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171.
Punctuated equilibrium theory (PET) suggests that the policy process is characterized by long periods of incremental change and short periods of punctuated change. The impetus for the latter is usually a focusing event that breaks open policy monopolies, allowing for major changes in legislative decision making. While a burgeoning body of literature, a shortcoming in the PET literature is that it has yet to explain why focusing events and subsequent breakdowns in policy monopolies sometimes fail to result in punctuated policy. We integrate theories on cultural change with punctuated equilibrium to explain why focusing events do not always result in the dramatic policy changes that we might expect. Specifically, we use the context of national energy policy and the lexical database, Google Ngram Viewer, to trace punctuating energy‐related events and the occurrence or lack thereof subsequent policy change from 1952 to 2000.  相似文献   
172.
About half of the nations that experience civil war eventually relapse into renewed conflict within a few years after the original war ends. This observation has motivated a stream of research into the factors that affect the risk of peace failure in the aftermath of civil war. While the outcome of the previous civil war—for example, military victory versus peace agreement—structures the post-war environment in ways that affect the risk of peace failure, the capacity of the post-war state to enact and implement policies that affect the incentives for and capacity of groups to undertake armed violence as a means of advancing their interests should also affect the risks of peace failure. Using Geddes’ categories of nondemocratic regime types, we will present a theory of how different regime types have varying capacities to repress and/or implement accommodative policies that affect the risk of peace failure. We test propositions derived from this theory with a series of event history models. Our findings suggest that while peace agreements significantly increase the duration of post-civil war peace, peace agreements involving some types of nondemocratic regimes actually increase the risk of post-civil war peace failure.  相似文献   
173.
Quantitative literature discussing violence in civil conflicts tends towards a typical model of engagement between governments and revolutionaries. Whilst recent work has shown the significant impact of multiple anti-government groups, a further feature remains understudied—the role of pro-state militants. This article theorizes a “violence premium” when such groups arise, which leads to all connected groups devoting greater energy to conflict than they would in isolation. Employing duration analysis and data from The Troubles in Northern Ireland, where Republicans act as revolutionary insurgents, Loyalists as pro-state militants, and the British Army as government forces, the violence premium is empirically confirmed. Both Loyalists and Republicans deviate from their underlying strategies to attack more frequently when violence by their rivals increases, with Republicans and the British Army engaging in the same way. An extended analysis, accounting for the status of the victim, shows that the violence premium resulting from interaction between Loyalists and Republicans targeted only the civilian population of Northern Ireland, elucidating the sectarian component of The Troubles. These results show that including all conflict parties and considering how they are linked are important features in studies that aim to determine the net level of violence in civil conflicts.  相似文献   
174.
175.
Negotiation training evaluation tends to be short-term, aspectual and piecemeal; evaluations often focus on only one or two salient outcomes of training. This essay presents a model for negotiation training evaluation research that offers a broad conceptualization of the hypothesized individual and group-level effects of training in collaborative negotiation. The model assesses change at the individual level in conflict-related cognitions, attitudes, affect and behaviors; and at the group level in conflict outcomes and work climate. The Negotiation Evaluation Survey (NES), a time-delayed, multi-source feedback approach to assessment and development, is presented as a means of addressing some of the conceptual and methodological problems inherent in more common methods of training evaluation. An illustrative assessment of one model of collaborative negotiation training for adults, the Coleman/Raider Model, is presented. The results, implications, and future research challenges are discussed.  相似文献   
176.
利用aroA基因建立鸡传染性鼻炎PCR诊断方法   总被引:1,自引:0,他引:1  
利用aroA基因设计了1对引物,分别对10株标准副鸡嗜血杆菌(HPG)菌株、14株分离的HPG菌株进行PCR扩增,结果均得到了与预期大小一致的片段,而对10株非HPG菌株和3株病毒进行扩增则无相应片段产生;该PCR能检测出10个菌细胞.与常规PCR方法相比,aroA-PCR的敏感性更高.  相似文献   
177.
Adverse childhood experiences (ACEs) have been identified as a key risk factor associated with a wide range of negative life outcomes, including juvenile delinquency. Much less work has explored whether certain combinations of ACEs, or typologies of trauma, exist, and whether or not these subgroups are differentially associated with certain youth-level and/or community-level characteristics. The current study uses latent class analysis to examine ACE typologies among a sample of over 92,000 juvenile offenders between the ages of 10 and 18 in the state of Florida (52% male, 37.3% White, 46.8% Black, 15.9% Hispanic). Multilevel multinomial logistic regression is used to assess the relationship between both individual- and community-level factors and class membership. The findings suggest that a total of five distinct ACE typologies exist among the sample of juvenile offenders, and age, race, and sex were significantly associated with class membership. Additionally, controlling for individual-level characteristics, community-level measures of immigrant concentration, residential instability, and two separate measures of concentrated disadvantage and affluence were significantly related to class membership. This study contributes to the understanding of adverse childhood experiences, and adds to existing knowledge regarding the relationship between contextual factors and childhood abuse, maltreatment, and trauma. The identification of ACE subgroups with distinct characteristics may help guide prevention strategies and tailor treatment provided by the juvenile justice system.  相似文献   
178.
Psychological empowerment encompasses several key aspects of youth civic and sociopolitical development. Most research has focused on psychological empowerment’s emotional component, which entails learned hopefulness about one’s own ability to participate in and lead community change efforts. Fewer studies have assessed critical awareness of how social power operates—psychological empowerment’s cognitive component. The confluence of these two components has been termed critical hopefulness. A complex relationship exists between these two components, and previous research has found relatively small proportions of participants reporting both high levels of critical awareness and simultaneously high levels of hopefulness about their ability to exert influence in the sociopolitical domain. The current study of urban high school students in the Northeastern U.S. (n?=?389; 53.5% female) investigates heterogeneity according to these two components of psychological empowerment. Latent class cluster analyses were conducted and seven distinct groups of participants emerged. Students identifying as Hispanic/Latinx were more likely to be classified into a profile group exhibiting critical hopefulness. Differences were observed between psychological empowerment profile groups on self-reported levels of psychological sense of community, civic engagement, and social justice orientation. Furthermore, a larger proportion of this overall sample was classified into groups that exhibited critical hopefulness than in a previous study of adults. These findings provide useful insights for efforts to engage young people in civic life and to promote sociopolitical development.  相似文献   
179.
Document examiners sometimes eliminate writers on the basis of differences which are given too much weight. This article is an attempt to explain some conditions whereby differences in the writing of one individual are misinterpreted as significant differences, when they are actually caused by conditions which are unknown to the examiner.  相似文献   
180.
The activity of calcium pumping adenosine triphosphatase (Ca2+-ATPase) in cardiac sarcoplasmic reticulum plays a pivotal role in myocardiac contraction-relaxation. The Ca2+-ATPase activity is controlled by phosphorylation and dephosphorylation of a sarcoplasmic reticulum protein "phospholamban" in response to neurotransmitters and drugs. To clarify the role of Ca2+-ATPase in the development of cardiac rigor mortis, we examined the changes of cardiac rigidity and cardiac sarcoplasmic reticulum Ca2+-ATPase activity up to 5 h after the decapitation of rats. Fifteen minutes after decapitation, the rats showed a cardiac rigidity on left ventricles. After 30 min, rigidity was obvious over the whole heart. After 1 h, the rigidity reached a high degree which was maintained for the rest of the observation period. On the other hand, the Ca2+-ATPase activity controlled by phosphorylation and dephosphorylation of phospholamban did not change for the whole observation period (5 h). Another Ca2+-ATPase activity representing the total amount of Ca2+-ATPase in sarcoplasmic reticulum gradually decreased. The data suggest that no significant phosphorylation or dephosphorylation of phospholamban occurs for a short time, at least for 5 h, after death and that the Ca2+-ATPase tends to relax the myocardium against the development of cardiac rigor mortis.  相似文献   
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