622 research outputs found

    Shubnikov de Haas effect in the metallic state of Na0.3_{0.3}CoO2_2

    Full text link
    Shubnikov de Haas oscillations for two well defined frequencies, corresponding respectively to areas of 0.8 and 1.36% of the first Brillouin zone (FBZ), were observed in single crystals of Na0.3_{0.3}CoO2_2. The existence of Na superstructures in Na0.3_{0.3}CoO2_2, coupled with this observation, suggests the possibility that the periods are due to the reconstruction of the large Fermi surface around the Γ\Gamma point. An alternative interpretation in terms of the long sought-after ϵg\epsilon_g^\prime pockets is also considered but found to be incompatible with existing specific heat data.Comment: 5 pages 4 figure

    Superconductivity in an organic insulator at very high magnetic fields

    Full text link
    We investigate by electrical transport the field-induced superconducting state (FISC) in the organic conductor λ\lambda-(BETS)2_2FeCl4_4. Below 4 K, antiferromagnetic-insulator, metallic, and eventually superconducting (FISC) ground states are observed with increasing in-plane magnetic field. The FISC state survives between 18 and 41 T, and can be interpreted in terms of the Jaccarino-Peter effect, where the external magnetic field {\em compensates} the exchange field of aligned Fe3+^{3+} ions. We further argue that the Fe3+^{3+} moments are essential to stabilize the resulting singlet, two-dimensional superconducting stateComment: 9 pages 3 figure

    A Digital Health Solution for Child Growth Monitoring at Home: Testing the Accuracy of a Novel “GrowthMonitor” Smartphone Application to Detect Abnormal Height and Body Mass Indices

    Get PDF
    Objective To develop and evaluate a smartphone application that accurately measures height and provides notifications when abnormalities are detected. Patients and Methods A total of 145 (75 boys) participants with a mean age ± SD of 8.7±4.5 years (range, 1.0-17.0 years), from the Children’s Hospital at Barts Health Trust, London, United Kingdom, were enrolled in the study. “GrowthMonitor” (UCL Creatives) iPhone application (GMA) measures height using augmented reality. Using population-based (UK-WHO) references, algorithms calculated height SD score (HSDS), distance from target height (THSDSDEV), and HSDS change over time (ΔHSDS). Pre-established thresholds discriminated normal/abnormal growth. The GMA and a stadiometer (Harpenden; gold standard) measured standing heights of children at routine clinic visits. A subset of parents used GMA to measure their child’s height at home. Outcome targets were 95% of GMA measurements within ±0.5 SDS of the stadiometer and the correct identification of abnormal HSDS, THSDSDEV, and ΔHSDS. Results Bland-Altman plots revealed no appreciable bias in differences between paired study team GMA and stadiometer height measurements, with a mean of the differences of 0.11 cm with 95% limits of agreement of −2.21 to 2.42 cm. There was no evidence of greater bias occurring for either shorter/younger children or taller/older children. The 2 methods of measurements were highly correlated (R=0.999). GrowthMonitor iPhone application measurements performed by parents in clinic and at home were slightly less accurate. The κ coefficient indicated reliable and consistent agreement of flag alerts for HSDS (κ=0.74) and THSDSDEV (κ=0.88) between 83 paired GMA and stadiometer measurements. GrowthMonitor iPhone application yielded a detection rate of 96% and 97% for HSDS-based and THSDSDEV-based red flags, respectively. Forty-two (18 boys) participants had GMA calculated ΔHSDS using an additional height measurement 6-16 months later, and no abnormal flag alerts were triggered for ΔHSDS values. Conclusion GrowthMonitor iPhone application provides the potential for parents/carers and health care professionals to capture serial height measurements at home and without specialized equipment. Reliable interpretation and flagging of abnormal measurements indicate the potential of this technology to transform childhood growth monitoring

    Nonmedical prescription drug use among US young adults by educational attainment

    Get PDF
    Purpose: Little is known about nonmedical use of prescription drugs among non-college-attending young adults in the United States. Methods: Data were drawn from 36,781 young adults (ages 18–22 years) from the 2008–2010 National Survey on Drug Use and Health public use files. The adjusted main effects for current educational attainment, along with its interaction with gender and race/ethnicity, were considered. Results: Compared to those attending college, non-college-attending young adults with at least and less than a HS degree had a higher prevalence of past-year nonmedical use of prescription opioids [NMUPO 13.1 and 13.2 %, respectively, vs. 11.3 %, adjusted odds ratios (aORs) 1.21 (1.11–1.33) and 1.25 (1.12–1.40)], yet lower prevalence of prescription stimulant use. Among users, regardless of drug type, non-college-attending youth were more likely to have past-year disorder secondary to use [e.g., NMUPO 17.4 and 19.1 %, respectively, vs. 11.7 %, aORs 1.55 (1.22–1.98) and 1.75 (1.35–2.28)]. Educational attainment interacted with gender and race: (1) among nonmedical users of prescription opioids, females who completed high school but were not enrolled in college had a significantly greater risk of opioid disorder (compared to female college students) than the same comparison for men; and (2) the risk for nonmedical use of prescription opioids was negligible across educational attainment groups for Hispanics, which was significantly different than the increased risk shown for non-Hispanic whites. Conclusions: There is a need for young adult prevention and intervention programs to target nonmedical prescription drug use beyond college campuses

    The Wow Factor? A Comparative Study of the Development of Student Music Teachers' Talents in Scotland and Australia

    Get PDF
    For some time there has been debate about differing perspectives on musical gift and musical intelligence. One view is that musical gift is innate: that it is present in certain individuals from birth and that the task of the teacher is to develop the potential which is there. A second view is that musical gift is a complex concept which includes responses from individuals to different environments and communities (Howe and Sloboda, 1997). This then raises the possibility that musical excellence can be taught. We have already explored this idea with practising musicians (Stollery and McPhee, 2002). Our research has now expanded to include music teachers in formation, and, in this paper, we look at the influences in their musical development which have either 'crystallised' or 'paralysed' the musical talent which they possess. Our research has a comparative dimension, being carried out in Scotland and in Australia. We conclude that there are several key influences in the musical development of the individual, including home and community support, school opportunities and teaching styles and that there may be education and culture-specific elements to these influences

    Caspase-3 and caspase-8 expression in breast cancer: caspase-3 is associated with survival

    Get PDF
    Impaired apoptosis is one of the hallmarks of cancer. Caspase-3 and -8 are key regulators of the apoptotic response and have been shown to interact with the calpain family, a group of cysteine proteases, during tumorigenesis. The current study sought to investigate the prognostic potential of caspase-3 and -8 in breast cancer, as well as the prognostic value of combinatorial caspase and calpain expression. A large cohort (n = 1902) of early stage invasive breast cancer patients was used to explore the expression of caspase-3 and -8. Protein expression was examined using standard immunohistochemistry on tissue microarrays. High caspase-3 expression, but not caspase-8, is significantly associated with adverse breast cancer-specific survival (P = 0.008 and P = 0.056, respectively). Multivariate analysis showed that caspase-3 remained an independent factor when confounding factors were included (hazard ratio (HR) 1.347, 95% confidence interval (CI) 1.086–1.670; P = 0.007). The analyses in individual subgroups demonstrated the significance of caspase-3 expression in clinical outcomes in receptor positive (ER, PR or HER2) subgroups (P = 0.001) and in non-basal like subgroup (P = 0.029). Calpain expression had been previously assessed. Significant association was also found between high caspase-3/high calpain-1 and breast cancer-specific survival in the total patient cohort (P = 0.005) and basal-like subgroup (P = 0.034), as indicated by Kaplan–Meier analysis. Caspase-3 expression is associated with adverse breast cancer-specific survival in breast cancer patients, and provides additional prognostic values in distinct phenotypes. Combinatorial caspase and calpain expression can predict worse prognosis, especially in basal-like phenotypes. The findings warrant further validation studies in independent multi-centre patient cohorts
    corecore