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1.
Radiat Prot Dosimetry ; 199(15-16): 1685-1688, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819355

RESUMO

A High Purity Germanium (HPGe) detector has been used to measure the photon spectra in the majority of monoenergetic neutron fields produced at NPL (0.144, 0.250, 0.565, 2.0, 5.0 and 16.5 MeV). The HPGe was characterised and then modelled to produce a response matrix. The measured pulse height spectra were then unfolded to produce photon fluence spectra. The new spectra were used to improve the photon to neutron dose equivalent ratios from some earlier work at NPL with Geiger-Muller tubes and electronic personal dosemeters.


Assuntos
Nêutrons , Radiometria , Doses de Radiação , Fótons , Calibragem
2.
Braz. j. biol ; 82: e243250, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278502

RESUMO

The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as 'other' were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.


O Punjab urial (Ovis vignei punjabiensis) é uma espécie de ovelha selvagem ameaçada globalmente. No Paquistão, a espécie é legalmente protegida e criada em cativeiro para ser liberada em habitats para reforçar as populações selvagens. Vigilância e alimentação são essenciais para a sobrevivência, embora o grau de comportamento que os animais criados em cativeiro apresenta raramente tenha sido estudado. Cinco uriais adultos foram monitorados diariamente, após a liberação os comportamentos foram classificados das 6 h às 18 h, replicando cada período de uma hora por duas vezes e registrando quatro observações de cada animal por hora. Em nível do rebanho, os comportamentos de vigilância e alimentação foram exibidos igualmente. Machos e fêmeas investiam tempo igual na alimentação, enquanto os machos eram mais vigilantes (p = 0,001) e mais agressivos (p = 0,010), as fêmeas eram mais repousantes (p = 0,019) ou mais engajadas no asseio (p = 0,044) ou na locomoção (p = 0,002). As fêmeas passam mais tempo se alimentando do que vigiando (p = 0,002). Os machos mantiveram altos níveis de vigilância ao longo do dia. Padrões de descanso de 1300 a 1500 horas e alimentação no início da manhã e no final da tarde eram comuns para ambos os sexos. Comportamentos classificados como "outros" foram exibidos igualmente entre os sexos. Os resultados revelam indicações positivas na detecção de ameaça em relação ao equilíbrio de criação urial em cativeiro e em aquisição de energia pósliberação, exibindo comportamentos naturais e padrões de atividade. Neste estudo, encorajou-se a utilização da avaliação de sobrevivência para avaliar a eficácia em longo prazo da reprodução em cativeiro e soltura como um programa de restauração dos candidatos.


Assuntos
Animais , Masculino , Feminino , Ecossistema , Carneiro Doméstico , Paquistão , Ovinos
3.
Braz. j. biol ; 82: 1-7, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468531

RESUMO

The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as 'other' were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.


O Punjab urial (Ovis vignei punjabiensis) é uma espécie de ovelha selvagem ameaçada globalmente. No Paquistão, a espécie é legalmente protegida e criada em cativeiro para ser liberada em habitats para reforçar as populações selvagens. Vigilância e alimentação são essenciais para a sobrevivência, embora o grau de comportamento que os animais criados em cativeiro apresenta raramente tenha sido estudado. Cinco uriais adultos foram monitorados diariamente, após a liberação os comportamentos foram classificados das 6 h às 18 h, replicando cada período de uma hora por duas vezes e registrando quatro observações de cada animal por hora. Em nível do rebanho, os comportamentos de vigilância e alimentação foram exibidos igualmente. Machos e fêmeas investiam tempo igual na alimentação, enquanto os machos eram mais vigilantes (p = 0,001) e mais agressivos (p = 0,010), as fêmeas eram mais repousantes (p = 0,019) ou mais engajadas no asseio (p = 0,044) ou na locomoção (p = 0,002). As fêmeas passam mais tempo se alimentando do que vigiando (p = 0,002). Os machos mantiveram altos níveis de vigilância ao longo do dia. Padrões de descanso de 1300 a 1500 horas e alimentação no início da manhã e no final da tarde eram comuns para ambos os sexos. Comportamentos classificados como "outros" foram exibidos igualmente entre os sexos. Os resultados revelam indicações positivas na detecção de ameaça em relação ao equilíbrio de criação urial em cativeiro e em aquisição de energia pós liberação, exibindo comportamentos naturais e padrões de atividade. Neste estudo, encorajou-se a utilização da avaliação de sobrevivência para avaliar a eficácia em longo prazo da reprodução em cativeiro e soltura como um programa de restauração dos candidatos.


Assuntos
Animais , Comportamento Alimentar , Comportamento Animal , Ovinos , Vigilância em Desastres
4.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468718

RESUMO

Abstract The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as other were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.


Resumo O Punjab urial (Ovis vignei punjabiensis) é uma espécie de ovelha selvagem ameaçada globalmente. No Paquistão, a espécie é legalmente protegida e criada em cativeiro para ser liberada em habitats para reforçar as populações selvagens. Vigilância e alimentação são essenciais para a sobrevivência, embora o grau de comportamento que os animais criados em cativeiro apresenta raramente tenha sido estudado. Cinco uriais adultos foram monitorados diariamente, após a liberação os comportamentos foram classificados das 6 h às 18 h, replicando cada período de uma hora por duas vezes e registrando quatro observações de cada animal por hora. Em nível do rebanho, os comportamentos de vigilância e alimentação foram exibidos igualmente. Machos e fêmeas investiam tempo igual na alimentação, enquanto os machos eram mais vigilantes (p = 0,001) e mais agressivos (p = 0,010), as fêmeas eram mais repousantes (p = 0,019) ou mais engajadas no asseio (p = 0,044) ou na locomoção (p = 0,002). As fêmeas passam mais tempo se alimentando do que vigiando (p = 0,002). Os machos mantiveram altos níveis de vigilância ao longo do dia. Padrões de descanso de 1300 a 1500 horas e alimentação no início da manhã e no final da tarde eram comuns para ambos os sexos. Comportamentos classificados como outros foram exibidos igualmente entre os sexos. Os resultados revelam indicações positivas na detecção de ameaça em relação ao equilíbrio de criação urial em cativeiro e em aquisição de energia pós-liberação, exibindo comportamentos naturais e padrões de atividade. Neste estudo, encorajou-se a utilização da avaliação de sobrevivência para avaliar a eficácia em longo prazo da reprodução em cativeiro e soltura como um programa de restauração dos candidatos.

5.
Appetite ; 167: 105610, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34324909

RESUMO

The Reflective-Impulsive Dual Processes Model suggests that overeating occurs when the temptation to consume food overrides inhibitory control processes. However, how rewards interact with inhibitory control and their relation to children's weight status and food intake is not understood. Here, 7-to-11-year-old children (n = 66; 32 overweight/obese) completed two versions (baseline [i.e., non-reward incentivized/control] and reward incentivized [food, money, no reward]) of a Go/Nogo task. Intake of palatable foods in the absence of hunger (i.e., eating in the absence of hunger-EAH) was measured following a standardized meal. A drift diffusion model was used to characterize children's performance parameters on the Go/Nogo. On the baseline Go/Nogo, children with higher weight status responded more cautiously, but on reward trials for food/money children were more cautions and made more false alarms relative to the no reward condition. Energy intake during EAH positively correlated with FA errors for food and money vs. no reward, but sex moderated this effect such that FA positively associated with EAH in girls but not boys. Independent of sex, FA for money vs. no reward and food vs. money were both positively associated with energy consumed during EAH. These results suggest that the presence of food and money rewards impair inhibitory control processing, especially in children with higher weight status. Further, increased inhibitory control impairment in response to food rewards, specifically, may be a risk factor for disinhibited eating in girls. Though preliminary, results may be useful in the development of targeted treatments to help moderate excess consumption in children.


Assuntos
Comportamento Alimentar , Fome , Criança , Ingestão de Alimentos , Feminino , Humanos , Hiperfagia , Refeições , Recompensa
6.
Braz J Biol ; 82: e243250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133572

RESUMO

The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as 'other' were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.


Assuntos
Ecossistema , Carneiro Doméstico , Animais , Feminino , Masculino , Paquistão , Ovinos
7.
Respir Med ; 176: 106219, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33248362

RESUMO

BACKGROUND: The delivery of healthcare during the COVID pandemic has had a significant impact on front line staff. Nurses who work with respiratory patients have been at the forefront of the pandemic response. Lessons can be learnt from these nurses' experiences in order to support these nurses during the existing pandemic and retain and mobilise this skilled workforce for future pandemics. METHODS: This study explores UK nurses' experiences of working in a respiratory environment during the COVID-19 pandemic. An e-survey was distributed via professional respiratory societies; the survey included a resilience scale, the GAD7 (anxiety) and the PHQ9 (depression) tools. Demographic data was collected on age, gender, ethnicity, nursing experience and background, clinical role in the pandemic, and home-life and work balance. RESULTS: Two hundred and fifty-five responses were received for the survey, predominately women (89%, 226/255), aged over 35 (79%, 202/255). Nearly 21% (40/191) experiencing moderate to severe or severe symptoms of anxiety. Similar levels are seen for depression (17.2%, 31/181). 18.9% (34/180) had a low or very low resilience score. Regression analysis showed that for both depression and anxiety variables, age and years of qualification provided the best model fit. Younger nurses with less experience have higher levels of anxiety and depression and had lower resilience. CONCLUSION: This cohort experienced significant levels of anxiety and depression, with moderate to high levels of resilience. Support mechanisms and interventions need to be put in place to support all nurses during pandemic outbreaks, particularly younger or less experienced staff.


Assuntos
Ansiedade/epidemiologia , COVID-19/terapia , Depressão/epidemiologia , Recursos Humanos de Enfermagem/psicologia , Resiliência Psicológica , Terapia Respiratória , Adulto , Fatores Etários , COVID-19/psicologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Reino Unido , Adulto Jovem
8.
Sci Rep ; 10(1): 1486, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001726

RESUMO

The identification of corrosion, cracks and defects in pipelines used for transporting oil and gas can reduce the possibility of leaks, and consequently, it can limit the extent of an environmental disaster, public hazard and the associated financial impact of such events. Typically, corrosion in oil pipelines is measured with non-destructive ultrasonic or electromagnetic techniques, on the basis that corrosion and defects are often manifest as a change of thickness in the steel from which pipelines are made. However, such approaches are not practical for underground pipelines and their deployment can be complicated for the case of pipelines covered by insulation. In this paper, we present an innovative, non-destructive testing technique, which exploits the backscatter of a combination of fast-neutron and γ radiation from steel samples of a variety of thicknesses consistent with changes that might arise due to corrosion of a pipe wall. Our research demonstrates the potential to measure and characterise different steel thicknesses by detecting both the elastic, fast-neutron backscatter and the Compton-scattered γ radiations, simultaneously. Further, we demonstrate that the presence of insulation yields a consistent and separable influence on the experimental, wall-thickness measurements. The data from experimental measurements are supported by a comprehensive Monte Carlo computer simulation study.

9.
J Dairy Sci ; 103(3): 2405-2418, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31954581

RESUMO

We previously generated a high-metabolizable energy (HME) perennial ryegrass (Lolium perenne) by genetically modifying the plant to increase the leaf lipid content. Although substantial progress has been made toward characterizing physiological changes of HME ryegrass, very limited information exists for feeding value and its suitability for adoption into the pastoral system. In this study, independent HME ryegrass lines with a range of elevated leaf lipid concentrations were analyzed for changes in fatty acids and possible associated changes in the broader nutritional profile, including the gross energy, which was found to increase by 6.8%. Because ryegrass is often ensiled and fermentation in the rumen leads to biohydrogenation of fatty acids as well as enteric methane production, we sought to investigate these effects on HME ryegrass. This was achieved by performing mini-scale silos and using an automated gas measurement system to incubate the material in rumen fluid in vitro for 24 h. Our study included treatments comprising 3 independent HME ryegrass genotypes and wild-type control materials prepared fresh and as silage, employing in total 5 incubation studies, using rumen fluids collected from 4 nonlactating Jersey × Holstein cows. At intervals during the incubation, the production of gases, volatile fatty acids, and the degree of biohydrogenation were measured. Statistical data analysis indicated that differences in the nutritional compositions of the ensiled materials largely reflected those of their fresh counterparts. Incubation of both fresh and ensiled HME ryegrass in rumen fluid resulted in: (1) a greater percentage of valuable unsaturated fatty acids compared with the control; (2) a significant reduction of butyrate; and (3) a 10 to 15% decrease in the methane proportion of the total gas production. We conclude that ensiling could be a convenient option for preserving HME as a locally produced high-value supplementary feed; however, large-scale application needs to be investigated. In this paper we discuss the potential use of HME ryegrass to enhancing forage feeding value and the potential environmental benefits to the pastoral agriculture industry.


Assuntos
Bovinos/metabolismo , Lolium/metabolismo , Metano/biossíntese , Rúmen/metabolismo , Silagem , Animais , Butiratos/metabolismo , Digestão , Metabolismo Energético , Ácidos Graxos Voláteis/metabolismo , Feminino , Fermentação , Lolium/genética , Plantas Geneticamente Modificadas
10.
J Hosp Infect ; 101(1): 100-108, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30098382

RESUMO

BACKGROUND: To reduce the risk of transmission of meticillin-resistant Staphylococcus aureus (MRSA), international guidelines recommend admission screening to identify hospital patients at risk of colonization. However, routine monitoring indicates that optimum screening compliance levels are not always achieved. In order to enhance compliance, we must better understand those factors which influence staff screening behaviours. AIM: To identify factors which influence staff compliance with hospital MRSA screening policies. METHODS: A sequential two-stage mixed-methods design applied constructs from normalization process theory and the theoretical domains framework to guide data collection and analysis. Initial qualitative findings informed subsequent development of a national cross-sectional survey of nursing staff (N = 450). Multiple regression modelling identified which barriers and enablers best predict staff compliance. FINDINGS: Three factors were significant in predicting optimum (>90%) compliance with MRSA screening: having MRSA screening routinized within the admission process; category of clinical area; feedback of MRSA screening compliance within the clinical area. Integration of data-sets indicated that organizational systems which 'make doing the right thing easy' influence compliance, as does local ward culture. Embedded values and beliefs regarding the relative (de)prioritization of MRSA screening are important. CONCLUSION: To our knowledge, this is the first study to provide original evidence of barriers and enablers to MRSA screening, applying both sociological and psychological theory. As antimicrobial resistance is a global health concern, these findings have international relevance for screening programmes. Future policy recommendations or behaviour change interventions, based on the insights presented here, could have significant impact upon improving screening compliance.


Assuntos
Testes Diagnósticos de Rotina/métodos , Transmissão de Doença Infecciosa/prevenção & controle , Fidelidade a Diretrizes , Programas de Rastreamento/métodos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/diagnóstico , Estudos Transversais , Hospitais , Humanos
11.
Pediatr Obes ; 14(2): e12469, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30239165

RESUMO

BACKGROUND: Brain responses to both food and monetary rewards have been linked to weight gain and obesity in adults, suggesting that general sensitivity to reward contributes to overeating. However, the relationship between brain reward response and body weight in children is unclear. OBJECTIVE: The objective of this study was to assess the brain's response to multiple rewards and the relationship to body weight in children. METHODS: We tested this by performing functional magnetic resonance imaging while children (7- to 11-years-old; healthy weight [n = 31], overweight/obese [n = 30]) played a modified card-guessing task to assess blood-oxygen-level-dependent (BOLD) response to anticipating and winning food and money rewards. Functional magnetic resonance imaging data were analysed using a region of interest and exploratory whole-brain approach. RESULTS: Region of interest results demonstrated increased BOLD response in the striatum to anticipating food vs. neutral (control) and winning money vs. neutral. Whole-brain data showed that winning money vs. food was associated with increased activation in the striatum, as well as regions associated with cognitive control and emotion. Notably, for both approaches, these effects were independent of child weight status. Additionally, children's reported food responsiveness and emotional overeating were negatively correlated with the BOLD response in the left cingulate gyrus for winning food vs. money. CONCLUSION: Overall, findings from this study show that regions associated with reward, cognitive control and emotion may play a role in the brain's response to food and money rewards, independently of how much the child weighs. These findings provide insight into reward sensitivity in children, which may have implications for understanding overeating and the development of obesity.


Assuntos
Peso Corporal/fisiologia , Encéfalo/fisiopatologia , Comportamento Alimentar/fisiologia , Imageamento por Ressonância Magnética/métodos , Obesidade Pediátrica/fisiopatologia , Encéfalo/diagnóstico por imagem , Criança , Feminino , Alimentos , Humanos , Masculino , Recompensa , Inquéritos e Questionários
12.
Respir Med ; 145: 161-181, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30509706

RESUMO

INTRODUCTION: Pulmonary rehabilitation (PR) is a core component of Chronic Obstructive Pulmonary Disease (COPD) management with well recognized benefits. While suggestions for educational content within pulmonary rehabilitation have been detailed in clinical guidance, it is unclear what educational content is delivered as part of pulmonary rehabilitation, who delivers it, and how it is delivered. METHODS: A systematic review was conducted to identify what educational content is delivered as part of pulmonary rehabilitation, how is this delivered and who delivers it. Databases were searched from 1981 to 2017 using multiple search terms related to "pulmonary rehabilitation" and "education". RESULTS: Fourteen studies were identified. This included 6 survey studies, 5 quasi-experimental studies and 3 RCTs. Five key topics that were consistently included within PR programmes were identified as: 1) Anxiety/depression and stress management. 2) Early recognition of signs of infection. 3) Dyspnea and symptom management. 4) Nutrition. 5) Techniques using inhalers and nebulizers. Broader topics such as welfare/benefits, sexuality, and advance care directives did not frequently feature. Only four studies used tools to measure knowledge or learning pre and post rehabilitation in an attempt to evaluate the effectiveness of the education delivered as part of PR. CONCLUSIONS: The delivery of education in PR programmes is variable and does not follow suggested educational topics. Education needs to take a patient centered motivational approach to ensure effective delivery. Further research into appropriate educational outcome measures are needed, in order to evaluate the changes in behaviour associated with education.


Assuntos
Atenção à Saúde/métodos , Educação em Saúde/métodos , Doença Pulmonar Obstrutiva Crônica/reabilitação , Bases de Dados Bibliográficas , Gerenciamento Clínico , Comportamentos Relacionados com a Saúde , Humanos , Motivação , Assistência Centrada no Paciente , Doença Pulmonar Obstrutiva Crônica/psicologia
13.
Radiat Prot Dosimetry ; 180(1-4): 25-28, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29040724

RESUMO

As part of its wide-ranging neutron metrology capabilities, the National Physical Laboratory in the UK has a thermal neutron facility in which accelerator-produced neutrons are moderated within a large assembly or pile of graphite bricks. The neutron field has previously been well characterised in terms of the fluence rate and energy spectrum at various irradiation positions. However, recent changes to the structure (e.g. enlarging the central irradiation cavity) have prompted a renewal and extension of this work. We have also used Monte Carlo modelling to improve our understanding of the pile's performance.


Assuntos
Laboratórios/normas , Método de Monte Carlo , Nêutrons , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Simulação por Computador , Desenho de Equipamento , Aceleradores de Partículas , Doses de Radiação
14.
Radiat Prot Dosimetry ; 180(1-4): 62-65, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036524

RESUMO

A HPGe detector has been used to measure the photon spectra from the majority of radionuclide neutron sources in use at NPL (252Cf, 241Am-Be, 241Am-Li, 241Am-B). The HPGe was characterised then modelled to produce a response matrix. The measured pulse height spectra were then unfolded to produce photon fluence spectra. Changes in the photon spectrum with time from a 252Cf source are evident. Spectra from a 2-year-old and 42-year-old 252Cf source are presented showing the change from a continuum to peaks from long-lived isotopes of Cf. Other radionuclide neutron source spectra are also presented and discussed. The new spectra were used to improve the photon to neutron dose equivalent ratios from some earlier work at NPL with GM tubes and EPDs.


Assuntos
Amerício/normas , Berílio/normas , Califórnio/normas , Laboratórios/normas , Nêutrons , Fótons , Monitoramento de Radiação/normas , Amerício/análise , Berílio/análise , Calibragem , Califórnio/análise , Simulação por Computador , Método de Monte Carlo , Doses de Radiação
15.
Patient Educ Couns ; 99(10): 1739-46, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27217050

RESUMO

OBJECTIVE: Patient activation can be measured using the Patient Activation Measure (PAM) developed by Hibbard et al., however, little is known about the uses of the PAM in research and in practice. This study aims to explore its differing utility in four UK exemplar sites. METHODS: Data from four exemplars in a range of health settings with people living with long-term conditions (i.e. stroke or COPD) were evaluated. PAM scores were described and explored in relation to clinical and sociodemographic variables and outcome measures. RESULTS: PAM scores illustrated that most with COPD or stroke reported PAM levels of 3 or 4, indicating that they are engaging, but may need help to sustain their scores. The exemplars illustrate the utility of, and potential issues involved in, using PAM as a process/outcome measure to predict activation and the effectiveness of interventions, and as a tool to inform tailoring of targeted interventions. CONCLUSIONS: The PAM tool has been shown to be useful as an outcome measure, a screening tool to tailor education, or a quality indicator for delivery of care. PRACTICE IMPLICATIONS: However good demographic and patient history are needed to substantiate PAM scores. Further work is needed to monitor PAM prospectively.


Assuntos
Avaliação de Resultados da Assistência ao Paciente , Participação do Paciente/métodos , Psicometria/instrumentação , Doença Pulmonar Obstrutiva Crônica/terapia , Autocuidado/psicologia , Inquéritos e Questionários/estatística & dados numéricos , Doença Crônica , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Participação do Paciente/psicologia , Assistência Centrada no Paciente , Estudos Prospectivos , Qualidade de Vida , Reprodutibilidade dos Testes , Estudos Retrospectivos , Inquéritos e Questionários/normas , Reino Unido
16.
Respir Med ; 111: 60-3, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26733228

RESUMO

BACKGROUND: Females with exacerbations of Chronic Obstructive Pulmonary Disease now account for one half of all hospital admissions for that condition and rates have been increasing over the last few decades. Differences in presentations of disease between genders have been shown in several conditions and this study explores whether there are inter gender biases in probable diagnoses in those suspected to have COPD. METHODS: 445 individuals with a provisional diagnosis by their General Practitioner of "suspected COPD" or "definite COPD" were referred to a community Respiratory Assessment unit (CRAU) for tests including spirometry. Gender, demographics, respiratory symptoms and respiratory medical history were recorded. The provisional diagnoses were compared with the final diagnosis made after spirometry and respiratory specialist nurse review and the provisional diagnosis was either confirmed as correct or refuted as unlikely. RESULTS: Significantly more men (87.5%) had their diagnosis of "definite COPD" confirmed compared to 73.9% of women (p = 0.021). When the GP suggested a provisional diagnosis of "suspected COPD" (n = 265) at referral, this was confirmed in 60.9% of men and only 43.2% of women (p = 0.004). There was a different symptom pattern between genders with women being more likely to report allergies, symptoms starting earlier in life, and being less likely than men to report breathlessness as the main symptom. CONCLUSIONS: These results may suggest a difference between genders in some of the clinical features of COPD and a difference in likelihood of a GPs provisional diagnosis of COPD being correct. The study reiterates the absolute importance of spirometry in the diagnosis of COPD.


Assuntos
Atenção Primária à Saúde/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Espirometria/métodos , Idoso , Inglaterra/epidemiologia , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde/estatística & dados numéricos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fatores Sexuais , Espirometria/estatística & dados numéricos , País de Gales/epidemiologia
17.
Radiat Prot Dosimetry ; 161(1-4): 216-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24319105

RESUMO

The AECL Bonner Sphere Spectrometer (BSS) was taken to National Physical Laboratory (NPL) for calibration in mono-energetic neutron fields and bare (252)Cf neutron fields. The mono-energetic radiations were performed using ISO-8529 prescribed neutron energies: 0.071, 0.144, 0.565, 1.2, 5 and 17 MeV. A central SP9 proportional counter was also evaluated at the NPL thermal neutron calibration facility in order to assess an effective pressure of (3)He inside the counter, i.e. number density of (3)He atoms. Based on these measurements and methods outlined by Thomas and Soochak, a new BSS response matrix was generated. The response matrix is then verified by unfolding spectra corresponding to various neutron fields. Those are NPL bare (252)Cf source, National Institute of Standards and Technology bare and heavy water moderated (252)Cf source and (241)AmBe calibration source located at National Research Council. A good agreement was observed with expected neutron fluence rates, as well as derived dosimetric quantities, such as International Commission on Radiological Protection-74 ambient dose equivalent.


Assuntos
Nêutrons , Radiometria/instrumentação , Radiometria/métodos , Algoritmos , Amerício , Berílio , Calibragem , Califórnio , Canadá , Desenho de Equipamento , Hélio , Método de Monte Carlo , Polietileno/química , Linguagens de Programação , Reprodutibilidade dos Testes , Software
18.
Radiat Prot Dosimetry ; 161(1-4): 253-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24191120

RESUMO

Hydrogen-filled proportional counters perform well as neutron spectrometers in the energy region from a few tens of keV up to ∼1.5 MeV. Unfortunately, gamma rays also generate signals in these detectors. It is possible in principle to distinguish the two types of event via the rise time of their respective signal pulses, but the data acquisition system needed for this is complex to assemble and adjust if one uses conventional modular analogue electronics. In this work a digital sampling system, in conjunction with custom software, was used to measure and acquire amplitude and rise time data from type SP2 counters. The interpretation of the data was supported by a Monte Carlo calculation. The performance of the system is compared with that of a conventional 1-parameter analogue system, and the potential of the digital technique to supplant conventional methods is discussed.


Assuntos
Hidrogênio/química , Proteção Radiológica/métodos , Radiometria/instrumentação , Radiometria/métodos , Eletrodos , Eletrônica , Desenho de Equipamento , Raios gama , Vidro , Método de Monte Carlo , Nêutrons , Reprodutibilidade dos Testes , Software
19.
Radiat Prot Dosimetry ; 161(1-4): 157-60, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24126485

RESUMO

Standard neutron fields are invariably accompanied by a photon component due to the neutron-generating reactions and secondary neutron interactions in the surrounding environment. A set of energy-compensated Geiger-Müller (GM) tubes and electronic personal dosemeters (EPDs) have been used to measure the photon dose rates in a number of standard radionuclide and accelerator-based neutron fields. The GM tubes were first characterised in standard radioisotope and X-ray photon fields and then modelled using MCNP to determine their photon dose response as a function of energy. Values for the photon-to-neutron dose equivalent ratios are presented and compared with other published values.


Assuntos
Nêutrons , Fótons , Doses de Radiação , Radiometria/instrumentação , Calibragem , Califórnio , Eletrodos , Modelos Teóricos , Método de Monte Carlo , Aceleradores de Partículas , Radioisótopos/química , Radiometria/métodos , Reprodutibilidade dos Testes , Raios X
20.
Radiat Prot Dosimetry ; 161(1-4): 225-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24126487

RESUMO

High-resolution neutron energy spectra, covering the entire energy range of interest, for two standard radionuclide neutron sources ((241)Am-B and (241)Am-F) have been derived from Bonner sphere measurements by using high-resolution a priori data in the unfolding process. In each case, two a priori spectra were used, one from a two-stage calculation and also one from a combination of the calculated spectrum with a high-resolution measured spectrum. The unfolded spectra are compared with those published elsewhere and show significant differences from the ISO- and IAEA-recommended spectra for (241)Am-B and (241)Am-F, respectively. Values for the fluence-average energy and fluence-to-dose-equivalent conversion coefficients are presented for the new spectra, and the implications of the new spectra for the emission rates of the sources when measured by the manganese bath technique are also determined.


Assuntos
Amerício/química , Boro/química , Fluoretos/química , Nêutrons , Monitoramento de Radiação/instrumentação , Algoritmos , Simulação por Computador , Desenho de Equipamento , Hélio , Íons , Manganês/química , Método de Monte Carlo , Polietileno/química , Doses de Radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Radioisótopos/análise , Espectrofotometria
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