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Natural and Anthropic Sources of Arsenic in the Groundwater and Soils of the Mekong Delta

Open Journal of Soil Science 2022年第11期12卷 541-570页

作者： Kenneth R. Olson Khoi Minh chau College of Agricultural Consumer and Environmental Sciences University of Illinois Urbana USA College of Agriculture Can Tho University Can Tho Vietnam

Human exposure to arsenic (As) is primarily through drinking water and food ingestion. Arsenic is naturally present in the environment and has been known as “the king of poisons” since the Middle Ages. It is mutagenic, teratogenic, and carcinogenic and approximately 70% comes from ingested food and 29% from water. Once ingested, arsenic can bio-accumulate in the human body or be excreted. Arsenic in groundwater is a main source of As in humans and the two arsenicals most abundant in water are arsenite (+3 oxidation state) and arsenate (+5 oxidation state). In order of toxicity from the most toxic to least toxic are arsines, arsenites, arsenoxides, arsenates, pentavalent arsenicals, Arsenic compounds, and metallic arsenic. Arsenic accumulates in the body when ingested in small doses. It often takes decades before physical symptoms of As poisoning show. While As is element normally found in the human body, it is highly toxic in excess amounts. The lethal dose for rates is 48 μg/L which translates to 125 mg for a middle-aged male. The maximum safe limit for As ingestion for an average Vietnamese middle-aged male is 220 μg per day. This lethal dosage puts As in a highly toxic category in food and toxicology. Most of the As in the Mekong Delta groundwater is from natural alluvial sediment sources. Other anthropic sources include the burial of millions of Vietnamese with elevated As levels since 1962, industrial sources, smelting by-products, water treatment plants, sewage and wastewater treatment discharges into waterways have added to the Mekong Delta As levels in the soil and groundwater. However, Agent Blue, the As-based herbicide, used during the Vietnam War, did contribute a significant amount (over 1,132,400 kg of manufactured (anthropic) As) to Southern Vietnam landscape. The As spikes and levels in the Mekong Delta soils and groundwater need restoration. The uptake of trace amounts of As in rice is indeed a critical food security and human health issue and requir

关键词： Arsenic Mekong Delta Anthropic Arsenic Agent Blue Khai Hoang Cacodylic Acid Water Treatment Plants

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MESANGIAL IgA GLOMERULONEPHRITIS IN HONG KONG A CLINICAL REVIEW

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中华医学杂志(英文版) 1986年第11期99卷 908-909页

作者： MK Chan S Kwan CK Yeunk PY chau University of Hong Kong Queen Mary HospitalHong Kong

Mesangial IgA glomerulonephritis accounts for 12% of all primary glomerulonephritis diagnosed from renal biopsies performed at Queen Mary Hospital. The clinical features of 106 patients with biopsy proven mesangial IgA glomerulonephritis seen at the renal clinic of the Department of Medicine, University of Hong Kong, were reviewed. There were 55 males and 51 females aged from 12 to 65 years with a mean of 28 years. Six groups of presenting features were recognized. Although the commonest was asymptomatic proteinuria and/or microscopic

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Upconversion luminescence of Gd2O3:Er3+and Gd2O3:Er3+/silica nanophosphors fabricated by EDTA combustion method

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Journal of Rare Earths 2019年第11期37卷 1126-1131页

作者： Le Quoc Minh Tran Kim Anh Nguyen Duy Hung Pham Thi Minh chau Nguyen Thi Quy Hai Ho Van Tuyen Vu Thi Thai Ha Vu Duc Tu Wieslaw Strek Institute of Theoretical and Applied Research Duy Tan UniversityDa Nang 55000Viet Nam Advanced Institute for Science and Technology Hanoi University of Science and Technology1 Dai Co VietHai Ba TrungHanoiViet Nam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadCau Giay DistrictHanoiViet Nam Institute of Low Temperature and Structure Research Polish Academy of Science 2 OkolnaWroclawPoland

Gd2O3:Er^3+nanophosphors were fabricated by the combustion method in presence of Na2 ethylene diamine tetra acetic acid(EDTA-Na2)as fuel at not high temperature(≤350℃)within a very short time of 5 *** added concentration of Er^3+ions in Gd2O3 matrix was changed from 0.5 mol%to 5.0 mol%.The X-ray diffraction pattern of samples indicates the monoclinic structure of Gd2O3:Er^3+.The morphology and chemical composition analysis of the Gd2O3:Er^3+samples are characterized by a field emission scanning electron microscope(FESEM)and a Fourier-transform infrared spectrometer(FTIR).The photoluminescence(PL),photo luminescence excitation(PLE)and upconversion(UC)at room temperature of the prepared materials with different concentrations of Er^3+were *** PL of Gd2O3:Er^3+nanomaterials are shown in visible at 545,594,623,648,688 nm under excitation at 275 *** emission bands from transitions of Er^3+from 2P3/2 to 4F9/2 are observed,UC luminescent spectra of the Gd2O3:Er^3+/silica nanocomposites under 976 nm excitation show the bands at 548 and 670 *** influence of excitation power at 980 nm for transitions were measured and *** results indicate that the upconversion process of Gd2O3:Er^3+/silica is two photons absorption *** low temperature dependence of UC luminescent intensities of the main bands of Gd2O3:Er^3+was investigated towards development of a nanotemperature sensor in the range of 10-300 K.

关键词： Upconversion luminescence Gd2O3:Er3+ Gd2O3:Er3+/silica Nanophosphors EDTA combustion Rare earths

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Psychological quality of life and employability skills among newly registered first-year students: Opportunities for further university development

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Health 2013年第3期5卷 617-626页

作者： Michèle Baumann Senad Karavdic Nearkasen chau INSERM U669 University of Paris-Sud and Paris Descartes University Paris France Research Unit INSIDE University of Luxembourg Walferdange Luxembourg

In accord with new European university reforms initiated by the Bologna Process, our objective was to evaluate influences on the relationship between psychological quality of life (QoL) and the acquisition of academic employability skills (AES) among first-year students at the University in Luxembourg. At the beginning (2 months in) and the end (9 months) of the academic year, 973 newly registered students participated in this study involving two cross-university surveys. Students who redoubled or who had studied at other universities were excluded. Data were collected with an online questionnaire comprising the psychological Whoqol-bref subscale, AES scale, and questions about other related factors. The AES score decreased from 74.2 to 65.6. At both time points, the psychological Whoqol-bref was positively correlated with environmental and social relations QoL and perceived general health. Multiple regression models including interaction terms showed that a higher psychological QoL was associated with better general health (difference satisfied-dissatisfied 9.44), AES (slope 0.099), social relationships QoL (0.321), and environmental QoL (0.298). No interaction with time effects was significant, which indicates that the effects remain stable with time. If the university could maintain the QoL indicators at appropriate levels or manage decreases as they occur, it would have implications for health promotion and the creation of new student support systems. The SQA- LES project provides valuable information for universities aiming to develop a European Higher Educational Area.

关键词： Psychological WHOQoL-Bref Newly-Registered Students Academic Employability Skills Quality of Life

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白藜芦醇对HCV增殖影响的研究

白藜芦醇对HCV增殖影响的研究

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作者： chau Pingsaymang Manpoong 吉林大学

学位级别：硕士

HCV感染是日益受到关注的全球公共卫生问题，是慢性肝脏疾病的主要病因之一。近1.3-1.7亿的人口是慢性HCV感染者，占世界人口的2-3%。慢性HCV感染者，20年后进展为肝硬化的概率为4-24%，30年后罹患原发性肝癌的概率为1–3%。HCV治疗随着... 详细信息

HCV感染是日益受到关注的全球公共卫生问题，是慢性肝脏疾病的主要病因之一。近1.3-1.7亿的人口是慢性HCV感染者，占世界人口的2-3%。慢性HCV感染者，20年后进展为肝硬化的概率为4-24%，30年后罹患原发性肝癌的概率为1–3%。HCV治疗随着对HCV基因组和分子病毒学领域的深入研究而取得了新的进展，HCV蛋白酶抑制剂（DAA）的出现更是将该领域的研究推向巅峰。自2011年9种DAA药物的上市，在HCV治疗上，获得高达≥90%持续的病毒学应答率（SVR）突破性的进展,且有较小的副作用;然而，高额的治疗费用仍是限制大多数新兴的DAA药物应用的重要因素，大部分急需治疗的患者不能及时用药导致病毒清除的失败。虽然在过去的10余年，HCV感染的治疗取得了很多突破性的进展，但目前仍未有获得审批的疫苗，同时DAA药物的高额费用限制了DAA药物的使用，这使新的治疗手段的开发尤为必要。白藜芦醇(RVT)是一种存在于多种植物及水果中的多酚类化合物。研究表明，这种酚类合成物是长寿基因（sirtuin）的强效激活剂，该基因与寿命的长短有关，同时被认为是饮用红酒时产生多酚类化合物中最为有益的成分，也被称为：法国悖论（法国人酷爱美食，平时饮食中摄取大量高卡路里和高胆固醇的食物，但得心血管疾病的几率却比英语国家的人要低得多）。多酚白藜芦醇分子中含有亚甲基桥隔开的两个苯环的分子，是第一个发现能够通过刺激的SIRT分泌发挥作用。Sirtuins1-7（SIRT1-7）属于第三类脱乙酰基酶，它依赖于NAD+的发挥活化作用。 SIRT可以参与基因抑制，代谢控制，细胞凋亡和细胞存活，DNA修复，神经保护和老龄化等调节作用。到目前为止研究最广泛的一直是SIRT1。 AMPK和SIRT1是构成RVT的两个关键指标。RVT可以抑制线粒体ATP生产，导致了更高的AMP/ATP比和AMPK的LKB1依赖性活化。然后，AMPK可以提高NAD+供应，该辅因子能够提高SIRT1的酶活性，从而改善速率限制。本研究的目的旨在探讨白藜芦醇对HCV繁殖周期的影响。据报道，白藜芦醇有抗肿瘤、抗炎症、抑制肥胖以及抗细菌的特性，同时又具有保护心血管系统的功能。白藜芦醇在非酒精性肝脏疾病中具有升高炎症因子的作用。此外，前期研究表明白藜芦醇可以抑制人类巨细胞病毒（HCMV）、单纯疱疹病毒(HSV-1)、水痘-带状疱疹病毒和甲型流感病毒的复制。在本研究中使用huh7.5.1细胞系来完成实验，首先对白藜芦醇的细胞毒性进行评价，在两个细胞培养基中分别加0ug/ml、1ug/ml、3ug/ml、5ug/ml、6ug/ml、7ug/ml、8ug/ml、10ug/ml、13ug/ml，其中一个培养基培养48h、另一个培养96h，之后用MTT试剂盒检测细胞活性，发现0-5ug/ml时,细胞大多数都有活性，然而6-13ug/ml时细胞死亡明显，因此白藜芦醇通过评价，最终选择出没有细胞毒性的剂量。本实验通过检测细胞培养衍生的HCV颗粒（HCVcc）中的JCR-2a进行研究，JCR-2a是一种新颖的单顺反子海肾荧光素酶受体病毒，这种病毒是通过HCV2a型转染质粒Jc1后得到。JCR-2a标记的HCV颗粒可以在体外存在，因此，是一种广泛使用丙型肝炎病毒完整的复制周期模型。首先，将JCR-2a转染细胞，4h后加不同浓度（0、1、3、5ug/ml）的白藜芦醇,继续培养72h,向细胞培养基中加底物（底物和单顺反子海肾荧光素酶结合后会发出荧光），检测荧光强度进行分析细胞内JCR-2a复制情况，实验发现四组中无明显差异。其次，提取上述实验过程中的上清液体(内含有白藜芦醇和JCR-2a)，并分别将上清液体感染新的Huh7.5.1细胞系，培养72h，加入底物检测荧光强度，发现四组有明显差异，白藜芦醇浓度越高，越容易影响病毒对细胞的感染能力。由于以上实验不能明确白藜芦醇对于细胞释放HCV的影响，设计了下一步实验，选择Jc1病毒转染Huh7.5.1细胞系，4h后加不同浓度的白藜芦醇（0ug/ml、1ug/ml、3ug/ml、5ug/ml），继续培养48h,用ELISA的方法检测细胞内和细胞外的丙肝病毒核心蛋白，发现四组中细胞内和细胞外没有明显影响。同时应用Western blot检测细胞内的丙肝病毒核心蛋白，实验数据表明四组无明显影响。再次，为了进一步证实白藜芦醇对病毒进入细胞的影响，第一部分：将不同浓度的白藜芦醇（0ug/ml、1ug/ml、3ug/ml、5ug/ml）加入培养Huh7.5.1细胞的培养基4h后，去除上清中白藜芦醇，向内加入JCR-2a，培养4h后去除上清，加入新的培养液继续培养48h,检测荧光强度无明显影响。第二部分：将不同浓度的白藜芦醇（0ug/ml、1ug/ml、3ug/ml、5ug/ml）和JCR-2

关键词：丙型肝炎病毒白藜芦醇抗病毒

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The Effect of Hydraulic Retention Times and Loading Rates on the Removal of Pollutants from Fish Processing Wastewater by Anaerobic Process

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Journal of Food Science and Engineering 2018年第6期8卷 237-240页

作者： Dao Khanh chau Tran Thanh Dai Faculty of Health and Applied Sciences Dong Nai Technology UniversityNguyen Khuyen StreetTrang Dai ward 810000Bien Hoa cityDong Nai provinceVietnam

Anaerobic treatment model treats fish processing wastewater to be necessary for a small and medium factory that is very popular in Vietnam and other *** techniques have been ***,they are quite expensive and hard to operate,especially in remote *** this study,the hydraulic retention times(HRT)including 3,5,and 7 hours with a various organic loading rate of 1.5 to 6.5 kg COD/m3/day were *** concentration as mix-liquor volatile suspended solid(MLVSS)in the model is at 6,000 to 9,000 mg/*** the basis of the result the optimal HRT with a 4.0 kg COD/m3/day organic loading rate was 8 hours which BOD5,COD removal efficiency were 92.18,87.36 percent *** the end of the optimal hydraulic retention times,the total methane gas volume as a by-product was collected with 2.6 liters.

关键词： Wastewater treatment anaerobic process hydraulic retention time organic loading rate

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The reaction of 2'2'3'3'-tetrafluoropropyl-5-iodo-3-oxaoctafluoropentane sulfonate with dimethylsulfoxide and determination of the crystal structure of one of the products

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Chinese Journal of Chemistry 1984年第1期2卷 13-17页

作者： LI Zong-Zhen NI chau-Zhou MA Yi-Lin Shanghai Institute of Organic Chemistry Academia Sinica,Shanghai Shanghai Institute of Organic Chemistry Academia Sinica Shanghai

The title reaction gave three known compounds（2,3 and 4）and two new compounds,CH3SCH2（CF2）2H（5）and I（C2）2O（CF2）2SO3-S+（CH3）3（6）.The structure of 6 was confirmed by X-raydiffraction *** crystals of 6 belong to monoclinic space group P21/C with a=9.399,b=15.651,c=10.934A,β=94.80°and z=*** structure was solved by heavy-atom method andrefined by block-diagonal matrix least-squares procedure to a final R of 0.054 for 1999 independentobserved *** S-C bonds around the sulphur atom in trimethylsulphonium are pyramidal with the bondlengths of 1.814A,1.800 A and 1.818 A and the bond angles C-S-C of 101.06°,101.52°and 102.53°.The distances of the sulphur atom in trimethylsulphonium to three oxygen atoms in the sulphonateradical are 3.79 A,*** 3.34 A *** distances are out of the range of the normalS-O bond *** structure consists of trimethylsulphonium cations and 5-iodo-3-oxaoctafluoro-pentane-sulphonate anions.

关键词： The reaction of 2’2’3’3 tetrafluoropropyl-5-iodo-3-oxaoctafluoropentane sulfonate with dimethylsulfoxide and determination of the crystal structure of one of the products

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Comparison of murine cirrhosis models induced by hepatotoxin administration and common bile duct ligation

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World Journal of Gastroenterology 2005年第27期11卷 4167-4172页

作者： Ming-Ling Chang chau-Ting Yeh Pei-Yeh Chang Jeng-Chang Chen Liver Research Unit Department of Hepatogastroenterology Chang Gung Memorial HospitalTaoyuan Taiwan China Department of Surgery Chang Gung Children's Hospital Taoyuan Taiwan China

AIM： To build up the research models of hepatic fibrosis in ***： Inbred wild-type FVB/N mice were either treated with alpha-naphthyl-isothiocyanate （ANIT）, allyl alcohol （AA）,carbon tetrachloride （CCl4）, 3,5-diethoxycarbonyl-l,4-dihydrocollidine （DDC）, and silica, or subjected to common bile duct ligation （CBDL） to induce hepatic injury. Liver biopsies were performed every 4 wk to evaluate hepatic fibrosis over a period of 6 mo. Cumulative cirrhosis and survival curves were constructed by life table method and compared with Wilcoxon ***： Under the dosages used, there was neither mortality nor cirrhosis in AA and silica-treated groups. DDC and ANIT caused cirrhosis within 4-12 and 12-24 wk, *** showed significantly faster cirrhosis induction at high dosages without significant alteration of survival. The duration for cirrhosis induction by CCl4 ranged from 4 to 20 wk, mainly dependent upon the dosage. However, the increase in CCl4 dosage significantly worsened survival. Intraperitoneal CCl4 administration resulted in better survival in comparison with garage administration at high dosage, but not at medium and low dosages. After CBDL, all the mice developed liver cirrhosis within 4-8 wk and then died by the end of 26 ***： CBDL and administrations of ANIT, CCl4, and DDC ensured liver cirrhosis. CBDL required the least amount of time in cirrhosis induction, but caused shortened lives of mice. It was followed by DDC and ANIT administration with favorable survival. As for CCl4, the speed of cirrhosis induction and the mouse survival depended upon the dosages and the administration route.

关键词： Common bile duct ligation Fibrosis Hepatotoxin Liver Mice

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Design and Analysis of Double-Stator Permanent Magnet Brushless Motor for Hybrid Electric Vehicles

Design and Analysis of Double-Stator Permanent Magnet Brushl...

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11th International Conference on Electrical Machines and Systems

作者： K.T.chau School of Electrical Engineering Southeast University Department of Electrical and Electronic Engineering the University of Hong Kong

＜正＞This paper presents the design and analysis of a new double-stator permanent brushless（DSPMBL） *** corresponding output power equation is analytically *** initial calculation of motor dimensions and parameters,including, the core diameter,stack length,permanent magnet size,and winding turns,are also discussed.A DSPMBL motor is designed. By using finite element analysis,the field distributions of the DSPMBL motor at different loads and rotor positions are *** static characteristics of the proposed motor are also *** on these characteristics,the system mathematics model can be ***,the evaluation of system performance is conducted by computer simulation.

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Advances in endovascular aneurysm management: flow modulation techniques with braided mesh devices

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Stroke & Vascular Neurology 2020年第1期5卷 1-13页

作者： Jessica K Campos Barry Cheaney II Brian V Lien David A Zarrin chau D Vo Geoffrey P Colby Li-Mei Lin Alexander L Coon Department of Neurosurgery University of California Irvine School of MedicineOrangeCaliforniaUSA Oregon Health and Science University School of Medicine PortlandOregonUSA Neurosurgery Johns Hopkins UniversityBaltimoreMarylandUSA Johns Hopkins University School of Medicine BaltimoreMarylandUSA UCLA Neurosurgery Ronald Reagan UCLA Medical CenterLos AngelesCaliforniaUSA Carondelet Neurological Institute St.Joseph's HospitalCarondelet Health NetworkTucsonArizonaUnited States

Flow diverters and flow disruption technology,alongside nuanced endovascular techniques,have ushered in a new era of treating cerebral ***,we provide an overview of the latest flow modulation devices and highlight the... 详细信息

关键词： flow braided hered

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