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Document Clustering method Based on Frequent Co-occurring Words

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Document Clustering Method Based on Frequent Co-occurring Wo...

Comparison between empirical prokinetics, Helicobacter test-and-treat and empirical endoscopy in primary-care patients presenting with dyspepsia: A one-year study

第20届亚太地区语言、信息和计算国际会议

作者： benjamin C.m.Fung School of Computing Science Simon Fraser University BC Canada V5A 1S6

This paper presents a new document clustering method based on frequent co-occurring words. We first employ the Singular Value Decomposition, and then group the words into clusters called word representatives as substitution of the corresponding words in the original documents. Next, we extract the frequent word representative sets by Apriori. Subsequently, each document is designated to a basic unit described by the frequent word representative set, from which we can get the ultimate clusters by hierarchical clustering. The major advantage of our method is that it can produce the cluster description by the frequent word representatives and then by the corresponding words in the clustering process without any extra works. Compared with the state-of-the-art UPGmA method on benchmark datasets, our method has better performance in terms of the entropy and cluster purity.

关键词： document clustering, text clustering, frequent itemsets. Apriori.

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World Journal of Gastroenterology 2006年第31期12卷 5010-5016页

作者： Wayne HC Hu SK Lam Cindy LK Lam Wm Wong KF Lam KC Lai YH Wong benjamin CY Wong Annie OO Chan CK Chan Gabriel m Leung Wm Hui Department of medicine University of Hong Kong Hong Kong China Department of Statistics and Actuarial Science University of Hong Kong Hong Kong China Department of Community medicine University of Hong Kong Hong Kong China

AIm： To investigate the optimal strategy to treat dyspeptic patients in primary care. mETHODS： Dyspeptic patients presenting to primary care outpatient clinics were randomly assigned to- （1） empirical endoscopy, （2） H pylori test-and-treat, and （3） empirical prokinetic treatment with cisapride. Early endoscopy was arranged if patients remained symptomatic after 2 wk. Symptom severity, quality-of-life （SF-36） as well as patient preference and satisfaction were assessed. All patients underwent endoscopy by wk 6. Patients were followed up for one year. RESULTS： Two hundred and thirty four patients were recruited （163 female, mean age 49）. 46% were H pylori positive. 26% of H pylori tested and 25% of empirical prokinetic patients showed no improvement at wk 2 follow-up and needed early endoscopy. 15% of patients receiving empirical cisapride responded well to treatment but peptic ulcer was the final diagnosis. Symptom resolution and quality-of-life were similar among the groups. Costs for the three strategies were HK$4343, $1771 and $1750 per patient. 66% of the patients preferred to have early endoscopy. CONCLUSION： The three strategies are equally effective. Empirical prokinetic treatment was the least expensive but peptic ulcers may be missed with this treatment. The H pylori test-and-treat was the most cost-effective option .

关键词： Empirical endoscopy Dyspeptic patients Hpylori test-and treat

Switchgrass Biochar Effects on Plant Biomass and microbial Dynamics in Two Soils from Different Regions

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Pedosphere 2015年第3期25卷 329-342页

作者： Charlene N.KELLY Francisco C.CALDERóN Verónica ACOSTA-mARTíNEZ maysoon m.mIKHA Joseph benjamin David W.RUTHERFORD Colleen E.ROSTAD Western Carolina University Department of Geosciences and Natural Resources331 Stillwell HallCullowheeNC 28723 (USA) U.S.Geological Survey Denver CO 80225 (USA) USDA-ARS Akron CO 80720 (USA) USDA-ARS Lubbock TX 79403 (USA)

Biochar amendments to soils may alter soil function and fertility in various ways, including through induced changes in the microbial community. We assessed microbial activity and community composition of two distinct clayey soil types, an Aridisol from Colorado （CO） in the U.S. Central Great Plains, and an Alfisol from Virginia （VA） in the southeastern USA following the application of switchgrass （Panicum virgatum） biochar. The switchgrass biochar was applied at four levels, 0%,0, 2.5%, 5%, and 10%, approximately equivalent to biochar additions of 0, 25, 50, and 100 t ha^-1, respectively, to the soils grown with wheat （Triticum aestivum） in an eight-week growth chamber experiment. We measured wheat shoot biomass and nitrogen （N） content and soil nutrient availability and N mineralization rates, and characterized the microbial fatty acid methyl ester （FAmE） profiles of the soils. Net N mineralization rates decreased in both soils in proportion to an increase in biochar levels, but the effect was more marked in the VA soil, where net N mineralization decreased from -2.1 to -38.4 mg kg^-1. The 10% biochar addition increased soil pH, electrical conductivity, mehlich- and bicarbonate-extractable phosphorus （P）, and extractable potassium （K） in both soil types. The wheat shoot biomass decreased from 17.7 to 9.1 g with incremental additions of biochar in the CO soil, but no difference was noted in plants grown in the VA soil. The FAmE recovery assay indicated that the switchgrass biochar addition could introduce artifacts in analysis, so the results needed to be interpreted with caution. Non-corrected total FAmE concentrations indicated a decline by 457o and 34% with 10% biochar addition in the CO and VA soils, respectively, though these differences became nonsignificant when the extraction efficiency correction factor was applied. A significant decline in the fungi：bacteria ratio was still evident upon correction in the CO soil with biochar. Switchgrass biochar had the p

关键词： correction factor extraction efficiency fatty acid methyl ester profile nitrogen mineralization soil microbial community soil nutrient availability wheat

维普期刊数据库

A prospective longitudinal study shows putamen volume is associated with moderate amphetamine use and resultant cognitive impairments

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Psychoradiology 2021年第1期1卷 3-12页

作者： Keith m.Kendrick Joerg Daumann Daniel Wagner Philip Koester marc Tittgemeyer Qiang Luo Euphrosyne Gouzoulis-mayfrank benjamin Becker The Clinical Hospital of Chengdu Brain Science Institute Key Laboratory for NeuroinformationCenter for Information in MedicineSchool of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengduChina Department of Psychiatry and Psychotherapy University of CologneGermany max-Planck Institute for Neurological Research CologneGermany Institute of Science and Technology for Brain-Inspired Intelligence Ministry of Education Key Laboratory of Computational Neuroscience and Brain-Inspired IntelligenceFudan UniversityShanghaiPR China LVR Clinics of Cologne CologneGermany

Background:Amphetamine-type stimulants(ATS)have become a critical public health *** models have indicated a clear neurotoxic potential of *** humans,chronic use has been associated with cogni-tive deficits and structural brain ***,cross-sectional retrospective designs in chronic users cannot truly determine the causal direction of the ***:To prospectively determine effects of occasional ATS use on cognitive functioning and brain ***:In a prospective longitudinal study design,cognitive functioning and brain structure were assessed at baseline and at 12-month follow-up in occasional ATS users(cumulative lifetime usemination of change scores between the initial examination and follow-up revealed declined verbal memory performance and putamen volume in users with high relative to low interim ATS *** the entire sample,interim ATS use,memory decline,and putamen volume reductions were strongly ***:The present findings support the hypothesis that ATS use is associated with deficient dorsal stri-atal morphology that might reflect alterations in dopaminergic *** importantly,these findings strongly suggest that even occasional,low-dose ATS use disrupts striatal integrity and cognitive functioning.

关键词： amphetamines brain volume dorsal striatum mDmA prospective stimulants

In vivo and ex vivo confocal endomicroscopy of pancreatic cystic lesions: A prospective study

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World Journal of Gastroenterology 2017年第18期23卷 3338-3348页

作者： Somashekar G Krishna Rohan m modi Amrit K Kamboj benjamin J Swanson Phil A Hart mary E Dillhoff Andrei manilchuk Carl R Schmidt Darwin L Conwell Division of Gastroenterology Hepatology and NutritionThe Ohio State University Wexner Medical Center Department of Internal medicine The Ohio State University Wexner Medical Center College of medicine The Ohio State University Wexner Medical Center Department of Pathology The Ohio State University Wexner Medical Center Division of Surgical Oncology The Ohio State University Wexner Medical Center Deparment of General Surgery The Ohio State University Wexner Medical Center

To investigate the reproducibility of the in vivo endoscopic ultrasound (EUS) - guided needle based confocal endomicroscopy (nCLE) image patterns in an ex vivo setting and compare these to surgical histopathology for characterizing pancreatic cystic lesions (PCLs).mETHODSIn a prospective study evaluating EUS-nCLE for evaluation of PCLs, 10 subjects underwent an in vivo nCLE (AQ-Flex nCLE miniprobe; Cellvizio, maunaKea, Paris, France) during EUS and ex vivo probe based CLE (pCLE) of the PCL (Gastroflex ultrahigh definition probe, Cellvizio) after surgical resection. Biopsies were obtained from ex vivo CLE-imaged areas for comparative histopathology. All subjects received intravenous fluorescein prior to EUS and pancreatic surgery for in vivo and ex vivo CLE imaging *** total of 10 subjects (mean age 53 ± 12 years; 5 female) with a mean PCL size of 34.8 ± 14.3 mm were enrolled. Surgical histopathology confirmed 2 intraductal papillary mucinous neoplasms (IPmNs), 3 mucinous cystic neoplasms (mCNs), 2 cystic neuroendocrine tumors (cystic-NETs), 1 serous cystadenoma (SCA), and 2 squamous lined PCLs. Characteristic in vivo nCLE image patterns included papillary projections for IPmNs, horizon-type epithelial bands for mCNs, nests and trabeculae of cells for cystic-NETs, and a “fern pattern” of vascularity for SCA. Identical image patterns were observed during ex vivo pCLE imaging of the surgically resected PCLs. Both in vivo and ex vivo CLE imaging findings correlated with surgical *** vivo nCLE patterns are reproducible in ex vivo pCLE for all major neoplastic PCLs. These findings add further support the application of EUS-nCLE as an imaging biomarker in the diagnosis of PCLs.

关键词： Confocal laser endomicroscopy Serous cystadenoma Pancreatic neuroendocrine tumor Intraductal papillary mucinous neoplasm Pancreatic cystic neoplasm

Necklaces of PT-symmetric dimers

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Photonics Research 2018年第5期6卷 I0012-I0018页

作者： D.J.NODAL STEVENS benjamin JARAmILLO AVILA B.m.RODRIGUEZ-LARA Tecnologico de monterrey Escuela de Ingenieria y CienciasAve.Eugenio Garza Sada 2501MonterreyN.L.64849Mexico CONACYT-Instituto Nacional de Astroffsica Optica y ElectronicaCalle Luis Enrique Erro No.1Sta.Ma.TonantzintlaPue.CP 72840Mexico Instituto Nacional de Astroffsica Optica y ElectronicaCalle Luis Enrique Erro No.1Sta.Ma.TonantzintlaPue.CP 72840Mexico

We study light propagation through cyclic arrays, composed by copies of a given PT-symmetric dimer, using a group theoretical approach and finite dement modeling. The theoretical mode-coupling analysis suggests the use of these devices as output port replicators where the dynamics is controlled by the impinging light field. This is confirmed in good agreement with finite element propagation in an experimentally feasible necklace of passive PT-symmetric dimers constructed from lossy and lossless waveguides.

关键词： Necklaces PT-symmetric dimers

维普期刊数据库

孤啡肽、内吗啡肽-1和-2与无脊椎动物免疫和神经系统的μ3阿片受体无相互作用（英文）

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Acta Pharmacologica Sinica 2000年第6期21卷 38-42页

作者： Christos m RIALAS,benjamin WEEKS,Patrick CADET,Yannick GOUmON,George B STEFANO Neuroscience Research Institute State University of New York at Old Westbury Old Westbury NY 11568-0210 USA Biology Department Adelphi University Garden City New York 11530 USA Neuroscience Research Institute State University of New York at Old Westbury Old Westbury NY 11568-0210 USA Neuroscience Research Institute State University of New York at Old Westbury Old Westbury NY 11568-0210 USA Biology Department Adelphi University Garden City New York 11530 USA Neuroscience Research Institute NY 11568-0210 USA

AIm: To determine if endomorphin-1,-2 and nociceptin (orphanin FQ) bind to the μ3 opiate receptor subtype or release nitric oxide as μ3 selective ligands do. mETHODS: These opioid peptides were examined for their ability to displace [3H]dihydromorphine (DHm) binding from the invertebrate (immunocytes and pedal ganglia)μ3 opiate receptor in membrane homogenates. The ligands were also tested for their ability to release nitric oxide from the same intact tissues utilizing an amperometric probe that measures nitric oxide in real-time. RESULTS: Endomorphin-1,-2 and nociceptin do not displace [3H]DHm binding from immunocyte or pedal ganglia membrane homogenates nor do they release nitric oxide from these tissues. CONCLUSION: Since these newly discovered opioid peptides do not interact with the μ3 opiate receptor subtype, endogenous morphine' s significance is enhanced because it appears to be the only naturally occurring opiate ligand for the receptor. Furthermore, since this study involves invertebrate t

关键词：阿片样肽类吗啡一氧化氮贻贝免疫细胞 mu阿片受体

Frequency of typhoon occurrence accounts for the Poisson distribution of human leptospirosis cases across the different geographic regions in the Philippines

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Asian Pacific Journal of Tropical medicine 2019年第1期12卷 38-42页

作者： Derick Erl P.Sumalapao benjamin Kyle m.Del Rosario Lara Beatrice L.Su?ga Catherine C.Walthern Nina G.Gloriani Department of medical microbiology College of Public Health University of the Philippines Manila Department of Biology College of Science De La Salle University Senior High School Department De La Salle University

Objective: To study the distribution of human leptospirosis cases across the different geographic regions in the Philippines in 2015-2017 and to determine the relationship between the frequency of typhoon occurrence and human leptospirosis cases. methods: Information on the frequency of leptospirosis cases and typhoon occurrence across the different regions in the Philippines from 2015 to 2017 was retrieved from the databases of the Department of Health and the Philippine Atmospheric, Geophysical, and Astronomical Services Administration, respectively. Descriptive measures on the prevalent cases and occurrence of typhoons across the different regions were summarized. Linear regression analysis was employed to establish the functional relationship between leptospirosis cases and typhoon occurrence. The distribution of human leptospirosis cases was assessed using the Poisson distribution. Results: The frequency of typhoon occurrence accounted for the significant linear variation in the geographic distribution of human leptospirosis cases in the Philippines(Pmoreover, the human leptospirosis cases obeyed a Poisson distribution(λ=6.89, Pmitting bacterial infections including leptospirosis. Information obtained regarding the determinants and distribution of human leptospirosis will provide better understanding of the disease propagation for subsequent design of optimal disease prevention measures, appropriate resource allocation, effective control strategies, and necessary public health programs.

关键词： Human leptospirosis Typhoon Poisson distribution Philippines

mechanisms of biliary carcinogenesis and growth

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World Journal of Gastroenterology 2008年第19期14卷 2986-2989页

作者： Candace Wise metaneeya Pilanthananond benjamin F Perry Gianfranco Alpini michael mcNeal Shannon S Glaser Systems Biology and Translational medicine Scott and White Hospital and The Texas A&M University System Health Science Center Department of medicine Scott and White Hospital and The Texas A&M University System Health Science Center The Texas A&m University System Health Science Center

Cholangiocarcinoma is a rare cancer originating from the neoplastic transformation of the epithelial cells (i.e. cholangiocytes) that line the biliary tract. The prognosis for patients with cholangiocarcinoma is grim due to lack of viable treatment options. The increase in world-wide incidence and mortality from cholangiocarcinoma highlights the importance of understanding the intracellular mechanisms that trigger the neoplastic transformation of cholangiocytes and the growth of biliary cancers. The purpose of the following review is to address what has been learned over the past decade concerning the molecular basis of cholangiocarcinogenesis. The material presented is divided into two sections:(1) mechanisms regulating neoplastic transformation of cholangiocytes; and (2) factors regulating cholangiocarcinoma growth. An understanding of the growth regulatory mechanisms of cholangiocarcinoma will lead to the identification of therapeutic targets for this devastating cancer.

关键词： Biliary carcinogenesis Cholangiocarcinomas Primary biliary cirrhosis Primary sclerosing cholangitis