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Chaos theory, informational needs, and natural disasters   总被引:2,自引:0,他引:2  
This study applies chaos theory to a system-wide analysis of crisis communication in a natural disaster. Specifically, we analyze crisis communication during the 1997 Red River Valley flood in Minnesota and North Dakota. This flood, among the worst in modern American history, consumed entire metropolitan areas, displacing thousands of people. The conditions and decisions leading to the disaster, and the subsequent reactions are retraced. Communication related to river crest predictions (fractals), the shock at the magnitude of the crisis (cosmology episode), novel forms of reorganizing (self-organization), and agencies that aided in establishing a renewed order (strange attractors) are evaluated. Ultimately, we argue that preexisting sensemaking structures favoring rationalized, traditional views of a complex system led officials to make inappropriately unequivocal predictions and ultimately diminished the effectiveness of the region's crisis communication and planning.  相似文献   
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An ongoing debate regarding the nature of therapeutic communities concerns the extent to which these communities reinforce the ideologies of individualism and community. This article engages this discussion through a process of social text analysis informed by the dialogism theory of Russian philosopher and literary scholar Mikhail Bakhtin. Dialogism seeks to understand the multiple voices interpenetrating particular utterances, revealing an emergent social construction of meaning. Applying this approach to examples of discourse from a prominent therapeutic community, Alcoholics Anonymous, illustrates how meaning in the discourse of this movement can be understood to emerge among the interplay between the ideologies of individualism and community as expressed within the movement's narrative practice.  相似文献   
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BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease.  相似文献   
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ABSTRACT

This essay engages the possibilities and pitfalls of UNESCO’s Memory of the World program for fostering “global archival memory.” Archives function as rhetorical weapons for both political control and social justice within national and regional contexts. The constitution of global archival memory shifts archives’ borders beyond nation-bound contexts, creating space for contention, deliberation, and debate within a presentist transnational arena. Approaching archives as symbols capable of marshaling cross-cultural identifications furthers memory scholars’ conceptions of transnational memories and communities. It responds to rhetorical scholars’ calls to further engage archives, while drawing on archival studies, memory studies, and rhetorical theories of memory.  相似文献   
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This contribution reviews existing research on media coverage of doping in Germany. Based on a keyword search, 22 works were identified. The review aims to provide a survey of the state of the art in terms of questions addressed, methods and results as well as blind spots and methodological deficits. Moreover, directions for future research are outlined. Although research is characterized by substantial methodological heterogeneity, central results can be presented following the influential approach of Bette and Schimank. In accordance with their ideas media coverage of doping is characterized by scandalization, personalization and moralization. However, shortfalls of theoretical perspective and methodological shortcomings are noted. These deficits serve as an inspiration for future research.  相似文献   
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Conclusion     
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