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1.
Sci Rep ; 13(1): 17573, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845245

RESUMO

The structures, strain fields, and defect distributions in solid materials underlie the mechanical and physical properties across numerous applications. Many modern microstructural microscopy tools characterize crystal grains, domains and defects required to map lattice distortions or deformation, but are limited to studies of the (near) surface. Generally speaking, such tools cannot probe the structural dynamics in a way that is representative of bulk behavior. Synchrotron X-ray diffraction based imaging has long mapped the deeply embedded structural elements, and with enhanced resolution, dark field X-ray microscopy (DFXM) can now map those features with the requisite nm-resolution. However, these techniques still suffer from the required integration times due to limitations from the source and optics. This work extends DFXM to X-ray free electron lasers, showing how the [Formula: see text] photons per pulse available at these sources offer structural characterization down to 100 fs resolution (orders of magnitude faster than current synchrotron images). We introduce the XFEL DFXM setup with simultaneous bright field microscopy to probe density changes within the same volume. This work presents a comprehensive guide to the multi-modal ultrafast high-resolution X-ray microscope that we constructed and tested at two XFELs, and shows initial data demonstrating two timing strategies to study associated reversible or irreversible lattice dynamics.

2.
BJGP Open ; 5(5)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34465579

RESUMO

BACKGROUND: Epidemiological evidence for specific long-term conditions is required to inform best practices regarding the substantial health inequalities experienced by sexual minority individuals compared with heterosexual peers. AIM: To describe inequalities in long-term conditions among sexual minority (lesbian, gay, and bisexual [LGB]) adults. DESIGN & SETTING: Cross-sectional analysis of 1 341 339 nationally representative survey responses from the English GP Patient Survey (GPPS). METHOD: Stratifying by sex, the weighted prevalence and covariate-adjusted association of 15 long-term conditions were calculated, comparing sexual minority and heterosexual adults, considering variation by sexual orientation and variation in sexual orientation inequalities by deprivation, ethnic group, region, and age. RESULTS: After adjusting for deprivation, ethnic group, region, and age, 13 long-term conditions (all except cancer and hypertension) were more prevalent among sexual minority women than their heterosexual peers, with the largest inequalities for mental health problems (odds ratio [OR] 2.8, 95% confidence interval [CI] = 2.7 to 3.0), neurological conditions (OR 1.7, 95% CI = 1.5 to 1.8), dementia (OR 1.6, 95% CI = 1.3 to 1.9), and back problems (OR 1.4, 95% CI = 1.3 to 1.5). It was found that nine long-term conditions were also more prevalent among sexual minority men including mental health problems (OR 2.3, 95% CI = 2.2 to 2.4), 'all other conditions' (OR 1.8, 95% CI = 1.7 to 1.8), neurological conditions (OR 1.5, 95% CI = 1.4 to 1.6), and kidney or liver disease (OR 1.4, 95% CI = 1.3 to 1.5); inequalities were often largest for bisexual adults. Inequalities did not vary significantly by deprivation, ethnic group, or region except for mental health problems. Inequalities in multimorbidity were highest at younger ages; for example, LGB women aged 18-24 years had multimorbidity at the same level (approximately 20%) as heterosexual women aged 45-54 years. CONCLUSION: Sexual minority adults, especially bisexual adults, are at elevated risk for many long-term conditions and multimorbidity; this risk spans socioeconomic status and ethnic group, representing a significant healthcare challenge.

3.
Rev Sci Instrum ; 92(5): 053901, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243295

RESUMO

We describe two orthogonal radiography geometries at the OMEGA EP laser facility, which we refer to as side-on and face-on radiography. This setup can be used to determine quantitative information about the areal densities in solid, particulate, or liquid samples. We show sample images from these two different platforms that use the radiography diagnostic, one of material microjetting by the Richtmeyer-Meshkov instability and one of a deforming tin sample by the Rayleigh-Taylor instability, demonstrating the versatile applicability of such measurements in the field of high-energy density physics. The analytical methodology behind the quantitative Rayleigh-Taylor face-on radiography is also demonstrated and can be applied to other types of samples.

4.
Chaos ; 22(1): 013127, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22463003

RESUMO

We address the issue of multi-parameter estimation from scalar outputs of chaotic systems, using the dynamics of a Malkus water wheel and simulations of the corresponding Lorenz-equations model as an example. We discuss and compare two estimators: one is based on a globally convergent adaptive observer and the second is an extended Kalman filter (EKF). Both estimators can identify all three unknown parameters of the model. We find that the estimated parameter values are in agreement with those obtained from direct measurements on the experimental system. In addition, we explore the question of how to distinguish the impact of noise from those of model imperfections by investigating a model generalization and the use of uncertainty estimates provided by the extended Kalman filter. Although we are able to exclude asymmetric inflow as a possible unmodeled effect, our results indicate that the Lorenz-equations do not perfectly describe the water wheel dynamics.


Assuntos
Algoritmos , Transferência de Energia , Dinâmica não Linear , Oscilometria/métodos , Simulação por Computador , Movimento (Física) , Água
5.
Clin Child Psychol Psychiatry ; 15(4): 511-27, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20923900

RESUMO

Children in out-of-home care (OOHC) present with high levels of physical, developmental and emotional and behavioural difficulties, yet often fail to receive appropriate services. This article describes a joint health and welfare service specifically developed to provide comprehensive physical, developmental and mental health assessments to a cohort of children entering long-term care in one region of Sydney, New South Wales (NSW), Australia. Paediatric, allied health, dental and psychosocial assessments were co-ordinated from a single referral from the child's welfare case manager. Follow-up appointments were held 6-12 months later to assess the outcomes of recommendations. Physical, mental health and developmental difficulties in the children are reported, the implications for service requirements are presented and process blocks described. There is a need for a specific co-ordinating service to overcome the inherent fragmentation of this group (related both to transience and change in the welfare sector, and levels of comorbidity and chronicity in health presentations). Health and Welfare services must operate together, with an awareness of the processes and resource constraints in each sector, if they are to deliver sustainable and reliable health care to this vulnerable group.


Assuntos
Maus-Tratos Infantis/reabilitação , Assistência Integral à Saúde/organização & administração , Continuidade da Assistência ao Paciente/organização & administração , Cuidados no Lar de Adoção , Relações Interinstitucionais , Criança , Maus-Tratos Infantis/psicologia , Pré-Escolar , Deficiências do Desenvolvimento/prevenção & controle , Feminino , Humanos , Lactente , Masculino , Programas de Rastreamento/organização & administração , Transtornos Mentais/prevenção & controle , New South Wales , Desenvolvimento de Programas , Encaminhamento e Consulta/organização & administração
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