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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 ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** 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 *** 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 *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,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

Sources appointment and health risks of PM_(2.5)-bound trace elements in a coastal city of southeastern China

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Journal of Environmental Sciences 2024年第4期138卷 561-571页

作者： Ziyi Lin Xiaolong fan Gaojie chen Youwei Hong Mengren Li Lingling Xu Baoye Hu chen Yang Yanting chen Zhiqian Shao Jinsheng chen Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy ofSciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Minnan Normal University Zhangzhou 363000China

To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Sn,Ba,Pb)in PM_(2.5)were monitored from December 2020 to November 2021 in a representative city,*** concentrations of trace elements in Xiamen displayed an obvious seasonal variation and were dominated by K,Fe,Al,Ca and *** on Positive Matrix Factorization analysis,source appointment revealed that the major sources of trace elements in Xiamen were traffic,dust,biomass and firework combustion,industrial manufacture and shipping *** to health risk assessment combined with the source appointment results,it indicated that the average noncarcinogenic risk was below the threshold and cancer risk of four hazardous metals(Cr,Ni,As,Pb)exceeded the threshold(10^(-6)).Traffic-related source had almost half amount of contribution to the health risk induced by PM_(2.5)-bound trace *** the dust transport period or Spring Festival period,the health risks exceeded an acceptable threshold even an order of magnitude higher,suggesting that the serious health risks still existed in low PM_(2.5)environment at certain *** risk assessment reminded that the health risk reduction in PM_(2.5)at southeastern China should prioritize traffic-related hazardous trace elements and highlighted the importance of controlling vehicles emissions in the future.

关键词： PM_(2.5)-bound trace elements Seasonal variations Source appointment Health risks Traffic-related source

Host cyclophilin A facilitates SARS-CoV-2 infection by binding and stabilizing spike on virions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 36-39页

作者： Xiangpeng Sheng fang Zhu Hong Peng fan Yang yi Yang Cong Yang Zhen Wang Wei chen Deyin Guo Ronggui Hu State Key Laboratory of Molecular Biology Center for Excellence in Molecular Cell ScienceShanghai Institute of Biochemistry and Cell BiologyUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghaiChina MOE Key Laboratory of Tropical Disease Control Centre for Infection and Immunity StudySchool of MedicineSun Yat-sen UniversityShenzhenChina ICU Longhua Hospital Shanghai University of Traditional Chinese MedicineShanghaiChina

Dear Editor,The novel coronavirus SARS-CoV-2 rapidly evolutes to increase its infectivity and transmissibility,facilitates its immune escape,impairs vaccine efficacy,and currently causes repeated infections in human,which is mainly determined by the accumulated mutations in spike(S).1 Transmembrane S is a heavily glycosylated protein on the surface of the virion as homotrimer,responsible for binding to human angiotensin-converting enzyme 2(hACE2)receptor.2 While the architecture of S trimers has been well studied,how the stability of S is regulated by potential host factors remains unknown.

关键词： ACE2 vaccine infection

Characteristics and Risk Factors for Pediatric Sepsis

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Current Medical Science 2024年第3期44卷 648-656页

作者： Yong-bing ZHU Tong-lin LIU Qi DAI Shu-fan LIU Peng XIONG Hao HUANG yi YUAN Tian-nan ZHANG Yu chen Department of Pediatric Intensive Care Unit Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective Sepsis is considered a major cause of health loss in children and had high mortality and ***,there is no reliable model for predicting the prognosis of pediatric patients with *** study aimed to analyze the clinical characteristics of sepsis in children and assess the risk factors associated with poor prognosis in pediatric sepsis patients to identify timely interventions and improve their *** This study analyzed the clinical indicators and laboratory results of septic patients hospitalized in the Pediatric Intensive Care Unit of Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology,China,from January 1,2019,to December 31,*** factors for sepsis were identified by logistic regression *** A total of 355 children with sepsis were enrolled,with 333 children(93.8%)in the good prognosis group,and 22 children(6.2%)in the poor prognosis *** them,there were 255 patients(71.8%)in the sepsis group,and 100 patients(28.2%)in the severe sepsis *** length of hospital stay in the poor prognosis group was longer than that in the good prognosis group(P0.05),and the platelet(PLT),albumin(ALB),and hemoglobin(Hb)levels were lower in the poor prognosis group(P<0.01).The IL-8 levels in the severe sepsis group were higher than those in the sepsis group(P<0.05).Multiple logistic regression analysis suggested that lower Hb levels,ALB levels,peak PLT counts,and higher IL-1βlevels were independent risk factors for poor prognosis in children with *** Lower Hb,ALB,and PLT counts and elevated IL-1βare independent risk factors for poor prognosis in children with sepsis.

关键词： pediatric sepsis inflammation severity prognosis risk factors

A symmetric substructuring method for analyzing the natural frequencies of conical origami structures

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 203-210页

作者： chenhao Lu Yao chen Weiying fan Jian Feng Pooya Sareh Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education and National Prestress Engineering Research CenterSoutheast UniversityNanjing 211189China School of Engineering University of LiverpoolLiverpool L693BXUnited Kingdom Creative Design Engineering Lab(Cdel) School of EngineeringNewcastle UniversityNewcastle upon Tyne NE17RUUnited Kingdom Escuela Técnica Superior de Ingeniería y Diseño Industrial Universidad Politécnica de Madrid(UPM)Madrid 28012Spain

Conical origami structures are characterized by their substantial out-of-plane stiffness and *** investigations have commonly focused on the static characteristics of these lightweight ***,the efficient analysis of the natural vibrations of these structures is pivotal for designing conicalorigami structures with programmable stiffness and *** this paper,we propose a novel method to analyzethe natural vibrations of such structures by combining a symmetric substructuring method(SSM)and a gener-alized eigenvalue *** exploits the inherent symmetry of the structure to decompose it into a finiteset of repetitive *** doing so,we reduce the dimensions of matrices and improve computationalefficiency by adopting the stiffness and mass matrices of the substructures in the generalized eigenvalue *** element simulations of pin-jointed models are used to validate the computational results of the ***,the parametric analysis of the structures demonstrates the influences of the number of seg-ments along the circumference and the radius of the cone on the structural mass and natural frequencies of ***,we present a comparison between six-fold and four-fold conical origami structures anddiscuss the influence of various geometric parameters on their natural *** study provides a strategyfor efficiently analyzing the natural vibration of symmetric origami structures and has the potential to contributeto the efficient design and customization of origami metastructures with programmable stiffness.

关键词： Natural structural vibration Origami design Group theory Symmetric substructuring method(SSM) Generalized eigenvalue analysis

Personal Thermal Management by Radiative Cooling and Heating

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Nano-Micro Letters 2024年第8期16卷 225-267页

作者： Shidong Xue Guanghan Huang Qing chen Xungai Wang Jintu fan Dahua Shou School of Fashion and Textiles The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China Future Intelligent Wear Centre The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China Shanghai International Fashion Innovation Center Donghua UniversityShanghai 200051People’s Republic of China Research Centre of Textiles for Future Fashion The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China

Maintaining thermal comfort within the human body is crucial for optimal health and overall *** merely broadening the setpoint of indoor temperatures,we could significantly slash energy usage in building heating,ventilation,and air-conditioning *** recent years,there has been a surge in advancements in personal thermal management(PTM),aiming to regulate heat and moisture transfer within our immediate surroundings,clothing,and *** advent of PTM is driven by the rapid development in nano/micro-materials and energy science and *** emerging research area in PTM is personal radiative thermal management(PRTM),which demonstrates immense potential with its high radiative heat transfer efficiency and ease of ***,it is less taken into account in traditional textiles,and there currently lies a gap in our knowledge and understanding of *** this review,we aim to present a thorough analysis of advanced textile materials and technologies for ***,we will introduce and discuss the underlying radiation heat transfer mechanisms,fabrication methods of textiles,and various indoor/outdoor applications in light of their different regulation functionalities,including radiative cooling,radiative heating,and dual-mode ***,we will shine a light on the current hurdles,propose potential strategies,and delve into future technology trends for PRTM with an emphasis on functionalities and applications.

关键词： Personal thermal management Radiative cooling and heating Thermal comfort Dynamic thermoregulation

Detachable string magnetically controlled capsule endoscopy for the noninvasive diagnosis of esophageal diseases:A prospective,blind clinical study

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World Journal of Gastroenterology 2024年第9期30卷 1121-1131页

作者： Yan-Ling Yang Huang-Wen Qin Zhao-Yu chen Hui-Ning fan yi Yu Wei Da Jin-Shui Zhu Jing Zhang Department of Gastroenterology Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China

BACKGROUND Traditional esophagogastroduodenoscopy(EGD),an invasive examination method,can cause discomfort and pain in *** contrast,magnetically controlled capsule endoscopy(MCE),a noninvasive method,is being applied for the detection of stomach and small intestinal diseases,but its application in treating esophageal diseases is not *** To evaluate the safety and efficacy of detachable string MCE(ds-MCE)for the diagnosis of esophageal *** Fifty patients who had been diagnosed with esophageal diseases were pros-pectively recruited for this clinical study and underwent ds-MCE and conven-tional *** primary endpoints included the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for patients with esophageal *** secondary endpoints consisted of visualizing the esophageal and dentate lines,as well as the subjects'tolerance of the *** Using EGD as the gold standard,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for esophageal disease detection were 85.71%,86.21%,81.82%,89.29%,and 86%,***-MCE was more comfortable and convenient than EGD was,with 80%of patients feeling that ds-MCE examination was very comfortable or comfortable and 50%of patients believing that detachable string v examination was very *** This study revealed that ds-MCE has the same diagnostic effects as traditional EGD for esophageal diseases and is more comfortable and convenient than EGD,providing a novel noninvasive method for treating esophageal diseases.

关键词： Clinical trial Detachable string magnetically controlled capsule endoscopy Esophagogastroduodenoscopy Noninvasive diagnosis Esophageal diseases

Layered metastructure containing freely-designed local resonators for wave attenuation

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Defence Technology（防务技术） 2024年第2期32卷 23-31页

作者： Yu Li Huguang He Jiang Feng Hailong chen Fengnian Jin Hualin fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007China Rocket Force University of Engineering Xi'an 710025China Henan International Joint Laboratory of Dynamics of Impact and Disaster of Engineering Structures Department of Civil EngineeringNanyang Institute of TechnologyNanyang 473004China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety and Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China

Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical *** metastructure is composed of periodic rubber layers and concrete layers embedded with three-dimensional resonators,which can be freely designed with multi local resonant frequencies to attenuate vibrations at required frequencies and widen the attenuation *** metastructure can also effectively attenuate seismic *** with layered rubber-based structures,the metastructure has more excellent wave attenuation effects with greater attenuation and wider bandgap.

关键词： Layered metastructure Local resonator Wave attenuation

Revolutionary entrapment model of uniformly distributed swarm robots in morphogenetic formation

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Defence Technology（防务技术） 2024年第1期31卷 496-509页

作者： chen Wang Zhaohui Shi Minqiang Gu Weicheng Luo Xiaomin Zhu Zhun fan Shantou University ShantouGuangdongChina National University of Defense Technology ChangshaChina Key Lab of Digital Signal and Image Processing of Guangdong Province China

This study proposes a method for uniformly revolving swarm robots to entrap multiple targets,which is based on a gene regulatory network,an adaptive decision mechanism,and an improved *** the gene regulatory network method,the robots can generate entrapping patterns according to the environmental input,including the positions of the targets and ***,an adaptive decision mechanism is proposed,allowing each robot to choose the most well-adapted capture point on the pattern,based on its *** robots employ an improved Vicsek-model to maneuver to the planned capture point smoothly,without colliding with other robots or *** proposed decision mechanism,combined with the improved Vicsek-model,can form a uniform entrapment shape and create a revolving effect around targets while entrapping *** study also enables swarm robots,with an adaptive pattern formation,to entrap multiple targets in complex *** robots can be deployed in the military field of unmanned aerial vehicles’(UAVs)entrapping multiple *** experiments demonstrate the feasibility and superiority of the proposed gene regulatory network method.

关键词： Swarm intelligence Revolutionary entrapment Flocking Robots Gene regulatory network Vicsek-model Entrapping multiple targets