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通过实验表征、计算机辅助结构解析和原子模拟对切尔西土壤腐植酸进行三维结构模拟

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腐植酸 2022年第5期 60-75页

作者： Mamadou S.Diallo Andre Simpson Paul Gassman Jean Loup Faulon james h.johnson William A.Goddard Patrick G.hatcher 袁飞巩冠群(译) 加州理工学院贝克曼研究所139-74材料和工艺模拟中心加利福尼亚州帕萨迪纳91125 霍华德大学土木工程系华盛顿特区20059 多伦多大学斯卡伯勒学院物理科学系加拿大多伦多MIC 1A4 太平洋西北国家实验室环境分子科学实验室华盛顿州里奇兰99352 桑迪亚国家实验室计算生物学和进化计算部加利福尼亚州利弗莫尔94551-0969 俄亥俄州立大学化学系俄亥俄州哥伦布43210 中国矿业大学化工学院徐州221116

本文描述了一个用于开发腐植酸(hAs)三维结构模型的完整的实验和计算框架。这种方法结合了实验表征、计算机辅助结构解析(CASE)和原子模拟,生成与hAs的分析数据和热力学/结构特性相一致的所有三维结构模型或这些模型的代表性样本。从元... 详细信息

本文描述了一个用于开发腐植酸(hAs)三维结构模型的完整的实验和计算框架。这种方法结合了实验表征、计算机辅助结构解析(CASE)和原子模拟,生成与hAs的分析数据和热力学/结构特性相一致的所有三维结构模型或这些模型的代表性样本。从元素分析、漫反射傅里叶变换红外光谱、一维/二维~1h和C溶液核磁共振光谱和电喷雾电离四极杆飞行时间质谱(ESI QqTOF MS)中获得的结构数据,结合CASE程序SIGNATURE,生成了切尔西土壤腐植酸(hA)所有的三维结构模型。这些模型随后被用作初始三维结构,进行恒温恒压分子动力学模拟,以估算其体密度和hildebrand溶解度参数。只有少数模型异构体显示出的分子组成和体热力学性质与实验数据一致。这些模型异构体的等摩尔混合物的模拟C核磁共振光谱与切尔西土壤hA的实测光谱相比有较好的一致性。

关键词：土壤多肽和蛋白质分子模拟碳水化合物核磁共振光谱

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The Rising Burden of hepatocellular Carcinoma: Is the Gender Gap Narrowing?

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Journal of Clinical and Translational hepatology 2024年第9期12卷 763-764页

作者： james K.h.ho Prem h.Thurairajah Daniel Q.huang Kristie h.Fan Division of Gastroenterology and hepatology National University HospitalNational University Health SystemSingaporeSingapore

Dear Editors,The landscape of hepatocellular carcinoma(hCC)is continuously *** global trends indicate a significant shift in the epidemiology of hCC from viral-related to non-viral-related ***-associated fatty liver disease has emerged as the fastest-growing contributor to hCC in recent years,due to the increased prevalence of obesity and metabolic risk factors.

关键词： Carcinoma epidemiology obesity

Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： K james Jintu KIM heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT Korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of h,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0h,50h,and *** downstream disturbance frequency varied from 10 hz to 200 hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

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Reducing strain on primary healthcare systems through innovative models of care:the impact of direct access physiotherapy for musculoskeletal conditions—an interrupted time series analysis

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Family Medicine and Community health 2024年第3期12卷 1-12页

作者： james henry Zouch Bjørnar Berg Are hugo Pripp Kjersti Storheim Claire E Ashton-james Manuela L Ferreira Margreth Grotle Paulo h Ferreira Sydney Musculoskeletal health Faculty of Medicine and HealthThe University of SydneySydneyNew South WalesAustralia Centre for Intelligent Musculoskeletal health Oslo Metropolitan University Faculty of Health SciencesOsloNorway Oslo Metropolitan University Faculty of health Sciences OsloNorway Oslo Centre of Biostatistics and Epidemiology Oslo University HospitalOsloNorway Department of Rehabilitation Science and health Technology Oslo Metropolitan University Faculty of Health SciencesOsloNorway Department of Research and Innovation Oslo University Hospital Division of Clinical NeuroscienceOsloNorway Sydney Medical School Kolling InstituteThe University of Sydney Faculty of Medicine and HealthSydneyNew South WalesAustralia The George Institute for Global health SydneyNew South WalesAustralia Department of Research and Innovation Oslo University HospitalOsloNorway Department of Rehabilitation and Technology Oslo Metropolitan University Faculty of Health SciencesOsloNorway Charles Perkins Centre Sydney Musculoskeletal HealthThe University of Sydney Faculty of Medicine and HealthSydneyNew South WalesAustralia

Objectives To evaluate the longitudinal impact of introducing a national,direct access physiotherapy model of care on the rates of primary and secondary care consultations for musculoskeletal(MSK)*** Interrupted time series analysis using segmented linear *** Norway primary care Participants A cohort of 82072 participants was derived from 3 population-based health surveys conducted across separate geographical regions in *** participants surveyed were eligible for inclusion as a national representative sample of the Norwegian *** MSK consultations were linked to the Norwegian Control and Payment of health Reimbursement database and the Norwegian Patient Register using the International Classification of Primary Care diagnostic medical codes L-chapter for MSK conditions and spine related International Classification of Diseases,10th Revision,*** Direct access to physiotherapy model of care introduced nationally in Norway in *** model allowed Norwegians to consult directly with qualified physiotherapists for MSK conditions(eg,back pain,knee osteoarthritis)without the need for a medical referral in order to claim a social security *** outcomes measured Rates of primary care consultations per 10000 population(general practitioner(GP)and physiotherapist consultations)and secondary care(specialist consultations and surgical procedures)measured from 2014 to *** The introduction of the direct access physiotherapy model was associated with an immediate stepped reduction of 391 general practice consultations per 10000 population,(95%CI:−564 to−216),without an associated change in physiotherapy *** analyses suggested there was an associated reduction in physiotherapy consultations for those in the lowest education group of 150 consultations per quarter(95%CI:−203 to−97),70 consultations per quarter in the intermediate education group(95%CI:−115 to−27)and a step

关键词： impact analysis strain

Geohydraulic Investigation of Aquifer Parameters in Abak, Southern Nigeria

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Journal of Geoscience and Environment Protection 2024年第5期12卷 289-301页

作者： Promise james Akpan Akaninyene Okon Akankpo Joseph Gordian Atat johnson Cletus Ibout Emmanuel Bassey Umoren Department of Physics University of Uyo Akwa Ibom Nigeria Department of Physics University of Nigeria Nsukka Nigeria

A geophysical investigation was carried out to characterize aquifer parameters and assess the groundwater condition in Abak, southern Nigeria. Vertical electrical sounding (VES) was carried out using Schlumberger configuration in 10 locations within the area. Both manual and computer interpretation of the resistivity data reveals three to four geoelectric units (laterite topsoil, medium-grained sand, coarse-grained sand, and sandy clay sand) which agrees with the lithologic log from existing boreholes. The aquifer layer was identified along the third formation with resistivity values ranging from 1239 - 5719 Ωm and aquifer depth ranging from 30.2 - 54.8 m. The aquifer thickness ranged from 24.2 - 43.7 m. hydraulic conductivity ranged from 0.1206 m/day - 0.5026 m/day with an average value of 0.29403 m/day. Formation factor ranged from 14.55 - 16.64. Porosity ranged from 15.98% - 22.40%, with an average value of 19.64%. The aquiferous zone falls within the medium/coarse-grained sand. The aquifer is shallow, unconfined, and prolific with a little overburden formation of 13.5 m. The area shows good prospects for groundwater development.

关键词： Electrical Resistivity Porosity Formation Factor hydraulic Conductivity

Integrins and their potential roles in mammalian pregnancy

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Journal of Animal Science and Biotechnology 2024年第1期15卷 1-19页

作者： Gregory A.johnson Robert C.Burghardt Fuller W.Bazer heewon Seo Joe W.Cain Department of Veterinary Integrative Biosciences School of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843‑4459USA Department of Animal Science College of Agriculture and Life SciencesTexas A&M UniversityCollege StationTX 77843‑2471USA

Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the sc

关键词： humans Implantation Integrins Pigs Pregnancy Rodents Sheep

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New Opportunities for Neutrons in Environmental and Biological Sciences

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 179-186页

作者： Alexander Johs Shuo Qian Leighton Coates Brian h.Davison james G.Elkins Xin Gu Jennifer Morrell-Falvey hugh O'Neill Jeffrey M.Warren Eric M.Pierce Kenneth herwig Oak Ridge National Laboratory Oak RidgeTN37831USA

The use of neutron methods in environmental and biological sciences is rapidly emerging and accelerating with the development of new instruments at neutron user *** article,based on a workshop held at Oak Ridge National Laboratory(ORNL),offers insights into the application of neutron techniques in environmental and biological *** highlight recent advances and identify key challenges and potential future research *** include soil and rhizosphere processes,root water dynamics,plant-microbe interactions,structure and dynamics of biological systems,applications in synthetic biology and enzyme engineering,next-generation bioproducts,biomaterials and bioenergy,nanoscale structure,and fluid dynamics of porous materials in *** provide an outlook on emerging opportunities with an emphasis on new capabilities that will be enabled at the Spallation Neutron Source Second Target Station currently under design at *** mission of scientific neutron user facilities worldwide is to enable science using state-of-the-art neutron *** aim to encourage researchers in the environmental and biological research community to explore the unique capability afforded by neutrons at these facilities.

关键词： Neutrons Environment Biology Neutron imaging Neutron scattering Second Target Station(STS)

Synthesis of carbon nitride in potassium hydroxide molten salt for efficient uranium extraction from radioactive wastewater

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 89-99页

作者： Shuang Liu Junhan Luo Daniel-james Maguire Liyuan Zheng Zhe Wang Yuexiang Lu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Nuclear Research Institute for Future Technology and Policy Seoul National UniversitySeoul 08826Republic of Korea Department of Earth Sciences University of CambridgeCambridge CB23EQUK The MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China

Photocatalysis-assisted removal of uranium has been proven as an effective method for the elimination of radioactive pollution from *** this work,carbon nitride materials were synthesized in potassium hydroxide(KOh)molten salt and applied to photocatalytic uranyl *** materials were confirmed to possess the triazine-s-heptazine structure by NMR,XPS and UV-Vis characterization,and exhibited a wider visible light absorption than graphitic carbon nitride(g-C_(3)N_(4)).The photocatalytic activity of the carbon nitride materials was tailored by varying the precursor mass *** carbon nitride obtained at 80%melamine as precursor(K-CN-80)exhibited the highest photocatalytic extraction ability and its photocatalytic reaction rate is 6.6 times faster than that of g-C_(3)N_(4).The influence of sacrificial agents was studied and the results showed that triethanolamine inhibited U(Ⅵ)photoreduction,but methanol can accelerate U(Ⅵ)photoreduction by consuming photogenerated *** unary KOh molten salt synthesis method has exceptional potential applications in the preparation of carbon nitrides,and the obtained products showed potential in extracting U(Ⅵ)from aqueous solutions for use in nuclear fuel industry and for U(Ⅵ)environmental pollution cleanup.

关键词： Uranium Carbon nitride Molten salt Photocatalysis Radioactive wastewater

Facilitated Prediction of Micropollutant Degradation via UV-AOPs in Various Waters by Combining Model Simulation and Portable Measurement

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Engineering 2024年第6期37卷 87-95页

作者： Yanyan huang Mengkai Li Zhe Sun Wentao Li james R.Bolton Zhimin Qiang Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Department of Civil and Environmental Engineering University of AlbertaEdmontonAB T6G 1H9Canada State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The degradation of micropollutants in water via ultraviolet(UV)-based advanced oxidation processes(AOPs)is strongly dependent on the water *** reactive radicals(RRs)formed in UV-AOPs have different reaction selectivities toward water matrices and degradation efficiencies for target ***,process selection and optimization are *** study developed a facilitated prediction method for the photon fluence-based rate constant for micropollutant degradation(K′_(p,MP))in various UV-AOPs by combining model simulation with portable *** methods for measuring the scavenging capacities of the principal RRs(RRSCs)involved in UV-AOPs(i.e.,hO^(·),SO_(4)^(·-),and Cl^(·))using a mini-fluidic photoreaction system were *** simulation models consisted of photochemical,quantitative structure–activity relationship,and radical concentration steady-state approximation *** RRSCs were determined in eight test waters,and a higher RRSC was found to be associated with a more complex water ***,by taking sulfamethazine,caffeine,and carbamazepine as model micropollutants,the k′_(p,MP) values in various UV-AOPs were predicted and further verified experimentally.A lower k′_(p,MP) was found to be associated with a higher RRSC for a stronger RR competition;for example,k′_(p,MP) values of 130.9 and 332.5 m^(2) einstein^(–1),respectively,were obtained for carbamazepine degradation by UV/h_(2)O_(2) in the raw water(RRSC=9.47×10^(4) s^(-1))and sand-filtered effluent(RRSC=2.87×10^(4) s^(-1))of a drinking water treatment *** developed method facilitates process selection and optimization for UV-AOPs,which is essential for increasing the efficiency and cost-effectiveness of water treatment.

关键词： UV-AOPs Micropollutant degradation Reactive radicals Water matrix Model simulation