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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

Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel Research Center Research Institute of Highway Ministry of TransportBejing 100088China Tunnel and Underground Engineering Research Center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service performance.The aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single train.We used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track tunnel.First,the numerical method was verified by comparing the results of numerical simulation and on-site monitoring.Then,the characteristics of aerodynamic pressure were studied.Finally,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was investigated.The results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel exit.In addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel scenarios.The pressure amplitude in the two-train case is higher than that for a single train.The maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage I.The P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage I.The P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Lanthanide-based microlasers:Synthesis,structures,and biomedical applications

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Nano Research 2024年第1期17卷 97-111页

作者： qian Zhang Yawei Liu Kai Liu Hongjie Zhang Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Xiangfu Laboratory Jiaxing 314102China

The large size of lasers limits their applications in confined spaces,such as in biosensing and in vivo brain tissue imaging.In this regard,micron-sized lasers have been developed.They exhibit great potential for biological detecting,remote sensing,and depth tracking due to their small sizes,sensitive properties of their spectral fingerprints,and flexible positional modulation in the microenvironment.Lanthanide-based luminescent materials that possess long excited-state lifetime,narrow emission bandwidth,and upconversion behaviors are promising as gain mediums for novel microlasers.In addition,lanthanide-based microlasers could be generated under natural ambient conditions with pumped or continuous light sources,which significantly promotes the practical applications of microlasers.Recent progress in the design,synthesis,and biomedical applications of lanthanide-based microlasers has been outlined in this review.Lanthanide ions doped and upconverted lanthanide-based microlasers are highlighted,which exhibit advantageous structures,miniaturized dimensions,and high lasing performance.The applications of lanthanide-based microlasers are further discussed,the upconverted microlasers show great advantages for biological applications owing to their tunable excitation and emission characteristics and excellent environmental stability.Moreover,perspectives and challenges in the field of lanthanide-based microlasers are presented.

关键词： microlasers lanthanide-based luminescent materials upconversion nanoparticles biological applications

Experimental distillation of tripartite quantum steering with an optimal local filtering operation

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Photonics Research 2024年第3期12卷 552-562页

作者： qian-XI ZHANG XIAO-XU FANG HE LU School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China

Multipartite Einstein-Podolsky-Rosen(EPR)steering admits multipartite entanglement in the presence of uncharacterized verifiers,enabling practical applications in semi-device-independent protocols.Such applications generally require stronger steerability,while the unavoidable noise weakens steerability and consequently degrades the performance of quantum information processing.Here,we propose the local filtering operation that can maximally distill genuine tripartite EPR steering from N copies of three-qubit generalized Greenberger-Horne-Zeilinger states,in the context of two semi-device-independent scenarios.The optimal filtering operation is determined by the maximization of assemblage fidelity.Analytical and numerical results indicate the advantage of the proposed filtering operation when N is finite and the steerability of initial assemblages is weak.Experimentally,a proof-of-principle demonstration of two-copy distillation is realized with the optical system.The advantage of the optimal local filtering operation is confirmed by the distilled assemblage in terms of higher assemblage fidelity with perfectly genuine tripartite steerable assemblages,as well as the greater violation of the inequality to witness genuine tripartite steerable assemblages.Our results benefit the distillation of multipartite EPR steering in practice,where the number of copies of initial assemblages is generally finite.

关键词： filtering distillation optimal

A Privacy-preserving Energy Management System Based on Homomorphic Cryptosystem for IoT-enabled Active Distribution Network

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 167-178页

作者： qian Hu Siqi Bu Wencong Su Vladimir Terzija the Department of Physics Hong Kong Baptist UniversityHong KongChina the Department of Electrical and Electronic Engineering Shenzhen Research InstituteThe Hong Kong Polytechnic UniversityHong KongChina the Department of Electrical and Computer Engineering University of Michigan-DearbornDearbornMI 48128USA the School of Engineering Newcastle UniversityNewcastleUK

Active distribution network(ADN),as a typically cyber-physical system,develops with the evolution of Internet of Things(IoTs),which makes the network vulnerable to cybersecurity threats.In this paper,the eavesdropping attacks that lead to privacy breaches are addressed for the IoT-enabled ADN.A privacy-preserving energy management system(EMS)is proposed and empowered by secure data exchange protocols based on the homomorphic cryptosystem.During the information transmission among distributed generators and load customers in the EMS,private information including power usage and electricity bidding price can be effectively protected against eavesdropping attacks.The correctness of the final solutions,e.g.,optimal market clearing price and unified power utilization ratio,can be deterministically guaranteed.The simulation results demonstrate the effectiveness and the computational efficiency of the proposed homomorphically encrypted EMS.

关键词： Eavesdropping attack energy management system homomorphic cryptosystem Internet of Things(IOTs) active distribution network(ADN) privacy-preserving

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： qian Ma Peng Jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is studied.First,an augmented system is constructed by the tracking error system and reference system.This transformation aims to convert the tracking control prob-lem into a stabilization control problem.Then,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty items.Based on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is developed.Finally,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal controller.The proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety constraints.The performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

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Mitochondrial transplantation confers protection against the effects of ischemic stroke by repressing microglial pyroptosis and promoting neurogenesis

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Neural Regeneration Research 2024年第6期19卷 1325-1335页

作者： Li Sun Zhaoyan Zhao Jing Guo Yuan Qin qian Yu Xiaolong Shi Fei Guo Haiqin Zhang Xude Sun Changjun Gao qian Yang Department of Experimental Surgery The Second Affiliated Hospital of Air Force Medical University Department of Anesthesiology The Second Affiliated Hospital of Air Force Medical University

Transferring healthy and functional mitochondria to the lateral ventricles confers neuroprotection in a rat model of ischemia-reperfusion injury. Autologous mitochondrial transplantation is also beneficial in pediatric patients with cardiac ischemia-reperfusion injury. Thus, transplantation of functional exogenous mitochondria may be a promising therapeutic approach for ischemic disease. To explore the neuroprotective effect of mitochondria transplantation and determine the underlying mechanism in ischemic stroke, in this study we established a photo-thrombosis-induced mouse model of focal ischemia and administered freshly isolated mitochondria via the tail vein or to the injury site(in situ). Animal behavior tests, immunofluorescence staining, 2,3,5-triphenyltetrazolium chloride(TTC) staining, mRNA-seq, and western blotting were used to assess mouse anxiety and memory, cortical infarct area, pyroptosis, and neurogenesis, respectively. Using bioinformatics analysis, western blotting, co-immunoprecipitation, and mass spectroscopy, we identified S100 calcium binding protein A9(S100A9) as a potential regulator of mitochondrial function and determined its possible interacting proteins. Interactions between exogenous and endogenous mitochondria, as well as the effect of exogenous mitochondria on recipient microglia, were assessed in vitro. Our data showed that:(1) mitochondrial transplantation markedly reduced mortality and improved emotional and cognitive function, as well as reducing infarct area, inhibiting pyroptosis, and promoting cortical neurogenesis;(2) microglial expression of S100A9 was markedly increased by ischemic injury and regulated mitochondrial function;(3) in vitro, exogenous mitochondria enhanced mitochondrial function, reduced redox stress, and regulated microglial polarization and pyroptosis by fusing with endogenous mitochondria; and(4) S100A9 promoted internalization of exogenous mitochondria by the microglia, thereby amplifying their pro-proliferation and anti-inflammatory effects. Taken togeth

关键词： ischemic stroke microglia mitochondria transplantation neurogenesis pyroptosis

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价值、分类与治理:一种自下而上的治理观念

理论与改革 2024年第3期 96-106,159,160页

作者：张乾友南京大学政府管理学院

治理是一个自上而下的过程,也包含自下而上的根源。从自下而上的视角出发,每一个人都是一个价值主体,希望通过自己的价值创造行为来寻找自己在社会中的位置。在这个过程中,他们发现,自己的社会位置只能通过社会的分类体系而得到定位,于... 详细信息

治理是一个自上而下的过程,也包含自下而上的根源。从自下而上的视角出发,每一个人都是一个价值主体,希望通过自己的价值创造行为来寻找自己在社会中的位置。在这个过程中,他们发现,自己的社会位置只能通过社会的分类体系而得到定位,于是,个体性的价值创造行为就转化成了群体性的分类斗争。分类斗争是社会中自发的秩序建构行为,它需要得到国家的确认,而治理的过程就表现为国家通过对分类体系的制度调整来回应作为价值主体的人们所发起的分类斗争的过程,其结果则是将作为价值主体的人们变成了分类权力的客体。这样一种关于治理的理解让我们既得以正视人作为价值主体的存在,又得以发现作为价值主体的人变成权力客体的不可避免性。

关键词：价值主体权力客体分类权力分类斗争治理

Rice AGL1 determines grain size and sterile lemma identity

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The Crop Journal 2024年第2期12卷 630-634页

作者： Haiping Yu An Wang Guangheng Zhang Guojun Dong Longbiao Guo qian qian Deyong Ren State Key Laboratory of Rice Biology and Breeding China National Rice Research InstituteHangzhou 310006ZhejiangChina Hainan Yazhou Bay Seed Laboratory Sanya 572024HainanChina National Nanfan Research Institute(Sanya) Chinese Academy of Agricultural SciencesSanya 572024HainanChina

The grass spikelet is a unique inflorescence structure that determines grain size.Although many genetic factors have been well characterized for grain size and glume development,the underlying molecular mechanisms in rice are far from established.Here,we isolated rice gene,AGL1 that controlled grain size and determines the fate of the sterile lemma.Loss of function of AGL1 produced larger grains and reduced the size of the sterile lemma.Larger grains in the agl1 mutant were caused by a larger number of cells that were longer and wider than in the wild type.The sterile lemma in the mutant spikelet was converted to a rudimentary glume-like organ.Our findings showed that the AGL1(also named LAX1)protein positively regulated G1 expression,and negatively regulated NSG1 expression,thereby affecting the fate of the sterile lemma.Taken together,our results revealed that AGL1 played a key role in negative regulation of grain size by controlling cell proliferation and expansion,and supported the opinion that rudimentary glume and sterile lemma in rice are homologous organs.

关键词： Abnormal grain and sterile lemma 1 Oryza sativa Grain size Rudimentary glume