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1.
BMC Public Health ; 21(1): 695, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33836714

RESUMO

BACKGROUND: Variable selection is an important issue in many fields such as public health and psychology. Researchers often gather data on many variables of interest and then are faced with two challenging goals: building an accurate model with few predictors, and making probabilistic statements (inference) about this model. Unfortunately, it is currently difficult to attain these goals with the two most popular methods for variable selection methods: stepwise selection and LASSO. The aim of the present study was to demonstrate the use predictive projection feature selection - a novel Bayesian variable selection method that delivers both predictive power and inference. We apply predictive projection to a sample of New Zealand young adults, use it to build a compact model for predicting well-being, and compare it to other variable selection methods. METHODS: The sample consisted of 791 young adults (ages 18 to 25, 71.7% female) living in Dunedin, New Zealand who had taken part in the Daily Life Study in 2013-2014. Participants completed a 13-day online daily diary assessment of their well-being and a range of lifestyle variables (e.g., sleep, physical activity, diet variables). The participants' diary data was averaged across days and analyzed cross-sectionally to identify predictors of average flourishing. Predictive projection was used to select as few predictors as necessary to approximate the predictive accuracy of a reference model with all 28 predictors. Predictive projection was also compared to other variable selection methods, including stepwise selection and LASSO. RESULTS: Three predictors were sufficient to approximate the predictions of the reference model: higher sleep quality, less trouble concentrating, and more servings of fruit. The performance of the projected submodel generalized well. Compared to other variable selection methods, predictive projection produced models with either matching or slightly worse performance; however, this performance was achieved with much fewer predictors. CONCLUSION: Predictive projection was used to efficiently arrive at a compact model with good predictive accuracy. The predictors selected into the submodel - felt refreshed after waking up, had less trouble concentrating, and ate more servings of fruit - were all theoretically meaningful. Our findings showcase the utility of predictive projection in a practical variable selection problem.


Assuntos
Dieta , Frutas , Adolescente , Adulto , Teorema de Bayes , Feminino , Humanos , Estilo de Vida , Masculino , Nova Zelândia/epidemiologia , Adulto Jovem
2.
BMC Pediatr ; 19(1): 150, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31088415

RESUMO

BACKGROUND: Childhood unintentional injuries (UI) are common but continue to happen more often to children living in less advantaged socioeconomic circumstances (SEC). Our aim was to explore how early life factors mediate the association between SEC and UIs, using the UK Millennium Cohort Study. METHODS: We calculated risk ratios (RR) and 95% confidence intervals (95%CI) for parental report of UI occurring between age 3 and 5 years, using Poisson regression according to family income as a measure of SEC. We explored potentially mediating pathways by controlling associations between SEC and UI for groups of early life risks in three domains: factors that may influence environmental safety, supervision and the MCS child's abilities and behaviours. RESULTS: Twenty eight percent of children had a UI from 3 to 5 years old. Children from the lowest income quintile were more likely to be injured compared to those from the highest (RR 1.20 95%CI 1.05, 1.37). Sequentially controlling for early life factors that may influence environmental safety (RR 1.19 95%CI 1.02, 1.38), then supervision (RR 1.18, 95%CI 1.02, 1.36), and finally adding child's behaviour and abilities (RR 1.15, 95%CI 1.00, 1.34) into the model reduced the RR by 5, 10 and 25% respectively. CONCLUSIONS: Addressing factors that may influence environmental safety and supervision, and the child's abilities and behaviours only partly explains the increased UI risk between the highest and lowest income quintiles. Further research is required to explore factors mediating associations between SEC and specific mechanisms and types of injuries.


Assuntos
Lesões Acidentais/diagnóstico , Lesões Acidentais/epidemiologia , Proteção da Criança , Renda , Fatores Etários , Distribuição de Qui-Quadrado , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Escala de Gravidade do Ferimento , Estudos Longitudinais , Masculino , Razão de Chances , Prevalência , Medição de Risco , Fatores Socioeconômicos , Reino Unido/epidemiologia
3.
Psychol Med ; 45(7): 1495-507, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25388512

RESUMO

BACKGROUND: A growing body of research has investigated associations between insecure attachment styles and psychosis. However, despite good theoretical and epidemiological reasons for hypothesising that insecure attachment may be specifically implicated in paranoid delusions, few studies have considered the role it plays in specific symptoms. METHOD: We examined the relationship between attachment style, paranoid beliefs and hallucinatory experiences in a sample of 176 people with a diagnosis of schizophrenia spectrum disorders and 113 healthy controls. We also investigated the possible role of negative self-esteem in mediating this association. RESULTS: Insecure attachment predicted paranoia but not hallucinations after co-morbidity between the symptoms was controlled for. Negative self-esteem partially mediated the association between attachment anxiety and clinical paranoia, and fully mediated the relationship between attachment avoidance and clinical paranoia. CONCLUSIONS: It may be fruitful to explore attachment representations in psychological treatments for paranoid patients. If future research confirms the importance of disrupted attachment as a risk factor for persecutory delusions, consideration might be given to how to protect vulnerable young people, for example those raised in children's homes.


Assuntos
Alucinações/fisiopatologia , Apego ao Objeto , Transtornos Paranoides/fisiopatologia , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Autoimagem , Adulto , Feminino , Alucinações/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Paranoides/etiologia , Transtornos Psicóticos/complicações , Esquizofrenia/complicações
4.
J Struct Biol ; 174(2): 290-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21272646

RESUMO

The structure of the porous three-dimensional reticulated pattern in the wing scales of the butterfly Callophrys rubi (the Green Hairstreak) is explored in detail, via scanning and transmission electron microscopy. A full 3D tomographic reconstruction of a section of this material reveals that the predominantly chitin material is assembled in the wing scale to form a structure whose geometry bears a remarkable correspondence to the srs net, well-known in solid state chemistry and soft materials science. The porous solid is bounded to an excellent approximation by a parallel surface to the Gyroid, a three-periodic minimal surface with cubic crystallographic symmetry I4132, as foreshadowed by Stavenga and Michielson. The scale of the structure is commensurate with the wavelength of visible light, with an edge of the conventional cubic unit cell of the parallel-Gyroid of approximately 310 nm. The genesis of this structure is discussed, and we suggest it affords a remarkable example of templating of a chiral material via soft matter, analogous to the formation of mesoporous silica via surfactant assemblies in solution. In the butterfly, the templating is achieved by the lipid-protein membranes within the smooth endoplasmic reticulum (while it remains in the chrysalis), that likely form cubic membranes, folded according to the form of the Gyroid. The subsequent formation of the chiral hard chitin framework is suggested to be driven by the gradual polymerisation of the chitin precursors, whose inherent chiral assembly in solution (during growth) promotes the formation of a single enantiomer.


Assuntos
Borboletas , Quitina/química , Asas de Animais/química , Animais , Configuração de Carboidratos , Tomografia com Microscopia Eletrônica , Fenômenos Ópticos
5.
BMJ Open ; 10(11): e041774, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33234654

RESUMO

OBJECTIVE: To assess trends in inequalities in Children Looked After (CLA) in England between 2004 and 2019, after controlling for unemployment, a marker of recession and risk factor for child maltreatment. DESIGN: Longitudinal local area ecological analysis. SETTING: 150 English upper-tier local authorities. PARTICIPANTS: Children under the age of 18 years. PRIMARY OUTCOME MEASURE: The annual age-standardised rate of children starting to be looked after (CLA rate) across English local authorities, grouped into quintiles based on their level of income deprivation. Slope indices of inequality were estimated using longitudinal segmented mixed-effects models, controlling for unemployment. RESULTS: Since 2008, there has been a precipitous rise in CLA rates and a marked widening of inequalities. Unemployment was associated with rising CLA rates: for each percentage point increase in unemployment rate, an estimated additional 9 children per 100 000 per year (95% CI 6 to 11) became looked after the following year. However, inequalities increased independently of the effect of unemployment. Between 2007 and 2019, after controlling for unemployment, the gap between the most and least deprived areas increased by 15 children per 100 000 per year (95% CI 4 to 26) relative to the 2004-2006 trend. CONCLUSIONS: The dramatic increase in the rate of children starting to be looked after has been greater in poorer areas and in areas more deeply affected by recession. But trends in unemployment do not explain the decade-long rise in inequalities, suggesting that other socioeconomic factors, including rising child poverty and reduced spending on children's services, may be fuelling inequalities. Policies to safely reduce the CLA rate should urgently address the social determinants of child health and well-being.


Assuntos
Proteção da Criança , Disparidades nos Níveis de Saúde , Desemprego , Adolescente , Criança , Inglaterra , Humanos , Áreas de Pobreza , Fatores Socioeconômicos
7.
Nat Commun ; 7: 13715, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27941751

RESUMO

Mechanosensitive biological nanomachines such as motor proteins and ion channels regulate diverse cellular behaviour. Combined optical trapping with single-molecule fluorescence imaging provides a powerful methodology to clearly characterize the mechanoresponse, structural dynamics and stability of such nanomachines. However, this system requires complicated experimental geometry, preparation and optics, and is limited by low data-acquisition efficiency. Here we develop a programmable DNA origami nanospring that overcomes these issues. We apply our nanospring to human myosin VI, a mechanosensory motor protein, and demonstrate nanometre-precision single-molecule fluorescence imaging of the individual motor domains (heads) under force. We observe force-induced transitions of myosin VI heads from non-adjacent to adjacent binding, which correspond to adapted roles for low-load and high-load transport, respectively. Our technique extends single-molecule studies under force and clarifies the effect of force on biological processes.


Assuntos
Cadeias Pesadas de Miosina/química , Nanotecnologia , Transporte Biológico , Humanos , Mecanotransdução Celular , Cadeias Pesadas de Miosina/ultraestrutura , Imagem Óptica
8.
J Epidemiol Community Health ; 70(5): 452-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26646692

RESUMO

BACKGROUND: Many governments have introduced tougher eligibility assessments for out-of-work disability benefits, to reduce rising benefit caseloads. The UK government initiated a programme in 2010 to reassess all existing disability benefit claimants using a new functional checklist. We investigated whether this policy led to more people out-of-work with long-standing health problems entering employment. METHOD: We use longitudinal data from the Labour Force Survey linked to data indicating the proportion of the population experiencing a reassessment in each of 149 upper tier local authorities in England between 2010 and 2013. Regression models were used to investigate whether the proportion of the population undergoing reassessment in each area was independently associated with the chances that people out-of-work with a long-standing health problem entered employment and transitions between inactivity and unemployment. We analysed whether any effects differed between people whose main health problem was mental rather than physical. RESULTS: There was no significant association between the reassessment process and the chances that people out-of-work with a long-standing illness entered employment. The process was significantly associated with an increase in the chances that people with mental illnesses moved from inactivity into unemployment (HR=1.22, 95% CI 1.03 to 1.45). CONCLUSIONS: The reassessment policy appears to have shifted people with mental health problems from inactivity into unemployment, but there was no evidence that it had increased their chances of employment. There is an urgent need for services that can support the increasing number of people with mental health problems on unemployment benefits.


Assuntos
Pessoas com Deficiência , Emprego , Revisão da Utilização de Seguros , Seguro por Deficiência , Avaliação da Capacidade de Trabalho , Inglaterra , Feminino , Humanos , Masculino , Inquéritos e Questionários
9.
Animal ; 9(5): 878-87, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25583376

RESUMO

Qualitative behavioural assessment (QBA) is based on observers' ability to capture the dynamic complexity of an animal's demeanour as it interacts with the environment, in terms such as tense, anxious or relaxed. Sensitivity to context is part of QBA's integrative capacity and discriminatory power; however, when not properly managed it can also be a source of undesirable variability and bias. This study investigated the sensitivity of QBA to variations in the visual or verbal information provided to observers, using free-choice profiling (FCP) methodology. FCP allows observers to generate their own descriptive terms for animal demeanour, against which each animal's expressions are quantified on a visual analogue scale. The resulting scores were analysed with Generalised Procrustes Analysis (GPA), generating two or more multi-variate dimensions of animal expression. Study 1 examined how 63 observers rated the same video clips of individual sheep during land transport, when these clips were interspersed with two different sets of video footage. Scores attributed to the sheep in the two viewing sessions correlated significantly (GPA dimension 1: r s =0.95, P<0.001, GPA dimension 2: r s =0.66, P=0.037) indicating that comparative rankings of animals on expressive dimensions were highly similar, however, their mean numerical scores on these dimensions had shifted (RM-ANOVA: Dim1: P<0.001, Dim2: P<0.001). Study 2 investigated the effect of being given different amounts of background information on two separate groups of observers assessing footage of 22 individual sheep in a behavioural demand facility. One group was given no contextual information regarding this facility, whereas the second group was told that animals were moving towards and away from a feeder (in view) to access feed. Scores attributed to individual sheep by the two observer groups correlated significantly (Dim1: r s =0.92, P<0.001, Dim2: r s =0.52, P=0.013). A number of descriptive terms were generated by both observer groups and used in similar ways, other terms were unique to each group. The group given additional information about the experimental facility scored the sheep's behaviour as more 'directed' and 'focused' than observers who had not been told. Thus, in neither of the two studies did experimentally imposed variations in context alter the characterisations of animals relative to each other, but in Study 1 this did affect the mean numerical values underlying these characterisations, indicating a need for careful attention to the use of visual analogue scales.


Assuntos
Bem-Estar do Animal/normas , Carneiro Doméstico/fisiologia , Percepção Visual , Animais , Feminino , Variações Dependentes do Observador , Reprodutibilidade dos Testes
10.
Autoimmunity ; 37(5): 393-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15621563

RESUMO

Herpes stromal keratitis (HSK) is a significant inflammatory disease of the cornea as a result of herpes simplex virus (HSV) infection often progressing to vision loss if left untreated. However, even with immunosuppressive compounds and anti-viral drug treatment, HSV continues to be the leading cause of infectious corneal blindness in the industrialized world. The inflammatory nature of the disease is the root of the pathogenic process characterized by irreversible corneal scarring, neovascularization of the avascular cornea, and infiltration of activated leukocytes. Experimental evidence using mice suggest HSK is the result of either molecular mimicry or a bystander activation phenomenon. This review will revisit the basis of HSK focusing on issues that pertain to the autoimmune component versus collateral damage as a result of non-specific activation as a means to explain the pathologic manifestations of the disease.


Assuntos
Efeito Espectador/imunologia , Imunidade Inata/imunologia , Ceratite Herpética/imunologia , Mimetismo Molecular/imunologia , Animais , Camundongos
11.
Eur J Protistol ; 25(4): 345-52, 1990 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23196048

RESUMO

Optimal conditions for growth of 9 strains from 7 species of colpodean ciliates were determined using a factorial experimental design. Estimates of maximal growth rate were higher than those previously obtained for similar-sized ciliates. Using published cell size estimates, the slope of a cell size-growth rate relation was found to be not significantly different from zero, either when maximal growth rates were used or when all growth rates were scaled to 20°C, a suboptimal temperature. Both macronuclear DNA content and the ratio of macro- to micronuclear DNA were good predictors of maximal growth rate, but the ratio was not more predictive than macronuclear DNA content alone. The slope of the relation between minimum generation time and macronuclear DNA content was significantly less than that predicted by the skeletal-DNA theory of Cavalier-Smith. There was no significant relationship between gene concentration (measured as the ratio of macronuclear to micronuclear DNA, divided by cell volume) and maximal growth rate.

12.
Patient Educ Couns ; 38(3): 217-25, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10865687

RESUMO

The study assessed the information needs of women receiving a course of radiation therapy (RT) for breast cancer and the relationship between information needs and preference for information. Thirty-three women were interviewed during the first (T1), third (T2), and last week of RT (T3), and one month later (T4) using the Toronto Informational Needs Questionnaire--Breast Cancer and the Information Subscale of the Health Opinion Survey. Information need scores were high and did not differ significantly across time. Information need and preference for information were correlated only at T1. Findings indicate that women with breast cancer receiving RT have high information needs and preference for information may not be a meaningful indicator of their desire for information. Health care providers need to assess the women's information needs frequently and be prepared to offer on-going educational support.


Assuntos
Neoplasias da Mama/psicologia , Neoplasias da Mama/radioterapia , Avaliação das Necessidades/organização & administração , Educação de Pacientes como Assunto/métodos , Satisfação do Paciente , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários , Fatores de Tempo
13.
Oncol Nurs Forum ; 20(6): 953-7, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8367347

RESUMO

In nursing, a gap sometimes exists between research and practice. This paper discusses how a group of 11 nurses successfully bridged this gap. The group was composed of nurses from a large teaching hospital, a regional outpatient cancer center, and a university. The result of the group's work over a two-year period was an externally funded research proposal. This paper discusses the strategies that led to the group's success and provides specific recommendations for nurses who want to form similar groups.


Assuntos
Relações Interprofissionais , Prática do Docente de Enfermagem/organização & administração , Pesquisa em Enfermagem/organização & administração , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Enfermagem Oncológica/organização & administração , Institutos de Câncer , Hospitais Universitários , Descrição de Cargo , Objetivos Organizacionais , Escolas de Enfermagem
14.
J Anim Sci ; 90(12): 4523-35, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22829616

RESUMO

Objective and issue-neutral qualitative assessments of livestock behavior could provide a powerful assessment of welfare, augmenting quantitative measures such as autonomic and endocrine changes, which are often difficult to assess under many commercial livestock conditions. We set out to validate the use of qualitative behavioral assessment (QBA) in sheep using controlled experimental conditions (transport as a challenge) and comparing assessments against physiological variables. The behavioral expression of 14 Merino wethers, which had never experienced land transport, were assessed during their first road event (naïve to transport), and then again on their seventh event, 8 d later (habituated to transport). Blood samples were collected immediately before loading and after unloading, and heart rate and core body temperature were measured continuously throughout each event. Continuous video footage recorded during each event was used to provide clips of individual animals that were shown to observers for QBA. There was significant consensus (P < 0.001) amongst 63 observers in terms of their assessment of the behavioral expression of the sheep. Transport-naïve sheep were assessed as being more 'alert', 'anxious', and 'aware', whereas transport-habituated sheep were more 'comfortable', 'tired', and 'confident' (P = 0.015). Heart rate and heart rate variability, core body temperature and a stress leukogram were greater (P < 0.05) in sheep during the first (naïve) event compared with the habituated event, and were significantly correlated with the QBA scores (P < 0.05). In conclusion, QBA is a valid, practical and informative measure of behavioral responses to transport.


Assuntos
Comportamento Animal , Ovinos/fisiologia , Estresse Fisiológico , Meios de Transporte , Animais , Biomarcadores/sangue , Temperatura Corporal , Feminino , Frequência Cardíaca , Humanos , Masculino , Variações Dependentes do Observador , Ovinos/sangue
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