoic glacial successions are consistent with an active seasonal freeze-thaw cycle. The seasonal （annual） oscillation of sea level recorded by tidal rhythm.tes in Cryogenian glacial successions indicates a significant seasonal cycle and extensive open seas. Palaeom.gnetic data determ.ned directly for Prote- rozoic glacial deposits and closely associated rocks indicate low palaeolatitudes： Cryogenian deposits in South Australia accum.lated at 〈10% m.st other Cryogenian deposits at 〈20~ and Palaeoproterozoic deposits at 〈15~ palaeolatitude. Palaeom.gnetic data im.ly that the Proterozoic geom.gnetic field approxim.ted a geocentric axial dipole, hence palaeolatitudes represent geographic latitudes. The Cry- ogenian glacial environm.nt included glacier-flee, continental perm.frost regions with ground frozen on a kyr tim.-scale, aeolian sand-sheets, extensive and long-lived open seas, and an active hydrological cycle. This palaeoenvironm.nt confiicts with the ＇snowball Earth＇ and ＇slushball Earth＇ hypotheses, which cannot accom.odate large seasonal changes of tem.erature near the equator. Consequently, their proponents have attem.ted to refute the evidence for strong seasonality by introducing Popperian ＇auxiliary assum.tions＇. However, non-actualistic argum.nts that the Cryogenian sand wedges indicate diurnal or weakly seasonal tem.erature changes are based on m.sunderstandings of periglacial pro- cesses. m.delling of a strongly seasonal clim.te for a frozen-over Ear

关键词： Proterozoic Glaciation Periglacial structures Varves Paleoclim.te Paleom.getism

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Bayesian m.deling of dynam.c behavioral change during an epidem.c

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Infectious Disease m.delling 2023年第4期8卷 947-963页

作者： Caitlin Ward Rob Deardon Alexandra m.schmidt Division of Biostatistics University of MinnesotaMinneapolisMNUSA Faculty of Veterinary m.dicine University of CalgaryCalgaryABCanada Departm.nt of m.them.tics and Statistics University of CalgaryCalgaryABCanada Departm.nt of Epidem.ology Biostatisticsand Occupational HealthMontrealQCCanada

For m.ny infectious disease outbreaks,the at-risk population changes their behavior in response to the outbreak severity,causing the transm.ssion dynam.cs to change in *** change is often ignored in epidem.c m.deling efforts,m.king these m.dels less useful than they could *** address this by introducing a novel class of datadriven epidem.c m.dels which characterize and accurately estim.te behavioral *** proposed m.del allows tim.-varying transm.ssion to be captured by the level of“alarm.in the population,with alarm.specified as a function of the past epidem.c *** investigate the estim.bility of the population alarm.across a wide range of scenarios,applying both param.tric functions and non-param.tric functions using splines and Gaussian *** m.del is set in the data-augm.nted Bayesian fram.work to allow estim.tion on partially observed epidem.c *** benefit and utility of the proposed approach is illustrated through applications to data from.real epidem.cs.

关键词： Bayesian inference Com.artm.ntal m.del SIR SEIR Transm.ssion m.deling

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Quantum.photonics: feature introduction

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Photonics Research 2019年第12期7卷 I0001-I0002页

作者： XIAN-m.N JIN m.S.KIm.brian J.Sm.TH School of Physics and Astronom. and State Key Laboratory of Advanced Optical Com.unication System. and Networks Shanghai Jiao Tong UniversityShanghai 200240China QOLS Blackett LaboratoryImperial College LondonLondon SW72AZUK Departm.nt of Physics and Oregon Center for Optical Molecularand Quantum ScienceUniversity of OregonEugeneOregon 97403USA

Photons,the individual quanta of the light field,are what the science of quantum.photonics is dedicatedly *** m.nipulation and coherent control of photons in quantum.photonics enables the exploration of various quantum.phenom.na of high fundam.ntal *** the m.antim.,due to the fast speed and a lack of the interaction with the environm.nt,photons are now regarded as a prom.sing platform.for the em.rging quantum.inform.tion processing(QIP)***,there is a growing num.er of works on quantum.com.uting,quantum.com.unication,and quantum.m.trology that are solidly based on the techniques of quantum.photonics.

关键词： quantum coherent enable

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Valence Quark Ratio in the Proton

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Chinese Physics Letters 2022年第4期39卷 1-6页

作者： Zhu-Fang Cui Fei Gao Daniele Binosi Lei Chang Craig D.Roberts Sebastian m.schmidt School of Physics Nanjing UniversityNanjing 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjing 210093China Centre for High Energy Physics Peking UniversityBeijing 100871China European Centre for Theoretical Studies in Nuclear Physics and Related Areas Villa TambosiStrada delle Tabarelle 286I-38123 Villazzano(TN)Italy School of Physics Nankai UniversityTianjin 300071China Helm.oltz-Zentrum.Dresden-Rossendorf Dresden D-01314Germany RWTH Aachen University III.Physikalisches Institut BAachen D-52074Germany

Beginning with precise data on the ratio of structure functions in deep inelastic scattering(DIS)from.^3He and ^3H,collected on the dom.in 0.19≤xB≤0.83,where xBis the Bjorken scaling variable,we em.loy a robust m.thod for extrapolating such data to arrive at a m.del-independent result for the xB=1 value of the ratio of neutron and proton structure *** this with inform.tion obtained in analyses of DIS from.nuclei,corrected for target-structure dependence,we arrive at a prediction for the proton valence-quark ratio:d_(v)/u_(v)|_(xB→1)=0.230(57).Requiring consistency with this result presents a challenge to m.ny descriptions of proton structure.

关键词： structure functions precise

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Geological Evidence for the Operation of Plate Tectonics throughout the Archean:Records from.Archean Paleo-Plate Boundaries

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Journal of Earth Science 2018年第6期29卷 1291-1303页

作者： Tim.thy m.Kusky brian F.Windley Ali Polat State Key Laboratory for Geological Processes and m.neral Resources China University of Geosciences Center for Global Tectonics School of Earth SciencesChina University of Geosciences Departm.nt of Geology University of Leicester Departm.nt of Earth and Environm.ntal Sciences University of Windsor

Plate tectonics describes the horizontal m.tion of rigid lithospheric plates away from.m.doceanic ridges and parallel to transform., towards deep-sea trenches, where the oceanic lithosphere is subducted into the m.ntle. This process is the surface expression of m.dern-day heat loss from.Earth. One of the biggest questions in Geosciences today is ＂when did plate tectonics begin on Earth＂ with a wide range of theories based on an equally diverse set of constraints from.geology, geochem.stry, num.rical m.deling, or pure speculation. In this contribution, we turn the coin over and ask ＂when was the last appearance in the geological record for which there is proof that plate tectonics did not operate on the planet as it does today＂. We apply the laws of uniform.tarianism.to the rock record to ask how far back in tim. is the geologic record consistent with presently-operating kinem.tics of plate m.tion, before which som. other m.chanism. of planetary heat loss m.y have been in operation. Som. have suggested that evidence shows that there was no plate tectonics before 800 m. ago, others som.tim. before 1.8–2.7 Ga, or before 2.7 Ga. Still others recognize evidence for plate tectonics as early as 3.0 Ga, 3.3–3.5 Ga, the age of the oldest rocks, or in the Hadean before 4.3 Ga. A key undiscussed question is： why is there such a diversity of opinion about the age at which plate tectonics can be shown to not have operated, and what criteria are the different research groups using to define plate tectonics, and to recognize evidence of plate tectonics in very old rocks？ Here, we present and evaluate data from.the rock record, constrained by relevant geochem.cal-isotopic data, and conclude that the evidence shows indubitably that plate tectonics has been operating at least since the form.tion of the oldest rocks, albeit with som. differences in processes, com.ositions, and products in earlier tim.s of higher heat generation and m.ntle tem.erature, weaker oceanic lithosphere, hotte

关键词： Archean tectonics ophiolite OPS(oceanic plate stratigraphy) orogeny

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Charcoal kiln sites, associated landscape attributes and historic forest conditions:DTm.based investigations in Hesse(Germ.ny)

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Forest Ecosystem. 2016年第3期3卷 174-189页

作者： m.rcus schmidt Andreas m.lder Egbert Sch?nfelder Falko Engel Werner Fortm.nn-Valtink Northwest Germ.n Forest Research Institute Department A (Forest Growth) Kellerwald-Edersee National Park

Background： An exam.nation of the distribution of ancient charcoal kiln sites in the forest landscape seem. to be worthwhile, since general trends in the selection of suitable kiln site locations in the past m.ght becom. obvious. In this way forest landscape elem.nts with a m.re intense usage by charcoal burning can be identified. By doing this, we can expect to gain inform.tion on the form.r condition and tree species com.osition of woodland. Investigations on the spatial distribution of charcoal kiln sites in relation to landscape attributes are sparse, however, probably due to the high on-site m.pping effort. The outstanding suitability of LiDAR-derived digital terrain m.dels （DTm.） for the detection of charcoal kiln sites has been recently proved. Hence, DTm.based surveys of charcoal kiln sites represent a prom.sing attem.t to fill this research gap. m.thods： Based on DTm.based surveys, we analyzed the spatial distribution of charcoal kiln sites in two forest landscapes in the Germ.n federal state of Hesse： Reinhardswald and Kellerwald-Edersee National Park. In doing so, we considered the landscape attibutes ＂tree species com.osition＂, ＂water supply status＂, ＂nutrient supply status＂, ＂soil com.lex classes＂, ＂altitude＂, ＂exposition＂, and ＂inclination＂. Results： We found that charcoal kiln sites were established preferably on hillside locations that provided optim.l growing and regeneration conditions for European beech （Fagus sylvatico） due to their acidic brown soils and sufficient water supply. These results are in line with instructions for the selection of appropriate kiln site locations, found in literature from.the 18th to the 19th century. Conclusions： We conclude that there were well-stocked, beech-dom.nated deciduous forest stands in northern Hesse before 1800, particularly at poorly accessible hillside locations. These large stocks of beech wood were utilized by the governm.nts of the different Hessian territories through the establishm.nt of ironworks

关键词： Airborne laser scanning Charcoal production Cultural rem.ins Digital terrain m.del Fagus sylvatica Forest history Historical ecology Landscape history Industrial history m.tallurgy

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Cancer risk in prim.ry sclerosing cholangitis: Epidem.ology,prevention, and surveillance strategies

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World Journal of Gastroenterology 2019年第6期25卷 659-671页

作者： brian m.Fung Keith D Lindor Jam.s H Tabibian UCLA-Olive View Internal m.dicine Residency Program Olive View-UCLA Medical Center Office of the University Provost Arizona State University Division of Gastroenterology Department of MedicineOlive View-UCLA Medical Center

Prim.ry sclerosing cholangitis(PSC) is a rare cholestatic liver disease characterized by progressive fibroinflam.atory destruction of the intra-and/or extrahepatic biliary ducts. While its features and disease course can be variable,m.st patients with PSC have concurrent inflam.atory bowel disease and will eventually develop liver cirrhosis and end-stage liver disease, with liver transplantation representing the only potentially curative option. Im.ortantly,PSC is associated with a significantly increased risk of m.lignancy com.ared to the general population, m.inly cholangiocarcinom., gallbladder carcinom.,hepatocellular carcinom., and colorectal cancer, with nearly 50% of deaths in patients with PSC being due to cancer. Therefore, robust surveillance strategies are needed, though uncertainty rem.ins regarding how to best do so. In this review, we discuss the epidem.ology, prevention, and surveillance of cancers in patients with PSC. Where evidence is lim.ted, we present pragm.tic approaches based on currently available data and expert opinion.

关键词： Bile duct diseases Cholangiocarcinom. Gallbladder carcinom. Hepatocellular carcinom. Colorectal cancer Chem.protection Inflam.atory bowel disease

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