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1.
AIDS Behav ; 25(2): 592-603, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32886219

RESUMO

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.


Assuntos
Terapia Cognitivo-Comportamental , Infecções por HIV , Atenção Plena , Pessoas Transgênero , Negro ou Afro-Americano , Feminino , Identidade de Gênero , Infecções por HIV/terapia , Humanos , Masculino
2.
Agric Ecosyst Environ ; 283: 106572, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31680709

RESUMO

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.
Environ Int ; 128: 362-370, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31078005

RESUMO

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.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Fertilizantes/análise , Nitrogênio/análise , Óxido Nitroso/análise , Teorema de Bayes , Inglaterra , Pradaria , Escócia , País de Gales
4.
Sci Total Environ ; 648: 1179-1200, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30340264

RESUMO

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.
J Environ Qual ; 44(4): 1216-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26437103

RESUMO

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.

6.
J Laryngol Otol ; 127(8): 773-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23866839

RESUMO

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.


Assuntos
Cuidados Pós-Operatórios/métodos , Descanso/psicologia , Prega Vocal/cirurgia , Qualidade da Voz , Prova Pericial , Humanos , Neoplasias Laríngeas/cirurgia , Laringoscopia , Papiloma/cirurgia , Médicos/psicologia , Cuidados Pós-Operatórios/normas , Descanso/fisiologia , Semântica , Fatores de Tempo , Prega Vocal/fisiologia , Distúrbios da Voz/reabilitação , Distúrbios da Voz/cirurgia
10.
Science ; 325(5936): 58-61, 2009 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-19574383

RESUMO

The Phoenix mission investigated patterned ground and weather in the northern arctic region of Mars for 5 months starting 25 May 2008 (solar longitude between 76.5 degrees and 148 degrees ). A shallow ice table was uncovered by the robotic arm in the center and edge of a nearby polygon at depths of 5 to 18 centimeters. In late summer, snowfall and frost blanketed the surface at night; H(2)O ice and vapor constantly interacted with the soil. The soil was alkaline (pH = 7.7) and contained CaCO(3), aqueous minerals, and salts up to several weight percent in the indurated surface soil. Their formation likely required the presence of water.


Assuntos
Gelo , Marte , Água , Carbonato de Cálcio , Meio Ambiente Extraterreno , Concentração de Íons de Hidrogênio , Robótica , Astronave , Temperatura
11.
Science ; 325(5936): 68-70, 2009 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-19574386

RESUMO

The light detection and ranging instrument on the Phoenix mission observed water-ice clouds in the atmosphere of Mars that were similar to cirrus clouds on Earth. Fall streaks in the cloud structure traced the precipitation of ice crystals toward the ground. Measurements of atmospheric dust indicated that the planetary boundary layer (PBL) on Mars was well mixed, up to heights of around 4 kilometers, by the summer daytime turbulence and convection. The water-ice clouds were detected at the top of the PBL and near the ground each night in late summer after the air temperature started decreasing. The interpretation is that water vapor mixed upward by daytime turbulence and convection forms ice crystal clouds at night that precipitate back toward the surface.


Assuntos
Gelo , Marte , Vapor , Atmosfera , Meio Ambiente Extraterreno , Astronave , Temperatura , Fatores de Tempo
12.
J Laryngol Otol ; 123(8): 830-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19470190

RESUMO

OBJECTIVE: To determine the most effective local anaesthetic method for manipulation of nasal fractures, and to compare the efficacy of local anaesthesia with that of general anaesthesia. METHOD: Systematic review and meta-analysis. DATABASES: Medline, Embase, Cochrane Library, National Research Register and metaRegister of Controlled Trials. INCLUDED STUDIES: We included randomised, controlled trials comparing general anaesthesia with local anaesthesia or comparing different local anaesthetic techniques. Non-randomised studies were also systematically reviewed and appraised. No language restrictions were applied. RESULTS: Five randomised, controlled trials were included, three comparing general anaesthesia versus local anaesthesia and two comparing different local anaesthetic methods. No significant differences were found between local anaesthesia and general anaesthesia as regards pain, cosmesis or nasal patency. The least painful local anaesthetic method was topical tetracaine gel applied to the nasal dorsum together with topical intranasal cocaine solution. Minimal adverse events were reported with local anaesthesia. CONCLUSIONS: Local anaesthesia appears to be a safe and effective alternative to general anaesthesia for pain relief during nasal fracture manipulation, with no evidence of inferior outcomes. The least uncomfortable local anaesthetic method included topical tetracaine gel.


Assuntos
Anestesia Geral/métodos , Anestesia Local/métodos , Manipulação Ortopédica/métodos , Osso Nasal/lesões , Obstrução Nasal/terapia , Fraturas Ósseas/cirurgia , Humanos , Dor/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Aliment Pharmacol Ther ; 22(6): 539-45, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16167970

RESUMO

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.


Assuntos
Ácido Ascórbico/farmacocinética , Inibidores Enzimáticos/efeitos adversos , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Omeprazol/efeitos adversos , Inibidores da Bomba de Prótons , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Disponibilidade Biológica , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Feminino , Ácido Gástrico/química , Humanos , Concentração de Íons de Hidrogênio , Masculino , Omeprazol/administração & dosagem , Omeprazol/farmacologia
14.
Scand J Gastroenterol ; 37(3): 253-61, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11916186

RESUMO

BACKGROUND: Dietary nitrate increases saliva nitrite levels and swallowed saliva is the main source of nitrite entering the acidic stomach. In acidic gastric juice, this nitrite can generate potentially carcinogenic N-nitrosocompounds. However, ascorbic acid secreted by the gastric mucosa can prevent nitrosation by converting the nitrite to nitric oxide. METHODS: To study the potential for N-nitrosocompound formation in a model simulating salivary nitrite entering the acidic stomach and the ability of ascorbic acid to inhibit the process. Concentrations of ascorbic acid, total vitamin C, nitrite, nitrosomorpholine, oxygen and nitric oxide were monitored during the experiments. RESULTS: The delivery of nitrite into HCl containing thiocyanate resulted in nitrosation of morpholine, with the rate of nitrosation being greatest at pH 2.5. Under anaerobic conditions, ascorbic acid converted the nitrite to nitric oxide and prevented nitrosation. However, in the presence of dissolved air, the ascorbic acid was ineffective at preventing nitrosation. This was due to the nitric oxide combining with oxygen to reform nitrite and this recycling of nitrite depleting the available ascorbic acid. Further studies indicated that the rate of consumption of ascorbic acid by nitrite added to natural human gastric juice (pH 1.5) was extremely rapid with 200 micromol/l nitrite consumed 500 micromol/l ascorbic acid within 10 s. CONCLUSIONS: The rapid consumption of ascorbic acid in acidic gastric juice by nitrite in swallowed saliva indicates that the potential for acid nitrosation will be maximal at the GO junction and cardia where nitrite first encounters acidic gastric juice. The high incidence of mutagenesis and neoplasia at this anatomical location may be due to acid nitrosation arising from dietary nitrate.


Assuntos
Junção Esofagogástrica/efeitos dos fármacos , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Ácido Ascórbico/farmacologia , Cárdia/efeitos dos fármacos , Cárdia/fisiopatologia , Suplementos Nutricionais , Interações Medicamentosas , Junção Esofagogástrica/metabolismo , Ácido Gástrico/metabolismo , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Modelos Anatômicos , Nitratos/farmacologia , Nitritos/farmacologia , Compostos Nitrosos/metabolismo , Saliva/química , Sensibilidade e Especificidade , Relação Estrutura-Atividade
15.
J Adv Nurs ; 35(3): 442-51, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11489030

RESUMO

BACKGROUND: Musculoskeletal pain is a problem with which many seniors must contend, many on a daily basis. Little is known, however, of the self-care decisions that seniors make regarding the management and control of this pain. These decisions can influence in a significant manner the delivery of health care to seniors and their overall health and well-being. Purpose. The purpose of our exploratory-descriptive study was to investigate seniors' decision making regarding the management and control of musculoskeletal pain by gathering data about the context of decision making, the types of decisions seniors made, their decisional conflict and the resources they used in decision making. METHODS: Focus groups and a mail-back questionnaire were used. Data were gathered in 1997 from a convenience sample of 50 seniors in Canada who experienced musculoskeletal pain of a noteworthy nature. RESULTS: Findings revealed that participants made decisions within a context of ageing and the health and social consequences of advancing age. The types of decisions they made included to ignore their pain and to use distraction. They also used exercise, the application of heat and cold, and medications to manage pain. Decisional conflict was minimal and consultation with family and friends superseded that with professionals. CONCLUSIONS: This study contributed to knowledge of decision making in later life about health matters generally, and the management and control of pain specifically. Findings point to the resourcefulness of seniors with respect to self-care and decision making. Seniors want to make informed decisions. However, they need information about the risks and benefits of decisions.


Assuntos
Idoso/psicologia , Atitude Frente a Saúde , Tomada de Decisões , Dor/prevenção & controle , Dor/psicologia , Autocuidado/psicologia , Idoso de 80 Anos ou mais , Analgésicos/uso terapêutico , Conflito Psicológico , Crioterapia , Exercício Físico , Feminino , Grupos Focais , Temperatura Alta/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Pesquisa Metodológica em Enfermagem , Educação de Pacientes como Assunto , Autocuidado/métodos , Inquéritos e Questionários
16.
J Contin Educ Nurs ; 32(2): 68-76; quiz 94-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11868744

RESUMO

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.


Assuntos
Atitude do Pessoal de Saúde , Educação Continuada em Enfermagem/organização & administração , Administradores de Instituições de Saúde/psicologia , Capacitação em Serviço/organização & administração , Recursos Humanos de Enfermagem/educação , Objetivos Organizacionais , Instituições de Cuidados Especializados de Enfermagem/organização & administração , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Modelos Educacionais , Avaliação das Necessidades , Pesquisa em Educação em Enfermagem , Ontário , Cultura Organizacional , Política Organizacional , Inquéritos e Questionários , Recursos Humanos
17.
Clin Nurs Res ; 10(4): 347-63; discussion 364-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11881948

RESUMO

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.


Assuntos
Cuidadores , Família , Assistência de Longa Duração/organização & administração , Casas de Saúde/organização & administração , Comportamento do Consumidor , Humanos , Ontário , Inquéritos e Questionários
18.
Gastroenterology ; 119(2): 339-47, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10930369

RESUMO

BACKGROUND & AIMS: Omeprazole produces greater acid inhibition in Helicobacter pylori-positive than -negative subjects. We investigated whether this is accompanied by more profound changes in the intragastric milieu that facilitates bacterial synthesis of N-nitroso compounds. METHODS: Gastric juice pH; nitrite, ascorbic acid, and total vitamin C concentrations; and colonization by other bacteria were examined before and during omeprazole treatment in subjects with and without H. pylori infection. Studies were performed in the fasting state and after consumption of 2 mmol nitrate (equivalent to a salad meal). RESULTS: Before omeprazole, H. pylori-positive and -negative subjects were similar for all parameters. During omeprazole, H. pylori-positive subjects had a higher intragastric pH (7.8 vs. 3.0; P < 0.00001) and greater colonization with non-H. pylori species (5 x 10(7) vs. 5 x 10(5) CFU/mL; P < 0.05). These bacteria included nitrosating species. During omeprazole treatment, H. pylori-positive subjects had higher intragastric nitrite levels after the nitrate meal (median area under the concentration/time curve, 12,450 vs. 4708 micromol/L. min; P = 0.04). Omeprazole lowered intragastric vitamin C levels in H. pylori-positive but not -negative subjects (1.8 vs. 3.4 microg/mL, respectively; P = 0.02). CONCLUSIONS: In H. pylori-positive subjects, omeprazole produces disturbances in intragastric nitrite, vitamin C, and bacterial colonization that facilitate bacterial N-nitrosation. This may place them at increased risk of mutagenesis and carcinogenesis.


Assuntos
Antiulcerosos/administração & dosagem , Gastrite/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/metabolismo , Omeprazol/administração & dosagem , Adulto , Ácido Ascórbico/análise , Ácido Ascórbico/sangue , Feminino , Suco Gástrico/química , Suco Gástrico/microbiologia , Gastrite/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Masculino , Técnicas Microbiológicas , Pessoa de Meia-Idade , Nitritos/análise , Nitrosação/efeitos dos fármacos , Saliva/química
19.
Chemosphere ; 40(9-11): 1221-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10739065

RESUMO

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.


Assuntos
Cadeia Alimentar , Inseticidas/análise , Toxafeno/análise , Poluentes da Água/análise , Animais , Canadá , Peixes/metabolismo , Inseticidas/metabolismo , Toxafeno/metabolismo , Poluentes da Água/metabolismo
20.
Pediatr Phys Ther ; 12(4): 158-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-17091027

RESUMO

Children with motor coordination problems often have difficulty succeeding in the classroom. No previous research could be located in which classroom teachers used screening tools to determine the severity of the children's motor coordination problems or their need for consultation from occupational and physical therapists. The purposes of this study were: 1) to examine the relationship between teachers' scores on the Movement Assessment Battery for Children (MABC) checklist and the physical therapist's scores on the MABC test; and 2) to examine the degree of concordance in decision making by determining if the teachers and physical therapist, using these two measures independently, identified the same children with motor difficulties and those without motor difficulties. Teachers completed the MABC checklist and the physical therapist administered the MABC test to 103 children. The relationship between the teachers' and physical therapist's scores was examined using the Pearson product-moment correlation. Sensitivity and specificity of the checklist were assessed with the MABC test scores as the criterion measure. The correlation between the teachers' scores and the physical therapist's scores was r = 0.51. The sensitivity of the checklist at the 15th percentile cutoff point was 14.3%, and specificity was 97.8%. The sensitivity of the MABC checklist was so low that many children at risk for motor problems based on the MABC test were not identified. Thus, the independent use of this checklist by teachers to identify children with motor coordination problems is not recommended.

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