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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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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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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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Integrated Equipment with Functions of Current Flow Control and Fault Isolation for Multiterminal DC Grids
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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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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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Isolation and Preliminary Characterization of Staphylococcus aureus Lytic Phages from Wastewater Environment in Bobo-Dioulasso, Burkina Faso, West Africa
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作者 Kobo Gnada Michel Kiréopori Gomgnimbou +1 位作者 Raymond Karlhis Yao Christiane Essoh 《Advances in Microbiology》 2025年第1期42-57,共16页
Staphylococcus aureus (S. aureus) is a bacterial pathogen for humans and animals. These bacteria can resist against many antibiotics and this resistance constitute an alarming worldwide human health threat due to the ... Staphylococcus aureus (S. aureus) is a bacterial pathogen for humans and animals. These bacteria can resist against many antibiotics and this resistance constitute an alarming worldwide human health threat due to the morbidity and mortality. Phage therapy is one of the alternative treatments. The aim of this study was to isolate and characterize lytic phages of S. aureus from different wastewater sources in Bobo-Dioulasso, Burkina Faso. Eight strains of S. aureus were isolated from different clinical samples and were used to isolate phages. The isolation and host range of phages were done by the spot test. Phages were purified by the double-layer method. Similar phages after the determination of the host range were characterized using restriction enzymes. A total of 27 phages were obtained after isolation and purification. Nine of the 27 isolates reported a broad host range (≥67%). The results of enzymatic digestion allowed to consider that all phage isolates that presented the same host range and the same genetic fingerprint are the same phage strain;whereas phages that presented the same host range and different genetic fingerprints are different phage strains. Thus, a total of 15 distinct phages isolates specific to S. aureus were characterized. This study highlighted the abundance and lytic capacity of phages isolated from wastewater from Bobo-Dioulasso’s environment against clinical strains of S. aureus. The lytic capacity of these Staphyphages could be an effective alternative tool to combat bacteria multi-resistance. 展开更多
关键词 Staphylococcus aureus Lytic Phages WASTEWATER isolation Burkina Faso
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3D Printed Gear-Based Quasi-Zero Stiffness Vibration Isolation Metastructure
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作者 Gexin Wang Jianyang Li +5 位作者 Yan Liu Kunyan Wang Luquan Ren Qingping Liu Lei Ren Bingqian Li 《Journal of Bionic Engineering》 2025年第2期767-782,共16页
Traditional linear vibration isolators struggle to combine high load-bearing capacity with low-frequency vibration isolation, whereas nonlinear metastructure isolators can effectively fulfill both functions. This pape... Traditional linear vibration isolators struggle to combine high load-bearing capacity with low-frequency vibration isolation, whereas nonlinear metastructure isolators can effectively fulfill both functions. This paper draws inspiration from the Quasi-Zero Stiffness (QZS) characteristics resulting from the buckling deformation of beams, and proposes a gear-based QZS structure by arranging beams in a circular array. We investigated the static mechanical behavior under different structural parameters, loading angles, and gear combinations through experiments and simulations, and demonstrated the mechanical performances could be effectively programmed. Subsequent vibration isolation tests on the double gears prove superior vibration isolation performance at low frequency while maintaining high load-bearing capacities. Additionally, a key contribution of our work is the development of a mathematical model to characterize the buckling behavior of the unit beam within the gear structure, with its accuracy validated through finite element analysis and experimental results. The gear’s modulus, number of teeth, and pressure angle are selected according to standard series, allowing the gear can be seamlessly integrated into existing mechanical systems in critical fields such as aerospace, military, and etc. 展开更多
关键词 3D Printing Vibration isolation Quasi-zero stiffness GEAR Metastructure
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Panax notoginseng polysaccharides: a review focusing on the extraction, isolation, structural characterization, biological activities, and applications
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作者 Jiaqi Huang Yuheng Zhao +6 位作者 Mengyao Wang Xiaojin Tian Dianxin Cui Qilong Wang Xue Li Honghua Wu Wenzhi Yang 《Acupuncture and Herbal Medicine》 2025年第1期23-35,共13页
Panax notoginseng is a traditional Chinese medicine containing various constituents,including the saponins,polysaccharides,polyacetylenes,amino acids,etc.It has beneficial functions,such as the anti-inflammatory,antit... Panax notoginseng is a traditional Chinese medicine containing various constituents,including the saponins,polysaccharides,polyacetylenes,amino acids,etc.It has beneficial functions,such as the anti-inflammatory,antitumor,hepatoprotective,and anti-aging effects.Among these,P.notoginseng polysaccharides(PNPs)have been exploited because of their extensive pharmacological effects,being ranked as one of the current research hotspots,especially for the functional foods and medical practice.In this review,the literature related to PNPs in the past 20 years was surveyed and analyzed using both the China National Knowledge Infrastructure(CNKI)and Web of Science(WOS)databases.The visualization diagram shows that current studies on PNPs mainly focus on the antioxidant and immunomodulatory activities and structural characterization.In addition,the extraction,separation,purification,chemical analysis,structural characteristics,bioactivities,and applications of PNPs are outlined,in detail,aimed to provide valuable information for the further study,development,and utilization regarding PNPs. 展开更多
关键词 Biological activity EXTRACTION isolation Panax notoginseng polysaccharides Structural characterization
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Novel approach to pulmonary vein isolation ablation via right internal jugular access:A case report
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作者 John R Lester Ali Abolhassani +1 位作者 Himax Patel Haitham Hreibe 《World Journal of Cardiology》 2025年第7期203-208,共6页
BACKGROUND Atrial fibrillation(AF)is the most common cardiac arrhythmia worldwide,hosting numerous serious possible complications such as stroke and heart failure.In the past two decades,managing rhythm control was mo... BACKGROUND Atrial fibrillation(AF)is the most common cardiac arrhythmia worldwide,hosting numerous serious possible complications such as stroke and heart failure.In the past two decades,managing rhythm control was more successful via pulmonary vein isolation(PVI)ablation,generally performed via transfemoral access.Patients with anatomical variations may necessitate a dose of creativity and evidence-based techniques.To our knowledge,we present the first PVI case in a patient with AF via right internal jugular(IJ)vein access using pulse field ablation.CASE SUMMARY A 76-year-old male with an extensive medical history notable for type 2 diabetes and severe peripheral vascular disease requiring vascular bypass surgery is identified to have paroxysmal AF.Given functional decline and worsening arrhythmia burden refractory to oral antiarrhythmics,an initial PVI ablation was attempted but failed as the catheter could not be advanced secondary to bilateral iliac vein occlusions.This necessitated a novel approach and a subsequent PVI ablation via the right IJ vein was successful without any complications.The success of this case highlights the feasibility of an IJ approach for PVI in patients where traditional access is not possible.This case can be used as a reference for other practitioners who may face similar challenges when attempting to perform PVI for AF or similar procedures requiring access to similar anatomical locations.CONCLUSION The success of this case highlights the feasibility of an IJ approach for PVI when traditional access is impossible. 展开更多
关键词 Atrial fibrillation Pulmonary vein isolation Ablation Internal jugular Case report
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Associations of social isolation with sleep duration and sleep quality in the elderly:Mediating influence of depression
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作者 Hong-Ying Yang Lian Li +1 位作者 Lu-Jie Yu Guo-Lin Bian 《World Journal of Psychiatry》 2025年第4期216-223,共8页
BACKGROUND Sleep disorders are common health problems in the elderly.The effect of social isolation on sleep duration and sleep quality remains unclear in the Chinese community-dwelling elderly.AIM To explore the asso... BACKGROUND Sleep disorders are common health problems in the elderly.The effect of social isolation on sleep duration and sleep quality remains unclear in the Chinese community-dwelling elderly.AIM To explore the associations of social isolation with sleep duration and sleep quality in community-dwelling elderly people.METHODS A total of 7762 community-dwelling elderly people aged 60 years and older in Ningbo were recruited from June 2022 to August 2022.Data were collected using a questionnaire.Multivariate logistic regression was used to analyze the associations of social isolation with sleep duration and sleep quality.The KHB mediating effect model was used to test the mediating effect of depression and anxiety on these associations.RESULTS Among the participants,2656(34.2%)had abnormal sleep duration(<6 hours or>8 hours),1115(14.4%)had poor sleep quality,and 917(11.8%)had social isolation.After adjusting for confounding factors,compared with the elderly without social isolation,the odds ratios(95%CI)of abnormal sleep duration and poor sleep quality in the elderly with social isolation were 1.49(1.29-1.73)and 1.32(1.09-1.59),respectively.Depression partially mediated the associations of social isolation with sleep duration and sleep quality,accounting for 5.68%and 9.87%of the mediating effect,respectively.CONCLUSION Social isolation was found to be associated with sleep duration and sleep quality in community-dwelling elderly people.More attention should be paid to social isolation in the elderly. 展开更多
关键词 Older adults Sleep duration Sleep quality Social isolation DEPRESSION
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Association of Loneliness and Social Isolation with Ischemic Heart Disease: A Bidirectional and Network Mendelian Randomization Study
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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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Experimental Investigation on the Mechanical Properties of Silicone Elastomers Filled with Fumed Silica for Seismic Isolation Bearings
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作者 Arthur Ramandalina Ji Dang 《Journal of Building Material Science》 2025年第1期44-61,共18页
Laminated elastomeric bearings used in seismic isolation rely on the mechanical properties of their constituent elastomers to ensure effective performance.However,despite their resistance to temperature fluctuations a... Laminated elastomeric bearings used in seismic isolation rely on the mechanical properties of their constituent elastomers to ensure effective performance.However,despite their resistance to temperature fluctuations and environmental aggressors,silicone elastomers exhibit relatively low stiffness,limiting their direct applicability in seismic isolation.This study investigates the effect of fumed silica as a reinforcing filler to enhance the mechanical properties of laminated silicone elastomeric bearings.Elastomeric samples were fabricated with varying fumed silica proportions and subjected to Shore A hardness,uniaxial tensile,and lap shear tests to assess the influence of filler content.Additionally,quasi-static tests were conducted on reduced-scale bearing prototypes under combined vertical compression and cyclic horizontal shear to evaluate their seismic isolation performance.The results demonstrate that fumed silica reinforcement significantly increases stiffness,as evidenced by higher Shore A hardness values.However,a trade-off was observed in tensile properties,with reductions in tensile strength and elongation at break.Despite this,the equivalent elastic modulus did not show substantial variation up to large deformations,indicating that stiffness is preserved under most working conditions.Lap shear tests showed that fumed silica improves shear resistance,while quasi-static tests revealed inelastic behavior with small increases in equivalent shear coefficients but no substantial loss in damping ratios.These findings suggest that fumed silica reinforcement enhances silicone elastomers’stiffness and shear resistance while maintaining moderate damping properties,making it a promising approach for improving the mechanical performance of elastomeric bearings in seismic isolation applications. 展开更多
关键词 Silicone Elastomer Fumed Silica Elastomeric Bearing Seismic isolation Experimental Study
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Efficacy of visual double-lumen bronchial catheter in teaching lung isolation
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作者 Minhao Zhang Halisa Paerhati +4 位作者 Miao Zhou Jiahui Chen Zhiyan Wang Lianbing Gu Pengyi Li 《Progress in Medical Education》 2025年第1期23-31,共9页
Objective:To assess the effectiveness of a visual double-lumen bronchial catheter in teaching lung isolation skills to anesthesia resident trainees.Methods:Between September 2023 and September 2024,20 anesthesiology r... Objective:To assess the effectiveness of a visual double-lumen bronchial catheter in teaching lung isolation skills to anesthesia resident trainees.Methods:Between September 2023 and September 2024,20 anesthesiology residents from Jiangsu Cancer Hospital were randomly divided into two groups:the visual double-lumen group(n=10)and the conventional double-lumen group(n=10).Randomization was achieved using a random number table.The study assessed several outcomes,including total intubation time,positioning time,one-time intubation success rate,intraoperative catheter displacement rate,surgeon satisfaction scores,and the incidence of postoperative complications(pharyngeal pain,hoarseness,and dry cough)within 24 hours.Results:The visual double-lumen group demonstrated superior results compared to the conventional double-lumen group in the following measures:total intubation time(70.2±11.8 s vs 224.9±35.6 s),positioning time(30.1±5.7s vs 176.6±26.4 s),one-time intubation success rate(85%vs 45%),intraoperative catheter displacement rate(10%vs 40%),surgeon’s intubation satisfaction score(8.10±1.07 vs 6.90±1.41),satisfaction score for pulmonary isolation(8.35±1.04 vs 6.55±1.36),and airway management satisfaction score(8.40±1.3 vs 6.70±1.34).Additionally,the incidence of postoperative pharyngeal pain(15%vs 45%),hoarseness(10%vs 40%),and dry cough(5%vs 35%)was significantly lower in the visual double-lumen group(all P<0.05).Conclusion:The visual double-lumen bronchial catheter significantly enhances the training of anesthesia residents in lung isolation by reducing intubation and positioning times,improving intubation success rate,increasing surgeon satisfaction,and reducing intubation-related complications.This method offers a more effective teaching approach compared to conventional techniques. 展开更多
关键词 Visual double-lumen catheter pulmonary isolation educational techniques teaching effect standardized residency training
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Isolation methods of exosomes derived from dental stem cells
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作者 Paras Ahmad Nathan Estrin +2 位作者 Nima Farshidfar Yufeng Zhang Richard J.Miron 《International Journal of Oral Science》 2025年第4期487-504,共18页
Mesenchymal stem cells are highly regarded for their potential in tissue repair and regenerative medicine due to their multipotency and self-renewal abilities.Recently,mesenchymal stem cells have been redefined as“me... Mesenchymal stem cells are highly regarded for their potential in tissue repair and regenerative medicine due to their multipotency and self-renewal abilities.Recently,mesenchymal stem cells have been redefined as“medical signaling cells,”with their primary biological effects mediated through exosome secretion.These exosomes,which contain lipids,proteins,RNA,and metabolites,are crucial in regulating various biological processes and enhancing regenerative therapies.Exosomes replicate the effects of their parent cells while offering benefits such as reduced side effects,low immunogenicity,excellent biocompatibility,and high drug-loading capacity.Dental stem cells,including those from apical papilla,gingiva,dental pulp,and other sources,are key contributors to exosome-mediated regenerative effects,such as tumor cell apoptosis,neuroprotection,angiogenesis,osteogenesis,and immune modulation.Despite their promise,clinical application of exosomes is limited by challenges in isolation techniques.Current methods face issues of complexity,inefficiency,and insufficient purity,hindering detailed analysis.Recent advancements,such as micro-electromechanical systems,alternating current electroosmosis,and serum-free three-dimensional cell cultures,have improved exosome isolation efficacy.This review synthesizes nearly 200 studies on dental stem cell-derived exosomes,highlighting their potential in treating a wide range of conditions,including periodontal diseases,cancer,neurodegenerative disorders,diabetes,and more.Optimized isolation methods offer a path forward for overcoming current limitations and advancing the clinical use of exosome-based therapies. 展开更多
关键词 stem cells EXOSOMES isolation methods mesenchymal stem cells regenerative medicine regulating various biological processes enhancing regenerative therapiesexosomes dental stem cells
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Effect of perioperative disinfection and isolation measures in infection control after gastrointestinal surgery: A retrospective analysis
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作者 Hai-Yan Wang Yan Zou +2 位作者 Li-Ya Shi Xue Qin Li-Juan Hong 《World Journal of Gastrointestinal Surgery》 2025年第5期184-191,共8页
BACKGROUND The application of perioperative disinfection and isolation measures to patients undergoing gastrointestinal surgery with postoperative infection can provide a data reference for reducing the postoperative ... BACKGROUND The application of perioperative disinfection and isolation measures to patients undergoing gastrointestinal surgery with postoperative infection can provide a data reference for reducing the postoperative infection rate,improving post-operative biochemical markers,and enhancing postoperative recovery outcomes.AIM To explore the effectiveness of perioperative disinfection and isolation measures in controlling postoperative infection following gastrointestinal surgery.It also sought to compare infection rates and biochemical markers between the obser-vation and control groups and evaluate the impact of disinfection and isolation measures on reducing postoperative complications.METHODS A retrospective analysis was conducted.Ninety-six patients who underwent gastrointestinal surgery between January 2022 and December 2023 were selected and divided into an observation group and a control group,with 48 cases in each.The observation group received disinfection and isolation measures during the perioperative period,whereas the control group received standard nursing care.The incidence of infection,white blood cell count,C-reactive protein levels,hemoglobin levels,and liver function markers(alanine aminotransferase,aspartate aminotransferase,creatinine,and blood urea nitrogen)were monitored postoperatively in both groups.RESULTS The postoperative infection rate in the observation group was significantly lower than that in the control group(P<0.05).White blood cell and C-reactive protein levels decreased significantly after surgery in the observation group and were significantly lower than those in the control group(P<0.05).Alanine aminotransferase,aspartate aminotransferase,creatinine,and blood urea nitrogen levels in the observation group were lower than those in the control group on postoperative days 1 and 3,showing a significant difference(P<0.05).CONCLUSION Perioperative disinfection and isolation measures effectively reduce postoperative infection rates in gastrointestinal surgery patients and improve biochemical markers,thereby enhancing recovery outcomes.This study provides a valuable basis for postoperative infection control and has significant clinical applications. 展开更多
关键词 PERIOPERATIVE Disinfection and isolation measures Gastrointestinal surgery Postoperative infection Postoperative recovery outcomes
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Research on Innovative Design and Preparation Technology of Power Integrated Isolation Structure
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作者 Yili Xu Xin Li +3 位作者 Xiaodong Yin Guowei Zhang Jingyi Li Qianqian Liu 《Journal of Electronic Research and Application》 2025年第3期214-221,共8页
Power integrated isolation structures play a crucial role in the field of power electronics,especially in silicon carbide(SiC)devices,where challenges such as high leakage current and insufficient voltage endurance ar... Power integrated isolation structures play a crucial role in the field of power electronics,especially in silicon carbide(SiC)devices,where challenges such as high leakage current and insufficient voltage endurance are prevalent.This paper introduces a novel isolation technology based on vanadium ion implantation,achieving high-performance SiC monolithic integration through deep energy level trapping engineering and three-dimensional composite isolation design.The core technologies include:semi-insulating layer+dielectric trench co-isolation,high-precision process control,high-temperature compatibility optimization,ultra-high breakdown field strength,support for 10kV class IGBT/MOSFET integration,and a 30-50%increase in chip area utilization,combining high performance with low-cost advantages. 展开更多
关键词 Silicon carbide Power integration Full enclosure isolation Vanadium ion injection Dielectric backfilling
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Seismic isolation design and resilience improvement of railway station considering the influence of near-fault pulse-like ground motions
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作者 Pan Yi Song Jiayu +1 位作者 Chen Qi Liu Yongxin 《Earthquake Engineering and Engineering Vibration》 2025年第1期257-270,共14页
To improve the resilience of railway stations,a typical station was selected as the research object,and an isolation design was introduced.Twenty-four groups of near-fault pulse-like ground motions were selected.The s... To improve the resilience of railway stations,a typical station was selected as the research object,and an isolation design was introduced.Twenty-four groups of near-fault pulse-like ground motions were selected.The seismic resilience of the no-isolation railway stations(NIRS)and the isolation railway stations(IRS)were compared to provide a numerical result of the improvement in resilience.The results show that in the station isolation design,the station's functional requirements and structural characteristics should be considered and the appropriate placement of isolation bearings is under the waiting room.Under the action of a rare earthquake,the repair cost,repair time,rate of harm and death of the IRS were decreased by 8.04 million,18.30 days,6.93×10^(-3)and 1.21×10^(-3),respectively,when compared to the NIRS.The IRS received a seismic resilience grade of three-stars and the NIRS only one-star,indicating that rational isolation design improves the seismic resilience of stations.Thus,for the design of stations close to earthquake faults,it is suggested to utilize appropriate isolation techniques to improve their seismic resilience. 展开更多
关键词 railway station near-fault pulse-like ground motion isolation design seismic resilience resilience improvement
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An optimal control method of internal resonances for vibration isolation system using an aperiodic isolator
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作者 Yujun Liu Jing Liu +2 位作者 Guang Pan Qiaogao Huang Baowei Song 《Acta Mechanica Sinica》 2025年第1期175-191,共17页
Periodic isolator is well known for its wave filtering characteristic.While in middle and high frequencies,the internal resonances of the periodic isolator are evident especially when damping is small.This study propo... Periodic isolator is well known for its wave filtering characteristic.While in middle and high frequencies,the internal resonances of the periodic isolator are evident especially when damping is small.This study proposes a novel aperiodic vibration isolation for improving the internal resonances control of the periodic isolator.The mechanism of the internal resonances control by the aperiodic isolator is firstly explained.For comparing the internal resonances suppression effect of the aperiodic isolator with the periodic isolator,a dynamic model combing the rigid machine,the isolator,and the flexible plate is derived through multi subsystem modeling method and transfer matrix method,whose accuracy is verified through the finite element method.The influences of the aperiodicity and damping of the isolator on the vibration isolation performance and internal resonances suppression effect are investigated by numerical analysis.The numerical results demonstrate that vibration attenuation performances of the periodic isolator and aperiodic isolator are greatly over than that of the continuous isolator in middle and high frequencies.The aperiodic isolator opens the stop bandgaps comparing with the periodic isolator where the pass bandgaps are periodically existed.The damping of the isolator has the stop bandgap widening effect on both the periodic isolator and the aperiodic isolator.In addition,a parameter optimization algorithm of the aperiodic isolator is presented for improving the internal resonances control effect.It is shown that the vibration peaks within the target frequency band of the aperiodic isolator are effectively reduced after the optimization.Finally,the experiments of the three different vibration isolation systems are conducted for verifying the analysis work. 展开更多
关键词 Internal resonances Vibration isolation Periodic structure Vibration wave propagation
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Real-Time Fault Detection and Isolation in Power Systems for Improved Digital Grid Stability Using an Intelligent Neuro-Fuzzy Logic
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作者 Zuhaib Nishtar Fangzong Wang +1 位作者 Fawwad Hassan Jaskani Hussain Afzaal 《Computer Modeling in Engineering & Sciences》 2025年第6期2919-2956,共38页
This research aims to address the challenges of fault detection and isolation(FDI)in digital grids,focusing on improving the reliability and stability of power systems.Traditional fault detection techniques,such as ru... This research aims to address the challenges of fault detection and isolation(FDI)in digital grids,focusing on improving the reliability and stability of power systems.Traditional fault detection techniques,such as rule-based fuzzy systems and conventional FDI methods,often struggle with the dynamic nature of modern grids,resulting in delays and inaccuracies in fault classification.To overcome these limitations,this study introduces a Hybrid NeuroFuzzy Fault Detection Model that combines the adaptive learning capabilities of neural networks with the reasoning strength of fuzzy logic.The model’s performance was evaluated through extensive simulations on the IEEE 33-bus test system,considering various fault scenarios,including line-to-ground faults(LGF),three-phase short circuits(3PSC),and harmonic distortions(HD).The quantitative results show that the model achieves 97.2%accuracy,a false negative rate(FNR)of 1.9%,and a false positive rate(FPR)of 2.3%,demonstrating its high precision in fault diagnosis.The qualitative analysis further highlights the model’s adaptability and its potential for seamless integration into smart grids,micro grids,and renewable energy systems.By dynamically refining fuzzy inference rules,the model enhances fault detection efficiency without compromising computational feasibility.These findings contribute to the development of more resilient and adaptive fault management systems,paving the way for advanced smart grid technologies. 展开更多
关键词 Fault detection and isolation(FDI) neuro-fuzzy systems digital grids smart grid resilience power system artificial intelligence(AI)
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