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We prove that a hyperbolic group admits a strongly aperiodic subshift of finite type if and only if it has at most one end. [ABSTRACT FROM AUTHOR]

Throughout history, pandemics have posed significant challenges to governments. Examination of the ways that governments have responded to pandemics can contribute to the U.S. government's ability to react in the future. We utilize past cases of Severe Acute Respiratory Syndrome (SARS) and multiple forms of influenza to identify specific challenges governments have faced. Based on that knowledge, we discuss the major issues that the United States will have to address in the event of a future pandemic. KEY WORDS: disease, influenza, pandemic, quarantine, response, SARS, Introduction The threat of pandemic disease, whether naturally occurring or terrorist inflicted, is real. In today's world of rapid global transportation, any location on Earth can be reached in less [...]

Recent literature indicates that females are more resistant to shock-, trauma-, and sepsis-induced immune dysfunction and organ injury than are males. Consequently, using trauma-hemorrhagic shock (T/HS) and burn models, we tested whether the neutrophil response to trauma occurred in a sexually dimorphic fashion and, if so, the role of sex hormones. Neutrophil activation, as reflected by CD11b expression and respiratory burst activity, was increased to a greater extent in male rats than in female rats after T/HS or burn injury. Testosterone appeared to potentiate neutrophil activation, because castration reduced neutrophil activation, whereas ovariectomy had little effect. Mechanistically, this sexually dimorphic neutrophil response appeared to be due to both cellular and humoral factors. Evidence for a cellular difference between male and female neutrophils is based on the observation that naive female neutrophils were more resistant to activation by burn or T/HS plasma and lymph than naive male neutrophils and that this resistance varied over the estrus cycle. Additionally, the humoral environment was more neutrophil activating in male rats, because burn and T/HS plasma and lymph from male rats activated naive male neutrophils to a greater extent than comparable samples from females. Last, on the basis of in vitro experiments examining the effects of estrogen on calcium signaling, it appears that estrogen limits trauma-induced neutrophil activation, at least in part, by limiting the entry of calcium into the cell via store-operated calcium entry mechanisms. In conclusion, there is a striking sexual dimorphism in neutrophil responses after trauma, and these changes reflect both cellular resistance to activation as well as a less activating humoral environment. polymorphonuclear neutrophils doi:10.1152/ajpheart00694.2005

Background: Nonsteroidal anti-inflammatory drugs are commonly prescribed after rotator cuff repair. These agents can impair bone formation, but no studies have evaluated their impact on tendon-to-bone healing. Hypothesis: Traditional nonselective [...]

Municipal governments' efforts in preparing for possible terrorist events are critical to effective homeland security. Using data gathered from a nationwide sample of municipal officials, the authors identify determinants of homeland security preparedness in U.S. cities, across several attitudinal and behavioral indicators. The authors find that perceptions of terror threat vulnerability and response capacity are tied to factors such as city size and budgetary constraints. Perhaps more important, the authors show that administrative capacity demonstrates consistent explanatory power for both perceived policy commitment and specific preparedness actions. From these analyses, the authors outline several key policy implications for homeland security policy making. Keywords: homeland security; terrorism; cities and terror; disaster preparedness; hazard management; emergency management

ABSTRACT America's current war on terrorism has led presidency scholars to revisit past U.S. antiterrorism measures. This study employs a case study approach to examine President Ronald Reagan's decision to [...]

Chiefs of staff in the modern presidency usually assume three major roles during their tenure: administrator, adviser, and guardian. Through original survey data, this article explores these roles by examining six chiefs of staff who served during the Reagan-Bush era: James Baker, Donald Regan, Howard Baker, Kenneth Duberstein, John Sununu, and Samuel Skinner. Based on the evidence, Howard Baker and James Baker were perceived as the most effective chiefs of staff in performing these three major functions. Not surprisingly, the Reagan administration prospered during both Bakers' tenures., Introduction: The Significance of the White House Chief of Staff The Clinton presidency began with great hope and expectation. Political observers marveled at the 1992 Clinton-Gore campaign machine as the [...]

ABSTRACT The Carter administration fashioned a multi-faceted strategy to help push the Airline Deregulation Act of 1978 through the Congress: Administrative (relaxation of aviation regulation through the Civil Aeronautics Board); [...]

The frequency with which presidents issue executive orders is an important area of inquiry for students of executive politics, because this instrument can shape policy in a quick, direct manner that is outside the purview of the legislative arena. We construct a probabilistic-based empirical model that is used to explain variation in the number of presidential executive orders issued during the 1953-1994 annual period. Using event count regression techniques, these results indicate that the use of executive orders by presidents is significantly related to the legislative success they enjoy, the partisan composition of Congress, macroeconomic conditions, and the rate of growth in federal executive branch employment. The main implication of the study is that a president's willingness to issue executive orders is significantly related to a combination of legislative, public prestige, and managerial/institutional considerations. Thus, presidential use of executive orders is conditioned on different types of causal factors, and not solely attributable to the "institutionalized presidency" or legislative relations with Congress, as suggested in previous research on the topic.