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1.
Environ Sci Technol ; 51(15): 8324-8334, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28704046

RESUMO

Mountaintop removal coal mining (MTM) is a form of surface mining where ridges and mountain tops are removed with explosives to access underlying coal seams. The crushed rock material is subsequently deposited in headwater valley fills (VF). We examined how this added water storage potential affects streamflow using a paired watershed approach consisting of two sets of mined and unmined watersheds in West Virginia. The mined watersheds exported 7-11% more water than the reference watersheds, primarily due to higher and more sustained baseflows. The mined watersheds exported only ~1/3 of their streamflow during storms, while the reference watersheds exported ~2/3 of their annual water yield during runoff events. Mined watersheds with valley fills appear to store precipitation for considerable periods of time and steadily export this alkaline and saline water even during the dry periods of the year. As a result, MTMVFs in a mixed mined/unmined watershed contributed disproportionately to streamflow during baseflow periods (up to >90% of flow). Because MTMVFs have both elevated summer baseflows and continuously high concentrations of total dissolved solids, their regional impact on water quantity and quality will be most extreme and most widespread during low flow periods.


Assuntos
Minas de Carvão , Poluentes Químicos da Água , Região dos Apalaches , Qualidade da Água , West Virginia
2.
Environ Sci Technol ; 50(4): 2064-74, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26800154

RESUMO

Land use impacts are commonly quantified and compared using 2D maps, limiting the scale of their reported impacts to surface area estimates. Yet, nearly all land use involves disturbances below the land surface. Incorporating this third dimension into our estimates of land use impact is especially important when examining the impacts of mining. Mountaintop mining is the most common form of coal mining in the Central Appalachian ecoregion. Previous estimates suggest that active, reclaimed, or abandoned mountaintop mines cover ∼7% of Central Appalachia. While this is double the areal extent of development in the ecoregion (estimated to occupy <3% of the land area), the impacts are far more extensive than areal estimates alone can convey as the impacts of mines extend 10s to 100s of meters below the current land surface. Here, we provide the first estimates for the total volumetric and topographic disturbance associated with mining in an 11 500 km(2) region of southern West Virginia. We find that the cutting of ridges and filling of valleys has lowered the median slope of mined landscapes in the region by nearly 10 degrees while increasing their average elevation by 3 m as a result of expansive valley filling. We estimate that in southern West Virginia, more than 6.4km(3) of bedrock has been broken apart and deposited into 1544 headwater valley fills. We used NPDES monitoring datatsets available for 91 of these valley fills to explore whether fill characteristics could explain variation in the pH or selenium concentrations reported for streams draining these fills. We found that the volume of overburden in individual valley fills correlates with stream pH and selenium concentration, and suggest that a three-dimensional assessment of mountaintop mining impacts is necessary to predict both the severity and the longevity of the resulting environmental impacts.


Assuntos
Minas de Carvão/métodos , Qualidade da Água , Meio Ambiente , Monitoramento Ambiental/métodos , Concentração de Íons de Hidrogênio , Rios , Selênio/análise , Poluentes Químicos da Água/análise , West Virginia
3.
Appl Environ Microbiol ; 81(24): 8457-68, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26431971

RESUMO

Subalpine forest ecosystems influence global carbon cycling. However, little is known about the compositions of their soil microbial communities and how these may vary with soil environmental conditions. The goal of this study was to characterize the soil microbial communities in a subalpine forest watershed in central Montana (Stringer Creek Watershed within the Tenderfoot Creek Experimental Forest) and to investigate their relationships with environmental conditions and soil carbonaceous gases. As assessed by tagged Illumina sequencing of the 16S rRNA gene, community composition and structure differed significantly among three landscape positions: high upland zones (HUZ), low upland zones (LUZ), and riparian zones (RZ). Soil depth effects on phylogenetic diversity and ß-diversity varied across landscape positions, being more evident in RZ than in HUZ. Mantel tests revealed significant correlations between microbial community assembly patterns and the soil environmental factors tested (water content, temperature, oxygen, and pH) and soil carbonaceous gases (carbon dioxide concentration and efflux and methane concentration). With one exception, methanogens were detected only in RZ soils. In contrast, methanotrophs were detected in all three landscape positions. Type I methanotrophs dominated RZ soils, while type II methanotrophs dominated LUZ and HUZ soils. The relative abundances of methanotroph populations correlated positively with soil water content (R = 0.72, P < 0.001) and negatively with soil oxygen (R = -0.53, P = 0.008). Our results suggest the coherence of soil microbial communities within and differences in communities between landscape positions in a subalpine forested watershed that reflect historical and contemporary environmental conditions.


Assuntos
Archaea/metabolismo , Bactérias/metabolismo , Consórcios Microbianos/genética , Microbiologia do Solo , Microbiologia da Água , Archaea/genética , Archaea/isolamento & purificação , Bactérias/genética , Bactérias/isolamento & purificação , Sequência de Bases , Carbono/metabolismo , Dióxido de Carbono/metabolismo , DNA Arqueal/genética , DNA Bacteriano/genética , Ecossistema , Florestas , Metano/metabolismo , Dados de Sequência Molecular , Montana , Oxigênio/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Estados Unidos
4.
Water Resour Res ; 51(6): 4109-4136, 2015 06.
Artigo em Inglês | MEDLINE | ID: mdl-27642197

RESUMO

Ungauged headwater basins are an abundant part of the river network, but dominant influences on headwater hydrologic response remain difficult to predict. To address this gap, we investigated the ability of a physically based watershed model (the Distributed Hydrology-Soil-Vegetation Model) to represent controls on metrics of hydrologic partitioning across five adjacent headwater subcatchments. The five study subcatchments, located in Tenderfoot Creek Experimental Forest in central Montana, have similar climate but variable topography and vegetation distribution. This facilitated a comparative hydrology approach to interpret how parameters that influence partitioning, detected via global sensitivity analysis, differ across catchments. Model parameters were constrained a priori using existing regional information and expert knowledge. Influential parameters were compared to perceptions of catchment functioning and its variability across subcatchments. Despite between-catchment differences in topography and vegetation, hydrologic partitioning across all metrics and all subcatchments was sensitive to a similar subset of snow, vegetation, and soil parameters. Results also highlighted one subcatchment with low certainty in parameter sensitivity, indicating that the model poorly represented some complexities in this subcatchment likely because an important process is missing or poorly characterized in the mechanistic model. For use in other basins, this method can assess parameter sensitivities as a function of the specific ungauged system to which it is applied. Overall, this approach can be employed to identify dominant modeled controls on catchment response and their agreement with system understanding.

5.
Am J Clin Oncol ; 35(5): 504-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21297430

RESUMO

Prostate cancer is the most frequently diagnosed malignancy among UK men and accounts for 12% of male deaths. Androgen deprivation therapy (ADT) is commonly used as part of the treatment for prostate cancer. It is effective at suppressing prostate-specific antigen, stabilizing disease, alleviating symptoms in advanced disease, and potentially prolonging survival. However ADT, presumably at least in part owing to low testosterone levels is associated with insulin resistance, the development of metabolic syndrome plus increased overall and cardiovascular disease mortality. We have reviewed the relationship between prostate cancer, ADT, metabolic syndrome, type 2 diabetes, and cardiovascular disease. We have not reviewed other potential medical problems such as osteoporosis. We suggest that there should be a baseline assessment of patients' risk for cardiovascular disease before starting ADT. Consideration should be given to starting appropriate therapies including lifestyle advice, antihypertensive and lipid-lowering agents, insulin sensitizer, plus possibly aspirin. Having started ADT, the patients should have a regular (possibly annual) assessment of their cardiovascular risk factors.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Complicações do Diabetes/induzido quimicamente , Diabetes Mellitus Tipo 2/fisiopatologia , Síndrome Metabólica/induzido quimicamente , Obesidade/induzido quimicamente , Neoplasias da Próstata/tratamento farmacológico , Doenças Cardiovasculares/mortalidade , Complicações do Diabetes/mortalidade , Humanos , Masculino , Síndrome Metabólica/mortalidade , Obesidade/mortalidade , Neoplasias da Próstata/complicações , Medição de Risco , Fatores de Risco , Taxa de Sobrevida
6.
Environ Manage ; 42(5): 867-76, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18663519

RESUMO

The potential impacts of land use on large woody debris (LWD) were examined in Sourdough Creek Watershed, a rapidly growing area encompassing Bozeman, Montana, USA. We identified six land classes within a 250 m buffer extending on either side of Sourdough Creek and assessed aquatic habitat and geomorphologic variables within each class. All LWD pieces were counted, and we examined 14 other variables, including undercut bank, sinuosity, and substrate composition. LWD numbers were generally low and ranged from 0 to 8.2 pieces per 50 m of stream. Linear regression showed that LWD increased with distance from headwaters, riparian forest width, and sinuosity in four of the six land classes. Statistically significant differences between land classes for many aquatic habitat and geomorphologic variables indicated the impacts of different land uses on stream structure. We also found that practices such as active wood removal played a key role in LWD abundance. This finding suggests that managers should prioritize public education and outreach concerning the importance of in-stream wood, especially in mixed-use watersheds where wood is removed for either aesthetic reasons or to prevent stream flooding.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental , Rios , Abastecimento de Água , Animais , Agricultura Florestal , Geografia , Atividades Humanas , Montana , Análise de Regressão , Medição de Risco , Solo
7.
Nurs Times ; 100(12): 54-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15067914

RESUMO

People with cancer in the UK should have access to a full spectrum of services. The role of the clinical nurse specialist is an important part of this development. In the specialty of urology/oncology, this role is still a relatively new development although the incidence of urological malignancy readily compares with other site-specific cancers.


Assuntos
Auditoria de Enfermagem , Especialidades de Enfermagem , Neoplasias Urológicas/enfermagem , Instituições de Assistência Ambulatorial , Humanos , Oncologia , Papel do Profissional de Enfermagem , Satisfação do Paciente , Desenvolvimento de Programas , Urologia
8.
Urol Nurs ; 24(6): 475-82, 515, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15658733

RESUMO

INTRODUCTION: The impact of a urology oncology nurse specialist in the practice environment to assist with both pre and postoperative education needs of men undergoing genitourinary surgery for cancer was evaluated. OBJECTIVE: This study aimed to improve the preoperative process and teaching for men planning surgery for genitourinary cancers, including the delivery of pathology results. A secondary aim was to decrease the incidence of postoperative incontinence. METHODS: Male patients undergoing a radical prostatectomy were recruited. Patients who underwent surgery were evaluated both before and after the urology oncology nurse specialist role was established. Followup was via phone call interview and International Prostate Symptom Score questionnaire. RESULTS: Men who received the personalized education from the urology oncology nurse specialist had a higher return of continence postoperatively, as well as higher satisfaction scores with the outcome of their surgery, including higher quality of life scores. CONCLUSION: The urology oncology nurse specialist role had a significant impact on the postoperative incontinence rate and provided a missing patient education piece that improved the overall patient satisfaction rate with oncology-related care.


Assuntos
Enfermeiros Clínicos/organização & administração , Educação de Pacientes como Assunto/organização & administração , Prostatectomia/efeitos adversos , Incontinência Urinária/prevenção & controle , Seguimentos , Humanos , Incidência , Masculino , Papel do Profissional de Enfermagem , Auditoria de Enfermagem , Pesquisa em Avaliação de Enfermagem , Satisfação do Paciente , Assistência Perioperatória/enfermagem , Assistência Perioperatória/psicologia , Avaliação de Programas e Projetos de Saúde , Prostatectomia/enfermagem , Prostatectomia/psicologia , Qualidade de Vida , Índice de Gravidade de Doença , Inquéritos e Questionários , Gestão da Qualidade Total/organização & administração , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia , Urodinâmica
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