Semiconductor cooling by thin-film thermocouples

Thin-film, metal alloy thermocouple junctions do not rectify, change circuit impedance only slightly, and require very little increase in space. Although they are less efficient cooling devices than semiconductor junctions, they may be applied to assist conventional cooling techniques for electronic devices

Visible emission from rare earth ions in nanocrystal-containing glasses

Abstract Rare earth-doped glasses are of great interest for their optical and fluorescence properties. However, phononmediated non-radiative transitions are a major obstacle to their use and the quantum efficiencies are sensitive to the environment of the rare earth ion. Recently, complex glasses containing fluorides have been developed in which fluoride crystallites can be made to form with a high solubility for rare earth ions. We have performed a study of the visible emission of Pr 3÷ in these glasses and have identified three groups of fluorescence lines coming from transitions between the P and the H levels. The phonons play an important role, both in up-conversion as well as in non-radiative decay between levels in these two sets. This effect is illustrated by the temperature dependence of the fluorescence spectra measured from 295 K to 4 K and for three different wavelengths, 514 nm, 488 nm and 476 nm in the quenched glasses and in the heat-treated or crystallite-containing glasses. Comparison of fluorescence spectra from glasses containing either pr3+/Y 3+ or pr3+/Gd 3+ also reveal an energy transfer between praseodymium that is increased by the presence of yttrium. © 1997 Elsevier Science B.V

Effects of Key2Teach on students' externalising and social-emotional problem behaviours, mediated by the teacher-student relationship

Teaching students with externalising problem behaviours is difficult for teachers, as it challenges the relationship that teachers engage in with their students. In this study, effects of Key2Teach on externalising and social-emotional problem behaviours and the mediating role of conflict in the teacher-student relationship were studied using a randomised controlled trial (RCT)-design. In two cohorts, 103 teacher-student dyads and peer-students (n = 1643) were assessed two times during a school year. Fifty-three dyads received the intervention (experimental group), whereas 50 dyads received no intervention (control group). Data were collected on teacher-reported externalising and social-emotional problem behaviours in students, and on teacher-student conflict. For dyad-students, results showed a direct effect of Key2Teach on conduct problems and an indirect effect, via teacher-student conflict, for hyperactivity problems. No effects on social-emotional problems were established. For peer-students, results showed indirect effects on externalising problems and direct effects on social-emotional problems. Implications for practice and future research are discussed

GHQ increases among Scottish 15 year olds 1987–2006

BACKGROUND: Increases in a number of psychosocial disorders have been identified among Western youth in the second half of the Twentieth century. However findings are not consistent, trends are complex, and comparisons over time are hampered by methodological problems. METHODS: Data were drawn from three samples identical in respect of age (15 years), school year (final year of statutory schooling) and geographical location (the West of Scotland). Each sample was administered the 12-item General Health Questionnaire, a measure of self-report psychological distress, in 1987 (N = 505), 1999 (N = 2,196) and 2006 (N = 3,194). Analyses were conducted to examine changes in: GHQ 'caseness'; individual items; and factors, derived via confirmatory factor analysis representing (a) 'negative' and 'positive' items, and (b) 'anxiety and depression', 'loss of confidence or self-esteem' and 'anhedonia and social dysfunction'. RESULTS: Based on the standard (2/3) cut-off, 'caseness' rates in 1987, 1999 and 2006 were 12.7, 15.1 and 21.5% (males) and 18.8, 32.5 and 44.1% (females). Similar increases were observed with more stringent 'caseness' cut-offs. Examination of individual items showed some to have increased much more markedly over time than others. There were larger increases among females for all except two items and some evidence, among both genders, of steeper increases among 'negative' items compared with 'positive' ones. However, the differences in slope were very small compared with the overall increases in both types. CONCLUSIONS: Data from three samples identical in respect of age, school year and geographical location, show marked increases in GHQ-12 'caseness' among females between 1987 and 1999 and among both males and females between 1999 and 2006. Although slightly steeper increases in 'negative' items raise the possibility that endorsing such symptoms may have become more acceptable, these were small in comparison with increases in all dimensions of psychological distress. The next step is to identify causal explanations for the increases reported here

Vulnerable warriors: the atmospheric marketing of military and policing equipment before and after 9/11

In this article, we analyse changes in the circulation of advertisements of policing products at security expos between 1995 and 2013. While the initial aim of the research was to evidence shifts in terrorist frames in the marketing of policing equipment before and after 9/11, our findings instead suggested that what we are seeing is the rise of marketing to police as “vulnerable warriors”, law enforcement officers in need of military weapons both for their offensive capabilities and for the protection they can offer to a police force that is always under threat

Relational legacies impacting on veteran transition from military to civilian life: trajectories of acquisition, loss and re-formulation of a sense of belonging

The veteran cohort has been inextricably linked in the general public's mind by media generated perceptions of high risk and fear of crime, echoed in wider contemporary debates linking issues of place, social identity, social exclusion (Pain 2000) and a loss of belonging in wider communities (Walklate 1998). Despite the growing interest in the longer term outcomes of transition from military to civilian life from policy-makers, practitioners and academics, few qualitative studies explore the social and relational impacts of this transitional experience on those who have experienced it. Tensions and frustrations expressed by ex-forces personnel, engaging in addictions services with a history of engagement in the criminal justice sector, are explored through the lens of belongingness, loss and related citizenship frameworks to expose temporal impacts on the acquisition, loss and reformulation of a sense of belonging across the life course. The relevance of a significant loss of belonging in the transition from military to civilian life is useful, given the widely accepted damaging consequences of having this need thwarted. This paper concludes that a broader understanding of this largely disenfranchised grief (Doka, 2002) can enable more informed reflexive opportunities to facilitate a valued military veteran citizenship status and thereby contribute to the formulation of current policy debates concerning the veteran question

Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis

Background Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy. Methods We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance. Results We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography. Conclusion Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data

Age and sex associate with outcome in older AML and high risk MDS patients treated with 10-day decitabine

Treatment choice according to the individual conditions remains challenging, particularly in older patients with acute myeloid leukemia (AML) and high risk myelodysplastic syndrome (MDS). The impact of performance status, comorbidities, and physical functioning on survival is not well defined for patients treated with hypomethylating agents. Here we describe the impact of performance status (14% ECOG performance status 2), comorbidity (40% HCT-comorbidity index ≥ 2), and physical functioning (41% short physical performance battery &lt; 9 and 17% ADL index &lt; 6) on overall survival (OS) in 115 older patients (age ≥ 66 years) treated on a clinical trial with a 10-day decitabine schedule. None of the patient-related variables showed a significant association with OS. Multivariable analysis revealed that age &gt; 76 years was significantly associated with reduced OS (HR 1.58; p = 0.043) and female sex was associated with superior OS (HR 0.62; p = 0.06). We further compared the genetic profiles of these subgroups. This revealed comparable mutational profiles in patients younger and older than 76 years, but, interestingly, revealed significantly more prevalent mutated ASXL1, STAG2, and U2AF1 in male compared to female patients. In this cohort of older patients treated with decitabine age and sex, but not comorbidities, physical functioning or cytogenetic risk were associated with overall survival.</p