We propose a computing model in which individuals can automatically adjust their interaction intensity with their mentor according to the learning effect.This model is designed to investigate the cooperative dynamics ...We propose a computing model in which individuals can automatically adjust their interaction intensity with their mentor according to the learning effect.This model is designed to investigate the cooperative dynamics of the spatial prisoner's dilemma.More specifically,when the cumulative payoff of a learner is more than his reference earning,he will strengthen his interaction with his mentor;otherwise,he will reduce it.The experimental results indicate that this mechanism can improve the emergence of cooperation in a networked population and that the driving coefficient of interaction intensity plays an important role in promoting cooperation.Interestingly,under a certain social dilemma condition,there exists a minimal driving coefficient that leads to optimal cooperation.This occurs due to a positive feedback effect between the individual's satisfaction frequency and the number of effective neighbors.Moreover,we find that the experimental results are in accord with theoretical predictions obtained from an extension of the classical pair-approximation method.Our conclusions obtained by considering relationships with mentors can provide a new perspective for future investigations into the dynamics of evolutionary games within structured populations.展开更多
Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival...Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival and spiritual dilemma of Indian women in the transformation of India’s modernization.The novel depicts in both content and form the plight of Indian women’s physical and spiritual dependence under the traditional concepts of arranged marriages,caste marriages,dowry system and patriarchal will,and shows the process of women’s body and self-consciousness gradually moving from vitality to extinction.展开更多
The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, cha...The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, characterized by independence and specialization, is designed to mitigate these shortcomings. However, the implementation of third-party assessment faces challenges too. This paper intends to improve the third-party assessment system and to realize the legislative purpose of the system. Based on social research, discussions and exchanges with relevant parties, and the existing research results, this paper analyzes the challenges and possible optimization measures for the third-party assessment. The challenges include repulsion from policy-making bodies, insufficient independence of assessment bodies, disparity of assessment quality, and limited application of assessment outcomes. Possible optimization measures include promoting fair competition culture, increasing the acceptance of third-party assessment from policy-making bodies, enhancing the quality of third-party assessment, clarifying the relationship between policy-making bodies and assessment bodies, ensuring the independence of third-party assessments, and promoting the application of assessment results.展开更多
This paper comprehensively analyzes the development opportunities and realistic dilemmas faced by adult higher education in China in the new era,and puts forward corresponding strategies as solutions.With the construc...This paper comprehensively analyzes the development opportunities and realistic dilemmas faced by adult higher education in China in the new era,and puts forward corresponding strategies as solutions.With the construction of a learning society,the development of digital technology,and the popularization of the concept of lifelong learning,adult higher education has unprecedented development opportunities.At the same time,these forms of education are facing a series of dilemmas due to challenges such as unsound guarantee mechanisms and traditional enrollment competition.Through the establishment of perfect legal and policy guarantees,transformation of school running mode,meeting the diversified needs of learners,and other multi-faceted measures,the development of adult higher education can be effectively promoted to meet the needs of individual and social development.展开更多
Blended teaching has emerged as a prominent subject in the recent reform and innovation of higher education.It has become imperative and guiding for colleges and universities to embrace a mixed teaching approach that ...Blended teaching has emerged as a prominent subject in the recent reform and innovation of higher education.It has become imperative and guiding for colleges and universities to embrace a mixed teaching approach that aligns with the evolving needs of education and teaching in the new era.This paper aims to provide a comprehensive overview of the research status surrounding blended teaching,encompassing fundamental issues,teaching design,practical guidance,teaching effectiveness,and evaluation.By critically examining the current challenges associated with blended teaching,this study proposes optimization strategies including enhancing student participation and interaction,promoting deep learning,improving teachers’preparedness,teaching technologies,and curriculum design capabilities,strengthening top-level design,and perfecting evaluation and incentive mechanisms.These strategies provide new directions for the reform of blended teaching.展开更多
Cultivating students'higher-order thinking is one of the important goals of modern education,and innovative teaching model is an effective way to achieve this goal.Aiming at the inadequacy of the existing moral di...Cultivating students'higher-order thinking is one of the important goals of modern education,and innovative teaching model is an effective way to achieve this goal.Aiming at the inadequacy of the existing moral dilemma stories approach in the transformation of knowledge and behavior,this research constructs a new Project Based Learning-Ethical Dilemma Stories(PBL-EDS)Teaching Model applicable to China's secondary education stage based on the innovative features of the moral dilemma stories approach on the core competencies,taking the chemistry subject as an example to carry out practice,and puts forward suggestions for the implementation of the teaching model.Chemistry as an example to carry out the practice,and suggestions are made for the implementation of the teaching model.展开更多
采用Monty Hall Dilemma的经典研究范式,探讨了大学生被试在不同提示条件下对MHD问题的解决情况,结果发现只有在条件关系提示下,MHD的作业成绩才得到了明显的改善,但是正确率也只有35.7%。这表明MHD问题困难的原因很可能是多方面的,如...采用Monty Hall Dilemma的经典研究范式,探讨了大学生被试在不同提示条件下对MHD问题的解决情况,结果发现只有在条件关系提示下,MHD的作业成绩才得到了明显的改善,但是正确率也只有35.7%。这表明MHD问题困难的原因很可能是多方面的,如认为主持人的行为完全是随机事件,很难意识到参与者的最初选择与主持人打开特定盒子间的三种条件关系;多数被试作出选择的理由是非理性的,如“坚持第一选择,相信自己的直觉”;不能正确判断MHD问题的内在概率关系以及缺乏认真思考的动力等。展开更多
Prisoner’s Dilemma is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In Prisoner’s Dilemma Richard Powers narrates a multiform of dilemma mainly narrating Eddie Hobson’...Prisoner’s Dilemma is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In Prisoner’s Dilemma Richard Powers narrates a multiform of dilemma mainly narrating Eddie Hobson’s traumatic history,along with Eddie’s attempt to carry out a strategy—Eddie’s ideal Hobstown which is supposed to cope with the confused dilemma.Pow⁃ers’strategic moral insights are revealed by assuming that each player feels sympathy for the other and a moral cooperative instead of antagonistic solution to the Prisoner’s Dilemma will be found.展开更多
The“prisoner’s dilemma”illustrates that everyone is rationally thinking about maximizing their own interests and taking their own best strategies,but the end result is counterproductive.In Prisoner’s Dilemma Richa...The“prisoner’s dilemma”illustrates that everyone is rationally thinking about maximizing their own interests and taking their own best strategies,but the end result is counterproductive.In Prisoner’s Dilemma Richard Powers describes multiformareas of dilemma;to lose balance;to make choices;and ask each other:what to do next?It is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In most cases,the prisoner's dilemma is more about the number of defeats in the game,and even a major loss of society.Individual rationality is likely to be a collective disregard,and if everyone is acting on the principle of self-interest,it is often the result that everyone is lost.Powers expresses his philosophical insight:Until a cooperative instead of antagonistic solution is collectively agreed upon,we still remain imprisoned in an interminable and oppressive struggle and conflict decided by self-interest and rational control,which is also a moral response to historical consciousness of postmodernism.展开更多
The iterated prisoner's dilemma(IPD) is an ideal model for analyzing interactions between agents in complex networks. It has attracted wide interest in the development of novel strategies since the success of tit-...The iterated prisoner's dilemma(IPD) is an ideal model for analyzing interactions between agents in complex networks. It has attracted wide interest in the development of novel strategies since the success of tit-for-tat in Axelrod's tournament. This paper studies a new adaptive strategy of IPD in different complex networks, where agents can learn and adapt their strategies through reinforcement learning method. A temporal difference learning method is applied for designing the adaptive strategy to optimize the decision making process of the agents. Previous studies indicated that mutual cooperation is hard to emerge in the IPD. Therefore, three examples which based on square lattice network and scale-free network are provided to show two features of the adaptive strategy. First, the mutual cooperation can be achieved by the group with adaptive agents under scale-free network, and once evolution has converged mutual cooperation, it is unlikely to shift. Secondly, the adaptive strategy can earn a better payoff compared with other strategies in the square network. The analytical properties are discussed for verifying evolutionary stability of the adaptive strategy.展开更多
Hepatic epithelioid hemangioendothelioma(HEHE) is a rare category of vascular tumor with uncertain malignant potential. It commonly presents nonspecific and variable clinical manifestations, ranging from asymptomatic ...Hepatic epithelioid hemangioendothelioma(HEHE) is a rare category of vascular tumor with uncertain malignant potential. It commonly presents nonspecific and variable clinical manifestations, ranging from asymptomatic to hepatic failure. In addition, laboratory measurements and imaging features also lack specificity in the diagnosis of HEHE. The aim of the present study is to highlight the dilemma and challenges in the preoperative diagnosis of HEHE, and to enhance awareness of the range of hepatobiliary surgery available in patients with multiple hepatic nodular lesions on imaging. In these patients, HEHE should at least be considered in the differential diagnosis.展开更多
Heart failure (HF), a complex clinical syndrome due to structural or functional disorder of the heart, is a major global health issue, with a prevalence of over 5.8 million in the USA alone, and over 23 million worl...Heart failure (HF), a complex clinical syndrome due to structural or functional disorder of the heart, is a major global health issue, with a prevalence of over 5.8 million in the USA alone, and over 23 million worldwide. As a leading cause of hospitalizations among patients aged 65 years or older, HF is a major consumer of healthcare resources, creating a substantial strain on the healthcare system. This paper discusses the epidemiology of HF, financial impact, and multifaceted predicaments in end-stage HF care. A search was conducted on the U.S National Library of Medicine website (www.pubmed.gov) using keywords such as end-stage heart failure, palliative care, ethical dilemmas. Despite the poor prognosis of HF (worse than that for many cancers), many HF patients, caregivers, and clinicians are unaware of the poor prognosis. In addition, the unpredictable clinical trajectory of HF complicates the planning of end-of-life care, such as palliative care and hospice, leading to underutilization of such resources. In conclusion, ethical dilemmas in end-stage HF are numerous, embroiling not only the patient, but also the caregiver, healthcare team, and society.展开更多
Natural selection opposes the evolution of cooperation unless specific mechanisms are at work in Prisoner's Dilemma. By taking advantage of the modern control theory, the controller design is discussed and the optima...Natural selection opposes the evolution of cooperation unless specific mechanisms are at work in Prisoner's Dilemma. By taking advantage of the modern control theory, the controller design is discussed and the optimal control is designed for promoting cooperation based on the recent advances in mechanisms for the evolution of cooperation. Two con- trol strategies are proposed: compensation control strategy for the cooperator when playing against a defector and reward control strategy for cooperator when playing against a coop- erator. The feasibility and effectiveness of these control strategies for promoting cooperation in different stages are analyzed. The reward for cooperation can't prevent defection from being evolutionary stable strategy (ESS). On the other hand, compensation for the coopera- tor can't prevent defection from emerging and sustaining. By considering the effect and the cost, an optimal control scheme with constraint on the admissible control set is put forward. By analyzing the special nonlinear system of replicator dynamics, the exact analytic solution of the optimal control scheme is obtained based on the maximum principle. Finally, the effectiveness of the proposed method is illustrated by examples.展开更多
This paper studies the evolutionary prisoner's dilemma game on a highly clustered community network in which the clustering coefficient and the community size can be tuned. It finds that the clustering coefficient in...This paper studies the evolutionary prisoner's dilemma game on a highly clustered community network in which the clustering coefficient and the community size can be tuned. It finds that the clustering coefficient in such a degree-homogeneous network inhibits the emergence of cooperation for the entire range of the payoff parameter. Moreover, it finds that the community size can also have a marked influence on the evolution of cooperation, with a larger community size leading to not only a lower cooperation level but also a smaller threshold of the payoff parameter above which cooperators become extinct.展开更多
Purpose: The aim of this study was to illuminate the connotation of “dilemma” regarding the use of physical restraint on elderly patients as represented by female nurses working in general wards at community hospita...Purpose: The aim of this study was to illuminate the connotation of “dilemma” regarding the use of physical restraint on elderly patients as represented by female nurses working in general wards at community hospitals who also live with elderly adults at home. Method: The study used the questionnaire method with an independently prepared questionnaire. Participants: The objective of the study was explained to the persons in charge of nursing in the selected 17 hospitals, and 1929. Finally, this study of participants were 524 female nurses working in general 54 wards (excluding the emergency wards of psychiatry, pediatrics, obstetrics, outpatients, operating rooms, and intensive care units) at community hospitals who also live with elderly adults at home. Results and conclusions: Cronbach’s overall coefficient for the 20 items of dilemma was high (0.78) and the factor analysis extracted four dilemma factors as having a characteristic value of 1 (Kaiser-Meyer-Olkin measure value = 0.81) with a cumulative contribution ratio of 64.5%. The high Cronbach’s for these items (0.86, 0.88, 0.87 and 0.81) confirmed the internal consistencies. With respect to the dilemma where nurses working in general wards at community hospitals who also live with elderly adults at home are faced with the physical restraint of elderly persons, four factors in the clarification of the dilemma were extracted: accomplishment of medical-treatment and accident prevention, characteristic features in nursing for elderly patients with dementia, healthcare professional relationship in nursing for elderly patients with dementia, and priorities on the accident prevention for elderly patients with dementia. Therefore, the construction of four systems to cope with these dilemmas is suggested. These systems would enable practising nurses to: (i) institution of policies to encourage discussion between nurses and other medical staff to reach consensus on treatment;(ii) allocating elderly care specialists to wards to promote alternatives to restraints;(iii) establishment of safety standards to define nurses’ responsibilities;and (iv) institution of continuous ethical education for nurses.展开更多
In this paper, we introduce an asymmetric payoff distribution mechanism into the evolutionary prisoner's dilemma game (PDG) on Newman Watts social networks, and study its effects on the evolution of cooperation. Th...In this paper, we introduce an asymmetric payoff distribution mechanism into the evolutionary prisoner's dilemma game (PDG) on Newman Watts social networks, and study its effects on the evolution of cooperation. The asymmetric payoff distribution mechanism can be adjusted by the parameter α: if α〉 0, the rich will exploit the poor to get richer; if α 〈 0, the rich are forced to offer part of their income to the poor. Numerical results show that the cooperator frequency monotonously increases with c~ and is remarkably promoted when c~ 〉 0. The effects of updating order and self-interaction are also investigated. The co-action of random updating and self-interaction can induce the highest cooperation level. Moreover, we employ the Gini coefficient to investigate the effect of asymmetric payoff distribution on the the system's wealth distribution. This work may be helpful for understanding cooperative behaviour and wealth inequality in society.展开更多
Access to safe water supply has great influence on the health, economic productivity and quality of life of the people. But meeting this need is one of the major challenges facing the rural communities of Nigeria toda...Access to safe water supply has great influence on the health, economic productivity and quality of life of the people. But meeting this need is one of the major challenges facing the rural communities of Nigeria today. The purpose of this review paper is to determine whether water supply have contributed effectively to health, social, and cultural development of Nigerian rural communities. Over 70% of households in rural communities do not have access to improved water supply. They rely solely on self-water supply (free source) such as rivers, perennial streams, water ponds and unprotected wells which is susceptible to water borne diseases such as typhoid fever, cholera, dysentery, malaria parasites etc. These rural populations are engaged in farming activities with low income level living in small scattered settlements thus, making provision of piped water supply very difficult. Governments’ interventions towards rural water supply have been through the provision of hand-operated boreholes and wells. These sources yield little or no water during the dry season and are prone to frequent breakdown;leading water crisis and shortages. This situation forces households especially the women and children to spend more time walking longer distances during the dry season to trot water for domestic purposes. Given the fact that the publicly operated water supply have not been able to cope with increasing demand, there is a need for a paradigm shift from the public monopoly of water supply to an innovative approach. Rainwater harvesting technology appears to be one of such alternative approaches.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61963013).
文摘We propose a computing model in which individuals can automatically adjust their interaction intensity with their mentor according to the learning effect.This model is designed to investigate the cooperative dynamics of the spatial prisoner's dilemma.More specifically,when the cumulative payoff of a learner is more than his reference earning,he will strengthen his interaction with his mentor;otherwise,he will reduce it.The experimental results indicate that this mechanism can improve the emergence of cooperation in a networked population and that the driving coefficient of interaction intensity plays an important role in promoting cooperation.Interestingly,under a certain social dilemma condition,there exists a minimal driving coefficient that leads to optimal cooperation.This occurs due to a positive feedback effect between the individual's satisfaction frequency and the number of effective neighbors.Moreover,we find that the experimental results are in accord with theoretical predictions obtained from an extension of the classical pair-approximation method.Our conclusions obtained by considering relationships with mentors can provide a new perspective for future investigations into the dynamics of evolutionary games within structured populations.
文摘Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival and spiritual dilemma of Indian women in the transformation of India’s modernization.The novel depicts in both content and form the plight of Indian women’s physical and spiritual dependence under the traditional concepts of arranged marriages,caste marriages,dowry system and patriarchal will,and shows the process of women’s body and self-consciousness gradually moving from vitality to extinction.
文摘The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, characterized by independence and specialization, is designed to mitigate these shortcomings. However, the implementation of third-party assessment faces challenges too. This paper intends to improve the third-party assessment system and to realize the legislative purpose of the system. Based on social research, discussions and exchanges with relevant parties, and the existing research results, this paper analyzes the challenges and possible optimization measures for the third-party assessment. The challenges include repulsion from policy-making bodies, insufficient independence of assessment bodies, disparity of assessment quality, and limited application of assessment outcomes. Possible optimization measures include promoting fair competition culture, increasing the acceptance of third-party assessment from policy-making bodies, enhancing the quality of third-party assessment, clarifying the relationship between policy-making bodies and assessment bodies, ensuring the independence of third-party assessments, and promoting the application of assessment results.
文摘This paper comprehensively analyzes the development opportunities and realistic dilemmas faced by adult higher education in China in the new era,and puts forward corresponding strategies as solutions.With the construction of a learning society,the development of digital technology,and the popularization of the concept of lifelong learning,adult higher education has unprecedented development opportunities.At the same time,these forms of education are facing a series of dilemmas due to challenges such as unsound guarantee mechanisms and traditional enrollment competition.Through the establishment of perfect legal and policy guarantees,transformation of school running mode,meeting the diversified needs of learners,and other multi-faceted measures,the development of adult higher education can be effectively promoted to meet the needs of individual and social development.
基金The 2020 Guangxi Higher Education Undergraduate Teaching Reform Project“Research and Practice of Blended Course Evaluation System Based on College Students’Learning Effect”(Project number:2020JGZ116)。
文摘Blended teaching has emerged as a prominent subject in the recent reform and innovation of higher education.It has become imperative and guiding for colleges and universities to embrace a mixed teaching approach that aligns with the evolving needs of education and teaching in the new era.This paper aims to provide a comprehensive overview of the research status surrounding blended teaching,encompassing fundamental issues,teaching design,practical guidance,teaching effectiveness,and evaluation.By critically examining the current challenges associated with blended teaching,this study proposes optimization strategies including enhancing student participation and interaction,promoting deep learning,improving teachers’preparedness,teaching technologies,and curriculum design capabilities,strengthening top-level design,and perfecting evaluation and incentive mechanisms.These strategies provide new directions for the reform of blended teaching.
基金supported by the Macao Foundation's research project"An Empirical Study on the Training Standards for Innovative Talents in the Guangdong-Hong Kong-Macao Greater Bay Area"(MF2315)the 2021 General Project of the 14th Five-Year Plan of Philosophy and Social Sciences of Guangdong Province of China(Number:GD21CJY08).
文摘Cultivating students'higher-order thinking is one of the important goals of modern education,and innovative teaching model is an effective way to achieve this goal.Aiming at the inadequacy of the existing moral dilemma stories approach in the transformation of knowledge and behavior,this research constructs a new Project Based Learning-Ethical Dilemma Stories(PBL-EDS)Teaching Model applicable to China's secondary education stage based on the innovative features of the moral dilemma stories approach on the core competencies,taking the chemistry subject as an example to carry out practice,and puts forward suggestions for the implementation of the teaching model.Chemistry as an example to carry out the practice,and suggestions are made for the implementation of the teaching model.
文摘采用Monty Hall Dilemma的经典研究范式,探讨了大学生被试在不同提示条件下对MHD问题的解决情况,结果发现只有在条件关系提示下,MHD的作业成绩才得到了明显的改善,但是正确率也只有35.7%。这表明MHD问题困难的原因很可能是多方面的,如认为主持人的行为完全是随机事件,很难意识到参与者的最初选择与主持人打开特定盒子间的三种条件关系;多数被试作出选择的理由是非理性的,如“坚持第一选择,相信自己的直觉”;不能正确判断MHD问题的内在概率关系以及缺乏认真思考的动力等。
文摘Prisoner’s Dilemma is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In Prisoner’s Dilemma Richard Powers narrates a multiform of dilemma mainly narrating Eddie Hobson’s traumatic history,along with Eddie’s attempt to carry out a strategy—Eddie’s ideal Hobstown which is supposed to cope with the confused dilemma.Pow⁃ers’strategic moral insights are revealed by assuming that each player feels sympathy for the other and a moral cooperative instead of antagonistic solution to the Prisoner’s Dilemma will be found.
文摘The“prisoner’s dilemma”illustrates that everyone is rationally thinking about maximizing their own interests and taking their own best strategies,but the end result is counterproductive.In Prisoner’s Dilemma Richard Powers describes multiformareas of dilemma;to lose balance;to make choices;and ask each other:what to do next?It is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In most cases,the prisoner's dilemma is more about the number of defeats in the game,and even a major loss of society.Individual rationality is likely to be a collective disregard,and if everyone is acting on the principle of self-interest,it is often the result that everyone is lost.Powers expresses his philosophical insight:Until a cooperative instead of antagonistic solution is collectively agreed upon,we still remain imprisoned in an interminable and oppressive struggle and conflict decided by self-interest and rational control,which is also a moral response to historical consciousness of postmodernism.
基金supported by the National Natural Science Foundation(NNSF)of China(61603196,61503079,61520106009,61533008)the Natural Science Foundation of Jiangsu Province of China(BK20150851)+4 种基金China Postdoctoral Science Foundation(2015M581842)Jiangsu Postdoctoral Science Foundation(1601259C)Nanjing University of Posts and Telecommunications Science Foundation(NUPTSF)(NY215011)Priority Academic Program Development of Jiangsu Higher Education Institutions,the open fund of Key Laboratory of Measurement and Control of Complex Systems of Engineering,Ministry of Education(MCCSE2015B02)the Research Innovation Program for College Graduates of Jiangsu Province(CXLX1309)
文摘The iterated prisoner's dilemma(IPD) is an ideal model for analyzing interactions between agents in complex networks. It has attracted wide interest in the development of novel strategies since the success of tit-for-tat in Axelrod's tournament. This paper studies a new adaptive strategy of IPD in different complex networks, where agents can learn and adapt their strategies through reinforcement learning method. A temporal difference learning method is applied for designing the adaptive strategy to optimize the decision making process of the agents. Previous studies indicated that mutual cooperation is hard to emerge in the IPD. Therefore, three examples which based on square lattice network and scale-free network are provided to show two features of the adaptive strategy. First, the mutual cooperation can be achieved by the group with adaptive agents under scale-free network, and once evolution has converged mutual cooperation, it is unlikely to shift. Secondly, the adaptive strategy can earn a better payoff compared with other strategies in the square network. The analytical properties are discussed for verifying evolutionary stability of the adaptive strategy.
基金Supported by National Nature Science of China,No.30801111Science and Technology Support Project of Sichuan Province,No.2014SZ0002-10
文摘Hepatic epithelioid hemangioendothelioma(HEHE) is a rare category of vascular tumor with uncertain malignant potential. It commonly presents nonspecific and variable clinical manifestations, ranging from asymptomatic to hepatic failure. In addition, laboratory measurements and imaging features also lack specificity in the diagnosis of HEHE. The aim of the present study is to highlight the dilemma and challenges in the preoperative diagnosis of HEHE, and to enhance awareness of the range of hepatobiliary surgery available in patients with multiple hepatic nodular lesions on imaging. In these patients, HEHE should at least be considered in the differential diagnosis.
文摘Heart failure (HF), a complex clinical syndrome due to structural or functional disorder of the heart, is a major global health issue, with a prevalence of over 5.8 million in the USA alone, and over 23 million worldwide. As a leading cause of hospitalizations among patients aged 65 years or older, HF is a major consumer of healthcare resources, creating a substantial strain on the healthcare system. This paper discusses the epidemiology of HF, financial impact, and multifaceted predicaments in end-stage HF care. A search was conducted on the U.S National Library of Medicine website (www.pubmed.gov) using keywords such as end-stage heart failure, palliative care, ethical dilemmas. Despite the poor prognosis of HF (worse than that for many cancers), many HF patients, caregivers, and clinicians are unaware of the poor prognosis. In addition, the unpredictable clinical trajectory of HF complicates the planning of end-of-life care, such as palliative care and hospice, leading to underutilization of such resources. In conclusion, ethical dilemmas in end-stage HF are numerous, embroiling not only the patient, but also the caregiver, healthcare team, and society.
文摘Natural selection opposes the evolution of cooperation unless specific mechanisms are at work in Prisoner's Dilemma. By taking advantage of the modern control theory, the controller design is discussed and the optimal control is designed for promoting cooperation based on the recent advances in mechanisms for the evolution of cooperation. Two con- trol strategies are proposed: compensation control strategy for the cooperator when playing against a defector and reward control strategy for cooperator when playing against a coop- erator. The feasibility and effectiveness of these control strategies for promoting cooperation in different stages are analyzed. The reward for cooperation can't prevent defection from being evolutionary stable strategy (ESS). On the other hand, compensation for the coopera- tor can't prevent defection from emerging and sustaining. By considering the effect and the cost, an optimal control scheme with constraint on the admissible control set is put forward. By analyzing the special nonlinear system of replicator dynamics, the exact analytic solution of the optimal control scheme is obtained based on the maximum principle. Finally, the effectiveness of the proposed method is illustrated by examples.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 70671079, 60674050, 60736022 and 60528007)National 973 Program (Grant No 2002CB312200)+1 种基金National 863 Program (Grant No 2006AA04Z258)11-5 project (Grant NoA2120061303)
文摘This paper studies the evolutionary prisoner's dilemma game on a highly clustered community network in which the clustering coefficient and the community size can be tuned. It finds that the clustering coefficient in such a degree-homogeneous network inhibits the emergence of cooperation for the entire range of the payoff parameter. Moreover, it finds that the community size can also have a marked influence on the evolution of cooperation, with a larger community size leading to not only a lower cooperation level but also a smaller threshold of the payoff parameter above which cooperators become extinct.
文摘Purpose: The aim of this study was to illuminate the connotation of “dilemma” regarding the use of physical restraint on elderly patients as represented by female nurses working in general wards at community hospitals who also live with elderly adults at home. Method: The study used the questionnaire method with an independently prepared questionnaire. Participants: The objective of the study was explained to the persons in charge of nursing in the selected 17 hospitals, and 1929. Finally, this study of participants were 524 female nurses working in general 54 wards (excluding the emergency wards of psychiatry, pediatrics, obstetrics, outpatients, operating rooms, and intensive care units) at community hospitals who also live with elderly adults at home. Results and conclusions: Cronbach’s overall coefficient for the 20 items of dilemma was high (0.78) and the factor analysis extracted four dilemma factors as having a characteristic value of 1 (Kaiser-Meyer-Olkin measure value = 0.81) with a cumulative contribution ratio of 64.5%. The high Cronbach’s for these items (0.86, 0.88, 0.87 and 0.81) confirmed the internal consistencies. With respect to the dilemma where nurses working in general wards at community hospitals who also live with elderly adults at home are faced with the physical restraint of elderly persons, four factors in the clarification of the dilemma were extracted: accomplishment of medical-treatment and accident prevention, characteristic features in nursing for elderly patients with dementia, healthcare professional relationship in nursing for elderly patients with dementia, and priorities on the accident prevention for elderly patients with dementia. Therefore, the construction of four systems to cope with these dilemmas is suggested. These systems would enable practising nurses to: (i) institution of policies to encourage discussion between nurses and other medical staff to reach consensus on treatment;(ii) allocating elderly care specialists to wards to promote alternatives to restraints;(iii) establishment of safety standards to define nurses’ responsibilities;and (iv) institution of continuous ethical education for nurses.
基金Project supported by the Major State Basic Research Development Program of China (Grant No. 2004CB318109)Program for New Century Excellent Talents in University of China (Grant No. NCET-07-0787)the National Natural Science Foundation of China (Grant No. 70601026)
文摘In this paper, we introduce an asymmetric payoff distribution mechanism into the evolutionary prisoner's dilemma game (PDG) on Newman Watts social networks, and study its effects on the evolution of cooperation. The asymmetric payoff distribution mechanism can be adjusted by the parameter α: if α〉 0, the rich will exploit the poor to get richer; if α 〈 0, the rich are forced to offer part of their income to the poor. Numerical results show that the cooperator frequency monotonously increases with c~ and is remarkably promoted when c~ 〉 0. The effects of updating order and self-interaction are also investigated. The co-action of random updating and self-interaction can induce the highest cooperation level. Moreover, we employ the Gini coefficient to investigate the effect of asymmetric payoff distribution on the the system's wealth distribution. This work may be helpful for understanding cooperative behaviour and wealth inequality in society.
文摘Access to safe water supply has great influence on the health, economic productivity and quality of life of the people. But meeting this need is one of the major challenges facing the rural communities of Nigeria today. The purpose of this review paper is to determine whether water supply have contributed effectively to health, social, and cultural development of Nigerian rural communities. Over 70% of households in rural communities do not have access to improved water supply. They rely solely on self-water supply (free source) such as rivers, perennial streams, water ponds and unprotected wells which is susceptible to water borne diseases such as typhoid fever, cholera, dysentery, malaria parasites etc. These rural populations are engaged in farming activities with low income level living in small scattered settlements thus, making provision of piped water supply very difficult. Governments’ interventions towards rural water supply have been through the provision of hand-operated boreholes and wells. These sources yield little or no water during the dry season and are prone to frequent breakdown;leading water crisis and shortages. This situation forces households especially the women and children to spend more time walking longer distances during the dry season to trot water for domestic purposes. Given the fact that the publicly operated water supply have not been able to cope with increasing demand, there is a need for a paradigm shift from the public monopoly of water supply to an innovative approach. Rainwater harvesting technology appears to be one of such alternative approaches.