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Selected AbstractsA dynamic mass budget for toxaphene in North AmericaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2002Matthew MacLeod Abstract A continental-scale dynamic mass budget for toxaphene in North America is presented, based on available information on physicochemical properties, usage patterns, and reported environmental concentrations and using the Berkeley-Trent North American mass balance contaminant fate model (BETR North America). The model describes contaminant fate in 24 ecological regions of North America, including advective transport between regions in the atmosphere, freshwater, and near-shore coastal water. The dynamic mass budget accounts for environmental partitioning, transport, and degradation of the estimated 534 million kg of toxaphene that were used in North America as an insecticide and piscicide between 1945 and 2000. Satisfactory agreement exists between model results and current and historically reported concentrations of toxaphene in air, water, soil, and sediments throughout North America. An estimated 15 million kg of toxaphene are believed to remain in active circulation in the North American environment in the year 2000, with the majority in soils in the southern United States and Mexico, where historic usage was highest. Approximately 70% of total toxaphene deposition from the atmosphere to the Great Lakes is attributed to sources outside the Great Lakes Basin, and an estimated total of 3.9 million kg of toxaphene have been transported to this region from other parts of the continent. The toxaphene mass budget presented here is believed to be the first reported continental-scalemultimedia mass budget for any contaminant. [source] Testosterone 1,-hydroxylation by human cytochrome P450 3A4FEBS JOURNAL, Issue 19 2004Joel A. Krauser Human cytochrome P450 3A4 forms a series of minor testosterone hydroxylation products in addition to 6,-hydroxytestosterone, the major product. One of these, formed at the next highest rate after the 6,- and 2,-hydroxy products, was identified as 1,-hydroxytestosterone. This product was characterized from a mixture of testosterone oxidation products using an HPLC-solid phase extraction-cryoprobe NMR/time-of-flight mass spectrometry system, with an estimated total of ,,6 µg of this product. Mass spectrometry established the formula as C19H29O3 (MH+ 305.2080). The 1-position of the added hydroxyl group was established by correlated spectroscopy and heteronuclear spin quantum correlation experiments, and the ,-stereochemistry of the added hydroxyl group was assigned with a nuclear Overhauser correlated spectroscopy experiment (1,-H). Of several human P450s examined, only P450 3A4 formed this product. The product was also formed in human liver microsomes. [source] NUTRIENTS DISCHARGED TO THE MISSISSIPPI RIVER FROM EASTERN IOWA WATERSHEDS, 1996.1997,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2000Kent D. Becher ABSTRACT: The introduction of nutrients from chemical fertilizer, animal manure, wastewater, and atmospheric deposition to the eastern Iowa environment creates a large potential for nutrient transport in watersheds. Agriculture constitutes 93 percent of all land use in eastern Iowa. As part of the U.S. Geological Survey National Water Quality Assessment Program, water samples were collected (typically monthly) from six small and six large watersheds in eastern Iowa between March 1996 and September 1997. A Geographic Information System (GIS) was used to determine land use and quantify inputs of nitrogen and phosphorus within the study area. Streamliow from the watersheds is to the Mississippi River. Chemical fertilizer and animal manure account for 92 percent of the estimated total nitrogen and 99.9 percent of the estimated total phosphorus input in the study area. Total nitrogen and total phosphorus loads for 1996 were estimated for nine of the 12 rivers and creeks using a minimum variance unbiased estimator model. A seasonal pattern of concentrations and loads was observed. The greatest concentrations and loads occur in the late spring to early summer in conjunction with row-crop fertilizer applications and spring nmoff and again in the late fall to early winter as vegetation goes into dormancy and additional fertilizer is applied to row-crop fields. The three largest rivers in eastern Iowa transported an estimated total of 79,000 metric tons of total nitrogen and 6,800 metric tons of total phosphorus to the Mississippi River in 1996. The estimated mass of total nitrogen and total phosphorus transported to the Mississippi River represents about 19 percent of all estimated nitrogen and 9 percent of all estimated phosphorus input to the study area. [source] The value of conserving whales: the impacts of cetacean-related tourism on the economy of rural West ScotlandAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2003E.C.M. Parsons Abstract 1.During the tourist season of 2000, interview surveys were conducted with those involved in whale-watching in West Scotland. The groups included in the study were boat operators (32), visitor-centre managers (8), tourists on whale-watching trips (324), general tourists to West Scotland (673) and local residents (189). The latter two groups were interviewed for comparison of responses of those engaged in whale-watching against the views of the local community and tourists in general. From the data provided by these interviews, estimates for the economic value of this specialist sector of the Scottish tourism industry were calculated. 2.Extrapolating from the surveys, in the year 2000, an estimated total of approximately 242 000 tourists were involved in cetacean-related tourism activities in West Scotland. 3.In 2000, 59 full-time and one part-time jobs were estimated to be created as the direct result of cetacean-related tourism, with 38% of these positions being seasonal. 4.Cetacean-related tourism was estimated to account for 2.5% of the total income from tourism in the region. In remote coastal areas, cetacean-related tourism may account for as much as 12% of the area's total tourism income. 5.The direct economic income (i.e. expenditure on excursion tickets) from cetacean tourism activities was estimated to be £1.77 million per annum. 6.A 23% of surveyed whale watchers visited West Scotland specifically to go on whale-watching trips. The associated expenditure (accommodation, travel, food, etc.) from tourists being brought to rural West Scotland solely due to the presence of whales represented £5.1 million in additional tourism income for the region. 7.In addition to the above tourists, 16% of surveyed whale watchers stayed in West Scotland an extra night as a result of going on a whale-watching trip; thus generating a further £0.9 million of additional associated expenditure (extra accommodation, food, etc.). 8.The total gross income generated (directly and indirectly) by cetacean-related tourism in rural West Scotland was estimated at £7.8 million. 9.In comparison with established whale-watching industries (in countries such as the USA, Canada and New Zealand) the total expenditure by tourists on whale watching in West Scotland is low. However, cetacean tourism in West Scotland is still a relatively young industry and still developing. 10.The value of the non-consumptive utilization of cetaceans (i.e. whale-watching) to rural, coastal communities in West Scotland was three times greater than the value of the consumptive utilization of cetaceans (i.e. commercial whaling) for rural, coastal communities in Norway. 11.This study demonstrates that live cetaceans in Scotland can provide notable financial benefits and, therefore, their conservation has an economic value. Copyright © 2003 John Wiley & Sons, Ltd. [source] Injuries in Youth Football: National Emergency Department Visits during 2001,2005 for Young and Adolescent PlayersACADEMIC EMERGENCY MEDICINE, Issue 3 2009Michael J. Mello MD Abstract Objectives:, Limited research exists describing youth football injuries, and many of these are confined to specific regions or communities. The authors describe U.S. pediatric football injury patterns receiving emergency department (ED) evaluation and compare injury patterns between the younger and older youth football participants. Methods:, A retrospective analysis of ED data on football injuries was performed using the National Electronic Injury Surveillance System,All Injury Program. Injury risk estimates were calculated over a 5-year period (2001,2005) using participation data from the National Sporting Goods Association. Injury types are described for young (7,11 years) and adolescent (12,17 years) male football participants. Results:, There were an estimated total of 1,060,823 visits to U.S. EDs for males with football-related injuries. The most common diagnoses in the younger group (7,11 years) were fracture/dislocation (29%), sprain/strain (27%), and contusion (27%). In the older group (ages 12,17 years), diagnoses included sprain/strain (31%), fracture/dislocation (29%), and contusion (23%). Older participants had a significantly higher injury risk of injury over the 5-year study period: 11.0 (95% confidence interval [CI] = 9.2 to 12.8) versus 6.1 (95% CI = 4.8 to 7.3) per 1,000 participants/year. Older participants had a higher injury risk across all categories, with the greatest disparity being with traumatic brain injury (TBI), 0.8 (95% CI = 0.6 to 1.0) versus 0.3 (95% CI = 0.2 to 0.4) per 1,000 participants/year. Conclusions:, National youth football injury patterns are similar to those previously reported in community and cohort studies. Older participants have a significantly higher injury risk, especially with TBI. [source] Measuring Prevalence: Increasing ,active prevalence' of cancer in Western Australia and its implications for health servicesAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 2 2002Kate J. Brameld Objective:To measure the active and total prevalence of cancer in Western Australia from 1990,98 and to examine trends in utilisation of hospital services by prevalent cancer patients. Method:Longitudinal analysis of linked cancer registrations, hospital separations and death registrations in Western Australia in 1990,98 using a population-based record linkage system. Results:There was an estimated total of 53,450 patients ever-diagnosed with cancer in Western Australia at 30 June 1998 (29.7 per 1,000 population), an increase of 51 % since mid-1990 (21.9/1,000). Patients with active disease accounted for 25% of the total prevalence, and the active prevalence of cancer increased from 5.1/1,000 in 1990 to 7.4/1,000 in 1998. In patients with active cancer, hospital admission rates for procedures other than chemotherapy and radiotherapy were stable or declining, but admission rates for chemotherapy and radiotherapy increased. The annual average cumulative length of stay decreased. Conclusions and implications:There has been a rapid increase in the number of prevalent patients requiring health care services for cancer during the 1990s. Most of the increase is due to improved survival, population growth and ageing. Further strain on Australian health care expenditure seems inevitable. [source] Methamphetamine-related Emergency Department Utilization and CostACADEMIC EMERGENCY MEDICINE, Issue 1 2008Robert G. Hendrickson MD Abstract Objective:, To quantify the frequency, cost, and characteristics associated with emergency department (ED) visits that are related to methamphetamine use. Methods:, This was a prospective observational study. The authors performed a training program for ED clinicians on the acute and chronic effects of methamphetamine and the signs of methamphetamine abuse. A standardized two question survey was administered to clinicians concerning the relationship between the ED visit and the patient's methamphetamine use. The survey was embedded in the patient tracking system and was required for all ED patients before disposition. Survey results were merged with administrative data on demographics, diagnosis, disposition, and charges. Univariate analyses were used to determine patient characteristics associated with methamphetamine-related ED visits. Results:, The authors examined 15,038 ED visits over a 20-week period from February 2006 to June 2006. There were a total of 353 methamphetamine-related visits, for an average of 17.65 visits per week (2.4% of all visits). Hospital charges for methamphetamine-related ED visits averaged $133,181 per week, for an estimated total of $6.9 M in annual charges. Methamphetamine-related ED patients were more likely to be male (odds ratio [OR] 1.6, 95% confidence interval [CI] = 1.30 to 2.01), white (OR 1.8, 95% CI = 1.38 to 2.29), and uninsured (OR 3.2, 95% CI = 2.21 to 4.69). The top four medical conditions associated with methamphetamine-related visits were mental health (18.7%), trauma (18.4%), skin infections (11.1%), and dental diagnoses (9.6%). Conclusions:, Methamphetamine abuse accounts for a modest but substantial proportion of ED utilization and hospital cost. Methamphetamine-related ED visits are most commonly related to mental illness, trauma, skin, and dental-related problems. [source] Within night correlations between radar and ground counts of migrating songbirdsJOURNAL OF FIELD ORNITHOLOGY, Issue 2 2008Michael L. Peckford ABSTRACT Studies comparing numbers of nocturnal migrants in flight with numbers of migrants at stopover sites have produced equivocal results. In 2003, we compared numbers of nocturnal migrants detected by radar to numbers of passerines observed at the Atlantic Bird Observatory in southwestern Nova Scotia, Canada. Numbers of nocturnal migrants detected by radar were positively correlated with numbers of migrants as determined by mist-netting, censuses, and daily estimated totals (daily estimates of birds present based netting and census results and casual observations) the following day. On nights with winds favorable for migration (tailwinds), the peak correlation between ground counts and radar counts the night before occurred just after sunset. On nights with unfavorable winds (headwinds), the correlation increased through the night, with a peak just before sunrise. The patterns of correlation are consistent with a scenario where birds accumulate at the coastline during periods of unfavorable wind, likely because they are not willing to cross a major ecological barrier, the Gulf of Maine. On nights with favorable winds, many birds departed, but some, possibly after testing wind conditions, apparently decided not to cross the Gulf of Maine and returned. Our results suggest that combining data collected using different methods to generate a daily estimated total provides the best estimate of the number of migrants present at a stopover site. Simultaneous studies at multiple locations where different census methods are used, making more effective use of temporal data (both from radar and diurnal counts), will more clearly elucidate patterns of flight behavior by migratory songbirds and the relationship between ground counts and counts of birds aloft. SINOPSIS Estudios cuales comparan los números de aves migratorias en vuelo durante la noche con los números de aves migratorias en sitios de reposo han producido resultados desiguales. En el 2003, comparamos los números de aves migratorias nocturnas detectadas por radar con los números de aves de Passeriformes observadas en el Atlantic Bird Observatory en el sudoeste de Nueva Escocia, Canadá. Los números de aves migratorias detectadas por radar fueron positivamente correlacionados con los números de aves migratorias detectadas mediante la captura con redes de neblina, por censos y por estimaciones diarias totales (el número de aves migratorias basado en capturas, censos y observaciones no-estandarizadas) durante el próximo día. En noches con vientos favorables para la migración (vientos de cola), el punto máximo de la correlación entre los conteos hechos en la tierra con los conteos hechas mediante radar durante la noche anterior ocurrió justo después de la puesta del sol. En noches con vientos no-favorables para la migración (vientos de frente), la correlación incrementó durante la noche, con un punto máximo justo antes del amanecer. Los patrones de las correlaciones son consistentes con una situación en la cual las aves se acumulan sobre la costa del mar durante periodos de viento no-favorables, probablemente porque no están dispuestos a cruzar una barrera ecológica de mayor tamaño, cual es el Golfo de Maine. En noches con vientos favorables, muchas aves partieron, pero algunos, posiblemente después de probar las condiciones de viento, aparentemente decidieron no cruzar el Golfo de Maine y retornaron. Nuestros resultados sugieren que una combinación de datos colectados utilizando diferentes métodos para generar una estimación diaria total provee la mejor estimación del número de aves migratorias presentes en un sitio de reposo. Estudios simultáneos hechos en múltiples sitios donde diferentes métodos de censo son utilizados, realizando un uso mas efectivo de los datos tomados a través del tiempo (provenientes de conteos mediante radar así como de observadores durante el día), mostrarán mas claramente cuales son los patrones del vuelo de las aves migratorias y la relación entre los conteos hechos en la tierra y los conteos de aves en alto vuelo. [source] | |||||||||||||