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Laboratory Experiments for Arsenic and Ammonium Removal The Combination of Breakpoint Chlorination and Iron（Ⅲ）-Coagulation

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Journal of Environmental Science and Engineering(A) 2012年第10期1卷 1165-1172页

作者： Szabolcs takó Dóra Laky Department of Sanitary and Environmental Engineering Budapest University of Technology and Economics Muegyetem rkp. 31111Budapest Hungary

Currently, 15% of the total Hungarian population is affected by either the elevated arsenic or ammonium concentration of drinking water, and 8% is affected by both compounds. The break-point chlorination is a well-known method for ammonium removal, however, during the ammonium-removal process carcinogenic and mutagenic by-products （e.g., THM （trihalogenmethane） and AOX （absorbable organically bound halogens）） may be formed. In order to remove these harmful organic by-products, activated carbon adsorption has to be applied in the technology. The break-point chlorine dose is capable of oxidizing the As3＋ to As5＋. The oxidized form of arsenic can be easily converted to solid phase by adding coagulant （Fe（Ⅲ） or AI（Ⅲ） salt） to the water, and the formed iron/aluminium flocs can be removed by simple rapid sand filtration. Laboratory experiments were performed with raw water from two Hungarian settlements, where the water originated from a deep confined aquifer. In the studied settlements, six wells were in operation, and the supplied drinking water contained ammonium above the maximum allowable concentration, and the arsenic content was around the 10 μg/L standard value. It was found that higher chlorine dose （- 10 Cl2：NH4-N） was needed to achieve the breakpoint than the theoretical value （7.6）. The amount of by-products was also measured during the experiments. The AOX concentrations were significantly higher （21.6 μg/L to 143μg/L） in all cases than the THM concentrations （9-18 μg/L）. The needed coagulant doses were also studied in order to achieve the required arsenic concentrations. Fe（Ⅲ） coagulant was applied in all cases, and it was found that 1-1.5 mg/L Fe（Ⅲ） dose was sufficient to achieve 2-5 μg/L arsenic concentration in the treated water. Based on the results, it can be stated that the breakpoint chlorination combined with Fe（Ⅲ） coagulation is a potential technology to achieve the required ammonium and arsenic concentration at the studied settlements. However, act

关键词： Drinking water breakpoint chlorination ammonium arsenic coagulation.

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Convective Heat Transfer in Bulk- and Boundary-Dominated Regimes in Turbulent Thermal Convection

Convective Heat Transfer in Bulk- and Boundary-Dominated Reg...

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第八届全国实验流体力学学术会议

作者：韦萍 Chan tak-Shing Department of Physics The ChineseUniversity of Hong Kong

We report Nusselt number measurements in rayleigh-Benard convection systems with modified boundary conditions and over the range of the rayleigh number(ra) spanning from 3×10 to 8×10 and with the Prandtl number Pr～*** measurements were made in three convection cells:(1) both the top and bottom plates of the cell have plat smooth surface;(2) the top plate has a flat smooth surface while the bottom plate has a rough surface in the form of regularly-arrayed pyramids;and(3) the top plate is rough as in(2) but the bottom plate is *** these cells have cylindrical shape with aspect ratio *** experimental results suggest that the Nu～ra relationship can be represented by the combination of two power laws,corresponding to the bulk-dominant regime(exponent = 1/2) and boundary layer dominant one(exponent =1/4) of the Grossmann-Lohse *** behaviors of the coefficients of the two power laws suggest that the roughness of the plate can enhance the contribution of bulk and push the system to change from the boundary dominant state to bulk dominant state.

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CYP24A1 inhibition facilitates the anti-tumor effect of vitamin D3 on colorectal cancer cells

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World Journal of Gastroenterology 2013年第17期19卷 2621-2628页

作者： János P Kósa Péter Horváth János Wlfling Dóra Kovács Bernadett Balla Péter Mátyus Evelin Horváth Gábor Speer István takács Zsolt Nagy Henrik Horváth Péter Lakatos 1 st Department of Internal Medicine Semmelweis University Department of Organic Chemistry University of Szeged Department of Organic Chemistry Semmelweis University

AIM:The effects of vitamin D3 have been investigated on various tumors, including colorectal cancer (CRC). 25-hydroxyvitamin-D3-24-hydroxylase (CYP24A1), the enzyme that inactivates the active vitamin D3 metabolite 1,25-dihydroxyvitamin D3 (1,25-D3), is considered to be the main enzyme determining the biological halflife of 1,25-D3. During colorectal carcinogenesis, the expression and concentration of CYP24A1 increases significantly, suggesting that this phenomenon could be responsible for the proposed efficacy of 1,25-D3 in the treatment of CRC. The aim of this study was to investigate the anti-tumor effects of vitamin D3 on the human CRC cell line Caco-2 after inhibition of the cytochrome P450 component of CYP24A1 activity. METHODS:We examined the expression of CYP24A1 mRNA and the effects of 1,25-D3 on the cell line Caco-2 after inhibition of CYP24A1. Cell viability and proliferation were determined by means of sulforhodamine-B staining and bromodeoxyuridine incorporation, respectively, while cytotoxicity was estimated via the lactate dehydrogenase content of the cell culture supernatant. CYP24A1 expression was measured by realtime reverse transcription polymerase chain reaction. A number of tetralone compounds were synthesized to investigate their CP24A1 inhibitory activity. RESULTS:In response to 1,25-D3, CYP24A1 mRNA expression was enhanced significantly, in a time- and dose-dependent manner. Caco-2 cell viability and proliferation were not influenced by the administration of 1,25-D3 alone, but were markedly reduced by coadministration of 1,25-D3 and KD-35, a CYP24A1-inhibiting tetralone. Our data suggest that the mechanism of action of co-administered KD-35 and 1,25-D3 does not involve a direct cytotoxic effect, but rather the inhibition of cell proliferation. CONCLUSION:These findings demonstrate that the selective inhibition of CYP24A1 by compounds such as KD-35 may be a new approach for enhancement of the anti-tumor effect of 1,25-D3 on CRC.

关键词： Colorectal cancer CYP24A1 inhibition Vitamin D3 Tetralone derivatives Caco-2 cell culture

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类风湿性滑膜炎:逐个像素的动态对比增强MRI时间信号强度曲线形态分析的可行性研究

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国际医学放射学杂志 2009年第6期 589-589页

作者： C.van der Leij M.G.H.van de Sande C.Lavini P.P.tak M.Maas 范文哲 Department of radiology Academic Medical CenterUniversity of AmsterdamMeibergdreef 9NL-1105 AZ Amsterdamthe Netherlands

目的分析不同形态的时间-信号强度曲线(shapesof timeintensity curves,TICs)在类风湿性关节炎(rheumatoidarthritis,ra)滑膜组织的分布,比较ra组与健康对照组TICs的相对数。材料与方法本前瞻性研究通过伦理委员会批准,ra病人及健康志... 详细信息

目的分析不同形态的时间-信号强度曲线(shapesof timeintensity curves,TICs)在类风湿性关节炎(rheumatoidarthritis,ra)滑膜组织的分布,比较ra组与健康对照组TICs的相对数。材料与方法本前瞻性研究通过伦理委员会批准,ra病人及健康志愿者均签署知

关键词：动态对比增强滑膜相对数对照组 ra 病人相对指标 MRI

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2010年类风湿关节炎分类标准——美国风湿病学会和欧洲抗风湿病联盟的联合倡议

2010年类风湿关节炎分类标准——美国风湿病学会和欧洲抗风湿病联...

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贵州省医学会风湿病学分会第四届学术年会

作者： Daniel Aletaha Tuhina Neogi Alan J Silman Julia Funovits David T Felson Clifton O Bingham Ⅲ Neal S Birnbaum Gerd R Burmester Vivian P Bykerk Marc D Cohen Bernard Combe Karen H Costenbader Maxime Dougados Paul Emery Gianfranco Ferraccioli Johanna MW Hazes Kathryn Hobbs Tom WJ Huizinga Arthur Kavanaugh Jonathan Kay Tore K Kvien Timothy Laing Philip Mease Henri A Menard Larry W Moreland raymond L Naden Theodore Pincus Josef S Smolen Ewa Stanislawska-Biernat Deborah Symmons Paul P tak Katherine S Upchurch Jiri Vencovsky Frederick Wolfe Gillian Hawker 季兰岚邓雪蓉赵明田真张卓莉 Medical University of Vienna ViennaAustria Boston University School of Medicine BostonMassachusettsUSA

目的 :在早期类风湿关节炎(rheumatoid arthritis,ra)的诊断中,1987年美国风湿病学会(AmericanCollege of Rheumatology,ACR;旧称AmericanRheumatism Association,Ara)的诊断标准因为缺乏敏感度而受到质疑。本研究的目的是建立新的ra分类标准。方法 :由ACR和欧洲抗风湿病联盟(EuropeanLeague Against Rheumatism,EULAR)共同组成的工作小组,分三个阶段建立ra新的分类标准。研究的目标人群是初发的未分化关节炎患者,主要研究目的是寻找能够预测这些病人发展为ra的危险因素,并将ra疾病特点定义为持续性和/或侵蚀性关节炎。结果 :在新的分类标准中,确诊ra至少需要一个关节有明确的滑膜炎表现,除外其他可能导致滑膜炎症的疾病,同时以下四项评分的总分≥6分(最高10分):受累关节的数量和部位(0-5分)、血清学自身抗体异常(0-3分)、急性期反应物升高(0-1分)和症状持续时间(共分两级;0-1分)。结论 :既往诊断ra比较依赖骨破坏这一ra晚期表现,而新的分类标准着重于疾病早期表现而不是晚期特点,将疾病特点重新定义为持续性和/或侵蚀性滑膜炎。这一新标准的推出将再次强调了ra早期诊断的必要性以及早期有效治疗对于预防或减少不良后遗症的发生具有重要意义。

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