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Another piece of the meios.s.puzzle

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As.an Journal of Andrology 2017年第1期19卷 3-4页

作者： Paul s.cooke Manjunatha K Nanjappa Department of Phys.ological s.iences College ofVeterinary Medicine University of Florida GainesvilleFL 32608 USA.

Meios.s. the proces. by which the ovary and tes.is.produce haploid gametes.from initially diploid cells. is.es.ential for s.xual reproduction in mammals. This.proces., initially des.ribed in the late 19th and early 20th century us.ng model organis.s.s.ch as.s.a urchins. worms.and fruit flies. continues.to attract extens.ve interes. from reproductive biologis.s.due to its.centrality in gametogenes.s.

关键词： tes.is produce haploid

How to make a human germ cell

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As.an Journal of Andrology 2015年第3期17卷 441-442页

作者： Paul s.cooke Manjunatha K Nanjappa Department of Phys.ological s.iences College ofVeterinary Medicine University of Florida GainesvilleFL 32608 USA

How the primordial germ cell （PGC） lineage, which eventually gives.ris. to s.ermatozoa in males.and oocytes.in females. is.es.ablis.ed in the developing mammalian embryo has.been a critical topic in both developmental and reproductive biology for many years. There have been s.gnificant breakthroughs.over the pas. two decades.in es.ablis.ing both the s.urce of PGCs.and the factors.that regulate the s.ecification of this.lineage in mice,~ but our unders.anding of the factors.that control PGC development in the human is.rudimentary. The s.Y-related HMG-box （s.X） family of trans.ription factors.cons.s.s.of 20 genes.in humans.and mice that are involved in the maintenance of pluripotency, male s.xual development, and other proces.es. A recent paper in Cell has.identified one member of this.family, s.X17, as.an es.ential factor for inducing the PGC lineage in ***, this.protein does.not appear to have a role in PGC s.ecification in mice. This.work not only introduces.a new and important player to the field of germ cell s.ecification, but als. emphas.zes.the uniquenes. of human PGC development compared to more extens.vely s.udied mous. models.

关键词： @@

Geochronology of the volcanic rocks.in the Lu-Zong bas.n and its.s.gnificance

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s.ience China Earth s.iences 2008年第10期51卷 1470-1482页

作者： David cooke s.bas.ien MEFFRE Centre of Excellence in Ore Depos.ts.(CODEs. University of Tasmania

The Lu-Zong (Lujiang-Zongyang) bas.n is.one of the mos. important volcanic bas.ns.in the middle and lower reaches.of the Yangtze River area, China. It compris.s.four s.os.onitic volcanic units. which are, in an as.ending order, the Longmenyuan, Zhuanqiao, s.uangmiao and Fus.an Groups. The LA-ICP Ms.U-Pb zircon ages.of the four units.are: 134.8±1.8 Ma for the Longmenyuan Group, 134.1±1.6 Ma for the Zhuanqiao Group, 130.5±0.8 Ma for the s.uangmiao Group, and 127.1±1.2 Ma for the Fus.an Group. The res.lts.indicate that all volcanic rocks.in the Lu-Zong bas.n were formed in the Early Cretaceous.from about 135 Ma to 127 Ma, las.ing 8-10 Ma. There were no Juras.ic volcanic activities.in all the volcanic bas.ns.including the Lu-Zong bas.n in the middle and lower reaches.of the Yangtze River area. This.work has.provided new chronological res.lts.for the further s.udy and unders.anding of the tec- tonic, magmatic and metallogenic proces.es.of eas.ern China in the Mes.zoic.

关键词： zircon LA-ICP Ms dating volcanic rocks geochronologic age Lu-Zong bas.n

An inexpens.ve underwater mine countermeas.res.s.mulator with real-time 3D after action review

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Defence Technology（防务技术） 2016年第5期12卷 367-379页

作者： Robert s.ONE Timothy s.ELL Neil cooke Human Interface Technologies.Team University of Birmingham UK Univers.ty of Birmingham UK

This.paper pres.nts.the res.lts.of a concept capability demons.ration pilot s.udy, the aim of which was.to inves.igate how inexpens.ve gaming s.ftware and hardware technologies.could be exploited in the development and evaluation of a s.mulator prototype for training Royal Navy mine clearance divers. s.ecifically focus.ng on the detection and accurate reporting of the location and condition of underwater ordnance. The s.mulator was.cons.ructed us.ng the Blender open s.urce 3D modelling toolkit and game engine, and featured not only an interactive 3D editor for underwater s.enario generation by ins.ructors. but als. a real-time, 3D After Action Review(AAR) s.s.em for formative as.es.ment and *** s.mulated s.enarios.and AAR architecture were bas.d on early human factors.obs.rvations.and briefings.conducted at the UK's.Defence Diving s.hool(DDs., an organis.tion that provides.bas.c military diving training for all Royal Navy and Army(Royal Engineers. divers. An experimental pilot s.udy was.undertaken to determine whether or not bas.c navigational and mine detection components.of diver performance could be improved as.a res.lt of expos.ng participants.to the AAR s.s.em, delivered between s.mulated diving s.enarios. The res.lts.s.gges. that the provis.on of AAR was.accompanied by s.gnificant performance improvements.in the pos.tive identification of s.mulated underwater ordnance(in contras. to non-ordnance objects. and on participants. des.ription of their location, their immediate in-water or s.abed context and their s.ructural condition. Only marginal improvements.were found with participants. navigational performance in terms.of their deviation accuracies.from a pre-programmed expert s.arch path. Overall, this.project contributes.to the growing corpus.of evidence s.pporting the development of s.mulators.that demons.rate the value of exploiting open s.urce gaming s.ftware and the s.gnificance of adopting es.ablis.ed games.des.gn techniques.in delivering highly

关键词： s.mulation Virtual reality Diver training Ordnance dis.os.l Mine clearance

Plas.icity of s.ermatogonial s.em cells

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As.an Journal of Andrology 2015年第3期17卷 355-359页

作者： Paul s.cooke Liz s.mon Manjunatha K Nanjappa Theres. I Medrano s.zanne E Berry Department of Phys.ological s.iences College of Veterinary Medicine University of Florida Gainesville FL 32608 USA Department of Phys.ology Louisiana State University Health Sciences Center New Orleans LA 70112 USA Department of Comparative Bios.iences College of Veterinary Medicine University of Illinois at Urbana-Champaign Urbana IL 61802 USA

There have been s.gnificant breakthroughs.over the pas. decade in the development and us. of pluripotent s.em cells.as.a potential s.urce of cells.for applications.in regenerative medicine. It is.likely that this.methodology will begin to play an important role in human clinical medicine in the years.to come. This.review des.ribes.the plas.icity of one type of pluripotent cell, s.ermatogonial s.em cells.（s.Cs., and their potential therapeutic applications.in regenerative medicine and male infertility. Normally, s.Cs.give ris. to s.erm when in the tes.is. However, both human and murine s.Cs.can give ris. to cells.with embryonic s.em （Es. cell-like characteris.ics.that can be directed to differentiate into tis.ues.of all three embryonic germ layers.when placed in an appropriate inductive microenvironment, which is.in contras. to other pos.natal s.em cells. Previous.s.udies.have reported that s.Cs.expres.ed an intermediate pluripotent phenotype before differentiating into a s.ecific cell type and that extended culture was.neces.ary for this.to occur. However, recent s.udies.from our group us.ng a tis.ue recombination model demons.rated that s.Cs.differentiated rapidly into another tis.ue, in this.cas., pros.atic epithelium, without expres.ion of pluripotent Es.cell markers.before differentiation. Thes. res.lts.s.gges. that s.Cs.are capable of directly differentiating into other cell types.without going through an intermediate Es.cell-like s.age. Becaus. s.Cs.do not require reprogramming to achieve a pluripotent s.ate, they are an attractive s.urce of pluripotent cells.for us. in regenerative medicine.

关键词： pluripotency regenerative medicine s.ermatogenes.s tes.is

Convection–Diffus.on Model for the Prediction of Anthropogenically-Initiated Wildfire Ignition

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International Journal of Dis.s.er Ris. s.ience 2014年第4期5卷 274-295页

作者： Ravi s.das.vuni s.anti Bhus.an William H.cooke Department of Geos.iences Mississippi State UniversityStarkvilleMS 39759USA Center for Advance Vehicular s.s.ems Mississippi State UniversityStarkvilleMS 39759USA

A s.atial interaction model to predict anthropogenically-initiated accidental and incendiary wildfire ignition probability is.developed us.ng fluid flow analogies.for human movement patterns. Urban areas.with large populations.are identified as.the s.tes.of global influencing factors. and are modeled as.the gravity term. The trans.ortation corridors.are identified as.local influencing factors. and are modeled us.ng fluid flow analogy as.diffus.on and convection terms. The model is.implemented in ArcGIs. and applied for the prediction of wildfire hazard dis.ribution in s.utheas.ern Mis.is.ippi. The model s.ows.7 % correlation with his.oric data in the winter s.as.n,whereas.the previous.y developed gravity model s.ows.only 75 % correlation. The normalized error for convection–diffus.on model predictions.is.about 5 % in the winter s.as.n, whereas.the gravity model s.ows.an error of 7 %.The propos.d model is.robus. as.it couples.a multi-criteria behavioral pattern within a s.ngle dynamic equation to enhance predictive capability. At the s.me time, the propos.d model is.more cos.ly than the gravity model as.it requires.evaluation of dis.ance from intermodal trans.ortation corridors. trans.ortation corridor dens.ty, and traffic volume maps. Nonetheles., the model is.developed in a modular fas.ion, s.ch that either global or local terms.can be neglected if required.

关键词： Anthropogenic-fire Convection–diffus.on model Fire ignition potential Mis.is.ippi Wildfire hazard

A parametric s.udy of the hydrodynamic roughnes. produced by a wall coating layer of heavy oil

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Petroleum s.ience 2017年第1期14卷 155-166页

作者： s. Rus.d R. s. s.nders Department of Chemical and Materials.Engineering University of Alberta Edmonton AB Canada

In water-lubricated pipeline trans.ortation of heavy oil and bitumen, a thin oil film typically coats.the pipe wall. A detailed s.udy of the hydrodynamic effects.of this.fouling layer is.critical to the des.gn and operation of oil-water pipelines. as.it can increas. the pipeline pres.ure los. （and pumping power requirements. by 15 times.or more. In this.s.udy, a parametric inves.igation of the hydrodynamic effects.caus.d by the wall coating of vis.ous.oil was.conducted. A cus.om-built rectangular flow cell was.us.d. A validated CFD-bas.d procedure was.us.d to determine the hydrodynamic roughnes. from the meas.red pres.ure los.es. A s.milar procedure was.followed for a s.t of pipe loop tes.s. The effects.of the thicknes. of the oil coating layer, the oil vis.os.ty, and water flow rate on the hydrodynamic roughnes. were evaluated. Oil vis.os.ties.from 3 to 21300 Pa s.were tes.ed. The res.lts.s.ow that the equivalent hydrodynamic roughnes. produced by a wall coating layer of vis.ous.oil is.dependent on the coating thicknes. but es.entially independent of oil vis.os.ty. A new correlation was.developed us.ng thes. data to predict the hydrodynamic roughnes. for flow conditions.in which a vis.ous.oil coating is.produced on the pipe wall.

关键词： Pipeline trans.ortation - Heavy oil Wallfouling Lubricated pipe flow CFD s.mulation

Firs. principles.ins.ghts.into oxide/polymer compos.tes. s.TiO_(3) /polyaniline/graphene

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Journal of Materials.s.ience & Technology 2023年第35期166卷 250-260页

作者： Nathan D.Wood Jos.ua s.Ts. Jonathan M.s.elton David J.cooke Lis. J.Gillie s.ephen C.Parker Marco Molinari Department of Chemical s.iences School of Applied SciencesUniversity of HuddersfieldHuddersfield HD13DHUK Department of Chemis.ry University of ManchesterManchester M139PLUK Department of Chemis.ry University of BathBath BA27AYUK

A detailed computational inves.igation,bas.d on dens.ty functional theory,of the interaction of polyani-line(PANI)and graphene nanoribbons.GNRs.with s.TiO_(3) is.*** ads.rption of PANI in var-ious.oxidation s.ates.and co-ads.rption with GNRs.is.found to be thermodynamically ***-s.rbed PANI introduces.N and C 2p s.ates.into the s.TiO_(3) bandgap,while co-ads.rption of PANI and GNRs.leads.to a bridging of the gap and s.mi-metallic behaviour,thus.rendering the electrical properties.highly s.ns.tive to the loading of the GNRs.PANI in the *** the lattice dynamics.of the compos.tes.predicts.a 68-88%reduction in the lattice thermal conductivity due to reduced phonon group *** together,thes. findings.provide ins.ght into the growing number of experimental s.udies.highlighting the enhanced thermoelectric performance of oxide-polymer compos.tes.and indicate co-ads.rption with graphene as.a facile direction for future res.arch.

关键词： Polymer/inorganic compos.tes Polyaniline/s.rontium titanate/graphene nanoribbon compos.tes PANI/GNR/s.TiO_(3)compos.tes Thermoelectric compos.tes Electrical trans.ort Thermal conductivity1 Introduction

As.ociation between growth rates. age at firs. calving and s.bs.quent fertility, milk production and s.rvival in Hols.ein-Fries.an heifers

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Open Journal of Animal s.iences 2013年第1期3卷 1-12页

作者： Jes.ica s. cooke Zhangrui Cheng Nicola E. Bourne D. Claire Wathes Royal Veterinary College Hatfield UK

Age at firs. calving (AFC) affects.the profitability of dairy enterpris.s. This.s.udy examined the relations.ips.between AFC and s.bs.quent fertility, milk production and s.rvival up to third calving in UK Hols.ein-Fries.an heifers.s.udy 1 compris.d 134 cons.cutively born heifers.from the s.me herd (AFC 764 ± 8 days. and s.udy 2 contained 445 heifers.born on 17 farms.(AFC 796 ± 6 days.. Growth rates.and fertility during rearing were monitored and animals.were s.bs.quently divided into four AFC groups.for analys.s. s. 23 - 25 months. 26 - 30 months.and >30 months. The actual AFC reflected both growth rate and heifer fertility, with later calving heifers.already lighter by 6 months.of age. The proportion conceiving to firs. s.rvice was.highes. (93% and 84% for s.udies.1 and 2, res.ectively) for the younges. AFC group. Fertility in the firs. lactation was.bes. in cows.calving at 23 - 25 months.and wors. in the oldes. AFC group. Milk production parameters.in the firs. and s.cond lactations.were broadly s.milar between AFC groups.but s.gnificantly more heifers.with an AFC s.calved for a third time. Thes. younger calving animals.therefore achieved more days.in milk over 5 years. with >44% of their days.alive s.ent in milk production compared with only 18% - 40% in cows.calving at ≥26 months. Hence cows.with an AFC s.produced the mos. milk in their firs. 5 years.of life. Thes. res.lts.indicate that an AFC of 0.75 kg/d up to 15 months.and good heifer fertility and res.lted in the bes. s.bs.quent performance.

关键词： Age at Firs. Calving Heifer Fertility Milk Production Longevity