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A cross-layer approach to enable multipacket transmission in MIMO-SDMA based WLAN

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 271-278页

作者： Sheng-bo CHEN Wei CHEN Wei-lan HUANG Li-jun ZHAI xu-ming liu Department of Electronic Engineering. Tsinghua University Beijing 100084 China Nokia Research Center Beijing 100176 China

We propose a medium access control(MAC) protocol for uplink transmissions in wireless local area networks(WLANs),where both stations and access points(APs) are equipped with multiple antennas. The protocol solves some common problems in utilizing multiple input multiple output(MIMO) under the 802.11 protocol,e.g.,how to deploy preamble(training sequence) used for channel estimation and how to enable simultaneous data transmissions,and facilitates two simultaneous uplink data transmissions via a cross-layer approach. Furthermore,we develop a 3D discrete-time Markov model to analyze the per-formance of the proposed WLAN scheme. The analytical results are verified by simulation,and numerical results show that the system throughput can be significantly improved by our proposed scheme as compared with conventional schemes.

关键词： Multiple input multiple output (MIMO) Medium access control (MAC) Cross-layer design

A review of thickness-induced evolutions of microstructure and superconducting performance of REBa2Cu3O7-δ coated conductor

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Advances in Manufacturing 2017年第2期5卷 165-176页

作者： Jian-Xin Lin xu-ming liu Chuan-Wei Cui Chuan-Yi Bai Yu-ming Lu Feng Fan Yan-Qun Guo Zhi-Yong liu Chuan-Bing Cai Shanghai Key Laboratory of High Temperature Superconductors Shanghai University Shanghai 200444People's Republic of China

The research and development of high temperature superconducting （HTS） films, especially ReBa2Cu3- O7-δ （REBCO or RE123; RE=Y, Gd, or other rare earths） yttrium-based coated conductors, has generated widespread interest for the potential applications of the second generation superconducting films. In view of commercialization, however, the maximum superconducting currents for coated conductors should be increased further. Unfortunately, it has been frequently observed that the average critical current density Jc decreases with an increase in film thickness. The thickness effect is still a hurdle for largescale production, especially in pulsed laser deposition and metal organic deposition processes. An engineering current of more than 1 000 A/cm is desired owing to the high cost of 2G superconducting materials. The present work attempts to review the evolution of various issues subject to the thickness effect, including the microstructure, epitaxial texture, surface roughness, pinning force, oxygen deficiency, residual stress, copper-rich layers, and segregation of elements. Furthermore, recent progress in enhancing the performance of superconductors especially in terms of critical current density is illustrated, such as the use of heavy doping. Further understanding of the thickness effect is extremely important for large-scale commercial development of the second generation high temperature superconductors.

关键词： Thickness effect Superconducting film Critical current density Microstructure Epitaxial texture Pinning force

High RF power tests of the first 1.3 GHz fundamental power coupler prototypes for the SHINE project

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Nuclear Science and Techniques 2022年第1期33卷 107-119页

作者： Zhen-Yu Ma Shen-Jie Zhao xu-ming liu Yue-Chao Yu Hong-Ru Jiang Xiang Zheng Qiang Chang Zi-Gang Zhang Kai xu Yan Wang Yu-Bin Zhao Hong-Tao Hou Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

The Shanghai High Repetition Rate XFEL and Extreme Light Facility(SHINE)project will use 6001.3 GHz fundamental power couplers,which are modified based on TTF-Ⅲ power couplers,for continuous-wave operation with input power up to approximately 7 *** first batch of 20 sets of 1.3 GHz coupler prototypes was fabricated from three domestic manufacturers for the SHINE *** better characterize the radio frequency conditioning phenomena for validating the performance of power couplers,a room temperature test stand was designed,constructed,and commissioned for the SHINE 1.3 GHz power *** addition,a horizontal test cryostat was built to test the 1.3 GHz superconducting cavities,fundamental power couplers,tuners,and other components as a *** results of these tests indicate that the 1.3 GHz couplers are capable of handling up to 14 kW continuous ***,the main aspects of the radio frequency design and construction of the test stand,along with the test results of the high-power conditioning of the 1.3 GHz couplers,are described.

关键词： Superconducting accelerating cryomodule 1.3 GHz fundamental power coupler RF conditioning Test bench Horizontal test cryostat

Clinical observation of salvianolic acid B in treatment of liver fibrosis in chronic hepatitis B

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World Journal of Gastroenterology 2002年第4期8卷 679-685页

作者： Ping liu Yi-Yang Hu Cheng liu Hui-ming xue Zhi-Qiang xu Lie-ming xu Cheng-Hai liu Hong-Tu Gu Shanghai University of Traditional Chinese Medicine,Shanghai 200032,China Da-Yuan Zhu Shanghai Institute of Metaria Medica,Chinese Academy of Sciences,Shanghai 200031,China Zhi-Qing Zhang the 4~(th) Hualyin City Hospital,Hualan City,223000,JiangSu Province,China Shanghai University of Traditional Chinese Medicine Shanghai 200032 China. liuliver@***

AIM: To evaluate the clinical efficacy of salvianolic acidB (SA-B) on liver fibrosis in chronic hepatitis ***: Sixty patients with definite diagnosis of liverfibrosis with hepatitis B were included in the ***-γ (IFN-γ) was used as control drug. Thepatients took orally SA-B tablets or received muscularinjection of IFN-γ in the double blind randomized test,The complete course lasted 6 months. The histologicalchanges of liver biopsy specimen before and after thetreatment were the main evidence in evaluation, incombination with the results of contents of serum HA,LN, Ⅳ-C, P-Ⅲ-P, liver ultrasound imaging, andsymptoms and ***: Reverse rate of fibrotic stage was 36.67 % inSA-B group and 30.0 % in IFN-γgroup. Inflammatoryalleviating rate was 40.0 % in SA-B group and 36.67 %in IFN-γ group. The average content of HA and Ⅳ-Cwas significantly lower than that before treatment. Theabnormal rate also decreased remarkably. Overallanalysis of 4 serological fibrotic markers showedsignificant improvement in SA-B group as comparedwith the IFN-γgroup. Score of liver ultrasound imagingwas lower in SA-B group than in IFN-γgroup (HA 36.7 %vs80 %,Ⅳ-C 3.3 % vs23.2 %). Before the treatment,ALT AST activity and total bilirubin content of patientswho had regression of fibrosis after oral administrationof SA-B, were significantly lower than those of patientswho had aggravation of fibrosis after oraladministration of SA-B. IFN-γ showed certain sideeffects (fever and transient decrease of leukocytes,occurrence rates were 50 % and 3.23 %), but SA-Bshowed no side ***: SA-B could effectively reverse liverfibrosis in chronic hepatitis B. SA-B was better than IFN-γ in reduction of serum HA content, overall decrease of4 serum fibrotic markers, and decrease of ultrasoundimaging score. Liver fibrosis in chronic hepatitis B withslight liver injury was more suitable to SA-B in anti-fibrotic treatment. SA-B showed no obvious side effects.

关键词：丹酚乙酸治疗乙型肝炎肝纤维化临床观察

Surgery for left ventricular aneurysm after myocardial infarction： techniques selection and results assessment

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Chinese Medical Journal 2012年第24期125卷 4373-4379页

作者： CHEN Xin QIU Zhi-bing xu ming liu Le-le JIANG Ying-shuo WANG Li-ming Department of Thoracic & Cardiovascular Surgery Nanjing First Hospital Nanjing Medical University Nanjing Heart Institute Nanjing Jiangsu 210006 China

Background The most appropriate surgical approach for patients with post-infarction left ventricular （LV） aneurysm remains undetermined. We compared the efficacy of the linear versus patch repair techniques, and investigated the mid-term changes of LV geometry and cardiac function, for repair of LV aneurysms. Methods We reviewed the records of 194 patients who had surgery for a post-infarction LV aneurysm between 1998 and 2010. Short-term and mid-term outcomes, including complications, cardiac function and mortality, were assessed. LV end-diastolic and systolic dimensions （LVEDD and LVESD）, LV end-diastolic and end-systolic volume indexes （LVEDVI and LVESVI） and LV ejection fraction （LVEF） were measured on pre-operative and follow-up echocardiography. Results Overall in-hospital mortality was 4.12%, and major morbidity showed no significant differences between the two groups. Multivariate analysis identified preoperative left ventricular end diastolic pressure 〉20 mmHg, low cardiac output and aortic clamping time 〉2 hours as risk factors for early mortality. Follow-up revealed that LVEF improved from 37% pre-operation to 45% 12 months post-operation in the patch group （P=0.008）, and from 44% pre-operation to 40% 12 months postoperation in the linear group （P=0.032）. In contrast, the LVEDVI and LVESVI in the linear group were significantly reduced immediately after the operation, and increased again at follow-up. However, in the patch group, the LVEDVI and LVESVI were significantly reduced at follow-up. And there were significant differences in the correct value changes of LVEF and left ventricular remodeling between linear repair and patch groups. Conclusions Persistent reduction of LV dimensions after the patch repair procedure seems to be a procedure-related problem. The choice of the technique should be tailored on an individual basis and surgeon＇s preference. The patch remodeling technique results in a better LVEF improvement, further significant reductions in L

关键词： left ventricular aneurysm post-infarction linear repair patch remodeling left ventricular remodeling

The Genetic Diversity and Phylogenetic Status of Luxi Cattle

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Agricultural Sciences in China 2006年第8期5卷 629-634页

作者： MAO Yong-jiang CHANG Hong YANG Zhang-ping xu ming ZHANG liu CHANG Guo-bin SONG Wei- tao WANG Dong-lei Animal Science and Technology College Yangzhou University Yangzhou 225009 P.R.China

A total of 87 individuals of Luxi cattle from Juanchen and Liangshan counties, Shangdong Province, China, were sampled by simple random sampling in typical colony. Twenty-one blood proteins and enzymes loci were detected by polyacrylamide gel electrophoresis （PAGE） and starch gel electrophoresis （SGE）. In the meantime, the data of 7 loci of 13 cattle populations in China and other countries were collected and phylogeny relationships were studied. The results indicated that 9 out of 21 loci showed polymorphism （42.86%）; the level of genetic variation in Luxi cattle population was relatively high, the mean heterozygosity was 0.1416. The Luxi cattle have a close phylogenetic relationship with the cattle populations of east and south of Asia, and this further confirmed the fact that Luxi cattle were the cross-breed between the Bos taurus and Bos indicus in China, but it is impossible that yellow cattle contained the blood of of Bali.

关键词： Luxi cattle genetic diversity cluster analysis

Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise

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Neural Regeneration Research 2025年第3期20卷 836-844页

作者： Do-Hun Lee Dan Cao Younghye Moon Chen Chen Nai-Kui liu Xiao-ming xu Wei Wu Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteIndiana University School of MedicineIndianapolisINUSA Department of Neurological Surgery Indiana University School of MedicineIndianapolisINUSA Department of Neuroscience Baylor College of MedicineHoustonTXUSA

Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.

关键词： behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise

Regulation and function of endoplasmic reticulum autophagy in neurodegenerative diseases

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Neural Regeneration Research 2025年第1期20卷 6-20页

作者： Xiu-Yun Zhao De-En xu ming-Lei Wu Ji-Chuan liu Zi-Ling Shi Quan-Hong Ma Department of Neurology and Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Neuroscience&Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhouJiangsu ProvinceChina Department of Neurology Jiangnan University Medical CenterWuxiJiangsu ProvinceChina

The endoplasmic reticulum,a key cellular organelle,regulates a wide variety of cellular *** reticulum autophagy,one of the quality control systems of the endoplasmic reticulum,plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover,remodeling,and *** this review,we briefly describe the endoplasmic reticulum quality control system,and subsequently focus on the role of endoplasmic reticulum autophagy,emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular *** also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative *** summary,this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve *** review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

关键词： autophagy endoplasmic reticulum endoplasmic reticulum autophagy endoplasmic reticulum quality control system endoplasmic reticulum receptors endoplasmic reticulum-associated degradation neurodegeneration neurodegenerative disease selective autophagy unfolded protein response

Effect of recombinant human growth hormone and interferon gamma on hepatic collagen synthesis and proliferation of hepatic stellate cells in cirrhotic rats

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Hepatobiliary & Pancreatic Diseases International 2012年第3期11卷 294-301页

作者： Yong-Hua Chen, Bing-Qing Du, Zhen-Jiang Zheng, Guang-ming Xiang, xu-Bao liu and Gang Mai Department of Hepatobiliopancreatic Surgery, West China Hospital, Sichuan University, Chengdu 610041, China Department of Hepatobiliopancreatic Surgery West China Hospital Sichuan University Chengdu 610041 China

BACKGROUND: Fibrosis plays a key role in the development of liver cirrhosis. In this study, we investigated the effect of growth hormone and interferon gamma on hepatic collagen synthesis and the proliferation of hepatic stellate cells in a cirrhotic rat model. METHODS: Cirrhosis was induced in rats using carbon tetrachloride. Rats were simultaneously treated with daily subcutaneous injections of recombinant human growth hormone or interferon gamma combined with recombinant human growth hormone. The control group was given saline. The relative content of type I and type IV collagen was assessed by indirect immunofluorescence analysis. Activated hepatic stellate cells were prepared from cirrhotic rats. The 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) method was used to assess the effects of recombinant human growth hormone and interferon gamma on these cells in vitro. RESULTS: Both qualitative and quantitative analysis showed that type I and type IV collagen secretion increased with time after recombinant human growth hormone administration and was significantly higher than control and recombinant human growth hormone combined with interferon gamma administration. In vitro, recombinant human growth hormone significantly stimulated hepatic stellate cell proliferation in a concentration-dependent manner (10 -3 -10 -1 mg/100 μL), andinterferon gamma (10 -2 -10 -1 μg/100 μL) significantly inhibited their growth compared to the control group. Interferon gamma combined with recombinant human growth hormone eliminated this growth-promoting effect to a certain degree in a concentration-dependent manner (10 -1 μg/100 μL, P0.05) and a time-dependent manner (P<0.05). CONCLUSIONS: Recombinant human growth hormone increased collagen secretion in cirrhotic rats in vivo and promoted the proliferation of hepatic stellate cells from cirrhotic rats in vitro. It is possible that concurrent interferon gamma therapy can offset

关键词： growth hormone interferon gamma hepatic stellate cell liver cirrhosis collagen