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airborne transmission during short-term events: Direct route over indirect route

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Building Simulation 2022年第12期15卷 2097-2110页

作者： Xiujie li Zhengtao ai Jinjun Ye Cheuk ming Mak Hai ming Wong Department of Building Environment and Energy Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Civil Engineering Hunan UniversityChangshaChina National Center for International Research Collaboration in Building Safety and Environment Hunan UniversityChangshaChina Faculty of Dentistry The University of Hong KongHong KongChina

Numerous short-term exposure events in public spaces were reported during the COVID-19 pandemic,especially during the spread of Delta and Omicron.However,the currently used exposure risk assessment models and mitigation measures are mostly based on the assumption of steady-state and complete-mixing conditions.The present study investigates the dynamics of airborne transmission in short-term events when a steady state is not reached before the end of the events.Large-eddy simulation(LES)is performed to predict the airborne transmission in short-term events,and three representative physical distances between two occupants are examined.Both time-averaged and phase-averaged exposure indices are used to evaluate the exposure risk.The results present that the exposure index in the short-term events constantly varies over time,especially within the first 1/ACH(air changes per hour)hour of exposure between occupants in close proximity,posing high uncertainty to the spatial and temporal evolutions of the risk of cross-infection.The decoupling analysis of the direct and indirect airborne transmission routes indicates that the direct airborne transmission is the predominated route in short-term events.It suggests also that the general dilution ventilation has a relatively limited efficiency in mitigating the risk of direct airborne transmission,but determines largely the occurrence time of the indirect one.Given the randomness,discreteness,localization,and high-risk characteristics of direct airborne transmission,a localized method that has a direct interference on the respiratory flows would be better than dilution ventilation for short-term events,in terms of both efficiency and cost.

关键词： airborne transmission short-term events direct exposure transient computational fluid dynamics(CFD) exposure risk

Pathogenesis of chronic enteropathy associated with the SLCO2A1 gene:Hypotheses and conundrums

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World Journal of Gastroenterology 2024年第19期30卷 2505-2511页

作者： Zhi-Xin Xie Yue li ai-ming Yang Dong Wu Qiang Wang State Key Laboratory of Complex Severe and Rare Diseases Department of GastroenterologyPeking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Department of Clinical Medicine Peking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100730China

Chronic enteropathy associated with the SLCO2A1 gene(CEAS)is a complex gastroenterological condition characterized by multiple ulcers in the small intestine with chronic bleeding and protein loss.This review explores the potential mechanisms underlying the pathogenesis of CEAS,focusing on the role of SLCO2A1-encoded prostaglandin transporter OATP2A1 and its impact on prostaglandin E2(PGE2)levels.Studies have suggested that elevated PGE2 levels contribute to mucosal damage,inflammation,and disruption of the intestinal barrier.The effects of PGE2 on macrophage activation and Maxi-Cl channel functionality,as well as its interaction with nonsteroidal anti-inflammatory drugs play crucial roles in the progression of CEAS.Understanding the balance between its protective and pro-inflammatory effects and the complex interactions within the gastrointestinal tract can shed light on potential therapeutic targets for CEAS and guide the development of novel,targeted therapies.

关键词： SLCO2A1 Prostaglandin E2 Chronic enteropathy associated with the SLCO2A1 gene Small intestine Macrophage

Mechanism of Qili Qiangxin Capsule for Heart Failure Based on miR133a-Endoplasmic Reticulum Stress

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Chinese Journal of Integrative Medicine 2024年第5期30卷 398-407页

作者： JI Xiao-di YANG Ding CUI Xi-yuan LOU li-xia NIE Bo ZHAO Jiu-li ZHAO ming-jing WU ai-ming Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine Key Laboratory of Chinese Internal Medicine of Ministry of Education and BeijingBeijing 100700China Department of Traditional Chinese Medicine Fuwai HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100037China

Objective:To investigate the pharmacological mechanism of Qili Qiangxin Capsule(QLQX)improvement of heart failure(HF)based on miR133a-endoplasmic reticulum stress(ERS)pathway.Methods:A left coronary artery ligation-induced HF after myocardial infarction model was used in this study.Rats were randomly assigned to the sham group,the model group,the QLQX group[0.32 g/(kg·d)],and the captopril group[2.25 mg/(kg·d)],15 rats per group,followed by 4 weeks of medication.Cardiac function such as left ventricular ejection fraction(EF),fractional shortening(FS),left ventricular systolic pressure(LVSP),left ventricular end diastolic pressure(LVEDP),the maximal rate of increase of left ventricular pressure(+dp/dt max),and the maximal rate of decrease of left ventricular pressure(–dp/dt max)were monitored by echocardiography and hemodynamics.Hematoxylin and eosin(HE)and Masson stainings were used to visualize pathological changes in myocardial tissue.The m RNA expression of mi R133a,glucose-regulated protein78(GRP78),inositol-requiring enzyme 1(IRE1),activating transcription factor 6(ATF6),X-box binding protein1(XBP1),C/EBP homologous protein(CHOP)and Caspase 12 were detected by RT-PCR.The protein expression of GRP78,p-IRE1/IRE1ratio,cleaved-ATF6,XBP1-s(the spliced form of XBP1),CHOP and Caspase 12 were detected by Western blot.Td T-mediated d UTP nick-end labeling(TUNEL)staining was used to detect the rate of apoptosis.Results:QLQX significantly improved cardiac function as evidenced by increased EF,FS,LVSP,+dp/dt max,-dp/dt max,and decreased LVEDP(Paining showed that QLQX ameliorated cardiac pathologic damage to some extent.Masson staining indicated that QLQX significantly reduced collagen volume fraction in myocardial tissue(P<0.01).Results from RT-PCR and Western blot showed that QLQX significantly increased the expression of mi R133a and inhibited the m RNA expressions of GRP78,IRE1,ATF6 and XBP1,as well as decreased the protein expressions of GRP78,cleaved-ATF6 and XBP1-s and decreased p-IRE1/IRE1 rati

关键词： heart failure Qili Qiangxin Capsule miR133a endoplasmic reticulum stress apoptosis

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU li DING Shi-feng WANG ai-ming Cai Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

基于浅层视觉几何组网络的参数迁移学习及其在运动想象分类中的应用

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生物医学工程学杂志 2022年第1期39卷 28-38页

作者：许冬芹李明爱北京工业大学信息学部北京100124 北京市计算机智能和智能系统重点实验室北京100124 教育部数字社区工程研究中心北京100124

迁移学习在基于运动想象脑电信号(MI-EEG)的脑机接口(BCI)康复系统中具有潜在的研究价值和应用前景,而源域分类模型及迁移策略是直接影响目标域模型性能与迁移效率的两个重要方面。为此,本文提出一种基于浅层视觉几何组网络(sVGG)的参... 详细信息

迁移学习在基于运动想象脑电信号(MI-EEG)的脑机接口(BCI)康复系统中具有潜在的研究价值和应用前景,而源域分类模型及迁移策略是直接影响目标域模型性能与迁移效率的两个重要方面。为此,本文提出一种基于浅层视觉几何组网络(sVGG)的参数迁移学习(PTL)方法(PTL-sVGG)。首先,基于皮尔逊相关系数法对源域受试者进行筛选,并对优选的受试者MI-EEG数据进行短时傅里叶变换,获得时频谱图(TFSI);然后,对视觉几何组网络-16(VGG-16)进行结构简化与模块化设计,并利用源域TFSI完成改进的sVGG模型预训练;进而,设计基于模块的冻结—微调迁移策略,快速寻找并冻结sVGG模型中贡献最大的某个模块,再基于目标受试者TFSI微调其余模块,获得目标域分类模型。基于公开脑电信号(EEG)数据库进行实验研究,PTL-sVGG取得的平均识别率和卡帕(Kappa)值分别为94.9%和0.898。结果表明,源域受试者优选有利于改善源域模型性能,基于模块的迁移策略有效提升了迁移效率,实现了基于不同导联数的数据库跨受试者间模型参数的快速有效迁移。这将有利于减少BCI系统的校准时间,促进BCI技术在康复工程中的应用。

关键词：运动想象参数迁移学习视觉几何组网络皮尔逊相关系数迁移策略

Quorum sensing inhibition of hordenine analogs on Pseudomonas aeruginosa and Serratia marcescens

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Synthetic and Systems Biotechnology 2021年第4期6卷 360-368页

作者： Yue liu Jun-Jian li Hong-Yuan li Shi-ming Deng ai-Qun Jia School of Pharmaceutical Sciences Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island ResourcesHainan UniversityHaikou570228China

Quorum sensing(QS)plays an essential role in virulence factor production,biofilm formation,and antimicrobial resistance.As a potent QS inhibitor,hordenine can inhibit both QS and biofilm formation in Pseudomonas aeruginosa and Serratia marcescens.In this work,we tested the QS inhibitory potential of 27 hordenine analogs against QS and biofilm formation in P.aeruginosa and S.marcescens.Among the tested analogs,seven(12,28,27,26,2,23,and 7)exhibited strong QS inhibitory activity against P.aeruginosa,five of which(12,28,27,26,and 2)showed better inhibitory activity than hordenine.In addition,seven analogs(28,12,23,7,26,2,and 27)exhibited better biofilm inhibition against P.aeruginosa than hordenine.Four analogs(7,28,2,and 12)showed QS inhibitory activity against S.marcescens,two of which(7 and 28)demonstrated better inhibitory activity than hordenine.Furthermore,analog 7 showed similar biofilm inhibition against S.marcescens as hordenine.Structure-activity relationship(SAR)analysis indicated that the inhibitory activities of the analogs were related to four factors,i.e.,carbon chain length,presence or absence of anα,β-C=C bond,amino group with/without lipophilic group,such as methyl group,and hydroxyl group in benzene ring.

关键词： Hordenine analogs Pseudomonas aeruginosa Serratia marcescens Quorum sensing inhibition QSAR Biofilm

Intra-arterial tenecteplase during thrombectomy for acute stroke(BRETIS-TNK II):rationale and design

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Stroke & Vascular Neurology 2024年第1期9卷 59-65页

作者： Zi-ai Zhao Jing Qiu Wei li Thanh Nguyen Shouchun Wang Huaizhang Shi ming Wei Feng Wang Di li Hui-Sheng Chen Department of Neurology General Hospital of Northern Theater CommandShenyangLiaoning ProvinceChina Neurology RadiologyBoston Medical CenterBostonMassachusettsUSA Department of Neurology First Affiliated Hospital of Jilin UniversityChangchunJilinChina Department of Neurosurgery First Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiangChina Department of Neurosurgery Tianjin Huanhu HospitalTianjinTianjinChina Department of Interventional Therapy First Affiliated Hospital of Dalian Medical UniversityDalianChina Neurological Intervention Department Dalian Municipal Central HospitalDalianLiaoningChina

Background Our recent pilot study suggests intra-arterial tenecteplase(TNK)during the first pass of endovascular treatment(EVT)seems safe,may increase first-pass reperfusion and good outcome in acute ischaemic stroke(aiS)patients with large-vessel occlusion(LVO).aims To determine the efficacy and safety of intra-arterial TNK administration during EVT in aiS-LVO patients presenting up to 24 hours from symptom onset.Sample size estimates A maximum of 380 patients are required to test the superiority hypothesis with 80%power according to a two-side 0.05 level of significance,stratified by age,gender,baseline systolic blood pressure,prestroke modified Rankin Scale(mRS),baseline National Institute of Health stroke scale,baseline ASPECTS,time from onset to groin puncture,intravenous thrombolysis before EVT,stroke territory and stroke aetiology.Design Intra-arterial TNK during thrombectomy for acute stroke(BRETIS-TNK II)study is a prospective,randomised,adaptive enrichment,open-label,blinded end point,multicentre study.Eligible aiS-LVO patients are randomly assigned into the experimental group and control group with a ratio of 1:1.The experimental group will be treated with intra-arterial infusion of TNK during EVT.The control group will be treated with standard EVT.Outcome The primary end point is a favourable outcome,defined as an mRS score of 0–2 at 90 days.The primary safety end point is symptomatic intracranial haemorrhage within 48 hours,which is defined as an increase in the National Institutes of Health Stroke Scale score of≥4 points as a result of the intracranial haemorrhage.Conclusions The results of BRETIS-TNK II will provide evidence for the efficacy and safety of intra-arterial TNK administration during EVT in aiS patients with LVO.

关键词： rational stratified TNK

Establishment of a PCR Method for the Identification of Mink-Derived Components in Common Edible Meats

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Journal of Analysis and Testing 2022年第1期6卷 51-57页

作者： Jia-Mu Niu lin Cui Jin-Xia ai Guang-Xin Yuan li-Yuan Sun li-Jun Gao ming-Cheng li Department of Science and Technology Beihua UniversityJilin 132013China School of Technology Medicine Beihua UniversityJilin 132013China College of Pharmacy Beihua UniversityJilin 132013China

In this study,we established a DNA extraction method of meats and a PCR method for the detection of mink-derived compo-nents in common edible meats.The DNA of meats was extracted by a developed mink-derived component detection method and salting-out method,the specific primers of Cyt-b were designed,and the mink-derived components in common edible meats were identified by PCR.The results showed that the concentration and purity of mink meat DNA extracted by the two methods could meet the requirements of PCR.The mink meat DNA extracted by the developed mink DNA detection method had a high purity and yield.The mink-derived DNA in common edible meats could be identified.The specificity of mink meat DNA primer was proved to be good by repeated tests.The developed mink DNA detection method has the advantages of rapid detection and simple operation,which can be used for the identification of meat products in market and provide an experimental basis for the quality control of meat products.

关键词： Mink Cyt-b Molecular biology Identification of authenticity

基于连续小波变换和符号传递熵的脑功能网络构建方法

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电子学报 2022年第7期50卷 1600-1608页

作者：李明爱张圆圆北京工业大学信息学部北京100124 计算智能与智能系统北京市重点实验室北京100124 教育部数字社区工程研究中心北京100124

为有效利用运动想象脑电信号(Motor Imagery Electroencephalogram,MI-EEG)的频域信息并精确反映脑电极之间的非线性因果交互作用,本文提出一种基于连续小波变换和符号传递熵的脑功能网络构建方法.首先,对每导MI-EEG进行连续小波变换,... 详细信息

为有效利用运动想象脑电信号(Motor Imagery Electroencephalogram,MI-EEG)的频域信息并精确反映脑电极之间的非线性因果交互作用,本文提出一种基于连续小波变换和符号传递熵的脑功能网络构建方法.首先,对每导MI-EEG进行连续小波变换,求得其时-频-能量矩阵;然后,将与运动想象密切相关的频带内各频率所对应的时间-能量序列依次拼接,得到各导联的一维时频能量序列;最后,基于任意两电极时频能量序列间的符号传递熵计算连接矩阵,构建脑功能网络.实验结果表明,以电极时频能量序列间的符号传递熵构建的脑功能网络,能够有效反映MIEEG的时频特征和非线性特征信息传递,相比于传统脑网络构建方法,更有利于增强不同运动想象任务的可分性.

关键词：脑-机接口运动想象脑电信号连续小波变换符号传递熵脑功能网络