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Isolations and Identifications of Two Psychrotrophs and Preliminary Research on Their Applications
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作者 Huifeng Li Jinhui Huang +2 位作者 Xushen Zhou Chao Lin Yang Luo 《Meteorological and Environmental Research》 CAS 2013年第2期22-25,共4页
[Objective] The research aimed to initially study degradation effect of the CODc, in sewage by two psychrotrophs. [Method] Two psychrotrophs were isolated from the activated sludge of wastewater treatment plant in Tia... [Objective] The research aimed to initially study degradation effect of the CODc, in sewage by two psychrotrophs. [Method] Two psychrotrophs were isolated from the activated sludge of wastewater treatment plant in Tianjin Konggang Economic Area. CODc, degradation ability of the screened psychrotroph was analyzed in simulated domestic wastewater at 6℃. [Result] K 36 was identified as Comamonas testosterone, and K 38 was identified as Serratia fonticola. CODcr degradation abilities of the two strains were different in test. COOcr removal rates of the K 36 and K 38 respectively reached up to 23% and 53%. The measured result of growth rate suggested that two psychrotrophs both had high activities at low temperature. [ Conclusion] K 36 and K 38 had potentials in wastewater treatment application. 展开更多
关键词 Activated sludge Psychrotroph CODer degradation Isolation and identification China
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Mental Health Impacts of the COVID-19 Pandemic: Reflecting on Lockdowns and Social Isolations
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作者 Ali Cheshmehzangi Zhaohui Su +3 位作者 Tong Zou Hengcai Chen Tian Tang Ayotunde Dawodu 《Advances in Infectious Diseases》 2022年第2期193-202,共10页
This brief study explores the diverse and long-term mental impacts of the COVID-19 pandemic on societies worldwide. Based on the recent existing literature, six primary categories of mental effects are identified to v... This brief study explores the diverse and long-term mental impacts of the COVID-19 pandemic on societies worldwide. Based on the recent existing literature, six primary categories of mental effects are identified to verify how people are affected by reoccurring lockdowns and social isolations. The study urges holistic research in this field, suggesting that researchers must not neglect the diversity of mental health impacts and context-specific factors. While long-term mental and psychological impacts are mostly hidden for now, we anticipate them to fuel other health issues already experienced by the vulnerable groups, healthcare units, and those fighting the pandemic at the front line. The paper aims to highlight primary mental health impacts of the COVID-19 pandemic due to reoccurring lockdowns and social isolations. This is an opinion paper reflecting on ongoing research related to mental health issues of the ongoing pandemic, some of that could be looked at through case study research or extended research and comparative studies. This brief study suggests further case study-based analysis to evaluate the impacts of lockdowns and social isolations on societal wellbeing and mental health. Globally, the ongoing pandemic has made public health unstable and is expected to continue with its long-term consequences on societies. Research studies should help make governments and policymakers more aware of such long-term consequences to ensure they can respond more effectively to foreseeing public health issues. 展开更多
关键词 COVID-19 Mental Health Lockdown RESPONSE Public Health Social Isolation
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Joint Associations of Sarcopenia and Social Isolation with Mortality:Two Prospective Cohort Studies across Different Cultural Contexts
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作者 Juanjuan Li Zhe Zhang +6 位作者 Jijuan Zhang Yuxiang Wang Hancheng Yu Gang Liu An Pan Yunfei Liao Tingting Geng 《Biomedical and Environmental Sciences》 2026年第1期3-14,共12页
Objective This study aims to investigate the joint associations of sarcopenia and social isolation with mortality risk.Methods Using data from the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and the UK Biobank... Objective This study aims to investigate the joint associations of sarcopenia and social isolation with mortality risk.Methods Using data from the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and the UK Biobank,sarcopenia was diagnosed according to European and Asian Working Groups for Sarcopenia criteria.Social isolation was assessed using standardized questionnaires,including questions on solitude,frequency of social activities,contact with others,and marital status(for the CLHLS only).Results During the follow-up period,8,249 deaths occurred in the CLHLS and 26,670 deaths in the UK Biobank groups.While no significant interaction was observed between sarcopenia and social isolation in predicting all-cause mortality in the CLHLS cohort,the association between social isolation and mortality was stronger among individuals with sarcopenia in the UK Biobank(P-interaction=0.03,relative risk due to interaction:0.23,95%confidence interval[CI]:0.06–0.41).Further joint analyses showed that participants with sarcopenia and high levels of social isolation had the highest mortality risk(hazard ration[HR]:1.99;95%CI:[1.74–2.28]in the CLHLS and 1.69[1.55–1.85]in the UK Biobank)compared to those without either condition.Conclusion The combination of social isolation and sarcopenia synergistically increases the risk of mortality in middle-aged and older adults across diverse populations. 展开更多
关键词 SARCOPENIA Social isolation MORTALITY UK Biobank CLHLS
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Key role of Levitt’s carbon monoxide breath test in revealing coexistent Gilbert syndrome and erythropoietic protoporphyria:A case report
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作者 Ling-Ling Kang Hou-De Zhang 《World Journal of Clinical Cases》 2026年第1期28-33,共6页
It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and er... It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and erythropoietic protoporphyria(EPP),which has not been previously documented.CASE SUMMARY We present a rare case of coexisting GS and EPP in a 23-year-old Chinese male with a long history of jaundice and recently found splenomegaly.Serial nonspecific hemolysis screening tests yielded inconsistent results,and investigations for common hemolytic etiologies were negative.However,Levitt’s carbon monoxide breath test,which measures erythrocyte lifespan(the gold-standard marker of hemolysis),demonstrated significant hemolysis,revealing a markedly shortened erythrocyte lifespan of 11 days(normal average 120 days).Genetic testing subsequently confirmed EPP with a homozygous ferrochelatase gene mutation and GS with a heterozygous uridine diphosphate glucuronosyl trans-ferase 1A1 gene mutation.CONCLUSION The rapid,non-invasive Levitt’s carbon monoxide breath test resolved the diagnostic challenge posed by a rare and complex cause of hyperbilirubinemia. 展开更多
关键词 Isolated hyperbilirubinemia Erythropoietic protoporphyria Gilbert syndrome HEMOLYSIS Levitt’s carbon monoxide breath test Erythrocyte lifespan Case report
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Non-reciprocal Synchronization in Thermal Rydberg Ensembles
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作者 Yunlong Xue Zhengyang Bai 《Chinese Physics Letters》 2026年第1期26-30,共5页
Optical non-reciprocity is a fundamental phenomenon in photonics.It is crucial for developing devices that rely on directional signal control,such as optical isolators and circulators.However,most research in this fie... Optical non-reciprocity is a fundamental phenomenon in photonics.It is crucial for developing devices that rely on directional signal control,such as optical isolators and circulators.However,most research in this field has focused on systems in equilibrium or steady states.In this work,we demonstrate a room-temperature Rydberg atomic platform where the unidirectional propagation of light acts as a switch to mediate time-crystalline-like collective oscillations through atomic synchronization. 展开更多
关键词 atomic synchronization non reciprocal synchronization optical non reciprocity optical isolators thermal Rydberg ensembles directional signal controlsuch time crystalline oscillations unidirectional propagation light
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Enzymatic and non-enzymatic isolationsystems for adipose tissue-derived cells:current state of the art 被引量:5
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作者 Eleni Oberbauer Carolin Steffenhagen +3 位作者 Christoph Wurzer Christian Gabriel Heinz Redl Susanne Wolbank 《Cell Regeneration》 2015年第1期61-74,共14页
In the past decade, adipose tissue became a highly interesting source of adult stem cells for plastic surgery andregenerative medicine. The isolated stromal vascular fraction (SVF) is a heterogeneous cell population i... In the past decade, adipose tissue became a highly interesting source of adult stem cells for plastic surgery andregenerative medicine. The isolated stromal vascular fraction (SVF) is a heterogeneous cell population including theadipose-derived stromal/stem cells (ASC), which showed regenerative potential in several clinical studies and trials.SVF should be provided in a safe and reproducible manner in accordance with current good manufacturing practices(cGMP). To ensure highest possible safety for patients, a precisely defined procedure with a high-quality control isrequired. Hence, an increasing number of adipose tissue-derived cell isolation systems have been developed.These systems aim for a closed, sterile, and safe isolation process limiting donor variations, risk for contaminations,and unpredictability of the cell material. To isolate SVF from adipose tissue, enzymes such as collagenase are used.Alternatively, in order to avoid enzymes, isolation systems using physical forces are available. Here, we provide anoverview of known existing enzymatic and non-enzymatic adipose tissue-derived cell isolation systems, which arepatented, published, or already on the market. 展开更多
关键词 Human adipose tissue Stromal vascular fraction Adipose-derived stromal/stem cells ENZYMATIC NON-ENZYMATIC Isolation systems
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Utilizing engineered extracellular vesicles as delivery vectors in the management of ischemic stroke:a special outlook on mitochondrial delivery 被引量:1
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作者 Jiali Chen Yiyang Li +7 位作者 Xingping Quan Jinfen Chen Yan Han Li Yang Manfei Zhou Greta Seng Peng Mok Ruibing Wang Yonghua Zhao 《Neural Regeneration Research》 SCIE CAS 2025年第8期2181-2198,共18页
Ischemic stroke is a secondary cause of mortality worldwide,imposing considerable medical and economic burdens on society.Extracellular vesicles,serving as natural nanocarriers for drug delivery,exhibit excellent bioc... Ischemic stroke is a secondary cause of mortality worldwide,imposing considerable medical and economic burdens on society.Extracellular vesicles,serving as natural nanocarriers for drug delivery,exhibit excellent biocompatibility in vivo and have significant advantages in the management of ischemic stroke.However,the uncertain distribution and rapid clearance of extracellular vesicles impede their delivery efficiency.By utilizing membrane decoration or by encapsulating therapeutic cargo within extracellular vesicles,their delivery efficacy may be greatly improved.Furthermore,previous studies have indicated that microvesicles,a subset of large-sized extracellular vesicles,can transport mitochondria to neighboring cells,thereby aiding in the restoration of mitochondrial function post-ischemic stroke.Small extracellular vesicles have also demonstrated the capability to transfer mitochondrial components,such as proteins or deoxyribonucleic acid,or their sub-components,for extracellular vesicle-based ischemic stroke therapy.In this review,we undertake a comparative analysis of the isolation techniques employed for extracellular vesicles and present an overview of the current dominant extracellular vesicle modification methodologies.Given the complex facets of treating ischemic stroke,we also delineate various extracellular vesicle modification approaches which are suited to different facets of the treatment process.Moreover,given the burgeoning interest in mitochondrial delivery,we delved into the feasibility and existing research findings on the transportation of mitochondrial fractions or intact mitochondria through small extracellular vesicles and microvesicles to offer a fresh perspective on ischemic stroke therapy. 展开更多
关键词 delivery engineering extracellular vesicles identification ischemic stroke isolation MITOCHONDRIA targeting strategy therapeutic effects
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Integrated Equipment with Functions of Current Flow Control and Fault Isolation for Multiterminal DC Grids 被引量:1
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作者 Shuo Zhang Guibin Zou 《Energy Engineering》 EI 2025年第1期85-99,共15页
The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow ... The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow controller(CFC)are demanded to ensure the multiterminal DC grid to operates reliably and flexibly.However,since the CFC and the DCCB are all based on fully controlled semiconductor switches(e.g.,insulated gate bipolar transistor,integrated gate commutated thyristor,etc.),their separation configuration in the multiterminal DC grid will lead to unaffordable implementation costs and conduction power losses.To solve these problems,integrated equipment with both current flow control and fault isolation abilities is proposed,which shares the expensive and duplicated components of CFCs and DCCBs among adjacent lines.In addition,the complicated coordination control of CFCs and DCCBs can be avoided by adopting the integrated equipment in themultiterminal DC grid.In order to examine the current flow control and fault isolation abilities of the integrated equipment,the simulation model of a specific meshed four-terminal DC grid is constructed in the PSCAD/EMTDC software.Finally,the comparison between the integrated equipment and the separate solution is presented a specific result or conclusion needs to be added to the abstract. 展开更多
关键词 Integrated equipment multiterminal direct current grid current flow control fault isolation
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Programmable Quasi-Zero-Stiffness Metamaterials 被引量:1
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作者 Wenlong Liu Sen Yan +5 位作者 Zhiqiang Meng Lingling Wu Yong Xu Jie Chen Jingbo Sun Ji Zhou 《Engineering》 2025年第4期160-167,共8页
Quasi-zero-stiffness(QZS)metamaterials have attracted significant interest for application in low-frequency vibration isolation.However,previous work has been limited by the design mechanism of QZS metamaterials,as it... Quasi-zero-stiffness(QZS)metamaterials have attracted significant interest for application in low-frequency vibration isolation.However,previous work has been limited by the design mechanism of QZS metamaterials,as it is still difficult to achieve a simplified structure suitable for practical engineering applications.Here,we introduce a class of programmable QZS metamaterials and a novel design mechanism that address this long-standing difficulty.The proposed QZS metamaterials are formed by an array of representative unit cells(RUCs)with the expected QZS features,where the QZS features of the RUC are tailored by means of a structural bionic mechanism.In our experiments,we validate the QZS features exhibited by the RUCs,the programmable QZS behavior,and the potential promising applications of these programmable QZS metamaterials in low-frequency vibration isolation.The obtained results could inspire a new class of programmable QZS metamaterials for low-frequency vibration isolation in current and future mechanical and other engineering applications. 展开更多
关键词 Quasi-zero stiffness METAMATERIALS Vibration isolation Bionic mechanism
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Machine Learning of Element Geochemical Anomalies for Adverse Geology Identification in Tunnels 被引量:1
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作者 Ruiqi Shao Peng Lin +2 位作者 Zhenhao Xu Fumin Liu Yilong Liu 《Journal of Earth Science》 2025年第3期1261-1276,共16页
Geological analysis,despite being a long-term method for identifying adverse geology in tunnels,has significant limitations due to its reliance on empirical analysis.The quantitative aspects of geochemical anomalies a... Geological analysis,despite being a long-term method for identifying adverse geology in tunnels,has significant limitations due to its reliance on empirical analysis.The quantitative aspects of geochemical anomalies associated with adverse geology provide a novel strategy for addressing these limitations.However,statistical methods for identifying geochemical anomalies are insufficient for tunnel engineering.In contrast,data mining techniques such as machine learning have demonstrated greater efficacy when applied to geological data.Herein,a method for identifying adverse geology using machine learning of geochemical anomalies is proposed.The method was identified geochemical anomalies in tunnel that were not identified by statistical methods.We by employing robust factor analysis and self-organizing maps to reduce the dimensionality of geochemical data and extract the anomaly elements combination(AEC).Using the AEC sample data,we trained an isolation forest model to identify the multi-element anomalies,successfully.We analyzed the adverse geological features based the multi-element anomalies.This study,therefore,extends the traditional approach of geological analysis in tunnels and demonstrates that machine learning is an effective tool for intelligent geological analysis.Correspondingly,the research offers new insights regarding the adverse geology and the prevention of hazards during the construction of tunnels and underground engineering projects. 展开更多
关键词 adverse geology TUNNELS geochemical anomalies machine learning Isolation Forest dimensional reduction
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Association of Loneliness and Social Isolation with Ischemic Heart Disease: A Bidirectional and Network Mendelian Randomization Study 被引量:1
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作者 Shuyao Su Wanyue Wang +3 位作者 Chenxi Yuan Zhennan Lin Xiangfeng Lu Fangchao Liu 《Biomedical and Environmental Sciences》 2025年第3期351-364,共14页
Objective Observational studies have shown inconsistent associations of loneliness or social isolation(SI)with ischemic heart disease(IHD),with unknown mediators.Methods Using data from genome-wide association studies... Objective Observational studies have shown inconsistent associations of loneliness or social isolation(SI)with ischemic heart disease(IHD),with unknown mediators.Methods Using data from genome-wide association studies of predominantly European ancestry,we performed a bidirectional two-sample Mendelian Randomization(MR)study to estimate causal effects of loneliness(N=487,647)and SI traits on IHD(N=184,305).SI traits included whether individuals lived alone,participated in various types of social activities,and how often they had contact with friends or family(N=459,830 to 461,369).A network MR study was conducted to evaluate the mediating roles of 20 candidate mediators,including metabolic,behavioral and psychological factors.Results Loneliness increased IHD risk(OR=2.129;95%confidence interval[CI]:1.380 to 3.285),mediated by body fat percentage,waist-hip ratio,total cholesterol,and low-density lipoprotein cholesterol.For SI traits,only fewer social activities increased IHD risk(OR=1.815;95%CI:1.189 to 2.772),mediated by hypertension,high-density lipoprotein cholesterol,triglycerides,fasting insulin,and smoking cessation.No reverse causality of IHD with loneliness and SI was found.Conclusion These findings suggested more attention should be paid to individuals who feel lonely and have fewer social activities to prevent IHD,with several mediators as prioritized targets for intervention. 展开更多
关键词 Mendelian randomization LONELINESS Social isolation Ischemic heart disease Mediation analyses
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Identification and distribution patterns of the ultra-deep small-scale strike-slip faults based on convolutional neural network in Tarim Basin,NW China 被引量:1
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作者 Hao Li Jun Han +4 位作者 Cheng Huang Lian-Bo Zeng Bo Lin Ying-Tao Yao Yi-Chen Song 《Petroleum Science》 2025年第8期3152-3167,共16页
The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set inco... The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set incorporating innovative fault labels to train a U-Net-structured CNN model,enabling effective identification of small-scale strike-slip faults through seismic data interpretation.Based on the CNN faults,we analyze the distribution patterns of small-scale strike-slip faults.The small-scale strike-slip faults can be categorized into NNW-trending and NE-trending groups with strike lengths ranging 200–5000 m.The development intensity of small-scale strike-slip faults in the Lower Yingshan Member notably exceeds that in the Upper Member.The Lower and Upper Yingshan members are two distinct mechanical layers with contrasting brittleness characteristics,separated by a low-brittleness layer.The superior brittleness of the Lower Yingshan Member enhances the development intensity of small-scale strike-slip faults compared to the upper member,while the low-brittleness layer exerts restrictive effects on vertical fault propagation.Fracture-vug systems formed by interactions of two or more small-scale strike-slip faults demonstrate larger sizes than those controlled by individual faults.All fracture-vug system sizes show positive correlations with the vertical extents of associated small-scale strike-slip faults,particularly intersection and approaching fracture-vug systems exhibit accelerated size increases proportional to the vertical extents. 展开更多
关键词 Small-scale strike-slip faults Convolutional neural network Fault label Isolated fracture-vug system Distribution patterns
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Vibration safety assessment and parameter analysis of buried oil pipelines based on vibration isolation holes under strong surface impact 被引量:1
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作者 Wang Guobo Mei Hua +4 位作者 Wang Jianning He Wei Yin Yao Zhai Yuxin Zuo Pengfei 《Earthquake Engineering and Engineering Vibration》 2025年第1期69-82,共14页
Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numeri... Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numerical parameter analysis is conducted on the key influencing factors of the vibration isolation hole(VIH),which include hole diameter,hole net spacing,hole depth,hole number,hole arrangement,and soil parameters.The results indicate that a smaller ratio of net spacing to hole diameter,the deeper the hole,the multi-row hole,the hole adoption of staggered arrangements,and better site soil conditions can enhance the efficiency of the VIH barrier.The average maximum vibration reduction efficiency within the vibration isolation area can reach 42.2%.The vibration safety of adjacent oil pipelines during a dynamic compaction projection was evaluated according to existing standards,and the measurement of the VIH was recommended to reduce excessive vibration.The single-row vibration isolation scheme and three-row staggered arrangement with the same hole parameters are suggested according to different cases.The research findings can serve as a reference for the vibration safety analysis,assessment,and control of adjacent underground facilities under the influence of strong surface impact loads. 展开更多
关键词 vibration isolation hole buried oil pipeline strong surface impact vibration velocity vibration safety assessment
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Mediating role of health literacy in the relationship between social isolation and psychological distress among pre-frail older adults
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作者 Juan Fang Li-Hui Li +4 位作者 Ming-Qian He Yue Ji Dong-Yan Lu Li-Bing Zhang Jin-Lan Yao 《World Journal of Psychiatry》 SCIE 2025年第1期137-144,共8页
BACKGROUND Frailty has become a significant public health issue.The recent increase in the number of frail older adults has led to increased attention being paid to psycho-logical care services in communities.The soci... BACKGROUND Frailty has become a significant public health issue.The recent increase in the number of frail older adults has led to increased attention being paid to psycho-logical care services in communities.The social isolation of pre-frail older adults can impact their psychological distress.AIM To explore the mediating effect of health literacy between social isolation and psychological distress among communitydwelling older adults with pre-frailty.METHODS This descriptive cross-sectional study was conducted with 254 pre-frail older individuals aged 60 years and over.Social isolation,health literacy,and psycholo-gical distress were comprehensively measured using the Lubben Social Network Scale-6,12-item Short-Form Health Literacy Questionnaire,and the Kessler Psy-chological Distress Scale-10.Data were evaluated using the SPSS 27.0 package program and the PROCESS macro tool.Descriptive statistical analyses,correlation analyses,and bootstrap mediation tests were used to assess associations between the variables.RESULTS The results showed that social isolation had an effect on health literacy among pre-frail older adults(β=0.240,P<0.001),social isolation impact on psycho-logical distress pre-frail older adults(β=-0.415,P<0.001);health literacy was identified effect on psychological distress among pre-frail older persons(β=-0.307,P<0.001).Health literacy partially mediated the relationship between social isolation and psychological distress among community-dwelling older adults with pre-frailty,with a mediation effect of-0.074,accounting for 17.83%of the total effect. 展开更多
关键词 FRAIL Ageing Psychological distress Health literacy Social isolation
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基于Transformer-Isolation Forest的地壳形变异常提取
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作者 王雪鉴 王毅恒 +4 位作者 孙新坡 柳川 加明 赵超 杨超 《计算机科学》 北大核心 2025年第S1期724-729,共6页
GPS地壳变形监测在地震前兆研究中起着至关重要的作用。随着观测数据的积累,传统数据处理方法在大数据处理方面面临挑战。文中提出了一种基于Transformer网络和重构误差训练策略的算法。该算法通过训练Transformer网络学习无地震时的GP... GPS地壳变形监测在地震前兆研究中起着至关重要的作用。随着观测数据的积累,传统数据处理方法在大数据处理方面面临挑战。文中提出了一种基于Transformer网络和重构误差训练策略的算法。该算法通过训练Transformer网络学习无地震时的GPS地壳位移数据,输出正常数据,并将异常时的地震GPS地壳位移数据重构误差输入到Isolation Forest异常检测算法模型中来判别是否是地震异常前兆。从GPS地壳变形数据中提取了2个Mw>5的地震事件前异常,获得了比以往研究更全面且普遍的异常数据现象。统计分析显示,相同地区的观测站在2次地震前的GPS地壳变形数据中存在相似的异常现象,表明相同地区存在相似的地壳形变积累和释放模式。这些发现,强调了通过理解地震机制来提高地震预测和防范的必要性。 展开更多
关键词 地壳形变 异常提取 TRANSFORMER 全球定位系统 Isolation Forest
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Unveiling the impact:COVID-19's influence on bacterial resistance in the Kingdom of Bahrain
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作者 Nermin K Saeed Safiya K Almusawi +1 位作者 Noor A Albalooshi Mohammed Al-Beltagi 《World Journal of Virology》 2025年第1期83-98,共16页
BACKGROUND Antibiotic resistance is a growing global health threat,and understanding local trends in bacterial isolates and their susceptibility patterns is crucial for effective infection control and antimicrobial st... BACKGROUND Antibiotic resistance is a growing global health threat,and understanding local trends in bacterial isolates and their susceptibility patterns is crucial for effective infection control and antimicrobial stewardship.The coronavirus disease 2019(COVID-19)pandemic has introduced additional complexities,potentially influencing these patterns.AIM To analyze trends in bacterial isolates and their antibiotic susceptibility patterns at Salmaniya Medical Complex from 2018 to 2023,with a specific focus on the impact of the COVID-19 pandemic on these trends.METHODS A retrospective analysis of microbiological data was conducted,covering the period from 2018 to 2023.The study included key bacterial pathogens such as Escherichia coli(E.coli),Klebsiella pneumoniae,Acinetobacter baumannii,Pseudomonas aeruginosa,and Staphylococcus aureus,among others.The antibiotic susceptibility profiles of these isolates were assessed using standard laboratory methods.To contextualize the findings,the findings were compared with similar studies from other regions,including China,India,Romania,Saudi Arabia,the United Arab Emirates,Malaysia,and United States.RESULTS The study revealed fluctuating trends in the prevalence of bacterial isolates,with notable changes during the COVID-19 pandemic.For example,a significant increase in the prevalence of Staphylococcus aureus was observed during the pandemic years,while the prevalence of E.coli showed a more variable pattern.Antibiotic resistance rates varied among the different pathogens,with a concerning rise in resistance to commonly used antibiotics,particularly among Klebsiella pneumoniae and E.coli.Additionally,the study identified an alarming increase in the prevalence of multidrug-resistant(MDR)strains,especially within Klebsiella pneumoniae and E.coli isolates.The impact of the COVID-19 pandemic on these trends was evident,with shifts in the frequency,resistance patterns,and the emergence of MDR bacteria among several key pathogens.CONCLUSION This study highlights the dynamic nature of bacterial isolates and their antibiotic susceptibility patterns at Salmaniya Medical Complex,particularly in the context of the COVID-19 pandemic.The findings underscore the need for continuous monitoring and effective anti-microbial stewardship programs to combat the evolving threat of antibiotic resistance.Further research and policy initiatives are required to address the identified challenges and improve patient outcomes in the face of these ongoing challenges. 展开更多
关键词 Multidrug-resistant organisms Antibiotic susceptibility COVID-19 pandemic Antimicrobial stewardship Bacterial isolates Salmaniya Medical Complex Bahrain
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Compact Zigzag Vibration Isolator Based on Additive Manufacturing
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作者 JIA Meng WANG Tingwei DAI Ning 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第S1期121-130,共10页
Devices on aircraft are subjected to complex environmental excitations that pose risks to their operational safety.Passive vibration isolation techniques are extensively employed due to their advantage of not requirin... Devices on aircraft are subjected to complex environmental excitations that pose risks to their operational safety.Passive vibration isolation techniques are extensively employed due to their advantage of not requiring additional energy sources.This paper introduces a novel metallic vibration isolator based on zigzag structures.The proposed isolator features a compact design and can be manufactured using additive manufacturing techniques,allowing for the integration of structural and functional elements.Firstly,the vibration response of the single-degree-of-freedom(SDOF)system is analyzed.To achieve effective vibration reduction,it is crucial for the isolator's stiffness to be sufficiently low.Secondly,to obtain a structure with high compliance,the traversal algorithm and the finite element method(FEM)are applied.The results confirm that the zigzag structure is a reliable high-compliance configuration.Thirdly,the parametric geometric model of the zigzag structure is developed and its stiffness is calculated.Quasi-static compression experiments validate the accuracy of the calculations.Finally,a specific engineering example is considered,where a zigzag vibration isolator is designed and fabricated.Vibration experiments demonstrate that the zigzag isolator effectively reduces both the stiffness and the fundamental frequency of the vibration system,achieving a vibration isolation efficiency exceeding 60%. 展开更多
关键词 vibration isolation passive isolators additive manufacturing zigzag structures metallic vibration isolator
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Discussion on isolation of flexible beams with various support configurations
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作者 Jun-Ning Zhang Xiao-Ye Mao +1 位作者 Hu Ding Li-Qun Chen 《Acta Mechanica Sinica》 2025年第2期216-236,共21页
This work discusses the strain and acceleration suppression of a flexible beam subjected to different supports analytically.As classical protection,the beam is mounted on a vertical linear spring together with a linea... This work discusses the strain and acceleration suppression of a flexible beam subjected to different supports analytically.As classical protection,the beam is mounted on a vertical linear spring together with a linear damper in parallel.This is called linear isolation.To enhance isolation performance,nonlinearity is employed in the boundary.In addition,quasi-zero isolation is established based on the non-linearly enhanced one by adjusting the installation length of the horizontal spring.To discuss their performance fully and fairly,the amplitude,the acceleration,the potential energy of the beam,the input work of the excitation,the dissipation work of the beam,and the dynamics stress along the beam are investigated based on the same parameters.The comparison shows that all these isolations can protect the beam with high efficiency,even when the basement excitation is tiny.Although the linear isolation and the nonlinearly enhanced one will arouse two resonance peaks on both sides of the primary resonance of the beam without isolation,the maximum amplitudes of them are reduced a lot.But for the low frequency excitation,the quasi-zero isolation has the best performance as it drives the primary resonance to the high frequency region.The simulation shows that the beam needs a relatively soft isolation to avoid the damage caused by the shock vibration,including the quasi-zero one.In general,the quasi-zero isolation shows the best performance.The nonlinearly enhanced one is the suboptimal choice.The present work shows the capacities of three isolations for a flexible beam by the steady-state response and the shock vibration.It provides design suggestions for the isolation of flexible beams. 展开更多
关键词 Flexible continuum Boundary isolation Quasi-zero isolation Nonlinear isolation Linear isolation
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Trends and emerging techniques in isolated power converters
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作者 Lin Cheng Dongfang Pan 《Journal of Semiconductors》 2025年第7期6-9,共4页
Isolated power converters have emerged as an active research topic in power integrated circuit(IC)design.Reflecting this growing interest,ISSCC 2025 has featured a dedicated session on"Isolated Power and Gate Dri... Isolated power converters have emerged as an active research topic in power integrated circuit(IC)design.Reflecting this growing interest,ISSCC 2025 has featured a dedicated session on"Isolated Power and Gate Drivers".These converters enable safe and reliable power delivery across voltage domains and are widely used in renewable energy,electric vehicles,and telecommunications.Galvanic isolation prevents surge currents and ground loop issues in harsh high-voltage environments.As demand grows for compact,efficient,and high–power-density solutions,fully integrated architectures featuring on-chip transformers are increasingly favored over traditional module-based designs,offering>5 kV isolation with a smaller footprint and lower system cost[1]. 展开更多
关键词 ISSCC ground loop issues isolated power converters power integrated circuit galvanic isolation emerging techniques surge currents renewable energyelectric
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Genomic evidence of hybridization between two species of Penduline Tits reveals postzygotic reproductive isolation
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作者 Hui Wang Mansour Aliabadian +1 位作者 Zhengwang Zhang De Chen 《Avian Research》 2025年第3期517-518,共2页
The biological species concept defines species as groups of actually or potentially interbreeding natural populations that are reproductively isolated from other such groups(Mayr,1942).Reproductive isolation,whether p... The biological species concept defines species as groups of actually or potentially interbreeding natural populations that are reproductively isolated from other such groups(Mayr,1942).Reproductive isolation,whether prezygotic or postzygotic,plays a central role in maintaining species boundaries.However,hybridization between closely related taxa can challenge these boundaries and provide insight into speciation,gene flow,and evolutionary processes(Coyne and Orr,2004). 展开更多
关键词 postzygotic reproductive isolation closely related taxa HYBRIDIZATION genomic evidence reproductive isolation SPECIATION biological species concept gene flow
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