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Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging

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Defence Technology（防务技术） 2024年第3期33卷 327-338页

作者： lin Qi yu Liu Chuanshun Gao Tao feng yue yu School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,etc.The performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration structure.This paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint model.In addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial sensors.Finally,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall system.Experimental results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios.

关键词： Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven

The impacts of gradually terminating nonpharmaceutical interventions for SARS-CoV-2:A mathematical modelling analysis

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Fundamental Research 2024年第2期4卷 401-411页

作者： Bin Wu yuetian yu Xing lin feng Medical Decision and Economic Group Department of PharmacyRen Ji HospitalSouth CampusSchool of MedicineShanghai Jiaotong UniversityShanghai 200000China Department of Critical Care Medicine Ren Ji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200001China Department of Health Policy and Management School of Public HealthPeking UniversityBeijing 100191China

With the expansion of vaccination programs,the policy of terminating nonpharmaceutical interventions for preventing the SARS-CoV-2 pandemic should become more flexible.The current study investigated the clinical and economic outcomes of intervention policies combining nonpharmaceutical interventions and vaccination programs for dealing with the SARS-CoV-2 pandemic.An agent-based transmission model was adopted that describes how a SARS-CoV-2 virus spreads in the populations of China.The model inputs were derived from the literature and expert opinion.The following intervention policies were simulated:no intervention,strict nonpharmaceutical interventions,and nonpharmaceutical interventions for workplace,community,school and home gradually terminated by combining vaccination programs for specified age groups(vaccination age in years:20-60,20-70,20-80,≥20,≥10 and whole population).Cumulative infections and deaths in one calendar year,costs and quality-adjusted life years(QALYs)were measured.When the vaccination program was taken up in at least the≥20 years age group in all populations,nonpharmaceutical interventions for workplace and community settings could be gradually terminated because the cumulative number of infections was<100 per 100,000 persons.Further ending nonpharmaceutical interventions in school and home settings could not meet the target even when the vaccination program had been taken up in all populations.When cumulative deaths were used as the endpoint,nonpharmaceutical interventions in workplace,community and school settings could be gradually terminated.Vaccine efficacy and coverage have substantial impacts.Terminating nonpharmaceutical interventions in workplace settings could produce the lowest cost when vaccination programs are taken up at least in the≥10 years age group;this method dominates most intervention strategies due to its lower costs and higher QALYs.According to our findings,nonpharmaceutical interventions might be gradually terminated in Chinese settings.

关键词： SARS-CoV-2 Nonpharmaceutical interventions Vaccination program Cumulative infections and deaths Economic outcomes

Antimicrobial resistance characteristics and phylogenetic relationships of pleuromutilin-resistant Enterococcus isolates from different environmental samples along a laying hen production chain

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Journal of Environmental Sciences 2024年第3期137卷 195-205页

作者： Cong lin yuxuan feng Xianjun Xie Haoyu Zhang Jie Wu Yixiao Zhu Jing yu Jingyi feng Wen Su Shanming Lai Anyun Zhang Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province Key Laboratory of Bio-Resource and Eco-Environment of Ministry of EducationCollege of Life SciencesSichuan UniversityChengdu 610065China

Antimicrobial resistance in the laying hen production industry has become a serious public health problem.The antimicrobial resistance and phylogenetic relationships of the common conditional pathogen Enterococcus along the laying hen production chain have not been systematically clarified.105 Enterococcus isolates were obtained from 115 environmental samples (air,dust,feces,fies,sewage,and soil) collected along the laying hen production chain (breeding chicken,chick,young chicken,and commercial laying hen).These Enterococcus isolates exhibited resistance to some clinically relevant antibiotics,such as tetracycline (92.4%),streptomycin (92.4%),and erythromycin (91.4%),and all strains had multidrug resistance phenotypes.Whole genome sequencing characterized 29 acquired antibiotic resistance genes (ARGs) that conferred resistance to 11 classes of antibiotics in 51pleuromutilin-resistant Enterococcus isolates,and lsa(E),which mediates resistance to pleuromutilins,always co-occurred with lnu(B).Alignments with the Mobile Genetic Elements database identified four transposons (Tn554,Tn558,Tn6261,and Tn6674) with several ARGs(erm(A),ant(9)-la,fex(A),and optrA) that mediated resistance to many clinically important antibiotics.Moreover,we identified two new transposons that carried ARGs in the Tn554 family designated as Tn7508 and Tn7492.A complementary approach based on conventional multi-locus sequence typing and whole genome single nucleotide polymorphism analysis showed that phylogenetically related pleuromutilin-resistant Enterococcus isolates were widely distributed in various environments on different production farms.Our results indicate that environmental contamination by antimicrobial-resistant Enterococcus requires greater attention,and they highlight the risk of pleuromutilin-resistant Enterococcus and ARGs disseminating along the laying hen production chain,thereby warranting effective disinfection.

关键词： Antimicrobial resistance Enterococcus Laying hen production chain Pleuromutilin

Impact of open hepatectomy on postoperative bile leakage in patients with biliary tract cancer

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 67-75页

作者： Gang Wu Wen-Ying Li yu-Xing Gong feng lin Chen Sun General Surgery Department The Second Affiliated Hospital of Harbin Medical UniversityHarbin 150000Heilongjiang ProvinceChina

BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer.AIM To evaluate the incidence,risk factors,and management of bile leakage after open hepatectomy in patients with biliary tract cancer.METHODS We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February 2023.Bile leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on imaging.The incidence,severity,timing,location,and treatment of the bile leaks were recorded.The risk factors for bile leakage were analyzed using univariate and multivariate logistic regression analyses.RESULTS The incidence of bile leak was 16.7%(20/120),and most cases were grade A(75%,15/20)according to the International Study Group of Liver Surgery classification.The median time of onset was 5 d(range,1-14 d),and the median duration was 7 d(range,2-28 d).The most common location of bile leakage was the cut surface of the liver(70%,14/20),followed by the anastomosis site(25%,5/20)and the cystic duct stump(5%,1/20).Most bile leaks were treated conservatively with drainage,antibiotics,and nutritional support(85%,17/20),whereas some required endoscopic retrograde cholangiopancreatography with stenting(10%,2/20)or percutaneous transhepatic cholangiography with drainage(5%,1/20).Risk factors for bile leakage include male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion.CONCLUSION Bile leakage is a frequent complication of open hepatectomy for biliary tract cancer.However,most cases are mild and can be conservatively managed.Male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion were associated with an increased risk of bile leak.

关键词： Open hepatectomy Bile leak Biliary tract cancer Risk factors Management Complication

Recent development of three-dimension printed graphene oxide and MXene-based energy storage devices

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Tungsten 2024年第1期6卷 196-211页

作者： Liang-Hao yu Xin Tao Shang-Ru feng Jin-Tao Liu lin-lin Zhang Guang-Zhen Zhao Guang Zhu Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhou 234000China Key Laboratory of Leather of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

The research for three-dimension(3D)printing carbon and carbide energy storage devices has attracted widespread exploration interests.Being designable in structure and materials,graphene oxide(GO)and MXene accompanied with a direct ink writing exhibit a promising prospect for constructing high areal and volume energy density devices.This review not only summarizes the recent advances in 3D printing energy storage devices including printing methods,ink rheological properties,and different energy storage systems,but also discusses the printing methods related to energy storage.In addition,the binder or additive free of two-dimensional carbide materials is quite important for the present electrochemical energy storage devices,which also are presented.

关键词： 3D printing Two-dimensional materials Energy storage device Ink theological MXene

Ethylene thiourea exposure induces neurobehavioral toxicity in zebrafish by disrupting axon growth and neuromuscular junctions

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Journal of Environmental Sciences 2024年第3期137卷 108-119页

作者： Jingming Wang Zhiquan yu Yongfeng Wang yuanyao Chen lin Xiao Yanjun Zong Qiyuan feng Lianqi Peng Huiping Zhang Chunyan Liu Institute of Reproductive Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Ethylene thiourea(ETU)converted from ethylene bisdithiocarbamate(EBDC)fungicides has aroused great concern because of its prevalence and harmful effects.Although ETU-induced neurotoxicity has been reported,the potential mechanisms remain unclear.This study provided insights into its neurotoxic effects at environmentally relevant concentrations in zebrafish.Our findings showed that embryonic exposure to ETU decreased the hatch rate and delayed somite development.Furthermore,ETU treatment significantly reduced the dark velocity in the locomotion assay.The upregulated tendency of the mitogen-activated protein kinases(MAPK)pathway(mknk1,atf4,mapkapk3)screened by transcriptome analysis implied motor neuron degeneration,which was validated by subsequent morphological observation,as axon length and branches were truncated in the 62.5μg/L ETU group.However,although the rescue experiment with a p38 MAPK inhibitor(SB203580)successfully ameliorated axon degeneration,it failed to reverse the locomotion behaviors.Further exploration of transcriptome data revealed the varied expression of presynaptic scaffold protein-related genes(pcloa,pclob,bsna),whose downregulation might impair the neuromuscular junction(NMJ).Therefore,we reasonably suspected that ETU-induced neurobehavioral deficits might result from the combined effects of the MAPK pathway and presynaptic proteins.Considering this,we highlighted the necessity to take precautions and early interventions for susceptible ETU-exposed populations.

关键词： Ethylene thiourea(ETU) Behavior Neuromuscular junction MAPK signaling pathway Piccolo and bassoon Danio rerio

Macroporous Directed and Interconnected Carbon Architectures Endow Amorphous Silicon Nanodots as Low‑Strain and Fast‑Charging Anode for Lithium‑Ion Batteries

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Nano-Micro Letters 2024年第5期16卷 333-351页

作者： Zhenwei Li Meisheng Han Peilun yu Junsheng lin Jie yu Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Shenzhen Engineering Lab for Supercapacitor MaterialsSchool of Material Science and EngineeringHarbin Institute of TechnologyShenzhenUniversity TownShenzhen 518055People’s Republic of China Songshan Lake Materials Laboratory Dongguan Dongguan 523808GuangdongPeople’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion batteries.Herein,we report a unique silicon-carbon composite fabricated by uniformly dis-persing amorphous Si nanodots(SiNDs)in carbon nanospheres(SiNDs/C)that are welded on the wall of the macroporous carbon framework(MPCF)by vertical graphene(VG),labeled as MPCF@VG@SiNDs/C.The high dispersity and amor-phous features of ultrasmall SiNDs(~0.7 nm),the flexible and directed electron/Li+transport channels of VG,and the MPCF impart the MPCF@VG@SiNDs/C more lithium storage sites,rapid Li+transport path,and unique low-strain property during Li+storage.Consequently,the MPCF@VG@SiNDs/C exhibits high cycle stability(1301.4 mAh g^(-1) at 1 A g^(-1) after 1000 cycles without apparent decay)and high rate capacity(910.3 mAh g^(-1),20 A g^(-1))in half cells based on industrial electrode standards.The assembled pouch full cell delivers a high energy density(1694.0 Wh L^(-1);602.8 Wh kg^(-1))and an excellent fast-charging capability(498.5 Wh kg^(-1),charging for 16.8 min at 3 C).This study opens new possibilities for preparing advanced silicon-carbon com-posite anodes for practical applications.

关键词： Amorphous Si nanodots Low-strain Fast-charging Lithium-ion batteries

Tuning Surface Molecular Design of Porous Carbon for Blue Energy Harvesting

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Research 2024年第1期2023卷 651-662页

作者： Jian yu Zhong-lin Wang Tianwei Ma Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life cycle.However,because of limited performance,existing systems do not lend themselves to practical implementation.Although it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive mixing.Here,we show that manipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the electrodes.Our findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how manipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-lin Fan feng Zhang Qian Chen Hao-Chen Song Lu-yu Zhong yue-Xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and gas.However,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal density.In this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection system.The spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response functions.Combined with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal density.This approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal density.This accuracy level is ten times higher compared to density accuracy calculated using calibration equations.Overall,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration