6,272 research outputs found

    Developmental Dysplasia of the Hip

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    The results of compression forces applied to the isolated human calvaria

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    Data for the force necessary to fracture the isolated calvaria (skull cap) are not available in the extant literature. Twenty dry adult calvaria were tested to failure quasistatically at the vertex using a 15-kN load cell. The forces necessary to fracture or cause diastasis of calvarial sutures were then documented and gross examination of the specimens made. Failure forces had a mean measurement of 2772 N. Initial fractures did not cross suture lines. Prior to complete destruction of the calvaria there were 7 specimens in which all sutures of the calvaria became diastatic, 6 specimens in which the calvaria became diastatic along only the coronal sutures, 2 specimens in which the calvaria became diastatic along only the sagittal suture and 5 specimens in which there were diagonal linear parietal bone fractures. Our hopes are that these data may contribute to the structural design of more safer protective devices for use in our society, assist in predicting injury and aid in the construction of treatment paradigms

    High Resolution Spectroscopy of Two-Dimensional Electron Systems

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    Spectroscopic methods involving the sudden injection or ejection of electrons in materials are a powerful probe of electronic structure and interactions. These techniques, such as photoemission and tunneling, yield measurements of the "single particle" density of states (SPDOS) spectrum of a system. The SPDOS is proportional to the probability of successfully injecting or ejecting an electron in these experiments. It is equal to the number of electronic states in the system able to accept an injected electron as a function of its energy and is among the most fundamental and directly calculable quantities in theories of highly interacting systems. However, the two-dimensional electron system (2DES), host to remarkable correlated electron states such as the fractional quantum Hall effect, has proven difficult to probe spectroscopically. Here we present an improved version of time domain capacitance spectroscopy (TDCS) that now allows us to measure the SPDOS of a 2DES with unprecedented fidelity and resolution. Using TDCS, we perform measurements of a cold 2DES, providing the first direct measurements of the single-particle exchange-enhanced spin gap and single particle lifetimes in the quantum Hall system, as well as the first observations of exchange splitting of Landau levels not at the Fermi surface. The measurements reveal the difficult to reach and beautiful structure present in this highly correlated system far from the Fermi surface.Comment: There are formatting and minor textual differences between this version and the published version in Nature (follow the DOI link below

    Efficacy of personalized cognitive counseling in men of color who have sex with men: secondary data analysis from a controlled intervention trial.

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    In a previous report, we demonstrated the efficacy of a cognitively based counseling intervention compared to standard counseling at reducing episodes of unprotected anal intercourse (UAI) among men who have sex with men (MSM) seeking HIV testing. Given the limited number of efficacious prevention interventions for MSM of color (MOC) available, we analyzed the data stratified into MOC and whites. The sample included 196 white MSM and 109 MOC (23 African Americans, 36 Latinos, 22 Asians, eight Alaskan Natives/Native Americans/Hawaiian/Pacific Islander, and 20 of mixed or other unspecified race). Among MOC in the intervention group, the mean number of episodes of UAI declined from 5.1 to 1.6 at six months and was stable at 12 months (1.8). Among the MOC receiving standard counseling, the mean number of UAI episodes was 4.2 at baseline, 3.9 at six months and 2.1 at 12 months. There was a significant treatment effect overall (relative risk 0.59, 95% confidence interval 0.35-0.998). These results suggest that the intervention is effective in MOC

    Healthcare providers' views on the acceptability of financial incentives for breastfeeding:a qualitative study

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    BACKGROUND: Despite a gradual increase in breastfeeding rates, overall in the UK there are wide variations, with a trend towards breastfeeding rates at 6–8 weeks remaining below 40% in less affluent areas. While financial incentives have been used with varying success to encourage positive health related behaviour change, there is little research on their use in encouraging breastfeeding. In this paper, we report on healthcare providers’ views around whether using financial incentives in areas with low breastfeeding rates would be acceptable in principle. This research was part of a larger project looking at the development and feasibility testing of a financial incentive scheme for breastfeeding in preparation for a cluster randomised controlled trial. METHODS: Fifty–three healthcare providers were interviewed about their views on financial incentives for breastfeeding. Participants were purposively sampled to include a wide range of experience and roles associated with supporting mothers with infant feeding. Semi-structured individual and group interviews were conducted. Data were analysed thematically drawing on the principles of Framework Analysis. RESULTS: The key theme emerging from healthcare providers’ views on the acceptability of financial incentives for breastfeeding was their possible impact on ‘facilitating or impeding relationships’. Within this theme several additional aspects were discussed: the mother’s relationship with her healthcare provider and services, with her baby and her family, and with the wider community. In addition, a key priority for healthcare providers was that an incentive scheme should not impact negatively on their professional integrity and responsibility towards women. CONCLUSION: Healthcare providers believe that financial incentives could have both positive and negative impacts on a mother’s relationship with her family, baby and healthcare provider. When designing a financial incentive scheme we must take care to minimise the potential negative impacts that have been highlighted, while at the same time recognising the potential positive impacts for women in areas where breastfeeding rates are low
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