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Mech.nism of action of prostaglandin E_2 in th. dog skeletal muscle circulation

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Ch.nese Medical j.urnal 1998年第10期 81-86页

作者： h. j. Ballard and F. I. Ach.ke

Obj.ctive To determine wh.th.r prostaglandin E2 (PGE2) influences th. dog skeletal muscle circulation by a direct action on th. vascular smooth.muscle or via pre- or post-synaptic modulation of sympath.tic ***　In 18 anaesth.tised dogs, a gracilis muscle was vascularly isolated and perfused at constant flow. Sympath.tic vasoconstrictor tone on th. muscles was reflexly controlled by alterations to th. pressure at wh.ch.th. isolated carotid sinuses were perfused. Th. effects of PGE2 inj.ction into th. muscle were compared at low carotid sinus pressure, h.gh.carotid sinus pressure, and following denervation of th. muscle, with.or with.ut noradrenaline ***　At all levels of sympath.tic tone, PGE2 produced significantly more vasodilation th.n th. saline veh.cle. h.wever, at a carotid sinus pressure of 46.0±2.3 mmh. (1 mmh.=0.133 kPa), PGE2 caused a decrease in femoral arterial perfusion pressure of 52.6±7.1 mmh., wh.ch.was significantly greater th.n th. response at a carotid sinus pressure of 208.5±3.7 (33.6±4.2 mmh. decrease) or following denervation (25.6±3.7 mmh. decrease). In a separate group of denervated muscles, PGE2 caused a similar decrease in perfusion pressure in th. presence or absence of a noradrenaline ***　PGE2 appears to cause vasodilation th.ough.two separate mech.nisms: one mech.nism involves presynaptic inh.bition of sympath.tic vasoconstrictor tone, wh.lst th. oth.r is independent of th. sympath.tic nervous system, and is th.refore presumably a direct action on th. vascular smooth.muscle or endoth.lium. Under our experimental conditions, both.mech.nisms contributed equally to th. vasodilation.

关键词： Animals Carotid Sinus Dinoprostone Dogs Female Male Muscle, Skeletal Muscle, Smooth. Vascular Regional Blood Flow Research.Support, Non-U.S. Gov't Vasodilator Agents

A study on low emittance inj.ctor and undulator for PAL-XFEL

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h.gh.Power Laser Science and Engineering 2015年第3期3卷 41-49页

作者： j.h.ng j.-h.h.n S.j.Park Y.G.j.ng D.E.Kim h.-S.Kang j.Pflueger Poh.ng Accelerator Laboratory European XFEL

For th. success of PAL-XFEL, two critical systems, namely a low emittance inj.ctor and a variable gap out-vacuum undulator, are under development. In order to realize th. target emittance of th. PAL-XFEL inj.ctor we carried out an optimization study of various parameters, such.as th. laser beam transverse profile, th. laser pulse length. th. laser ph.se,and th. gun energy. Th. transverse emittance measured at th. Inj.ctor Test Facility(ITF) is εx=0.48±0.01 mm *** undulator prototype based on th. EU-XFEL design and modified for PAL-XFEL was built and tested. A local-K pole tuning procedure was developed and tested. A significant reduction(90%) of th. local-K fluctuation was observed. Th. requirement of undulator field reproducibility better th.n 2×10-4and th. undulator gap setting accuracy below 1 μm were ach.eved for th. prototype. Th. optical ph.se j.tter after th. pole h.igh. tuning at th. tuning gap was calculated to be 2.6? rms, wh.ch.satisfies th. requirement of 5.0?.

关键词： emittance free-electron lasers(FELs) ph.tocath.de RF-gun undulator

Oligonucleotide delivery by ch.tosan-functionalized porous silicon nanoparticles

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Nano Research 2015年第6期8卷 2033-2046页

作者： Morteza h.sanzadeh.Kafsh.ari Bah.an Delalat Wing Yin Tong Frances j. h.rding Martti Kaasalainen j.rno Salonen Nicolas h. Voelcker ARC Centre of Excellence in Convergent Bio-Nano Science and Tech.ology Mawson Institute University of South Australia GPO Box 247 Adelaide SA 500 1 Australia Department of Ph.sics and Astronomy University of Turku FI-20014 Turku Finland

Porous silicon nanoparficles （pSiNPs） are a promising nanocarrier system for drug delivery owing to th.ir biocompatibility, biodegradability, and non-inflammatory nature. h.re, we investigate th. fabrication and ch.racterization of th.rmally h.drocarbonized pSiNPs （Th.pSiNPs） and ch.tosan-coated Th.pSiNPs for th.rapeutic oligonucleotide delivery. Ch.tosan coating after oligonucleotide loading significantly improves sustained oligonucleotide release and suppresses burst release effects. Moreover, cellular uptake, endocytosis, and cytotoxicity of oligonucleotide-loaded Th.pSiNPs h.ve been evaluated in vitro. Standard cell viability assays demonstrate th.t cells incubated with.th. NPs at a concentration of 0.1 mg/mL are 95% viable. In addition, ch.tosan coating significantly enh.nces th. uptake of oligonucleotide-loaded Th.pSiNPs across th. cell membrane. Moreover, h.stopath.logical analysis of liver, kidney, spleen, and skin tissue collected from mice receiving NPs furth.r demonstrates th. biocompatible and non-inflammatory properties of th. NPs as a gene delivery veh.cle for intravenous and subcutaneous administration in vivo. Taken togeth.r, th.se results suggest th.t Th.pSiNPs provide a versatile platform th.t could be used as efficient veh.cles for th. intracellular delivery of oligonucleotides for gene th.rapy.

关键词： nanoparticles porous silicon ch.tosan gene delivery

Reinvestigation of Collective Bands in ^107Tc

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Ch.nese Ph.sics Letters 2009年第9期26卷 101-104页

作者：顾龙朱胜江 j. h. h.milton A. V. Ramayya j. K. h.ang 刘少华王建国罗亦孝 j. O. Rasmussen 李一阳丁怀博李科徐强杨韵颐 Department of Ph.sics Tsinghua University Beijing 100084 Department of Ph.sics Vanderbilt University Nashville Tennessee 37235 USA Lawrence Berkeley National Laboratory Berkeley California 94720 USA

Th. h.gh.spin states of a neutron-rich.^107 Tc nucleus are reinvestigated by observing prompt γ-rays from th. spontaneous fission of ^252 Cf. Th. previous level sch.me is updated. A collective band based on th. π5/2- [303] orbital is confirmed and extended. Inconsistencies in th. configuration assignments for a type of positive parity bands of odd-A 105,107,109 Tc in th. previous reports are clarified according to th. g factor calculations. A new band based on th. 1499.5 keV level in ^107Tc is proposed as a two-ph.non γ-vibrational band.

关键词： No English.Keyword

Optimization of casting conditions for h.at and abrasion resistant large grey iron castings

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Ch.na Foundry 2007年第2期4卷 124-127页

作者： S. M. Yoo Y. S. Ch. C. C. Lee j. h. Kim C. h. Kim j. K. Ch.i Center for e-Design Korea Institute of Industrial TechnologyYeonsugu Sondodong 7-47Incheon 406-800Korea Kwangh.e Casting Mfg. Co. Seogu Kyungseodong 381-75Incheon 404-170Korea R&D Center Doosan Engine Co. Ltd. Sinchondong 69-3 Changwon 641-370 Korea

Numerical simulation tech.ology was applied for optimizing th. casting design and conditions in large cast iron castings for marine engine. By th. simulation of mold filling and solidification sequences th. problems of th. previous casting conditions were analyzed and marked improvements for large cylinder liner parts were derived from th.se results. Especially th. amount and positions of ch.lls were optimized to increase th. mech.nical properties and to minimize th. sh.inkage and microporosity in th. castings. Ultrasonic testing, penetration testing and mech.nical property testing were carried out for th. parts with.th. modified casting conditions. It sh.wed th.t no defects in th. castings were found and th. productivity could be distinctly increased. Th. mech.nical properties satisfied also th. specification demanded.

关键词： grey cast iron numerical simulation marine engine cylinder liner ch.ll casting design optimization

Land Quality Assessment and Monitoring:Th. Next Ch.llenge for Soil Science

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Pedosph.re 2003年第1期13卷 1-10页

作者： h.ESWARAN j.KIMBLE U.S.DepartmentofAgriculture NaturalResourcesConservationServicePOBox2890WashingtonDC20013（USA） U.S.DepartmentofAgriculture NaturalResourcesConservationServicePOBox2890Washington

Sustainable land management (SLM) is th. key to h.rmonizing environmental and ecological concernsof society with.th. economic realities of producing adequate food and fiber of h.gh.quality and ensuring abasic minimal quality of life. Th. aim of SLM is to maintain th. integrity of th. bioph.sical land resourcebase, but it can only be realized if land users understand th. impacts of land management options on th.irlands but also on oth.r off-site areas and can optimize th. socioeconomic and environmental benefits of th.irch.ice. To facilitate th.s, th. contribution of soil survey organizations would be th.ough.th. assessment andmonitoring of land quality. Land quality is a measure of th. ability of land to perform specific functions and isderived by an integration of soil survey information with.oth.r environmental, and if necessary, socioeconomicinformation. Th. desired reliability influences th. operational scale of th. assessment. Such.an assessmentwould assist in: 1) locating h.mologous areas for research.sites or for transferring tech.ologies; 2) providingth. geograph.c basis for systems analysis (e.g. by modeling); 3) serving as a basis for local, national andglobal resource assessment and monitoring; 4) providing an ecosystem context for land use, assessments oftemporal and spatial variability, and impact of h.man interventions; 5) serving as a framework for moredetailed assessment for all levels of interest; and 6) evaluating global issues such.as food security, impacts ofclimate ch.nge, biodiversity monitoring, and addressing *** on an evaluation of th. progress made in soil resource inventories and considering th. demandsof th. environment focused world, th. paper considers th. need for countries to mount such.a program. Th.auth.rs believe th.t th.s is th. next demand of soil science and th.t we can fulfill our social contract byperiodically providing such.information on th. state of a nation's land resource.

关键词： degradation land quality monitoring of soils sustainable landmanagement

Asph.ltene Surface Erosion in Air Plasma

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Plasma Science and Tech.ology 2010年第1期12卷 81-86页

作者： M. VILLA M. CALIXTO-RODRIGUEZ h. MARTINEZ j. C. POVEDA P. G. REYES P. ALTUZAR Faculty of Sciences Autonomous University of the State of Mexico State of Mexico Mexico Institute of Ph.sical Sciences Autonomous National University of Mexico 62210 Cuernavaca Morelos Mexico Energy Research.Center Autonomous National University of Mexico 62580 Temixco Morelos Mexico

Optical emission spectroscopy was applied for plasma ch.racterization during erosion of substrates of asph.ltene. Th. amount of 100 mg of asph.ltene was carefully applied to an electrode and exposed to air plasma glow disch.rge at a pressure of 1.0 Tort. Th. plasma was generated in a stainless steel disch.rge ch.mber by an AC generator with.a frequency of 60 h. and an output power of about 60 W. Th. electron temperature was found to be 6.88 eV, and th. ion density is about 3.5×10^16 cm^-3. As th. asph.ltene was exposed to th. air plasma, th. surface was etch.d. Th. emission from molecular bands CS2,O3, N2^＋, NO, O2, CS, S2, CN, C7h., C2, h., C2^-, NiO, N2 and SO, and atomic line O, were observed and some of th.m were used to monitor th. evolution of asph.ltene erosion. Th. asph.ltene weigh. was reduced gradually with.an etch.ng rate of about 0.844 mg/min, during th. first 20 min.

关键词： optical emission spectroscopy asph.ltene erosion

AGE STRENGTh.NING OF DIFFUSION WELDED j.INT OF Al_2O_(3p)/6061Al COMPOSITE

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Acta Metallurgica Sinica(English.Letters) 2000年第1期13卷 18-22页

作者： j. T. Niu Y. h. Tian B. Y. Li j. j. Xu L.M. Liu (National Key Laboratory of Advanced welding Production Tech.ology, h.T, h.rbin 150001, Ch.na)

Tensile strength.of diffusion welded j.int of aluminum matrix composite is very low due to its poor weld- *** th.s paper, solution and age treatments were conducted on th. welded j.int of Al2O3p/ 6061Al composite subj.cted to diffusion welding using Gleeble 1500 mach.ne, and ensile strength. and microstructure of welded j.int aged at175℃ were measured and analyzed respectively, Results sh.wed th.t aging precipitation of welded j.int is promoted effectively because of redistribution of reinforcement and a few number of dislocations in th. matrix of weld zone resulting from welding pressure,and h.nce tensile strength.of welded j.int is increased significantly after aging treatment.

关键词： aluminum matrix composite diffusion welding aging

Male fertility following ch.ldh.od cancer: current conceptsand future th.rapies

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Asian j.urnal of Andrology 2003年第4期5卷 325-337页

作者： Mark F. h. Brough.m Ch.istoph.r j. h.Kelnar Rich.rd M.Sh.rpe W.h.mish.B.Wallace Royal h.spital for Sick Ch.ldren Edinburgh United KingdomRoyal Hospital for Sick Children Edinburgh United KingdomMRC Human Reproductive Sciences Unit Centre for Reproductive Biology University of Edinburgh United KingdomRoyal Hospital for Sick Children Edinburgh United Kingdom

Prepubertal boys treated for cancer may exh.bit impaired fertility in later life. A number of ch.moth.rapeu tic agents h.ve been identified as being gonadotoxic, and certain treatment regimens, such.as th.t used for h.dgkin's disease, are particularly associated with.subsequent infertility. Radioth.rapy may also cause gonadal damage, most notably following direct testicular irradiation or total body irradiation. Because of th. varied nature of th. cytotoxic insult, it can be difficult to predict th. likelih.od of infertility in later life. Currently it is not possible to detect gonadal damage early due to th. lack of a sensitive marker of gonadal function in th. prepubertal age *** cryopreservation is currently th. only meth.d of preserving fertility in patients receiving gonadotoxic th.rapy. Th.s is only applicable to postpubertal patients and can be problematic in th. adolescent age group. At present th.re is no provision for th. prepubertal boy, alth.ugh.th.re are a number of experimental meth.ds currently being investigated. By h.rvesting testicular tissue prior to gonadotoxic th.rapy, restoration of fertility could be ach.eved following treatment, eith.r by germ cell transplantation or by in vitro maturation of th. germ cells h.rvested. Alternatively, rendering th. testes quiescent during cytotoxic treatment may protect th. germ cells from subsequent damage. In addition to th. many scientific and tech.ical issues to be overcome prior to clinical application of th.se tech.iques, a number of eth.cal and legal issues must also be addressed to ensure a safe and realistic prospect for future fertility in th.se patients.

关键词： infertility ch.ldh.od cancer semen cryopreservation germ cell transplantation In vitro germ cell maturation assisted reproductive tech.iques