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1.
AIDS Behav ; 25(2): 592-603, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32886219

RESUMEN

There is a need for evidence-based contextualized mental health interventions for persons living with HIV/AIDS. In the current study, the primary researcher conducted open trials with African American women living with HIV/AIDS (AAWLWHA) to examine the acceptability and feasibility of Project UPLIFT, a mindfulness-based cognitive therapy intervention that has demonstrated effectiveness in persons living with epilepsy. Women were recruited for a tele-delivered phone intervention group separated by gender identity, as well as participated in pre- and post-test assessments. Additionally, data on acceptability was collected. Both cis- and transgender women were highly satisfied with the intervention and demonstrated improvement in depressive and stress symptoms. The intervention seemed to be particularly feasible for cisgender women, though more qualitative mental health research may be warranted with transgender women. The current research has implications for the utility of mindfulness-based interventions such as UPLIFT, with AAWLWHA.


Asunto(s)
Terapia Cognitivo-Conductual , Infecciones por VIH , Atención Plena , Personas Transgénero , Negro o Afroamericano , Femenino , Identidad de Género , Infecciones por VIH/terapia , Humanos , Masculino
2.
Agric Ecosyst Environ ; 283: 106572, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31680709

RESUMEN

There is currently much debate around the environmental implications of ruminant farming and a need for robust data on nitrogen (N) and carbon (C) fluxes from beef and sheep grazing systems. Here we use data collected from the North Wyke Farm Platform along with the SPACSYS model to examine the N and C budgets and the N use efficiency (NUE) of grassland swards at different stages of establishment. We assessed the transition from permanent pasture (PP) to a high-sugar grass (HSG), and a mixed sward of HSG with white clover (HSGC), identifying data specifically for the reseed (RS) years and the first year following RS (HSG-T and HSGC-T). Dominant fluxes for the N budget were N offtake as cut herbage and via livestock grazing, chemical-N fertiliser and N leaching at 88-280, 15-177, and 36-92 kg N ha-1 a-1, respectively. Net primary productivity, soil respiration and C offtake as cut herbage and via livestock grazing at 1.9-15.9, 1.74-12.5, and 0.34-11.7 t C ha-1 a-1, respectively, were the major C fluxes. No significant differences were found between the productivity of any of the swards apart from in the RS year of establishment. However, NUE of the livestock production system was significantly greater for the HSGC and HSGC-T swards at 32 and 42% compared to all other swards, associated with the low chemical-N fertiliser inputs to these clover-containing swards. Our findings demonstrate opportunities for improving NUE in grazing systems, but also the importance of setting realistic NUE targets for these systems to provide achievable goals for land-managers.

3.
J Environ Qual ; 44(4): 1216-24, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26437103

RESUMEN

Phosphorus (P) contributes to eutrophication of surface waters and buffer strips may be implemented to reduce its transfer from agricultural sources to watercourses. This study was conducted to test the hypothesis that soil type and slope influence the retention of dissolved organic P and inorganic orthophosphate in agricultural runoff in 2-m-wide buffer strip soils. A solution, comprised of dissolved orthophosphate and the organic P compounds glucose-1-phosphate, RNA, and inositol hexakisphosphate (1.8 mg L total P) and a chloride tracer, was applied as simulated overland flow to grassland soil blocks (2 m long × 0.5 m wide × 0.35 m deep), containing intact clay or loam soils, at slope angles of 2, 5, and 10°. Phosphorus forms were determined in the surface and subsurface flow from the soil blocks. Slope had no significant effect on the hydrological behavior of the soil blocks or on the retention of any form of P at the water application rate tested. The clay soil retained 60% of the unreactive P and 21% of the reactive P applied. The loam soil retained 74% of the unreactive P applied but was a net source of reactive P (the load increased by 61%). This indicates leaching of native soil P or hydrolysis of organic compounds and complicates our understanding of P retention in buffer strip soils. Our results suggest that a 2-m buffer strip may be more effective for reducing dissolved unreactive P transfers to surface waters than for reducing the eutrophication risk posed by dissolved reactive P.

4.
Sci Total Environ ; 648: 1179-1200, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30340264

RESUMEN

Diffuse water pollution from agriculture (DWPA) is a major environmental concern, with significant adverse impacts on both human and ecosystem health. However, without an appropriate understanding of the multiple factors impacting on water, mitigation measures cannot be targeted. Therefore, this paper addresses this gap in understanding, reporting the hydrochemical monitoring evidence collected from the UK Government's Demonstration Test Catchments (DTC) programme including contrasting chalk and clay/mudstone catchments. We use data collected at daily and sub-daily frequency over multiple sites to address: (1) How does the behaviour of the full range of nitrogen (N) species and phosphorus (P) fractions vary? (2) How do N species and P fractions vary inter- and intra-annually? (3) What do these data indicate about the primary pollution sources? And (4) which diffuse pollution mitigation measures are appropriate in our study landscapes? Key differences in the rates of flux of nutrients were identified, dependent on catchment characteristics. Full N speciation and P fractionation, together with dissolved organic carbon (DOC) enabled identification of the most likely contributing sources in each catchment. Nitrate (NO3-N) was the dominant N fraction in the chalk whereas organic and particulate N comprised the majority of the load in the clay/mudstone catchments. Despite current legislation, orthophosphate (PO4-P) was not found to be the dominant form of P in any of the catchments monitored. The chalk sub-catchments had the largest proportion of inorganic/dissolved organic P (DOP), accompanied by episodic delivery of particulate P (PP). Contrastingly, the clay/mudstone sub-catchments loads were dominated by PP and DOP. Thus, our results show that by monitoring both the inorganic and organic fractions a more complete picture of catchment nutrient fluxes can be determined, and sources of pollution pin-pointed. Ultimately, policy and management to bring nutrient impacts under control will only be successful if a multi-stressor approach is adopted.

5.
Environ Int ; 128: 362-370, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31078005

RESUMEN

Trapezoidal integration by linear interpolation of data points is by far the most commonly used method of cumulative flux calculations of nitrous oxide (N2O) in studies that use flux chambers; however, this method is incapable of providing accurate uncertainty estimates. A Bayesian approach was used to calculate N2O emission factors (EFs) and their associated uncertainties from flux chamber measurements made after the application of nitrogen fertilisers, in the form of ammonium nitrate (AN), urea (Ur) and urea treated with Agrotain® urease inhibitor (UI) at four grassland sites in the UK. The comparison between the cumulative fluxes estimated using the Bayesian and linear interpolation methods were broadly similar (R2 = 0.79); however, the Bayesian method was capable of providing realistic uncertainties when a limited number of data points is available. The study reports mean EF values (and 95% confidence intervals) of 0.60 ±â€¯0.63, 0.29 ±â€¯0.22 and 0.26 ±â€¯0.17% of applied N emitted as N2O for the AN, Ur and UI treatments, respectively. There was no significant difference between N2O emissions from the Ur and UI treatments. In the case of the automatic chamber data collected at one site in this study, the data did not fit the log-normal model, implying that more complex models may be needed, particularly for measurement data with high temporal resolution.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Fertilizantes/análisis , Nitrógeno/análisis , Óxido Nitroso/análisis , Teorema de Bayes , Inglaterra , Pradera , Escocia , Gales
8.
Aliment Pharmacol Ther ; 22(6): 539-45, 2005 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16167970

RESUMEN

BACKGROUND: The gastric juice concentration of vitamin C is reduced in subjects with elevated intragastric pH. This is probably because of the fact that the vitamin is unstable at non-acidic pH and undergoes irreversible denaturation. AIM: To determine whether elevation of intragastric pH reduces the bioavailability of dietary vitamin C. METHODS: Plasma vitamin C was measured before and after a course of omeprazole 40 mg/day for 4 weeks in 14 Helicobacter pylori positive and 15 H. pylori negative subjects. Dietary intake of vitamin C was measured and intragastric pH monitored. RESULTS: Compared with the H. pylori negative subjects, H. pylori positive subjects had a lower mean daily vitamin C intake (141.7 mg vs. 41.5 mg, P < 0.01) and also lower plasma vitamin C concentration (25.1 microg/mL vs. 17.4 microg/mL, P < 0.0001). After 28 days of 40 mg/day of omeprazole the mean plasma vitamin C level had fallen by 12.3% (P = 0.04). This fall affected both the H. pylori positive and negative subjects. CONCLUSIONS: We have shown that a short course of omeprazole will cause a reduction in the plasma vitamin C level of healthy volunteers. This decrease in plasma vitamin C is independent of dietary intake of the vitamin and indicates reduced bioavailability. The clinical significance of this is unclear but any adverse effects will be most apparent in H. pylori infected subjects who have a low pre-treatment vitamin C status.


Asunto(s)
Ácido Ascórbico/farmacocinética , Inhibidores Enzimáticos/efectos adversos , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Omeprazol/efectos adversos , Inhibidores de la Bomba de Protones , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/sangre , Disponibilidad Biológica , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Femenino , Ácido Gástrico/química , Humanos , Concentración de Iones de Hidrógeno , Masculino , Omeprazol/administración & dosificación , Omeprazol/farmacología
10.
Appl Opt ; 38(30): 6225-36, 1999 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-18324146

RESUMEN

An intercomparison of ozone differential absorption lidar algorithms was performed in 1996 within the framework of the Network for the Detection of Stratospheric Changes (NDSC) lidar working group. The objective of this research was mainly to test the differentiating techniques used by the various lidar teams involved in the NDSC for the calculation of the ozone number density from the lidar signals. The exercise consisted of processing synthetic lidar signals computed from simple Rayleigh scattering and three initial ozone profiles. Two of these profiles contained perturbations in the low and the high stratosphere to test the vertical resolution of the various algorithms. For the unperturbed profiles the results of the simulations show the correct behavior of the lidar processing methods in the low and the middle stratosphere with biases of less than 1% with respect to the initial profile to as high as 30 km in most cases. In the upper stratosphere, significant biases reaching 10% at 45 km for most of the algorithms are obtained. This bias is due to the decrease in the signal-to-noise ratio with altitude, which makes it necessary to increase the number of points of the derivative low-pass filter used for data processing. As a consequence the response of the various retrieval algorithms to perturbations in the ozone profile is much better in the lower stratosphere than in the higher range. These results show the necessity of limiting the vertical smoothing in the ozone lidar retrieval algorithm and questions the ability of current lidar systems to detect long-term ozone trends above 40 km. Otherwise the simulations show in general a correct estimation of the ozone profile random error and, as shown by the tests involving the perturbed ozone profiles, some inconsistency in the estimation of the vertical resolution among the lidar teams involved in this experiment.

11.
Seizure ; 5(3): 229-34, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8902926

RESUMEN

Tiagabine (TGB) and vigabatrin (VGB) are two novel anticonvulsant compounds reported to exert their pharmacological effects via an action on the gamma-aminobutyric acid (GABA) system. We have investigated the effects of acute exposure of these drugs on the uptake of GABA into rat cortical astrocytes in primary culture. Astrocytes were prepared from the cerebral cortices of one day-old rat pups by a mechanical dissociation technique and were assayed for GABA uptake activity after 21 days in culture. Tiagabine (100-300 nM) and VGB (100 microM) reduced GABA uptake when compared to control at four hours post-exposure. GABA uptake was also reduced following eight and 24 hour exposures to 200 nM TGB. A combination of TGB (200 nM) and VGB (100 microM) treatments reduced GABA uptake when compared to both control and VGB treated cultures. These results support the efficacy of TGB as a GABA uptake inhibitor and suggest that VGB may also exert an effect by this mechanism.


Asunto(s)
Anticonvulsivantes/farmacología , Astrocitos/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Inhibidores de la Captación de Neurotransmisores/farmacología , Ácidos Nipecóticos/farmacología , Ácido gamma-Aminobutírico/análogos & derivados , Ácido gamma-Aminobutírico/metabolismo , Animales , Animales Recién Nacidos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Tiagabina , Vigabatrin , Ácido gamma-Aminobutírico/farmacología
12.
Chemosphere ; 34(9-10): 1921-32, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9159894

RESUMEN

Since 1977 the Canadian Department of Fisheries and Oceans (DFO) has maintained a specimen bank for retrospective chemical analyses. The Great Lakes Fisheries Specimen Bank (GLFSB) is a complementary activity to the department's ongoing Great Lakes Contaminants Surveillance Program that has annually, since 1977, monitored levels of metals and organochlorines in aquatic biota throughout the Canadian Great Lakes. Past activities have focused on defining the effects of long-term frozen storage on the integrity of organochlorine residues in archived biological tissues. Archived samples have been reanalyzed for total PCBs, PCB congeners including co-planar PCBs, dioxin and furan isomers, and 22 toxaphene congeners. More recently, archived samples of predatory fish have been analyzed for stable isotopes of nitrogen (delta 15N) and carbon (delta 13C), as indicators of historical changes in food web dynamics. A catalogue or user-guide has recently been completed describing all information associated with samples stored in the GLFSB.


Asunto(s)
Bancos de Muestras Biológicas , Monitoreo del Ambiente/métodos , Explotaciones Pesqueras , Animales , Canadá , Great Lakes Region , Insecticidas/análisis , Bifenilos Policlorados/análisis , Manejo de Especímenes/métodos , Toxafeno/análisis , Contaminantes Químicos del Agua/análisis
13.
Chemosphere ; 40(9-11): 1221-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10739065

RESUMEN

Samples of a top predator fish species, lake trout (Salvelinus namaycush) and predominant forage species including smelt (Osmerus mordax), alewife (Alosa pseudoharengus), slimy sculpin (Cottus cognatus), deepwater sculpin (Myoxocephalus quadricornis) and lake herring (Coregonus artedii) were, collected from throughout 4 of the 5 Great Lakes (Superior, Huron, Erie and Ontario) (Fig. 1). Lake trout were also collected from three isolated lake systems (Lakes Nipigon, Simcoe and Opeongo), all located within the basin. All the samples were analysed for body burdens of total toxaphene and 22 toxaphene congeners. In addition, from each of the Great Lakes sites samples of major invertebrate dietary items, which included Mysis relicta, Diporeia hoyi and plankton, were similarly analysed. Whole lake trout samples, archived at -80 degrees C, were reanalysed to determine historical trends of toxaphene congeners plus carbon and nitrogen stable isotope signatures. The Lake Superior food web consistently had the highest levels of total toxaphene of all the Great Lakes monitored. The primary source of toxaphene to Lake Superior has been identified as atmospheric transport and deposition from sites in the southern US, Mexico and Central America (Hoff, R.M., Strachan, W.M.J., Sweet, C.W., Chan, C.H., Shackelton, M., Bidleman, T.F., Brice, K.A., Burnison, D.A., Cussion, S., Gatz, D.F., Harlin, K., Schroeder, W.H., 1996. Atmospheric deposition of toxic chemicals to the Great Lakes: A review of data through 1994. Atmospheric Environ. 30, 3505-3527). Of the offsystem lakes surveyed. Lake Nipigon, situated due north of Lake Superior and with a Lake Basin area of about 6% of Lake Superior (Hendendorf, C.E., 1982. J. Great Lakes Res. 8(3), 379-412) had total toxaphene levels in lake trout equivalent to about 50% of those found in lake trout from Lake Superior. Temporal trend toxaphene congener analysis was conducted on archived whole fish samples collected over the period 1980 through to the 1990's. Initially a nonachlorobornane congener (Parlar #50) was predominant, with congeners #40, #62 and #21 being the next most prominent in the 1980 samples. Samples from the 1990's showed a significant decline in the presence of lower chlorinated congeners #40 and #21. Analysis of total toxaphene in food webs, indicated elevated levels in lower trophic level species such as Diporeia and Cottus sp. which have a benthic association. The stable isotope temporal trend 13C signature identified a significant shift in the lake trout diet over the period 1993 to 1996.


Asunto(s)
Cadena Alimentaria , Insecticidas/análisis , Toxafeno/análisis , Contaminantes del Agua/análisis , Animales , Canadá , Peces/metabolismo , Insecticidas/metabolismo , Toxafeno/metabolismo , Contaminantes del Agua/metabolismo
14.
Clin Nurs Res ; 10(4): 347-63; discussion 364-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11881948

RESUMEN

Family caregiving within institutional settings is a neglected area of research In an era of cost containment, more and more is being asked of families of institutionalized persons. This article presents the results of a study designed to investigate family caregiving following the admission of an elderly relative to a long-term care facility. Beginning with a brief summary of findings from previous research, the article reports on visiting and task performance by families within the long-term care facility. Continuing with descriptions of families' satisfaction with institutional care and their care-related learning needs, the article concludes with recommendations for policy and practice.


Asunto(s)
Cuidadores , Familia , Cuidados a Largo Plazo/organización & administración , Casas de Salud/organización & administración , Comportamiento del Consumidor , Humanos , Ontario , Encuestas y Cuestionarios
15.
J Contin Educ Nurs ; 32(2): 68-76; quiz 94-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11868744

RESUMEN

The purpose of this study was to determine corporate philosophies of continuing education and approaches to meeting the learning needs of staff who strive to provide for the increasingly challenging care requirements of seniors who reside in long-term care facilities. In-depth interviews lasting approximately 1 hour were conducted with key informants at the administrative level from nine long-term care facilities. Content analysis revealed a commitment to continuing education for staff. While recognizing the importance of organizational responsibility for continuing education, administrators placed emphasis on the individual responsibility of staff. Learning needs were identified as affective, managerial, and physical in nature. Challenges to providing continuing education programs were derived from a general lack of fiscal and human resources. A variety of measures was suggested as important to supporting the continuing learning of staff. Implications of this study point to the need for long-term care facilities to incorporate into their strategic plans measures of ensuring continuing education as a basis for the ongoing competence and development of staff. In addition, there is a need for collaboration between long-term care facilities and other institutions of a long-term care, acute care, and educational nature in the development of strategies to operationalize a philosophy of continuing learning as a basis for the provision of optimal care to residents.


Asunto(s)
Actitud del Personal de Salud , Educación Continua en Enfermería/organización & administración , Administradores de Instituciones de Salud/psicología , Capacitación en Servicio/organización & administración , Personal de Enfermería/educación , Objetivos Organizacionales , Instituciones de Cuidados Especializados de Enfermería/organización & administración , Conocimientos, Actitudes y Práctica en Salud , Humanos , Modelos Educacionales , Evaluación de Necesidades , Investigación en Educación de Enfermería , Ontario , Cultura Organizacional , Política Organizacional , Encuestas y Cuestionarios , Recursos Humanos
16.
Can J Occup Ther ; 62(5): 242-9, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10152880

RESUMEN

A qualitative research project was undertaken to investigate the clinical utility of the Canadian Occupational Performance Measure (COPM) among therapists from the Regional Municipality of Ottawa-Carleton's Home Care Programme. Nineteen occupational therapists participated in one of four focus groups and in a plenary session to elicit reasons why some therapists used the COPM to assess clients and why others did not. The participants presented a wide range of opinions on the same theme, often from two polarities. The five themes that emerged from the focus groups and which were validated during the plenary session were: Use, environment, administration, outcome and suggested changes. The results demonstrated that COPM utility depended upon the degree to which therapists had incorporated the client-centred approach in their practice, the degree to which management valued and supported the use of the COPM and the degree to which the COPM could be flexible to fit practice context.


Asunto(s)
Terapia Ocupacional/normas , Atención Dirigida al Paciente/normas , Canadá , Recolección de Datos , Grupos Focales , Servicios de Atención de Salud a Domicilio/organización & administración , Servicios de Atención de Salud a Domicilio/normas , Terapia Ocupacional/educación , Evaluación de Resultado en la Atención de Salud , Guías de Práctica Clínica como Asunto , Recursos Humanos
17.
Can J Occup Ther ; 61(4): 191-7, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10137673

RESUMEN

The Canadian Occupational Performance Measure (COPM) is a measure of a client's self-perception of occupational performance in the areas of self-care, productivity and leisure. The COPM is administered using a semi-structured interview in which the client identifies significant issues in daily activities which are causing difficulty. Extensive pilot testing of the COPM has been completed with 268 clients in communities across Canada and in New Zealand, Greece and Britain. Results indicate the COPM has a median administration time of 30 minutes, is able to identify a wide range of occupational performance issues and appears to be responsive to changes in measurement issues centering around the interview, test construction, scoring, timing of the assessment, respondents, and the assessment process are discussed.


Asunto(s)
Actividades Cotidianas , Terapia Ocupacional/métodos , Participación del Paciente , Autoevaluación (Psicología) , Adolescente , Adulto , Anciano , Canadá , Niño , Preescolar , Femenino , Humanos , Entrevistas como Asunto/métodos , Masculino , Persona de Mediana Edad , Atención Dirigida al Paciente , Proyectos Piloto
18.
J Laryngol Otol ; 127(8): 773-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23866839

RESUMEN

OBJECTIVE: Voice rest is commonly recommended after vocal fold surgery, but there is a lack of evidence base and no standard protocol. The aim of this study was to establish common practice regarding voice rest following vocal fold surgery. METHOD: An online survey was circulated via e-mail invitation to members of the ENT UK Expert Panel between October and November 2011. RESULTS: The survey revealed that 86.5 per cent of respondents agreed that 'complete voice rest' means no sound production at all, but there was variability in how 'relative voice rest' was defined. There was no dominant type of voice rest routinely recommended after surgery for laryngeal papillomatosis or intermediate pathologies. There was considerable variability in the duration of voice rest recommended, with no statistically significant, most popular response (except for malignant lesions). Surgeons with less than 10 years of experience were more likely to recommend fewer days of voice rest. CONCLUSION: There is a lack of consistency in advice given to patients after vocal fold surgery, in terms of both type and length of voice rest. This may arise from an absence of robust evidence on which to base practice.


Asunto(s)
Cuidados Posoperatorios/métodos , Descanso/psicología , Pliegues Vocales/cirugía , Calidad de la Voz , Testimonio de Experto , Humanos , Neoplasias Laríngeas/cirugía , Laringoscopía , Papiloma/cirugía , Médicos/psicología , Cuidados Posoperatorios/normas , Descanso/fisiología , Semántica , Factores de Tiempo , Pliegues Vocales/fisiología , Trastornos de la Voz/rehabilitación , Trastornos de la Voz/cirugía
20.
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