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Role of complex organic arsenicals in food in aggregate exposure to arsenic

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journal of Environmental Sciences 2016年第11期28卷 86-96页

作者： David j.thomas Karen Bradham Pharmacokinetics Branch Integrated Systems Toxicology Division National Health and Environmental Effects Research Laboratory Offilce of Research and Development U.S. Environmental Protection Agency Research Triangle Parle NC 27709 USA Public Health Chemistry Branch Exposure Methods and Measurements Division National Exposure Research Laboratory Offilce of Researchand Development U.S. Environmental Protection Agency Research Triangle Park NC 27709 USA

For much of the world＇s population, food is the major source of exposure to *** to this non-essential metalloid at relatively low levels may be linked to a wide range of adverse health effects. Thus, evaluating foods as sources of exposure to arsenic is important in assessing risk and developing strategies that protect public health. Although most emphasis has been placed on inorganic arsenic as human carcinogen and toxicant, an array of arsenic-containing species are found in plants and animals used as foods. Here,we 2evaluate the contribution of complex organic arsenicals（arsenosugars, arsenolipids,and trimethylarsonium compounds） that are found in foods and consider their origins,metabolism, and potential toxicity. Commonalities in the metabolism of arsenosugars and arsenolipids lead to the production of di-methylated arsenicals which are known to exert many toxic effects. Evaluating foods as sources of exposure to these complex organic arsenicals and understanding the formation of reactive metabolites may be critical in assessing their contribution to aggregate exposure to arsenic.

关键词： Arsenic Arsenobetaine Arsenolipids Arsenosugars

Free-space interferometer design for optical frequency dissemination and out-of-loop characterization below the 10^(-21)-level

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Photonics Research 2023年第6期11卷 1113-1124页

作者： thomas jÜRSS GESINE GROSCHE SEBASTIAN KOKE Physikalisch-Technische Bundesanstalt 38116 BraunschweigGermany

For improving the performance of optical frequency dissemination and the resolution of its out-of-loop(OOL)characterization,we investigate a compact free-space interferometer design in which a monolithic assembly forms the reference *** interferometer designs are realized,and their environmental sensitivity is analyzed based on the properties of the materials *** elucidate that in these designs the temperature sensitivities of the out-of-loop signal paths are greater than for the reference *** the estimated temperature-variation-induced frequency transfer errors are observed to be the relevant limitation,the out-of-loop characterization signal can be regarded as a trustworthy upper limit of the frequency transfer error to a remote *** demonstrate a fractional frequency transfer uncertainty and OOL characterization resolution of≤2.7×10^(-21)over many measurement *** a value of(0.23±1.07)×10^(-22)the weighted mean offset is significantly below the best reported results so far.

关键词： characterization fractional limit

A human monoclonal antibody neutralizes SARS-CoV-2 Omicron variants bytargeting the upstream region of spike protein HR2 motif

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hLife 2024年第3期2卷 126-140页

作者： Hang Su jun Zhang Zhenfei Yi Sajid Khan Mian Peng Liang Ye Alan Bao Han Zhang Guangli Suo Qian Li Housheng Zheng Dandan Wu thomas j.Kipps Lanfeng Wang Zhenghong Lin Suping Zhang Shenzhen Key Laboratory of Precision Medicine for Hematological Malignancies Guangdong Key Laboratory for Genome Stability andHuman Disease PreventionDepartment of PharmacologySchool of Basic Medical SciencesBase for International Science and TechnologyCooperation:Carson Cancer Stem Cell Vaccines R&D CenterInternational Cancer CenterShenzhen University Medical SchoolShenzhenUniversityGuangdongChina School of Life Sciences Chongqing UniversityChongqingChina The Center for Microbes Development and HealthCAS Key Laboratory of Molecular Virology&ImmunologyShanghai Institute of Immunityand InfectionChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghaiChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina Department of Critical Care Medicine Shenzhen Luohu People’s HospitalGuangdongChina University of California BerkeleyCaliforniaUSA Xenta Biomedical Science Co. LtdGuangdongChina CAS Key Laboratory of Nano-Bio Interface Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesJiangsuChina Center of Novel Therapeutics University of CaliforniaSan DiegoCaliforniaUSA

The continuous emergence of new severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants meansthere is a need to explore additional strategies to develop broad-spectrum vaccines or therapeutics for individuals remaining at risk of coronavirus disease 2019(COVID-19).Neutralizing monoclonal antibody(mAb)that binds to theconserved S2 subunit of the SARS-CoV-2 spike(S)protein alone,or in combination with mAb that binds to the receptor-binding domain(RBD)of S protein,might be effective in eliciting protection from infection by a variety of SARS-CoV2 *** high-throughput single-cell immunoglobulin sequencing of B cells from COVID-19-convalescent donors,we identified a high-affinity S2-specific mAb-39,that could inhibit original SARS-CoV-2 strain,Omicron BA.1,BA.2.86,BA.4,BA.5,and EG.5.1 S protein-mediated membrane fusion,leading to the neutralization of these ***,mAb-39 could also improve the neutralizing activity of anti-RBD antibody against the highlyneutralization-resistant Omicron *** docking and point mutation analyses revealed that mAb-39 recognized epitopes within the conserved upstream region of the heptad repeat 2(HR2)motif of the S2 ***,these findings demonstrate that targeting the conserved upstream region of the HR2 motif(e.g.,using mAbs)provides anovel strategy for preventing the infection of SARS-CoV-2 and its variants.

关键词： coronavirus disease 2019(COVID-19) severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variants monoclonal antibody upstream region of heptad repeat 2(HR2) immunoglobulin repertoiresequencing

Surgical techniques for the management of male infertility

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Asian journal of Andrology 2012年第1期14卷 94-102,177页

作者： Natalya A Lopushnyan thomas j Walsh Department of Urology University of Washington Seattle WA 98195 USA

Evaluation and surgical treatment of male infertility has evolved and expanded, now leading to more precise diagnoses and tailored treatments with diminished morbidity and greater success. Surgeries for male infertility are divided into four major categories：（i） diagnostic surgery; （ii） surgery to improve sperm production; （iii） surgery to improve sperm delivery; and （iv） surgery to retrieve sperm for use with in vitrofertilization and intracytoplasmic sperm injection （IVF-ICSI）. While today we are more successful than ever in treating male infertility, pregnancy is still not always achieved likely due to factors that remain poorly understood. Clinicians treating infertility should advocate for couple-based therapy, and require that both partners have a thorough evaluation and an informed discussion before undergoing specific surgical therapies.

关键词： male infertility testis varicocele

Foreword： varicocele - unraveling the enigma

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Asian journal of Andrology 2016年第2期18卷 159-160页

作者： Anthony j thomas Cleveland Clinic Lerner College of Medicine of CaseWestern University Cleveland Ohio USA.

It was more than 40 years ago, as a first-year Urology resident, that I performed my first varicocele ligation （a palomo procedure under the watchful eye and able hands of my staff physician. I dutifully read all I could the night before the procedure and became familiar with the names of Barfield, Macomber and Sanders, Tulloch, MacLeod, Ivanissevich, Palomo, Amelar and Dubin and others who had written about varicoceles being associated with abnormal semen parameters and a potentially surgically correctable cause of male infertility.

关键词： Foreword varicocele - unraveling the enigma

Synthesis and electronic properties of expanded 5-(hetero)arylthien-2-yl substituted 3-ethynyl quinoxalines with AIE characteristics

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Science China Chemistry 2018年第8期61卷 909-924页

作者： Franziska K.Merkt thomas j.j.Müller Institute of Organic Chemistry and Macromolecular Chemistry Heinrich Heine University Düsseldorf

Expanded 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes with variable substitution pattern on the peripheral thiophene ring were synthesized in moderate to very good yields by Suzuki and Buchwald-Hartwig coupling of the corresponding brominated 3-ethynyl quinoxalines. Dumbbell-shaped bis(thienyl 3-ethynyl quinoxalines) are also accessible by the Suzuki protocol. The photophysical properties were investigated by UV and fluorescence spectroscopy. Most of the obtained compounds display fluorescence in solution and some of them also in the solid state. Additionally, tuning of the emission color of the quinoxaline based chromophores can be conveniently accomplished by the remote substituent group. The determined absorption and emission maximum as well as the Stokes shifts strongly correlate with Hammett σp+parameters. Besides,photophysical properties of selected derivatives in the solid state, biphasic solutions, and PMMA films, along with their relationships, are comparatively investigated. Moreover, two 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes are aggregation induced emission(AIE) chromophores indicated by restriction of molecular motions. A covalently restricted 3-ethynyl quinoxaline supports that the inhibition of molecular rotation is responsible for the significant enhancement of fluorescence in acetonitrile/water mixtures.

关键词： absorption aggregation induced emission cross-coupling fluorescence heterocycles palladium

Quantitative model evaluation of organic carbon oxidation hypotheses for the Ediacaran Shuram carbon isotopic excursion

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Science China Earth Sciences 2017年第12期60卷 2118-2127页

作者： SHI Wei LI Chao thomas j.ALGEO State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Department of Geology University of Cincinnati

The largest global carbon-cycle perturbation in Earth history was recorded in the Ediacaran—a persistent negative shift in the global marine dissolved inorganic carbon(DIC) reservoir that lasted for ~25–50 million years, with a nadir of –12‰(i.e.,the Shuram Excursion, or SE). This event is considered to have been a result of full or partial oxidation of a large dissolved organic carbon(DOC) reservoir, which, if correct, provides evidence for massive DOC storage in the Ediacaran ocean owing to an intensive microbial carbon pump(MCP). However, this scenario was recently challenged by new hypotheses that relate the SE to oxidization of recycled continentally derived organic carbon or hydrocarbons from marine seeps. In order to test these competing hypotheses,this paper numerically simulates changes in global carbon cycle fluxes and isotopic compositions during the SE, revealing that:(1) given oxygen levels in the Ediacaran atmosphere-ocean of ≤40% PAL, the recycled continental organic carbon hypothesis and the full oxidation of oceanic DOC reservoir hypothesis are challenged by the atmospheric oxygen availability which would have been depleted in 4 and 6 million years, respectively;(2) the marine-seep hydrocarbon oxidation hypothesis is challenged by the exceedingly large hydrocarbon fluxes required to sustain the SE for >25 Myr; and(3) the heterogeneous(partial) DOC oxidation hypothesis is quantitatively able to account for the SE because the total amount of oxidants needed for partial oxidation(<50%)of the global DOC reservoir could have been met.

关键词： Carbon isotope Shuram Excursion Dissolved organic carbon Atmospheric oxygen Oceanic oxidation

The impact of macroalgae on mean and turbulent flow fields

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journal of Hydrodynamics 2015年第3期27卷 427-435页

作者： thomas Robert E. MCLELLAND Stuart j. Department of Geography Environment and Earth Sciences University of Hull

In this paper, we attempt to quantify the mean and turbulent flow fields around live macroalgae within a tidal inlet in Norway. Two Laminaria digitata specimens - 0.50 m apart were selected for detailed study and a profiling ADV was used to collect 45 velocity profiles, each composed of up to seven 0.035 m-high profiles collected for 240 s at 100 Hz, at a streamwise spacing of 0.25 m and cross-stream spacing of 0.20 m. To quantify the impact of the macroalgae, measurements were repeated over a sparser grid after the region had been completely cleared of algae and major roughness elements.

关键词： dealiasing laminaria digitata turbulence vectrino profiler velocity profile

Microbial influences on paleoenvironmental changes during the Permian-Triassic boundary crisis

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Science China Earth Sciences 2014年第6期57卷 965-975页

作者： LUO GenMing XIE ShuCheng LIU Deng thomas j. ALGEO State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

The biosphere interacts and co-evolves with natural *** is known about the biosphere’s response to ancient environmental perturbations,but less about the biosphere’s influences on environmental change through earth ***,we discuss the roles of microbes in environmental changes during the critical Permian-Triassic(P-Tr)transition and present a perspective on future geomicrobiological *** biomarkers,stable isotopic compositions of carbon,nitrogen and sulfur,and mineralogical investigations have shown that a series of microbial functional groups might have flourished during the P-Tr transition,including those capable of sulfate reduction,anaerobic H2S oxidation,methanogenesis,aerobic CH4oxidation,denitrification,and nitrogen *** microbes may have served to both enhance and degrade the habitability of the Earth-surface environment during this *** integrated microbial roles have enabled the Earth’s exosphere to be a self-regulating system.

关键词： microbial functional groups (MFGs) Permian Triassic mass extinction co-evolution