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Tunable electron and phonon properties of folded single-layer molybdenum disulfide

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Nano research 2018年第3期11卷 1541-1553页

作者： Jie Peng Peter W. Chung Madan Dubey Raju R. Namburu Department of Mechanical Engineering University of Maryland College Park MD 20742 USA sensors & Electron Devices Directorate U.S. Army Research Laboratory Adelphi MD 20783 USA Computational & Information sciences Directorate U.S. Army Research Laboratory Aberdeen Proving Ground MD 21005 USA

A unique feature of transition metal dichalcogenides is their single-layer form, which enables folding. Although folding has been found to significantly affect the photoluminescence spectrum and some in-plane properties, only limited insight has been gained on how to modulate those properties. In this report, we examine the structure of folds of a single sheet of Mos2 and the dependence of the ground-s tate electronic and phonon transport properties on the wrapping length. As the folded structure is effectively a bilayer that terminates in a loop, the wrapping length modulates the relative size of the bilayer region to the closed loop along the edge. A combination of computational methods, including approaches based on variational mechanics, classical potentials, and density functional theory, are employed. Highly accurate calculations of the reference folded structure are first carried out to show that the folded structure is largely insensitive to the wrapping length. The folded structures are su.s.quently used to estimate the electronic band gap, which is found to vary significantly as a function of the wrapping length, and converges from below to the limit value corresponding to an infinite bilayer. The gap valu.s.range from 0.43 to 1.09 eV, with a crossover to an indirect gap, which suggests that the transitions must be lattice-assisted, similar to the transitions in the bilayer and bulk forms. However, the phonons, while affected by the formation of the folded structure, are insensitive to the wrapping length. In fact, the overall thermal transport behavior along the folding axis is unchanged. The possibility of modulating the gap value while keeping the thermal properties unchanged opens up new exciting avenu.s.for further applications of this emerging material.

关键词： molybdenum disulfide folded structure electronic band structure thermal conductivity phonon

Discrete-time dynamic graphical games:model-free reinforcement learning solution

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Control Theory and Technology 2015年第1期13卷 55-69页

作者： Mohammed I.ABOuHEAF Frank L.LEWIs Magdi s.MAHMOuD Dariusz G.MIKu.s.I systems Engineering Department King Fahd University of Petroleum & Mineral uTA research institute University of Texas at ArlingtonFort Worth Texas U.S.A. state Key Laboratory of synthetical Automation for Process Industries Northeastern University Ground Vehicle Robotics (GVR) U.S. Army TARDEC Warren MI U.S.A.

This paper introduces a model-free reinforcement learning technique that is used to solve a class of dynamic games known as dynamic graphical games. The graphical game results from to make all the agents synchronize to the state of a command multi-agent dynamical systems, where pinning control is used generator or a leader agent. Novel coupled Bellman equations and Hamiltonian functions are developed for the dynamic graphical games. The Hamiltonian mechanics are used to derive the necessary conditions for optimality. The solution for the dynamic graphical game is given in terms of the solution to a set of coupled Hamilton-Jacobi-Bellman equations developed herein. Nash equilibrium solution for the graphical game is given in terms of the solution to the underlying coupled Hamilton-Jacobi-Bellman equations. An online model-free policy iteration algorithm is developed to learn the Nash solution for the dynamic graphical game. This algorithm does not require any knowledge of the agents＇ dynamics. A proof of convergence for this multi-agent learning algorithm is given under mild assumption about the inter-connectivity properties of the graph. A gradient descent technique with critic network structures is used to implement the policy iteration algorithm to solve the graphical game online in real-time.

关键词： Dynamic graphical games Nash equilibrium discrete mechanics optimal control model-free reinforcementlearning policy iteration

Proteostasis failure:at the intersection between aging and Alzheimer's disease

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Neural Regeneration research 2025年第11期20卷 3221-3222页

作者： Natalia Poblete Claudio Hetz Center for Geroscience Brain Health and MetabolismSantiagoChile Biomedical Neuroscience institute Faculty of MedicineUniversity of ChileSantiagoChile Program of Cellular and Molecular Biology Institute of Biomedical SciencesFaculty of MedicineUniversity of ChileSantiagoChile Buck institute for research on Aging NovatoCAUSA

Lifestyle and demographics of the world's population are causing serious health problems impacting the brain,increasing the incidence of Alzheimer's disease(AD)and other types of *** we have gained important insights into the pathogenic mechanisms of AD,only palliative care is available to *** is characterized by the abnormal deposition of protein aggregates in the brain formed by amyloid β and hyper-phosphorylated,Tau in addition to neuroinflammation.

关键词： Alzheimer amyloid stasis

Hydration Assessment of Athletes

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中国运动医学杂志 2006年第2期25卷 238-244页

作者： samuel N.Cheuvront Michael N.sawka Thermal and Mountain Medicine Division u. s . army research institute of Environmental Medicine Natick USA

KEY POINTs Although there is no scientific consensus for 1 ） how best to assess the hydration status of athletes, 2）what criteria to use as acceptable outcome measurements, or 3） the best time to apply practical assessment methods, there are methods that can be used toprovide athletes with useful feedback about their hydration status.

关键词：运动员评价水合作用运动医学

Impact of prehospital medical evacuation (MEDEVAC) transport time on combat mortality in patients with noncompressible torso injury and traumatic amputations: a retrospective study

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Military Medical research 2019年第1期6卷 23-30页

作者： Joseph K.Maddry Crystal A.Perez Alejandra G.Mora Jill D.Lear shelia C.savell Vikhyat s.Bebarta us Air Force En route Care research Center 59th MDW/sT Chief Scientist's Office –US Army Institute of Surgical research JBSA Ft.Sam Houston Department of Emergency Medicine San Antonio Military Medical CenterJBSA Ft. Sam Houston us Air Force En route Care research Center 59th MDW/sT Chief Scientist's Office –US Army Institute of Surgical researchJBSA Ft.Sam Houston Department of Emergency Medicine University of Colorado School of Medicine

Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. studies have shown that long transport times are associated with increased morbidity and mortality. Limited data exist on the influence of transport time on patient outcomes with specific injury types. The objective of this study was to determine the impact of the duration of time from the initial requ.s. for medical evacuation to arrival at a medical treatment facility on morbidity and mortality in casualties with traumatic extremity amputation and noncompressible torso injury(NCTI).Methods: We completed a retrospective review of MEDEVAC patient care records for united states military personnel who sustained traumatic amputations and NCTI during Operation Enduring Freedom between January 2011 and March 2014. We grouped patients as traumatic amputation and NCTI(AMP+NCTI), traumatic amputation only(AMP),and neither AMP nor NCTI(Non-AMP/NCTI). Analysis was performed using chi-squared tests, Fisher's exact tests,Cochran-Armitage Trend tests, shapiro-Wilks tests, Wilcoxon and Kruskal-Wallis techniqu.s.and Cox proportional hazards regression ***: We reviewed 1267 records, of which 669 had an injury severity score(Iss) of 10 or greater and were included in the analysis. In the study population, 15.5% sustained only amputation injuries(n=104, AMP only), 10.8% sustained amputation and NCTI(n=72, AMP+NCTI), and 73.7% did not sustain either an amputation or an NCTI(n=493,Non-AMP/NCTI). AMP+NCTI had the highest mortality(16.7%) with transport time greater than 60 min. While the AMP+NCTI group had decreasing survival with longer transport times, AMP and Non-AMP/NCTI did not exhibit the same ***: A decreased transport time from the point of injury to a medical treatment facility was associated with decreased mortality in patients who suffered a combination of amputation injury and NCTI. No significant association between transport time

关键词： Transport time Non-compressible torso injury Traumatic amputation Combat

Feasibility of terahertz imaging for discrimination of human hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2019年第2期11卷 153-160页

作者： Feng Duan Yu-Ye Wang De-Gang Xu Jia shi Lin-Yu Chen Li Cui Yan-Hua Bai Yong Xu Jing Yuan Chao Chang Department of Interventional Radiology the General Hospital of Chinese People’s Liberation Army institute of Laser and Optoelectronics School of Precision Instruments and Optoelectronic Engineering Key Laboratory of Optoelectronic Information Science and Technology (Ministry of Education) Tianjin University Department of Hepatobiliary and Pancreatic surgical Oncology the General Hospital of Chinese People’s Liberation army Department of Pathology the General Hospital of Chinese People’s Liberation Army Advanced Interdisciplinary Technology research Center National Innovation Institute of Defense Technology

BACKGROuND Hepatocellular carcinoma(HCC) is one of the most common malignant tumors worldwide, and novel methods for early/rapid diagnosis of HCC are ***(THz) spectroscopy is considered to have the potential to distingu.s. between normal liver tissue and HCC tissue; however, there are few reports on *** conduct this observational study to explore the feasibility of THz imaging for the diagnosis of *** To evaluate the feasibility of THz for discriminating between HCC and normal liver tissu.s.using fresh tissue specimens obtained from HCC patients who had undergone *** Normal liver tissue and HCC tissue were cryosectioned into 50 μm-thick slicesand placed on cover glass. Two adjacent tissue sections were separated subjected to histopathological examination by hematoxylin and eosin staining or THz transmission examination, and THz images were compared with pathologically mapped images. We determined the typical tumor and normal liver tissue regions by pathological examination; the corresponding areas of adjacent sections were examined by THz *** The transmission rate of HCC tissue was 0.15-0.25, and the transmission rate of typical HCC tissue was about 0.2. THz transmittance in normal liver tissue is slightly higher than 0.4, but there were many influencing factors, including the degree of liver cirrhosis, fat components, ice crystals in frozen sections, and *** In conclusion, this study shows that THz imaging can detect HCC tissue. Further research will yield more detailed data of the THz transmission rates of HCC tissue with different degrees of differentiation.

关键词： Terahertz imaging Hepatocellular carcinoma Hematoxylin and eosin staining Terahertz transmittance Liver pathology

A tool for estimating antiretroviral medication coverage for HIV-infected women during pregnancy(PMTCT-ACT)

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Global Health research and Policy 2019年第1期4卷 87-94页

作者： Bruce A.Larson Nafisa Halim Isaac Tsikhu.s. Margaret Bii Peter Coakley Peter C.Rockers Department of Global Health Boston University School of Public Health801 Massachusetts AvenueBostonMA 02118USA Kenya Medical research institute U.S.Army Medical Research DirectorateAfricaKenya u.s.Military HIV research Program Walter Reed Army Institute of ResearchSilver SpringMDUSA Henry Jackson Foundation MRI KerichoKenya

Background:In the typical prevention of mother to child transmission(PMTCT)of HIV cascade of care discu.s.on or analysis,the period of analysis begins at the first visit for antenatal care(ANC)for that *** starting point is problematic for two reasons:(1)a large number of HIV-infected women are already on life-long antiretroviral therapy(ART)when presenting for ANC;and(2)women present to ANC at different gestational *** PMTCT ART Coverage Tool(PMTCT-ACT),which estimates the proportion of days covered(PDC)with ART,was developed to address each of these ***:PDC is a preferred method to measure adherence to chronic medications,such as *** evaluating the PMTCT cascade of care,as indicated by PDC with ART over various time periods,a“starting point”based on a specific day before delivery must be defined that applies to all women(treatment experienced or naïve at the first ANC visit at any gestational age).using the example of 168 days prior to delivery(24 weeks),PMTCT-ACT measures PDC with ART during that ***-ACT is provided as a sTATA *** an example dataset for two women(ID1 is treatment experienced;ID2 is treatment naïve),the details of each major portion of the tool(Parts 1-5)are ***-ACT along with the intermediate datasets created during the analysis are provided as supplemental ***:Evaluating the PMTCT cascade of care requires a standard definition of the follow-up period during pregnancy that applies to all HIV-infected pregnant women and a standard measure of ***-ACT is a new tool that fits this ***-ACT can also be easily adjusted to evaluate other ante-and post-natal periods(e.g.,final 4 weeks,final 8 weeks,complete pregnancy period,initial 24 weeks postpartum,time periods consistent with infant HIV testing guidelines).

关键词： HIV Pregnancy Prevention of mother-to-child transmission Cascade of care Pill count Coverage Proportion of days covered

Protective effects of lidocaine injected into the hepatoduodenal ligament on warm ischemia-reperfusion injury to the rat liver

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Chinese Medical Journal 2004年第2期17卷 275-279页

作者：陈明易李崇辉黄志强刘巨超周宁新黄晓强王燕生 Department of Hepatobiliary surgery General Surgical Research Institute Chinese People' s Liberation Army General Hospital Beijing 100853 China

Background Ischemia-reperfusion (IR) injury to the liver is still a critical and daunting problem in the field of hepatobiliary surgery. Ischemic preconditioning (IP) of the liver serves as an effective approach against IR injury. This study was to develop a novel procedure that could mimic IP, but might be more feasible than IP during surgery.Methods Eighty-two sD rats were randomly divided into 5 grou.s. L group (n = 21 ): 0. 4% lidocaine (10 mg/kg) was injected into the hepatoduodenal ligament 10 minutes before a 40-minute hepatic IR. IP group (n =16): a 5-minute ischemia was followed by a 10-minute reperfusion prior to a 40-minute hepatic IR. ILR group (n =15): after a 40-minute ischemia of the liver, 0.4% lidocaine (10 mg/kg) was injected into the hepatoduodenal ligament 10 minutes prior to a 40-minute reperfusion of the liver. IR group (n =15): the liver of the rat was subjected to a 40-minute IR. Control group (n = 15): 0. 9% sodium chloride was injected into the hepatoduodenal ligament without other treatments. The levels of plasma alanine transaminase (ALT) and aspartate transaminase (AsT) were determined for each group after treatment.Results The mean concentrations of ALT and AsT were (379. 80 ±141. 69) u/L and (606. 05 ± 220. 26) u/L for the L group, (334. 64 ±141. 94) u/L and (625. 68 ±267. 06) u/L for the IP group, (523. 36 ±170. 35) u/L and (765. 47 ±238. 45) u/L for the ILP group, (524. 29 ±163. 59) u/L and (764. 63 ±246. 79) u/L for the IR group, and (150. 90 ±27. 05) u/L and (298. 15 ±47. 68) u/L for the control group (standard error of the mean).Conclusion A significant decrease in ALT and AsT levels was observed in the L and IP grou.s.when compared to the ILR and IR grou.s.(Put no significant difference in ALT and AsT levels was observed in the L group when compared to the IP group (P>0. 05). These results suggest that pretreatment with lidocaine injected into the hepatoduodenal ligament prior to IR provide

关键词： liver ischemic preconditioning ischemia-reperfusion injury lidocaine inneruation

sequential changes of body composition in patients with enterocutaneous fistula during the 10 days after admission

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World Journal of Gastroenterology 2002年第6期8卷 1149-1152页

作者： Xin-Bo Wang Jian-An Ren Jie-shou Li,Clinical school of Medical College,Nanjing university,research institute of General surgery,Nanjing General Hospital,People’s Liberation army,Nanjing 210002,Jiangsu Province,China Nanjing university Research Institute of General Surgery Naning General Hospital People's Liberation Army Jiangsu Province China. wang_xb@***

AIM:To investigate the sequential changes of body composition in the metablic response that occurred in a group of patients with entercutaneous fistula after admission to the hospital.

关键词：入院后肠皮肤瘘管患者体况代谢变化