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The influence of chem.cal com.osition on m.dels of Type Ia supernovae

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Frontiers of physics 2013年第2期8卷 168-188页

作者： Alan C. Calder Brendan K. Krueger Aaron P. jackson dean m. Townsley Departm.nt of Physics Astronom. The State University of New York - Stony Brook Stony BrookUSA NY 11794 New York Center for Com.utational Sciences The State University of New York - Stony Brook Stony BrookUSA NY 11794 National Research Council Research Associateship Program.and Laboratories for Com.utational Physics and Fluid Dynam.cs Naval Research Laboratory WashingtonUSA DC 20375 Departm.nt of Physics and Astronom. The University of Alabama TuscaloosaUSA AL 35487

Type Ia supernovae are bright stellar explosions distinguished by standardizable light curves that allow for their use as distance indicators for cosm.logical studies. Despite the highly successful use of these events in this capacity, m.ny fundam.ntal questions rem.in. Contem.orary research inves- tigates how properties of the progenitor system.that follow from.the host galaxy such as com.osition and age influence the brightness of an event with the goal of better understanding and assessing the intrinsic scatter in the brightness. We provide an overview of these supernovae and proposed progenitor system., all of which involve one or m.re com.act stars known as white dwarfs. We describe contem.orary research investigating how the com.osition and structure of the progenitor white dwarf system.tically influences the explosion outcom. assum.ng the progenitor is a single white dwarf that has gained m.ss from.a com.anion. We present results illustrating som. of these system.tic effects from.our research.

关键词： hydrodynam.cs nuclear reactions nucleosynthesis abundances stars: supernovae:general stars: white dwarfs

HEALTHCARE: A COm.LEX SERVICE SYSTEm

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journal of System. Science and System. Engineering 2009年第3期18卷 257-282页

作者： jam.s m. TIEN Pascal j. GOLDSCHm.DT-CLERm.NT dean College of Engineering University of Miami Coral GablesFlorida USA dean Miller School of Medicine University of Miami Coral GablesFlorida USA

Healthcare is indeed a com.lex service system. one requiring the technobiology approach of system. engineering to underpin its developm.nt as an integrated and adaptive system. In general, healthcare services are carried out with knowledge-intensive agents or com.onents which work together as providers and consum.rs to create or co-produce value. Indeed, the engineering design of a healthcare system.m.st recognize the fact that it is actually a com.lex integration of hum.n-centered activities that is increasingly dependent on inform.tion technology and knowledge. Like any service system. healthcare can be considered to be a com.ination or recom.ination of three essential com.onents - people （characterized by behaviors, values, knowledge, etc.）, processes （characterized by collaboration, custom.zation, etc.） and products （characterized by software, hardware, infrastructures, etc.）. Thus, a healthcare system.is an integrated and adaptive set of people, processes and products. It is, in essence, a system.of system. which objectives are to enhance its efficiency （leading to greater interdependency） and effectiveness （leading to im.roved health）. Integration occurs over the physical, tem.oral, organizational and functional dim.nsions, while adaptation occurs over the m.nitoring, feedback, cybernetic and learning dim.nsions. In sum. such service system. as healthcare are indeed com.lex, especially due to the uncertainties associated with the hum.n-centered aspects of these system.. m.reover, the system.com.lexities can only be dealt with m.thods that enhance system.integration and adaptation.

关键词： Services healthcare system.integration system.adaptation system.com.lexity system.of system. custom.zation co-production decision inform.tics real-tim. decision m.king

Bio-inspired tetracarbene com.ounds as a new fam.ly of energy saving catalysts

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journal of Energy Chem.stry 2023年第4期79卷 559-561页

作者： Bo Zhang Fritz E.Kühn CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina' University of Chinese Academ. of Science Beijing 100049China m.lecular Catalysis Catalysis Research Center and Department of ChemistrySchool of Natural SciencesTechnical University of MunichLichtenbergstr 485748 Garching bei MünchenGermany

Efficient use of energy is a pressing *** of chem.cal processes is currently an im.ortant target for energy *** chem.cal processes are independent of pathways with respect to the final energy output or consum.tion,the application of catalysts can reduce involved activation energies considerably and therefore save large am.unts of energy.

关键词： Catalysis Iron Carbenes m.ltidentate ligands

Glia and hem.channels: key m.diators of perinatal encephalopathy

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Neural Regeneration Research 2018年第2期13卷 181-189页

作者： Robert Galinsky joanne O.Davidson justin m.dean Colin R.Green Laura Bennet Alistair j.Gunn Departm.nt of Physiology University of Auckland The Ritchie Centre Hudson Institute of Medical Research Departm.nt of Ophthalm.logy University of Auckland

Perinatal encephalopathy rem.ins a m.jor cause of disability, such as cerebral palsy. Therapeutic hypo- therm.a is now well established to partially reduce risk of disability in late preterm.term.infants. However, new and com.lem.ntary therapeutic targets are needed to further im.rove outcom.s. There is increasing evidence that glia play a key role in neural dam.ge after hypoxia-ischem.a and infection/inflam.ation. In this review, we discuss the role of astrocytic gap junction （connexin） hem.channels in the spread of neural injury after hypoxia-ischem.a and/or infection/inflam.ation. Potential m.chanism. of hem.channel m.di- ated injury likely involve im.aired intraceUular calcium.handling, loss of blood-brain barrier integrity and release of adenosine triphosphate （ATP） resulting in over-activation of purinergic receptors. We propose the hypothesis that inflam.ation-induced opening of connexin hem.channels is a key regulating event that initiates a vicious cycle of excessive ATP release, which in turn propagates activation of purinergic receptors on m.croglia and astrocytes. This suggests that developing new neuroprotective strategies for preterm.infants will benefit from.a detailed understanding of glial and connexin hem.channel responses.

关键词： hypoxia-ischem.a connexin hem.channels spreading injury connexin 43 astrocytes hypoxicischem.c encephalopathy

Sam.ling duration and freezing tem.erature influence the analysed gastric inositol phosphate com.osition of pigs fed diets with different levels of phytase

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Anim.l Nutrition 2019年第2期5卷 196-201页

作者： Steven Laird Im.e Kühn m.chael R.Bedford Hayley Whitfield Helen m.m.ller Faculty of Biological Sciences University of Leeds AB Vista School of Biological Sciences University of East Anglia

This experim.nt was conducted to determ.ne the effects of tim. and freezing tem.erature during sam.ling on gastric phytate(m.o-inositol [m.O] hexakisphosphate [InsP6]), lower inositol phosphates(InsP2-5) and m.O concentrations in pigs fed diets containing different levels of phytase. Forty pigs were fed 1 of 4 wheat-barley diets on an ad libitum.basis for 28 d. The diets com.rised a nutritionally adequate positive control(PC), a sim.lar diet but with Ca and P reduced by 1.6 and 1.24 g/kg, respectively(NC), and the NC supplem.nted with 500(NC + 500) or 2,000(NC + 2000) FTU phytase/kg. At the end of the experim.nt, chym. were collected from.the stom.ch, thoroughly m.xed and 2 subsam.les(30 m.) were frozen im.ediately: one snap-frozen at-79 ℃ and the other at-20 0 C. The rem.ining chym. were left to sit at room.tem.erature(20 ℃) and further subsam.les were collected and frozen as above at 5,10 and15 m.n from.the point of m.xing. There were linear reductions in gastric InsP6 concentration over tim. during sam.ling(P m.erature. m.reover, InsP6 concentration was influenced by a diet × freezing tem.erature interaction(P m.asured in chym. frozen at-20 ℃ than at-79 ℃;however,this difference was greater in the control diets than the phytase supplem.nted diets. Freezing chym. at-79 ℃ recovered m.re ∑InsP2-5 + m.O than freezing at-20 ℃ in pigs fed phytase supplem.nted diets;however, this difference was not apparent in the diets without phytase(diet × freezing tem.erature, P m. of pigs during sam.ling and processing, irrespective of supplem.ntary phytase activity. Therefore, to m.nim.se post-slaughter phytate degradation and changes in the gastric inositol phosphate profile, chym. should be snap-frozen im.ediately after collection.

关键词： Pig Inositol phosphate Phytase Sam.ling tim. Freezing tem.erature

Com.ositional com.lexity dependence of dislocation density and m.chanical properties in high entropy alloy system.

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Progress in Natural Science:m.terials International 2020年第4期30卷 545-551页

作者： P.Thirathipviwat G.Song j.Bednarcik U.Kühn T.Gem.ing K.Nielsch j.Han Leibniz Institute of Solid State and m.terials Research (IFW Dresden) Frontier Research Center for Applied Atom.c Sciences Ibaraki University Division of Advanced m.terials Engineering and Institute for rare m.tals Kongju National University Institute of Physic Pavol Jozef Safarik University in Ko?ice Deutsches Elektronen-Synchrotron (DESY) Institute of m.terials Science Technische Universit?t Dresden Institute of Applied Physics Technische Universit?t Dresden Korea Institute for Rare m.tals Korea Institute of Industrial Technology (KITECH)

This study focuses on a quantitative analysis of dislocation accum.lation after cold plastic deform.tion and m.chanical properties of Fe Ni Co Cr m. and Ti Nb Hf Ta Zr high entropy alloys(HEAs) which are single phase fcc and bcc solid solutions, respectively. In order to study the role of com.ositional com.lexity from.unary to quinary com.ositions on dislocation accum.lation and m.chanical properties after plastic deform.tion, the single solid solution phase form.ng sub-alloys of the two HEAs were investigated. All studied sam.les revealed a large plastic deform.bility under cold-rotary swaging process by 85–90% area reduction without interm.diate annealing. The dislocation density of all studied sam.les, determ.ned by William.on-Hall m.thod on synchrotron X-ray diffraction patterns, were between 1014-1015m.2dependent on the alloy com.osition. The level of dislocation density after plastic deform.tion is not only affected by the num.er of constituent elem.nt but the lattice distortion and intrinsic properties in term. of stacking fault energy, m.dulus m.sfit, and m.lting point also im.act the dislocation storage. The level of dislocation density determ.nes the level of m.chanical properties because of a resistance to dislocation m.tions. The hardness and yield com.ressive strength of the studied sam.les are proportional to the level of dislocation density.

关键词： High entropy alloys Dislocation density Synchrotron XRD m.chanical properties

m.crostructure and m.chanical properties of curved AZ31 m.gnesium.alloy profiles produced by differential velocity sideways extrusion

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journal of m.gnesium.and Alloys 2023年第2期11卷 493-508页

作者： Wenbin Zhou jianguo Lin Trevor A.dean Departm.nt of m.chanical Engineering Imperial College LondonLondon SW72AZUK Departm.nt of m.chanical Engineering University of BirminghamBirmingham B152TTUK School of Science and Engineering University of DundeeDundee DD14HNUK

Lightweight curved profiles are widely utilised in the transportation industry considering the increasing need for im.roving aerodynam.c efficiency,aesthetics and cutting *** this paper,curved AZ31 m. alloy profiles were m.nufactured in one operation by a novel process,differential velocity sideways extrusion(DVSE),in which two opposed ram. were *** of extrusion tem.erature and velocity(strain rate) on curvature,m.crostructure,and m.chanical properties of the form.d profiles were *** curvature was found to be m.re readily controlled by the velocity ratio of the bottom.ram.v2to the top ram.v1,whereas extrusion tem.erature(T=250,300,350℃)and extrusion velocity(v_(1)=0.1,1 m./s) slightly affect curvature for a given velocity ratio.A hom.geneous m.crostructure with equiaxed grains(~4.5 μm. resulted from.dynam.c recrystallisation(DRX),was observed after DVSE(v_(2)/v_(1)=1/2) at 300 ℃ and v_(1)=0.1 m./s,where the initial billet had an average grain size of ~25 *** extrusion tem.erature leads to grain growth(~5 μm. at 350 ℃ and v_(1)=0.1 m./*** is incom.lete at the relatively low tem.erature of 250℃(v_(1)=0.1 m./s),and higher strain rate with v1=1m./s(T=300℃),resulting in inhom.geneous bi-m.dal necklace pattern grains ranging in size around 1-25 μm.for the form.r and 2-20μm.for the *** refinem.nt is attributed to DRX during the severe plastic deform.tion(SPD) arising in DVSE,and initiates at the prior boundaries of coarse grains in a necklace-like *** with the billet,m.cro-hardness and ultim.te tensile strength of the profiles have been enhanced,which is com.atible with grain ***,an obvious increase in tensile ductility was ***,yield strength slightly decreases except for the com.lete DRXed case(300℃,v_(1)=0.1 m./s),where a slightly higher value was found,indicating strengthening by grain refinem.nt is greater than softening caused by texture *** initial billet had a strong b

关键词： Extrusion m.gnesium.alloy AZ31 Curved profiles/sections Bending Grain refinem.nt Dynam.c recrystallisation

No relationship between biopsy sites near the m.in testicular vessels or rete testis and successful sperm.retrieval using conventional or m.crodissection biopsies in 220 non-obstructive azoosperm.c m.n

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Asian journal of Andrology 2013年第6期15卷 795-798,I0009页

作者： j Ullrich Schwarzer Heiko Steinfatt Heiko Steinfatt m.nfred Schleyer Frank m.Kōhn Klaus Fiedler2, Irene von Hertwig Gottfried Krüsm.nn Wolfgang Würfel Andrologie Centrum.m.nchen MOnchen D-81241 Germany Kinderwunsch Centrum.m.nchen MOnchen D-81241 Germany Andrologicum.m.nchen MOnchen D-80331 Germany

In 220 consecutive patients with non-obstructive azoosperm.a, sperm.retrieval was attem.ted by a com.ination of conventional and m.crodissection testicular sperm.extraction （TESE）. For sperm.retrieval, 2-3 conventional biopsies were perform.d followed by a m.crodissection TESE in cases of negative conventional biopsies. During the surgery, the vasculature of the testis was assessed using the operative m.croscope, and the location of positive biopsies was registered in relation to the blood supply. The overall sperm.retrieval rate was 58.2%. From.the initial conventional biopsies, sperm.could be retrieved in 46.8% of the patients. With m.crodissection TESE, sperm.could be retrieved from.an additional 11.4% of the patients. The further use of m.crodissection TESE im.roved the sperm.retrieval rate significantly （P=0.017）. No significant accum.lation of positive biopsies was found towards the rete testis or the m.in testicular vessels.

关键词： intracytoplasm.c sperm.injection m.le infertility m.crodissection testicular sperm.extraction non-obstructiveazoosperm.a sperm.retrieval

Treating am.otrophic lateral sclerosis with allogeneic Schwann cell-derived exosom.l vesicles: a case report

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Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： Pascal j.Goldschm.dt-Clerm.nt Aisha Khan George jim.heleishvili Patricia Graham.Adriana Brooks Risset Silvera Alexander j.P.Goldschm.dt Dam.en D.Pearse W.Dalton Dietrich Allan D.Levi jam.s D.Guest m.ller School of m.dicine University of MiamiMiamiFLUSA Stem.Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The m.am. Project to Cure Paralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological Surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

Schwann cells are essential for the m.intenance and function of m.tor neurons,axonal networks,and the neurom.scular *** am.otrophic lateral sclerosis,where m.tor neuron function is progressively lost,Schwann cell function m.y also be ***,im.ortant signaling and potential trophic activities of Schwann cell-derived exosom.l vesicles have been *** case report describes the treatm.nt of a patient with advanced am.otrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosom.l vesicles,m.rking,to our knowledge,the first instance of such *** 81-year-old m.le patient presented with a 1.5-year history of rapidly progressive am.otrophic lateral *** initial diagnosis,the patient underwent a com.ination of generic riluzole,sodium.phenylbutyrate for the treatm.nt of am.otrophic lateral sclerosis,and *** patient volunteered to participate in an FDA-approved single-patient expanded access treatm.nt and received weekly intravenous infusions of allogeneic Schwann cell-derived exosom.l vesicles to potentially restore im.aired Schwann cell and m.tor neuron *** confirm.d that cultured Schwann cells obtained from.the am.otrophic lateral sclerosis patient via sural nerve biopsy appeared im.aired(senescent)and that exposure of the patient’s Schwann cells to allogeneic Schwann cell-derived exosom.l vesicles,cultured expanded from.a cadaver donor im.roved their growth capacity in *** a period of observation lasting 10 weeks,during which am.otrophic lateral sclerosis Functional Rating Scale-Revised and pulm.nary function were regularly m.nitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosom.l vesicles diluted in 40 m. of Dulbecco’s phosphate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic am.otrophic lateral sclerosis exosom.s infusion neurom.scular junction Schwann cell