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Modern treatment of gastric gastrointestinal stromal tumors

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World Journal of Gastroenterology 2012年第46期18卷 6720-6728页

作者： kevin K Roggin Mitchell C Posner Department of Surgery Pritzker School of Medicine University of Chicago

Gastrointestinal stromal tumors (GIST) are rare mesenchymal smooth muscle sarcomas that can arise anywhere within the gastrointestinal tract. Sporadic mutations within the tyrosine kinase receptors of the interstitial cells of Cajal have been identified as the key molecular step in GIST carcinogenesis. Although many patients are asymptomatic, the most common associated symptoms include: abdominal pain, dyspepsia, gastric outlet obstruction, and anorexia. Rarely, GIST can perforate causing life-threatening hemoperitoneum. Most are ultimately diagnosed on cross-sectional imaging studies (i.e., computed tomography and/or magnetic resonance imaging in combination with upper endoscopy. Endoscopic ultrasonographic localization of these tumors within the smooth muscle layer and acquisition of neoplastic spindle cells harboring mutations in the c-KIT gene is pathognomonic. Curative treatment requires a complete gross resection of the tumor. Both open and minimally invasive operations have been shown to reduce recurrence rates and improve long-term survival. While there is considerable debate over whether GIST can be benign neoplasms, we believe that all GIST have malignant potential, but vary in their propensity to recur after resection and metastasize to distant organ sites. Prognostic factors include location, size (i.e., > 5 cm), grade (> 5-10 mitoses per 50 high power fields and specific mutational events that are still being defined. Adjuvant therapy with tyrosine kinase inhibitors, such as imatinib mesylate, has been shown to reduce the risk of recurrence after one year of therapy. Treatment of locally-advanced or borderline resectable gastric GIST with neoadjuvant imatinib has been shown to induce regression in a minority of patients and stabilization in the majority of cases. This treatment strategy potentially reduces the need for more extensive surgical resections and increases the number of patients eligible for curative therapy. The modern surgical treatment of

关键词： Gastrointestinal stromal tumors Laparoscopic resections of gastrointestinal stromal tumors Imatinib mesylate Gastrectomy

Managing Climate Change Risk in China's Agricultural Sector: The Potential for an Integrated Risk Management Framework

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Journal of Integrative Agriculture 2014年第7期13卷 1418-1431页

作者： kevin Z.Chen Claire Hsu International Food Policy Research Institute-Beijing Office

Climate change poses a serious threat to the future food security of China, which is among the most disaster-prone countries in the world. This paper discusses the implications of climate change for China＇s agricultural sector. Its main objectives are to identify the agricultural risks associated with climate change, to introduce a conceptual framework for agricultural climate risk management and to enumerate key adaptation strategies, challenges, and recommendations.

关键词： climate change food security risk management agricultural development

Extracting inter-area oscillation modes using local measurements and data-driven stochastic subspace technique

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Journal of Modern Power Systems and Clean Energy 2017年第5期5卷 704-712页

作者： Deyou YANG Guowei CAI kevin CHAN School of Electrical Engineering Northeast Dianli UniversityJilinChina Department of Electrical Engineering The Hong Kong Polytechnic UniversityKowloonHong KongSARChina

In this paper, a data-driven stochastic subspace identification(SSI-DATA) technique is proposed as an advanced stochastic system identification(SSI) to extract the inter-area oscillation modes of a power system from wide-area measurements. For accurate and robust extraction of the modes’ parameters(frequency, damping and mode shape), SSI has already been verified as an effective identification algorithm for output-only modal *** new feature of the proposed SSI-DATA applied to inter-area oscillation modal identification lies in its ability to select the eigenvalue automatically. The effectiveness of the proposed scheme has been fully studied and verified,first using transient stability data generated from the IEEE16-generator 5-area test system, and then using recorded data from an actual event using a Chinese wide-area measurement system(WAMS) in 2004. The results from the simulated and recorded measurements have validated the reliability and applicability of the SSI-DATA technique in power system low frequency oscillation analysis.

关键词： Data-driven stochastic subspace identification(SSI-DATA) Power system inter-area oscillation Widearea measurement systems(WAMS) Modal analysis

The Complex Magnetism in the Breathing Pyrochlore LiIn(Cr_(1-x)Rh_x)_4O_8

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Chinese Physics Letters 2016年第12期33卷 129-132页

作者：王冬逸谭程 kevin Huang 殳蕾 State Key Laboratory of Surface Physics Department of PhysicsFudan University Collaborative Innovation Center of Advanced Microstructures

We perform a detailed investigation of the new ＇breathing＇ pyrochlore compound LiInCr4O8 through Rh substi- tution with measurements of magnetic susceptibility, specific heat, and x-ray powder diffraction. The antiferro- magnetic phase of LiInCr4O8 is found to be slowly suppressed with increasing Rh, up to the critical concentration of x = 0.1 where the antiferromagnetic phase is still observed with the peak in specific heat Tp = 12.5 K, slightly lower than Tp =14.3 K for the x = 0 compound. From tile measurements of magnetization we also uncover evidence that substitution increases the amount of frustration. Comparisons are made with the LiGayIn1-yCr4O8 system as well as other frustrated pyrochlore-related materials and comparable amounts of frustration are found. The results of this work show that the engineered breathing pyrochlores present an important method to further understand the complex magnetism in frustrated systems.

关键词： Rh is for in of x)Rh_x The Complex Magnetism in the Breathing Pyrochlore LiIn Cr

STRONG PREDICTOR-CORRECTOR APPROXIMATION FOR STOCHASTIC DELAY DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2015年第6期33卷 587-605页

作者： Yuanling Niu Chengjian Zhang kevin Burrage School of Mathematics and Statistics Central South University Changsha 410075 China School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan 430074 China School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan 430074 China Department of Computer Science Oxford University Wolfson Building Parks Road Oxford OX1 3QD UK School of Mathematical Sciences Queensland University of Technology Brisbane Australia

This paper presents a strong predictor-corrector method for the numerical solution of stochastic delay differential equations （SDDEs） of ItS-type. The method is proved to be mean-square convergent of order min{1/2,p} under the Lipschitz condition and the linear growth condition, where p is the exponent of HSlder condition of the initial function. Stability criteria for this type of method are derived. It is shown that for certain choices of the flexible parameter p the derived method can have a better stability property than more commonly used numerical methods. That is, for some p, the asymptotic MS-stability bound of the method will be much larger than that of the Euler-Maruyama method. Numerical results are reported confirming convergence properties and comparing stability properties of methods with different parameters p. Finally, the vectorised simulation is discussed and it is shown that this implementation is much more efficient.

关键词： Strong predictor-corrector approximation Stochastic delay differential equa- tions Convergence Mean-square stability Numerical experiments Vectorised simulation.

Testosterone and cardiovascular disease in men

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Asian Journal of Andrology 2012年第3期14卷 428-435,I0007页

作者： Paul D Morris kevin S Channer Sheffield Teaching Hospital NHS Trust Sheffield S10 2JF UK

Despite regional variations in the prevalence of coronary artery disease （CAD）, men are consistently more at risk of developing and dying from CAD than women, and the gender-specific effects of sex hormones are implicated in this inequality. This ＇Perspectives＇ article reviews the current evidence regarding the cardiovascular effects of testosterone in men including an examination of the age-related decline in testosterone, the relationship between testosterone levels and coronary disease, coronary risk factors and mortality. We also review the vaso-active effects of testosterone, and discuss how these have been used in men with heart failure and angina. We discuss the ＇cause＇ versus ＇effect＇ controversy, regarding low testosterone levels in men with coronary heart disease, as well as concerns over the use of testosterone replacement therapy in middle aged and elderly men. The article concludes with a discussion regarding the future direction for work in this interesting area, including the relative merits of screening for, and treating hypogonadism with testosterone replacement therapy in men with heart disease.

关键词： atherosclerosis chronic heart failure ischaemic heart disease replacement therapy testosterone

Resident and migratory adipose immune cells control systemic metabolism and thermogenesis

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Cellular & Molecular Immunology 2022年第3期19卷 421-431页

作者： kevin Man Axel Kallies Ajithkumar Vasanthakumar Peter Doherty Institute for Infection and Immunity MelbourneVICAustralia Department of Microbiology and Immunology University of MelbourneMelbourneVICAustralia Olivia Newton-John Cancer Research Institute MelbourneVICAustralia

Glucose is a vital source of energy for all *** balance between glucose uptake,metabolism and storage determines the energy status of an individual,and perturbations in this balance can lead to metabolic *** maintenance of organismal glucose metabolism is a complex process that involves multiple tissues,including adipose tissue,which is an endocrine and energy storage organ that is critical for the regulation of systemic *** tissue consists of an array of different cell types,including specialized adipocytes and stromal and endothelial *** addition,adipose tissue harbors a wide range of immune cells that play vital roles in adipose tissue homeostasis and *** cells contribute to the regulation of systemic metabolism by modulating the inflammatory tone of adipose tissue,which is directly linked to insulin sensitivity and ***,these cells affect the control of *** lean adipose tissue is rich in type 2 and anti-inflammatory cytokines such as IL-10,obesity tips the balance in favor of a proinflammatory milieu,leading to the development of insulin resistance and the dysregulation of systemic ***,anti-inflammatory immune cells,including regulatory T cells and innate lymphocytes,protect against insulin resistance and have the characteristics of tissue-resident cells,while proinflammatory immune cells are recruited from the circulation to obese adipose ***,we review the key findings that have shaped our understanding of how immune cells regulate adipose tissue homeostasis to control organismal metabolism.

关键词： adipose tissue immune cells metabolism

Dopaminergic modulation of synaptic plasticity in rat prefrontal neurons

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Neuroscience Bulletin 2015年第2期31卷 183-190页

作者： Satoru Otani Jing Bai kevin Blot Center for Medical Education Faculty of Health Sciences Ryotokuji University Chinese Medicine Research Laboratory Juntendo University Medical School Pathophysiology Department University of Paris 6

The prefrontal cortex （PFC） is thought to store the traces for a type of long-term memory - the memory that determines the temporal structure of behavior often termed a ＂rule＂ or ＂strategy＂. Long-term synaptic plasticity might serve as an underlying cellular mechanism for this type of memory. We therefore studied the induction of synaptic plasticity in rat PFC neurons, maintained in vitro, with special emphasis on the functionally important neuromodulator dopamine. First, the induction of long-term potentiation （LTP） was facilitated in the presence of tonic/background dopamine in the bath, and the dose-dependency of this background dopamine followed an ＂inverted-U＂ function, where too high or too low dopamine levels could not facilitate LTP. Second, the induction of long-term depression （LTD） by low-frequency stimuli appeared to be independent of background dopamine, but required endogenous, phasically-released dopamine during the stimuli. Blockade of dopamine receptors during the stimuli and exaggeration of the effect of this endogenouslyreleased dopamine by inhibition of dopamine transporter activity both blocked LTD. Thus, LTD induction also followed an inverted-U function in its dopamine-dependency. We conclude that PFC synaptic plasticity is powerfully modulated by dopamine through inverted-U-shaped dose-dependency.

关键词： prefrontal cortex synaptic plasticity long-term memory

CRACK PROPAGATION IN STRUCTURES SUBJECTED TO PERIODIC EXCITATION

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Acta Mechanica Solida Sinica 2007年第3期20卷 236-246页

作者： Zhang Yin Murphy kevin D. State Key Laboratory of Nonlinear Mechanics （LNM） Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Department of Mechanical Engineering University of Connecticut CT 06269-3139 USA

In the present paper, asimple mechanical modelis developed to predict thedynamic response of a cracked structure subjected to periodic excitation, which has been used to identify the physical mechanisms in leading the growth or arrest of cracking. The structure under consideration consists of a beam with a crack along the axis, and thus, the crack may open in Mode I and in the axial direction propagate when the beam vibrates. In this paper, the system is modeled as a cantilever beam lying on a partial elastic foundation, where the portion of the beam on the foundation represents the intact portion of the beam. Modal analysis is employed to obtain a closed form solution for the structural response. Crack propagation is studied by allowing the elastic foundation to shorten （mimicking crack growth） if a displacement criterion, based on the material toughness, is met. As the crack propagates, the structural model is updated using the new foundation length and the response continues. From this work, two mechanisms for crack arrest are identified. It is also shown that the crack propagation is strongly influenced by the transient response of the structure.

关键词： crack propagation/arrest elastic foundation modal analysis vibration natural frequency