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Configuration synthesis of planar folded and common overconstrained spatial rectangular pyramid deployable truss units

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Chinese Journal of Aeronautics 2019年第7期32卷 1772-1787页

作者： Hui YANG Hongwei GUO Yan WANG Rongqiang LIU Zongquan DENG College of Electrical Engineering and Automation Anhui UniversityHefei230601China State Key Laboratory Robotics and System Harbin Institute of TechnologyHarbin150001China China Electronics Technology Group Corporation No.38Research Hefei230088China

Compared with non-overconstrained deployable units, overconstrained deployable units are widely used in space missions for their higher stiffness characteristics. Besides the performance of a three-step topological structural analysis and design of the rectangular pyramid deployable truss unit(PDTU), conducting a structural synthesis of an overconstrained deployable unit requires the determination of the relative position and direction of each kinematic axis. The structural synthesis of an overconstrained deployable unit is investigated based on screw theory and its topological structure. The possible overconstrained cases of the rectangular PDTUs are analyzed, and corresponding screw expressions are obtained. Thus, the rectangular PDTUs, which can be folded into a plane, are synthesized systemically, and a series of overconstrained rectangular PDTUs is obtained. Furthermore, the feasibility of the folded and deployed motions under one degree of freedom for those deployable units is verified in dynamical simulation by using ADAMS 2010.

关键词： Assembly SAR antenna common overconstraint Deployable truss structure Screw theory Structural synthesis

common effluent treatment plant(CETP):Reliability analysis and performance evaluation

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Water Science and Engineering 2018年第3期11卷 205-213页

作者： Ashwini V.Padalkar Rakesh Kumar CSIR-National Environmental Engineering Research Institute(NEERI) Mumbai 400018India

common effluent treatment plants(CETPs) have been installed and are in operation at numerous industrial clusters throughout India. They serve to reduce effluent treatment cost, provide better collective treatment, and reduce land cost for small-scale industrial facilities that cannot afford individual treatment plants. Optimum working conditions for treatment of effluent to be at par with discharge standards is a major mandate for any CETP. In this study, the reliability and removal efficiencies(REs) of a CETP in the industrial area of Maharashtra State in India were examined. An established methodology was adopted to determine the effectiveness of the CETP in terms of biochemical oxygen demand(BOD), chemical oxygen demand(COD), total suspended solids(TSS), and oil and grease(O&G) concentrations. The CETP's compliance with respect to design standards and its operation were studied in detail. This paper highlights the results of RE and the coefficient of determination(R2) values obtained from the CETP data, estimates the pollutants removed at the highest and lowest rates over a period of time, and highlights the reasons for problem areas along with remedial measures. It was observed that, except O&G, all the parameters(BOD, COD, and TSS)showed fluctuations in removal efficiencies and their reliabilities. This situation can be improved by releasing effluent containing hydraulic and organic loading to the CETP as per standards and optimizing treatment processes, especially primary clari-flocculators and aeration tanks, both of which are important units of any CETP.

关键词： Aeration tank Clari-flocculator Coefficient of reliability Coefficient of variation common effluent treatment plant Removal efficiency Reliability analysis

common Infections May Lead to Alzheimer's Disease

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Virologica Sinica 2018年第5期33卷 456-458页

作者： Yuyan Wang Ling Ding Qing Zhu Minfeng Shu Qiliang Cai MOE & MOH Key Laboratory of Medical Molecular Virology School of Basic Medicine Shanghai Medical College Fudan University

Alzheimer's disease (AD),also known as Alzheimer's,is a chronic neurodegenerative disorder with hallmark amyloid plaques in brain *** diseases commences slowly and worsens over time (Sjogren et al.1952).Although it has been investigated for over six decades,the cause of AD is still not completely *** was initially thought to be caused by genetic heritability (autosomal mutation leading to aggregation of β-amyloid and misfolded tau proteins)or head ***,hundreds of drug trials targeting the accumulation of sticky amyloid plaques and misfolded tau proteins in the brain have failed to yield any results.

关键词： common Infections Alzheimer's Disease

common bile duct stones on multidetector computed tomography:Attenuation patterns and detectability

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World Journal of Gastroenterology 2013年第11期19卷 1788-1796页

作者： Chang Whan Kim Jae Hyuck Chang Yeon Soo Lim Tae Ho Kim In Seok Lee Sok Won Han Department of Internal Medicine College of MedicineThe Catholic University of Korea505 BanpoDongSeocho-GuSeoul 137-701South Korea Department of Radiology College of MedicineThe Catholic University of Korea505 Banpo-DongSeocho-GuSeoul 137-701South Korea

AIM:To investigate the attenuation patterns and detectability of common bile duct(CBD) stones by multidetector computed tomography(MDCT).METHODS:Between March 2010 and February 2012,191 patients with suspicion of CBD stones undergoing both MDCT and endoscopic retrograde cholangiopancreatography(ERCP) were enrolled and reviewed *** attenuation patterns of CBD stones on MDCT were classified as heavily calcified,radiopaque,less radiopaque,or *** association between the attenuation patterns of CBD stones on MDCT and stone type consisting of pure cholesterol,mixed cholesterol,brown pigment,and black pigment and the factors related to the detectability of CBD stones by MDCT were ***:MDCT showed CBD stones in 111 of 130 patients in whom the CBD stones were demonstrated by ERCP with 85.4% *** attenuation patterns of CBD stones on MDCT were heavily calcified 34(26%),radiopaque 31(24%),less radiopaque 46(35%),and undetectable 19(15%).The radiopacity of CBD stones differed significantly according to stone type(P < 0.001).From the receiver operating characteristic curve,stone size was useful for the determination of CBD stone by MDCT(area under curve 0.779,P < 0.001) and appropriate cut-off stone size on MDCT was 5 *** factors related to detectability of CBD stones on MDCT were age,stone type,and stone size on multivariate analysis(P < 0.05).CONCLUSION:The radiopacity of CBD stones on MDCT differed according to stone *** type and stone size were related to the detectability by MDCT,and appropriate cut-off stone size was 5 mm.

关键词： common bile duct gallstones Gallstones Multidetector computed tomography Endoscopic retrograde cholangiography

The class of supernova progenitors that result from fatal common envelope evolution

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 35-46页

作者： Noam Soker Department of Physics Technion – Israel Institute of Technology Guangdong Technion Israel Institute of Technology

I construct the class of supernovae and supernova progenitors that result from fatal common envelope evolution(CEE). The fatal CEE progenitors are stellar binary systems where a companion spirals-in inside the envelope of a giant star and merges with the core. The companion can be a neutron star(NS;or a black hole) that destroys the core and by that forms a common envelope jets supernova(CEJSN), a white dwarf(WD) that merges with the core to form a massive WD that later might explode as a Type Ia supernova(the core degenerate scenario), or a main sequence companion. In the latter case the outcome might be a core collapse supernova(CCSN) of a blue giant, a CCSN of type IIb or of type Ib. In another member of this class two giant stars merge and the two cores spiral-in toward each other to form a massive core that later explodes as a CCSN with a massive circumstellar matter(CSM). I discuss the members of this class, their characteristics, and their common properties. I find that fatal CEE events account for ≈6%-10% of all CCSNe, and raise the possibility that a large fraction of peculiar and rare supernovae result from the fatal CEE. The study of these supernova progenitors as a class will bring insights on other types of supernova progenitors, as well as on the outcome of the CEE.

关键词： common envelope evolution(CEE) supernovae binary and multiple stars neutron stars white dwarfs

Introduction to the benchmark challenge on common rail pressure control of gasoline direct injection engines

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Control Theory and Technology 2019年第2期17卷 167-175页

作者： Qifang LIU Jinlong HONG Bingzhao GAO Hong CHEN State Key Laboratory of Automotive Simulation and Control Changchun Jilin 130025China Department of Control Science and Engineering Jilin UniversityChangchun Jilin 130025China

As one of the most important actuators for gasoline direct injection technology,common rail systems provide the requested rail pressure for fuel *** system characteristics,such as coupled discrete-continuous dynamic in the common rail system,limited measurable states,and time-varying engine operating conditions,impel the combination of advanced methods to obtain the desired injection ***,reducing the pressure fluctuation and satisfying engineering implementation have become noteworthy issues for rail pressure control(RPC)*** this study,the benchmark problem and the design specification of RPC proposed by 2018 IFAC E-CoSM Committee are ***,a common rail system model is provided to the challengers,and a traditional PI control is applied to show the problem ***,intermediate results of the challengers are summarized briefly.

关键词： common rail pressure control gasoline direct injection engine control system design benchmark challenge

common iliac artery occlusion with small intestinal transection caused by blunt abdominal trauma: A case report and review of the literature

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World Journal of Clinical Cases 2019年第15期7卷 2120-2127页

作者： You-Xin Zhou Yong Ji Jing Chen Xin Yang Qing Zhou Jian Lv Department of General Surgery People’s Hospital of JingjiangYangzhou University Medical AcademyJingjiang 214500Jiangsu ProvinceChina Imaging Department People’s Hospital of JingjiangYangzhou University Medical AcademyJingjiang 214500Jiangsu ProvinceChina Department of General Surgery Affiliated Hospital of Jiangsu UniversityZhenjiang 212000Jiangsu ProvinceChina

BACKGROUND Most major abdominal vascular injuries are caused by penetrating injuries.A common iliac artery occlusion caused by blunt force trauma is rare,and very few cases have been *** of this low incidence,atypical symptoms,and frequent association with other severe injuries,the proper diagnosis tends to be missed or *** gold standard for diagnosis is angiography,and treatment remains a *** SUMMARY We report here the unusual case of a common iliac artery occlusion caused by blunt abdominal compressive trauma,with transection of the small *** presentation,the patient(a 56-year-old man)complained of pain and numbness in the left lower extremity and severe pain in the whole *** examination showed total abdominal tenderness with evidence of peritoneal *** left lower limb was pulseless and *** computed tomography examination revealed digestive tract perforation,and abdominal computed tomography angiography showed left common iliac artery *** patient was treated successfully by anastomosis of the intestine,percutaneous transluminal angioplasty,and *** patient was followed for more than 11 mo after the operation and showed a good *** Patients with abdominal trauma should be suspected of having major vascular *** treatment strategies are needed for this condition.

关键词： common iliac artery occlusion Transection of the small intestine Blunt abdominal trauma Case report Percutaneous transluminal angioplasty Anastomosis of the intestine

Abundance and prey capture success of common Terns(Sterna hirundo)and Pied Kingfishers(Ceryle rudis)in relation to water clarity in south-east coastal Ghana

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Avian Research 2018年第3期9卷 226-238页

作者： Lars H.Holbech Francis Gbogbo Timothy Khan Aikins Department of Animal Biology and Conservation Science University of GhanaP.O.Box LG 67LegonAccraGhana Department of Biodiversity Conservation and Management University for Development StudiesBox TL 1882Nyankpala CampusTamaleGhana

Background: Water clarity may negatively influence rate of plunge diving and prey capture success of piscivorous plunge-diving birds, and therefore has implications for their conservation in polluted urban wetlands. We studied the relationship between water clarity and the abundance and prey capture success of Pied Kingfishers(Ceryle rudis) and common Terns(Sterna hirundo) in two polluted coastal waters of south-east Ghana—the Weija Lake and Densu Delta Ramsar ***: On each wetland, data on abundance and prey capture success of plunge-divers were collected in four spatio-temporal quadrats of 100 m × 100 m and analysed with concurrent measurements of water quality parameters using GLM regression with Pearson's correlation ***: Mean prey capture success of Pied Kingfishers(34.7 e two species responded differently to water clarity. The± 13.1%) and common Terns(35.3 abundance of common Terns was± 11.0%) were similar but th significantly higher in less transparent/more turbid water while that of Pied Kingfishers showed no significant relationship with turbidity and transparency. In contrast, the prey capture success of common Terns was neither related to transparency nor turbidity, as opposed to that of Pied Kingfishers which was significantly higher in more turbid/less transparent waters. Correlations between capture success and bird abundance, as well as capture attempts were insignificant, suggesting that increased fish abundance associated with cloudy water may not necessarily promote higher abundance and capture success of foraging birds. Thus, when foraging in less transparent water, capture success may depend more on predator avoidance by fish prey than lower prey detectability of foraging ***: Within a gradient of 15–51 cm transparency studied, lower water clarity did not constrain prey capture success of common Terns and Pied Kingfishers. Further studies on the foraging ecology of plunge-divers in coastal Ghana are however r

关键词： Coastal Ghana common Tern Pied Kingfisher Prey capture success Water turbidity and transparency

Differential gene and protein expression between rat tibial nerve and common peroneal nerve during wallerian degeneration

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Neural Regeneration Research 2019年第12期14卷 2183-2191页

作者： Yao-Fa Lin Zheng Xie Jun Zhou Gang Yin Hao-Dong Lin Department of Orthopedic Surgery Changzheng Hospital the Second Military Medical University Shanghai China Department of Orthopedic Surgery Shanghai General Hospital Shanghai Jiao Tong University School of Medicine Shanghai China

Wallerian degeneration and nerve regeneration after injury are complex processes involving many genes, proteins and cytokines. After different peripheral nerve injuries the regeneration rate can differ. Whether this is caused by differential expression of genes and proteins during Wallerian degeneration remains unclear. The right tibial nerve and the common peroneal nerve of the same rat were exposed and completely cut through and then sutured in the same horizontal plane. On days 1, 7, 14, and 21 after surgery, 1–2 cm of nerve tissue distal to the suture site was dissected out from the tibial and common peroneal nerves. The differences in gene and protein expression during Wallerian degeneration of the injured nerves were then studied by RNA sequencing and proteomic techniques. In the tibial and common peroneal nerves, there were 1718, 1374, 1187, and 2195 differentially expressed genes, and 477, 447, 619, and 495 differentially expressed proteins on days 1, 7, 14, and 21 after surgery, respectively. Forty-seven pathways were activated during Wallerian degeneration. Three genes showing significant differential expression by RNA sequencing (Hoxd4, Lpcat4 and Tbx1) were assayed by real-time quantitative polymerase chain reaction. RNA sequencing and real-time quantitative polymerase chain reaction results were consistent. Our findings showed that expression of genes and proteins in injured tibial and the common peroneal nerves were significantly different during Wallerian degeneration at different time points. This suggests that the biological processes during Wallerian degeneration are different in different peripheral nerves after injury. The procedure was approved by the Animal Experimental Ethics Committee of the Second Military Medical University, China (approval No. CZ20160218) on February 18, 2016.

关键词： nerve regeneration peripheral nerves peripheral nerve injuries Wallerian degeneration tibial nerve common peroneal nerve RNA sequencing proteomic real-time quantitative polymerase chain reaction neural regeneration