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Postprandial triglyceride metabolism in elderly men with subnormal testosterone levels

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Asian Journal of Andrology 2008年第4期10卷 542-549页

作者： Ingvild Agledahl John-Bjarne hansen Johan Svartberg Department of Medicine University Hospital of North Norway TromsO 9038 Norway Center for Atherothrombotic Research in TromsФ （CART） Institute of Clinical Medicine University of TromsФ TromsФ 9037 Norway institute of Clinical Medicine University of TromsФ TromsФ 9037 Norway

Aim： To investigate the level of postprandial triglycerides （Tg）s in elderly men with subnormal testosterone level （≤ 11.0 nmol/L） compared to men with normal testosterone level （〉 11.0 nmol/L）. Methods： Thirthy-seven men with subnormal and 41 men with normal testosterone aged 60-80 years underwent an oral fat load and Tg levels were measured fasting and 2, 4, 6 and 8 h afterwards. Results： Men with subnormal testosterone had significantly higher body mass index （BMI） and waist circumference （P 〈 0.001） than men with normal testosterone. They had significantly higher area under curve （AUC, P = 0.037）, incremental area under curve （AUCi, P = 0.035） and Tg response （TgR, P = 0.014） for serum-Tg and significantly higher AUC （P = 0.023）, AUCi （P = 0.023） and TgR （P = 0.014） for chylomicron-Tg compared to men with normal testosterone level. Adjusting for waist circumference erased the significant differences between the groups in postprandial triglyceridemia. Conclusion： Men with subnormal testosterone have increased postprandial Tg levels indicating an impaired metabolism of postprandial Tg-rich lipoproteins （TRL）, which may add to an unfavourable lipid profile and promote development of atherosclerosis.

关键词： testosterone sex hormone-binding globulin postprandial triglycerides abdominal obesity waist circumference

Coupling Ensemble Kalman Filter with Four-dimensional Variational Data Assimilation

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Advances in Atmospheric Sciences 2009年第1期26卷 1-8页

作者： Fuqing ZHANg Meng ZHANg James A. hansen Department of Meteorology Pennsylvania State University University Park Pennsylvania USA Navy Research Laboratory Monterrey California USA

This study examines the performance of coupling the deterministic four-dimensional variational assimilation system （4DVAR） with an ensemble Kalman filter （EnKF） to produce a superior hybrid approach for data assimilation. The coupled assimilation scheme （E4DVAR） benefits from using the state-dependent uncertainty provided by EnKF while taking advantage of 4DVAR in preventing filter divergence： the 4DVAR analysis produces posterior maximum likelihood solutions through minimization of a cost function about which the ensemble perturbations are transformed, and the resulting ensemble analysis can be propagated forward both for the next assimilation cycle and as a basis for ensemble forecasting. The feasibility and effectiveness of this coupled approach are demonstrated in an idealized model with simulated observations. It is found that the E4DVAR is capable of outperforming both 4DVAR and the EnKF under both perfect- and imperfect-model scenarios. The performance of the coupled scheme is also less sensitive to either the ensemble size or the assimilation window length than those for standard EnKF or 4DVAR implementations.

关键词： data assimilation four-dimensional variational data assimilation ensemble Kalman filter Lorenz model hybrid method

Oxygen radical formation does not have an impact in the treatment of severe acute experimental pancreatitis using free cellular hemoglobin

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World Journal of gastroenterology 2006年第18期12卷 2914-2918页

作者： Helge Kleinhans Oliver Mann Paulus g Schurr Jussuf T Kaifi Bente hansen Jakob R Izbicki Tim Strate Department of general- Visceral- and Thoracic SurgeryUniversity Medical Center Hamburg-EppendorfMartinistrasse 52D-20246 HamburgGermany

AIM： Microcirculatory dysfunction and free oxygen radicals are important factors in the pathogenesis of severe acute pancreatitis. Additional oxygen delivery might enhance lipid peroxidation but may also improve pancreatic microcirculation. This study assesses the effect of free cellular bovine hemoglobin on the formation of oxygen radicals and microcirculation in a rodent model of severe acute pancreatitis. METHODS： Fifteen minutes after induction of acute pancreatitis Wistar rats received either 0.8 mL bovine hemoglobin （HBOC-200）, hydroxyethyl starch （HES） or 2.4 mL of normal saline to ensure normovolemic substitution. After 6 h of examination the pancreas was excised and rapidly processed for indirect measurement of lipid peroxidation products malondialdehyde （MDA） and reduced glutathione （gSH） in pancreatic tissue. RESULTS： The single application of HBOC-200 improved pancreatic microcirculation and reduced histopathological tissue damage significantly. Tissue concentration of MDA did not differ between the groups. Also no differences in gSH levels were detected.CONCLUSION： Though the single application of HBOC-200 and HES improve pancreatic microcirculation, no differences in lipid peroxidation products were detected. The beneficial effect of additional oxygen supply （HBOC-200） does not lead to enhanced lipid peroxidation.

关键词： Hemoglobin-based-oxygen-carrier HBOC Blood substitudes Severe acute pancreatitis Free oxygen radicals Oxidative stress

Effectiveness of a Passive-active Vibration Isolation System with Actuator Constraints

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 567-574页

作者： SUN Lingling SUN Wei SONg Kongjie hansen Colin H Key Laboratory of High-efficiency and Clean Mechanical Manufacture Shandong University School of Mechanical Engineering University of Adelaide

In the prediction of active vibration isolation performance, control force requirements were ignored in previous work. This may limit the realization of theoretically predicted isolation performance if control force of large magnitude cannot be supplied by *** behavior of a feed-forward active isolation system subjected to actuator output constraints is investigated. Distributed parameter models are developed to analyze the system response, and to produce a transfer matrix for the design of an integrated passive-active isolation system. Cost functions comprising a combination of the vibration transmission energy and the sum of the squared control forces are proposed. The example system considered is a rigid body connected to a simply supported plate via two passive-active isolation mounts. Vertical and transverse forces as well as a rotational moment are applied at the rigid body, and resonances excited in elastic mounts and the supporting plate are analyzed. The overall isolation performance is evaluated by numerical simulation. The simulation results are then compared with those obtained using unconstrained control strategies. In addition, the effects of waves in elastic mounts are analyzed. It is shown that the control strategies which rely on tmconstrained actuator outputs may give substantial power transmission reductions over a wide frequency range, but also require large control force amplitudes to control excited vibration modes of the system. Expected power transmission reductions for modified control strategies that incorporate constrained actuator outputs are considerably less than typical reductions with unconstrained actuator outputs. In the frequency range in which rigid body modes are present, the control strategies can only achieve 5-10 dB power transmission reduction, when control forces are constrained to be the same order of the magnitude as the primary vertical force. The resonances of the elastic mounts result in a notable increase of

关键词： passive-active isolation transfer matrix control effort constraint feedforward control

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基于改进卷积神经网络的信号调制识别

舰船电子对抗 2024年第2期47卷 81-85页

作者：李瀚森黄华王铎澎中国船舶集团有限公司第七二三研究所江苏扬州225101

信号调制识别是通信侦察的重要环节。在现代战争中,信号密度日益增大、波形更加复杂、调制类型越来越多、环境干扰大等情况都导致通信侦察的电磁环境更加复杂,信号调制识别越来越困难。近年来神经网络算法得到了极大的发展,卷积神经网... 详细信息

信号调制识别是通信侦察的重要环节。在现代战争中,信号密度日益增大、波形更加复杂、调制类型越来越多、环境干扰大等情况都导致通信侦察的电磁环境更加复杂,信号调制识别越来越困难。近年来神经网络算法得到了极大的发展,卷积神经网络算法被广泛应用于各个领域。应用一种改进卷积神经网络进行信号的调制识别工作,得到了较为准确的识别效果。

关键词：信号调制识别卷积神经网络深度学习

Rapid mapping of alloy surface phase diagrams via Bayesian evolutionary multitasking

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npj Computational Materials 2023年第1期9卷 905-918页

作者： Shuang Han Steen Lysgaard Tejs Vegge Heine Anton hansen Department of Energy Conversion and Storage Technical University of DenmarkAnker EngelundsvejBuilding 3012800 Kgs.LyngbyDenmark

Surface phase diagrams(SPDs)are essential for understanding the dependence of surface chemistry on reaction *** multi-component systems such as metal alloys,the derivation of such diagrams often relies on separate first-principles global optimization tasks under different reaction *** we show that this can be significantly accelerated by leveraging the fact that all tasks essentially share a unified configurational search space,and only a single expensive electronic structure calculation is required to evaluate the stabilities of a surface structure under all considered reaction *** a general solution,we propose a Bayesian evolutionary multitasking(BEM)framework combining Bayesian statistics with evolutionary multitasking,which allows efficient mapping of SPDs even for very complex surface *** proofs of concept,we showcase the performance of our methods in deriving the alloy SPDs for two heterogeneous catalytic systems:the electrochemical oxygen reduction reaction(ORR)and the gas phase steam methane reforming(SMR)reaction.

关键词： alloy surface diagrams

Reveal heterogeneous motion states in single nanoparticle trajectory using its own history

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Science China Chemistry 2021年第2期64卷 302-312页

作者： hansen Zhao Feng ge Sichun Zhang Xinrong Zhang Yan He Department of Chemistry Tsinghua UniversityBeijing100084China

Single particle tracking(SPT)has long been utilized for investigation of complex system dynamics such as nanoparticle-cell interaction,however,the analysis of individual particle motions is always a difficult *** methods treat each data point or fragment on the recorded trajectory as an isolated"atom"and determine their relationship based on externally predefined models or physical states,which inevitably lead to oversimplification of the associated spatiotemporal ***,inspired by the historical analysis in social science,we propose a modeless preprocessing framework for SPT analysis based on the"history"of the *** new strategy consists of 3 steps:(1)assign a"history"to each data point and construct successive overlapped historical vectors;(2)perform unsupervised clustering in the vector space to find their relative differences;(3)project differences back to the trajectory by coloring each point accordingly for *** a result,the inner heterogeneity of the particle motion self-emerges as a colored trajectory,exhibiting a global picture of the local state transitions and providing valuable information for further model-based *** the complexity issues at various spatiotemporal scales have attracted increasing attention,and individual objects such as single molecules,cells,vehicles and even stars in the universe could all be treated as"single particles",this presuppositionless data preprocessing approach could help the investigations of many complex systems in fundamental research.

关键词： single particle tracking nanoparticle machine learning

基于高通量测序的三峡库区重庆段黄胸鼠肠道菌群分析

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中国微生态学杂志 2024年第5期36卷 504-511,517页

作者：王玲肖汉森何亚明李志峰赵婷段刚重庆市疾病预防控制中心重庆400707 高致病性病原微生物重庆市重点实验室重庆400707

目的研究三峡库区重庆段黄胸鼠肠道细菌的群落结构和多样性,初步了解库区黄胸鼠携带病原体的本底资料。方法对三峡库区重庆段32例黄胸鼠的粪便样品进行16SrDNA高通量测序,分析黄胸鼠肠道菌群多样性、丰度和群落结构。结果三峡库区重庆... 详细信息

目的研究三峡库区重庆段黄胸鼠肠道细菌的群落结构和多样性,初步了解库区黄胸鼠携带病原体的本底资料。方法对三峡库区重庆段32例黄胸鼠的粪便样品进行16SrDNA高通量测序,分析黄胸鼠肠道菌群多样性、丰度和群落结构。结果三峡库区重庆段黄胸鼠肠道菌群主要以厚壁菌门、拟杆菌门和变形菌门为主。在属水平上,优势菌属包括乳杆菌属、Cellulosilyticum、八叠球菌属等。不同县(区)黄胸鼠肠道菌群结构不同,丰都县(FD)和陵区(FL)的菌群结构相似度较高,巫山县(WS)、开州区(KZ)、忠县(ZX)、奉节县(FJ)和云阳县(YY)5个区县群落结构相似度较高;三峡库区重庆段黄胸鼠肠道菌群结构相似度秋季明显高于春季。32份鼠粪样本测序结果提示含有葡萄球菌属、双歧杆菌属、沙门氏菌属、螺杆菌属等致病菌和条件致病菌。结论初步了解了三峡库区重庆段黄胸鼠的肠道菌群特征以及库区内地域性、季节性差异,黄胸鼠肠道中携带大量的致病菌和条件致病菌,应引起高度重视。

关键词：三峡库区黄胸鼠高通量测序肠道菌群物种多样性

A concurrent optimization approach for energy efficient multiple axis positioning tasks

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Journal of Control and Decision 2016年第4期3卷 223-247页

作者： Christian hansen Jens Kotlarski Tobias Ortmaier Institute of Mechatronic Systems Leibniz Universitat HannoverHanoverGermany

Automated production systems typically comprise numerous electrical servo drives,many of which conduct positioning motions,*** handling or manipulation *** power electronics of modern multi-axis systems often comprise coupled DC-links,enabling for internal exchange of recuperative brake ***,the motion sequences of manipulators are often commanded at maximum dynamics for minimum time motion,neglecting possible optimization potential,*** idle time,leading to inefficient energy management.A robust trajectory optimization approach based on the particle swarm algorithm and well-established path planning methods is presented for the adaption of multi-axis positioning tasks with only two parameters per axis and positioning motion during system *** results prove that,depending on the positioning task and chosen optimization constraints,energy demands are distinctly *** approach is applicable to diverse multi-axis configurations and enables for considerable energy savings without additional hardware invest.

关键词： Multiple axis systems electrical servo drive energy efficient control trajectory optimization positioning tasks