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Assessment of mercury(II) bioavailability using a bioluminescent bacterial biosensor: Practical and theoretical challenges

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Journal of Environmental Sciences 2010年第8期22卷 1137-1143页

作者： Paulo R G Barrocas william m Landing Robert J m Hudson Department of Sanitation and Environmental Health National School of Public Health Oswaldo Cruz Foundation Department of Oceanography Florida State University. Tallahassee Department of Natural Resources and Environmental Sciences University of Illinois

Critical methodological challenges in the microbial biosensor approach to assessing Hg（II） bioavailability were evaluated from the perspective of analytical chemists. The main challenge stems from the fact that the chemical speciation of Hg（II） in natural waters exerts a major control on its bioavailability, yet its natural complexation equilibria are extensively altered during conventional bioassays. New data, obtained using a bioluminescent Hg（II）-biosensor, that illustrate these challenges are presented and potential solutions proposed.

关键词： mercury bioavailability biosensor chemical speciation bioluminescent

Structural Controls and Predictive mapping of Tin, Niobium and Tantalum mineralization Associated with the mayo Darlé Stanniferous Granitoids;Contributions of Geostatistics

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Journal of Geoscience and Environment Protection 2024年第1期12卷 180-210页

作者： Bah-Yero Liman Ngounouno Ismaïla mbowou Gbambié Isaac Bertrand Alpha Baster Kenfack Fokem André william Boroh Amadou Diguim Kepnamou Department of Earth Sciences Faculty of Science University of Ngaoundéré Ngaoundéré Cameroon Department of mining Geology School of Geology and Mining and Engineering University of Ngaoundéré Meiganga Cameroon Department of Earth Sciences Faculty of Science University of Garoua Garoua Cameroon

The aim of this study of the spatial dispersion of tin, niobium and tantalum mineralization associated with the mayo Darlé granitoids was to produce prospecting guides through predictive maps of Sn, Nb and Ta in the region. It was based on a database (in appendix) obtained after analysis of rock samples (greisens and quartz veins) collected in the field, using a portable X-ray fluorescence (XRF) spectrometer. Two approaches were used: 1) structural studies in the field using the directions of veins and fractures 2) the use of variographic maps, an essential element in geostatistics for determining directional anisotropies. A joint synthesis of the modelling results shows that tin, tantalum and niobium mineralization at mayo Darlé is concentrated along strike intervals N315E to N320E, with mineralization also occurring along strike N35E for high-grade Sn, medium-grade Ta and low-grade Nb. In short, mineral concentrations disperse progressively in space: positively from east to west for tantalum and niobium, and inversely for tin.

关键词： mayo Darlé Tin Niobium Tantalum Geostatistics mapping

Social and Economic Considerations for Creating Sustainable Climate Change Haven Communities

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Journal of Environmental Protection 2024年第1期15卷 76-93页

作者： Elizabeth C. Hirschman william Bourgin Angel Castilla Caitlin Glover Caitlyn Justice manuel munoz Braydon Thompson Justin Snider Olivia Toomer Department of Business and Economics University of Virginia-Wise Wise USA

As Climate Change Haven Communities are constructed across the Northern Hemisphere, it will be necessary to attract two types of migrants to populate them. The first group consists of professionals and companies in eco-sustainable businesses, such as law firms, insurance companies, investment firms, banking, technological innovation, mass media, medical research and pharmaceutical research. The second group will consist of persons engaged in organic/eco-sustainable agriculture whose crops and animal husbandry practices can be transferred successfully to Climate Change Haven regions. The present research focuses on the social and economic variables that must be taken into account to insure that each new Climate Change Haven Community becomes successfully integrated with the local population and forms a cohesive, harmonious social structure. Examples are given from the United States, France, Spain, Portugal and Italy.

关键词： Climate Change Haven Community Sustainability Organic/Eco Farming Internal migration Social Integration

Floristic Composition, Population Structure, and Recruitment Status of Plant Species: A Case Study of Farmer-managed Natural Regeneration Practices in Arid and Semi-Arid Lands in Kenya

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Open Journal of Forestry 2024年第2期14卷 141-154页

作者： Simon Kosgei Choge Samson Okoth Ojunga Dub Isacko Dokata william Kimen Chepkirui Justus musau Faith milkah muniale Ivan Kiplagat Kiptui Kenya Forestry Research Institute-Rift Valley Eco-Region Research Program Marigat Kenya Kenya Forestry Research Institute-Lake Victoria Eco-Region Research Program Kisumu Kenya Kenya Forestry Research Institute-Rift Valley Eco-Region Research Program Londiani Kenya CRIFSUP Project World Vision Kenya Nairobi Kenya

The technique of Farmer managed Natural Regeneration (FmNR) is being promoted as a cost-effective approach for restoring degraded arable dry lands. Its effectiveness has been observed in many countries across the globe, where it is a traditional practice, and is now being encouraged across the African continent. This study aimed to evaluate the impact of FmNR on floristic Composition, Vegetation Structure, and Regeneration Status of woody Plant Species in the severely degraded Central Rift, Kenya. The study systematically assessed how FmNR influenced species composition, vegetation structure and regeneration status from two sample plots involved in FmNR practices. Transect lines and quadrats methods were utilized to collect data, specifically regarding the floristic composition, vegetation structure, and regeneration status of woody plant species. Quadrats and sub-quadrats of varying sizes (10 m by 10 m, 5 m by 5 m, and 1 m by 1 m) were nested along the transect lines for data collection. Furthermore, measurements of tree growth and development, including root collar diameter, diameter at breast height (D130) and heights within the study blocks, were taken. The data was then analyzed using R-software. Results showed a marked progressive increase in numbers of trees, saplings, seedlings, shrubs and herbs in all FmNR sites and reductions in all non-FmNR sites. The study advocates for widespread promotion of the FmNR practice both as an environmental conservation and restoration strategy.

关键词： Farmer managed Natural Regeneration FmNR Floristic Composition Vegetation Structure Regeneration Biodiversity

Prevalence of Work-Aggravated Asthma among Bakery Workers in Abidjan (Cote d’Ivoire)

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Health 2024年第3期16卷 204-217页

作者： Loukou Leandre Konan Esme marie Laure Essis Brou michel Kouassi marius Kedote Julius Fobil william Yavo Ossey Bernard Yapo Issaka Tiembre National Institute of Public Health Abidjan Cote d’Ivoire Interuniversity Doctoral Program Cotonou Benin medical Sciences Training and Research Unit Department of Public Health and Biostatistics Felix Houphouet Boigny University Abidjan C&#244te d’Ivoire Global Environmental Occupational Health (GEOHealth) Accra Ghana UFR of Pharmaceutical and Biological Sciences Department of Public Health Felix Houphou&#235t Boigny University Abidjan Cote d’Ivoire Nangui Abrogoua University Abidjan C&#244te d’Ivoire National Institute of Public Hygiene Abidjan C&#244te d’Ivoire

Introduction: Work-aggravated asthma is pre-existing or concomitant asthma whose symptoms are aggravated by the work environment. The aim of this study was to determine the prevalence of this pathology and its associated factors among bakery workers in Abidjan. materials and methods: This descriptive and analytical cross-sectional study was conducted over a period of four (4) months from 18 December 2019 to 18 April 2020. Two questionnaires were used, one on employees and the other on the indoor environment of bakeries. In addition, a spirometry test was performed on all bakery workers. Statistical analysis was performed using stata 15.1 software. Results: A total of 599 bakery employees, including bakers (59.73%), sales assistants/ cashiers (23.52%), cleaners (6.34%) and administrative staff (10.18%), were investigated. The mean age was 30.8 ± 8 years, with a sex ratio (m/F) = 2.2. Asthma symptoms were found in 95 (15.86%) employees, of whom 74 (77.9%) had work-related asthma and 11 (14.9%) had asthma aggravated by work. The factors associated with work-aggravated asthma were personal or family history of allergy or atopy [ORa = 3.75;CI95%: 1.56 - 8.93;p = 0.003], exposure to dust [ORa = 5.01;CI95%: 1.43 - 7.50;p = 0.011] and humidity level (60% - 70%) [ORa = 1.80;CI 95%: 0.99 - 3.28;p = 0.05]. Conclusion: Work-aggravated asthma is a reality in bakeries in Abidjan, with an estimated prevalence of 14.9%. Two of the three factors associated with this condition suggest a link with indoor air pollution. Combating air pollution in these establishments must therefore be a priority for the relevant authorities, in order to provide employees with a working environment that protects their health.

关键词： Work-Aggravated Asthma Occupational Asthma Work-Related Asthma Bakeries Abidjan Ivory Coast

Stromal cell decidualization and embryo implantation: a vulnerable step leading to successful pregnancy

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Reproductive and Developmental medicine 2024年第2期8卷 101-110页

作者： Luhan Jiang Sudini R.Fernando Suranga P.Kodithuwakku Dandan Cao william S.B.Yeung Kai-Fai Lee Department of Obstetrics and Gynaecology School of Clinical MedicineLKS Faculty of MedicineThe University of Hong KongHong Kong SAR 999077China Department of Animal Science Faculty of Animal Science&Export AgricultureUva Wellassa UniversityBadulla 50000Sri Lanka Department of Animal Science Faculty of AgricultureUniversity of PeradeniyaPeradeniya 20400Sri Lanka Shenzhen Key Laboratory of Fertility Regulation.The University of Hong Kong-Shenzhen Hospital Shenzhen 518053China

Endometrial stromal cell decidualization is a crucial step in endometrial remodeling during *** is controlled by orchestrated ovarian hormones,followed by the activation of various downstream signaling *** evidence has shown multiple functions of decidualized endometrial stromal cells during embryo implantation,including tissue remodeling,antioxidative stress,angiogenesis,and immune *** distinct secretomes of decidualized stromal cells also reveal their intensive interactions with epithelial,endothelial,and immune ***,aberrant decidualization leads to pregnancy failures,such as recurrent pregnancy loss and repeated implantation *** review aimed to provide an overview of the molecular mechanisms underlying the divergent functions of decidualized endometrial stromal cells and their potential clinical ***,the use of single-cell RNA sequencing data further enhances our understanding of these biological *** review discusses decidualization-related signaling pathways that serve as potential therapeutic targets for treating implantation failure in in vitro fertilization and provides novel approaches to investigate the underlying causes of female infertility.

关键词： Endometrial stromal cell Decidualization Embryo implantation Recurrent pregnancy loss Repeated implantation failure

地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示（英文）

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Science Bulletin 2024年第1期 97-102页

作者：王瑞邬绍宸 Roberto F.Weinberg william J.Collins Peter A.Cawood State Key Laboratory of Geological Processes and mineral Resources Institute of Earth Sciences China University of Geosciences Frontiers Science Center for Deep-time Digital Earth China University of Geosciences (Beijing) School of Earth Atmosphere and Environment Monash University The Institute for Geoscience Research Curtin University

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state, expressed as ΔFmQ, through Earth’s history. Those from I-type rocks, which comprise mantle and crustal igneous protoliths, including tonalite–trondhjemite–granodiorites(TTGs), generally have a high oxidation state(ΔFmQ > 0). In contrast, zircons from igneous rocks derived from supracrustal source rocks(S-type) are commonly reduced(ΔFmQ m the Gaussian-Kernel-Density-Estimation, we use the maximum likelihood estimation(mLE) to distinguish Stype from I-type zircons through Earth’s history using zircon redox. Voluminous S-type magma production shows a ca. 600 ma cyclicity that is closely related to the supercontinent cycle. We link a cyclic drop in redox values after 2.6 Ga to periodic S-type magma generation associated with burial and melting of metasedimentary rocks during supercontinent assembly and amalgamation. The ΔFmQ of the detrital zircons rise at ～3.5 Ga followed by a consistent average ΔFmQ > 0 over the last 3 Ga. Given that the redox state of magmas is independent of crustal thickness and silica variation, and elevated values are likely more closely related to tectonic setting, we suggest that the consistent average ΔFmQ > 0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction zones. The more reduced magmas associated with sedimentary sources, became established at 2.6 Ga, presumably in response to continental rocks rising above sealevel, and follow peaks of productivity associated with the supercontinent cycle.

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Canonical and noncanonical Wnt signaling: multilayered mediators, signaling mechanisms and major signaling crosstalk

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Genes & Diseases 2024年第1期11卷 103-134页

作者： Kevin Qin michael Yu Jiaming Fan Hongwei Wang Piao Zhao Guozhi Zhaoo Wei Zeng Connie Chen Yonghui Wang Annie Wang Zander Schwartz Jeffrey Hong Lily Song william Wagstaff Rex C.Haydon Hue H.Luu Sherwin H.Ho Jason Strelzow Russell R.Reid Tong-Chuan He Lewis L.Shi Chicago medical School Rosalind Franklin University of Medicine and ScienceNorth ChicagoIL 60064USA molecular Oncology Laboratory Department of Orthopaedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA ministry of Education Key Laboratory of Diagnostic medicine and Department of Clinical BiochemistryThe School of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Departments of Orthopaedic Surgery and Urology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Interventional Neurology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguanGuangdong 523475China Department of Clinical Laboratory medicine Shanghai Jiaotong University School of MedicineShanghai 200000China School of Biomedical Engineering Vanderbilt UniversityNashvilleTN 37235USA Laboratory of Craniofacial Biology and Development Department of Surgery Section of Plastic SurgeryThe University of Chicago Medical CenterChicagoIL 60637USA

Wnt signaling plays a major role in regulating cell proliferation and *** Wnt ligands are a family of 19 secreted glycoproteins that mediate their signaling effects via binding to Frizzled receptors and LRP5/6 coreceptors and transducing the signal either throughβ-catenin in the canonical pathway or through a series of other proteins in the nonca-nonical *** of the individual components of both canonical and noncanonical Wnt signaling have additional functions throughout the body,establishing the complex interplay between Wnt signaling and other signaling *** crosstalk between Wnt signaling and other pathways gives Wnt signaling a vital role in many cellular and organ ***-regulation of this system has been implicated in many diseases affecting a wide array of organ systems,including cancer and embryological defects,and can even cause embryonic *** complexity of this system and its interacting proteins have made Wnt signaling a target for many therapeutic ***,both stimulatory and inhibitory treatments come with potential risks that need to be *** review synthesized much of the current knowl-edge on the Wnt signaling pathway,beginning with the history of Wnt *** thoroughly described the different variants of Wnt signaling,including canonical,noncanonical Wnt/PCP,and the noncanonical Wnt/Ca2+*** description involved each of its components and their involvement in other cellular ***,this review explained the various other pathways and processes that crosstalk with Wnt signaling.

关键词： β-catenin Canonical Wnt Noncanonical Wnt Signal transduction Signaling crosstalk

Predictive value of hypo-osmotic swelling test to identifyviable non-motile sperm

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Asian Journal of Andrology 2003年第3期5卷 209-212页

作者： william m.Buckett University of Liverpool and the Reproductive medicine Unit Liverpool Women's Hospital Liverpool UK

Aim: To determine the predictive value of the hypo-osmotic swelling (HOS) test to identify viable, non-motile sperm. methods: Semen samples from 20 men with severe asthenozoospermia underwent traditional seminal analysis, eosin-nigrosin (EN) staining and the HOS test. A further EN stain was then performed on a HOS pre-treated aliquot and a total of 2000 further sperm examined. Results: The median sperm density was 5.1 million/mL (IQR 4.3-13.1) and the median motility was 3.0 % (IQR 0-7). Seven samples showed complete asthenozoospermia. Initial EN staining showed 59 % viability (range 48-69) despite the poor standard parameters and 47 % (range 33-61) in the complete asthenozoospermia subgroup. The HOS test showed 49.9 % reacted overall (range 40-59) and 41.7 % (range 22-61) in the complete asthenozoospermia subgroup. The combined HOS/EN stain showed the positive predictive value of the HOS test to identify viable sperm was 84.2 % overall and 79.7 % in the complete asthenozoospermia subgroup. Conclusion: The HOS test can effectively predict sperm viability in patients with severe and complete asthenozoospermia.

关键词： azoospermia sperm spermmotility hypo-osmotic swelling (HOS) test sperm viability predictive value