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Adaptive interaction driven by the learning effect in the spatial prisoner's dilemma
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作者 李佳奇 张建磊 刘群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期160-169,共10页
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
关键词 self-adapting interaction evolutionary game MENTOR spatial prisoner's dilemma
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Benefit community promotes evolution of cooperation in prisoners’ dilemma game
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作者 Jianwei Wang Jialu He +3 位作者 Fengyuan Yu Wei Chen Rong Wang Ke Yu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期603-608,共6页
Exploring the emergence and maintenance of cooperation in social dilemma is valuable and it arises considerable concerns of many researchers. In this paper, we propose a mechanism to promote cooperation, called benefi... Exploring the emergence and maintenance of cooperation in social dilemma is valuable and it arises considerable concerns of many researchers. In this paper, we propose a mechanism to promote cooperation, called benefit community,in which cooperators linking together form a common benefit community and all their payoffs obtained from game are divided coequally. The robustness of conclusions is tested for the PDG(prisoners' dilemma game) on square lattice and WS small world network. We find that cooperation can be promoted by this typical mechanism, especially, it can diffuse and prevail more easily and rapidly on the WS small world network than it on the square lattice, even if a big temptation to defect b. Our research provides a feasible direction to resolve the social dilemma. 展开更多
关键词 coevolution cooperation prisoners' dilemma GAME BENEFIT COMMUNITY
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Prevalence of Hepatitis B and Associated Factors in the Garoua Central Prison, Cameroon: A Cross-Sectional Study
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作者 Mohamadou Abdou Galdima Adamou Dodo Balkissou +9 位作者 Guy Roger Nsenga Djapa Winnie Tatiana Bekolo Nga Gilles Aghoagni Antonin Wilson Ndjitoyap Ndam Ali Abas Mathurin Pierre Kowo Firmin Ankouane Andoulo Dominique Noah Noah Oudou Njoya Servais Albert Fiacre Eloumou Bagnaka 《Open Journal of Gastroenterology》 CAS 2024年第5期174-183,共10页
Introduction: Hepatitis B virus (HBV) infection is a major public health problem in Cameroon. Garoua city is the headquarters of the North Region of Cameroon, where the HBV prevalence is among the highest of the count... Introduction: Hepatitis B virus (HBV) infection is a major public health problem in Cameroon. Garoua city is the headquarters of the North Region of Cameroon, where the HBV prevalence is among the highest of the country. The aim of this study was to determine the prevalence of HBsAg carriage and associated factors among persons incarcerated in the Garoua Central Prison. Methods: It was a cross-sectional study conducted from July 1 to July 31, 2023 at the Garoua Central prison. We included all prisoners willing to participate in the study and who gave their verbal consent. We collected data using a pre-established data entry form and we used rapid test for blood screening for HBV surface antigen (HBs Ag) with ELISA confirmation. Data were analyzed using the R<sup>®</sup> software for Windows. After the univariate analysis, we selected associated variables to HBV infection with p-value p-value was set at 5%. Results: We included 1389 prisoners out of which 97.6% were male. The median age (IQR) of the study population was 28 (23 - 35) years. The median (IQR) duration of incarceration was 12 (6 - 26) months and the mean (±sd) number of incarcerations was 1.24 (±0.6). HBV prevalence was estimated at 14.8% (95% CI: 13.0 - 16.7). Upon uni- and multivariate analysis, no risk factor was significantly associated with viral hepatitis B infection in our study population. Conclusion: The prevalence of Hepatitis B was high in the Garoua Central Prison, but there were no additional risk factors for HBV infection. There is a need to include the Garoua Central Prison and by the way other prisons in the country in the chronic viral hepatitis care program. 展开更多
关键词 Hepatitis B prison Associated factors Cameroon
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Prevalence and features of SARS-CoV-2 infection in prisons in Tuscany
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作者 Cristina Stasi Martina Pacifici +3 位作者 Caterina Milli Francesco Profili Caterina Silvestri Fabio Voller 《World Journal of Experimental Medicine》 2024年第1期70-77,共8页
BACKGROUND Prisons can be a reservoir for infectious diseases,including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),due to the very intimate nature of the living spaces and the large number of people f... BACKGROUND Prisons can be a reservoir for infectious diseases,including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),due to the very intimate nature of the living spaces and the large number of people forced to share them.AIM To investigate the SARS-CoV-2 epidemiology in prisons,this study evaluated the infection incidence rate in prisoners who underwent nasopharyngeal swabs.METHODS This is an observational cohort study.Data collection included information on prisoners who underwent nasopharyngeal swab testing for SARS-CoV-2 and the results.Nasopharyngeal swab tests for SARS-CoV-2 were performed between 15 February 2021 and 31 May 2021 for prisoners with symptoms and all new arrivals to the facility.Another section included information on the diagnosis of the disease according to the International Classification of Diseases,Ninth Revision,and Clinical Modification.RESULTS Up until the 31 May 2021,79.2%of the prisoner cohort(n=1744)agreed to a nasopharyngeal swab test(n=1381).Of these,1288 were negative(93.3%)and 85 were positive(6.2%).A significant association[relative risk(RR)]was found only for the risk of SARS-CoV-2 infection among foreigners compared to Italians[RR=2.4,95%confidence interval(CI):1.2-4.8].A positive association with SARS-CoV-2 infection was also found for inmates with at least one nervous system disorder(RR=4,95%CI:1.8-9.1).The SARS-CoV-2 incidence rate among prisoners is significantly lower than in the general population in Tuscany(standardized incidence ratio 0.7,95%CI:0.6-0.9).CONCLUSION In the prisoner cohort,screening and rapid access to health care for the immigrant population were critical to limiting virus transmission and subsequent morbidity and mortality in this vulnerable population. 展开更多
关键词 SARS-CoV-2 Epidemiology prison PREVALENCE FOREIGNERS Swab tests
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Prisoners' Dilemma Supergame on Rectangle Lattice
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作者 Zhongxing Ye Jingshu Chen 《Open Journal of Applied Sciences》 2013年第1期7-11,共5页
In this paper a class of large supergames, i.e., infinitely repeated games played by many players are studied. The players located on the vertex set of planar rectangle lattice play several basic games with his neighb... In this paper a class of large supergames, i.e., infinitely repeated games played by many players are studied. The players located on the vertex set of planar rectangle lattice play several basic games with his neighbors. The basic game is two-person prisoners’ dilemma game with asymmetric payoffs. Under the conditions of the pre-specified updating rules and the transition probabilities, the relevant stochastic process of strategy evolution forms a Markovian process. The simulation results about the long-run behavior are provided. 展开更多
关键词 prisoners' dilemma Supergame Planar RECTANGLE LATTICE MARKOV Process INVARIANT Measure Equilibrium
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Dilemmas and Optimization of Third-Party Assessment System in Chinese Fair Competition Review
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作者 Cui Xu Mingyu Hu 《Open Journal of Applied Sciences》 2024年第8期2039-2049,共11页
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
关键词 Fair Competition Review Self-Review Third-Party Assessment dilemma Optimization
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The “Panchatantra” Narrative Structure and the Writing of Indian Women’s Dilemma in Suraj Ka Satvan Ghoda
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作者 CEN Rui 《Journal of Literature and Art Studies》 2024年第7期567-575,共9页
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
关键词 Suraj Ka Satvan Ghoda Dharamvir Bharati The“Panchatantra”narrative structure dilemma writing
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The Opportunities,Dilemmas,and Paths for the Development of Adult Higher Education in the New Era
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作者 Yin Huang 《Journal of Contemporary Educational Research》 2024年第4期264-269,共6页
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
关键词 Adult higher education OPPORTUNITIES dilemmaS PATHS
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A Study of a Moral Dilemma Stories Teaching Model Focusing on the Development of Higher-Order Thinking --"Synthetic polymers" as an example
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作者 Lin Tang Yi Dai 《教育技术与创新》 2024年第1期27-35,共9页
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
关键词 higher-order thinking moral dilemma stories teaching model secondary education
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Research Status,Practical Dilemmas,and Optimization Strategies of Blended Teaching in Universities
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作者 Zhiying Zhu Yinxia Wei 《Journal of Contemporary Educational Research》 2024年第7期210-215,共6页
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
关键词 Blended teaching Research status Practical dilemma Optimization strategy
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Effects of Topological Randomness on Cooperation in a Deterministic Prisoner's Dilemma Game
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作者 章梅 杨俊忠 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期31-36,共6页
In this work, we consider an evolutionary prisoner's dilemma game on a homogeneous random network with the richest-following strategy adoption rule. By constructing homogeneous random networks from a regular ring gra... In this work, we consider an evolutionary prisoner's dilemma game on a homogeneous random network with the richest-following strategy adoption rule. By constructing homogeneous random networks from a regular ring graph, we investigate the effects of topologicaJ randomness on cooperation. In contrast to the ordinary view that the presence of smaJ1 amount of shortcuts in ring graphs favors cooperation, we find the cooperation inhibition by weak topological randomness. The explanations on the observations are presented. 展开更多
关键词 deterministic prisoners' dilemma game topological randomness COOPERATION
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Defection or Cooperation—Richard Power’s Moral Insights in Prisoner’s Dilemma
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作者 梁渊 宋祝 +1 位作者 陈益 周永胜 《海外英语》 2021年第4期239-241,共3页
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
关键词 DEFECTION COOPERATION MoralInsights prisoner’s dilemma
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Richard Power’s Philosophical Thoughts in Prisoner’s Dilemma
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作者 梁渊 陈益 魏澜 《海外英语》 2020年第11期213-214,220,共3页
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
关键词 prisoner’s dilemma DEFECTION COOPERATION Philosophical Thoughts
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An Adaptive Strategy via Reinforcement Learning for the Prisoner's Dilemma Game 被引量:8
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作者 Lei Xue Changyin Sun +2 位作者 Donald Wunsch Yingjiang Zhou Fang Yu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第1期301-310,共10页
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
关键词 Complex network prisoner’s dilemma reinforcement learning temporal differences learning
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Intentional ingestions of foreign objects among prisoners: A review 被引量:10
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作者 David C Evans Thomas R Wojda +2 位作者 Christian D Jones Andrew J Otey Stanislaw P Stawicki 《World Journal of Gastrointestinal Endoscopy》 CAS 2015年第3期162-168,共7页
The intentional ingestion of foreign objects(IIFO) is described more commonly in prison populations than in the general population, with an estimated annual incidence of 1 in 1900 inmates in our state correctional fac... The intentional ingestion of foreign objects(IIFO) is described more commonly in prison populations than in the general population, with an estimated annual incidence of 1 in 1900 inmates in our state correctional facilities. Incidents often involve ingestion of small metal objects(e.g., paperclips, razor blades) or other commonly available items like pens or eating utensils. Despite ingestion of relatively sharp objects, most episodes can be clinically managed with either observation or endoscopy. Surgery should be reserved for those with signs or symptoms of gastrointestinal perforation or obstruction. For those with a history of IIFO, efforts should focus on prevention of recurrenceas subsequent episodes are associated with higher morbidity, significant healthcare and security costs. The pattern of IIFO is often repetitive, with escalation both in frequency of ingestions and in number of items ingested. Little is known about successful prevention strategies, but efforts to monitor patients and provide psychiatric care are potential best-practice strategies. This article aims to provide state-of-the art review on the topic, followed by a set of basic recommendations. 展开更多
关键词 Ingestion FOREIGN body ENDOSCOPY prisonER Swallower Prevention RECURRENCE
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THE OPTIMAL CONTROL FOR PROMOTING THE COOPERATION IN EVOLUTION GAME GENERATED BY PRISONER'S DILEMMA 被引量:2
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作者 王先甲 董瑞 陈琳 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期73-92,共20页
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
关键词 evolutionary games prisoner's dilemma evolution of cooperation promoting cooperation control optimal control
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Hepatitis C virus infection and prisoners: Epidemiology, outcome and treatment 被引量:3
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作者 Rosa Zampino Nicola Coppola +2 位作者 Caterina Sagnelli Giovanni Di Caprio Evangelista Sagnelli 《World Journal of Hepatology》 CAS 2015年第21期2323-2330,共8页
The studies on hepatitis C virus(HCV) infection in prison populations are few and mostly cross-sectional. We analyzed prevalently the articles appearing on Pub Med in the last ten years. HCV infection is frequent in p... The studies on hepatitis C virus(HCV) infection in prison populations are few and mostly cross-sectional. We analyzed prevalently the articles appearing on Pub Med in the last ten years. HCV infection is frequent in prisoners, prevalences ranging from 3.1% to 38% according to the HCV endemicity in the geographical location of the prison and in the countries of origin of the foreign prisoners and to the prevalence of intravenous drug use, which is the most important risk factor for HCV infection, followed by an older age of prisoners and previous prison terms. HCV replication in anti-HCVpositive cases varies from 45% to 90% in different studies, and the most common HCV genotypes are generally 1 and 3. The response to antiviral treatment is similar in prisoners to that of the general population. Unfortunately, treatment is administered less frequently to prisoners because of the difficulties in management and follow-up. The new directly acting antivirals offer a good therapy option for inmates because of their good efficacy, short duration of treatment and low incidence of side effects. The efforts of the prison authorities and medical staff should be focused on reducing the spread of HCV infection in prisons by extending the possibility of follow-up and treatment to more prisoners with chronic hepatitis C. 展开更多
关键词 prisoners Management Treatment CARE CHRONIC hepati
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Evolutionary prisoner's dilemma game on highly clustered community networks 被引量:1
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作者 刘永奎 李智 +1 位作者 陈小杰 王龙 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2623-2628,共6页
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
关键词 prisoner's dilemma COOPERATION clustering coefficient community structure
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Evolutionary prisoner’s dilemma on Newman-Watts social networks with an asymmetric payoff distribution mechanism 被引量:1
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作者 杜文博 曹先彬 +1 位作者 杨涵新 胡茂彬 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期17-21,共5页
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
关键词 prisoner's dilemma game COOPERATION complex social networks
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Prevalence of hepatitis C virus infection and its related risk factors in drug abuser prisoners in Hamedan-Iran 被引量:5
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作者 Amir Houshang Mohammad Alizadeh Seyed Moayed Alavian +1 位作者 Khalil Jafari Nastaran Yazdi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第26期4085-4089,共5页
AIM:Recent studies in Iran has shown that prevalence of hepatitis C virus (HCV) infection among Iranian prisoners is high, in spite of low HCV seroprevalence in general population. METHODS: This study was carried out ... AIM:Recent studies in Iran has shown that prevalence of hepatitis C virus (HCV) infection among Iranian prisoners is high, in spite of low HCV seroprevalence in general population. METHODS: This study was carried out in the central prison of Hamedan - Iran, in year 2002. Inmates were interviewed using a standard questionnaire including demographic, imprisonment history and HCV-related risk behaviors items. Thereafter, the sera drawn from the participants were tested for anti-HIV and anti-HCV antibodies. RESULTS: A total number of 427 drug abuser inmates participated in our study. Three hundred and ninety-seven (93%) were men and 30 (7%) were women. Total number of IV drug abusers (IDA) and non-IV drug abusers (NIDA) was 149 (34.9%) and 278 (65.1%), respectively. The overall rate of antibody positivity among inmates was 0.9% for HIV and 30% for HCV. Of all IDAs, 31.5% and of NIDAs, 29.1% had serological evidence of HCV infection. CONCLUSION: The seroprevalence of HCV infection among drug abuser prisoners in comparison with the general population in Iran, is very high (30% vs in italics 0.2%). Our results indicate the importance of policies to prevent transmission of HCV infection during and following incarceration. 展开更多
关键词 Hepatitis C virus prisoners Drug abusers Iran
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