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Dunkl's Theory and Best Approximation by Entire Functions of Exponential Type in L_2-metric with Power Weight

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Acta Mathematica Sinica,English Series 2014年第10期30卷 1748-1762页

作者： yong Ping LIU Chun Yuan SONG School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education

In this paper, we study the sharp Jackson inequality for the best approximation of f ∈L2,k（Rd） by a subspace Ek2（σ）（sek2（σ））, which is a subspace of entire functions of exponential type （spherical exponential type） at most σ. Here L2,k（Rd） denotes the space of all d-variate functions f endowed with the L2-norm with the weight vk（x）=Пζ∈R＋}（ζ,x）}2k（ζ）,which is defined by a positive subsystem R＋ of a finite root system R Rd and a function k（ζ）：R→R＋ invariant under the reflection group G（R） generated by R. In the case G（R） = Z2d, we get some exact results. Moreover, the deviation of best approximation by the subspace Ek2（σ）（SE2（σ）） of some class of the smooth functions in the space L2,k（Rd） is obtained.

关键词： Reflection group Dunkl transform Bessel function Jackson inequality continuous modulus

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P2P信息检索及其优化策略

计算机科学 2006年第8期33卷 173-177页

作者：凌波吕永成周水庚周傲英 Ng wee Siong 中国浦东干部学院信息技术部上海201204 广西大学信息与系统工程研究所南宁530005 复旦大学计算机科学与工程系上海200433 新加坡国立大学计算机学院新加坡117543

本文研究对等计算(P2P)环境中语义丰富的信息检索及其优化策略,提出了P2P信息检索系统(PIRS),实现了P2P环境中语义丰富的信息检索,定义了一套评价PIRS效率的指标体系;明确了决定PIRS效率的关键因素并提出相应的解决策略,包括:基于向量... 详细信息

本文研究对等计算(P2P)环境中语义丰富的信息检索及其优化策略,提出了P2P信息检索系统(PIRS),实现了P2P环境中语义丰富的信息检索,定义了一套评价PIRS效率的指标体系;明确了决定PIRS效率的关键因素并提出相应的解决策略,包括:基于向量空间模型的节点数据分类管理策略、基于节点聚类的系统数据管理策略以及自适应查询路由策略,并用实验结果验证了这些策略的有效性。

关键词：对等计算信息检索优化策略

Analysis of Micro-scale Flame Structure of AP/HTPB Base Bleed Propellant Combustion

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Defence Technology（防务技术） 2013年第4期9卷 217-223页

作者： Rui YE yong-gang YU yong-jie CAO School of Energy and Power Engineering Nanjing University of Science and Technology

A complex multiple flame structure is formed during the combustion of AP/HTPB base bleed *** AP monopropellant flame is concentrated in a thin zone above the burning surface of AP crystal to maintain self-sustained *** to the low temperature near the burning surface,the diffusion between the decomposition products of AP and the pyrolysis products of HTPB occurs,and a partly pre-mixed diffusion flame structure-leading edge flame(LEF)is *** effects of pressure,chemical reaction rate and AP particle size on diffusion flame structure in the range from 20 atm to 100 atm are *** Peclet number increases from 6.64 at 20 atm to 21.91 at 100 atm when AP particle size is 140 *** high temperature zone is blown away from the burning surface because the convective transport rate increases with the increase in Peclet *** chemical reaction rate is enhanced and the diffusion mixing is inhibited as Damkohler number *** chemical heat release is more concentrated and the chemical reaction zone becomes narrow when Damkohler number changes from 330 at20 atm to 4700 at 100 *** AP particle diameter is decreased to 60 mm,the diffusion time scale is reduced due to the reduced diffusion length *** the diffusion mixing is enhanced and a more pre-mixed flame is *** burning rate increases because the more pre-mixed heat release increases the heat feedback to the HTPB binder.

关键词：推进剂燃烧火焰结构 HTPB 结构分析 AP 底排化学反应速率 Peclet数

Is there an association between Helicobacter pylori infection and irritable bowel syndrome? A meta-analysis

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World Journal of Gastroenterology 2019年第37期25卷 5702-5710页

作者： Qin Xiang Ng Nadine Xinhui Foo Wayren Loke Yun Qing Koh Vanessa Jing Min Seah Alex Yu Sen Soh wee Song Yeo Medicine MOH Holdings Pte LtdSingapore 099253Singapore General and Community Psychiatry Institute of Mental HealthSingapore 117597Singapore Department of General Medicine Tan Tock Seng Hospital11 Jalan Tan Tock SengSingapore 308433Singapore Department of Gastroenterology and Hepatology National University HospitalNational University Health SystemSingapore 119074Singapore yong Loo Lin School of Medicine National University of SingaporeSingapore 117597Singapore

BACKGROUND Irritable bowel syndrome(IBS)is a prevalent and debilitating gastrointestinal *** has reported persistent,low-grade mucosal inflammation and significant overlaps between patients with IBS and those with dyspepsia,suggesting a possible pathogenic role of Helicobacter pylori(***)in *** study therefore aimed to provide the first systematic review and meta-analysis on the association between *** infection and *** To investigate the association between *** infection and *** Using the keywords“*** OR Helicobacter OR Helicobacter pylori OR infection”AND“irritable bowel syndrome OR IBS”,a preliminary search of PubMed,Medline,Embase,Cochrane Database of Systematic Reviews,Web of Science,Google Scholar and WanFang databases yielded 2924 papers published in English between 1 January 1960 and 1 June *** were also made to search grey *** A total of 13 clinical studies were systematically reviewed and nine studies were included in the final ***-effects meta-analysis found a slight increased likelihood of *** infection in patients with IBS,albeit this was not statistically significant(pooled odds ratio 1.47,95%confidence interval:0.90-2.40,P=0.123).It must also be acknowledged that all of the available studies reported only crude odd *** eradication therapy also does not appear to improve IBS *** publication bias was not observed in the funnel plot,there was a high degree of heterogeneity amongst the studies included in the meta-analysis(I2=87.38%).CONCLUSION Overall,current evidence does not support an association between IBS and *** *** rigorous and detailed studies with larger sample sizes and after *** eradication therapy are warranted.

关键词： Irritable bowel syndrome Functional Helicobacter pylori Infection Metaanalysis

Novel mechanism of drug resistance to proteasome inhibitors in multiple myeloma

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World Journal of Clinical Oncology 2019年第9期10卷 303-306页

作者： Jianbiao Zhou wee-Joo Chng Cancer Science Institute of Singapore National University of SingaporeCentre for Translational MedicineSingapore 117599Singapore Department of Medicine Yong Loo Lin School of MedicineNational University of SingaporeSingapore 119074Singapore Department of Hematology-Oncology National University Cancer InstituteNUHSSingapore 119228Singapore

Multiple myeloma(MM) is a cancer caused by uncontrolled proliferation of antibody-secreting plasma cells in bone marrow, which represents the second most common hematological malignancy. MM is a highly heterogeneous disease and can be classified into a spectrum of subgroups based on their molecular and cytogenetic abnormalities. In the past decade, novel therapies, especially, the first-in-class proteasome inhibitor bortezomib, have been revolutionary for the treatment of MM patients. Despite these remarkable achievements, myeloma remains incurable with a high frequency of patients suffering from a relapse, due to drug resistance. Mutation in the proteasome β5-subunit(PSMB5) was found in a bortezomib-resistant cell line generated via long-term coculture with increasing concentrations of bortezomib in 2008, but their actual implication in drug resistance in the clinic has not been reported until recently. A recent study discovered four resistance-inducing PSMB5 mutations from a relapsed MM patient receiving prolonged bortezomib treatment. Analysis of the dynamic clonal evolution revealed that two subclones existed at the onset of disease, while the other two subclones were induced. Protein structural modeling and functional assays demonstrated that all four mutations impaired the binding of bortezomib to the 20 S proteasome, conferring different degrees of resistance. The authors further demonstrated two potential approaches to overcome drug resistance by using combination therapy for targeting proteolysis machinery independent of the 20 S proteasome.

关键词： Multiple myeloma Proteasome inhibitor Bortezomib Proteasome β5-subunit Drug resistance Clonal evolution Combination therapy

NF-κB promotes the stem-like properties of leukemia cells by activation of LIN28B

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World Journal of Stem Cells 2018年第4期10卷 34-42页

作者： Jianbiao Zhou Jing-Yuan Chooi Ying Qing Ching Jessie Yiying Quah Sabrina Hui-Min Toh Yvonne Ng Tuan Zea Tan wee-Joo Chng Cancer Science Institute of Singapore National University of Singapore Department of Medicine Yong Loo Lin School of MedicineNational University of Singapore Department of Hematology-Oncology National University Cancer Institute

AIM To examine whether nuclear factor kappa B(NF-κB) activity regulates LIN28 B expression and their roles in leukemia stem cell(LSC)-like properties. METHODS We used pharmacological inhibitor and cell viability assays to examine the relation between NF-κB and LIN28 B. Western blot and q RT-PCR was employed to determine their protein and m RNA levels. Luciferase reporter was constructed and applied to explore the transcriptional regulation of LIN28 B. We manipulated LIN28 B level in acute myeloid leukemia(AML) cells and investigated LSC-like properties with colony forming and serial replating assays. RESULTS This study revealed the relationship between NF-κB and LIN28 B in AML cells through drug inhibition and overexpression experiments. Notably,inhibition of NF-κB by pharmacological inhibitors reduced LIN28 B expression and decreased cell proliferation. We demonstrated that NF-κB binds to the-819 to-811 region of LIN28 B promoter,and transcriptionally regulates LIN28 B expression. LIN28 B protein was significantly elevated in NFκB1 transfected cells compared to vector control. Importantly,ectopic expression of LIN28 B partially rescued the self-renewal capacity impaired by pharmacological inhibition of NF-κB activity. CONCLUSION These results uncover a regulatory signaling,NF-κB/LIN28 B,which plays a pivotal role in leukemia stem cell-like properties and it could serve as a promising intervening target for effective treatment of AML disease.

关键词： Nuclear factor kappa B LIN28B Leukemia stem cell Acute myeloid leukemia

新加坡的生活方式和饮食习惯与鼻咽癌风险的关系:一项病例对照研究

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癌症 2018年第11期37卷 502-510页

作者： Sook Kwin yong Tam Cam Ha Ming Chert Richard Yeo Valerie Gaborieau James D.McKay Joseph wee Division of Clinical Trials and Epidemiological Sciences National Cancer Centre Singapore Medical Education Research & Evaluation Department (MERE) Duke-NUS Medical School Division of Radiation Oncology National Cancer Centre Singapore Genetic Cancer Susceptibility Group International Agency for Research on Cancer World Health Organization

背景与目的鼻咽癌(nasopharyngeal carcinoma,NPC)是东南亚地区一种常见的癌症。许多研究已经对NPC的风险因素进行了研究,但一些风险因素的作用仍无定论。本研究旨在探讨新加坡人可改变的生活方式因素与NPC风险之间的关系。方法我们在... 详细信息

背景与目的鼻咽癌(nasopharyngeal carcinoma,NPC)是东南亚地区一种常见的癌症。许多研究已经对NPC的风险因素进行了研究,但一些风险因素的作用仍无定论。本研究旨在探讨新加坡人可改变的生活方式因素与NPC风险之间的关系。方法我们在新加坡进行了一项病例对照研究,在2008年至2012年期间招募了300例患者和310例对照。根据性别、种族和年龄(±5岁)对各例对照进行选择并分别与每一例患者匹配。共有290对病例和对照成功匹配。我们对多个生活方式因素,如吸烟、饮酒、各种腌制和罐头食品消费以及断奶习惯进行了研究。结果调整协变量后多因素分析显示,现行吸烟者和有既往吸烟史的参与者比从未吸烟的参与者患NPC的风险更高,优势比(odds ratios,ORs)分别为4.50 [95%置信区间(confidence interval,CI):2.58–7.86;P <0.001]和2.52(95%CI:1.54–4.12;P <0.001)。每周至少吃1次腌制蔬菜的人也比那些从不或很少食用腌制蔬菜的人表现出NPC风险显著增加,OR值为4.18(95%CI:1.69–10.38;P=0.002)。结论吸烟(现行和经常吸食)和每周1次或多次食用腌制蔬菜是NPC的生活方式风险因素,戒除这些不良因素可以降低NPC的风险。

关键词：鼻咽癌饮食吸烟饮酒病例对照研究罐头食品

Histopathological Features Predicting Long-term Clinical Outcomes in Patients with Vanishing Bile Duct Syndrome

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Journal of Clinical and Translational Hepatology 2023年第5期11卷 1161-1169页

作者： Tingting Lv Haitian Yu Xiao Han Aileen wee Jimin Liu Min Li Jinghang Xu Xiaoli Hu Jia Li Weijia Duan Tailing Wang Jidong Jia Xinyan Zhao Liver Research Center Beijing Friendship HospitalCapital Medical UniversityNational Clinical Research Center for Digestive DiseasesBeijingChina Department of Pathology Yong Loo Lin School of MedicineNational University of SingaporeNational University HospitalSingapore Department of Pathology and Molecular Medicine Faculty of Health SciencesMcMaster UniversityHamiltonOntarioCanada Clinical Epidemiology and Evidence-Based Medicine Unit National Clinical Research Center for Digestive DiseasesBeijing Friendship HospitalCapital Medical UniversityBeijingChina Department of infectious disease Peking University First HospitalBeijingChina Department of infectious disease Heilongjiang Province HospitalHeilongjiangChina Department of Hepatology Tianjin Second People’s HospitalTianjinChina Department of Pathology China-Japan Friendship HospitalBeijingChina

Background and Aims:The clinicopathological features and long-term outcomes of patients with vanishing bile duct syndrome(VBDS)have yet to be *** study aims to investigate these features and identify factors associated with poor ***:This multicenter retrospective study recruited patients with liver biopsy-proven VBDS who were followed up at five hospitals in northern China from January 2003 to April *** and pathological data at time of biopsy were *** outcomes including cirrhosis,decompensation events,liver transplantation(LT),and liver-related death were *** regression analysis was used to identify the risk factors associated with poor ***:A total of 183 patients were *** median age was 47 years,with 77.6%being *** a median follow-up of 4.8 years,88 patients developed compensated or decompensated cirrhosis,27 died,and 15 received *** Cox regression analysis showed that hepatocellular cholestasis(HR 2.953,95%CI:1.437–6.069),foam cells(HR 2.349,95%CI:1.092–5.053),and advanced fibrosis(HR 2.524,95%CI:1.313–4.851)were independent predictors of LT or liver-related deaths.A nomogram formulated with the above factors showed good consistency with a concordance index of 0.746(95%CI:0.706–0.785).Conclusions:Nearly half of VBDS patients studied progressed to end-stage liver disease and 23%of them had LT or liver-related death within two years of *** cholestasis,foam cells and advanced fibrosis rather than the degree of bile duct loss or underlying etiologies were independently associated with poor prognosis in VBDS patients.

关键词： Bile duct loss Prognosis Cholestasis Foam cells Advanced fibrosis

Overview of multiplex immunohistochemistry/immunofluorescence techniques in the era of cancer immunotherapy

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Cancer Communications 2020年第4期40卷 135-153页

作者： Wei Chang Colin Tan Sanjna Nilesh Nerurkar Hai Yun Cai Harry Ho Man Ng Duoduo Wu Yu Ting Felicia wee Jeffrey Chun Tatt Lim Joe Yeong Tony Kiat Hon Lim yong Loo Lin School of Medicine National University of SingaporeSingapore169856Singapore Department of Anatomical Pathology Singapore General HospitalSingapore169856Singapore Institute of Molecular Cell Biology(IMCB) Agency of ScienceTechnology and Research(A*STAR)Singapore169856Singapore Singapore Immunology Network Agency of Science(SIgN)Technology and Research(A*STAR)Singapore169856Singapore Duke-NUS Medical School Singapore169856Singapore

Conventional immunohistochemistry(IHC)is a widely used diagnostic technique in tissue ***,this technique is associated with a number of limitations,including high inter-observer variability and the capacity to label only one marker per tissue *** review details various highly multiplexed techniques that have emerged to circumvent these constraints,allowing simultaneous detection of multiple markers on a single tissue section and the comprehensive study of cell composition,cellular functional and cell-cell *** these techniques,multiplex Immunohistochemistry/Immunofluorescence(mIHC/IF)has emerged to be particularly ***/IF provides high-throughput multiplex staining and standardized quantitative analysis for highly reproducible,efficient and cost-effective tissue *** technique has immediate potential for translational research and clinical practice,particularly in the era of cancer immunotherapy.

关键词： immunofluorescence immunohistochemistry immunotherapy multiplex overview