997 resultados para WESTERN UNITED-STATES


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Night sharks, Carcharhinus signatus, are an oceanic species generally occurring in outer continental shelf waters in the western North Atlantic Ocean including the Caribbean Sea and Gulf of Mexico. Although not targeted, night sharks make up a segment of the shark bycatch in the pelagic longline fishery. Historically, night sharks comprised a significant proportion of the artisanal Cuban shark fishery but today they are rarely caught. Although information from some fisheries has shown a decline in catches of night sharks, it is unclear whether this decline is due to changes in fishing tactics, market, or species identification. Despite the uncertainty in the decline, the night shark is currently listed as a species of concern due to alleged declines in abundance resulting from fishing effort, i.e. overutilization. To assess their relevance to the species of concern list, we collated available information on the night shark to provide an analysis of its status. Night shark landings were likely both over- and under-reported and thus probably did not reflect all commercial and recreational catches, and overall they have limited relevance to the current status of the species. Average size information has not changed considerably since the 1980’s based on information from the pelagic longline fishery when corrected for gear bias. Analysis of biological information indicates night sharks have intrinsic rates of increase (r) about 10% yr–1 and have moderate rebound potential and an intermediate generation time compared to other sharks. An analysis of trends in relative abundance from four data sources gave conflicting results, with one series in decline, two series increasing, and one series relatively flat. Based on the analysis of all currently available information, we believe the night shark does not qualify as a species of concern but should be retained on the prohibited species list as a precautionary approach to management until a more comprehensive stock assessment can be conducted.

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This study, part of a broader investigation of the history of exploitation of right whales, Balaena glacialis, in the western North Atlantic, emphasizes U.S. shore whaling from Maine to Delaware (from lat. 45°N to 38°30'N) in the period 1620–1924. Our broader study of the entire catch history is intended to provide an empirical basis for assessing past distribution and abundance of this whale population. Shore whaling may have begun at Cape Cod, Mass., in the 1620’s or 1630’s; it was certainly underway there by 1668. Right whale catches in New England waters peaked before 1725, and shore whaling at Cape Cod, Martha’s Vineyard, and Nantucket continued to decline through the rest of the 18th century. Right whales continued to be taken opportunistically in Massachusetts, however, until the early 20th century. They were hunted in Narragansett Bay, R.I., as early as 1662, and desultory whaling continued in Rhode Island until at least 1828. Shore whaling in Connecticut may have begun in the middle 1600’s, continuing there until at least 1718. Long Island shore whaling spanned the period 1650–1924. From its Dutch origins in the 1630’s, a persistent shore whaling enterprise developed in Delaware Bay and along the New Jersey shore. Although this activity was most profi table in New Jersey in the early 1700’s, it continued there until at least the 1820’s. Whaling in all areas of the northeastern United States was seasonal, with most catches in the winter and spring. Historically, right whales appear to have been essentially absent from coastal waters south of Maine during the summer and autumn. Based on documented references to specific whale kills, about 750–950 right whales were taken between Maine and Delaware, from 1620 to 1924. Using production statistics in British customs records, the estimated total secured catch of right whales in New England, New York, and Pennsylvania between 1696 and 1734 was 3,839 whales based on oil and 2,049 based on baleen. After adjusting these totals for hunting loss (loss-rate correction factor = 1.2), we estimate that 4,607 (oil) or 2,459 (baleen) right whales were removed from the stock in this region during the 38-year period 1696–1734. A cumulative catch estimate of the stock’s size in 1724 is 1,100–1,200. Although recent evidence of occurrence and movements suggests that right whales continue to use their traditional migratory corridor along the U.S. east coast, the catch history indicates that this stock was much larger in the 1600’s and early 1700’s than it is today. Right whale hunting in the eastern United States ended by the early 1900’s, and the species has been protected throughout the North Atlantic since the mid 1930’s. Among the possible reasons for the relatively slow stock recovery are: the very small number of whales that survived the whaling era to become founders, a decline in environmental carrying capacity, and, especially in recent decades, mortality from ship strikes and entanglement in fishing gear.

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This study investigates the changes of the North Atlantic subtropical high (NASH) and its impact on summer precipitation over the southeastern (SE) United States using the 850-hPa geopotential height field in the National Centers forEnvironmental Prediction (NCEP) reanalysis, the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40), long-term rainfall data, and Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) model simulations during the past six decades (1948-2007). The results show that the NASH in the last 30 yr has become more intense, and its western ridge has displaced westward with an enhanced meridional movement compared to the previous 30 yr. When the NASH moved closer to the continental United States in the three most recent decades, the effect of the NASH on the interannual variation of SE U.S. precipitation is enhanced through the ridge's north-south movement. The study's attribution analysis suggested that the changes of the NASH are mainly due to anthropogenic warming. In the twenty-first century with an increase of the atmospheric CO2 concentration, the center of the NASH would be intensified and the western ridge of the NASH would shift farther westward. These changes would increase the likelihood of both strong anomalously wet and dry summers over the SEUnited States in the future, as suggested by the IPCC AR4 models. © 2011 American Meteorological Society.

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© 2014, Springer-Verlag Berlin Heidelberg.This study assesses the skill of advanced regional climate models (RCMs) in simulating southeastern United States (SE US) summer precipitation and explores the physical mechanisms responsible for the simulation skill at a process level. Analysis of the RCM output for the North American Regional Climate Change Assessment Program indicates that the RCM simulations of summer precipitation show the largest biases and a remarkable spread over the SE US compared to other regions in the contiguous US. The causes of such a spread are investigated by performing simulations using the Weather Research and Forecasting (WRF) model, a next-generation RCM developed by the US National Center for Atmospheric Research. The results show that the simulated biases in SE US summer precipitation are due mainly to the misrepresentation of the modeled North Atlantic subtropical high (NASH) western ridge. In the WRF simulations, the NASH western ridge shifts 7° northwestward when compared to that in the reanalysis ensemble, leading to a dry bias in the simulated summer precipitation according to the relationship between the NASH western ridge and summer precipitation over the southeast. Experiments utilizing the four dimensional data assimilation technique further suggest that the improved representation of the circulation patterns (i.e., wind fields) associated with the NASH western ridge substantially reduces the bias in the simulated SE US summer precipitation. Our analysis of circulation dynamics indicates that the NASH western ridge in the WRF simulations is significantly influenced by the simulated planetary boundary layer (PBL) processes over the Gulf of Mexico. Specifically, a decrease (increase) in the simulated PBL height tends to stabilize (destabilize) the lower troposphere over the Gulf of Mexico, and thus inhibits (favors) the onset and/or development of convection. Such changes in tropical convection induce a tropical–extratropical teleconnection pattern, which modulates the circulation along the NASH western ridge in the WRF simulations and contributes to the modeled precipitation biases over the SE US. In conclusion, our study demonstrates that the NASH western ridge is an important factor responsible for the RCM skill in simulating SE US summer precipitation. Furthermore, the improvements in the PBL parameterizations for the Gulf of Mexico might help advance RCM skill in representing the NASH western ridge circulation and summer precipitation over the SE US.

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OBJECTIVES:

To determine the prevalence of cataract and pseudophakia/aphakia in the United States and to project the expected change in these prevalence figures by 2020.

METHODS:

Summary prevalence estimates of cataract and of pseudophakia/aphakia were prepared separately for black, white, and Hispanic persons (for whom only cataract surgery data were available) in 5-year age intervals starting at 40 years for women and men. The estimates were based on a standardized definition of various types of cataract: cortical, greater than 25% of the lens involved; posterior subcapsular, present according to the grading system used in each study; and nuclear, greater than or equal to the penultimate grade in the system used. Data were collected from major population-based studies in the United States, and, where appropriate, Australia, Barbados, and Western Europe. The age-, gender-, and race/ethnicity-specific rates were applied to 2000 US Census data, and projected population figures for 2020, to obtain overall estimates.

RESULTS:

An estimated 20.5 million (17.2%) Americans older than 40 years have cataract in either eye, and 6.1 million (5.1%) have pseudophakia/aphakia. Women have a significantly (odds ratio = 1.37; 95% confidence interval, 1.26-1.50) higher age-adjusted prevalence of cataract than men in the United States. The total number of persons who have cataract is estimated to rise to 30.1 million by 2020; and for those who are expected to have pseudophakia/aphakia, to 9.5 million.

CONCLUSION:

The number of Americans affected by cataract and undergoing cataract surgery will dramatically increase over the next 20 years as the US population ages.

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Youth violence is a global problem. Few studies have examined whrther the prevalence or predictors of youth violence are similar in comparable Western countries like Australia and the United States (US). In the current article, analyses are conducted using two waves of data collected as part of a longitudinal study of adolescent development in approximately 4,000 students aged 12 to 16 years in Victoria, Australia and Washington State, US. Students completed a self-report survey of problem behaviours including violent behaviour, as well as risk and protective factors across five domains (individual, family, peer, school, community). Compared to Washington State, rates of attacking or beating another over the past 12 months were lower in Victoria for females in the first survey and higher for Victorian males in the follow-up survey. Preliminary analyses did not show state-specific predictors of violent behaviour. In the final multivariate analyses of the combined Washington State and Victorian samples, protective factors were being female and student emotion control. Risk factors were prior violent behaviour, family conflict, association with violent peers, community disorganisation, community norms favourable to drug use, school suspensions and arrests. Given the similarity of influential factors in North America and Australia, application of US early intervention and prevention programs may be warranted, with some tailoring to the Australian context.

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Includes bibliography

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Includes bibliography.

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United States Trade Developments 2013-2014, is an annual report prepared by the ECLAC Washington Office. It provides an overview of the most relevant trade developments in the United States trade relations with Latin America and the Caribbean and the measures that inhibit the free flow of goods among countries in the Western Hemisphere. The report presents trade figures and trends over the last few years to illustrate the nature of the U.S. engagement through trade with the world and with the Latin America and Caribbean region. Special emphasis was given to trade among the U.S., Canada, and Mexico on the 20th anniversary of the North American Free Trade Agreement, and to trade with Brazil, the second U.S .trade partner in the region, after Mexico.

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United States Trade Developments, 2014-2015, provides an overview of the most relevant trade developments in the United States trade relations with Latin America and the Caribbean and the measures that inhibit the free flow of goods among countries in the Western Hemisphere.The report presents trade figures and trends over the last few years to illustrate the nature of the U.S. engagement through trade with the world and with the Latin America and Caribbean region.

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There is an ongoing mission in Afghanistan; a mission driven by external political forces. At its core this mission hopes to establish peace, to protect the populace, and to install democracy. Each of these goals has remained just that, a goal, for the past eight years as the American and international mission in Afghanistan has enjoyed varied levels of commitment. Currently, the stagnant progress in Afghanistan has led the international community to become increasingly concerned about the viability of a future Afghan state. Most of these questions take root in the question over whether or not an Afghan state can function without the auspices of international terrorism. Inevitably, the normative question of what exactly that government should be arises from this base concern. In formulating a response to this question, the consensus of western society has been to install representative democracy. This answer has been a recurring theme in the post Cold War era as states such as Bosnia and Somalia bear witness to the ill effects of external democratic imposition. I hypothesize that the current mold of externally driven state-building is unlikely to result in what western actors seek it to establish: representative democracy. By primarily examining the current situation in Afghanistan, I claim that external installation of representative democracy is modally flawed in that its process mandates choice. Representative democracy by definition constitutes a government reflective of its people, or electorate. Thus, freedom of choice is necessary for a functional representative democracy. From this, one can deduce that because an essential function of democracy is choice, its implementation lies with the presence of choice. State-building is an imposition that eliminates that necessary ingredient. The two stand as polar opposites that cannot effectively collaborate. Security, governing capacity, and development have all been targeted as measurements of success in Afghanistan. The three factors are generally seen as mutually constitutive; so improved security is seen as improving governing capacity. Thus, the recent resurgence of the Taliban in Afghanistan and a deteriorating security environment moving forward has demonstrated the inability of the Afghan government to govern. The primary reason for the Afghan government’s deficiencies is its lack of legitimacy among its constituency. Even the use of the term ‘constituency’ must be qualified because the Afghan government has often oscillated between serving the people within its territorial borders and the international community. The existence of the Afghan state is so dependent on foreign aid and intervention that it has lost policy-making and enforcing power. This is evident by the inability of Afghanistan to engage in basic sovereign state activities as maintaining a national budget, conducting elections, providing for its own national security, and deterring criminality. The Afghan state is nothing more than a shell of a government, and indicative of the failings that external state-building has with establishing democracy.

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Soil dust is a major constituent of airborne particles in the global atmosphere. Dust plumes frequently cover huge areas of the earth; they are one of the most prominent and commonly visible features in satellite imagery. Dust is believed to play a role in many biogeochemical processes, but the importance of dust in these processes is not well understood because of the dearth of information about the global distribution of dust and its physical, chemical, and mineralogical properties. This paper describes some features of the large-scale distribution of dust and identifies some of the geological characteristics of important source areas. The transport of dust from North Africa is presented as an example of possible long-range dust effects, and the impact of African dust on environmental processes in the western North Atlantic and the southeastern United States is assessed. Dust transported over long distances usually has a mass median diameter <10 μm. Small wind-borne soil particles show signs of extensive weathering; consequently, the physical and chemical properties of the particles will greatly depend on the weathering history in the source region and on the subsequent modifications that occur during transit in the atmosphere (typically a period of a week or more). To fully understand the role of dust in the environment and in human health, mineralogists will have to work closely with scientists in other disciplines to characterize the properties of mineral particles as an ensemble and as individual particles especially with regard to surface characteristics.

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This Capstone represents a qualitative analysis of survey responses concerning river recreation management policies and techniques in the Western United States. Respondents were asked about management topics including permits and fees, monitoring, enforcement, resource management, recreational experience, and current and future demand for whitewater rafting. Responses with consistent results include those for questions concerning permits for commercial uses, justification of fees, and enforcement, while responses with variation in results were received for questions concerning permits for private uses, agency self-sufficiency, monitoring, and use capacity. Most respondents do not expect a significant increased demand for commercial or private boating in the next five years. Respondents that do expect an increase do not see a need for additional commercial outfitters.