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Possible Habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,sO,and C^(18)O in the Initial Conditions of High-mass star Formation

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

作者： quan-Ling Cui Chuan-Peng Zhang Jun-Jie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China College of science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted fro... 详细信息

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)such conditions,many molecules become depleted from the gas phase by freezing out onto dust ***,the N-bearing and deuterated species could remain gaseous under these extreme conditions,suggesting that they may serve as ideal *** this paper,using the Plateau de Bure Interferometer and Very Large Array observations at 1.3 mm,3.5 mm,and 1.3 cm,we investigate the possible habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,sO,and C^(18)O in eight massive precluster and protocluster clumps G18.17,G18.21,G23.97N,G23.98,G23.44,G23.97s,G25.38,and *** found that the NH3cores are in good agreement with the 3.5 mm peak emission,but the NH_(3)is much more extended than the 3.5 mm emission *** sO distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any sO emission in the four earliest star formation sources.C^(18)O is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the NH_(2)D cores are mainly located in the temperature range of 13.0-20.0 K,and the NH_(2)D lines may be strongly depleted above 20 K.

关键词： galaxies:star formation techniques:interferometric methods:observational

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severe pediatric COVID‑19:a review from the clinical and immunopathophysiological perspectives

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World Journal of Pediatrics 2024年第4期20卷 307-324页

作者： Yi‑Kan sun Can Wang Pei‑quan Lin Lei Hu Jing Ye Zhi‑Gang Gao Ru Lin Hao‑Min Li Qiang shu Li‑su huang Lin‑Hua Tan Children's Hospital Zhejiang University School of MedicineHangzhou 310052China The second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310030China surgical Intensive Care Unit Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of General surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiopulmonary and Extracorporeal Life support Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Clinical Data Center Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiac surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China National Clinical Research Center for Child Health Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Infectious Diseases Children’s HospitalZhejiang University School of MedicineHangzhou 310052China

Background Coronavirus disease 2019(COVID-19)tends to have mild presentations in ***,severe and critical cases do arise in the pediatric population with debilitating systemic impacts and can be fatal at times,meriting further attention from ***,the intricate interactions between the pathogen virulence factors and host defense mechanisms are believed to play indispensable roles in severe COVID-19 pathophysiology but remain incompletely *** sources A comprehensive literature review was conducted for pertinent publications by reviewers independently using the PubMed,Embase,and Wanfang *** keywords included“COVID-19 in children”,“severe pediatric COVID-19”,and“critical illness in children with COVID-19”.Results Risks of developing severe COVID-19 in children escalate with increasing numbers of co-morbidities and an unvaccinated *** respiratory distress stress and necrotizing pneumonia are prominent pulmonary manifestations,while various forms of cardiovascular and neurological involvement may also be *** immunological processes are implicated in the host response to COVID-19 including the type I interferon and inflammasome pathways,whose dysregulation in severe and critical diseases translates into adverse clinical *** inflammatory syndrome in children(MIs-C),a potentially life-threatening immune-mediated condition chronologically associated with COVID-19 exposure,denotes another scientific and clinical conundrum that exemplifies the complexity of pediatric *** the considerable dissimilarities between the pediatric and adult immune systems,clinical trials dedicated to children are lacking and current management recommendations are largely adapted from adult *** severe pediatric COVID-19 can affect multiple organ *** dysregulated immune pathways in severe COVID-19 shape the disease course,epitomize the vast functional diversity of the

关键词： Immunopathophysiology MIs-C Pediatric critical care severe pediatric COVID-19

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Anti-Tumor and Anti-Diabetic Effects of sarsasapogenin

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Medicinal Plant 2024年第1期15卷 59-61页

作者： Mingxinzhi WANG Jingchao WANG quan quan Xichun huang Xinyu LIU Chenghao JIN College of Life science and Biotechnology Heilongjiang Bayi Agricultural UniversityDaqing 163319China

In this paper,the pharmacological effects and molecular mechanisms of sarsasapogenin,such as anti-oxidant,anti-inflammatory and anti-diabetic effects,are reviewed in order to provide a theoretical basis for the subseq... 详细信息

关键词： sarsasapogenin Anti-tumor Anti-diabetic Anti-inflammatory

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A post-modification strategy to precisely construct dual-atom sites for oxygen reduction electrocatalysis

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Journal of Energy Chemistry 2024年第3期90卷 511-517,I0012页

作者： Juan Wang Xinyan Liu Chang-Xin Zhao Yun-Wei song Jia-Ning Liu Xi-Yao Li Chen-Xi Bi Xin Wan Jianglan shui Hong-Jie Peng Bo-quan Li Jia-Qi huang school of Materials science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina school of Materials science and Engineering Beihang UniversityBeijing 100191China

Dual-atom catalysts(DACs) afford promising potential for oxygen reduction electrocatalysis due to their high atomic efficiency and high intrinsic ***,precise construction of dual-atom sites remains a *** this work,a post-modification strategy is proposed to precisely fabricate DACs for oxygen reduction ***,a secondary metal precursor is introduced to the primary single-atom sites to introduce direct metal-metal interaction,which ensures the formation of desired atom pair structure during the subsequent pyrolysis process and allows for successful construction of *** as-prepared FeCo-NC DAC exhibits superior oxygen reduction electrocatalytic activity with a half-wave potential of 0,91 V *** hydrogen ***-air batteries equipped with the FeCo-NC DAC demonstrate higher peak power density than those with the Pt/C *** importantly,this post-modification strategy is demonstrated universal to achieve a variety of dual-atom *** work presents an effective synthesis methodology for precise construction of catalytic materials and propels their applications in energy-related devices.

关键词： Dual-atom catalysts Electrocatalysis Oxygen reduction reaction Post-modification Zinc–air batteries

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Transfer matrix method for free and forced vibrations of multi-level functionally graded material stepped beams with different boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 983-1000页

作者： Xiaoyang sU Tong HU Wei ZHANG Houjun KANG Yunyue CONG quan YUAN school of Civil Engineering and Architecture Guangxi UniversityNanning 530004China scientific Research Center of Engineering Mechanics Guangxi UniversityNanning 530004China state Key Laboratory of Featured Metal Materials and Life-Cycle safety for Composite structures Guangxi UniversityNanning 530004China

Functionally graded materials(FGMs)are a novel class of composite materials that have attracted significant attention in the field of engineering due to their unique mechanical *** study aims to explore the dynamic behaviors of an FGM stepped beam with different boundary conditions based on an efficient solving *** the assumptions of the Euler-Bernoulli beam theory,the governing differential equations of an individual FGM beam are derived with Hamilton’s principle and decoupled via the separation-of-variable ***,the free and forced vibrations of the FGM stepped beam are solved with the transfer matrix method(TMM).Two models,i.e.,a three-level FGM stepped beam and a five-level FGM stepped beam,are considered,and their natural frequencies and mode shapes are *** demonstrate the validity of the method in this paper,the simulation results by ABAQUs are also *** this basis,the detailed parametric analyses on the frequencies and dynamic responses of the three-level FGM stepped beam are carried *** results show the accuracy and efficiency of the TMM.

关键词： transfer matrix method(TMM) free vibration forced vibration functionally graded material(FGM) stepped beam

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Molecular investigation into the transformation of recalcitrant dissolved organic sulfur in refinery sour water during stripping process

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Petroleum science 2024年第3期21卷 2112-2119页

作者： Yu-Guo Li Chen He Chun-Mao Chen Fan Liu quan shi state Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China state Key Laboratory of Coal Mining and Clean Utilization Beijing 100013China PetroChina Ningxia Petrochemical Company Yinchuan 750021NingxiaChina

Refinery sour water primarily originates from the tops of towers in various units and coker condensate,and cannot be discharged directly to a wastewater treatment plant due to high levels of chemical oxygen demand(COD)and organic sulfur *** after the recovery of H_(2)s from the sour water by the stripping process,the effluent still contains a high concentration of dissolved organic sulfur(DOs),which can have a huge bad *** chemical composition of dissolved organic matter(DOM)in refinery wastewater has been extensively studied,the investigation of recalcitrant DOs from sour waters remains *** the present study,chemical composition of sour water DOMs(especially DOs)was investigated using fluorescence spectroscopy(excitation-emission matrix,EEM)and mass spectrometry,including gas chromatography-mass spectrometry(GC-Ms)and high-resolution Orbitrap *** GC-Ms and EEM results showed that volatile and low-aromaticity compounds were effectively removed during the stripping process,while compounds with high hydrophilicity and humification degree were found to be more *** Orbitrap Ms results showed that weak-polar oxygenated sulfur compounds were easier to be removed than oxygenated ***,the effluent still contained significant amounts of sulfur-containing compounds with multiple sulfur atoms,particularly in the form of highly unsaturated and aromatic *** Orbitrap Ms/Ms results of CHOs-containing compounds from the effluent indicate that the sulfur atoms may exist as sulfonates,disulfide bonds,*** the composition and structure of sour water DOs is crucial for the development of effective treatment processes that can target polysulfide compounds and minimize their impact on the environment.

关键词： Molecular transformation Dissolved organic sulfur stripping process Refinery sourwater Orbitrap Ms

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Hierarchical model updating for high-speed maglev vehicle/guideway coupled system based on multiobjective optimization

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Frontiers of structural and Civil Engineering 2024年第5期18卷 788-804页

作者： Dexiang Li Jingyu huang College of Civil Engineering Tongji UniversityShanghai 200092China National Maglev Transportation Engineering R&D Center Tongji UniversityShanghai 201804China

The high-speed maglev vehicle/guideway coupled model is an essential simulation tool for investigating vehicle dynamics and mitigating coupled *** improve its accuracy efficiently,this study investigated a hierarchical model updating method integrated with field ***,a high-speed maglev vehicle/guideway coupled model,taking into account the real effect of guideway material properties and elastic restraint of bearings,was developed by integrating the finite element method,multi-body dynamics,and electromagnetic levitation ***,simultaneous in-site measurements of the vehicle/guideway were conducted on a high-speed maglev test line to analyze the system response and structural modal *** the hierarchical updating,an Elman neural network with the optimal Latin hypercube sampling method was used to substitute the FE guideway model,thus improving the computational *** multi-objective particle swarm optimization algorithm with the gray relational projection method was applied to hierarchically update the parameters of the guideway layer and magnetic force layer based on the measured modal parameters and the electromagnet vibration,***,the updated coupled model was compared with the field measurements,and the results demonstrated the model’s accuracy in simulating the actual dynamic response,validating the effectiveness of the updating method.

关键词： high-speed maglev vehicle/guideway coupled model field measurement model updating neural network multi-objective optimization

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Timing of biomarker changes preceding Alzheimer's disease:for diagnosis, treatment or prevention?

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science China Life sciences 2024年

作者： Meina quan Innovation Center for Neurological Disorders and Department of Neurology Xuanwu Hospital Capital Medical University National Medical Center for Neurological Diseases and National Clinical Research Center for Geriatric Diseases Center of Alzheimer's Disease Beijing Institute of Brain Disorders Collaborative Innovation Center for Brain Disorders

The pathophysiological and behavioural features of Alzheimer’s disease (AD) have been extensively investigated in transgenic mouse models, including the temporal sequence of each pathophysiological change and behavioural abnormality, a summary of which was recently presented by our team in this Journal (Li et al.,2023). Nevertheless, studying such features and timings directly in human patients before symptoms occur is challenging. starting from familial AD, then gradually shifting to sporadic AD, growing evidence from longitudinal studies indicates that biomarkers change at least10 to 20 years before the onset of symptoms in AD (Bateman et al., 2012;Villemagne et al., 2013; Gordon et al.,2018; Vermunt et al., 2019).

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A Multi-strategy-Improved Northern Goshawk Optimization Algorithm for Global Optimization and Engineering Design

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Computers, Materials & Continua 2024年第7期80卷 1677-1709页

作者： Liang Zeng Mai Hu Chenning Zhang quan Yuan shanshan Wang school of Electrical and Electronic Engineering Hubei University of TechnologyWuhan430068China Hubei Key Laboratory for High-Efficiency Utilization of solar Energy and Operation Control of Energy storage system Hubei University of TechnologyWuhan430068China

Optimization algorithms play a pivotal role in enhancing the performance and efficiency of systems across various scientific and engineering *** enhance the performance and alleviate the limitations of the Northern Goshawk Optimization(NGO)algorithm,particularly its tendency towards premature convergence and entrapment in local optima during function optimization processes,this study introduces an advanced Improved Northern Goshawk Optimization(INGO)*** algorithm incorporates a multifaceted enhancement strategy to boost operational ***,a tent chaotic map is employed in the initialization phase to generate a diverse initial population,providing high-quality feasible ***,after the first phase of the NGO’s iterative process,a whale fall strategy is introduced to prevent premature convergence into local *** is followed by the integration of T-distributionmutation strategies and the state Transition Algorithm(sTA)after the second phase of the NGO,achieving a balanced synergy between the algorithm’s exploitation and *** research evaluates the performance of INGO using 23 benchmark functions alongside the IEEE CEC 2017 benchmark functions,accompanied by a statistical analysis of the *** experimental outcomes demonstrate INGO’s superior achievements in function optimization ***,its applicability in solving engineering design problems was verified through simulations on Unmanned Aerial Vehicle(UAV)trajectory planning issues,establishing INGO’s capability in addressing complex optimization challenges.

关键词： Northern Goshawk Optimization tent chaotic map T-distribution disturbance state transition algorithm UAV path planning

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Revisiting the Mg isotopic systematics of siliciclastic components of sediments and sedimentary rocks:A new geochemical proxy of continental weathering in Earth's history

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science China Earth sciences 2024年第2期67卷 620-633页

作者： Tianzheng huang Bing sHEN Kangjun huang Meng NING Chao LI Jinzhuang XUE Yuanlin sUN Baoqi huang Key Laboratory of Orogenic Belt and Crustal Evolution MOESchool of Earth and Space SciencesPeking UniversityBeijing100871China state Key Laboratory of Continental Dynamics Shaanxi Key Laboratory of Early Life and EnvironmentsDepartment of GeologyNorthwest UniversityXi’an710069China Institute of sedimentary Geology Chengdu University of TechnologyChengdu610059China Key Laboratory of Rhenium-Osmium Isotopic Geochemistry Chinese Academy of Geological SciencesBeijing100037China

The Mg isotopic compositions of siliciclastic components(δ^(26)Mg_(sili))of sediments and sedimentary rocks have been commonly used to constrain the intensity of continental weathering,based on observations of,(1)an upward enrichment of26Mg in modern weathering profiles,(2)preferential uptake of26Mg in soil clays,and(3)general positive correlations between weathering intensities andδ^(26)Mg_(sili)***,not all weathering profiles display an upward increase ofδ^(26)Mg_(sili),and not all soil clays enrich in26Mg,complicating the interpretations ofδ^(26)Mg_(sili)data of sediments and sedimentary *** further explore the controls ofδ^(26)Mg_(sili)of sediments and sedimentary rocks,here we measuredδ^(26)Mg_(sili),mineralogical compositions and major element compositions of deep sea sediments from south China sea(sCs)and carbonate rock samples from two late Paleozoic sections in south *** samples show decreasing trends of both normalized Mg concentration(Mgnorm)andδ^(26)Mg_(sili)values with the increase of weathering intensity,while sCs sediments samples do not show any correlation between Mgnormorδ^(26)Mg_(sili)values and weathering intensity.A three-stages weathering model is developed to explain the observed Mgnorm andδ^(26)Mg_(sili)*** the new model,weathering can be divided into three stages,(1)the preliminary weathering stage characterized by dissolution of primary minerals and formation of secondary clay minerals in saprolite,(2)the transitional stage with massive vermiculite and chlorite formation on the bottom of soil,and(3)the advanced stage showing dissolution of vermiculite and chlorite in the top of *** new model explains anδ^(26)Mg_(sili)increase and Mgnormdecrease with an increase weathering intensity in preliminary weathering stage and decrease of Mgnormandδ^(26)Mg_(sili)with increase weathering intensity in advanced weathering *** revised weathering model warrants the application of Mg isotope in the study of contin

关键词： Clay mineral Chemical weathering CIA soil Weathering model

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