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An adaptive random access strategy for multi-channel relaying networks

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Science in China(Series F) 2009年第12期52卷 2406-2414页

作者： JIANG Fan TIAN hui zhang ping Key Laboratory of Universal Wireless Communications Ministry of Education Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

In this paper, an adaptive random access strategy is presented for multi-channel relaying networks to address the issue of random access of the non-real-time （NRT） services. In the proposed scheme, NRT services access the base station （BS） by first accessing the nearest relay node （RN）. When collision occurs, for the sake of fast and efficient access, the user will begin a frequency domain backoff rather than randomly retry in time domain. A remarkable feature of this scheme is that the RN will adaptively determine the maximum allowed frequency backoff window at each access period. This is achieved according to the new arrival rate as well as the number of available access channels. Moreover, to alleviate the interference caused by sub-channel reuse among RNs, a fractional frequency reuse scheme is also considered. The analysis and numerical results demonstrate that our scheme achieves higher throughput, lower collision probability and lower access delay than conventional slotted Aloha as well as the scheme without frequency backoff window adaptation.

关键词： multi-channel relay random access backoff policies interference coordination

A new access scheme in OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 29-33页

作者： GU Xueolin YAN Wei TIAN hui zhang ping Wireless Technology Innovation (WTI) Institute Beijing University of Postsand Telecommunications Beijing 100876 China

This article presents a dynamic random access scheme for orthogonal frequency division multiple access （OFDMA） systems. The key features of the proposed scheme are it is a combination of both the distributed and the centralized schemes, it can accommodate several delay sensitivity classes, and it can adjust the number of random access channels in a media access control （MAC） frame and the access probability according to the outcome of Mobile Terminals access attempts in previous MAC frames. For floating populated packet-based networks, the proposed scheme possibly leads to high average user satisfaction.

关键词： random access scheme RACH OFDMA dynamicaccess probability

Minimum Principle for Plurisubharmonic Functions and Related Topics

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Acta Mathematica Sinica,English Series 2018年第8期34卷 1278-1288页

作者： Fu Sheng DENG hui ping zhang Xiang Yu ZHOU School of Mathematical Sciences University of Chinese Academy of Sciences Beijing 100049 P. R. China Department of Mathematics School of Information Renmin (People's) University of China Beijing 100872 P. R. China Institute of Mathematics AMSS and Hua Loo-Keng Key Laboratory of Mathematics Chinese Academy of Sciences Beijing 100190 P. R. China

This is a survey about some recent developments of the minimum principle for plurisub- harmonic functions and related topics.

关键词： Minimum principle plurisubharmonic functions Stein manifolds geometric invariant the-ory group actions holomorphic vector bundles

Extra-pulmonary tuberculosis infection in the dialysis patients with end stage renal diseases:case reports and literature review

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第1期14卷 76-82页

作者： Wen-fang YANG Fei HAN Xiao-hui zhang ping zhang Jiang-hua CHEN Kidney Disease Center the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

The diagnosis of extra-pulmonary tuberculosis(TB) seems relatively difficult due to the absence of specific symptoms and signs in patients on peritoneal dialysis or *** report four cases of extra-pulmonary tuberculosis on dialysis,with two cases on peritoneal dialysis and two cases on *** presentations,therapy,and outcomes of TB infection in these patients were ***,the English literature published in the PubMed database associating extra-pulmonary tuberculosis on dialysis over the last three decades is reviewed.A total of 61 studies containing 70 cases were *** most common primary disease was diabetic nephropathy(22.86%,16/70).The peritoneum(31.42%,22/70),bone(21.42%,15/70),and lymph node(20%,14/70) were the most frequently *** organ infection was common(90%,63/70).Fever(58.57%,41/70),pain(35.71%,25/70),and enlarged lymph node(20%,14/70) were the most common ***(67.14%,47/70) and culture(40%,28/70) provided most reliable methods for clear diagnosis of *** combined treatment of isoniazid,rifampicin,pyrazinamide,and ethambutol(44.29%,31/70) was the most common *** majority of patients improved(82.86%,58/70);however,12 cases got worse(17.14%),with 10 of them dying(14.29%).Physicians should be aware of the non-specific symptoms and location of infection,and consider tuberculosis in their differential diagnoses in dialysis patients presenting with symptoms such as fever,pain,and weight loss.

关键词： Extra-pulmonary tuberculosis End stage renal disease Dialysis

Fusarielin E,a new antifungal antibiotic from Fusarium sp.

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Chinese Chemical Letters 2007年第8期18卷 954-956页

作者： Yue Gai Ling Ling Zhao Chang Qi Hu hui ping zhang Department of Chemistry of Natural Drugs School of Pharmacy Fudan University Shanghai 200032 China

A new antifungal antibiotic, fusarielin E, was isolated from the marine-derived fungus Fusarium sp. Its structure was established on the basis of various NMR spectroscopic analyses and HR-FAB-MS. Fusarielin E displaye... 详细信息

关键词： Fusarielin E Marine Fungus Pyricularia oryzae

5′-Hydroxyzearalenol,a new β-resorcylic macrolide from Fusarium sp. 05ABR26

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Chinese Chemical Letters 2008年第9期19卷 1089-1092页

作者： Ling Ling Zhao Yue Gai Hisayoshi Kobayashi Chang Qi Hu hui ping zhang Department of Natural Products Chemistry School of Pharmacy Fudan University Shanghai 200032 China Institute of Molecular and Cellular Biosciences The University of Tokyo Tokyo 113-0032 Japan

A new β-resorcylic macrolide, 5＇-hydroxyzearalenol （1）, was isolated from the culture broth of a marine-derived fungus Fusarium sp. 05ABR26. Three known compounds, zearalenone （2）, 8＇-hydroxyzearalenone （3） and zearalenol （4） were also isolated. The structure and relative stereochemistry of 1 were elucidated on the basis of spectroscopic data and single-crystal X-ray diffraction data. Compound 2 displayed potent inhibitory activity against Pyricularia oryzae with a MIC value of 6.25 μg/mL, while compound 3 was much less active; however, 1 and 4 showed no obvious activity.

关键词： 5'-Hydroxyzearalenol Fusarium sp. X-ray diffraction data Pyricularia oryzae

value of contrast-enhanced ultrasound in the differential diagnosis of gallbladder lesion

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World Journal of Gastroenterology 2018年第6期24卷 744-751页

作者： hui-ping zhang Min Bai Ji-Ying Gu Ying-Qian He Xiao-hui Qiao Lian-Fang Du Department of Ultrasound Shanghai General Hospital Shanghai Jiao Tong University School of Medicine

AIM To describe contrast-enhanced ultrasound(CEUS) features and evaluate differential diagnosis value of CEUS and conventional ultrasound for patients with benign and malignant gallbladder lesions. METHODS This study included 105 gallbladder lesions. Before surgical resection and pathological examination, conventional ultrasound and CEUS were performed to examine for lesions. Then, all the lesions were diagnosed as(1) benign,(2) probably benign,(3) probably malignant or(4) malignant using both conventional ultrasound and CEUS. The CEUS features of these gallbladder lesions were analyzed and diagnostic efficiency between conventional ultrasound and CEUS was *** There were total 17 cases of gallbladder cancer and 88 cases of benign lesion. Some gallbladder lesions had typical characteristics on CEUS(e.g., gallbladder adenomyomatosis had typical characteristics of small nonenhanced areas on CEUS). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CEUS were 94.1%, 95.5%, 80.0%, 98.8%and 95.2%, respectively. These were significantly higher than conventional ultrasound(82.4%, 89.8%, 60.9%, 96.3% and 88.6%, respectively). CEUS had an accuracy of 100% for gallbladder sludge and CEUS helped in differential diagnosis among gallbladder polyps, gallbladder adenoma and gallbladder *** CEUS may provide more useful information and improve the diagnosis efficiency for the diagnosis of gallbladder lesions than conventional ultrasound.

关键词： Contrast enhanced ultrasound Conventional ultrasound Gallbladder carcinoma Gallbladder adenomyomatosis

Value of shear wave elastography with maximal elasticity in differentiating benign and malignant solid focal liver lesions

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World Journal of Gastroenterology 2020年第46期26卷 7416-7424页

作者： hui-ping zhang Ji-Ying Gu Min Bai Fan Li Yu-Qing Zhou Lian-Fang Du Department of Ultrasound Shanghai Changning Maternity and Infant Health HospitalEast China Normal UniversityShanghai 200050China Department of Ultrasound Shanghai Fourth People’s HospitalShanghai Tongji University School of MedicineShanghai 200434China Department of Ultrasound Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 200080China

BACKGROUND It is important to differentiate benign and malignant focal liver lesions(FLLs)*** the wide use and acceptance of shear wave elastography(SWE),its value for assessing the elasticity of FLLs and differentiating benign and malignant FLLs is still *** studies of SWE for FLLs used mean elasticity as the parameter to reflect the stiffness of *** the inhomogeneity of tumor stiffness,maximal elasticity(Emax)might be the suitable parameter to reflect the stiffness of FLLs and to differentiate malignant FLLs from benign *** To explore the value of SWE with Emax in differential diagnosis of solid *** We included 104 solid FLLs in 95 patients and 50 healthy *** the subjects were examined using conventional ultrasound(US)and virtual touch tissue quantification(VTQ)imaging.A diagnosis of benign or malignant FLL was made using conventional *** VTQ values were acquired after 10 consecutive measurements for each FLL and each normal liver,and the largest value was recorded as *** There were 56 cases of malignant FLLs and 48 cases of benign FLLs in this *** of malignant FLLs(3.29±0.88 m/s)was significantly higher than that of benign FLLs(1.30±0.46 m/s,P<0.01)and that of livers in healthy volunteers(1.15±0.17 m/s,P<0.01).The cut-off point of Emax was 1.945,and the area under the curve was *** sensitivity and specificity of Emax were 92.9%and 91.7%,respectively,higher(but not significantly)than those of conventional US(80.4%for sensitivity and 81.3%for specificity).Combined diagnosis of conventional US and Emax using parallel testing improved the sensitivity to 100%with specificity of 75%.CONCLUSION SWE is a convenient and easy method to obtain accurate stiffness information of solid *** is useful for differential diagnosis of FLLs,especially in combination with conventional US.

关键词： Focal hepatic lesions Shear wave elastography Conventional ultrasound Maximal elasticity

Differential diagnosis of different types of solid focal liver lesions using two-dimensional shear wave elastography

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World Journal of Gastroenterology 2022年第32期28卷 4715-4724页

作者： Jia Guo Dong Jiang Yi Qian Jiao Yu Yi-Jun Gu Yu-Qing Zhou hui-ping zhang Department of Ultrasound Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Ultrasound Eastern Hepatobiliary Surgery Hospital Affiliated to Naval Medical UniversityShanghai 200433China Department of Infectious Diseases Eastern Hepatobiliary Surgery Hospital Affiliated to Naval Medical UniversityShanghai 200433China Department of Ultrasound Shanghai Changning Maternity and Infant Health HospitalEast China Normal UniversityShanghai 200050China

BACKGROUND The clinical management and prognosis differ between benign and malignant solid focal liver lesions(FLLs),as well as among different pathological types of malignant *** diagnosis of the possible types of solid FLLs is *** previous study confirmed the value of shear wave elastography(SWE)using maximal elasticity(Emax)as the parameter in the differential diagnosis between benign and malignant ***,the value of SWE in the differential diagnosis among different pathological types of malignant FLLs has not been *** To explore the value of two-dimensional SWE(2D-SWE)using Emax in the differential diagnosis of FLLs,especially among different pathological types of malignant *** All the patients enrolled in this study were diagnosed as benign,malignant or undetermined FLLs by conventional *** of FLLs and the periphery of FLLs was measured using 2D-SWE and compared between benign and malignant FLLs or among different pathological types of malignant *** The study included 32 benign FLLs in 31 patients and 100 malignant FLLs in 96 patients,including 16 cholangiocellular carcinomas(CCCs),72 hepatocellular carcinomas(HCCs)and 12 liver ***-five FLLs were diagnosed as undetermined by conventional *** were significant differences between Emax of malignant(2.21±0.57 m/s)and benign(1.59±0.37 m/s)FLLs(P=0.000),and between Emax of the periphery of malignant(1.52±0.39 m/s)and benign(1.36±0.44 m/s)FLLs(P=0.040).Emax of liver metastases(2.73±0.99 m/s)was significantly higher than that of CCCs(2.14±0.34 m/s)and HCCs(2.14±0.46 m/s)(P=0.002).The sensitivity,specificity and accuracy were 71.00%,84.38%and 74.24%respectively,using Emax>1.905 m/s(AUC 0.843)to diagnose as malignant and 23 of 35(65.74%)FLLs with undetermined diagnosis by conventional ultrasound were diagnosed *** Malignant FLLs were stiffer than benign ones and liver metastases were stiffer than primary liver carc

关键词： Focal liver lesions Conventional ultrasound Two-dimensional shear wave elastography Differential diagnosis