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核物理动态 1992年第2期9卷 29-34,15页

作者：丁训良 G.Schatz R.Fink G.Krausch B.Luckscheiter R.Platzer j.voigt U.W■hrmann 北京师范大学低能核物理研究所北京100875 Fakultt für Physik Universitt KonstanzD-7750 KonstanzFRG

扰动角关联方法,作为一种超精细相互作用技术,具有高的微观灵敏度,可研究局部范围的表面性质.其在表面研究中的应用已涉及表面现象的各个方面,揭示了一系列感兴趣的现象.通过测量作用在探核上的电场梯度,可辨认探针在表面的不同位置,研... 详细信息

扰动角关联方法,作为一种超精细相互作用技术,具有高的微观灵敏度,可研究局部范围的表面性质.其在表面研究中的应用已涉及表面现象的各个方面,揭示了一系列感兴趣的现象.通过测量作用在探核上的电场梯度,可辨认探针在表面的不同位置,研究杂质与探针相互作用及扩散过程.利用扰动角关联技术已经观察到探核从表面吸附位置经与台阶有关的位置到达表面最上层晶格点阵替位的微扩散过程.本文综述扰动角关联在表面物理研究中的应用以及Ni 单晶表面和超薄Ni 膜磁性质研究的最新结果.

关键词：扰动角关联表面物理微扩散过程

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胰腺癌

德国医学 2001年第3期18卷 166-168页

作者： E.T.Sternheim j.voigt W.Kaspar W.G.Dippold 胡广原 Abteilung lnnere Medizin St.-Vincenz- und Elisabeth-Hospital 华中科技大学同济医学院附属同济医院

胰腺癌是胰腺导管上皮恶变形成，为最常见的恶性肿瘤。由于组织学上的多样性，根据WHO分类法将其分为5类：导管癌、胰泡细胞癌、混合细胞癌、未确定细胞型及未分类细胞型胰腺癌。其中导管癌占75%～92%。胰腺癌根据TNM分期法进行分期。... 详细信息

胰腺癌是胰腺导管上皮恶变形成，为最常见的恶性肿瘤。由于组织学上的多样性，根据WHO分类法将其分为5类：导管癌、胰泡细胞癌、混合细胞癌、未确定细胞型及未分类细胞型胰腺癌。其中导管癌占75%～92%。胰腺癌根据TNM分期法进行分期。病因学及危险因素胰腺癌的发生中吸咽影响最大。芳香胺类(如吸烟或工作环境中所接触)是胰腺癌危险因子。水果、蔬菜和维生素丰富的食物有保护作用，因为它们可抑制胺类的致突变作用。其他危险因素有：肥胖、酗酒、慢性胰腺炎及常染色体显性遗传性胰腺炎。一直以来人们认为糖尿病与胰腺癌之间有一定的关系，若新出现糖尿病代谢障碍时应怀疑胰腺癌。最新一项研究表明，胰腺癌的一些危险因素如尼古丁、肥胖与Ⅰ型、Ⅱ型糖尿病与胰腺癌发病有较微弱的联系。病因学基础胰腺癌常有多种基因发生突变，如原癌基因K-ras激活及4种抑癌基因p53、DPC4、CDKN2、BRCA-2失活。

关键词：胰腺癌病理学流行病学诊断治疗

日粮营养水平对青年山羊瘤胃上皮发育和功能调节的内分泌机制

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日粮营养水平对青年山羊瘤胃上皮发育和功能调节的内分泌机制

Error field penetration in j-TEXT tokamak based on two-fluid drift-MHD model

动物生理生化学分会第八次学术会议暨全国反刍动物营养生理...

作者：沈赞明 H-M Seyfert B.Lhrke F.Schneider R.■itnan S.Kuhla H.M.Hammon j.W.Blum H.Martens H.Hagemeister j.voigt 南京农业大学 FBN Dummerstorf Germany Research Institute of Animal Production Nitra Slovakia University of Berne Switzerland Free University Berlin Germany

24只青年公山羊随机分为2组(n=12),分别饲喂高能量和高蛋白(HG,1000 kj·kg(-0.75)·(d-1)],2500mg·kg(-0.75)·(d-1)])或低能量和有蛋白(LG,500 kj·kg(-0.75)·(d-1)] and 1150 mg·kg(-0.75)·(d-1)])日粮,试验期42天。试验前一天和试验期内隔周分别经颈静脉采血,试验结束屠宰山羊,取瘤胃上皮和瘤胃液分别测定瘤胃挥发性脂肪酸浓度(气相色谱法)、瘤胃上皮表面积(computer-operated Image C picture analysissystem)、瘤胃上皮对比Na的运输(ussing-chamber技术)、血浆IGF-1的浓度(RIA)、瘤胃上皮IGF-1受体(IGF-1R,配体结合实验)数量、IGF-1和IGF-1R的mRNA(Real-time PCR),以及IGF-1对体

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j-TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

Storing Freshwater Versus Storing Electricity in Power Systems with High Freshwater Electric Demand

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journal of Modern Power Systems and Clean Energy 2024年第2期12卷 323-333页

作者： Mubarak j.Al-Mubarak Antonio j.Conejo Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOHUSA Department of Electrical Engineering Kuwait UniversityP.O.Box 5969Safat 13060Kuwait Department of Integrated Systems Engineering and the Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOH 43210USA IEEE

We consider a power system whose electric demand pertaining to freshwater production is high(high freshwater electric demand),as in the Middle East,and investigate the tradeoff of storing freshwater in tanks versus storing electricity in batteries at the day-ahead operation *** storing freshwater and storing electricity increase the actual electric demand at valley hours and decrease it at peak hours,which is generally beneficial in term of cost and ***,to what extent?We analyze this question considering three power systems with different generation-mix configurations,i.e.,a thermal-dominated mix,a renewable-dominated one,and a fully renewable *** generation-mix configurations are inspired by how power systems may evolve in different countries in the Middle *** production uncertainty is compactly modeled using chance *** draw conclusions on how both storage facilities(freshwater and electricity)complement each other to render an optimal operation of the power system.

关键词： Power system operation freshwater production and transportation coordination day-ahead scheduling

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： Robert j.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management

Decoding the genetic program of micronucleus formation: linking chromosomal instability to human disease

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2840-2842页

作者： jörg Fahrer Division of Food Chemistry and Toxicology Department of ChemistryRPTU Kaiserslautern-Landau67663 KaiserslauternGermany

A recent study by Adams and colleagues published in Nature unveiled more than one hundred genes that are involved in micronucleus formation,1 which is a biomarker for genomic instability and associated with aging,cancer,and other disorders.2 As an outstanding achievement,the authors identified DSCC1(DNA Replication And Sister Chromatid Cohesion 1)as a critical gene protecting against early developmental defects,genomic instability,reduced proliferative capacity,cohesinopathy-related phenotypes,and tumor development in vivo.

关键词： chromosomal linking Replication