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Method to assess component contribution to toxicity of complex mixtures： Assessment of puberty acquisition in rats exposed to disinfection byproducts

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Journal of Environmental Sciences 2017年第8期29卷 311-321页

作者： Shahid Parvez Glenn E.Rice Linda K.Teuschler Jane Ellen Simmons thomas f.Speth Susan D.Richardson Richard J.Miltner E.Sidney Hunter Ⅲ Jonathan G.Pressman Lillian f.Strader Gary R.Klinefelter Jerome M.Goldman Michael G.Narotsky Indiana University Richard M. fairbanks School of Public Health Department of Environmental Health Sciences IUPUI Campus Indianapolis IN 46202 USA National Center for Environmental Assessment Office of Research and Development U.S. Environmental Protection Agency Cincinnati OH 45268 USA Lincla Teuschler and Associates St. Petersburg FL 33707 USA National Health and Environmental Effects Research Laboratory Office of Research and Development U.S. Environmental Protection Agency Research Triangle Park NC 27711 USA National Risk Management Research Laboratory Office of Research and Development U.S. Environmental Protection Agency Cincinnati OH 45268 USA Department of Chemistry and Biochemistry University of South Carolina Columbia SC 29208 USA

A method based on regression modeling was developed to discern the contribution of component chemicals to the toxicity of highly complex, environmentally realistic mixtures of disinfection byproducts（DBPs）. Chemical disinfection of drinking water forms DBP *** of concerns about possible reproductive and developmental toxicity, a whole mixture（WM） of DBPs produced by chlorination of a water concentrate was administered as drinking water to Sprague–Dawley（S–D） rats in a multigenerational study. Age of puberty acquisition,i.e., preputial separation（PPS） and vaginal opening（VO）, was examined in male and female offspring, respectively. When compared to controls, a slight, but statistically significant delay in puberty acquisition was observed in females but not in males. WM-induced differences in the age at puberty acquisition were compared to those reported in S–D rats administered either a defined mixture（DM） of nine regulated DBPs or individual DBPs. Regression models were developed using individual animal data on age at PPS or VO from the DM study. Puberty acquisition data reported in the WM and individual DBP studies were then compared with the DM models. The delay in puberty acquisition observed in the WM-treated female rats could not be distinguished from delays predicted by the DM regression model, suggesting that the nine regulated DBPs in the DM might account for much of the delay observed in the WM. This method is applicable to mixtures of other types of chemicals and other endpoints.

关键词： Drinking water disinfection byproducts DBP Puberty delay four Lab Study Mixtures risk assessment

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基于有机激光材料的分子开关效应

基于有机激光材料的分子开关效应

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全国第八届有机固体电子过程暨华人有机光电功能材料学术讨论会

作者：李盛孙鑫 thomas f.George 浙江师范大学物理系美国密苏里大学圣路易斯分校纳米研究中心复旦大学物理系

共轭高聚物的自陷效应的存在,是实现反常的负的电极化成为可能。但是,现实中,实现这个效应的条件是粒子数反转,但普通的光激发无法满足实现负的电极化的条件,并且有机共轭高聚物中载流子的低迁移率无法实现在共轭高聚物中实现粒子数反...

共轭高聚物的自陷效应的存在,是实现反常的负的电极化成为可能。但是,现实中,实现这个效应的条件是粒子数反转,但普通的光激发无法满足实现负的电极化的条件,并且有机共轭高聚物中载流子的低迁移率无法实现在共轭高聚物中实现粒子数反转。最近报道基于共轭高聚物的电泵浦激光的实现,使得实现

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High-performance oxygen reduction and evolution carbon catalysis： from mechanistic studies to device integration

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Nano Research 2017年第4期10卷 1163-1177页

作者： John W. f. To Jia Wei Desmond Ng Samira Siahrostami Ai Leen Koh Yangjin Lee Zhihua Chen Kara D. fong Shucheng Chen Jiajun He Won-Gyu Bae Jennifer Wilcox Hu Young Jeong Kwanpyo Kim felix Studt Jens K. Nфrskov thomas f. Jaramillo Zhenan Bao Department of Chemical Engineering Stan ford University Stanford CA 94305 USA Institute of Chemical and Engineering Sciences Agency for Science Technology and Research Jurong Island 627833 Singapore Stanford Nano Shared facilities Stanford University Stanford CA 94305 USA Department of Physics Ulsan National Institute of Science and Technology (UNIST) Ulsan 689-798 Republic of Korea Department of Chemical and Biological Engineering Colorado School of Mines Golden CO 80401 USA UNIST Central Research facilities (UCRf) Ulsan National Institute of Science and Technology (UNIST) Ulsan 689-798 Republic of Korea SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park CA 94025 USA Institute of Catalysis Research and Technology Karlsruhe Institute of Technology Hermann-von-Helmholtz Platz 1 76344 Eggenstein-Leopoldshafen Germany Institute for Chemical Technology and Polymer Chemistry Karlsruhe Institute of Technology Engesserstr. 18 76131 Karlsruhe Germany

The development of high-performance and low-cost oxygen reduction and evolution catalysts that can be easily integrated into existing devices is crucial for the wide deployment of energy storage systems that utilize O2-H2O chemistries, such as regenerative fuel cells and metal-air batteries. Herein, we report an NHB-activated N-doped hierarchical carbon （NHC） catalyst synthesized via a scalable route, and demonstrate its device integration. The NHC catalyst exhibited good performance for both the oxygen reduction reaction （ORR） and the oxygen evolution reaction （OER）, as demonstrated by means of electrochemical studies and evaluation when integrated into the oxygen electrode of a regenerative fuel cell. The activities observed for both the ORR and the OER were comparable to those achieved by state-of-the-art Pt and Ir catalysts in alkaline environments. We have further identified the critical role of carbon defects as active sites for electrochemical activity through density functional theory calculations and high-resolution TEM visualization. This work highlights the potential of NHC to replace commercial precious metals in regenerative fuel cells and possibly metal-air batteries for cost-effective storage of intermittent renewable energy.

关键词： electrocatalysis porous carbon density functional theory

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Application of solvent pH under pressurized conditions using accelerated solvent extraction and green solvents to extract phytonutrients from wild berries

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food Bioscience 2022年第3期47卷 463-473页

作者： Amanda Rajakaruna Charles f.Manful Ibrahim M.Abu-Reidah Amber L.Critch Natalia P.Vidal Thu H.Pham Mumtaz Cheema Raymond thomas School of Science and the Environment Grenfell CampusMemorial University of NewfoundlandCorner BrookA2H 5G4Canada The functional foods Sensory Laboratory Grenfell CampusMemorial University of NewfoundlandCorner BrookA2H 5G4Canada

Berry fruits are known as“superfoods”due to health benefits associated with the high content of bioactive compounds or *** extraction solvents are fundamentally volatile compounds acquired from non-renewable resources,i.e petroleum-based solvents are presumed to be harmful to both human health and the *** to the new emphasis on environmental and safety protections and the development of green chemistry,finding alternative solvents to replace the organic ones has recently become a major ***,there is a great interest in the scientific community to develop a suitable green approach to allow the extraction and recovery of the bioactive phytonutrients from berry sources for applications in improving human health and *** this study,the phytonutrient composition of three popular wild berries:blueberry(Vaccinium angustifolium),partridgeberry(Vaccinium vitis-idaea L.)and Rosehipberry(Rosa canina),were evaluated following extraction using biphasic green solvents at pH 2.5,7.0,and 11.5 under pressurized conditions using Accelerated Solvent Extraction(ASE)*** total phenolic content and composition,antioxidant activity,vitamin and mineral content of the berry extracts were evaluated using folin-Ciocalteu assay,ferric Reducing Antioxidant Power Assay(fRAP),Ultra-High-pressure Liquid Chromatography-Mass Spectrometry(UHPLC-MS)and inductively coupled plasma-mass spectrometry(ICP-MS),*** highest total antioxidant activity(p≤0.05)and phenolic content were observed in rosehip berry followed by blueberry and partridgeberry in the hydroethanolic extracts at pH ***,the highest extraction efficiency of total fat-soluble vitamins(fSV)and total B vitamins were also observed in the hydroethanolic extract at pH *** in rosehipberry and partridgeberry the highest vitamin C content was observed in hydroethanolic extract at pH 11.5,whereas in blueberry it was observed in the pH 2.5 hydroethanolic extract.I

关键词： Wild berries Accelerated solvent extraction(ASE) Hydroethanolic extracts Alkaline pH Phytonutrients

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Experimental investigation of the aerodynamics of a large industrial building with parapet

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Advances in Aerodynamics 2021年第1期3卷 455-476页

作者： Aly Mousaad Aly Matthew thomas Hamzeh Gol-Zaroudi Windstorm Impact Science and Engineering(WISE)LaboratoryDepartment of Civil and Environmental EngineeringCollege of EngineeringLouisiana State University3230H Patrick F.Taylor HallBaton RougeLA 70803USA

The aerodynamic performance of a roof depends significantly on its shape and size,among other *** instance,large roofs of industrial low-rise buildings may behave differently compared to those of residential *** main objective of this study is to experimentally investigate how perimeter solid parapets can alter the flow pattern around a low-rise building with a large aspect ratio of width/height of about 7.6,the case of industrial buildings/shopping *** parapets of varied sizes are added to the roof and tested in an open-jet simulator in a comparative study to understand their impact on roof pressure *** pressures were measured in the laboratory for cases with and without parapets under different wind direction angles(representative of straight-line winds under open terrain conditions).The results show that using a parapet can alter wind pressures on large *** can modify the flow pattern around buildings and change the mean and peak *** mean pressure pattern shows a reduction in the length of the separation bubble due to the *** parapet of 14%of the building’s roof height is the most efficient at reducing mean and peak pressures compared to other parapet heights.

关键词： Aerodynamics Open-jet testing Turbulence Pressure measurement Lowrise buildings Parapet

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Serum bile acid profiling reflects enterohepatic detoxification state and intestinal barrier function in inlammatory bowel disease

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World Journal of Gastroenterology 2009年第25期15卷 3134-3141页

作者： Carsten Gnewuch Gerhard Liebisch thomas Langmann Benjamin Dieplinger thomas Mueller Meinhard Haltmayer Hans Dieplinger Alexandra Zahn Wolfgang Stremmel Gerhard Rogler Gerd Schmitz Institute of Clinical Chemistry and Laboratory Medicine Regensburg University Medical Center Institute of Human Genetics University of Regensburg Department of Laboratory Medicine Konventhospital Barmherzige Brueder Linz Division of Genetic Epidemiology Department of Medical GeneticsClinical and Molecular PharmacologyInnsbruck Medical University Department of Gastro-enterology University Hospital Heidelberg Department of Internal Medicine I Regensburg University Medical Center

AIM:To determine free and conjugated serum bile acid (BA) levels in in? ammatory bowel disease (IBD) subgroups with defi ned clinical ***: Comprehensive serum BA profiling was performed in 358 IBD patients and 310 healthy controls by liquid chromatography coupled to electrospray ionization tandem mass ***: Serum levels of hyodeoxycholic acid, the CYP3A4-mediated detoxification product of the secondary BA lithocholic acid (LCA), was increased significantly in Crohn's disease (CD) and ulcerative colitis (UC), while most other serum BA species were decreased significantly. Total BA, total BA conjugate, and total BA glycoconjugate levels were decreased only in CD, whereas total unconjugated BA levels were decreased only in UC. In UC patients with hepatobiliary manifestations, the conjugated primary BAs glycocholic acid, taurocholic acid, and glycochenodeoxycholic acid were as significantly increased as the secondary BAs LCA, ursodeoxycholic acid, and tauroursodeoxycholic acid compared to UC patients without hepatobiliary manifestations. finally, we found that in ileocecal resected CD patients, the unconjugated primary BAs, cholic acid and chenode-oxycholic acid, were increased significantly compared to controls and patients without surgical ***: Serum BA profiling in IBD patients that indicates impaired intestinal barrier function and increased detoxification is suitable for advanced diagnostic characterization and differentiation of IBD subgroups with defined clinical manifestations.

关键词：屏障功能胆汁酸炎症解毒血清肠肝

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Radio observations of the first three-months of fermi AGN at 4.8 GHz

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Research in Astronomy and Astrophysics 2012年第2期12卷 147-157页

作者： Nicola Marchili thomas P.Krichbaum Lars fuhrmann Anton Zensus Max-Plank-Institut fr Radioastronomie

Using the Urumqi 25 m radio telescope, sources from the first three months of the fermi-large area telescope detected active galactic nuclei （AGN） catalog with a declination of 〉 0° were observed in 2009 at 4.8 GHz. The radio flux density ap- peared to correlate with the γ-ray intensity. Intra-day variability （IDV） observations were performed in March, April and May 2009 for 42 selected γ-ray bright blazars, and ~60% of them showed evidence of flux variability at 4.8 GHz during the IDV observations. The IDV detection rate was higher than that in previous flat-spectrum AGN samples. IDV appeared more often in the very long baseline interferometry-core dominant blazars, and the non-IDV blazars showed relatively ＂steeper＂ spectral in- dices than the IDV blazars. Pronounced inter-month variability was also found in two BL Lac objects： J0112＋2244 and J0238＋1636.

关键词： galaxies: active - quasars: general - radio continuum: galaxies -gamma-rays: observations

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Particle-size-dependent upconversion luminescence of NaYf4:Yb,Er nanoparticles in organic solvents and water at different excitation power densities

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Nano Research 2018年第12期11卷 6360-6374页

作者： Marco Kraft Christian Würth Verena Muhr thomas Hirsch Ute Resch-Genger federal Institute for Matefiab Research and Testing (BAM) Division1.2BiophotonicsRichard-Willstaetter-Str.1112489BerlinGermany Institute of Analytical Chemistry Chemo-and BiosensorsUniversity of Regensburg93040RegensburgGermany

A systematic study of the luminescence properties of monodisperse β-NaYf4: 20% Yb3+, 2% Er3+ upconversion nanoparticles (UCNPs) with sizes ranging from 12–43 nm is presented utilizing steady-state and time-resolved fluorometry. Special emphasis was dedicated to the absolute quantification of size- and environment-induced quenching of upconversion luminescence (UCL) by high-energy O–H and C–H vibrations from solvent and ligand molecules at different excitation power densities (P). In this context, the still-debated population pathways of the 4f9/2 energy level of Er3+ were examined. Our results highlight the potential of particle size and P value for color tuning based on the pronounced near-infrared emission of 12 nm UCNPs, which outweighs the red Er3+ emission under “strongly quenched” conditions and accounts for over 50% of total UCL in water. Because current rate equation models do not include such emissions, the suitability of these models for accurately simulating all (de)population pathways of small UCNPs must be critically assessed. furthermore, we postulate population pathways for the 4f9/2 energy level of Er3+, which correlate with the size-, environment-, and P-dependent quenching states of the higher Er3+ energy levels.

关键词： upconversion nanoparticle quenching diameter water cyclohexane

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Issues in the Care and Treatment of HCV/HIV Co-Infection for Key Populations in Resource-Constrained Settings

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Health 2014年第14期6卷 1803-1815页

作者： thomas f. Kresina Robert Lubran H. Westley Clark Center for Substance Abuse Treatment Substance Abuse and Mental Health Services Administration Rockville USA

Globally, the epidemic of hepatitis virus infection is increasing in the context of common viral transmission routes with the Human Immunodeficiency Virus (HIV). Thus, co-infection with both hepatitis virus and HIV is becoming a common occurrence, particularly for key populations. Studies of key populations, people who inject drugs, sex workers, transgendered individuals and men having sex with men, report high levels of illicit drug and/or alcohol use along with limited access to health care and medical treatment. Without the medical management of co-occurring substance use disorders and hepatitis C virus (HCV) infection, a significant proportion of this population with HCV/HIV co-infection will progress to chronic liver disease then subsequently end-stage liver disease. Thus, access to comprehensive care and treatment, including HCV testing with subsequent care and treatment of acute/chronic HCV infection is essential to address the global burden of disease. Increased efforts are needed globally to address the barriers to comprehensive care and treatment for key populations with HCV/HIV co-infection.

关键词： Hepatitis C Infection HIV Substance Abuse Treatment Care and Treatment Key Populations

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Growth of the tropical Pinus kesiya as influenced by climate and nutrient availability along an elevational gradient

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Journal of Plant Ecology 2020年第1期13卷 97-106页

作者： Le Tuan Ho Raimund Schneider frank M.thomas Department of Geobotany University of TrierFaculty of Regional and Environmental SciencesBehringstraße 2154296 TrierGermany Department of forest Resources Management Faculty of ForestryNong Lam University HCMCThu Duc DistrictHo Chi Minh CityVietnam Department of Soil Science University of TrierFaculty of Regional and Environmental SciencesBehringstraße 2154296 TrierGermany

与温带地区相比,人们对在热带山脉中,尤其是热带针叶林中,沿海拔梯度的个体树种生长减少的原因知之甚少。我们的研究目的是检验气候或土壤条件是否会导致在高海拔分布的卡西亚松(Pinus kesiya,一种在南亚和东南亚广泛分布的松树)的生长... 详细信息

与温带地区相比,人们对在热带山脉中,尤其是热带针叶林中,沿海拔梯度的个体树种生长减少的原因知之甚少。我们的研究目的是检验气候或土壤条件是否会导致在高海拔分布的卡西亚松(Pinus kesiya,一种在南亚和东南亚广泛分布的松树)的生长减少。我们对越南中南部山脉中沿海拔梯度约在900~2000米之间的卡西亚松的树干直径增量和其年轮中^(13)C(△^(13)C)的同位素判别进行分析。同时确定其生长与△^(13)C、气候和土壤变量的关系。研究发现,树木的断面积生长量(BAI)与温度或降水之间没有一致的相关关系。相反,沿海拔梯度,我们发现BAI与△^(13)C以及与上层矿质土壤的C/N比和δ^(15)N特征呈显著负相关。BAI与土壤中有效磷(P_(a))和“碱性”阳离子(钙、镁、钾)的浓度呈正相关。我们的结论是,较高海拔下的较低温度会对树木生长产生间接影响,主要通过产生较高的C/N比并降低氮(N)和P矿化率而产生作用,而这些影响因其他负面反馈而进一步受到阻碍。主要包括:降水增加的淋溶作用而导致较低浓度的“碱性”阳离子以及较高海拔土壤矿化的N和P的有效性降低。本研究结果可以进一步解释卡西亚松的最高生长极限以及该物种在其他山区出现的情况。

关键词：树木生态学松树指示年土壤养分稳定同位素

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