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Particuology 2024年第6期89卷 99-108页

作者： weihao l.u Huanhuan He Qingtao l.u Xin Wan Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing100191China School of Space and Environment Beihang UniversityBeijing102206China Tianmushan laboratory Hangzhou310023China

The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel *** recent years,it has been shown that heteroatoms(B,O,S,P,Cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and ***,the optimal location of the heteroatoms remains ***,taking chalcogen heteroatoms(S and Se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–C *** first coordination shell of the iron single atom is identified as the optimal doping *** optimized catalysts Fe–N_(3)Se_(1)/NC and Fe–N_(3)Se_(1)/NC demonstrate improved activity and stability in both half cells and fuel *** work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts.

关键词： Oxygen reduction reaction Fe-N-C catalysts Hetero-atom doping Doping position Enhancement mechanism

Nonlinear Filtering With Sample-Based Approximation under Constrained Communication:Progress, Insights and Trends

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1539-1556页

作者： weihao Song Zidong Wang Zhongkui li Jianan Wang Qing-long Han IEEE the State Key laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceCollege of Engineering Peking University the Department of Computer Science Brunel University London the School of Aerospace Engineering Beijing Institute of Technology the School of Science Computing and Engineering Technologies Swinburne University of Technology

The nonlinear filtering problem has enduringly been an active research topic in both academia and industry due to its ever-growing theoretical importance and practical *** main objective of nonlinear filtering is to infer the states of a nonlinear dynamical system of interest based on the available noisy measurements. In recent years, the advance of network communication technology has not only popularized the networked systems with apparent advantages in terms of installation,cost and maintenance, but also brought about a series of challenges to the design of nonlinear filtering algorithms, among which the communication constraint has been recognized as a dominating concern. In this context, a great number of investigations have been l.unched towards the networked nonlinear filtering problem with communication constraints, and many samplebased nonlinear filters have been developed to deal with the highly nonlinear and/or non-Gaussian scenarios. The aim of this paper is to provide a timely survey about the recent advances on the sample-based networked nonlinear filtering problem from the perspective of communication constraints. More specifically, we first review three important families of sample-based filtering methods known as the unscented Kalman filter, particle filter,and maximum correntropy filter. Then, the latest developments are surveyed with stress on the topics regarding incomplete/imperfect information, limited resources and cyber ***, several challenges and open problems are highlighted to shed some lights on the possible trends of future research in this realm.

关键词： Communication constraints maximum correntropy filter networked nonlinear filtering particle filter sample-based approximation unscented Kalman filter

Roles of nanoparticles in arsenic mobility and microbial community composition in arsenic-enriched soils

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Journal of Environmental Sciences 2024年第4期138卷 301-311页

作者： Ting luo Qining Zheng Jie Yu weihao liang Yan Sun Guixiang Quan Feng Zhou School of Environmental Science and Engineering Yancheng Institute of TechnologyYancheng 224051China Jiangsu Provincial Key laboratory of Coastal Ecology and Pol.ution Control Yancheng 224051China School ofEnvironment and Civil Engineering Jiangnan UniversityWuxi 214122China

Environmental effects of nano remediation engineering of arsenic(As)pol.ution need to be *** this study,the roles of Fe_(2)O_(3)and TiO_(2)nanoparticles(NPs)on the microbial mediated As mobilization from As contaminated soil were *** addition of Fe_(2)O_(3)and TiO_(2)NPs restrained As(V)release,and stimulated As(Ⅲ)***(V)concentration decreased by 94% and 93% after Fe_(2)O_(3)addition,and decreased by 89% and 45% after Ti O_(2)addition compared to the Biotic and Biotic+Acetate(amended with sodium acetate)controls,*** maximum values of As(Ⅲ)were 20.5 and 27.1μg/l at 48 d after Fe_(2)O_(3)and TiO_(2)NPs addition,respectively,and were higher than that in Biotic+Acetate control(12.9μg/l).The released As co-precipitated with Fe in soils in the presence of Fe_(2)O_(3)NPs,but adsorbed on TiO_(2)NPs in the presence of TiO_(2)***,the addition of NPs amended with sodium acetate as the electron donor clearly promoted As(V)reduction induced by *** NPs addition changed the relative abundance of soil bacterial community,while Proteobacteria(42.8%-70.4%),Planctomycetes(2.6%-14.3%),and Firmicutes(3.5%-25.4%)were the dominant microorganisms in *** potential As/Fe reducing bacteria were related to Pseudomonas,Geobacter,Desul.uromonas,and *** addition of Fe_(2)O_(3)and TiO_(2)NPs induced to the decrease of arr A *** results indicated that the addition of NPs had a negative impact on soil microbial population in a long *** findings offer a relatively comprehensive assessment of Fe_(2)O_(3)and TiO_(2)NPs effects on As mobilization and soil bacterial communities.

关键词： Fe_(2)O_(3)and TiO_(2)nanoparticles Arsenic reduction Mobilization Functional gene Microbial community

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cel.ular & Molecular Immunology 2024年第2期21卷 103-118页

作者： S.Cankat M.u.Demael l.Swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of SARS-CoV-2,MERS-CoV and the four seasonal coronaviruses(HCoV-OC43,Nl63,HKu1 and 229E)in humans and the potential for future zoonotic *** will highlight how first-generation SARS-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection universal

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： u.S.Mahabaleshwar G.P.Vanitha l.M.Pérez Emad H.Aly I.Pop Department of Studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

Noncoding RNAs：＇our turn＇ to join the p53 networ

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Journal of Molecular Cell Biology 2014年第3期8卷 179-180页

作者： Yong li Hua l.u Department of Biochemistry and Molecular Biology School of Medicine University of Louisville 319 Abraham Flexner Way Louisville KY40202 USA E-mail: yong.ti@louisviUe.edu Department of Biochemistry& Molecular Biology andTulane Cancer Center TulaneUniversity School ofMedicine New Orleans LA70112 USA

The p53 tumor suppressor is the guardian of the rrr- o human genome. Since ,ts discovery in pS3 has been the most studied molecule in the field of cancer. Recently, its role has also been extended to other biological and pathological processes, p53 functions primarily as a transcription factor to regulate target genes that encode proteins crucial for promot- ing apoptotic cell death, cell cycle arrest, senescence, and so on in response to diverse upstream stressors. Interestingly, some of the p53 targets are noncoding RNAs. Noncoding RNAs can be functional without being translated into proteins and are often independent RNA molecules or noncoding parts of messenger RNAs. The past decade has witnessed bur- geoning intensive investigation on the interplay of noncoding RNAs with p53, its regulators, and effectors during the development of cancer and/or other dis- eases. This issue of Journal of Molecular Cell Biology presents five essays to review the rapid progress in this area from five different angles and to offer new insight into the role of noncoding RNAs in the p53 signaling web with updated information.

关键词：非编码RNA BP网络分子细胞生物学 P53 编码蛋白质细胞周期阻滞 p53 人类基因组

新能源并网换流器功率控制稳定机理分析及改进控制策略

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高电压技术 2024年第8期50卷 3736-3744页

作者：叶伟豪郭强赵兵兰天楷中国电力科学研究院有限公司北京100192

在大规模新能源并网的背景下,作为并网接口的电压源型换流器得到了广泛应用。为了探究新能源并网换流器接入弱电网的功率控制稳定问题,对比分析了换流器在不同外环控制策略下自身的无功支撑能力对系统静态稳定极限的影响,基于关键电气... 详细信息

在大规模新能源并网的背景下,作为并网接口的电压源型换流器得到了广泛应用。为了探究新能源并网换流器接入弱电网的功率控制稳定问题,对比分析了换流器在不同外环控制策略下自身的无功支撑能力对系统静态稳定极限的影响,基于关键电气量之间的数学关系,探究了有功控制的失稳机理,并提出了有功出力变化对无功输出的影响指标。研究结果表明:PQ控制更能适应变化的一次能源出力场景,面对有功出力变化,具有较强的抗扰能力;而PV控制由于具有更高的静态稳定极限,更适合弱电网。此外,为应对新能源出力波动的场景,提出了一种改进控制策略,该策略具有较高的静态稳定极限和无功控制响应速度快的特性,其抗扰能力相较于PV控制得到了提高,最后通过时域仿真进行了验证。

关键词：弱电网电压源型换流器功率控制小扰动特性稳定性分析小信号模型

Childhood malaria in the Niger delta area of Nigeria:mothers/care givers'perception,definition and treatment practices

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Asian Pacific Journal of Tropical Medicine 2009年第3期2卷 52-58页

作者： Idogun E.Sylvester Airauhi l.u Department of Chemical Pathology University of Benin Teaching HospitalBenin City Department of Medical Microbiology Biology University of Benin Teaching HospitalBenin City

Objective:The objective of the study was to evaluate mothers/care givers perception of malaria,their treatment practices and the effects on the outcome of ***:Four hundred and sixty children were enrolled and their mothers/care givers *** children were screened for malaria parasitaemia and there after,blood specimens were obtained for biochemical and haematological evaluation from those children who met the criteria and tested positive to *** *** cell volume,electrolytes,urea, creatinine,plasma glucose,and serum bilirubin were ***:A total of 460 children were studied, 233(50.7%) males and 227(49.3%) *** malaria cases were 112(24.3%) and severe malaria 348(75.7%).Those who presented early 106(23.0%) and those who presented late 354(77.0%).Perception and definition of malaria as well as the treatment seeking behaviors vary significantly with the level of education of the mothers and care *** without formal education 68(51.9%) wrongly perceived that the etiology of malaria can only be diagnosed by native doctors compared to those with primary six education 61 (26.5%) and junior secondary education 10(10.1%).Only 43(9.3%) gave the correct dose of chloroquine syrup to their sick children,while 32(7.0%) gave at sub optimal ***:Wrong perception of malaria especially the complicated malaria and wrong treatment practices are major contributory factors to the high mortality and morbidity of malaria in *** is therefore a need for health education to correct the wrong ideas about the cause and treatment practices of malaria as part of malaria control programme.

关键词： Childhood malaria Mothers/Caregivers Perception and treatment practices Nigeria

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再生碳纤维铺层取向优化及复合材料性能

复合材料学报 2024年第7期41卷 3525-3535页

作者：黄海鸿孔令成刘威豪阮浩达合肥工业大学机械工程学院合肥230009 合肥学院先进制造工程学院合肥230601

回收得到的再生碳纤维(RCF)多为蓬松杂乱的短纤维束,基于湿法纤维取向技术可对其重新取向。传统纤维增强复合材料通常将纤维沿单向铺层,对开孔制件难以完全发挥纤维的增益效果,通过纤维曲线铺层可以提高复合材料的结构性能。本文通过设... 详细信息

回收得到的再生碳纤维(RCF)多为蓬松杂乱的短纤维束,基于湿法纤维取向技术可对其重新取向。传统纤维增强复合材料通常将纤维沿单向铺层,对开孔制件难以完全发挥纤维的增益效果,通过纤维曲线铺层可以提高复合材料的结构性能。本文通过设计纤维分散实验,研究了一定RCF含量与不同浓度羟乙基纤维素(HEC)的最优配置参数。利用自行搭建的纤维取向路径可调控装置,将制备的分散液铺放得到不同轨迹和形状的纤维毡,基于二维快速傅里叶变换(2D FFT)评价RCF的取向效果。通过模压成型制备RCF/环氧树脂(EP)复合材料开孔试样,分析了不同铺层路径对开孔试样承载能力的影响。结果表明:当6 mm RCF含量为6 g/l时,最优HEC浓度为14 g/l;按曲线路径制备的开孔试样有效减少开孔处的应力集中,较无序路径和水平路径开孔试样,极限载荷分别提高了69.5%、35.9%。研究拓宽了RCF/EP复合材料结构的设计自由度,为实现RCF材料的高性能再利用提供了参考。

关键词：再生碳纤维纤维取向路径规划再利用力学性能

Promotion of structural plasticity in area V2 of visual cortex prevents against object recognition memory deficits in aging and Alzheimer's disease rodents

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Neural Regeneration Research 2024年第8期19卷 1835-1841页

作者： Irene Navarro-lobato Mariam Masmudi-Martín Manuel F.lópez-Aranda Juan F.lópez-Téllez Gloria Delgado Pablo Granados-Durán Celia Gaona-Romero Marta Carretero-Rey Sinforiano Posadas María E.Quiros-Ortega Zafar u.Khan laboratory of Neurobiology Centro de Investigaciones Médico Sanitarias(CIMES)University of MalagaMalagaSpain Department of Medicine Faculty of MedicineUniversity of MalagaMalagaSpain Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas(CIBERNED) Institute of Health Carlos IIIMadridSpain the Donders Institute for Brain Cognition and Behaviour Radboud UniversityNijmegenThe Netherlands the Brain Metastasis Group National Cancer Research Centre(CNIO)MadridSpain the Department of Neurobiology University of California-Los AngelesLos AngelesCAUSA

Memory deficit,which is often associated with aging and many psychiatric,neurological,and neurodegenerative diseases,has been a challenging issue for *** till now,all potential drug candidates have failed to produce satisfa ctory ***,in the search for a solution,we found that a treatment with the gene corresponding to the RGS14414protein in visual area V2,a brain area connected with brain circuits of the ventral stream and the medial temporal lobe,which is crucial for object recognition memory(ORM),can induce enhancement of *** this study,we demonstrated that the same treatment with RGS14414in visual area V2,which is relatively unaffected in neurodegenerative diseases such as Alzheimer s disease,produced longlasting enhancement of ORM in young animals and prevent ORM deficits in rodent models of aging and Alzheimer’s ***,we found that the prevention of memory deficits was mediated through the upregulation of neuronal arbo rization and spine density,as well as an increase in brain-derived neurotrophic factor(BDNF).A knockdown of BDNF gene in RGS14414-treated aging rats and Alzheimer s disease model mice caused complete loss in the upregulation of neuronal structural plasticity and in the prevention of ORM *** findings suggest that BDNF-mediated neuronal structural plasticity in area V2 is crucial in the prevention of memory deficits in RGS14414-treated rodent models of aging and Alzheimer’s ***,our findings of RGS14414gene-mediated activation of neuronal circuits in visual area V2 have therapeutic relevance in the treatment of memory deficits.

关键词： behavioral performance brain-derived neurotrophic factor cognitive dysfunction episodic memory memory circuit activation memory deficits memory enhancement object recognition memory prevention of memory loss regulator of G protein signaling