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| 1 | 北京大气细粒子PM_(2.5)的化学组成显示文摘为了解北京大气细粒子(PM2.5)的污染水平和污染特征,在车公庄和清华园进行了连续1年、每周1次同步采样和全样品分析。2个采样点PM2.5的化学组成相似。含碳组分和水溶性离子是主要的组分,其质量浓度之和超过PM2.5的50%。有机碳、元素碳和细粒子PM2.5的季节变化一致,即冬季质量浓度最高,夏季最低。夏季NO-3的质量浓度最低且在采样过程中从特氟隆滤膜上有近50%的挥发。SO2-4不同于PM2.5的季节变化主要取决于SO2的转化率。地壳元素的质量浓度从冬季到春季大幅度上升,春季沙尘天气频是一个重要原因。 | 杨复沫 贺克斌 马永亮 张强 姚小红 Chak K. Chan Steven Cadle Tai Chan Patricia Mulawa | 2002 | 清华大学学报(自然科学版)2002，42，12： | 116 |
| 2 | Air pollution in mega cities in China显示文摘 | Chak K. Chan Xiaohong Yao | 2007 | Atmospheric Environment2007，，1： | 10 |
| 3 | Photochemical smog in China:scientific challenges and implications for air-quality policies显示文摘INTRODUCTION Severe air-pollution events in many parts of China pose a major threat to health and ecosystems[1].China’s air pollution is concentrated to economically developed areas,such as Beijing–Tianjin–Hebei(BTH)and Pearl–River–Delta(PRD)[2,3].The situation has received considerable attention in | Mattias Hallquist John Munthe Min Hu Tao Wang Chak K Chan Jian Gao Johan Boman Song Guo Asa M Hallquist Johan Mellqvist Jana Moldanova Ravi K Pathak Jan BC Pettersson Hakan Pleijel David Simpson Marie Thynell | 2016 | National Science Review2016，3，4： | 8 |
| 4 | Small bowel capsule endoscopy in patients with cardiac pacemakers and implantable cardioverter defibrillators:Outcome analysis using telemetry review显示文摘AIM:To determine if there were any interactions between cardiac devices and small bowel capsules secondary to electromagnetic interference (EMI) in patients who have undergone small bowel capsule endoscopy (SBCE).METHODS:Authors conducted a chart review of 20 patients with a cardiac pacemaker (CP) or implantable cardioverter defibrillator (ICD) who underwent continuous electrocardiographic monitoring during their SBCE from 2003-2008.authors searched for unexplained electrocardiogram (ECG) findings,changes in CP andICD set parameters,any abnormality in transmitted capsule data,and adverse clinical events.RESULTS:There were no adverse events or hemodynamically significant arrhythmias reported.CP and ICD set parameters were preserved.The majority of ECG abnormalities were also found in pre-or post-SBCE ECG tracings and the CP behavior during arrhythmias appeared appropriate.Two patients seemed to have episodes of undersensing by the CP.However,similar findings were documented in ECGs taken outside the time frame of the SBCE.One patient was observed to have a low signal encountered from the capsule resulting in lack of localization,but no images were lost.CONCLUSION:Capsule-induced EMI remains a possibility but is unlikely to be clinically important.CPinduced interference of SBCE is also possible,but is infrequent and does not result in loss of images transmitted by the capsule. | Justin R Cuschieri Mohammed N Osman Richard CK Wong Amitabh Chak Gerard A Isenberg | 2012 | World Journal of Gastrointestinal Endoscopy2012，4，3： | 6 |
| 5 | A GLP-1 analog lowers ER stress and enhances protein folding to ameliorate homocysteine-induced endothelial dysfunction显示文摘Hyperhomocysteinemia(HHcy)is an independent risk factor for cardiovascular diseases and increases mortality in type 2 diabetic patients.HHcy induces endoplasmic reticulum(ER)stress and oxidative stress to impair endothelial function.The glucagon-like peptide 1(GLP-1)analog exendin-4 attenuates endothelial ER stress,but the detailed vasoprotective mechanism remains elusive.The present study investigated the beneficial effects of exendin-4 against HHcy-induced endothelial dysfunction.Exendin-4 pretreatment reversed homocysteine-induced impairment of endothelium-dependent relaxations in C57BL/6 mouse aortae ex vivo.Four weeks subcutaneous injection of exendin-4 restored the impaired endothelial function in both aortae and mesenteric arteries isolated from mice with diet-induced HHcy.Exendin-4 treatment lowered superoxide anion accumulation in the mouse aortae both ex vivo and in vivo.Exendin-4 decreased the expression of ER stress markers(e.g.,ATF4,spliced XBP1,and phosphorylated eIF2α)in human umbilical vein endothelial cells(HUVECs),and this change was reversed by cotreatment with compound C(CC)(AMPK inhibitor).Exendin-4 induced phosphorylation of AMPK and endothelial nitric oxide synthase in HUVECs and arteries.Exendin-4 increased the expression of endoplasmic reticulum oxidoreductase(ERO1α),an important ER chaperone in endothelial cells,and this effect was mediated by AMPK activation.Experiments using siRNA-mediated knockdown or adenoviral overexpression revealed that ERO1αmediated the inhibitory effects of exendin-4 on ER stress and superoxide anion production,thus ameliorating HHcy-induced endothelial dysfunction.The present results demonstrate that exendin-4 reduces HHcy-induced ER stress and improves endothelial function through AMPK-dependent ERO1αupregulation in endothelial cells and arteries.AMPK activation promotes the protein folding machinery in endothelial cells to suppress ER stress. | Chak Kwong Cheng Jiang-Yun Luo Chi Wai Lau William Chi-shing Cho Chi Fai Ng Ronald Ching Wan Ma Xiao Yu Tian Yu Huang | 2021 | Acta Pharmacologica Sinica2021，42，10： | 6 |
| 6 | Hydrothermal fabrication and visible-light-driven photocatalytic properties of bismuth vanadate with multiple morphologies and/or porous structures for Methyl Orange degradation显示文摘Monoclinic BiVO4 with multiple morphologies and/or porous structures were fabricated using the hydrothermal strategy. The materials were characterized by means of the XRD, Raman, TGA/DSC, SEM, XPS, and UV-Vis techniques. The photocatalytic activities of the BiVO4 materials were evaluated for the degradation of Methyl Orange under visible-light irradiation. It is observed that pH value and surfactant exerted a great effect on the morphology and pore structure of the BiVO4 product. Spherical BiVO4 with porous structures, flower-cluster-like BiVO4, and flower-bundle-like BiVO4 were generated hydrothermally at 100°C with poly(vinyl pyrrolidone) (PVP) and urea (pH = 2) and at 160°C with NaHCO3 (pH = 7 and 8), respectively. The PVP-derived BiVO4 showed much higher surface areas (5.0-8.4 m2/g) and narrower bandgap energies (2.45-2.49 eV). The best photocatalytic performance of the spherical BiVO4 material with a surface area of 8.4 m2/g was associated with its higher surface area, narrower bandgap energy, higher surface oxygen vacancy density, and unique porous architecture. | Haiyan Jiang Hongxing Dai Xue Meng Lei Zhang Jiguang Deng Yuxi Liu Chak Tong Au | 2012 | Journal of Environmental Sciences2012，24，3： | 5 |
| 7 | Quality indicators for colonoscopy显示文摘 | Douglas K. Rex John L. Petrini Todd H. Baron Amitabh Chak Jonathan Cohen Stephen E. Deal Brenda Hoffman Brian C. Jacobson Klaus Mergener Bret T. Petersen Michael A. Safdi Douglas O. Faigel Irving M. Pike | 2006 | Gastrointestinal Endoscopy2006，，4： | 4 |
| 8 | Porous FeO_x/BiVO_(4-δ)S_(0.08): Highly efcient photocatalysts for the degradation of Methylene Blue under visible-light illumination显示文摘Porous S-doped bismuth vanadate with an olive-like morphology and its supported iron oxide(y wt.% FeOx/BiVO4 δS0.08, y =0.06, 0.76, and 1.40) photocatalysts were fabricated using the dodecylamine-assisted alcohol-hydrothermal and incipient wetness impregnation methods, respectively. It is shown that the y wt.% FeOx/BiVO4 δS0.08photocatalysts contained a monoclinic scheetlite BiVO4 phase with a porous olive-like morphology, a surface area of 8.8–9.2 m2/g, and a bandgap energy of 2.38–2.42 eV. There was co-presence of surface Bi5+, Bi3+, V5+, V3+, Fe3+, and Fe2+species in y wt.% FeOx/BiVO4 δS0.08. The 1.40 wt.% FeOx/BiVO4 δS0.08sample performed the best for Methylene Blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and FeOx co-doping, higher oxygen adspecies concentration, and lower bandgap energy were responsible for the excellent visible-light-driven catalytic activity of 1.40 wt.% FeOx/BiVO4 δS0.08. | Zhenxuan Zhao Hongxing Dai Jiguang Deng Yuxi Liu Yuan Wang Xinwei Li Guangmei Bai Baozu Gao Chak Tong Au | 2013 | Journal of Environmental Sciences2013，25，10： | 4 |
| 9 | Using Imbalanced Triangle Synthetic Data for Machine Learning Anomaly Detection显示文摘The extreme imbalanced data problem is the core issue in anomaly detection.The amount of abnormal data is so small that we cannot get adequate information to analyze it.The mainstream methods focus on taking fully advantages of the normal data,of which the discrimination method is that the data not belonging to normal data distribution is the anomaly.From the view of data science,we concentrate on the abnormal data and generate artificial abnormal samples by machine learning method.In this kind of technologies,Synthetic Minority Over-sampling Technique and its improved algorithms are representative milestones,which generate synthetic examples randomly in selected line segments.In our work,we break the limitation of line segment and propose an Imbalanced Triangle Synthetic Data method.In theory,our method covers a wider range.In experiment with real world data,our method performs better than the SMOTE and its meliorations. | Menghua Luo Ke Wang Zhiping Cai Anfeng Liu Yangyang Li Chak Fong Cheang | 2019 | Computers, Materials & Continua2019，，1： | 4 |
| 10 | Spectral Analysis for HSS Preconditioners显示文摘In this paper,we are interested in HSS preconditioners for saddle point lin- ear systems with a nonzero(2,2)-th block.We study an approximation of the spectra of HSS preconditioned matrices and use these results to illustrate and explain the spectra obtained from numerical examples,where the previous spectral analysis of HSS precon- ditioned matrices does not cover. | Lung Chak Chan Michael K. Ng Nam Kiu Tsing | 2008 | Numerical Mathematics(Theory,Methods and Applications)2008，1，1： | 3 |
| 11 | Air pollution in mega cities in China显示文摘 | Chak K. Chan Xiaohong Yao | 2007 | Atmospheric Environment2007，，1： | 3 |
| 12 | Intravenous fluid selection rationales in acute clinical management显示文摘BACKGROUND: Intravenous fluid(IVF) is commonly used in acute clinical management. This study aimed to review the choice and primary considerations in IVF prescriptions and to evaluate the adequacy of guidelines and trainings on it in the New Territories West Cluster(NTWC) of Hong Kong.METHODS: This is a descriptive study based on data collected from an online survey. Data were processed by SPSS for statistical analysis. This study focused on a general description and doctor-nurse between group comparison. Participants were asked the choice of IVF for nine acute clinical scenarios and provide reason. A 1–10 scale was used to assess the sufficiency of guideline, training and information, and time for revision on IVF prescription.RESULTS: 0.9% sodium chloride was the most familiar IVF(36%), followed by 5% Dextrose solution(26%). In the nine scenarios, the most chosen IVF was 0.9% sodium chloride(37%–61%). There was significant difference in the choice of IVF between doctors and nurses in 7 cases. The second most chosen IVF for doctors was Plasma-Lyte A while that for nurses was Gelofusine. Departmental practice was the most chosen reason to account for the prescription. The adequacy of guideline, information and training, and time for revision was rated 5. Doctors had significantly more time at work than nurses to update knowledge in IVF prescription(5.41 versus 4.57).CONCLUSION: 0.9% sodium chloride was mostly chosen. The choice of IVF was mainly based on departmental practice. Adequacy of guideline, information and training, and time for revision on IVF prescription were average, indicating significant training deficit. | Wing Yan Shirley Cheung Wai Kwan Cheung Chun Ho Lam Yeuk Wai Chan Hau Ching Chow Ka Lok Cheng Yau Hang Wong Chak Wah Kam | 2018 | World Journal of Emergency Medicine2018，9，1： | 3 |
| 13 | Feasibility, safety, acceptability, and yield of office-based, screening transnasal esophagoscopy (with video)显示文摘 | Anne F. Peery Toshitaka Hoppo Katherine S. Garman Evan S. Dellon Norma Daugherty Susan Bream Alejandro F. Sanz Jon Davison Melissa Spacek Diane Connors Ashley L. Faulx Amitabh Chak James D. Luketich Nicholas J. Shaheen Blair A. Jobe | 2012 | Gastrointestinal Endoscopy2012，，5： | 2 |
| 14 | Lack of evidence of active lytic replication of Epstein-Barr and cytomegaloviruses in patients with systemic lupus erythematosus显示文摘LackofevidenceofactivelyticreplicationofEpsteinBarrandcytomegalovirusesinpatientswithsystemiclupuserythematosusLauChakSing,... | Lau Chak Sing, Yuen Yung, Chan Hung and Wong Raymond Woon Sing | 1998 | Chinese Medical Journal1998，，7： | 2 |
| 15 | Size-resolved effective density of submicron particles during summertime in the rural atmosphere of Beijing, China显示文摘Particle density is an important physical property of atmospheric particles.The information on high time-resolution size-resolved particle density is essential for understanding the atmospheric physical and chemical aging processes of aerosols particles.In the present study,a centrifugal particle mass analyzer(CPMA) combined with a differential mobility analyzer(DMA) was deployed to determine the size-resolved effective density of 50 to 350 nm particles at a rural site of Beijing during summer 2016.The measured particle effective densities decreased with increasing particle sizes and ranged from 1.43 to 1.55 g/cm^3,on average.The effective particle density distributions were dominated by a mode peaked at around 1.5 g/cm^3 for 50 to350 nm particles.Extra modes with peaks at 1.0,0.8,and 0.6 g/cm3 for 150,240,and 350 nm particles,which might be freshly emitted soot particles,were observed during intensive primary emissions episodes.The particle effective densities showed a diurnal variation pattern,with higher values during daytime.A case study showed that the effective density of Aitken mode particles during the new particle formation(NPF) event decreased considerably,indicating the significant contribution of organics to new particle growth. | Kai Qiao Zhijun Wu Xiangyu Pei Qianyun Liu Dongjie Shang Jing Zheng Zhuofei Du Wenfei Zhu Yusheng Wu Shengrong Lou Song Guo Chak K.Chan Ravi Kant Pathak Mattias Hallquist Min Hu | 2018 | Journal of Environmental Sciences2018，30，11： | 2 |
| 16 | Quality indicators for colonoscopy显示文摘 | Douglas K. Rex John L. Petrini Todd H. Baron Amitabh Chak Jonathan Cohen Stephen E. Deal Brenda Hoffman Brian C. Jacobson Klaus Mergener Bret T. Petersen Michael A. Safdi Douglas O. Faigel Irving M. Pike | 2006 | Gastrointestinal Endoscopy2006，，4： | 2 |
| 17 | Low-efficiency-droop InGaN quantum dot light-emitting diodes operating in the “green gap”显示文摘Gallium nitride(Ga N)-based light-emitting diodes(LEDs)are important for lighting and display applications.In this paper,we demonstrate green-emission(512 nm)In Ga N quantum dot(QD)LEDs grown on a c-plane sapphire substrate by metal-organic chemical vapor deposition.A radiative lifetime of 707 ps for the uniform In Ga N self-assembled QDs is obtained by time-resolved photoluminescence measurement at 18 K.The screening of the built-in fields in the QDs effectively improves the performance of QD LEDs.These high quantum efficiency and high temperature stability green QD LEDs are able to operate with negligible efficiency droop and with current density up to 106 A∕cm^2.Our results show that In Ga N QDs may be a viable option as the active medium for stable LEDs. | CHUNYU ZHAO CHAK WAH TANG BILLY LAI GUANGHUI CHENG JIANNONG WANG KEI MAY LAU | 2020 | Photonics Research2020，8，5： | 2 |
| 18 | Development of Subsquamous High-Grade Dysplasia and Adenocarcinoma After Successful Radiofrequency Ablation of Barrett’s Esophagus显示文摘 | Mohammad Titi Andrew Overhiser Ozlem Ulusarac Gary W. Falk Amitabh Chak Kenneth Wang Prateek Sharma | 2012 | Gastroenterology2012，，3： | 2 |
| 19 | Preliminary results of antiscarring therapy in the prevention of postendoscopic esophageal mucosectomy strictures显示文摘 | Yuhsin Wu Steve J. Schomisch Cassandra Cipriano Amitabh Chak Richard H. Lash Jeffrey L. Ponsky Jeffrey M. Marks | 2014 | Surgical Endoscopy2014，，2： | 2 |
| 20 | Concentration and chemical composition of PM 2.5 in Shanghai for a 1-year period显示文摘 | Boming Ye Xueli Ji Haizhen Yang Xiaohong Yao Chak K Chan Steven H Cadle Tai Chan Patricia A Mulawa | 2002 | Atmospheric Environment2002，，4： | 2 |
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