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146篇 您的检索式:作者名="David Bell"
    题名 作者 年代 出处 被引量
1可移动机器人的马尔可夫自定位算法研究显示文摘马尔可夫定位算法是利用机器人运动环境中的概率密度分布进行定位的方法 .使用该方法机器人可在完全不知道自己位置的情况下通过传感器数据和运动模型来估计自己的位置 .但是 ,在研究中发现它还存在一些问题 ,如概率减小到零后就无法恢复 .对只有距离传感器的机器人在对称的环境中仅仅采用该算法就无法确定位置 .为了解决这些问题 ,文中给出了修正算法 ,并建议在机器人上装上方向仪 (如指南针或陀螺仪等 ) ,然后利用定义的一个角度高斯分布函数来构造新的机器人感知模型 .在此基础上详细地阐述了一种新的自定位技术 .最后 ,采用仿真程序验证了机器人在对称环境中运动时这一新算法的可行性 .吴庆祥 Bell David 2003自动化学报2003,29,1:15
2Dietary and metabolomic determinants of relapse in ulcerative colitis patients: A pilot prospective cohort study显示文摘AIM To identify demographic, clinical, metabolomic, and lifestyle related predictors of relapse in adult ulcerative colitis(UC) patients.METHODS In this prospective pilot study, UC patients in clinical remission were recruited and followed-up at 12 mo to assess a clinical relapse, or not. At baseline information on demographic and clinical parameters was collected. Serum and urine samples were collected for analysis of metabolomic assays using a combined direct infusion/liquid chromatography tandem mass spectrometry and nuclear magnetic resolution spectroscopy. Stool samples were also collected to measure fecal calprotectin(FCP). Dietary assessment was performed using a validated self-administered food frequency questionnaire. RESULTS Twenty patients were included(mean age: 42.7 ± 14.8 years, females: 55%). Seven patients(35%) experienced a clinical relapse during the follow-up period. While 6 patients(66.7%) with normal body weight developed a clinical relapse, 1 UC patient(9.1%) who was overweight/obese relapsed during the follow-up(P = 0.02). At baseline, poultry intake was significantly higher in patients who were still in remission during follow-up(0.9 oz vs 0.2 oz, P = 0.002). Five patients(71.4%) with FCP > 150 μg/g and 2 patients(15.4%) with normal FCP(≤ 150 μg/g) at baseline relapsed during the follow-up(P = 0.02). Interestingly, baseline urinary and serum metabolomic profiling of UC patients with or without clinical relapse within 12 mo showed a significant difference. The most important metabolites that were responsible for this discrimination were trans-aconitate, cystine and acetamide in urine, and 3-hydroxybutyrate, acetoacetate and acetone in serum. CONCLUSION A combination of baseline dietary intake, fecal calprotectin, and metabolomic factors are associated with risk of UC clinical relapse within 12 mo.Ammar Hassanzadeh Keshtel iFloris F van den Brand Karen L Madsen Rupasri Mandal Rosica ValchevaKaren I Kroeker Beomsoo Han Rhonda C Bell Janis Cole Thomas Hoevers David S Wishart Richard N Fedorak Levinus A Dieleman 2017World Journal of Gastroenterology2017,23,21:9
3时间序列数据分析与预处理显示文摘时间序列分析中常常遇到的一个问题是如何有效地过滤噪音和约简数据 .本文通过修改传统的离散的傅立叶变换来过滤噪音和进行数据的约简 ,并尽可能保留原始时间序列的全局变化趋势 .为检验该方法的有效性 ,本文同时提出一个新颖的数据分类算法MCC ,并用该算法对股票回报率的变化进行预测 ,实验结果显示 ,用MCC算法在预处理后的数据上进行预测 ,其预测的命中率达到 6 3.6 8% ,而在原始数据上进行预测 ,其预测的命中率只有 4 8.98% .显然 ,通过对原始数据进行噪音过滤有效地改善了预测的精度 .另外 ,数据的约简也提高了预测算法的效率 .郭躬德 王晖 David Bell 2003小型微型计算机系统2003,24,12:9
4Efficacy and safety of tenofovir in chronic hepatitis B: Australian real world experience显示文摘AIM To evaluate the long-term treatment outcomes of tenofovir therapy in patients in a real world Australian tertiary care setting.METHODS We performed a retrospective analysis of treatment outcomes among treatment-na?ve and treatment-experienced patients receiving a minimum 3 mo tenofovir therapy through St Vincent's Hospital Melbourne, Australia. We included patients receiving tenofovir [tenofovir disoproxil fumarate(TDF)] monotherapy, as well as patients treated with TDF in combination with a second antiviral agent. Patients were excluded if they demonstrated human immune-deficiency virus/hepatitis C virus/hepatitis delta virus coinfection or were less than 18 years of age. We considered virological and biochemicalresponse, as well as safety outcomes. Virological response was determined by measurement of hepatitis B virus(HBV) DNA using sensitive assays; biochemical response was determined via serum liver function tests; histological response was determined from liver biopsy and fibroscan; safety analysis focused on glomerular renal function and bone mineral density. The primary efficacy endpoint was complete virological suppression over time, defined by HBV DNA < 20 IU/m L. Secondary efficacy endpoints included rates of biochemical response, and HB e antigen(HBe Ag)/HB surface antigen loss and seroconversion over time.RESULTS Ninety-two patients were identified who fulfilled the enrolment criteria. Median follow-up was 26 mo(range 3-114). Mean age was 46(24-78) years, 64(70%) were male and 77(84%) were of Asian origin. 55(60%) patients were treatment-na?ve and 62 patients(67%) were HBe Ag-negative. Complete virological suppression was achieved by 45/65(71%) patients at 12 mo, 37/46(80%) at 24 mo and 25/28(89%) at 36 mo. Partial virological response(HBV DNA 20-2000 IU/m L) was achieved by 89/92(96.7%) of patients. Multivariate analysis showed a significant relationship between virological suppression at end of follow-up and baseline HBV DNA level(OR = 0.897, 95%CI: 0.833-0.967, P = 0.0046) and HBe Ag positive status(OR = 0.373, 95%CI: 0.183-0.762, P = 0.0069). There was no difference in response comparing treatment-na?ve and treatment-experienced patients. Three episodes of virological breakthrough occurred in the setting of noncompliance. Tenofovir therapy was well tolerated.CONCLUSION Tenofovir is an efficacious, safe and well-tolerated treatment in an Australian real-world tertiary care setting. Our data are similar to the reported experience from registration trials.Grace C Lovett Tin Nguyen David M Iser Jacinta A Holmes Robert Chen Barbara Demediuk Gideon Shaw Sally J Bell Paul V Desmond Alexander J Thompson 2017World Journal of Hepatology2017,9,1:7
5Atopic eczema treatment now and in the future:Targeting the skin barrier and key immune mechanisms in human skin显示文摘The skin facilitates a number of key roles but its functioning can be impaired by disease. Atopic eczema is a chronic inflammatory disease where the skin barrier has become leaky, and inflammation occurs. It affects up to 20% of children and 3% of adults worldwide, manifesting as red itchy patches of skin with varying severity. This review aims to investigate the leaky skin barrier and immune mechanisms from the perspective of potential novel treatments. The complexity of atopic eczema as a disease is what makes it difficult to treat. Genome-wide association studies have highlighted possible genetic variations associated with atopic eczema, however in some cases, individuals develop the disease without these genetic risk factors. Loss of function mutations in the filaggrin gene are one of these associations and this is plausible due to its key role in barrier function. The Th2 immune response is the link with regards to the immune mechanisms as atopic inflammation often occurs through increased levels of interleukin(IL)-4 and IL-13. Eczematous inflammation also creates susceptibility to colonisation and damage by bacteria such as Staphylococcus aureus. Potential novel treatments are becoming ever more specific, offering the hope of fewer side effects and better disease control. The best new treatments highlighted in this review target the immune response with human beta defensin 2, phosphodiesterase-4 inhibitors and monoclonal antibodies all showing promise.David C Bell Sara J Brown 2017World Journal of Dermatology2017,6,3:5
6Fungal diversity notes 1–110:taxonomic and phylogenetic contributions to fungal species显示文摘This paper is a compilation of notes on 110 fungal taxa,including one new family,10 new genera,and 76 new species,representing a wide taxonomic and geographic range.The new family,Paradictyoarthriniaceae is introduced based on its distinct lineage in Dothideomycetes and its unique morphology.The family is sister to Biatriosporaceae and Roussoellaceae.The new genera are Allophaeosphaeria(Phaeosphaeriaceae),Amphibambusa(Amphisphaeriaceae),Brunneomycosphaerella(Capnodiales genera incertae cedis),Chaetocapnodium(Capnodiaceae),Flammeascoma(Anteagloniaceae),Multiseptospora(Pleosporales genera incertae cedis),Neogaeumannomyces(Magnaporthaceae),Palmiascoma(Bambusicolaceae),Paralecia(Squamarinaceae)and Sarimanas(Melanommataceae).The newly described species are the Ascomycota Aliquandostipite manochii,Allophaeosphaeria dactylidis,A.muriformia,Alternaria cesenica,Amphibambusa bambusicola,Amphisphaeria sorbi,Annulohypoxylon thailandicum,Atrotorquata spartii,Brunneomycosphaerella laburni,Byssosphaeria musae,Camarosporium aborescentis,C.aureum,C.frutexensis,Chaetocapnodium siamensis,Chaetothyrium agathis,Colletotrichum sedi,Conicomyces pseudotransvaalensis,Cytospora berberidis,C.sibiraeae,Diaporthe thunbergiicola,Diatrype palmicola,Dictyosporium aquaticum,D.meiosporum,D.thailandicum,Didymella cirsii,Dinemasporium nelloi,Flammeascoma bambusae,Kalmusia italica,K.spartii,Keissleriella sparticola,Lauriomyces synnematicus,Leptosphaeria ebuli,Lophiostoma pseudodictyosporium,L.ravennicum,Lophiotrema eburnoides,Montagnula graminicola,Multiseptospora thailandica,Myrothecium macrosporum,Natantispora unipolaris,Neogaeumannomyces bambusicola,Neosetophoma clematidis,N.italica,Oxydothis atypica,Palmiascoma gregariascomum,Paraconiothyrium nelloi,P.thysanolaenae,Paradictyoarthrinium tectonicola,Paralecia pratorum,Paraphaeosphaeria spartii,Pestalotiopsis digitalis,P.dracontomelon,P.italiana,Phaeoisaria pseudoclematidis,Phragmocapnias philippinensis,Pseudocamarosporium cotinae,Pseudocercospora tamarindi,Pseudotrichia rubriostiolata,P.thailandica,Psiloglonium multiseptatum,Saagaromyces mangrovei,Sarimanas pseudofluviatile,S.shirakamiense,Tothia spartii,Trichomerium siamensis,Wojnowicia dactylidicola,W.dactylidis and W.lonicerae.The Basidiomycota Agaricus flavicentrus,A.hanthanaensis,A.parvibicolor,A.sodalis,Cantharellus luteostipitatus,Lactarius atrobrunneus,L.politus,Phylloporia dependens and Russula cortinarioides are also introduced.Epitypifications or reference specimens are designated for Hapalocystis berkeleyi,Meliola tamarindi,Pallidocercospora acaciigena,Phaeosphaeria musae,Plenodomus agnitus,Psiloglonium colihuae,P.sasicola and Zasmidium musae while notes and/or new sequence data are provided for Annulohypoxylon leptascum,A.nitens,A.stygium,Biscogniauxia marginata,Fasciatispora nypae,Hypoxylon fendleri,H.monticulosum,Leptosphaeria doliolum,Microsphaeropsis olivacea,Neomicrothyrium,Paraleptosphaeria nitschkei,Phoma medicaginis and Saccotheciaceae.A full description of each species is provided with light micrographs(or drawings).Molecular data is provided for 90 taxa and used to generate phylogenetic trees to establish a natural classification for species.Jian Kui Liu Kevin D.Hyde E.B.Gareth Jones Hiran A.Ariyawansa Darbhe J.Bhat Saranyaphat Boonmee Sajeewa S.N.Maharachchikumbura Eric H.C.McKenzie Rungtiwa Phookamsak Chayanard Phukhamsakda Belle Damodara Shenoy Mohamed A,Abdel-Wahab Bart Buyck Jie Chen K.W.Thilini Chethana Chonticha Singtripop Dong Qin Dai Yu Cheng Dai Dinushani ADaranagama Asha J.Dissanayake Mingkwan Doilom Melvina J.D’souza Xin Lei Fan Ishani DGoonasekara Kazuyuki Hirayama Sinang Hongsanan Subashini C.Jayasiri Ruvishika S.Jayawardena Samantha C.Karunarathna Wen Jing Li Ausana Mapook Chada Norphanphoun Ka Lai Pang Rekhani H.Perera Derek Peršoh Umpava Pinruan Indunil CSenanayake Sayanh Somrithipol Satinee Suetrong Kazuaki Tanaka Kasun M.Thambugala Qing Tian Saowaluck Tibpromma Danushka Udayanga Nalin N.Wijayawardene Dhanuska Wanasinghe Komsit Wisitrassameewong Xiang Yu Zeng Faten AAbdel-Aziz Slavomir Adamčík Ali H.Bahkali Nattawut Boonyuen Timur Bulgakov Philippe Callac Putarak Chomnunti Katrin Greiner Akira Hashimoto Valerie Hofstetter Ji Chuan Kang David Lewis Xing Hong Li Xing Zhong Liu Zuo Yi Liu Misato Matsumura Peter E.Mortimer Gerhard Rambold Emile Randrianjohany Genki Sato Veera Sri-Indrasutdhi Cheng Ming Tian Annemieke Verbeken Wolfgang von Brackel Yong Wang Ting Chi Wen Jian Chu Xu Ji Ye Yan Rui Lin Zhao Erio Camporesi 2015Fungal Diversity2015,,3:3
7Looking for Loss Aversion in Scanner Panel Data: The Confounding Effect of Price Response Heterogeneity显示文摘David R. Bell James M. Lattin 2000Marketing Science2000,,2:2
8Shopping Behavior and Consumer Preference for Store Price Format: Why “Large Basket” Shoppers Prefer EDLP显示文摘David R. Bell James M. Lattin 1998Marketing Science1998,,1:2
9Managing Software Requirements Changes Based on Negotiation-Style Revision显示文摘For any proposed software project,when the software requirements specification has been established,requirements changes may result in not only a modification of the requirements specification but also a series of modifications of all existing artifacts during the development.Then it is necessary to provide effective and flexible requirements changes management.In this paper,we present an approach to managing requirements changes based on Booth's negotiation-style framework for belief revision.Informally,we consider the current requirements specification as a belief set about the systemto-be.The request of requirements change is viewed as new information about the same system-to-be.Then the process of executing the requirements change is a process of revising beliefs about the system-to-be.We design a family of belief negotiation models appropriate for different processes of requirements revision,including the setting of the request of requirements change being fully accepted,the setting of the current requirements specification being fully preserved,and that of the current specification and the request of requirements change reaching a compromise.In particular,the prioritization of requirements plays an important role in reaching an agreement in each belief negotiation model designed in this paper.牟克典 Weiru Liu 金芝 Jun Hong David Bell 2011Journal of Computer Science & Technology2011,26,5:2
10IL 28 B genotype is not useful for predicting treatment outcome in A sian chronic hepatitis B patients treated with pegylated interferon‐α显示文摘Jacinta A Holmes Tin Nguyen Dilip Ratnam Neel M Heerasing Jane V Tehan Sara Bonanzinga Anouk Dev Sally Bell Stephen Pianko Robert Chen Kumar Visvanathan Rachel Hammond David Iser Ferry Rusli William Sievert Paul V Desmond D Scott Bowden Alexander J Thomps 2013J Gastroenterol Hepatol2013,,5:2
11Long-term outcomes after fractional flow reserve-guided percutaneous coronary intervention in patients with severe coronary stenosis显示文摘Objective To explore the safety and efficacy of FFR-guided percutaneous coronary intervention (PCI) in vessels with severe diameter stenosis. Methods & Results Of 1090 patients undergoing fractional flow reserve (FFR) assessment from 2002 to 2009,we identified 167 patients in whom FFR was measured in at least one 70%–89% stenotic lesion. These patients were subdivided into an FFR-defer group (n = 49) if PCI was deferred (FFR > 0.80),and an FFR-perform group (n = 118) if PCI was performed (FFR ≤ 0.80). Comparatively,an additional 1176 patients undergoing PCI in at least one lesion with 70%–89% stenosis but without measurement of FFR served as a control (angiography- guided) group. Clinical outcomes were compared during a median follow-up of 49.0 months. The 5-year Kaplan-Meier estimated revascularization rates were 16% in the FFR-defer group and 33% in the FFR-perform group (P = 0.046). The incidence of major adverse cardiac events were comparable in these two groups (HR = 0.82,95% CI: 0.37–1.82,P = 0.63). The number of stents placed was significantly lower in the FFR-guided group (0.9 ± 0.8 vs. 1.4 ± 0.8,P < 0.001). Conclusions Functional revascularization for lesions with visually severe stenosis is clinically safe and associated with fewer stents use. This study suggests that extending the use of FFR to more severe coronary lesions may be reasonable.Ying-Hua ZHANG Jing LI Andreas J. Flammer Yoshiki Matsuo Moo-Sik Lee Ryan J. Lennon Malcolm R. Bell David R. Holmes John F. Bresnahan Charanjit S. Rihal Lilach O. Lerman Amir Lerman 2019Journal of Geriatric Cardiology2019,16,4:2
12A Prospective Multicenter Registry of Patients with Chronic Gastroesophageal Reflux Disease Receiving Transoral Incisionless Fundoplication显示文摘Reginald C.W. Bell Peter G. Mavrelis William E. Barnes David Dargis Bart J. Carter Kevin M. Hoddinott Robert W. Sewell Karim S. Trad Brian DaCosta Gill Glenn M. Ihde 2012Journal of the American College of Surgeons2012,,6:2
13SIRT1 regulates differentiation of mesenchymal stem cells by deacetylating β‐catenin显示文摘Petra Simic Kayvan Zainabadi Eric Bell David B. Sykes Borja Saez Sutada Lotinun Roland Baron David Scadden Ernestina Schipani Leonard Guarente 2013EMBO Mol Med2013,,3:2
14Peginterferon and Ribavirin Treatment in African American and Caucasian American Patients With Hepatitis C Genotype 1显示文摘Hari S. Conjeevaram Michael W. Fried Lennox J. Jeffers Norah A. Terrault Thelma E. Wiley–Lucas Nezam Afdhal Robert S. Brown Steven H. Belle Jay H. Hoofnagle David E. Kleiner Charles D. Howell 2006Gastroenterology2006,,2:2
15Effect of oxygen and nitrogen functionalization on the physical and electronic structure of graphene显示文摘graphene 的共有原子价 functionalization 为定制它的性质提供机会并且是一些 graphene 合成技术的不可避免的后果。然而, functionalization 导致的变化很好没被理解。由使用原子来源控制氧和氮 functionalization 的程度,我们在原子规模在结构和性质学习了进化。虽然,原子氧 reversibly 介绍 epoxide 组,在类似的条件下面,原子氮不可逆转地创造包括的多样的功能代理, pyridinic,和 pyrrolic 氮。原子氧在迪拉克点离开费密能量(即, undoped ) ,虽然原子氮导致网做 n;然而,试验性的结果与为两是转变从的主导的电子效果一致去除到局部性的状态,和因此签名的损失 graphene 的电子结构。Alexander J. Marsden Peter Brommer James J. Mudd M. Adam Dyson Robert Cook Maria Asensio Jose Avila Ana Levy Jeremy Sloan David Quigley Gavin R. Bell Neil R. Wilson 2015Nano Research2015,8,8:2
162-year follow-up of trastuzumab after adjuvant chemotherapy in HER2-positive breast cancer: a randomised controlled trial显示文摘Ian Smith Marion Procter Richard D Gelber Sébastien Guillaume Andrea Feyereislova Mitch Dowsett Aron Goldhirsch Michael Untch Gabriella Mariani Jose Baselga Manfred Kaufmann David Cameron Richard Bell Jonas Bergh Robert Coleman Andrew Wardley Nadia Harbec 2007The Lancet2007,,9555:1
17All hyped up and no place to go显示文摘David Bell Jon Binnie Julia Cream Gill Valentine 1994Gender Place & Culture1994,,1:1
18A group cognitive behavior therapy programme with metastatic breast cancier patients显示文摘Sarah Edelaman David R Bell 1999Psycho-ontology1999,8,4:1
19Heart failure : A serious and common comorbidity of diabetes显示文摘David SH Bell MB 2004Clinical Diabetes2004,22,2:1
20Soil Microbial Responses to Temporal Variations of Moisture and Temperature in a Chihuahuan Desert Grassland显示文摘Colin Bell Nancy McIntyre Stephen Cox David Tissue John Zak 2008Microbial Ecology2008,,1:1
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