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Monitoring and evaluation of the water quality of the Lower Neches River, Texas, USA

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Water Science and Engineering 2024年第1期17卷 21-32页

作者： Qin Qian mengjie He Frank Sun Xinyu Liu Department of Civil and Environmental Engineering Lamar UniversityBeaumontTX 77710USA Department of Industry Engineering Lamar UniversityBeaumontTX 77710USA Department of Computer Science Lamar UniversityBeaumontTX 77710USA

Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic conditions.The statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to dilution.The flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the river.The correlation between E.coli and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for E.coli to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor measurements.The correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land cover.Therefore,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.

关键词： Water quality Pearson correlation analysis Lower Neches River YSI wireless sensors Non-point pollution

Terminal attitude selection method of missile attack aircraft

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Chinese Journal of Aeronautics 2024年第2期37卷 385-400页

作者： Peng HOU Yang PEI Yuxue GE mengjie ZHU School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Research Department Shanghai Electro-Mechanical Engineering InstituteShanghai 201108China

The appropriate terminal attitude of missile is important to improve the damage effectiveness of fragmentation warhead against aircraft targets.In this paper,three missile terminal attitude selection methods are proposed to solve the problem of terminal attitude selection in different situations according to their respective evaluation indexes.The MVE-based method uses the damage probability of each detonation point around the aircraft at a given attitude of missile to calculate the Mean Volume of Effectiveness(MVE)at the corresponding attitude,and then uses the MVE for different attitudes to select the terminal strike attitude.The detonation position-based method addresses the case where the missile detonation position can be assessed in advance.Given the effects of missile guidance errors and fuze activation position errors,Monte Carlo simulations are used to calculate the damage probability of aircraft with different strike attitudes,from which the terminal strike attitude is selected.The BP-ANN model-based method uses the constructed Back Propagation Artificial Neural Network(BP-ANN)model instead of simulation to calculate the evaluation indexes in the corresponding cases of MVE-based method and Detonation position-based method,which can improve the efficiency of attitude selection.Simulations are conducted for different scenarios to verify the feasibility and effectiveness of the proposed method.

关键词： Aircraft vulnerability Attitude selection BP-ANN Damage probability Damage effectiveness

HIV Infection and Associated Factors Among Out-of-School MSM Aged 16–24 Years—6 Cities and Tianjin Municipality,China,2022–2023

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China CDC weekly 2024年第3期6卷 45-50页

作者： Hui Liu Qiyu Zhu Lei Zhang Yujing Liu Peng Xu mengjie Han National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Chinese Association of STD and AIDS Prevention and Control BeijingChina Beijing Chaoyang Kangzhong Health and Education Center BeijingChina

What is already known about this topic?Approximately 80%of newly diagnosed human immunodeficiency virus(HIV)cases among individuals aged 15–24 years in China are attributed to out-ofschool youth.What is added by this report?This study presents findings on HIV prevalence and comprehensive insights into HIV service utilization,risky behaviors,and prevention knowledge among young out-of-school men who have sex with men(MSM)aged 16–24 years in China.This population exhibits a disproportionately high burden of HIV,with only 51.6%of HIV cases previously diagnosed.What are the implications for public health practice?HIV services should be expanded to include these key populations.Tailored interventions are needed to remove barriers to regular HIV services faced by young key populations.

关键词： prevention remove expanded

Biological porous carbon encapsulated polyethylene glycol-based phase change composites for integrated electromagnetic interference shielding and thermal management capabilities

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Journal of Materials Science & Technology 2022年第18期113卷 147-157页

作者： Shuang Liu mengjie sheng Hao Wu Xuetao Shi Xiang Lu Jinping Qu Key Laboratory of Material Chemistry for Energy Conversion and Storage Huazhong University of Science&TechnologyMinistry of EducationWuhan 430074PR China Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Huazhong University of Science&TechnologyWuhan 430074PR China Hubei Key Laboratory of Material Chemistry and Service Failure School of Chemistry and Chemical EngineeringHuazhong University of Science&TechnologyWuhan 430074PR China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072China School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023PR China

The development of functional composites with excellent thermal management capabilities and electro-magnetic interference(EMI)shielding has become extremely urgent for keeping up with the continuous improvement of the operating speed and efficiency for electronic equipment.In this study,the biolog-ical wood-derived porous carbon(WPC)was determined as the supporting material to encapsulating polyethylene glycol(PEG),and a series of WPC/PEG/Fe_(3)O_(4) phase change composites(PCCs)with excel-lent shape stability,EMI shielding and thermal management capabilities were prepared via a simple vac-uum impregnation method.The Fe_(3)O_(4) magnetic particles modified PCCs have greatly improved the EMI shielding effectiveness(SE).The EMI SE of WP-4(7.5 wt.% Fe_(3)O_(4) in PEG)can be up to 55.08 dB between 8.2−12.4 GHz,however,the WP-0 without Fe_(3)O_(4) addition is only 40.08 dB.Meanwhile,the absorption ratio of electromagnetic waves(EMW)has also increased from 75.02%(WP-0)to 85.56%(WP-4),which effectively prevents secondary pollution.In addition,after wrapping a thin layer of polydimethylsiloxane resin(PDMS),the obtained WP-4 can maintain a high heat storage capacity(109.52 J/g)and good wa-ter stability.In short,the prepared WPC/PEG/Fe_(3)O_(4) PCCs have great potential application value in the thermal management and electromagnetic shielding requirements for electronic devices.

关键词： Biological wood-derived porous carbon Polyethylene glycol Phase change composites Thermal management Electromagnetic interference shielding

Design and validation of a variable camber wing structure

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Chinese Journal of Aeronautics 2024年第2期37卷 1-11页

作者： Xiasheng SUN Jingfeng XUE Jin ZHOU Zhigang WANG Wenjuan WANG mengjie ZHANG Chinese Aeronautical Establishment Beijing 100012China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Aircraft Strength Research Institute of China Xi’an 710065China Graduate School of Chinese Aeronautical Establishment Yangzhou 225002China

Variable camber wing technology is one of the important development trends of green aviation at present.Through smooth,seamless,continuous and adaptive change of wing camber,the aerodynamic performance is improved in achieving increase in lift and reduction in resistance and noise.Based on the aerodynamic validation model CAE-AVM,Chinese Aeronautical Establishment(CAE)has carried out the design and validation of a variable camber wing,proposed an aerodynamic deformation matrix for the leading and trailing edges of aircraft wings in takeoff,landing and cruise conditions.Various structures and driving schemes are compared,and several key technology problems of leading and trailing edge deformation are solved.A full-size leading edge wind tunnel test piece with a span of 2.7 m and a trailing edge ground function test piece are developed.The deformation and shape maintenance capabilities of the leading edge is verified under real wind load conditions,and the load bearing and deformation capabilities of the trailing edge is verified under simulated follow-on load.The results indicate that the leading and trailing edges of the variable camber wing can achieve the required deformation angle and have a certain load-bearing capacity.Our study can provide some insights into the application of variable camber wing technology for civil aircraft.

关键词： Variable camber wing Leading edge Trailing edge Structure Measurement and control Test

Shallow sub-lakes are essential for sustaining the successful wintering of waterbirds in Poyang Lake,China

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Avian Research 2024年第2期15卷 219-228页

作者： mengjie Lu Zhen Zhang Peng Chen Changxin Xu Bin Gao Luzhang Ruan School of Life Sciences Nanchang UniversityNanchang330031China Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity Center for Watershed EcologyInstitute of Life Science and School of Life SciencesNanchang UniversityNanchang330031China

For migratory waterbirds,the quality of wintering habitat is related to spring migration and successful breeding in the next year.The availability of food resources in the habitat is critical and varies within water levels.Although the water-level fluctuations in Poyang Lake have been extremely variable interannually in recent years,the wintering waterbird populations have remained relatively stable.Hence,the mechanism of maintaining the stability is worth exploring.This study aimed to compare the distribution of vegetation and herbivorous wa-terbirds in 2015-2016 and 2016-2017,focusing on three shallow sub-lakes and one main lake are.The results showed that the emergence of tubers and the growth of Carex spp.provided a continuous food supply and habitat for wintering waterbirds with a gradual decline in the water level.Shallow sub-lakes supported almost all of the tuber-eating waterbirds(1.42-1.62×10^(5))and most geese(1.34-1.53×10^(6)).However,the main lake area,covered with Persicaria hydropiper,did not provide adequate and accessible food.This resulted in almost no distribution of tuber-eating waterbirds,with only a few geese congregating in early winter.Our results demonstrated that the shallow sub-lakes under human control provided a different environment from the main lake and are key to sustaining the successful wintering of hundreds of thousands of migratory waterbirds in Poyang Lake.Therefore,we recommend refining the anthropogenic management of the shallow sub-lakes to regulate the water level to ensure the carrying capacity of Poyang Lake.

关键词： Anthropogenic management Carrying capacity Seasonal lake Water level Wintering habitat

Repressing iron overload ameliorates central poststroke pain via the Hdac2-Kv1.2 axis in a rat model of hemorrhagic stroke

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Neural Regeneration Research 2024年第12期19卷 2708-2722页

作者： He Fang mengjie Li Jingchen Yang Shunping Ma Li Zhang Hongqi Yang Qiongyan Tang Jing Cao Weimin Yang Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Molecular Neuropathology Beijing Neurosurgical InstituteCapital Medical UniversityBeijingChina Department of Nutrition The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Neurology Henan Provincial People’s HospitalZhengzhouHenan ProvinceChina Department of Human Anatomy School of Basic Medical SciencesZhengzhou UniversityZhengzhouHenan ProvinceChina Neuroscience Research Institute Zhengzhou University Academy of Medical SciencesZhengzhouHenan ProvinceChina

Thalamic hemorrhage can lead to the development of central post-stroke pain.Changes in histone acetylation levels,which are regulated by histone deacetylases,affect the excitability of neurons surrounding the hemorrhagic area.However,the regulato ry mechanism of histone deacetylases in central post-stroke pain remains unclea r.Here,we show that iron overload leads to an increase in histone deacetylase 2expression in damaged ventral posterolateral nucleus neurons.Inhibiting this increase restored histone H3 acetylation in the Kcna2 promoter region of the voltage-dependent potassium(Kv)channel subunit gene in a rat model of central post-stroke pain,thereby increasing Kcna2expression and relieving central pain.However,in the absence of nerve injury,increasing histone deacetylase 2 expression decreased Kcna2expression,decreased Kv current,increased the excitability of neurons in the ventral posterolateral nucleus area,and led to neuropathic pain symptoms.Moreover,treatment with the iron chelator deferiprone effectively reduced iron overload in the ventral posterolateral nucleus after intracerebral hemorrhage,reversed histone deacetylase 2 upregulation and Kv1.2 downregulation,and alleviated mechanical hypersensitivity in central post-stroke pain rats.These results suggest that histone deacetylase 2 upregulation and Kv1.2 downregulation,mediated by iron overload,are important factors in central post-stroke pain pathogenesis and co uld se rve as new to rgets for central poststroke pain treatment.

关键词： central post-stroke pain hemorrhagic stroke histone deacetylase iron overload voltage-gated potassium ion channel 1.2

The ground state solutions for the Choquard equation with p-Laplacian on finite lattice graphs

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Acta Mathematica Sinica,English Series 2024年

作者： Yang LIU mengjie ZHANG School of Mathematics Renmin University of China Department of Mathematical Sciences Tsinghua University

In this paper, we study the p-Laplacian Choquard equation ■ on a finite lattice graph Nnwith n ∈ N+, where p > 1, q > 1 and 0 ≤ α ≤ n are some constants,V(x) is a positive function on Nn. Using the Nehari method, we prove that if 1 < p < q < +∞, then the above equation admits a ground state solution. Previously, the p-Laplacian Choquard equation on finite lattice graph has not been studied, and our result contains the critical cases α = 0 and α = n,which further improves the study of Choquard equations on lattice graphs.

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Multi-layer hierarchical cellulose nanofibers/carbon nanotubes/vinasse activated carbon composite materials for supercapacitors and electromagnetic interference shielding

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Nano Research 2024年第3期17卷 904-912页

作者： Tianxu Wang Chuanyin Xiong Yongkang Zhang Bo Wang Qing Xiong mengjie Zhao Yonghao Ni College of Bioresources Chemical&Materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China Department of Chemical and biomedical Engineering The University of MaineOronoME 04469USA University of New Brunswick Limerick Pulp&Paper CtrFrederictonNB E3B 5A3Canada

Developing porous self-supporting electrodes with excellent conductivity,good mechanical properties,and high electrochemical activity is crucial for constructing electrode materials with lightweight,ultra-thin,flexible,and high capacitance performance.In this work,we prepared a cellulose nanofibers(CNFs)/carbon nanotubes(CNTs)/vinasse activated carbon(VAC)(CCV)composite material with a multi-layer hierarchical conductive structure through simple vacuum filtration and freeze-drying.In this composite material,the self-assembly of CNF provides the main skeleton structure of a multi-layer hierarchical structure.CNT provides a fast path for the rapid transfer of electrons and is beneficial for the loss of electromagnetic waves.VAC provides sufficient double layer performance.The synergistic effect of the above three endows CCV composite materials with excellent energy storage performance and electromagnetic interference(EMI)shielding performance.In addition,we endowed the CCV composite with a certain shape and performance by introducing a vitrimer polymer with a dynamic cross-linked network structure.In summary,thanks to the synergistic effect of various components in the multi-layer hierarchical structure,CCV composite materials exhibit excellent integration performance,especially stable energy storage performance and EMI shielding performance.These significant properties make CCV composite materials have great application prospects in the fields of energy storage and intelligent EMI shielding.

关键词： self-supporting electrodes multi-layer hierarchical structure supercapacitors electromagnetic interference shielding