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Estimation Algorithm of Contending Stations Based on Improved DCF Model in IEEE 802.11

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The Journal of China Universities of Posts and Telecommunications 2004年第Z1期11卷 44-49页

作者： hu he-fei LIU Yuan-an LI Shu-lan School of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China

The fundamental access method of IEEE 802.11 is a DCF known as carrier sense multiple access with collision avoidance (CSMA/CA) scheme with exponential back-off. RTS__threshold is used to determine whether to deploy RTS/CTS access method. This threshold should vary with the number of contending stations which contend wireless media to get better throughput. The paper proposes an algorithm which estimates the number of contending stations in BSS. The algorithm is shown to be accurate which is verified by elaborate simulations.

关键词： IEEE 802.11 wireless LAN CSMA/CA estimation algorithm model

Waist Circumference Distribution of Chinese School-age Children and Adolescents

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Biomedical and Environmental Sciences 2010年第1期23卷 12-20页

作者： CheNG-YE JI RITA YT SUNG GUAN-SheNG MA JUN MA ZHONG-hu he TIAN-JIAO CheN Institute of ChiM and Adolescent health Peking University Health Science Center Beijing 100191 China Department of Paediatrics The Chinese University of Hong Kong Hong Kong Special Administrative Region China National Institute for Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100021 China

Background Waist circumference （WC）, a proxy measure of central body fat, is a better predictor than overall body fat for cardiovascular risk factors in both adults and children. WC cutoffs have been established in many countries, but the national WC reference has not been developed in China. Objective To study the distribution of WC in a representative group of Chinese children for establishing Chinese WC cutoff points. Methods Cross-sectional data obtained from 15 mainland provinces and Hong Kong were collected. There were 160 225 children and adolescents aged 7-18 years old in total. The subjects were divided into five regional groups namely costal city, other city, noah rural, south rural, and Hong Kong, for analyzing the distribution of WC. Results A large variation in WC distribution was found among the five groups for both sexes. Coastal city group had the highest P85 WC values consistently from the early school ages to 18-year-old compared with other groups. In contrast, south rural group had P85 values consistently lagged behind not only the city groups but also the north rural group. Hong Kong group had a high P85 WC at early ages, but because of the smaller increments of WC during adolescence, the P85 curve was gradually exceeded by the north rural groups. Catch-up trend was found in the two rural groups since the peak of puberty. These disparities were caused by not only socioeconomic and urban-rural factors but also north-south differences. Because of the regional variation of WC, a ＂gradient＂ prevalence of central obesity was prospected among these groups. Comparisons of WC distributions between the Chinese and the U.S.A or Netherlands demonstrated the necessary of setting up China＇s own WC cutoffs. Sex and age-specific percentiles were obtained and smoothed by using LMS method. Conclusion The data obtained from this study could be used to develop national WC cutoff points for Chinese children and adolescents.

关键词： Overweight and obesity Central obesity Waist circumference Chinese youth School-age children and adolescents

Directional hydraulic fracturing to control hard-roof rockburst in coal mines

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International Journal of Mining Science and Technology 2012年第2期22卷 177-181页

作者： Fan Jun Dou Linming he hu Du Taotao Zhang Shibin Gui Bing Sun Xinglin State Key Laboratory of Coal Resources and Mine Safety School of MinesChina University of Mining&TechnologyXuzhou 221116China Coal Mining&Designing Branch China Coal Research InstituteBeijing 100013China Jisan Coal Mine of Yanzhou Mining Industry Group fining 272000China

Hard roof is the main factor that induces *** view of the present obvious weakness of control measures for hard roof rockburst in domestic collieries,the mechanism and field application of directional hydraulic fracturing technology for rock-burst prevention have been investigated in this paper using theoretical analysis and numerical *** results show that the weighting span of the main roof and the released kinetic energy as well as the total elastic energy decreased greatly after the directional fracturing of hard roof with the mining progression,thereby reducing the rockburst hazard degree to coal *** directional hydraulic fracturing technology was carried out in 6305 working face of Jisan Coal Mine to prevent *** practices have proved that this technology is much simpler and safer to operate with better prevention effect compared with *** optimizing the operation procedures and developing a new technology of automated high-pressure delivery pipe,the maximum fracturing radius now reaches more than 9 m and the borehole depth exceeds 20 ***,drilling cutting method was applied to monitor the stress of the coal mass before and after the fracturing,and the drill cuttings dropped significantly which indicates that the burst prevention effect of directional hydraulic fracturing technology is very *** research results of this paper have laid a theoretical and practical foundation for the widespread application of the directional hydraulic fracturing technology in China.

关键词： Hard roofRockburstDirectional hydraulic fracturingSimulation

CLEAR: a full-stack chip-in-loop emulator for analog RRAM based computing-in-memory system

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Science China(Information Sciences) 2023年第12期66卷 293-294页

作者： Ruihua YU Wenqiang ZHANG Bin GAO Yiwen GENG Peng YAO Yuyi LIU Qingtian ZHANG Jianshi TANG Dong WU hu he Ning DENG he QIAN huaqiang WU School of Integrated Circuits Beijing National Research Center for Information Science and Technology(BNRist)Tsinghua University

Deep neural networks(DNNs) have undergone tremendous advancement in several practical applications, such as object detection and text generation, over the last few years,leading to a huge demand for increased computing efficiency of hardware. Resistive random-access memory(RRAM)-based computing-in-memory(CIM) chip has been investigated as a promising candidate to reduce the requirement for memory bandwidth [1].

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LATHYROIDES, Encoding a WUSCheL-Related Homeoboxl Transcription Factor, Controls Organ Lateral Growth, and Regulates Tendril and Dorsal Petal Identities in Garden Pea （Pisum sativum L.）

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Molecular Plant 2012年第6期5卷 1333-1345页

作者： Li-Li Zhuang Mike Ambrose Catherine Rameau Lin Weng Jun Yang Xiao-he hu Da Luo Xin Li School of Life Science and Biotechnology Shanghai Jiao Tong UniversityShanghai 200240China Department of Crop Genetics John Innes CentreColneyNorwich NR47UHUK Station de Genetique et d'Amelioration des Plantes Institut J.P.BourginUR 254 INRAVersaillesFrance National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChineseAcademy of SciencesShanghai 200032China State Key Laboratory of Biocontrol School of Life SciencesSun Yat-Sen University135 West Xin-gang RoadGuangzhou 510275China

During organ development, many key regulators have been identified in plant genomes, which play a conserved role among plant species to control the organ identities and/or determine the organ size and shape. It is intriguing whether these key regulators can acquire diverse function and be integrated into different molecular pathways among different species, giving rise to the immense diversity of organ forms in nature. In this study, we have characterized and cloned LATHYROIDES （LATH）, a classical locus in pea, whose mutation displays pleiotropic alteration of lateral growth of organs and predominant effects on tendril and dorsal petal development. LATH encodes a WUSCheL-related home- oboxl （WOX1） transcription factor, which has a conserved function in determining organ lateral growth among different plant species. Furthermore, we showed that LATH regulated the expression level of TENDRIL-LESS （TL）, a key factor in the control of tendril development in compound leaf, and LATH genetically interacted with LOBED STANDARD （LST）, a floral dorsal factor, to affect the dorsal petal identity. Thus, LATH plays multiple roles during organ development in pea： it maintains a conserved function controlling organ lateral outgrowth, and modulates organ identities in compound leaf and zygomorphic flower development, respectively. Our data indicated that a key regulator can play important roles in different aspects of organ development and dedicate to the complexity of the molecular mechanism in the control of organ development so as to create distinct organ forms in different species.

关键词： pea LATH LST TL lateral growth organ identity.

Reperfusion of the rat brain tissues following acute ischemia： the correlation among diffusion-weighted imaging, histopathology, and aquaporin-4 expression

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Chinese Medical Journal 2011年第19期124卷 3148-3153页

作者： LU Hong hu hui he Zhan-ping Department of Radiology Affiliated Haikou Hospital of Xiangya School of Medicine Central South University （Haikou Municipal People＇s Hospital） Haikou Hainan 570208 China

Background Although some studies have reported that aquaporin-4 （AQP4） plays a role in the post-ischemic edema formation and diffusion-weighted imaging （DWI）, little is known about the AQP4 expression in stage of the reperfusion following acute cerebral ischemia, as well as the correlation between histopathology and DWl. The aim of the study was to investigate the correlation among DWl, histopathology and the AQP4 expression in the reperfused rat brain tissues following acute *** Seventy Wistar rats were randomly divided into a control group （group A）, and several occluded and reperfusion groups. They had their middle cerebral artery unilaterally occluded （MCAO） for 30 minutes （group B） followed by 30 minutes （group D） or 60 minutes （group E） of reperfusion, or 60 minutes of MCAO （group C） followed by 30 minutes （group F）, or 60 minutes （group G） of reperfusion （n=10 for each group）. All rats underwent DWl *** relative apparent diffusion coefficient （rADC） value of each rat was calculated. All the rats were sacrificed and the cerebral ischemic tissues were examined for histopathology. Real-time fluro-quantitative polymerase chain reaction （RT-PCR） and Western-blotting were performed. The amount of AQP4 mRNA （Ex △△Ct） and AQP4 protein （Q） was statistically analyzed. The correlation between rADC values and AQP4 mRNA expression was analyzed with the Pearson correlation *** In all the reperfusion groups, the areas of hyper-intensity signal in DWl were decreased, and the rADC value increased and the AQP4 expression decreased significantly compared with the occluded group （t=26.89, t=18.26, P〈0.01）. There was a negative correlation between AQP4 mRNA expression and rADC values （r=-0.72, P〈0.01）. A mixed edema, composed of cerebral intracelluar edema and vasogenic brain edema, was observed in all the reperfusion *** was more prevalent in groups D and F than in the groups E and G. With the reperfusion time postponed, the cerebral intracel

关键词： aquaporin-4 magnetic resonance imaging ischemia reperfusion

Comparison of laparoscopic and open surgery for pyogenic liver abscess with biliary pathology

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World Journal of Gastroenterology 2011年第38期17卷 4339-4343页

作者： Jin-Fu Tu Xiu-Fang huang Ru-Ying hu he-Yi You Xiao-Feng Zheng Fei-Zhao Jiang Department of LaparoscopicSurgery the First Affiliated Hospital of Wenzhou Medical Col-lege Wenzhou 325000 Zhejiang Province China

AIM:To investigate the feasibility and therapeutic effect of laparoscopic surgery for pyogenic liver abscess(PLA) with biliary ***:From January 2004 to October 2010,31 patients with PLA combined with biliary pathology meeting entry criteria received surgical management in our *** the 31 patients,13 underwent laparoscopic surgery(LS group) and 18 underwent open surgery(OS group).Clinical data including operation time,intraoperative blood loss,postoperative complication rate,length of postoperative hospital stay,and abscess recurrence rate were retrospectively analyzed and compared between the two ***:All patients received systemic antibiotic *** patients underwent ultrasound-guided percutaneous catheter drainage before *** complications occurred in 5 patients(16.1%,5/31) including 2 in the LS group and 3 in the OS *** patient had retained calculus in the common bile duct and another had liver abscess recurrence in the OS *** retained calculus and liver abscess recurrence occurred in the LS *** the two groups,there was no mortality during the perioperative *** were no significant differences in operation time,intraoperative blood loss and transfusion,postoperative complication rate and abscess recurrence rate between the two *** intake was earlier(1.9 ± 0.4 d vs 3.1 ± 0.7 d,P he LS group than in the OS ***:Laparoscopic surgery for simultaneous treatment of PLA and biliary pathology is feasible in selected patients and the therapeutic effect is similar to that of open surgery.

关键词： Liver abscess Biliary Laparoscopy Surgery Therapeutic effect

Etiological and clinicopathologic characteristics of intrahepatic cholangiocarcinoma in young patients

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World Journal of Gastroenterology 2010年第7期16卷 881-885页

作者： Zhou, hua-Bang Wang, hui Zhou, Dong-Xun Wang, Hao Wang, Qing Zou, Shan-Shan hu, he-Ping Second Mil Med Univ Eastern Hepatobiliary Surg Hosp Dept Comprehens Treatment 2 Shanghai 200438 Peoples R China

AIM:To investigate the prevalence,risk factors,and clinicopathologic characteristics of intrahepatic cholangiocarcinoma(ICC)in young ***:A retrospective analysis was performed in ICC patients referred to the Eastern hepatobiliary Surgery Hospital in Shanghai,*** 317 consecutively enrolled patients,40 patients were aged ≤40 years(12.61%).We compared the risk factors and clinicopathologic characteristics of these patients(groupⅠ:n=40)with those aged>40 years(group Ⅱ:n=277).RESULTS:Group I had distinct features compared with groupⅡ,including a low frequency of hepatolithiasis(P=0.000);a high positive rate of serum hepatitis B surface antigen(P=0.000)and hepatitis B virus(HBV)associated cirrhosis(P=0.038);a high frequency ofα-fetoprotein(>400μg/L)(P=0.011);a low frequency of carbohydrate antigen 19-9(>37 U/mL)(P=0.017);and a high frequency of liver histological inflammation(P=0.002).Although there was no significant difference between the two groups in regards to hepatic schistosomiasis,alcohol-associated cirrhosis and cirrhosis due to other causes(P>0.05),they only occurred in the elderly ***:The risk factors are significantly different between young and elderly ICC *** and HBV-associated cirrhosis are the most important risk factors for young ICC patients.

关键词： Intrahepatic cholangiocarcinoma Young patients Clinicopathologic features hepatitis B virus Risk factor

Blood F_2-isoprostanes are significantly associated with abnormalities of lipid status in rats with steatosis

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World Journal of Gastroenterology 2008年第29期14卷 4677-4683页

作者： Man-Jie Zhu Li-Juan Sun Yue-Qin Liu Yan-Ling Feng Hai-Tao Tong Ying-he hu Zheng Zhao Laboratory of Pharmacology Institute of Brain Functional Genomics East China Normal University Key Laboratory of Brain Functional Genomics MOE & STCSM Shanghai 200062 China Department of Pathology Shanghai Public Health Clinical Center Fudan University Shanghai 201508 China

AIM: To investigate oxidative stress and lipid peroxi-dation in hepatic steatosis and the underlying implica-tions in pathological mechanisms of non-alcoholic fatty liver disease (NAFLD). METHODS: F_2-isoprostanes (iPF2α-) in blood and liver samples from steatotic (n = 9) and control (n = 7) rats were measured as in vivo marker of lipid peroxida-tion by a mass spectrometric approach. The lipid pro-fi le and endogenous antioxidant status (SOD and CAT) in the rats were also analyzed. RESULTS: Signifi cantly higher levels of iPF2α-(mean 3.47 vs 2.40 pmol/mg tissue, P = 0.004) and lower activities of SOD (mean 1.26 U vs 1.40 U, P he livers of steatotic rats. Plasma total iPF2α-was signifi cantly correlated with the abnormalities of blood lipids as well as alanine aminotransferase (ALT) levels in the rats with simple steatosis, whereas no similar tendencies were observed in the control rats. CONCLUSION: Enhancement of hepatic oxidative imbalance occurring at the steatotic stage of NAFLD suggests a possibility that manifestation of the local ⅢⅢⅢoxidative damage precedes that of systemic oxidative imbalance. Predominant metabolic features of the in-creased lipid peroxidation further suggest a close asso-ciation of the oxidative imbalance and the dyslipidemia with functional deterioration of the steatotic liver. The fi ndings need to be further evaluated, especially in hu-man studies.

关键词： Isoprostanes Oxidative stress Lipid per-oxidation Steatosis Non-alcoholic fatty liver disease