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Alternating-current losses in two-layer superconducting cables consisting of second-generation superconductors coated by U-shaped ferromagnetic materials

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Chinese Physics B 2013年第12期22卷 509-513页

作者： Ahmet Cicek Fedai Inanir Fedor Gm.ry Department of Physics Faculty of Arts and Sciences Mehmet Akif Ersoy University Department of Physics Faculty of Arts and Sciences Recep Tayyip Erdog an University Institute of Electrical Engineering Slovak Academy of Sciences Du'bravska' Cesta 9 842 39 Bratislava Slovakia

Alternating-current losses in a two-layer superconducting cable, each layer being composed of 15 closely-spaced rectangular wires made up of second-generation superconductors when the ends of wires are coated by either a non-magnetic or strong ferromagnetic material having a U profile is numerically investigated. Computations are carried out through the finite-element method. The alternating-current losses do not increase significantly if the relative permeability of the coating is increased three orders of magnitude, provided that the current amplitude is less than half of the critical current in a superconducting wire. However, the losses are much higher for ferromagnetic coating if the amplitude of the applied current oscillating at 50 Hz is close to the critical current. The ferromagnetic coating is seen to accumulate the magnetic field lines normally on its surfaces, while the field lines are parallel to the long axes of the wires, leading to more significant flux penetration in the coated regions. This facilitates a uniform low-loss current flow in the uncoated regions of the wires. In contrast, coating with a non-magnetic material gives rise to a considerably smaller current flow in the uncoated regions, whereas the low-loss flow is maintained in the coated regions. moreover, the current flows in opposite directions in the coated and uncoated regions, where the direction in each region is converse for the two materials.

关键词： second-generation superconductor two-layer cable ferromagnetic coating U profile alternating-current losses

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New Alkaloids from the Rhizomes of Goniothalamus Griffithii

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Chinese Chemical Letters 1998年第11期9卷 0-0,0-0页

作者： Zhang, YJ Kong, m Chen, ry Yu, DQ Chinese Acad med Sci Inst Mat Med Beijing 100050 Peoples R China Peking Union med Coll Beijing 100050 Peoples R China

Three new alkaloids, griffithdionc 1, griffiazanone A 2 and griffiazanone B 3 were isolated from the rhizomes of Goniothalamus griffithii Hook. F. el. Thoms. Their structures were elucidated by analysis the spectral data (IR, UV, mS, 1 H and 13C NmR, HmBC, NOE experiment).The absolute configuration of griffithazanone A 2 was determined by mosher's methods.

关键词： Goniothalamus griffithii phenanthrene lactam alkaloids griffithdione griffiazadioneA and griffiazadione B

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Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-merz Jorge Hernández-Campano Sergei A.Kirov Jesús m.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IryCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

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Thermomechanical Processing and Superplasticity of AZ91 magnesium Alloy

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Journal of materials Science & Technology 2004年第3期20卷 295-297页

作者： RongshiCHEN J.J.Blandin m.Suéry QudongWANG EnhouHAN StateKeyLabforCorrosionandProtection InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China InstitutNationalPolytechniquedeGrenoble(INPG)GéniePhysiqueetmécaniquedesmatériaux(GPm2) UMRCNRS5010ENSPGBP4638402Saint-Martind'HéresCedexFrance SchoolofmaterialsScience&Engineering NationalResearchCenterofLightAlloyNetFormingEngineeringShanghaiJiaoTongUniversityShanghai200030China

The effect of extrusion on grain refinement has been studied in the AZ91 cast ingots. It is found that grain sizesmaller than 10μm can be obtained by the extrusion processing. Vickers hardness measurements were also carriedout to evaluate the effect of these processes on the room temperature mechanical properties. The experimentalresults of high temperature tensile tests revealed that the stress was inversely proportional to the square of the grainsize and that the activation energy for superplastic flow was higher than that for grain boundary diffusion.

关键词： magnesium alloy Thermo-mechanical treatment Superplasticity mechanical properties

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Influence of extrusion temperature on microstructure and mechanical properties of mg-4Y-4Sm-0.5Zr alloy

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Transactions of Nonferrous metals Society of China 2010年第7期20卷 1311-1315页

作者：李大全王渠东丁文江 J.J.BLANDIN m.SUéry National Engineering Research Center for Nonferrous metals Composites General Research Institute for Nonferrous Metals National Engineering Research Center of Light Alloys Net Forming State Key Laboratory of Metal Matrix CompositesSchool of Materials Science and EngineeringShanghai Jiao Tong University Universitéde Grenoble Grenoble INPScience et Ingénieriedes Matériaux et Procédés(SIMAP) CNRS UMR 5266UJFBP 4638402 Saint-Martin d'Héres CedexFrance

The solution-treated mg-4Y-4Sm-0.5Zr alloy was extruded at temperatures from 325℃ to 500℃.Dynamic recrystallization(DRX) completely occurs when the alloy is extruded at 350℃and *** grains of the extruded alloy are obviously refined by the occurrence of *** average grain size of the extruded alloy increases with increasing the extrusion temperature,leading to a slight decrease of the ultimate tensile strength(UTS) and the yield strength(YS) .On the contrary,the UTS and YS of the extruded and aged alloy increase with increasing the extrusion *** of UTS of 400 mPa,YS larger than 300 mPa and elongation(EL) of 7%are achieved after extrusion at 400℃ and ageing at 200℃ for 16 *** grain refinement and precipitation are efficient strengthening mechanisms for the mg-4Y-4Sm-0.5Zr alloy.

关键词： mg-Y-Sm-Zr alloy extrusion heat treatment ageing mechanical properties

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Patterns of grassland invasions by trees: insights from demographic and genetic spatial analyses

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Journal of Plant Ecology 2015年第5期8卷 468-479页

作者： martin Dovčiak Richard Hrivnák Karol Ujházy Dušan Göm.ry State University of New York College of Environmental Science and Forestry(SUNY ESF)1 Forestry DriveSyracuseNY 13210USA Institute of Botany Slovak Academy of SciencesDúbravskácesta 9Bratislava 84523Slovakia Technical University in Zvolen Faculty of ForestryT.G.Masaryka 24Zvolen 96053Slovakia

Aims Woody invasions into grasslands have increased globally due to changing land use,climate and introduced woody species,but spatial processes generating and sustaining these invasions are not well *** gain insight into the patterns of spread of tree populations within grasslands,and to propose a full spatial analytical toolbox for studying native and non-native woody spe-cies spread when long-term data are not available,we tested if 50 years of grassland invasion in Western Carpathians by Norway spruce(Picea abies Karst.)proceeded by one of the two tradi-tionally competing hypotheses of species spread:(i)by frontier expansion,or(ii)by advanced groups established ahead of the population *** also tested whether the pattern of invasion changed over *** We analyzed the spatial demographic and genetic patterns of a Norway spruce population invading a Western Carpathian grass-land using ripley’s L(t)and genetic kinship coefficients(Fij).We mapped and genotyped spruce trees across the invasion front(from the invasion leading edge to fully colonized grassland near the source population)using three demographic classes(adults,juve-niles and seedlings)to approximate the temporal aspects of the *** studied how the spatial patterns of invasion by indi-vidual demographic classes and their genetic kinship varied among adjacent plots established at different distances from the source population(ranging from 0 to 160 m,in 40-m distance increments).Important Findings Juveniles were positively genetically related to adults on fine scales(m),suggesting that adults within the grassland acted as a seed source and accelerated early ***,adults did not act as nucleation centers for the formation of advanced juvenile ***,geneti-cally unrelated juveniles formed groups independently of *** groups were small and separate at the leading edge but they increased in size and graded into a continuous zone near the source popul

关键词： genetic spatial structure mountain meadows point pattern analysis population structure secondary succession

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mast cell stabilizing and antiallergic activity of Abrus precatorius in the management of asthma

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Asian Pacific Journal of Tropical medicine 2011年第1期4卷 46-49页

作者： DJ Taur ry Patil Department of Pharmacognosy S.V.P.M's College of PharmacyMalegaon(bk)Baramati-413115MaharashtraIndia Department of Pharmacognosy PDEA's S.U.College of Pharmaceutical Sciences and Research CenterKharadiPune-411014MaharashtraIndia

Objective:To investigate effects of ethanol extract of Abrus precatorius leaves（EAPL） on egg albumin induced mast cell degranulation in mice and passive cutaneous anaphylaxis in rats. methods:In present study ethanol extract of Abrus precatorius leaves（EAPL） at doses of 100,125, 150 mg/kg i.p were evaluated for preliminary phytochemical screening,acute toxicity studies and egg albumin induced mast cell degranulation in mice and passive cutaneous anaphylaxis in rats. Results:The results of present investigation showed that the LD50 of EAPL is more than 1300 mg/ ***（100-150 mg/kg,i.p.） significantly protect egg albumin induced degranulation of mast cell and inhibit area of leakage of dye in passive cutaneous *** studies observed presence of saponin,alkaloids,flavonoids,and ***:In conclusion EAPL possesses anti asthmatic potential.

关键词： Abrus precatorius Asthma mast cell Allergy

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Effects of aging on the microstructures and mechanical properties of extruded Am50+xCa magnesium alloys

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Rare metals 2006年第4期25卷 377-381页

作者： WANG Qudong PENG Jianguo Suéry michel Jean-Jacques Blandin National Engineering Research Centre of Light Alloys Net Forming School of Materials Science and Engineering Shanghai Jiaotong UniversityShanghai 200030 China Institute National Polytechnique de Grenoble （INPG） Génie Physique et Mécanique des Matériaux （GPM2） UMR CNRS 5010 ENSPG BP46 38402 Saint-Martin d＇Héres Cedex France

The effects of aging treatment on the microstructures and mechanical properties of extruded Am50 ＋ xCa alloys （x=0, 1, 2 wt.%） were studied. The results indicated the secondary phase mgl7Al12 precipitated from the saturated α-mg solid solution while Al2Ca changed slightly when the aging time was increased. The hardness of extruded Am50 ＋ xCa al- loys increased initially to its peak, and then dropped to reach its original hardness with the increase in aging time. With the increase in aging temperature, the hardness of the Am50 ＋ 2Ca ahoy decreased, whereas the hardness of Am50 and Am50 ＋ 1Ca alloys decreased in the initial stages of aging treatment and increased in the later stages of aging treatment. The tensile strengths of Am50 and Am50 ＋ 1Ca alloys increased after aging treatment for the precipitation of mg17Al12 phase, which increases the resistance against dislocation movement at the grain boundary; with increase in aging temperature, their tensile strengths increased. For Am50 ＋ 2Ca alloy, the tensile strength declined after aging at 150℃ and 175℃, while it increased slightly at 200℃. The ductility of Am50 ＋ xCa alloys （x = 0, 1, 2 wt.%） declined after aging treatment.

关键词： Am50 + xCa alloys aging extrusion mechanical properties

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Intraoperative complication rates in cataract surgery performed by resident trainees and staff surgeons in a tertiary eyecare center in Hungary

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International Journal of Ophthalmology(English edition) 2022年第4期15卷 586-590页

作者： márton magyar Gábor László Sándor László Ujváry Zoltán Zsolt Nagy Gábor Tóth Department of Ophthalmology Semmelweis UniversityBudapest 1085Hungary

AIm: To compare the incidence of intraoperative complications during prim.ry phacoemulsification(phaco) surgery between resident surgeons(residents) and staff surgeons(specialists) and to objectively determine the difficulty of stages in phaco surgery. mETHODS: This retrospective study included cases of phaco cataract surgery performed between January and December 2019. There were no exclusion criteria. For each patient, demographics, clinical history, case complexity, type of surgeon, and operative details were reviewed. Prim.ry outcomes included intraoperative complication rates and the objective measure of difficulty in the steps of the surgery performed by residents and ***: A total of 3272 cases were included;7.4%(n=241) of cases were performed by residents. The overall complication rate was 5.4%(n=177). The intraoperative complication rate was significantly higher(Pmost frequent complications were posterior capsule tear(n=85, 2.6%), anterior capsule tear(n=50, 1.53%), zonular fiber loss(n=45, 1.38%), and dropped nucleus(n=15, 0.46%). Objectively, the most difficult steps during surgery were phaco in 66(60.0%), capsulorhexis in 21(19.1%), irrigation/aspiration in 13(11.8%), hydrodissection in 9(8.2%), and intraocular lens(IOL) implantation in 1(0.9%) case. CONCLUSION: Intraoperative complication rates are higher in residents than in specialists. The order of objective difficulty in phaco surgery steps is in line with the subjective findings of other surveys, revealing that the most challenging parts of phaco surgery are phaco and capsulorhexis.

关键词： cataract intraoperative complications resident phacoemulsification staff surgeon

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Alcohol metabolites and lipopolysaccharide: Roles in the development and/or progression of alcoholic liver disease

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World Journal of Gastroenterology 2009年第10期15卷 1209-1218页

作者： Courtney S Schaffert michael J Duryee Carlos D Hunter Bartlett C Hamilton 3rd Amy L DeVeney m.ry m.huerter Lynell W Klassen Geoffrey m Thiele Department of Internal medicine University of Nebraska Medical Center 986350 Nebraska Medical Center Omaha NE 68198-6350 United States Veterans Administration Alcohol Research Center Omaha Veterans Administration Medical Center 4101 Woolworth Avenue Omaha NE 68105 United States Department of Pathology and microbiology University of Nebraska Medical Center 986495 Nebraska Medical Center Omaha NE 68198-6495 United States

The onset of alcoholic liver disease (ALD) is initiated by different cell types in the liver and a number of different factors including: products derived from ethanol-induced inflammation, ethanol metabolites, and the indirect reactions from those metabolites. Ethanol oxidation results in the production of metabolites that have been shown to bind and form protein adducts, and to increase inflammatory, fibrotic and cirrhotic responses. Lipopolysaccharide (LPS) has many deleterious effects and plays a significant role in a number of disease processes by increasing inflammatory cytokine release. In ALD, LPS is thought to be derived from a breakdown in the intestinal wall enabling LPS from resident gut bacterial cell walls to leak into the blood stream. The ability of adducts and LPS to independently stimulate the various cells of the liver provides for a two-hit mechanism by which various biological responses are induced and result in liver injury. Therefore, the purpose of this article is to evaluate the effects of a two-hit combination of ethanol metabolites and LPS on the cells of the liver to increase inflamma-tion and fi brosis, and play a role in the development and/or progression of ALD.

关键词： Alcoholic liver disease Inflammation Fibrosis Sinusoidal liver endothelial cells Kupffer cells Hepatocyte Stellate cells Precision cut liver slices

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