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Combined prevention and treatment measures are essential to control nosocomial infections during the COVID-19 pandemic
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作者 Jing-Wen Liu Yue-Yue Li +1 位作者 Ming-Ke Wang Ji-Shun Yang 《World Journal of Virology》 2024年第2期11-18,共8页
Severe acute respiratory syndrome coronavirus-2 is a highly contagious positive-sense,single-stranded RNA virus that has rapidly spread worldwide.As of December 17,2023,772838745 confirmed cases including 6988679 deat... Severe acute respiratory syndrome coronavirus-2 is a highly contagious positive-sense,single-stranded RNA virus that has rapidly spread worldwide.As of December 17,2023,772838745 confirmed cases including 6988679 deaths have been reported globally.This virus primarily spreads through droplets,airborne transmission,and direct contact.Hospitals harbor a substantial number of confirmed coronavirus disease 2019(COVID-19)patients and asymptomatic carriers,accompanied by high population density and a larger susceptible population.These factors serve as potential triggers for nosocomial infections,posing a threat during the COVID-19 pandemic.Nosocomial infections occur to varying degrees across different countries worldwide,emphasizing the urgent need for a practical approach to prevent and control the intra-hospital spread of COVID-19.This study primarily concentrated on a novel strategy combining preventive measures with treatment for combating COVID-19 nosocomial infections.It suggests preventive methods,such as vaccination,disinfection,and training of heathcare personnel to curb viral infections.Additionally,it explored therapeutic strategies targeting cellular inflammatory factors and certain new medications for COVID-19 patients.These methods hold promise in rapidly and effectively preventing and controlling nosocomial infections during the COVID-19 pandemic and provide a reliable reference for adopting preventive measures in the future pandemic. 展开更多
关键词 COVID-19 SARS-CoV-2 Nosocomial infection prevention Treatment
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Internal Control Management and Risk Prevention Measures of State-Owned Enterprises
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作者 Bing Liu 《Journal of Electronic Research and Application》 2024年第3期1-6,共6页
As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an... As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an important part of enterprise management,internal control management plays an irreplaceable role.Especially in the current domestic and international economic situation is complex and changeable,market competition is increasingly fierce environment,to strengthen the internal control management of state-owned enterprises and risk prevention measures is particularly important.This paper starts with the importance of internal control management and risk prevention for state-owned enterprises,and analyzes the problems and strategies in the internal control management and risk prevention of state-owned enterprises,in order to build a more comprehensive and efficient risk management system for state-owned enterprises to adapt to the ever-changing market environment and realize sustainable development. 展开更多
关键词 State-owned enterprises Internal control management Risk prevention
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Influencing factors and prevention measures of casing deformation in deep shale gas wells in Luzhou block,southern Sichuan Basin,SW China 被引量:1
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作者 HAN Lingling LI Xizhe +5 位作者 LIU Zhaoyi DUAN Guifu WAN Yujin GUO Xiaolong GUO Wei CUI Yue 《Petroleum Exploration and Development》 SCIE 2023年第4期979-988,共10页
Based on structural distribution and fault characteristics of the Luzhou block,southern Sichuan Basin,as well as microseismic,well logging and in-situ stress data,the casing deformation behaviors of deep shale gas wel... Based on structural distribution and fault characteristics of the Luzhou block,southern Sichuan Basin,as well as microseismic,well logging and in-situ stress data,the casing deformation behaviors of deep shale gas wells are summarized,and the casing deformation mechanism and influencing factors are identified.Then,the risk assessment chart of casing deformation is plotted,and the measures for preventing and controlling casing deformation are proposed.Fracturing-activated fault slip is a main factor causing the casing deformation in deep shale gas wells in the Luzhou block.In the working area,the approximate fracture angle is primarily 10°-50°,accounting for 65.34%,and the critical pore pressure increment for fault-activation is 6.05-9.71 MPa.The casing deformation caused by geological factors can be prevented/controlled by avoiding the faults at risk and deploying wells in areas with low value of stress factor.The casing deformation caused by engineering factors can be prevented/controlled by:(1)keeping wells avoid faults with risks of activation and slippage,or deploying wells in areas far from the faulting center if such avoidance is impossible;(2)optimizing the wellbore parameters,for example,adjusting the wellbore orientation to reduce the shear force on casing to a certain extent and thus mitigate the casing deformation;(3)optimizing the casing program to ensure that the curvature radius of the curved section of horizontal well is greater than 200 m while the drilling rate of high-quality reservoirs is not impaired;(4)optimizing the fracturing parameters,for example,increasing the evasive distance,lowering the single-operation pressure,and increasing the stage length,which can help effectively reduce the risk of casing deformation. 展开更多
关键词 Sichuan Basin Luzhou block shale gas well casing deformation mechanism fault activation risk assessment prevention measure
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Occurrence Characteristics and Prevention and Control Measures of Spodoptera frugiperda in Maize
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作者 Liping DONG Chunming LIU 《Plant Diseases and Pests》 CAS 2023年第3期8-9,共2页
Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and... Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and control,agricultural prevention and control,physical prevention and control,chemical prevention and control,and biological prevention and control can effectively control the damage of S.frugiperda and guarantee the safety of food production.The results will provide some reference for the prevention and control of S.frugiperda. 展开更多
关键词 Spodoptera frugiperda Occurrence characteristics prevention and control measures MAIZE
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Cervical cancer prevention in China: where are we now, and what's next? 被引量:1
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作者 Huijiao Yan Qiankun Wang Youlin Qiao 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第3期213-217,共5页
Cervical cancer(CC) epidemiology CC, the fourth most frequently diagnosed malignancy in women worldwide, is a major global health challenge, particularly in low-resource regions. Approximately 88.1% of the 604,000 CC ... Cervical cancer(CC) epidemiology CC, the fourth most frequently diagnosed malignancy in women worldwide, is a major global health challenge, particularly in low-resource regions. Approximately 88.1% of the 604,000 CC new cases occurred in low-and middle-income countries in 2020, and more than 90% of the 342,000 CC deaths occurred in low-and middle-income countries in 2020~1. 展开更多
关键词 prevention CERVICAL EPIDEMIOLOGY
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HealthMeasures患者报告结局报告清单的解读
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作者 臧娴 宗旭倩 +4 位作者 袁长蓉 王玲 吴傅蕾 张雯 黄青梅 《护士进修杂志》 2024年第10期1088-1092,共5页
美国匹兹堡大学和HealthMeasures指导委员会及PROMIS健康组织标准委员会共同发表了HealthMeasures患者报告结局报告清单,旨在促进不同患者报告结局测量工具的标准化报告,帮助研究人员提高工具报告质量及结果解释的准确性,进一步改善跨... 美国匹兹堡大学和HealthMeasures指导委员会及PROMIS健康组织标准委员会共同发表了HealthMeasures患者报告结局报告清单,旨在促进不同患者报告结局测量工具的标准化报告,帮助研究人员提高工具报告质量及结果解释的准确性,进一步改善跨研究间的比较分析。本文对HealthMeasures患者报告结局报告清单的主要内容进行介绍和解读,以期为中国患者报告结局研究者提供参考和借鉴。 展开更多
关键词 患者报告结局 报告清单 测量工具 标准化 解读
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Influencing factors and preventive measures of infectious complications after intestinal resection for Crohn’s disease
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作者 Shi-Rong Lv Xiao Huang +4 位作者 Li-Yun Zhou Jie Shi Chu-Chu Gong Ming-Ke Wang Ji-Shun Yang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3363-3370,共8页
The incidence of Crohn’s disease(CD)has increased in recent years,with most patients requiring intestinal resection.Complications after intestinal resection for CD can lead to poor prognosis and recurrence,among whic... The incidence of Crohn’s disease(CD)has increased in recent years,with most patients requiring intestinal resection.Complications after intestinal resection for CD can lead to poor prognosis and recurrence,among which infectious complic-ations are the most common.This study aimed to investigate the common risk factors,including medications,preoperative nutritional status,surgery-related factors,microorganisms,lesion location and type,and so forth,causing infectious complications after intestinal resection for CD,and to propose corresponding preventive measures.The findings provided guidance for identifying suscept-ibility factors and the early intervention and prevention of infectious complic-ations after intestinal resection for CD in clinical practice. 展开更多
关键词 Crohn’s disease Intestinal resection Postoperative infectious complications Influencing factors Preventive measures
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Adolescent suicide risk factors and the integration of socialemotional skills in school-based prevention programs 被引量:2
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作者 Xin-Qiao Liu Xin Wang 《World Journal of Psychiatry》 SCIE 2024年第4期494-506,共13页
Adolescents are considered one of the most vulnerable groups affected by suicide.Rapid changes in adolescents’physical and mental states,as well as in their lives,significantly and undeniably increase the risk of sui... Adolescents are considered one of the most vulnerable groups affected by suicide.Rapid changes in adolescents’physical and mental states,as well as in their lives,significantly and undeniably increase the risk of suicide.Psychological,social,family,individual,and environmental factors are important risk factors for suicidal behavior among teenagers and may contribute to suicide risk through various direct,indirect,or combined pathways.Social-emotional learning is considered a powerful intervention measure for addressing the crisis of adolescent suicide.When deliberately cultivated,fostered,and enhanced,selfawareness,self-management,social awareness,interpersonal skills,and responsible decision-making,as the five core competencies of social-emotional learning,can be used to effectively target various risk factors for adolescent suicide and provide necessary mental and interpersonal support.Among numerous suicide intervention methods,school-based interventions based on social-emotional competence have shown great potential in preventing and addressing suicide risk factors in adolescents.The characteristics of school-based interventions based on social-emotional competence,including their appropriateness,necessity,cost-effectiveness,comprehensiveness,and effectiveness,make these interventions an important means of addressing the crisis of adolescent suicide.To further determine the potential of school-based interventions based on social-emotional competence and better address the issue of adolescent suicide,additional financial support should be provided,the combination of socialemotional learning and other suicide prevention programs within schools should be fully leveraged,and cooperation between schools and families,society,and other environments should be maximized.These efforts should be considered future research directions. 展开更多
关键词 Adolescent suicide Risk factors Social-emotional skills Social and emotional learning SCHOOL prevention
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Unlocking the potential-vitamin D in prostate cancer prevention 被引量:1
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作者 Ayun Cassell Solomane Konneh 《World Journal of Clinical Oncology》 2024年第2期169-174,共6页
Prostate cancer poses a significant health challenge globally,demanding proactive prevention strategies.This editorial explores the emerging role of vitamin D in prostate cancer prevention.While traditionally associat... Prostate cancer poses a significant health challenge globally,demanding proactive prevention strategies.This editorial explores the emerging role of vitamin D in prostate cancer prevention.While traditionally associated with bone health,vitamin D is increasingly recognized for its broader impact on immune function,cellular signaling,and cancer prevention.Epidemiological studies suggest an intriguing link between vitamin D deficiency and elevated prostate cancer risk,particularly in regions with limited sunlight exposure.Mechanistically,vitamin D regulates cellular processes,inhibiting unchecked cancer cell growth and bols-tering immune surveillance.Personalized prevention strategies,considering individual factors,are deemed essential for harnessing the full potential of vitamin D.To unlock this potential,the future calls for robust research,public awareness campaigns,dietary improvements,and vigilant medical guidance.Collaborative efforts are poised to pave the way toward a future where vitamin D stands as a sentinel in prostate cancer prevention,ushering in hope and improved health for men worldwide. 展开更多
关键词 CELL CHOLECALCIFEROL prevention Prostate cancer Vitamin D
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Sustainable Community Epidemic Prevention Countermeasures against Public Health Emergencies
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作者 Detai TANG Xinbo YU 《Meteorological and Environmental Research》 CAS 2023年第2期4-7,共4页
How to deal with public health emergencies is an important issue related to the normal life of community residents. However, after the corresponding understanding, it is found that a series of unsustainable epidemic p... How to deal with public health emergencies is an important issue related to the normal life of community residents. However, after the corresponding understanding, it is found that a series of unsustainable epidemic prevention factors have been exposed in the community in the COVID-19, such as blocked access to basic materials, unsafe living environment, and lack of social platforms. In view of these problems, based on Maslow’s hierarchy of needs, the changes in the hierarchy of needs of residents during the epidemic were analyzed, and sustainable community epidemic prevention strategies were proposed from five aspects of material storage, safe environment, social platform, respect opportunity and self-worth realization, so as to provide effective reference for future response to public health emergencies. 展开更多
关键词 Public health emergencies Community epidemic prevention Maslow's hierarchy of needs Epidemic prevention countermeasures
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Navigating nephrotoxic waters:A comprehensive overview of contrast-induced acute kidney injury prevention 被引量:1
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作者 Panagiotis Theofilis Rigas Kalaitzidis 《World Journal of Radiology》 2024年第6期168-183,共16页
Contrast-induced acute kidney injury(CI-AKI)is the third leading cause of acute kidney injury deriving from the intravascular administration of contrast media in diagnostic and therapeutic procedures and leading to lo... Contrast-induced acute kidney injury(CI-AKI)is the third leading cause of acute kidney injury deriving from the intravascular administration of contrast media in diagnostic and therapeutic procedures and leading to longer in-hospital stay and increased short and long-term mortality.Its pathophysiology,although not well-established,revolves around medullary hypoxia paired with the direct toxicity of the substance to the kidney.Critically ill patients,as well as those with pre-existing renal disease and cardiovascular comorbidities,are more susceptible to CI-AKI.Despite the continuous research in the field of CI-AKI prevention,clinical practice is based mostly on periprocedural hydration.In this review,all the investigated methods of prevention are presented,with an emphasis on the latest evidence regarding the potential of RenalGuard and contrast removal systems for CI-AKI prevention in high-risk individuals. 展开更多
关键词 Contrast-induced acute kidney injury Contrast media prevention HYDRATION RenalGuard Dyevert
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Appraisal of Existing HIV/AIDs Prevention and Control Measures and Presentation of Innovative Strategies to End HIV/AIDS Epidemic by 2030
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作者 Mathias Tumwebaze John Rubaihayo Mpairwe Harold 《Open Journal of Epidemiology》 2023年第3期178-194,共17页
Background: Globally, UNAIDS report 2022 shows, there are 84.2 million people affected by HIV/AIDS and 40.1 million deaths from AIDS since the start of epidemic. In sub-Saharan Africa, women and girls accounted for 63... Background: Globally, UNAIDS report 2022 shows, there are 84.2 million people affected by HIV/AIDS and 40.1 million deaths from AIDS since the start of epidemic. In sub-Saharan Africa, women and girls accounted for 63% of all new HIV infections in 2021 with, six in seven new HIV infections among adolescents aged 15 - 19 years being girls. Key populations accounted for 70% of HIV infections globally in 2021, with 51% of these new HIV infections in sub-Saharan Africa. Reflecting on the 4 decades’ journey of HIV epidemic amidst local, national and international efforts, the UN target of ending AIDS as a public health threat by 2030 remains questionable unless new innovative ways are used. This study aimed at analyzing existing HIV/AIDS interventions, discuss UN interventions in line with ending HIV/AIDS by 2030 then, suggest and discuss new innovative ways of ending HIV scourge by 2030. Methods: Systematic literature review methodology was used to extract existing published information on HIV prevention strategies from 1981 to 2023. The articles were previewed by 2 experts for quality and grouped by intervention. Of the 637 articles accessed, on HIV prevention/control only 45 met the inclusion criteria. Data were synthesized using a narrative synthesis approach following standard guidelines on synthesis without meta-analysis. Descriptive analysis was done, strength and limitations were identified. UNAIDS recommendations for ending HIV/AIDS by 2030 identified and analyzed. New Innovations in HIV/AIDS were presented and discussed. The scope of the reviewed literature was limited to HIV preventive strategies practiced between 1981 and 2023. Results: Findings show that, Uganda’s HIV prevalence was at a peak in 1991 of 15% (30% among pregnant women in urban areas). ABC strategy is claimed to have turned sharply downward the prevalence through the mid-1990s and reached 5% (14% for pregnant urban women) by 2001. Analysis of the strategy showed that the achievements of the strategy could not be sustained, subsequently HIV prevalence rose again. This is because none of the ABC components can independently reduce HIV problem. In the real world, 100% abstinence has failed, condom use only reduces infection by 90% (WHO), and lifelong monogamy is impractical. Such limitations weaken ABC strategy. The study established that Post-exposure prophylaxis (PEP) i.e. taking HIV medicines within 72 hours (3 days) after a possible exposure to HIV infection is a safe, effective and a globally practiced HIV preventive intervention in emergency situations of HIV exposure. However, PEP is limited to care sought within 72 hours after exposure and yet timely access especially in rural areas and for key populations remains a big challenge. Oral PrEP was also identified as effective HIV preventive measure that can reduce HIV risk from sex by about 99% and from injection drug users by 74%. However, like PEP, timely access especially in rural areas and for key populations remains a big challenge. The UNAIDS 95-95-95 strategy (i.e. 95% of people know their HIV status, 95% with +HIV status be on sustained ART and 95% on ART get viral load suppression) formed the basis for setting the target of ending HIV/AIDS epidemic by 2030. However, our analysis shows that this target is unrealistic given the above highlighted limitations/ barriers in preventive measures and the unlikely perfect adherence (100%) to ART by all enrolled HIV positive persons. Conclusion: Ending HIV/AIDS by 2030 cannot be achieved by implementing the current preventing strategies and control measures. This study established that most of the existing HIV preventive strategies and control measures have a number of limitations. However, with sustained UN 95-95-95 strategy supplemented with additional innovative ways, there is hope that the UN dream of ending HIV/AIDS though not necessarily by 2030, can in the long run be achieved. 展开更多
关键词 HIV prevention Innovative HIV Strategies UNAIDS 95-95-95 Ending HIV by 2030 ABC Strategy
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Study on the Safety and Prevention Technology of Coal Mining under the River in Xingyuan Coal Mine
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作者 Abdoulaye Sylla Wenbing Guo 《Open Journal of Geology》 CAS 2024年第3期339-402,共64页
Coal mining-induced surface subsidence poses significant ecological and infrastructural challenges, necessitating a comprehensive study to ensure safe mining practices, particularly in underwater conditions. This proj... Coal mining-induced surface subsidence poses significant ecological and infrastructural challenges, necessitating a comprehensive study to ensure safe mining practices, particularly in underwater conditions. This project aims to address the extensive impact of coal mining on the environment, infrastructure, and overall safety, focusing on the Shigong River area above the working face. The study employs qualitative and quantitative analyses, along with on-site engineering measurements, to gather data on crucial parameters such as coal seam characteristics, roof rock lithology, thickness, water resistance, and structural damage degree. The research encompasses a multidisciplinary approach, involving mining, geology, hydrogeology, geophysical exploration, rock mechanics, mine surveying, and computational mathematics. The importance of effective safety measures and prevention techniques is emphasized, laying the foundation for research focused on the Xingyun coal mine. The brief concludes by highlighting the potential economic and social benefits of this project and its contribution to valuable experience for future subsea coal mining. 展开更多
关键词 Coal Mining-Induced Surface Subsidence Ecological and Infrastructural Challenges Safe Mining Practices Underwater Conditions Multidisciplinary Approach Safety measures prevention Techniques
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Beyond dentistry:could prevention and screening for neurodegenerative diseases start in the dental office?
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作者 Francesca R.Buccellato Daniela Galimberti Gianluca M.Tartaglia 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期156-157,共2页
The differential diagnosis of neurodegenerative diseases is complex and relies on clinical assessment,biomarker levels in cerebrospinal fluid,neuroimaging and neuropsychological assessment.The efforts of the scientifi... The differential diagnosis of neurodegenerative diseases is complex and relies on clinical assessment,biomarker levels in cerebrospinal fluid,neuroimaging and neuropsychological assessment.The efforts of the scientific community are focused on two aspects:a)the discovery of minimally invasive biomarkers;b)the discovery of early biomarkers that can predict the progression to clinical disease in the presymptomatic stage of a disease.Considering the impact of the number of patients affected by chronic neurodegenerative diseases on public health expenditures,early diagnosis seems to be a primary need of our society. 展开更多
关键词 diagnosis DISEASES prevention
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Physical activity with or without dietary intervention for the prevention of cardiovascular diseases
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作者 Carl J.Lavie Salvatore Carbone Leandro Slipczuk 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期753-755,共3页
We and others have published extensively on the benefits of physical activity(PA),exercise training,and cardiorespiratory fitness(CRF)to decrease the prevalence of cardiovascular diseases(CVDs)and CVD and all-cause mo... We and others have published extensively on the benefits of physical activity(PA),exercise training,and cardiorespiratory fitness(CRF)to decrease the prevalence of cardiovascular diseases(CVDs)and CVD and all-cause morbidity and mortality.^(1-5)Both PA and CRF are important;however,CRF,which is mostly obtained through PA,although there is a genetic component,seems to be even more important than PA for predicting prognosis.^(1,4-6)Certainly,the wealth of data from across the world has indicated that increasing PA to enhance CRF while mitigating sedentary behavior would go a long way to lessen the world-wide obesity epidemic and reduce CVD and all-cause mortality. 展开更多
关键词 MORTALITY prevention DISEASES
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Community-based prevention and treatment of cardiovascular diseases
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作者 Sheng-Shou HU The Writing Committee of the Report on Cardiovascular Health and Diseases in China 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第3期315-322,共8页
The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in China.This is the third section of the report with a specific focus on community-based prevention a... The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in China.This is the third section of the report with a specific focus on community-based prevention and treatment of cardiovascular diseases(CVD).This section of the report underscores the importance of initiatives outlined in the"Healthy China 2030 Plan,"emphasizing the comprehensive prevention and control strategy for chronic diseases.A key aspect of this plan involves the establishment of national demonstration areas aimed at comprehensive prevention and control of chronic diseases.By 2020,488 such areas had been set up across China,surpassing the initial target and covering a significant proportion of counties and districts.The report highlights the successful implementation of these strategies in Lishan district,Anshan city,where demonstration areas for comprehensive prevention and control of chronic diseases were launched in 2013.Over the course of seven years,the number of healthy units increased substantially,leading to improvements in managing risk factors for CVD among residents.Significant reductions in prevalence rates of overweight,obesity,smoking,passive smoking,and drinking were observed,along with the development of healthier behaviors among residents.Similarly,Qiaokou district in Wuhan City,designated as a national demonstration area in 2014,implemented comprehensive public health promotion initiatives.Notably,special clinics for hypertension intervention were established,contributing to an increase in self-reported rates of hypertension,a slight decrease in prevalence,and a remarkable improvement in the control rate among treated patients.Overall,these efforts underscore the effectiveness of community-based approaches in driving positive health outcomes and advancing the comprehensive prevention and control of chronic diseases,particularly cardiovascular diseases,in China. 展开更多
关键词 prevention DISTRICT TREATMENT
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Applying the Shearlet-Based Complexity Measure for Analyzing Mass Transfer in Continuous-Flow Microchannels
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作者 Elena Mosheva Ivan Krasnyakov 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1743-1758,共16页
Continuous-flow microchannels are widely employed for synthesizing various materials,including nanoparticles,polymers,and metal-organic frameworks(MOFs),to name a few.Microsystem technology allows precise control over... Continuous-flow microchannels are widely employed for synthesizing various materials,including nanoparticles,polymers,and metal-organic frameworks(MOFs),to name a few.Microsystem technology allows precise control over reaction parameters,resulting in purer,more uniform,and structurally stable products due to more effective mass transfer manipulation.However,continuous-flow synthesis processes may be accompanied by the emergence of spatial convective structures initiating convective flows.On the one hand,convection can accelerate reactions by intensifying mass transfer.On the other hand,it may lead to non-uniformity in the final product or defects,especially in MOF microcrystal synthesis.The ability to distinguish regions of convective and diffusive mass transfer may be the key to performing higher-quality reactions and obtaining purer products.In this study,we investigate,for the first time,the possibility of using the information complexity measure as a criterion for assessing the intensity of mass transfer in microchannels,considering both spatial and temporal non-uniformities of liquid’s distributions resulting from convection formation.We calculate the complexity using shearlet transform based on a local approach.In contrast to existing methods for calculating complexity,the shearlet transform based approach provides a more detailed representation of local heterogeneities.Our analysis involves experimental images illustrating the mixing process of two non-reactive liquids in a Y-type continuous-flow microchannel under conditions of double-diffusive convection formation.The obtained complexity fields characterize the mixing process and structure formation,revealing variations in mass transfer intensity along the microchannel.We compare the results with cases of liquid mixing via a pure diffusive mechanism.Upon analysis,it was revealed that the complexity measure exhibits sensitivity to variations in the type of mass transfer,establishing its feasibility as an indirect criterion for assessing mass transfer intensity.The method presented can extend beyond flow analysis,finding application in the controlling of microstructures of various materials(porosity,for instance)or surface defects in metals,optical systems and other materials that hold significant relevance in materials science and engineering. 展开更多
关键词 Shearlet analysis complexity measure entropy measure CONVECTION microchannels double-diffusive instability
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Bunch-length measurement at a bunch-by-bunch rate based on time–frequency-domain joint analysis techniques and its application
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作者 Hong-Shuang Wang Xing Yang +2 位作者 Yong-Bin Leng Yi-Mei Zhou Ji-Gang Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期165-175,共11页
This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage rings.This technique uses the time–frequency-domain joint analysis of the bunch si... This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage rings.This technique uses the time–frequency-domain joint analysis of the bunch signal to obtain bunch-by-bunch and turn-by-turn longitudinal parameters,such as bunch length and synchronous phase.The bunch signal is obtained using a button electrode with a bandwidth of several gigahertz.The data acquisition device was a high-speed digital oscilloscope with a sampling rate of more than 10 GS/s,and the single-shot sampling data buffer covered thousands of turns.The bunch-length and synchronous phase information were extracted via offline calculations using Python scripts.The calibration coefficient of the system was determined using a commercial streak camera.Moreover,this technique was tested on two different storage rings and successfully captured various longitudinal transient processes during the harmonic cavity debugging process at the Shanghai Synchrotron Radiation Facility(SSRF),and longitudinal instabilities were observed during the single-bunch accumulation process at Hefei Light Source(HLS).For Gaussian-distribution bunches,the uncertainty of the bunch phase obtained using this technique was better than 0.2 ps,and the bunch-length uncertainty was better than 1 ps.The dynamic range exceeded 10 ms.This technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings. 展开更多
关键词 Bunch-by-bunch diagnostic Bunch-length measurement Synchronous phase measurement Joint time–frequency-domain analysis Longitudinal instability
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A New Device for Gas-Liquid Flow Measurements Relying on Forced Annular Flow
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作者 Tiantian Yu Youping Lv +5 位作者 Hao Zhong Ming Liu Pingyuan Gai Zeju Jiang Peng Zhang Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1759-1772,共14页
A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The sw... A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The swirling blades are used to transform the complex flow pattern into a forced annular flow.Drawing on the research of existing blockage flow meters and also exploiting the single-phase flow measurement theory,a formula is introduced to measure the phase-separated flow of gas and liquid.The formula requires the pressure ratio,Lockhart-Martinelli number(L-M number),and the gas phase Froude number.The unknown parameters appearing in the formula are fitted through numerical simulation using computational fluid dynamics(CFD),which involves a comprehensive analysis of the flow field inside the device from multiple perspectives,and takes into account the influence of pressure fluctuations.Finally,the measurement model is validated through an experimental error analysis.The results demonstrate that the measurement error can be maintained within±8%for various flow patterns,including stratified flow,bubble flow,and wave flow. 展开更多
关键词 Gas-liquid flow measurement blocking flowmeter measurement model pressure fluctuations numerical simulation experimental control
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Prevention and Countermeasures of Driving Hazards
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作者 Tianchang Li 《Journal of Electronic Research and Application》 2023年第2期28-30,共3页
As a modern means of transportation,cars have made travelling much easier.However,cars also lead to many traffic accidents,which are often dangerous.Through an investigation and analysis of traffic accidents,it was fo... As a modern means of transportation,cars have made travelling much easier.However,cars also lead to many traffic accidents,which are often dangerous.Through an investigation and analysis of traffic accidents,it was found that the hidden dangers of driving are one of the main causes of car accidents.In order to better ensure the safety of driving,the hidden dangers of driving should be better prevented,traffic safety measures should be improved,and better protection should be provided for people’s lives and property.Therefore,we analyzed the hazards of driving and proposed prevention measures,in hopes of improving driving safety. 展开更多
关键词 Driving hazards prevention COUNTERmeasureS
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