1,269 research outputs found
Increasing Light Absorption and Collection Using Engineered Structures
In recent years we have witnessed an explosion of interest in two dimensional (2D) materials, due to their unique physical properties. Excitement surrounds the promise of replacing conventional bulk photodetectors with devices based on 2D materials, allowing better integration, flexibility and potentially improving performance. However, the low inherent light absorption of 2D materials is an outstanding issue to be solved. In this chapter we review two independent approaches to tackling this problem, which have the potential to be combined to find a robust solution. The first approach involves patterning the substrate with a rod-type photonic crystal (PhC) cavity structure, which is shown to increase the light absorption into a 2D material flake coupled spatially to the cavity mode. Secondly, we review 2D–compatible solid immersion lenses (SILs) and their ability to increase both the optical magnification of the structures they encapsulate, and the longevity of the material. SILs have been shown to reduce the requirements for complex optics in the implementation of 2D materials in optoelectronic devices, and also in preserving the photodetector’s optical performance over long periods of time. Finally, we show how by combining rod-type PhC cavities with SILs, we can improve the performance of 2D material-based photodetectors
328 Exploring parents' concerns about transition from paediatric to adult cystic fibrosis (CF) services
Review of Injection Therapy Clinics Performed by Physiotherapists Working in Primary Care.
Objectives
To determine painscores for injection therapy and to review the overall change in outcomes post injection for a variety of musculoskeletal injections compared with the previous audits of a NHS Primary care Physiotherapy injection clinic.
Methods
Subjects were assessed using a numerical rating scale between 0 to 10 before and 4 weeks post injection.
Results
All average painscale scores were reduced 4 weeks after injection for all conditions. There is an overall average reduction in pain on provoking activity of 45.7%. Trigger finger/thumb (65.0%) demonstrated the most significant reduction in pain.
Contrary to a common patient perception, injection therapy is not an exceptionally painful experience, with an average score of 3.2.
Discussion
Results are comparable with previous scores for injections carried out within the same NHS Primary care Physiotherapy clinic
Optical identification using imperfections in 2D materials
The ability to uniquely identify an object or device is important for authentication [1]. Imperfections, locked into structures during fabrication, can be used to provide a fingerprint that is challenging to reproduce. In this paper, we propose a simple optical technique to read unique information from nanometer-scale defects in 2D materials. Imperfections created during crystal growth or fabrication lead to spatial variations in the bandgap of 2D materials that can be characterized through photoluminescence measurements. We show a simple setup involving an angle- adjustable transmission filter, simple optics and a CCD camera can capture spatially- dependent photoluminescence to produce complex maps of unique information from 2D monolayers. Atomic force microscopy is used to verify the origin of the optical signature measured, demonstrating that it results from nanometer-scale imperfections. This solution to optical identification with 2D materials could be employed as a robust security measure to prevent counterfeiting
Intelligence within BAOR and NATO's Northern Army Group
During the Cold War the UK's principal military role was its commitment to the North Atlantic Treaty Organisation (NATO) through the British Army of the Rhine (BAOR), together with wartime command of NATO's Northern Army Group. The possibility of a surprise attack by the numerically superior Warsaw Pact forces ensured that great importance was attached to intelligence, warning and rapid mobilisation. As yet we know very little about the intelligence dimension of BAOR and its interface with NATO allies. This article attempts to address these neglected issues, ending with the impact of the 1973 Yom Kippur War upon NATO thinking about warning and surprise in the mid-1970s. It concludes that the arrangements made by Whitehall for support to BAOR from national assets during crisis or transition to war were - at best - improbable. Accordingly, over the years, BAOR developed its own unique assets in the realm of both intelligence collection and special operations in order to prepare for the possible outbreak of conflict
Photoluminescence studies of individual and few GaSb/GaAs quantum rings
We present optical studies of individual and few GaSb quantum rings embedded in a GaAs matrix. Contrary to expectation for type-II confinement, we measure rich spectra containing sharp lines. These lines originate from excitonic recombination and are observed to have resolution-limited full-width at half maximum of 200 µeV. The detail provided by these measurements allows the characteristic type-II blueshift, observed with increasing excitation power, to be studied at the level of individual nanostructures. These findings are in agreement with hole-charging being the origin of the observed blueshif
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A comparison of single and intersectional social identities associated with discrimination and mental health service use: data from the 2014 Adult Psychiatric Morbidity Survey in England
Inequities in mental health service use (MHSU) and treatment are influenced by social stratification processes linked to socially contextualised interactions between individuals, organisations and institutions. These complex relations underpin observed inequities and their experience by people at the intersections of social statuses. Discrimination is one important mechanism influencing such differences. We compared inequities in MHSU/treatment through single and intersectional status analyses, accounting for need. We assessed whether past-year discrimination differentially influences MHSU/treatment across single and intersecting statuses. Data came from a population survey (collected 2014–2015) nationally representative of English households (N = 7546). We used a theory and datadriven approach (latent class analysis) which identified five intersectional groups in the population comprising common combinations of social statuses. Single status analyses identified characteristics associated with MHSU/treatment (being a sexual minority (adjusted odds ratio (AOR) 1.65 95% CI:1.09-2.50), female (AOR 1.71, 95% CI:1.45–2.02), economically inactive (AOR 2.02, 95% CI:1.05–3.90), in the most deprived quintile (AOR 1.33, 95% CI:1.02–1.74), and Black (AOR 0.36 95% CI:0.20–0.66)). Intersectional analyses detected patterns not apparent from single status analyses. Compared to the most privileged group (“White British, highly educated, employed, high social class”), “Retired WhiteBritish” had greater odds of MHSU/treatment (AOR 1.88, 95% CI:1.53-2.32) while “Employed migrants” had lower odds (AOR 0.39, 95% CI:0.27–0.55). Past-year discrimination was associated with certain disadvantaged social statuses and greater MHSU/treatment but—except for sexual minorities—adjusting for discrimination had little influence using either analytic approach. Observing patterns only by single social statuses masks potentially unanticipated and contextually varying inequities. The latent class approach offers policy-relevant insights into patterns and mechanisms of inequity but may mask other key intersectional patterns by statuses less common or under represented in surveys (e.g. UK-born ethnic minority groups). We propose multiple, context-relevant, theory-driven approaches to intersectional understanding of mental health inequalities
Fanny Copeland and the geographical imagination
Raised in Scotland, married and divorced in the English south, an adopted Slovene, Fanny Copeland (1872 – 1970) occupied the intersection of a number of complex spatial and temporal conjunctures. A Slavophile, she played a part in the formation of what subsequently became the Kingdom of Yugoslavia that emerged from the First World War. Living in Ljubljana, she facilitated the first ‘foreign visit’ (in 1932) of the newly formed Le Play Society (a precursor of the Institute of British Geographers) and guided its studies of Solčava (a then ‘remote’ Alpine valley system) which, led by Dudley Stamp and commended by Halford Mackinder, were subsequently hailed as a model for regional studies elsewhere. Arrested by the Gestapo and interned in Italy during the Second World War, she eventually returned to a socialist Yugoslavia, a celebrated figure. An accomplished musician, linguist, and mountaineer, she became an authority on (and populist for) the Julian Alps and was instrumental in the establishment of the Triglav National Park. Copeland’s role as participant observer (and protagonist) enriches our understanding of the particularities of her time and place and illuminates some inter-war relationships within G/geography, inside and outside the academy, suggesting their relative autonomy in the production of geographical knowledge
Incidence of community-acquired lower respiratory tract infections and pneumonia among older adults in the United Kingdom: a population-based study.
Community-acquired lower respiratory tract infections (LRTI) and pneumonia (CAP) are common causes of morbidity and mortality among those aged ≥65 years; a growing population in many countries. Detailed incidence estimates for these infections among older adults in the United Kingdom (UK) are lacking. We used electronic general practice records from the Clinical Practice Research Data link, linked to Hospital Episode Statistics inpatient data, to estimate incidence of community-acquired LRTI and CAP among UK older adults between April 1997-March 2011, by age, sex, region and deprivation quintile. Levels of antibiotic prescribing were also assessed. LRTI incidence increased with fluctuations over time, was higher in men than women aged ≥70 and increased with age from 92.21 episodes/1000 person-years (65-69 years) to 187.91/1000 (85-89 years). CAP incidence increased more markedly with age, from 2.81 to 21.81 episodes/1000 person-years respectively, and was higher among men. For both infection groups, increases over time were attenuated after age-standardisation, indicating that these rises were largely due to population aging. Rates among those in the most deprived quintile were around 70% higher than the least deprived and were generally higher in the North of England. GP antibiotic prescribing rates were high for LRTI but lower for CAP (mostly due to immediate hospitalisation). This is the first study to provide long-term detailed incidence estimates of community-acquired LRTI and CAP in UK older individuals, taking person-time at risk into account. The summary incidence commonly presented for the ≥65 age group considerably underestimates LRTI/CAP rates, particularly among older individuals within this group. Our methodology and findings are likely to be highly relevant to health planners and researchers in other countries with aging populations
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