In this paper, a life-cycle model with retirement is set up to study how an individual chooses the optimal retiring age on account of wage growth rate, longevity and healthy state. It is proved that there exists optim...In this paper, a life-cycle model with retirement is set up to study how an individual chooses the optimal retiring age on account of wage growth rate, longevity and healthy state. It is proved that there exists optimal retiring age under given conditions. The numerical simulations are given to show how wage growth rate, longevity and healthy state affect retiring age.展开更多
In recent years, China＇s aging population continues to accelerate the process, so that our aging population and the pension system is generated between the sustainable development of the serious contradictions, resul...In recent years, China＇s aging population continues to accelerate the process, so that our aging population and the pension system is generated between the sustainable development of the serious contradictions, resulting in a waste of human resources, increasing the operating pressure pensions, working hours inequity the negative impact on the existing retirement system challenges. Recently, the delay of the retirement age controversy sparked widespread concern in the community, the paper is as a starting point, a comprehensive analysis of the social contradictions of the current status of China＇s current retirement system, drawing on the successful adjustment of retirement abroad experience from multiple perspectives demonstrates the urgency of delayed retirement age and feasibility. This paper is divided into four chapters. The first chapter proposes the research background and significance of the age of retirement, as well as domestic and foreign scholars on the issue of research in the retirement age. The second chapter describes the status of China＇s retirement system, the contradiction between the implementation of the background, family problems and the current retirement age and the aging population about three aspects. The third chapter analyzes the feasibility to extend the retirement age. Chapter IV presents a delayed retirement policies and recommendations, with emphasis on ＂flexible retirement system.＂展开更多
With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power ...With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power batteries,especially for those high recovery value cathode materials,have not been greenly,sustainably,and efficiently recycled.Compared to the traditional recovery method for cathode materials with high energy consumption and severe secondary pollution,the direct repair regeneration,as a new type of short-process and efficient treatment methods,has attracted widespread attention.However,it still faces challenges in homogenization repair,electrochemical performance decline,and scaling-up production.To promote the direct regeneration technology development of failed NCM materials,herein we deeply discuss the failure mechanism of nickel-cobalt-manganese(NCM)ternary cathode materials,including element loss,Li/Ni mixing,phase transformation,structural defects,oxygen release,and surface degradation and reconstruction.Based on this,the detailed analysis and summary of the direct regeneration method embracing solid-phase sintering,eutectic salt assistance,solvothermal synthesis,sol-gel process,spray drying,and redox mediation are provided.Further,the upcycling strategy for regeneration materials,such as single-crystallization and high-nickelization,structural regulation,ion doping,and surface engineering,are discussed in deep.Finally,the challenges faced by the direct regeneration and corresponding countermeasures are pointed out.Undoubtedly,this review provides valuable guidance for the efficient and high-value recovery of failed cathode materials.展开更多
主题语境:志愿服务篇幅:337词建议用时:6分钟。1 Life after retirement can be isolating,especially for older men who built their identities around their jobs.Jim Isenberg,in his late 70s,experienced this first-hand.He had...主题语境:志愿服务篇幅:337词建议用时:6分钟。1 Life after retirement can be isolating,especially for older men who built their identities around their jobs.Jim Isenberg,in his late 70s,experienced this first-hand.He had a varied career in transportation and family services in White Plains,New York.When he became a grandfather,he wanted to connect with other men at the same stage of life,but found few options for grandfathers.So,he and his friend Frank Williams founded Grandpas United in 2018.展开更多
Captivated by the enduring wisdom of traditional Chinese culture and the country’s modern transformation,Patrick Nijs,former Belgian ambassador to China,chose to take root in the country after retirement and bring hi...Captivated by the enduring wisdom of traditional Chinese culture and the country’s modern transformation,Patrick Nijs,former Belgian ambassador to China,chose to take root in the country after retirement and bring his visionary green dream to life.展开更多
Helio da Silva,a retired business executive from Brazil,single⁃handedly planted over 41,000 trees in his hometown of Sao Paulo over the last two decades.Flying over the Brazilian metropolis of Sao Paulo,it's tough...Helio da Silva,a retired business executive from Brazil,single⁃handedly planted over 41,000 trees in his hometown of Sao Paulo over the last two decades.Flying over the Brazilian metropolis of Sao Paulo,it's tough to miss the 3.2-kilometer⁃long and 100⁃meter⁃wide green strip of trees wedged between two of the city's busiest roads.展开更多
The efficient recovery of silver(Ag)from retired photovoltaic(PV)panels is crucial for resource sustainability and envi-ronmental protection.This study developed an environmentally friendly leaching method using ammon...The efficient recovery of silver(Ag)from retired photovoltaic(PV)panels is crucial for resource sustainability and envi-ronmental protection.This study developed an environmentally friendly leaching method using ammonia(NH_(3)·H_(2)O)and hydrogen peroxide(H_(2)O_(2)),achieving the selective dissolution of Ag from retired crystalline silicon solar panels.Meanwhile,nonprecious metals such as aluminum(Al)and lead(Pb),which are commonly found in PV cells,were barely dissolved,dem-onstrating the excellent selectivity of this method for Ag.Light irradiation significantly improved the dissolution efficiency of Ag and reduced the amount of the reagent used.Ag dissolution occurred owing to a dual-pathway synergistic effect,which stemmed from the direct oxidation of Ag by H_(2)O_(2).The strongly oxidizing hydroxyl radicals generated by photocatalysis accelerated the oxidation and dissolution of Ag.In addition,NH 3·H_(2)O effectively promoted the dissolution and stabilization of oxidation products by forming soluble Ag–NH3·H2O complexes([Ag(NH3)2]+).This article reports an efficient,selective,and environmentally friendly strategy of Ag recovery and elucidates the radical-mediated dissolution mechanism under light-driven conditions,offering a feasible way for sustainably recovering valuable metals from retired PV panels.展开更多
Background:Depression represents a significant global mental health burden,particularly among middle-aged and older Chinese with chronic diseases in high-altitude regions,where harsh environmental conditions and limit...Background:Depression represents a significant global mental health burden,particularly among middle-aged and older Chinese with chronic diseases in high-altitude regions,where harsh environmental conditions and limited social support exacerbate mental health disparities.This paper aims to develop an interpretable machine learning prediction framework to identify the key factors of depression in this vulnerable population,thereby proposing targeted intervention measures.Methods:Utilizing data from the China Health and Retirement Longitudinal Study in 2020,this paper screened out and analyzed 2431 samples.Subsequently,Recursive Feature Elimination and Least Absolute Shrinkage and Selection Operator were applied to screen predictors from 32 alternative variables.Furthermore,through hyperparameter tuning and 5-fold cross-validation,8 machine learning modelswere constructed,namely,Random Forest,Extreme Gradient Boosting,Light Gradient Boosting Machine,Gradient Boosting Machine,K-Nearest Neighbor,Naive Bayes Classifier,Support Vector Machine,and Logistic Regression.Finally,the SHAP algorithm was applied to analyze the interpretability of the best-performing model,quantifying nonlinear relationships and threshold effects.Results:Among the respondents,the prevalence of depression was approximately 46.89%.After feature engineering screening,8 variables were retained for inclusion in the prediction model.Furthermore,the Gradient Boosting Machine performed optimally in terms of comprehensive performance,with an Area Under Receiver Operating Characteristic Curve(AUC)of 0.845,an Accuracy of 0.714,a Sensitivity of 0.655,a Precision of 0.711,a Specificity of 0.766,and an F1 of 0.682.In addition,Life satisfaction,PM2.5,Self-rated health,and Education were identified as the top 4 key factors.Meanwhile,the influence of these variables on depression showed nonlinear and threshold effects.Conclusion:This research highlights the value of machine learning in mental health.Based on the identified key factors,this paper proposed a series of policy measures to improve the health pattern of the middle-aged and elderly populations facing the dual challenges of chronic disease and environmental adversity.展开更多
The lifespan models of commercial 18650-type lithium ion batteries （nominal capacity of 1150 mA-h） were presented. The lifespan was extrapolated based on this model. The results indicate that the relationship of cap...The lifespan models of commercial 18650-type lithium ion batteries （nominal capacity of 1150 mA-h） were presented. The lifespan was extrapolated based on this model. The results indicate that the relationship of capacity retention and cycle number can be expressed by Gaussian function. The selecting function and optimal precision were verified through actual match detection and a range of alternating current impedance testing. The cycle life model with high precision （〉99%） is beneficial to shortening the orediction time and cutting the prediction cost.展开更多
This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity ...This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity and ambiguity attitude. Adopting the recursive multiple- priors utility and the technique of backward stochastic differential equations （BSDEs）, we transform the （^-maxmin expected CES utility into a classical expected CES utility under a new probability measure related to the degree of an investor＇s uncertainty. Our model investi- gates the optimal consumption-leisure-work selection, the optimal portfolio selection, and the optimal stopping problem. In this model, the investor is able to adjust her supply of labor flex- ibly above a certain minimum work-hour along with a retirement option. The problem can be analytically solved by using a variational inequality. And the optimal retirement time is given as the first time when her wealth exceeds a certain critical level. The optimal consumption-leisure and portfolio strategies before and after retirement are provided in closed forms. Finally, the distinctions of optimal consumption-leisure, portfolio and critical wealth level under ambiguity from those with no vagueness are discussed.展开更多
<p align="justify"> <span style="font-family:Verdana;">The results were analyzed by unconditional logistic regression. The analysis results showed that the positions entered into the re...<p align="justify"> <span style="font-family:Verdana;">The results were analyzed by unconditional logistic regression. The analysis results showed that the positions entered into the regression model (OR = 2.339);the expected retirement age (OR = 3.280);and delayed retirement can better solve the pension problem (OR = 0.553). Retirement can relieve child financial pressure (OR = 0.217), emotional exhaustion (OR = 0.913) and social opportunities (OR = 1.132). The OR of job title, expected retirement age, and social opportunities is greater than 1, and the others are less than 1. Conclusion: The most expected retirement age for nurses is 50 to 55 years old, and they are more inclined to retire early. Factors affecting the willingness to postpone retirement include position and expected retirement age. Postponement of retirement can better solve pension problems. Postponement of retirement can alleviate child financial pressure, social opportunities and emotional exhaustion.展开更多
Regenerating spent graphite(SG)from retired lithium-ion batteries(LIBs)can effectively avoid resource waste.However,the technology is challenged by the impurity content and energy consumption.In this study,micro-expan...Regenerating spent graphite(SG)from retired lithium-ion batteries(LIBs)can effectively avoid resource waste.However,the technology is challenged by the impurity content and energy consumption.In this study,micro-expanded graphite(MEG)was synthesized by one-step oxidation method using waste LIBs anode graphite as material and perchloric acid as intercalation and oxidant agent.Then,its performance as a LIBs anode material were investigated as well as the greenhouse gas(GHG)emissions of the whole process were calculated.Perchloric acid was successfully embedded in the SG during the reaction,which effectively removed the impurities in the graphite.Defects introduced during intercalation and delamination,such as nanopores and intercrystalline cracks.Both provide additional space for Li ions during charging and discharging,thereby promoting capacity enhancement.The prepared MEG expresses a rate capability as high as 340.32 m Ah/g at a current density of 0.1 C and still retains 81.73%of the capacity after 100 cycles at a current density of 1 C.Additionally,the GHG emissions of the synthesis process of this article and other literatures are compared.The results demonstrated that perchloric acid treatment process provides a low-carbon,time-and energy-saving approach for regenerated SG as battery grade material.展开更多
BACKGROUND As the average age of surgeons continues to rise,determining when a surgeon should retire is an important public safety concern.AIM To investigate strategies used to determine competency in the industrial w...BACKGROUND As the average age of surgeons continues to rise,determining when a surgeon should retire is an important public safety concern.AIM To investigate strategies used to determine competency in the industrial workplace that could be transferrable in the assessment of aging surgeons and to identify existing competency assessments of practicing surgeons.METHODS We searched websites describing non-medical professions within the United States where cognitive and physical competency are necessary for public safety.The mandatory age and certification process,including cognitive and physical requirements,were reported for each profession.Methods for determining surgical competency currently in use,and those existing in the literature,were also identified.RESULTS Four non-medical professions requiring mental and physical aptitude that involve public safety and have mandatory testing and/or retirement were identified:Airline pilots,air traffic controllers,firefighters,and United States State Judges.Nine late career practitioner policies designed to evaluate the ageing physician,including surgeons,were described.Six of these policies included subjective performance testing,4 using peer assessment and 2 using dexterity testing.Six objective testing methods for evaluation of surgeon technical skill were identified in the literature.All were validated for surgical trainees.Only Objective Structured Assessment of Technical Skills(OSATS)was capable of distinguishing between surgeons of different skill level and showing a relationship between skill level and post-operative outcomes.CONCLUSION A surgeon should not be forced to hang up his/her surgical cap at a predetermined age,but should be able to practice for as long as his/her surgical skills are objectively maintained at the appropriate level of competency.The strategy of using skill-based simulations in evaluating non-medical professionals can be similarly used as part of the assessment of the ageing surgeons’surgical competency,showing who may require remediation or retirement.展开更多
Based on the analysis of the tourism-based fetkement models this papet proposed five types of retirement towns, which combined the eldercare industry with ecological conditions, the style and features of ancient...Based on the analysis of the tourism-based fetkement models this papet proposed five types of retirement towns, which combined the eldercare industry with ecological conditions, the style and features of ancient towns, ttaditional cultute, die artistic envifonment, and medical cafe, and put forward relevant planning strategies from five aspects, namely, site selection, silver industry chain, functional demand, operation management mode, and safety guarantee system, providing a reference for the construction and development of domestic tourism-based retitement towns.展开更多
The Chinese government attaches great importance to the social security system, and makes it as an important pillar of socialist market economic system. Especially in the last decade, we seize the sustained, rapid and...The Chinese government attaches great importance to the social security system, and makes it as an important pillar of socialist market economic system. Especially in the last decade, we seize the sustained, rapid and healthy development of the favorable opportunity of the construction of social security system; we have made unremitting efforts and achieved important progress. After years of exploration and practice, we have a clear basic principles of the social security system and the overall objectives and major tasks, we also established social pooling and individual accounts of the basic old-age insurance, basic medical insurance system, covering pension, medical, unemployment, work injury and maternity insurance, the urban minimum living security system and the framework of the social security system basically forms. The coverage of social insurance continuously expands social security funds which are through nmltiple channels to raise the initial formation mechanism forms, the level of protection continuously improves, and management and service system also gradually improves. The social security system＇ s reform and development plays a very important role in ensuring the basic livelihood of the people, the state-owned enterprise reform, and the smooth progress of economic restructuring.展开更多
Background: Although socioeconomic support is recommended for frailtymanagement, its association with the prognosis of frailty is unclear.Methods: Using data from participants aged ≥65 years in the ChineseLongitudina...Background: Although socioeconomic support is recommended for frailtymanagement, its association with the prognosis of frailty is unclear.Methods: Using data from participants aged ≥65 years in the ChineseLongitudinal Healthy Longevity Survey (2008–2018), the associations betweensocioeconomic support (source of income, medical insurance, communitysupport, living status), onset of prefrailty/frailty, and worsening of prefrailty,were analyzed using multinominal logistic regression models. The associationsbetween self-reported low quality of life (QoL) and reversion of prefrailty/frailty were analyzed using multivariate logistic regression models. Associationswith mortality risk were analyzed using Cox proportional hazardregression models.Results: A total of 13,859 participants (mean age: 85.8 ± 11.1 years) containing2056 centenarians were included. Financial dependence was a risk factor for lowQoL among prefrail/frail individuals, but not among robust individuals. Havingcommercial or other insurance, and receiving social support from the communitywere protective factors for low QoL among prefrail/frail individuals and for theworsening of prefrailty. Continuing to work was a risk factor for low QoL, but aprotective factor for worsening of prefrailty. A negative association betweencontinuing to work and mortality existed in prefrail individuals aged <85 yearsand ≥85 years. Living alone was a risk factor for low QoL, but was notsignificantly associated with frailty prognosis.Conclusions: Prefrail and frail individuals were vulnerable to changes insocioeconomic support and more sensitive to it compared with robustindividuals. Preferential policies regarding financial support, social support,and medical insurance should be developed for individuals with frailty.展开更多
Background:Frailty in older adults is linked to increased risks and lower quality of life.Pre-frailty,a condition preceding frailty,is intervenable,but its determinants and assessment are challenging.This study aims t...Background:Frailty in older adults is linked to increased risks and lower quality of life.Pre-frailty,a condition preceding frailty,is intervenable,but its determinants and assessment are challenging.This study aims to develop and validate an explainable machine learning model for pre-frailty risk assessment among community-dwelling older adults.Methods:The study included 3141 adults aged 60 or above from the China Health and Retirement Longitudinal Study.Pre-frailty was characterized by one or two criteria from the physical frailty phenotype scale.We extracted 80 distinct features across seven dimensions to evaluate pre-frailty risk.A model was constructed using recursive feature elimination and a stacking-CatBoost distillation module on 80%of the sample and validated on a separate 20%holdout data set.Results:The study used data from 2508 community-dwelling older adults(mean age,67.24 years[range,60–96];1215[48.44%]females)to develop a pre-frailty risk assessment model.We selected 57 predictive features and built a distilled CatBoost model,which achieved the highest discrimination(AUROC:0.7560[95%CI:0.7169,0.7928])on the 20%holdout data set.The living city,BMI,and peak expiratory flow(PEF)were the three most significant contributors to pre-frailty risk.Physical and environmental factors were the top 2 impactful feature dimensions.Conclusions:An accurate and interpretable pre-frailty risk assessment framework using state-of-the-art machine learning techniques and explanation methods has been developed.Our framework incorporates a wide range of features and determinants,allowing for a comprehensive and nuanced understanding of pre-frailty risk.展开更多
Background:Every high-level athlete will eventually see his or her sport career come to an end.Most former athletes will experience changes in their self-definition and everyday behaviors as they accept a nonathletic ...Background:Every high-level athlete will eventually see his or her sport career come to an end.Most former athletes will experience changes in their self-definition and everyday behaviors as they accept a nonathletic way of life.The present study aimed to identify discrepancies between actual and former athletes regarding athletic identity,physical activity(PA),and nutrition habits.Methods:Actual athletes(AA;n=122),former athletes(FA;n=230),and nonathletes(NA;n=74)were asked to complete an online questionnaire on athletic identity,duration and intensity levels of occupational and leisure time PA,and nutritional habits.Results:FA healthy nutrition score was the lowest of the 3 groups and significantly different from that of AA.Athletic identity and intense and moderate PA during leisure time consistently decreased(p<0.01)across the 3 groups(AA>FA>NA).No significant difference between FA and NA was found regarding either nutritional habits or type of PA.Conclusion:Sport retirement may affect FA quality of nutritional habits that tends to decline below the NA level,as well as the amount of time spent practicing physical activities during leisure time.Athletic status does not ensure PA practice during sport postcareer.展开更多
This paper investigates the effects of postponing retirement on economic growth in an aging society by using the infinite overlapping generations model constructed by Blanchard (1985) in a simple endogenous growth fra...This paper investigates the effects of postponing retirement on economic growth in an aging society by using the infinite overlapping generations model constructed by Blanchard (1985) in a simple endogenous growth framework.It shows that postponing retirement may decelerate economic growth.展开更多
基金Supported by the National Natural Science Foundation of China(71271158)
文摘In this paper, a life-cycle model with retirement is set up to study how an individual chooses the optimal retiring age on account of wage growth rate, longevity and healthy state. It is proved that there exists optimal retiring age under given conditions. The numerical simulations are given to show how wage growth rate, longevity and healthy state affect retiring age.
文摘In recent years, China＇s aging population continues to accelerate the process, so that our aging population and the pension system is generated between the sustainable development of the serious contradictions, resulting in a waste of human resources, increasing the operating pressure pensions, working hours inequity the negative impact on the existing retirement system challenges. Recently, the delay of the retirement age controversy sparked widespread concern in the community, the paper is as a starting point, a comprehensive analysis of the social contradictions of the current status of China＇s current retirement system, drawing on the successful adjustment of retirement abroad experience from multiple perspectives demonstrates the urgency of delayed retirement age and feasibility. This paper is divided into four chapters. The first chapter proposes the research background and significance of the age of retirement, as well as domestic and foreign scholars on the issue of research in the retirement age. The second chapter describes the status of China＇s retirement system, the contradiction between the implementation of the background, family problems and the current retirement age and the aging population about three aspects. The third chapter analyzes the feasibility to extend the retirement age. Chapter IV presents a delayed retirement policies and recommendations, with emphasis on ＂flexible retirement system.＂
基金financially supported by the National Key Research and Development Program of China(2023YFB3809300)。
文摘With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power batteries,especially for those high recovery value cathode materials,have not been greenly,sustainably,and efficiently recycled.Compared to the traditional recovery method for cathode materials with high energy consumption and severe secondary pollution,the direct repair regeneration,as a new type of short-process and efficient treatment methods,has attracted widespread attention.However,it still faces challenges in homogenization repair,electrochemical performance decline,and scaling-up production.To promote the direct regeneration technology development of failed NCM materials,herein we deeply discuss the failure mechanism of nickel-cobalt-manganese(NCM)ternary cathode materials,including element loss,Li/Ni mixing,phase transformation,structural defects,oxygen release,and surface degradation and reconstruction.Based on this,the detailed analysis and summary of the direct regeneration method embracing solid-phase sintering,eutectic salt assistance,solvothermal synthesis,sol-gel process,spray drying,and redox mediation are provided.Further,the upcycling strategy for regeneration materials,such as single-crystallization and high-nickelization,structural regulation,ion doping,and surface engineering,are discussed in deep.Finally,the challenges faced by the direct regeneration and corresponding countermeasures are pointed out.Undoubtedly,this review provides valuable guidance for the efficient and high-value recovery of failed cathode materials.
文摘主题语境:志愿服务篇幅:337词建议用时:6分钟。1 Life after retirement can be isolating,especially for older men who built their identities around their jobs.Jim Isenberg,in his late 70s,experienced this first-hand.He had a varied career in transportation and family services in White Plains,New York.When he became a grandfather,he wanted to connect with other men at the same stage of life,but found few options for grandfathers.So,he and his friend Frank Williams founded Grandpas United in 2018.
文摘Captivated by the enduring wisdom of traditional Chinese culture and the country’s modern transformation,Patrick Nijs,former Belgian ambassador to China,chose to take root in the country after retirement and bring his visionary green dream to life.
文摘Helio da Silva,a retired business executive from Brazil,single⁃handedly planted over 41,000 trees in his hometown of Sao Paulo over the last two decades.Flying over the Brazilian metropolis of Sao Paulo,it's tough to miss the 3.2-kilometer⁃long and 100⁃meter⁃wide green strip of trees wedged between two of the city's busiest roads.
基金supported by the National Science Foundation of China(Nos.22525606,22176128,22236005,22406131,22506126)the Innovation Program of Shanghai Municipal Education Commission(No.2023ZKZD50)+13 种基金Shanghai Leading Talent Program of Eastern Talent Plan(No.LJ2023002)Shanghai Government(Nos.22dz1205400,23520711100)Chinese Education Ministry Key Laboratory and International Joint Laboratory on Resource ChemistryShanghai Eastern Scholar ProgramThe authors also thank Fellowship of China National Postdoctoral Program for Innovative Talents(No.BX20240229)the China Postdoctoral Science(No.2024M762100)the Foundation the Shanghai Science and Technology Commission Project(No.24ZR1455700)Shanghai Post-doctoral Excellence Pro-gram(No.2024787)the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Com-mission(No.24CGA49)the“111 Innovation and Talent Recruitment Base on Photochemical and Energy Materials”(No.D18020)Yunnan University Collaborative Innovation Center(Qujing Green Photovoltaic Industry Collaborative Innovation Center)Technology Talent and Platform Plan Project of Yunnan Provincial Department of Science and Technology(No.202305AF150088)Shanghai Engineering Research Center of Green Energy Chemical Engineering(No.18DZ2254200)Shanghai Frontiers Science Center of Biomimetic Catalysis.
文摘The efficient recovery of silver(Ag)from retired photovoltaic(PV)panels is crucial for resource sustainability and envi-ronmental protection.This study developed an environmentally friendly leaching method using ammonia(NH_(3)·H_(2)O)and hydrogen peroxide(H_(2)O_(2)),achieving the selective dissolution of Ag from retired crystalline silicon solar panels.Meanwhile,nonprecious metals such as aluminum(Al)and lead(Pb),which are commonly found in PV cells,were barely dissolved,dem-onstrating the excellent selectivity of this method for Ag.Light irradiation significantly improved the dissolution efficiency of Ag and reduced the amount of the reagent used.Ag dissolution occurred owing to a dual-pathway synergistic effect,which stemmed from the direct oxidation of Ag by H_(2)O_(2).The strongly oxidizing hydroxyl radicals generated by photocatalysis accelerated the oxidation and dissolution of Ag.In addition,NH 3·H_(2)O effectively promoted the dissolution and stabilization of oxidation products by forming soluble Ag–NH3·H2O complexes([Ag(NH3)2]+).This article reports an efficient,selective,and environmentally friendly strategy of Ag recovery and elucidates the radical-mediated dissolution mechanism under light-driven conditions,offering a feasible way for sustainably recovering valuable metals from retired PV panels.
基金supported by the Project of Zhongyuan Medical Innovation Foundation Hospital Management Research(25YCG1004).
文摘Background:Depression represents a significant global mental health burden,particularly among middle-aged and older Chinese with chronic diseases in high-altitude regions,where harsh environmental conditions and limited social support exacerbate mental health disparities.This paper aims to develop an interpretable machine learning prediction framework to identify the key factors of depression in this vulnerable population,thereby proposing targeted intervention measures.Methods:Utilizing data from the China Health and Retirement Longitudinal Study in 2020,this paper screened out and analyzed 2431 samples.Subsequently,Recursive Feature Elimination and Least Absolute Shrinkage and Selection Operator were applied to screen predictors from 32 alternative variables.Furthermore,through hyperparameter tuning and 5-fold cross-validation,8 machine learning modelswere constructed,namely,Random Forest,Extreme Gradient Boosting,Light Gradient Boosting Machine,Gradient Boosting Machine,K-Nearest Neighbor,Naive Bayes Classifier,Support Vector Machine,and Logistic Regression.Finally,the SHAP algorithm was applied to analyze the interpretability of the best-performing model,quantifying nonlinear relationships and threshold effects.Results:Among the respondents,the prevalence of depression was approximately 46.89%.After feature engineering screening,8 variables were retained for inclusion in the prediction model.Furthermore,the Gradient Boosting Machine performed optimally in terms of comprehensive performance,with an Area Under Receiver Operating Characteristic Curve(AUC)of 0.845,an Accuracy of 0.714,a Sensitivity of 0.655,a Precision of 0.711,a Specificity of 0.766,and an F1 of 0.682.In addition,Life satisfaction,PM2.5,Self-rated health,and Education were identified as the top 4 key factors.Meanwhile,the influence of these variables on depression showed nonlinear and threshold effects.Conclusion:This research highlights the value of machine learning in mental health.Based on the identified key factors,this paper proposed a series of policy measures to improve the health pattern of the middle-aged and elderly populations facing the dual challenges of chronic disease and environmental adversity.
基金Projects(51204209,51274240)supported by the National Natural Science Foundation of ChinaProject(HNDLKJ[2012]001-1)supported by Henan Electric Power Science&Technology Supporting Program,China
文摘The lifespan models of commercial 18650-type lithium ion batteries （nominal capacity of 1150 mA-h） were presented. The lifespan was extrapolated based on this model. The results indicate that the relationship of capacity retention and cycle number can be expressed by Gaussian function. The selecting function and optimal precision were verified through actual match detection and a range of alternating current impedance testing. The cycle life model with high precision （〉99%） is beneficial to shortening the orediction time and cutting the prediction cost.
基金Supported by National Natural Science Foundation of China (71171003, 71271003)Programming Fund Project of the Humanities and Social Sciences Research of the Ministry of Education of China (12YJA790041)+1 种基金Anhui Natural Science Foundation (090416225, 1208085MG116)Anhui Natural Science Foundation of Universities (KJ2010A037, KJ2010B026)
文摘This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity and ambiguity attitude. Adopting the recursive multiple- priors utility and the technique of backward stochastic differential equations （BSDEs）, we transform the （^-maxmin expected CES utility into a classical expected CES utility under a new probability measure related to the degree of an investor＇s uncertainty. Our model investi- gates the optimal consumption-leisure-work selection, the optimal portfolio selection, and the optimal stopping problem. In this model, the investor is able to adjust her supply of labor flex- ibly above a certain minimum work-hour along with a retirement option. The problem can be analytically solved by using a variational inequality. And the optimal retirement time is given as the first time when her wealth exceeds a certain critical level. The optimal consumption-leisure and portfolio strategies before and after retirement are provided in closed forms. Finally, the distinctions of optimal consumption-leisure, portfolio and critical wealth level under ambiguity from those with no vagueness are discussed.
文摘<p align="justify"> <span style="font-family:Verdana;">The results were analyzed by unconditional logistic regression. The analysis results showed that the positions entered into the regression model (OR = 2.339);the expected retirement age (OR = 3.280);and delayed retirement can better solve the pension problem (OR = 0.553). Retirement can relieve child financial pressure (OR = 0.217), emotional exhaustion (OR = 0.913) and social opportunities (OR = 1.132). The OR of job title, expected retirement age, and social opportunities is greater than 1, and the others are less than 1. Conclusion: The most expected retirement age for nurses is 50 to 55 years old, and they are more inclined to retire early. Factors affecting the willingness to postpone retirement include position and expected retirement age. Postponement of retirement can better solve pension problems. Postponement of retirement can alleviate child financial pressure, social opportunities and emotional exhaustion.
基金financially supported by the National Key Research and Development Program of China(No.2019YFC1907900)the National Natural Science Foundation of China(Nos.52125002 and 52100043)the National Science Foundation of Jiangxi Province(No.20202BABL213037)。
文摘Regenerating spent graphite(SG)from retired lithium-ion batteries(LIBs)can effectively avoid resource waste.However,the technology is challenged by the impurity content and energy consumption.In this study,micro-expanded graphite(MEG)was synthesized by one-step oxidation method using waste LIBs anode graphite as material and perchloric acid as intercalation and oxidant agent.Then,its performance as a LIBs anode material were investigated as well as the greenhouse gas(GHG)emissions of the whole process were calculated.Perchloric acid was successfully embedded in the SG during the reaction,which effectively removed the impurities in the graphite.Defects introduced during intercalation and delamination,such as nanopores and intercrystalline cracks.Both provide additional space for Li ions during charging and discharging,thereby promoting capacity enhancement.The prepared MEG expresses a rate capability as high as 340.32 m Ah/g at a current density of 0.1 C and still retains 81.73%of the capacity after 100 cycles at a current density of 1 C.Additionally,the GHG emissions of the synthesis process of this article and other literatures are compared.The results demonstrated that perchloric acid treatment process provides a low-carbon,time-and energy-saving approach for regenerated SG as battery grade material.
文摘BACKGROUND As the average age of surgeons continues to rise,determining when a surgeon should retire is an important public safety concern.AIM To investigate strategies used to determine competency in the industrial workplace that could be transferrable in the assessment of aging surgeons and to identify existing competency assessments of practicing surgeons.METHODS We searched websites describing non-medical professions within the United States where cognitive and physical competency are necessary for public safety.The mandatory age and certification process,including cognitive and physical requirements,were reported for each profession.Methods for determining surgical competency currently in use,and those existing in the literature,were also identified.RESULTS Four non-medical professions requiring mental and physical aptitude that involve public safety and have mandatory testing and/or retirement were identified:Airline pilots,air traffic controllers,firefighters,and United States State Judges.Nine late career practitioner policies designed to evaluate the ageing physician,including surgeons,were described.Six of these policies included subjective performance testing,4 using peer assessment and 2 using dexterity testing.Six objective testing methods for evaluation of surgeon technical skill were identified in the literature.All were validated for surgical trainees.Only Objective Structured Assessment of Technical Skills(OSATS)was capable of distinguishing between surgeons of different skill level and showing a relationship between skill level and post-operative outcomes.CONCLUSION A surgeon should not be forced to hang up his/her surgical cap at a predetermined age,but should be able to practice for as long as his/her surgical skills are objectively maintained at the appropriate level of competency.The strategy of using skill-based simulations in evaluating non-medical professionals can be similarly used as part of the assessment of the ageing surgeons’surgical competency,showing who may require remediation or retirement.
基金Sponsored by National Natural Science Fund of China(51568025)Humanities and Social Sciences Project of Colleges and Universities in Jiangxi(JC161017)
文摘Based on the analysis of the tourism-based fetkement models this papet proposed five types of retirement towns, which combined the eldercare industry with ecological conditions, the style and features of ancient towns, ttaditional cultute, die artistic envifonment, and medical cafe, and put forward relevant planning strategies from five aspects, namely, site selection, silver industry chain, functional demand, operation management mode, and safety guarantee system, providing a reference for the construction and development of domestic tourism-based retitement towns.
文摘The Chinese government attaches great importance to the social security system, and makes it as an important pillar of socialist market economic system. Especially in the last decade, we seize the sustained, rapid and healthy development of the favorable opportunity of the construction of social security system; we have made unremitting efforts and achieved important progress. After years of exploration and practice, we have a clear basic principles of the social security system and the overall objectives and major tasks, we also established social pooling and individual accounts of the basic old-age insurance, basic medical insurance system, covering pension, medical, unemployment, work injury and maternity insurance, the urban minimum living security system and the framework of the social security system basically forms. The coverage of social insurance continuously expands social security funds which are through nmltiple channels to raise the initial formation mechanism forms, the level of protection continuously improves, and management and service system also gradually improves. The social security system＇ s reform and development plays a very important role in ensuring the basic livelihood of the people, the state-owned enterprise reform, and the smooth progress of economic restructuring.
文摘Background: Although socioeconomic support is recommended for frailtymanagement, its association with the prognosis of frailty is unclear.Methods: Using data from participants aged ≥65 years in the ChineseLongitudinal Healthy Longevity Survey (2008–2018), the associations betweensocioeconomic support (source of income, medical insurance, communitysupport, living status), onset of prefrailty/frailty, and worsening of prefrailty,were analyzed using multinominal logistic regression models. The associationsbetween self-reported low quality of life (QoL) and reversion of prefrailty/frailty were analyzed using multivariate logistic regression models. Associationswith mortality risk were analyzed using Cox proportional hazardregression models.Results: A total of 13,859 participants (mean age: 85.8 ± 11.1 years) containing2056 centenarians were included. Financial dependence was a risk factor for lowQoL among prefrail/frail individuals, but not among robust individuals. Havingcommercial or other insurance, and receiving social support from the communitywere protective factors for low QoL among prefrail/frail individuals and for theworsening of prefrailty. Continuing to work was a risk factor for low QoL, but aprotective factor for worsening of prefrailty. A negative association betweencontinuing to work and mortality existed in prefrail individuals aged <85 yearsand ≥85 years. Living alone was a risk factor for low QoL, but was notsignificantly associated with frailty prognosis.Conclusions: Prefrail and frail individuals were vulnerable to changes insocioeconomic support and more sensitive to it compared with robustindividuals. Preferential policies regarding financial support, social support,and medical insurance should be developed for individuals with frailty.
文摘Background:Frailty in older adults is linked to increased risks and lower quality of life.Pre-frailty,a condition preceding frailty,is intervenable,but its determinants and assessment are challenging.This study aims to develop and validate an explainable machine learning model for pre-frailty risk assessment among community-dwelling older adults.Methods:The study included 3141 adults aged 60 or above from the China Health and Retirement Longitudinal Study.Pre-frailty was characterized by one or two criteria from the physical frailty phenotype scale.We extracted 80 distinct features across seven dimensions to evaluate pre-frailty risk.A model was constructed using recursive feature elimination and a stacking-CatBoost distillation module on 80%of the sample and validated on a separate 20%holdout data set.Results:The study used data from 2508 community-dwelling older adults(mean age,67.24 years[range,60–96];1215[48.44%]females)to develop a pre-frailty risk assessment model.We selected 57 predictive features and built a distilled CatBoost model,which achieved the highest discrimination(AUROC:0.7560[95%CI:0.7169,0.7928])on the 20%holdout data set.The living city,BMI,and peak expiratory flow(PEF)were the three most significant contributors to pre-frailty risk.Physical and environmental factors were the top 2 impactful feature dimensions.Conclusions:An accurate and interpretable pre-frailty risk assessment framework using state-of-the-art machine learning techniques and explanation methods has been developed.Our framework incorporates a wide range of features and determinants,allowing for a comprehensive and nuanced understanding of pre-frailty risk.
文摘Background:Every high-level athlete will eventually see his or her sport career come to an end.Most former athletes will experience changes in their self-definition and everyday behaviors as they accept a nonathletic way of life.The present study aimed to identify discrepancies between actual and former athletes regarding athletic identity,physical activity(PA),and nutrition habits.Methods:Actual athletes(AA;n=122),former athletes(FA;n=230),and nonathletes(NA;n=74)were asked to complete an online questionnaire on athletic identity,duration and intensity levels of occupational and leisure time PA,and nutritional habits.Results:FA healthy nutrition score was the lowest of the 3 groups and significantly different from that of AA.Athletic identity and intense and moderate PA during leisure time consistently decreased(p<0.01)across the 3 groups(AA>FA>NA).No significant difference between FA and NA was found regarding either nutritional habits or type of PA.Conclusion:Sport retirement may affect FA quality of nutritional habits that tends to decline below the NA level,as well as the amount of time spent practicing physical activities during leisure time.Athletic status does not ensure PA practice during sport postcareer.
文摘This paper investigates the effects of postponing retirement on economic growth in an aging society by using the infinite overlapping generations model constructed by Blanchard (1985) in a simple endogenous growth framework.It shows that postponing retirement may decelerate economic growth.
