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Asymptotic energy efficiency analysis for the state-of-the-art relaying protocols

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The Journal of China Universities of Posts and Telecommunications 2011年第6期18卷 8-13页

作者： WANG Yu-ning ZHANG jian-hua xu Wei Key Lab of Universal Wireless Communications Ministry of Education Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

This article analyzes the energy-efficiency performances of fixed relaying schemes, selection relaying schemes and incremental relaying schemes in the three-node relay network. The closed-form asymptotic energy per good-bit （EPG） expressions for the state-of-the-art relaying protocols at high signal-to-noise ratio （SNR） regime are derived. In the formulation of the energy consumption model, the transmission, circuit and retransmission energies are all taken into account. To facilitate the comparison of energy-efficiency performances between different relaying protocols, the link reliabilities and retransmission probabilities are determined by the asymptotic outage probabilities at high SNR regime under the Rayleigh fading assumption. Computer simulations are carried out in both symmetric and asymmetric relay networks. The simulation results show the differences of system energy expenditure between these state-of-the-art relaying protocols. Finally some practical implications can be made from the observation.

关键词： green communication EPG relay energy-efficiency outage probability

Photocatalytic oxidation of primary and secondary benzyl alcohol catalyzed by two coenzyme NAD^+ models

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Chinese Chemical Letters 2007年第12期18卷 1471-1475页

作者： hua jian xu Xiao Lan xu Yao Fu Yi Si Feng School of Chemical Engineering HeFei University of Technology Hefei 230009 China Department of Chemistry AnHui Medical University Hefei 230032 China Department of Chemistry University of Science and Technology of China Hefei 230026 China

Photocatalytic oxidation of primary and secondary benzyl alcohol to corresponding benzaldehyde or acetophenone using Acr＋Cl04- or PhAcr＋Cl04- as photocatalysts under visible light irradiation at room temperature.

关键词： Photocatalyst Coenzyme NAD^+ model Benzyl alcohol Mechanism

Iron-catalyzed selective oxidation of 5-hydroxylmethylfurfural in air:A facile synthesis of 2,5-diformylfuran at room temperature

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Chinese Chemical Letters 2015年第10期26卷 1265-1268页

作者： Chi Fang jian-Jun Dai hua-jian xu Qing-Xiang Guo Yao Fu Anhui Province Key Laboratory of Biomass Clean Energy Department of Chemistry University of Science and Technology of China School of Medical Engineering Hefei University of Technology

An iron（Ⅲ）-catalyzed selective oxidation of 5-HMF to 2,5-DFF in air at room temperature was *** approach gives 2,5-DFF with good selectivity and yields. Additionally, a two-step process was developed for the oxidation of 2,5-DFF to 2,5-FDCA at remarkably high substrate concentrations. This work demonstrates unequivocally the great potential of iron as a cheap and earth-abundant catalyst for the development of new protocols for the conversion of biomass to value-added chemicals.

关键词： Iron Biomass Oxidation Platform molecules Sustainable chemistry

Splenosis masquerading as gastric stromal tumor: A case report

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World Journal of Clinical Cases 2021年第20期9卷 5724-5729页

作者： Hui-Da Zheng jian-hua xu Ya-Feng Sun Department of Gastrointestinal Surgery The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina

BACKGROUND Splenosis is a rare benign disease that often disguises itself as a malignant *** are few articles providing a comprehensive description of splenosis,especially cases located in the stomach being treated by laparoscopic *** SUMMARY A 44-year-old man presented with recurrent upper abdominal pain for more than half a *** patient had splenic rupture caused by trauma more than 10 years ago and underwent *** abdominal contrast-enhanced computed tomography scan revealed an irregular soft tissue *** revealed an approximately 3.0 cm×3.0 cm mucosal eminence at the posterior wall of the upper segment of the gastric *** was not performed since the lesion was found under the mucosa and the gastric mucosa appeared *** to these findings,a diagnosis of gastric stromal tumor was made,although a definitive differential diagnosis was not known before *** laparoscopic resection of the gastric stromal tumor was performed,an astonishing finding was made when postoperative pathology showed that the lesion comprised typical spleen *** This case highlights the strong similarities between splenosis and malignant tumors.A detailed medical history combined with various effective auxiliary examinations can help improve differential diagnosis.

关键词： Splenosis Gastric stromal tumor Laparoscopy Case report

Na-MnO_(x) catalyzed aerobic oxidative cleavage of biomass-derived 1,2-diols to synthesis medium-chain furanic chemicals

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Green Energy & Environment 2022年第5期7卷 957-964页

作者： Qing-Shan Kong Xing-Long Li Hong-Bo Shen hua-jian xu Yao Fu Hefei National Laboratory for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyInstitute of EnergyHefei Comprehensive National Science CenterDepartment of ChemistryUniversity of Science and Technology of ChinaHefei230026China School of Food and Biological Engineering Hefei University of TechnologyHefei230031China Institute of Energy Hefei Comprehensive National Science CenterHefei230009China

Medium-chain furanic chemicals have outstanding practical potential,especially in the application of pharmaceuticals and ***,we describe an eco-friendly and efficient heterogeneous sodium-doped porous sodium manganese oxide catalyst(Na-MnO_(x)) for oxidative cleavage of furanic 1,2-diols into medium-chain furanic aldehyde ***,various high value-added chemicals(diacids and esters,diols,hydroxy acids,acrylics) were synthesized based on the widely applicable and highly selective catalytic *** Na-MnO_(x) was prepared by the coprecipitation method and characterized by XRD,SEM,XPS and FT-IR,and *** revealed that Mn species existed in the mixed oxidation states Mn~Ⅱ,Mn~Ⅲ and Mn~Ⅳ.When NaOH concentration up to 1.8 mol L^(-1) during the preparation process of the catalyst,the ratio of Mn^(4+) in the catalyst was the highest,and the yield of product(Furan-2-acrolein) in the model reaction is also ***,this protocol developed a novel and general route for the preparation of medium-chain furanic compounds utilizing cellulose-derived platform molecules.

关键词： furan oxidative catalyst

Identification of MicroRNA Precursors with Support Vector Machine and String Kernel

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Genomics, Proteomics & Bioinformatics 2008年第2期6卷 121-128页

作者： jian-hua xu Fei Li Qiu-Feng Sun Department of Computer Science Nanjing Normal University Nanjing 210097 China Department ofEntomology Nanjing Agricultural University Nanjing 210095 China

MicroRNAs （miRNAs） are one family of short （21-23 nt） regulatory non-coding RNAs processed from long （70-110 nt） miRNA precursors （pre-miRNAs）. Identifying true and false precursors plays an important role in computational identification of miRNAs. Some numerical features have been extracted from precursor sequences and their secondary structures to suit some classification methods; however, they may lose some usefully discriminative information hidden in sequences and structures. In this study, pre-miRNA sequences and their secondary structures are directly used to construct an exponential kernel based on weighted Levenshtein distance between two sequences. This string kernel is then combined with support vector machine （SVM） for detecting true and false pre-miRNAs. Based on 331 training samples of true and false human pre-miRNAs, 2 key parameters in SVM are selected by 5-fold cross validation and grid search, and 5 realizations with different 5-fold partitions are executed. Among 16 independent test sets from 3 human, 8 animal, 2 plant, 1 virus, and 2 artificially false human pre-miRNAs, our method statistically outperforms the previous SVM-based technique on 11 sets, including 3 human, 7 animal, and 1 false human pre-miRNAs. In particular, premiRNAs with multiple loops that were usually excluded in the previous work are correctly identified in this study with an accuracy of 92.66%.

关键词： string kernel support vector machine microRNA precursor weighted Levenshteindistance

Hepatitis B or C viral infection and risk of pancreatic cancer: A meta-analysis of observational studies

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World Journal of Gastroenterology 2013年第26期19卷 4234-4241页

作者： jian-hua xu Jin-jian Fu Xiao-Li Wang Jia-Yong Zhu Xiao-hua Ye Si-Dong Chen Department of Pathogen Biology School of Public Health and Tropical Medicine Southern Medical University Guangdong Key Laboratory of Molecular Epidemiology School of Public Health Guangdong Pharmaceutical University Institute of Pharmaceutical Bioactive Substances Research Guangdong Pharmaceutical University Department of Clinical Laboratory Guangdong Provincial Hospital of Chinese Medicine Liuzhou Municipal Maternity and Child Healthcare Hospital

AIM: To investigate if there is an association between hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the risk of pancreatic cancer. METHODS: All relevant studies published before 11 October, 2012 were identified by a systematic search of MEDLINE, EMBASE, BIOSIS Previews and the Cochrane Library databases and with cross-referencing. The observational studies that reported RR or OR estimates with 95%CIs for the association between HBV or HCV and pancreatic cancer were included. A random-effects model was used to summarize meta-analytic estimates. The Newcastle-Ottawa quality assessment scale was applied to assess the quality of the methodology in the included studies. RESULTS: A total of 8 eligible studies were selected for meta-analysis. Overall, chronic hepatitis B and inactive hepatitis B surface antigen (HBsAg) carrier state (HBsAg positive) had a significantly increased risk of pancreatic cancer with OR of 1.20 (95%CI: 1.01-1.39), especially in the Chinese population (OR = 1.30, 95%CI: 1.05-1.56). Past exposure to HBV (possible occult HBV infection) had an increased OR of pancreatic cancer risk (OR = 1.24, 95%CI: 1.05-1.42), especially among those patients without natural immunity [anti hepatitis B core (HBc) positive/hepatitis B surface antibody (anti HBs) negative], with OR of 1.67 (95%CI: 1.13-2.22). However, past exposure to HBV with natural immunity (anti-HBc positive/anti-HBs positive) had no association with pancreatic cancer development, with OR 0.98 (95%CI: 0.80-1.16), nor did the HBV active replication (hepatitis B e antigen positive status), with OR 0.98 (95%CI: 0.27-1.68). The risk of pancreatic cancer among anti-HBs positive patients was significantly lower than among anti-HBs negative patients (OR = 0.54, 95%CI: 0.46-0.62). Past exposure to HCV also resulted in an increased risk of pancreatic cancer (OR = 1.26, 95%CI: 1.03-1.50). Significant between-study heterogeneity was observed. Evidence of publication bias for HBV/HCV infecti

关键词： Hepatitis B Hepatitis C Pancreatic cancer Observational studies Meta-analysis

Synthesis of Dendronized Aromatic Polyamides with Chloromethyl Groups in the Periphery by Macromonomer Approach

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Chinese Chemical Letters 2006年第11期17卷 1507-1510页

作者： Mei hua LIU Wei jian xu Xiao Cong xu Yah Bing LU Yah Ru MIAO College of Chemistry ＆ Chemical Engineering Hunan University Changsha 410082

The preliminary results for one-pot synthesis of dendronized aromatic polyamides with chloromethyl groups in the periphery by approach were reported first time. The GPC analysis of the resulting dendronized polymers h... 详细信息

关键词： Macromonomer dendronized functionalized polyamide.

Development and validation of a nomogram for preoperative prediction of tumor deposits in colorectal cancer

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World Journal of Gastroenterology 2023年第39期29卷 5483-5493页

作者： Hui-Da Zheng Yun-huang Hu Kai Ye jian-hua xu Department of Gastrointestinal Surgery The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina

BACKGROUND Based on the clinical data of colorectal cancer(CRC)patients who underwent surgery at our institution,a model for predicting the formation of tumor deposits(TDs)in this patient population was *** To establish an effective model for predicting TD formation,thus enabling clinicians to identify CRC patients at high risk for TDs and implement personalized treatment *** CRC patients(n=645)who met the inclusion criteria were randomly divided into training(n=452)and validation(n=193)cohorts using a 7:3 ratio in this retrospective *** absolute shrinkage and selection operator regression was employed to screen potential risk factors,and multivariable logistic regression analysis was used to identify independent risk ***,a predictive model for TD formation in CRC patients was constructed based on the independent risk *** discrimination ability of the model,its consistency with actual results,and its clinical applicability were evaluated using receiveroperating characteristic curves,area under the curve(AUC),calibration curves,and decision curve analysis(DCA).RESULTS Thirty-four(7.5%)patients with TDs were identified in the training cohort based on postoperative pathological *** logistic regression analysis identified female sex,preoperative intestinal obstruction,left-sided CRC,and lymph node metastasis as independent risk factors for TD *** AUCs of the nomogram models constructed using these variables were 0.839 and 0.853 in the training and validation cohorts,*** calibration curve demonstrated good consistency,and the training cohort DCA yielded a threshold probability of 7%-78%.CONCLUSION This study developed and validated a nomogram with good predictive performance for identifying TDs in CRC *** predictive model can assist surgeons in making optimal treatment decisions.

关键词： Colorectal cancer Tumor deposits Nomogram