Dependent competing risks model is a practical model in the analysis of lifetime and failure modes.The dependence can be captured using a statistical tool to explore the re-lationship among failure causes.In this pape...Dependent competing risks model is a practical model in the analysis of lifetime and failure modes.The dependence can be captured using a statistical tool to explore the re-lationship among failure causes.In this paper,an Archimedean copula is chosen to describe the dependence in a constant-stress accelerated life test.We study the Archimedean copula based dependent competing risks model using parametric and nonparametric methods.The parametric likelihood inference is presented by deriving the general expression of likelihood function based on assumed survival Archimedean copula associated with the model parameter estimation.Combining the nonparametric estimation with progressive censoring and the non-parametric copula estimation,we introduce a nonparametric reliability estimation method given competing risks data.A simulation study and a real data analysis are conducted to show the performance of the estimation methods.展开更多
This paper explores the reform and practice of software engineering-related courses based on the competency model of the Computing Curricula,and proposes some measures of teaching reform and talent cultivation in soft...This paper explores the reform and practice of software engineering-related courses based on the competency model of the Computing Curricula,and proposes some measures of teaching reform and talent cultivation in software engineering.The teaching reform emphasizes student-centered education,and focuses on the cultivation and enhancement of students’knowledge,skills,and dispositions.Based on the three elements of the competency model,specific measures of teaching reform are proposed for some professional courses in software engineering,to strengthen course relevance,improve knowledge systems,reform practical modes with a focus on skill development,and cultivate good dispositions through student-centered education.The teaching reform’s attempts and practice are conducted in some courses such as Advanced Web Technologies,Software Engineering,and Intelligent Terminal Systems and Application Development.Through the analysis and comparison of the implementation effects,significant improvements are observed in teaching effectiveness,students’mastery of knowledge and skills are noticeably improved,and the expected goals of the teaching reform are achieved.展开更多
Background:This study uses a literature review and the Delphi expert consultation method to construct a competency evaluation model for infection control personnel in traditional Chinese medicine(TCM)hospitals.The aim...Background:This study uses a literature review and the Delphi expert consultation method to construct a competency evaluation model for infection control personnel in traditional Chinese medicine(TCM)hospitals.The aim is to strengthen infection control management in TCM hospitals,assess the competency of infection control personnel in their positions,and assist them in identifying the competencies that need improvement.Methods:Based on the literature research method and the Delphi expert consultation method,a competency model for the position was constructed through two rounds of expert consultations,analyzing the relationships between various factors and establishing a hierarchical structure model.Pairwise comparisons were made among the elements at the same level to construct a judgment matrix.Through the analytic hierarchy process,the weight coefficients of the indicators at each level in the competency model were obtained.Results:This study conducted a comprehensive assessment of various capabilities and practices related to hospital infection control.The survey results indicate that participants excelled in multiple areas,with a high overall satisfaction rate.95.28%of participants were able to develop hospital infection monitoring plans based on national infection control policies,demonstrating a good understanding and execution of these policies.94.09%of participants were familiar with high-risk populations and key departments in the hospital.91.73%of participants were able to establish monitoring scopes based on the trends of multidrug-resistant bacteria and conduct information monitoring,reflecting strong response capabilities.92.91%of participants were able to collaborate with relevant departments to conduct bacterial resistance monitoring,showing a good team spirit.94.49%of participants were able to perform targeted monitoring,including surgical site infections,indicating that they have effective monitoring strategies.91.34%of participants were able to collect and organize monitoring data and establish a systematic database,demonstrating good data management skills.90.16%of participants were able to interpret laws and regulations related to hospital infection management,indicating a high level of legal knowledge.89.37%of participants generally possessed good communication skills.92.52%of participants were able to guide medical staff on occupational safety and protective knowledge,showing an emphasis on occupational health.Participants demonstrated a strong desire to learn and innovate,with 87.01%actively participating in continuing education and research activities,reflecting a pursuit of professional development.Conclusion:Based on the results of the two rounds of expert consultations,a competency evaluation model for infection control personnel in TCM hospitals was formed.Through the analytic hierarchy process,the weight coefficients of various indicators at different levels in the model were obtained,and the research results have good scientific validity and reliability.展开更多
The competency model is a widely-used human resource management tool that can be applied to human resource management in different regions,different fields,different enterprises,and positions of different nature,which...The competency model is a widely-used human resource management tool that can be applied to human resource management in different regions,different fields,different enterprises,and positions of different nature,which can improve the objectivity,reliability,authenticity and fairness of enterprise human resource management,give full play to the promotion of human resource management to the development of enterprise operations,and help enterprises achieve development and manage-ment goals.展开更多
In this paper, we conduct in-depth research on the human resource management mode based on competency model. Treatment of competency is defined based on the previous scholars, this paper defines enterprise top managem...In this paper, we conduct in-depth research on the human resource management mode based on competency model. Treatment of competency is defined based on the previous scholars, this paper defines enterprise top management competency as can change the performance is outstanding person in senior management positions in companies and generally do distinguish individual potential. Corporate culture has a strong and lasting soft binding, plays an important role in modem enterprise management. The numerical analysis supports the effectiveness and feasibility of the model. In the future, we will conduct more related work to optimize the current theory.展开更多
This paper reports a five-year computer-mediated intercultural exchange project between Chinese and American university students that explores the use of various social media tools with WeChat application as the main ...This paper reports a five-year computer-mediated intercultural exchange project between Chinese and American university students that explores the use of various social media tools with WeChat application as the main medium in collaborative intercultural assignments. The study combines quantitative and qualitative approaches by using questionnaires and action research, to investigate how Chinese EFL and American CFL learners increase their intercultural communication competence by assessing their knowledge, awareness, attitudes, and skills of discovery and awareness. The findings reveal their changes and progress in the following variables: knowledge about the variety and subtlety of both the home and target cultures, a different worldview, and cultural study methods;awareness of the importance of differences and similarities between the home and target cultures, their negative reactions to these differences(e.g., fear, ridicule, disgust, feeling of superiority, etc.) and therefore, critical evaluation of the target and home cultures;attitudes from excitement or blind admiration of the target culture to confusion, anxiety or frustration about the cultural differences, later to toleration and appreciation of cultural differences, adaptation to the target culture, and eventually to openness and readiness to suspend disbelief about other cultures and belief about one’s own;skills to contrast the target culture with their own, to demonstrate a capacity to interact appropriately in a variety of different social situations in the target culture and resolve cross-cultural conflicts and misunderstandings. This research will serve as a valuable reference for computer-mediated intercultural communication teaching and open up new possibilities to extend classroom teaching by bridging the gap between second-hand knowledge and hands-on experience.展开更多
Objective:To explore the effectiveness of the competency model for nursing managers in the training of newly appointed head nurses.Methods:Eighteen newly appointed head nurses from Yichang Central People’s Hospital,s...Objective:To explore the effectiveness of the competency model for nursing managers in the training of newly appointed head nurses.Methods:Eighteen newly appointed head nurses from Yichang Central People’s Hospital,selected between August 2023 and July 2024,were chosen as the research subjects.Based on the nursing manager competency model,corresponding training programs were developed,and these 18 head nurses were trained accordingly.Results:After the training,all newly appointed head nurses passed the theoretical assessments,with a pass rate of 100.00%.The pass rates for two rounds of assessment were 100.00%and 94.54%,respectively.There was no significant difference in the performance evaluation scores between new and senior head nurses in terms of standardized services,nursing quality,nursing research and teaching,and patient satisfaction(P>0.05).Conclusion:The competency model for nursing managers has a significant effect on the training of newly appointed head nurses.It effectively enhances management awareness,facilitates role transition,and,to some extent,improves the management and leadership capabilities of head nurses.It holds high value for broader implementation.展开更多
Enterprises are continuously aiming at improving the execution of processes to achieve a competitive edge.One of the established ways of improving process performance is to assign the most appropriate resources to eac...Enterprises are continuously aiming at improving the execution of processes to achieve a competitive edge.One of the established ways of improving process performance is to assign the most appropriate resources to each task of the process.However,evaluations of business process improvement approaches have established that a method that can guide decision-makers to identify the most appropriate resources for a task of process improvement in a structured way,is missing.It is because the relationship between resources and tasks is less understood and advancement in business process intelligence is also ignored.To address this problem an integrated resource classification framework is presenting that identifies competence,suitability,and preference as the relationship of task with resources.But,only the competence relationship of human resources with a task is presented in this research as a resource competence model.Furthermore,the competency calculation method is presented as a user guider layer for business process intelligencebased resource competence evaluation.The computed capabilities serve as a basic input for choosing the most appropriate resources for each task of the process.Applicability of method is illustrated through a heathcare case study.展开更多
The presented paper analyses competencies of project manager of the enterprises operating on Czech lottery market. The contribution of the paper consists of two parts. The first part focuses on the basic terminology i...The presented paper analyses competencies of project manager of the enterprises operating on Czech lottery market. The contribution of the paper consists of two parts. The first part focuses on the basic terminology issues and anchors concepts such as project manager and competencies. The second part is dedicated to the analyzing and evaluation of the competencies of ideal project manager of the enterprises operating on Czech lottery market and subsequent presentation and verification. For the analyzing and evaluation of the competencies of ideal project manager, the questionnaire of the scale type with the grade valuation 1-6 was applied within the frame of 20 enterprises operating on the lottery market in Czech Republic. The respondents were from the AG CZ, Ltd. and the competitors of this enterprise. Analyzed data were after the evaluation worked up into the form of graphs. The final output of this paper is the definition of the competencies of ideal project manager operating on Czech lottery market. The paper arose thanks to the project supportted by The Ministry of Education, Slovakia （Project KEGA No. 001DTI-4/2015, proposal of behavior strategies in the difficult social situations in the management of secondary school using the innovative predictive software tools） in cooperation of Dubnicky, Technological lnstitut in Dubnica nad Vahom with AG CZ, Ltd. and The Institute of Technological and Business in Ceske Budejovice.展开更多
The shortage of individuals with the abilities to perform a job position successfully demands innovative educational approaches. Competency Based Education (CBE) is a methodology that focuses on endowing students with...The shortage of individuals with the abilities to perform a job position successfully demands innovative educational approaches. Competency Based Education (CBE) is a methodology that focuses on endowing students with the skills demanded by the in-dustries and evaluates them regarding what they are able to do. A bank of competen-cies that students must acquire in a university academic program was discussed. Occupational trends as well as associated skills demands were detected. This research could be a source of practical knowledge for those organizations seeking to understand CBE foundations and for those wishing to initiate their path through this global educational trend.展开更多
The article is to introduce author's research results in recent years in the field of leadership behavior. The main researches conducted in this field include competency model of senior executives in communication...The article is to introduce author's research results in recent years in the field of leadership behavior. The main researches conducted in this field include competency model of senior executives in communication industry and family firms; transformational leadership and its relationship with leadership effectiveness, the impact of supervisor's feedback on employees' behavior and the cross-culture study of supervisor's feedback. Theoretical and practical contributions of these researches are explained. Directions for future research are discussed.展开更多
Based on the competency model building theory, a literature review, a behavioral event interview and statistical analysis were used in this study to build a competency model for pharmacists in China. The competency mo...Based on the competency model building theory, a literature review, a behavioral event interview and statistical analysis were used in this study to build a competency model for pharmacists in China. The competency model framework for pharmacists included five dimensions of characteristics, consisting of 25 competency elements of pharmacists, such as the general competency elements that all pharmacists should possess and outstanding competency elements that community pharmacists and hospital pharmacists should possess. This newly constructed competency model for pharmacists helped develop and cultivate the abilities of future Chinese pharmacists.展开更多
The existence and stability of periodic solution of competing reaction-diffusion models with grazing rates in population dynamics are discussed in this paper, the sufficient conditions are obtained for existence of a ...The existence and stability of periodic solution of competing reaction-diffusion models with grazing rates in population dynamics are discussed in this paper, the sufficient conditions are obtained for existence of a globally asymptotically stable strictly positive spatial homogeneity periodic solution by methods of comparison theory Brouwer’s fixed point theorem and Liapunov function.展开更多
Unraveling the nature of complex condensed matter systems is of paramount importance in a variety of fields such as pharmacology and materials science.Here we report the synthesis,by the dynamic covalent chemistry(DCC...Unraveling the nature of complex condensed matter systems is of paramount importance in a variety of fields such as pharmacology and materials science.Here we report the synthesis,by the dynamic covalent chemistry(DCC),of a robust,continuous,and low-defect glassy covalent organic network(GCON).The direct imaging of the molecular structure clearly shows the amorphous nature of GCONs,which consists with the competing(nano)crystallite model,not Zachariasen continuous random networks(Z-CRN).Remarkably,the microscopic friction properties were measured on GCONs by atomic force microscopy(AFM),and the GCONs showed lower friction force in comparison with crystalline covalent organic frameworks(COFs).展开更多
There has been lack of studies that investigate the causal impact of alcohol consumption on health and mortality in middle-aged and older populations in China.This cohort study aims to investigate whether alcohol use ...There has been lack of studies that investigate the causal impact of alcohol consumption on health and mortality in middle-aged and older populations in China.This cohort study aims to investigate whether alcohol use increases poor health and mortality risk in middle-aged and older Chinese population.The study is a cohort study design that was based on the China Health and Retired Longitudinal study(CHARLS).Measures of poor health and alcohol use are self-rated poor/very poor and alcohol use.Competing Cox proportional hazard regression model(CPHM)was used to model the data and the hazards ratio(HR)of poor health,mortality for current and former drinkers versus nondrinkers and current drinkers versus former drinkers was estimated using CPHM after adjusting for deign-effects and covariates.This study found significantly increased risk of all-cause mortality among current(adjusted HR=1.54 and P=0.0423)and former drinkers(Adjusted HR=1.52 and P=0.0096)compared to lifetime nondrinkers among middle-aged and senior Chinese people;significantly increased hazard of poor health among current drinkers(Adjusted HR=1.26 and P=0.0443)compared with lifetime nondrinkers.The hazards of all-cause mortality and self-rated poor health increased with the amount and frequency of alcohol drinking,and drinking years.This study found that either former or current drinkers self-rated having a poor health and had a significantly increased risk of all-cause mortality compared with nondrinkers.Heavy drinkers had poor health status and higher risk of mortality compared with those who drank light or moderate amount of alcohol in middle-aged and senior Chinese population.展开更多
基金Supported by the National Natural Science Foundation of China(12101476,12061091,11901134)the Fundamental Research Funds for the Central Universities(ZYTS23054,QTZX22054)+1 种基金the Yunnan Funda-mental Research Projects(202101AT070103)the Natural Science Basic Research Program of Shaanxi Province(2020JQ-285).
文摘Dependent competing risks model is a practical model in the analysis of lifetime and failure modes.The dependence can be captured using a statistical tool to explore the re-lationship among failure causes.In this paper,an Archimedean copula is chosen to describe the dependence in a constant-stress accelerated life test.We study the Archimedean copula based dependent competing risks model using parametric and nonparametric methods.The parametric likelihood inference is presented by deriving the general expression of likelihood function based on assumed survival Archimedean copula associated with the model parameter estimation.Combining the nonparametric estimation with progressive censoring and the non-parametric copula estimation,we introduce a nonparametric reliability estimation method given competing risks data.A simulation study and a real data analysis are conducted to show the performance of the estimation methods.
基金supported by the Teaching Reform Projects of Colleges in Hunan Province(No.HNJG-2022-1410,No.HNJG-2020-0489,No.HNJG-2022-0785,and No.HNJG-2022-0792)Industry-universityCooperative Project of Ministry of Education(No.220506194233806)the Teaching Reform Project of Hunan University of Science and Technology(No.2020XXJG07)。
文摘This paper explores the reform and practice of software engineering-related courses based on the competency model of the Computing Curricula,and proposes some measures of teaching reform and talent cultivation in software engineering.The teaching reform emphasizes student-centered education,and focuses on the cultivation and enhancement of students’knowledge,skills,and dispositions.Based on the three elements of the competency model,specific measures of teaching reform are proposed for some professional courses in software engineering,to strengthen course relevance,improve knowledge systems,reform practical modes with a focus on skill development,and cultivate good dispositions through student-centered education.The teaching reform’s attempts and practice are conducted in some courses such as Advanced Web Technologies,Software Engineering,and Intelligent Terminal Systems and Application Development.Through the analysis and comparison of the implementation effects,significant improvements are observed in teaching effectiveness,students’mastery of knowledge and skills are noticeably improved,and the expected goals of the teaching reform are achieved.
基金supported by Weifang Science and Technology Development Plan Project(Soft Science,2022RKX054)Shenzhen Elite Talent Project(JY2024-2).
文摘Background:This study uses a literature review and the Delphi expert consultation method to construct a competency evaluation model for infection control personnel in traditional Chinese medicine(TCM)hospitals.The aim is to strengthen infection control management in TCM hospitals,assess the competency of infection control personnel in their positions,and assist them in identifying the competencies that need improvement.Methods:Based on the literature research method and the Delphi expert consultation method,a competency model for the position was constructed through two rounds of expert consultations,analyzing the relationships between various factors and establishing a hierarchical structure model.Pairwise comparisons were made among the elements at the same level to construct a judgment matrix.Through the analytic hierarchy process,the weight coefficients of the indicators at each level in the competency model were obtained.Results:This study conducted a comprehensive assessment of various capabilities and practices related to hospital infection control.The survey results indicate that participants excelled in multiple areas,with a high overall satisfaction rate.95.28%of participants were able to develop hospital infection monitoring plans based on national infection control policies,demonstrating a good understanding and execution of these policies.94.09%of participants were familiar with high-risk populations and key departments in the hospital.91.73%of participants were able to establish monitoring scopes based on the trends of multidrug-resistant bacteria and conduct information monitoring,reflecting strong response capabilities.92.91%of participants were able to collaborate with relevant departments to conduct bacterial resistance monitoring,showing a good team spirit.94.49%of participants were able to perform targeted monitoring,including surgical site infections,indicating that they have effective monitoring strategies.91.34%of participants were able to collect and organize monitoring data and establish a systematic database,demonstrating good data management skills.90.16%of participants were able to interpret laws and regulations related to hospital infection management,indicating a high level of legal knowledge.89.37%of participants generally possessed good communication skills.92.52%of participants were able to guide medical staff on occupational safety and protective knowledge,showing an emphasis on occupational health.Participants demonstrated a strong desire to learn and innovate,with 87.01%actively participating in continuing education and research activities,reflecting a pursuit of professional development.Conclusion:Based on the results of the two rounds of expert consultations,a competency evaluation model for infection control personnel in TCM hospitals was formed.Through the analytic hierarchy process,the weight coefficients of various indicators at different levels in the model were obtained,and the research results have good scientific validity and reliability.
文摘The competency model is a widely-used human resource management tool that can be applied to human resource management in different regions,different fields,different enterprises,and positions of different nature,which can improve the objectivity,reliability,authenticity and fairness of enterprise human resource management,give full play to the promotion of human resource management to the development of enterprise operations,and help enterprises achieve development and manage-ment goals.
文摘In this paper, we conduct in-depth research on the human resource management mode based on competency model. Treatment of competency is defined based on the previous scholars, this paper defines enterprise top management competency as can change the performance is outstanding person in senior management positions in companies and generally do distinguish individual potential. Corporate culture has a strong and lasting soft binding, plays an important role in modem enterprise management. The numerical analysis supports the effectiveness and feasibility of the model. In the future, we will conduct more related work to optimize the current theory.
文摘This paper reports a five-year computer-mediated intercultural exchange project between Chinese and American university students that explores the use of various social media tools with WeChat application as the main medium in collaborative intercultural assignments. The study combines quantitative and qualitative approaches by using questionnaires and action research, to investigate how Chinese EFL and American CFL learners increase their intercultural communication competence by assessing their knowledge, awareness, attitudes, and skills of discovery and awareness. The findings reveal their changes and progress in the following variables: knowledge about the variety and subtlety of both the home and target cultures, a different worldview, and cultural study methods;awareness of the importance of differences and similarities between the home and target cultures, their negative reactions to these differences(e.g., fear, ridicule, disgust, feeling of superiority, etc.) and therefore, critical evaluation of the target and home cultures;attitudes from excitement or blind admiration of the target culture to confusion, anxiety or frustration about the cultural differences, later to toleration and appreciation of cultural differences, adaptation to the target culture, and eventually to openness and readiness to suspend disbelief about other cultures and belief about one’s own;skills to contrast the target culture with their own, to demonstrate a capacity to interact appropriately in a variety of different social situations in the target culture and resolve cross-cultural conflicts and misunderstandings. This research will serve as a valuable reference for computer-mediated intercultural communication teaching and open up new possibilities to extend classroom teaching by bridging the gap between second-hand knowledge and hands-on experience.
文摘Objective:To explore the effectiveness of the competency model for nursing managers in the training of newly appointed head nurses.Methods:Eighteen newly appointed head nurses from Yichang Central People’s Hospital,selected between August 2023 and July 2024,were chosen as the research subjects.Based on the nursing manager competency model,corresponding training programs were developed,and these 18 head nurses were trained accordingly.Results:After the training,all newly appointed head nurses passed the theoretical assessments,with a pass rate of 100.00%.The pass rates for two rounds of assessment were 100.00%and 94.54%,respectively.There was no significant difference in the performance evaluation scores between new and senior head nurses in terms of standardized services,nursing quality,nursing research and teaching,and patient satisfaction(P>0.05).Conclusion:The competency model for nursing managers has a significant effect on the training of newly appointed head nurses.It effectively enhances management awareness,facilitates role transition,and,to some extent,improves the management and leadership capabilities of head nurses.It holds high value for broader implementation.
文摘Enterprises are continuously aiming at improving the execution of processes to achieve a competitive edge.One of the established ways of improving process performance is to assign the most appropriate resources to each task of the process.However,evaluations of business process improvement approaches have established that a method that can guide decision-makers to identify the most appropriate resources for a task of process improvement in a structured way,is missing.It is because the relationship between resources and tasks is less understood and advancement in business process intelligence is also ignored.To address this problem an integrated resource classification framework is presenting that identifies competence,suitability,and preference as the relationship of task with resources.But,only the competence relationship of human resources with a task is presented in this research as a resource competence model.Furthermore,the competency calculation method is presented as a user guider layer for business process intelligencebased resource competence evaluation.The computed capabilities serve as a basic input for choosing the most appropriate resources for each task of the process.Applicability of method is illustrated through a heathcare case study.
文摘The presented paper analyses competencies of project manager of the enterprises operating on Czech lottery market. The contribution of the paper consists of two parts. The first part focuses on the basic terminology issues and anchors concepts such as project manager and competencies. The second part is dedicated to the analyzing and evaluation of the competencies of ideal project manager of the enterprises operating on Czech lottery market and subsequent presentation and verification. For the analyzing and evaluation of the competencies of ideal project manager, the questionnaire of the scale type with the grade valuation 1-6 was applied within the frame of 20 enterprises operating on the lottery market in Czech Republic. The respondents were from the AG CZ, Ltd. and the competitors of this enterprise. Analyzed data were after the evaluation worked up into the form of graphs. The final output of this paper is the definition of the competencies of ideal project manager operating on Czech lottery market. The paper arose thanks to the project supportted by The Ministry of Education, Slovakia （Project KEGA No. 001DTI-4/2015, proposal of behavior strategies in the difficult social situations in the management of secondary school using the innovative predictive software tools） in cooperation of Dubnicky, Technological lnstitut in Dubnica nad Vahom with AG CZ, Ltd. and The Institute of Technological and Business in Ceske Budejovice.
文摘The shortage of individuals with the abilities to perform a job position successfully demands innovative educational approaches. Competency Based Education (CBE) is a methodology that focuses on endowing students with the skills demanded by the in-dustries and evaluates them regarding what they are able to do. A bank of competen-cies that students must acquire in a university academic program was discussed. Occupational trends as well as associated skills demands were detected. This research could be a source of practical knowledge for those organizations seeking to understand CBE foundations and for those wishing to initiate their path through this global educational trend.
基金Supported by the Social Science Base Momentous Program, Ministry of Education (No. 02JAZJD630002)
文摘The article is to introduce author's research results in recent years in the field of leadership behavior. The main researches conducted in this field include competency model of senior executives in communication industry and family firms; transformational leadership and its relationship with leadership effectiveness, the impact of supervisor's feedback on employees' behavior and the cross-culture study of supervisor's feedback. Theoretical and practical contributions of these researches are explained. Directions for future research are discussed.
文摘Based on the competency model building theory, a literature review, a behavioral event interview and statistical analysis were used in this study to build a competency model for pharmacists in China. The competency model framework for pharmacists included five dimensions of characteristics, consisting of 25 competency elements of pharmacists, such as the general competency elements that all pharmacists should possess and outstanding competency elements that community pharmacists and hospital pharmacists should possess. This newly constructed competency model for pharmacists helped develop and cultivate the abilities of future Chinese pharmacists.
文摘The existence and stability of periodic solution of competing reaction-diffusion models with grazing rates in population dynamics are discussed in this paper, the sufficient conditions are obtained for existence of a globally asymptotically stable strictly positive spatial homogeneity periodic solution by methods of comparison theory Brouwer’s fixed point theorem and Liapunov function.
基金This work was financially supported by the National Science Foundation of China(Nos.52073208,21872103,and 51633006)the Ministry of Science and Technology of China(No 2016YFB0401100).
文摘Unraveling the nature of complex condensed matter systems is of paramount importance in a variety of fields such as pharmacology and materials science.Here we report the synthesis,by the dynamic covalent chemistry(DCC),of a robust,continuous,and low-defect glassy covalent organic network(GCON).The direct imaging of the molecular structure clearly shows the amorphous nature of GCONs,which consists with the competing(nano)crystallite model,not Zachariasen continuous random networks(Z-CRN).Remarkably,the microscopic friction properties were measured on GCONs by atomic force microscopy(AFM),and the GCONs showed lower friction force in comparison with crystalline covalent organic frameworks(COFs).
基金funded by the National Institute on Ageing(R01 AG030153,RC2 AG036619,R03 AG043052).
文摘There has been lack of studies that investigate the causal impact of alcohol consumption on health and mortality in middle-aged and older populations in China.This cohort study aims to investigate whether alcohol use increases poor health and mortality risk in middle-aged and older Chinese population.The study is a cohort study design that was based on the China Health and Retired Longitudinal study(CHARLS).Measures of poor health and alcohol use are self-rated poor/very poor and alcohol use.Competing Cox proportional hazard regression model(CPHM)was used to model the data and the hazards ratio(HR)of poor health,mortality for current and former drinkers versus nondrinkers and current drinkers versus former drinkers was estimated using CPHM after adjusting for deign-effects and covariates.This study found significantly increased risk of all-cause mortality among current(adjusted HR=1.54 and P=0.0423)and former drinkers(Adjusted HR=1.52 and P=0.0096)compared to lifetime nondrinkers among middle-aged and senior Chinese people;significantly increased hazard of poor health among current drinkers(Adjusted HR=1.26 and P=0.0443)compared with lifetime nondrinkers.The hazards of all-cause mortality and self-rated poor health increased with the amount and frequency of alcohol drinking,and drinking years.This study found that either former or current drinkers self-rated having a poor health and had a significantly increased risk of all-cause mortality compared with nondrinkers.Heavy drinkers had poor health status and higher risk of mortality compared with those who drank light or moderate amount of alcohol in middle-aged and senior Chinese population.
