78 research outputs found

    Monte Carlo Electron Trajectory Calculations of Electron Interactions in Samples with Special Geometries

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    Implementing a Monte Carlo simulation for application to electron sample interactions requires use of accurate treatments of elastic and inelastic scattering. In formulating a Monte Carlo simulation, careful testing must be carried out to ensure that the calculation yields sensible and useful results. A suitable testing procedure includes calculation of (1) electron backscatter coefficients as a function of atomic number, including any necessary adjustment of scattering parameters; (2) backscatter coefficients as a function of specimen tilt; (3) backscatter and transmission coefficients for thin foils; (4) backscattered electron energy distributions; (5) electron spatial distributions; and (6) x-rays, including x-ray depth distributions, and relative and absolute yields. Adapting a Monte Carlo simulation to a particular problem involving special sample geometry requires careful consideration of the interaction of the electron with the target. When the electron trajectory crosses a boundary, the segments of the trajectory in each phase must be calculated in a logical, stepwise fashion, allowing for modification of the step lengths due to variable scattering power in phases of different composition. The particular example of a planar boundary between phases of different composition is considered

    Microstructure and mineral composition of dystrophic calcification associated with the idiopathic inflammatory myopathies

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    This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This work was supported in part by the intramural research programs of NIEHS (FWM, LGR) and NIDCR (PGR), ADAF (NE), NIST (NE, JS), the Medical Research Council, UK (AB through the provision of the facility for the determination of mineralization density at the microscopic scale from BSE imaging) and the Veterinary Advisory Committee of the Horserace Betting Levy Board, UK (AB via support of M Arora)

    AESOPS: a randomised controlled trial of the clinical effectiveness and cost-effectiveness of opportunistic screening and stepped care interventions for older hazardous alcohol users in primary care

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    BACKGROUND: There is clear evidence of the detrimental impact of hazardous alcohol consumption on the physical and mental health of the population. Estimates suggest that hazardous alcohol consumption annually accounts for 150,000 hospital admissions and between 15,000 and 22,000 deaths in the UK. In the older population, hazardous alcohol consumption is associated with a wide range of physical, psychological and social problems. There is evidence of an association between increased alcohol consumption and increased risk of coronary heart disease, hypertension and haemorrhagic and ischaemic stroke, increased rates of alcohol-related liver disease and increased risk of a range of cancers. Alcohol is identified as one of the three main risk factors for falls. Excessive alcohol consumption in older age can also contribute to the onset of dementia and other age-related cognitive deficits and is implicated in one-third of all suicides in the older population. OBJECTIVE: To compare the clinical effectiveness and cost-effectiveness of a stepped care intervention against a minimal intervention in the treatment of older hazardous alcohol users in primary care. DESIGN: A multicentre, pragmatic, two-armed randomised controlled trial with an economic evaluation. SETTING: General practices in primary care in England and Scotland between April 2008 and October 2010. PARTICIPANTS: Adults aged ≥ 55 years scoring ≥ 8 on the Alcohol Use Disorders Identification Test (10-item) (AUDIT) were eligible. In total, 529 patients were randomised in the study. INTERVENTIONS: The minimal intervention group received a 5-minute brief advice intervention with the practice or research nurse involving feedback of the screening results and discussion regarding the health consequences of continued hazardous alcohol consumption. Those in the stepped care arm initially received a 20-minute session of behavioural change counselling, with referral to step 2 (motivational enhancement therapy) and step 3 (local specialist alcohol services) if indicated. Sessions were recorded and rated to ensure treatment fidelity. MAIN OUTCOME MEASURES: The primary outcome was average drinks per day (ADD) derived from extended AUDIT--Consumption (3-item) (AUDIT-C) at 12 months. Secondary outcomes were AUDIT-C score at 6 and 12 months; alcohol-related problems assessed using the Drinking Problems Index (DPI) at 6 and 12 months; health-related quality of life assessed using the Short Form Questionnaire-12 items (SF-12) at 6 and 12 months; ADD at 6 months; quality-adjusted life-years (QALYs) (for cost-utility analysis derived from European Quality of Life-5 Dimensions); and health and social care resource use associated with the two groups. RESULTS: Both groups reduced alcohol consumption between baseline and 12 months. The difference between groups in log-transformed ADD at 12 months was very small, at 0.025 [95% confidence interval (CI)--0.060 to 0.119], and not statistically significant. At month 6 the stepped care group had a lower ADD, but again the difference was not statistically significant. At months 6 and 12, the stepped care group had a lower DPI score, but this difference was not statistically significant at the 5% level. The stepped care group had a lower SF-12 mental component score and lower physical component score at month 6 and month 12, but these differences were not statistically significant at the 5% level. The overall average cost per patient, taking into account health and social care resource use, was £488 [standard deviation (SD) £826] in the stepped care group and £482 (SD £826) in the minimal intervention group at month 6. The mean QALY gains were slightly greater in the stepped care group than in the minimal intervention group, with a mean difference of 0.0058 (95% CI -0.0018 to 0.0133), generating an incremental cost-effectiveness ratio (ICER) of £1100 per QALY gained. At month 12, participants in the stepped care group incurred fewer costs, with a mean difference of -£194 (95% CI -£585 to £198), and had gained 0.0117 more QALYs (95% CI -0.0084 to 0.0318) than the control group. Therefore, from an economic perspective the minimal intervention was dominated by stepped care but, as would be expected given the effectiveness results, the difference was small and not statistically significant. CONCLUSIONS: Stepped care does not confer an advantage over minimal intervention in terms of reduction in alcohol consumption at 12 months post intervention when compared with a 5-minute brief (minimal) intervention. TRIAL REGISTRATION: This trial is registered as ISRCTN52557360. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 25. See the HTA programme website for further project information

    The Effectiveness of Alcohol Screening and Brief Intervention in Emergency Departments: A Multicentre Pragmatic Cluster Randomized Controlled Trial

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    BACKGROUND: Alcohol misuse is common in people attending emergency departments (EDs) and there is some evidence of efficacy of alcohol screening and brief interventions (SBI). This study investigated the effectiveness of SBI approaches of different intensities delivered by ED staff in nine typical EDs in England: the SIPS ED trial. METHODS AND FINDINGS: Pragmatic multicentre cluster randomized controlled trial of SBI for hazardous and harmful drinkers presenting to ED. Nine EDs were randomized to three conditions: a patient information leaflet (PIL), 5 minutes of brief advice (BA), and referral to an alcohol health worker who provided 20 minutes of brief lifestyle counseling (BLC). The primary outcome measure was the Alcohol Use Disorders Identification Test (AUDIT) status at 6 months. Of 5899 patients aged 18 or more presenting to EDs, 3737 (63·3%) were eligible to participate and 1497 (40·1%) screened positive for hazardous or harmful drinking, of whom 1204 (80·4%) gave consent to participate in the trial. Follow up rates were 72% (n?=?863) at six, and 67% (n?=?810) at 12 months. There was no evidence of any differences between intervention conditions for AUDIT status or any other outcome measures at months 6 or 12 in an intention to treat analysis. At month 6, compared to the PIL group, the odds ratio of being AUDIT negative for brief advice was 1·103 (95% CI 0·328 to 3·715). The odds ratio comparing BLC to PIL was 1·247 (95% CI 0·315 to 4·939). A per protocol analysis confirmed these findings. CONCLUSIONS: SBI is difficult to implement in typical EDs. The results do not support widespread implementation of alcohol SBI in ED beyond screening followed by simple clinical feedback and alcohol information, which is likely to be easier and less expensive to implement than more complex interventions

    Language and reading impairments are associated with increased prevalence of non-right handedness

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    Funding: Royal Society - UF150663, RGF\EA\180141; Wellcome Trust - 217065/Z/19/Z; H2020 European Research Council - 694189; NWO - 451-15-017; National Health and Medical Research Council - 1173896; Canadian Institute for Health Research - MOP-133440.Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (Ncases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.Publisher PDFPeer reviewe

    Genome-wide analyses of individual differences in quantitatively assessed reading- and language-related skills in up to 34,000 people

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    The use of spoken and written language is a fundamental human capacity. Individual differences in reading- and language-related skills are influenced by genetic variation, with twin-based heritability estimates of 30 to 80% depending on the trait. The genetic architecture is complex, heterogeneous, and multifactorial, but investigations of contributions of single-nucleotide polymorphisms (SNPs) were thus far underpowered. We present a multicohort genome-wide association study (GWAS) of five traits assessed individually using psychometric measures (word reading, nonword reading, spelling, phoneme awareness, and nonword repetition) in samples of 13,633 to 33,959 participants aged 5 to 26 y. We identified genome-wide significant association with word reading (rs11208009, P = 1.098 × 10−8) at a locus that has not been associated with intelligence or educational attainment. All five reading-/language-related traits showed robust SNP heritability, accounting for 13 to 26% of trait variability. Genomic structural equation modeling revealed a shared genetic factor explaining most of the variation in word/nonword reading, spelling, and phoneme awareness, which only partially overlapped with genetic variation contributing to nonword repetition, intelligence, and educational attainment. A multivariate GWAS of word/nonword reading, spelling, and phoneme awareness maximized power for follow-up investigation. Genetic correlation analysis with neuroimaging traits identified an association with the surface area of the banks of the left superior temporal sulcus, a brain region linked to the processing of spoken and written language. Heritability was enriched for genomic elements regulating gene expression in the fetal brain and in chromosomal regions that are depleted of Neanderthal variants. Together, these results provide avenues for deciphering the biological underpinnings of uniquely human traits

    Genome-wide analyses of individual differences in quantitatively assessed reading- and language-related skills in up to 34,000 people

    Get PDF
    The use of spoken and written language is a fundamental human capacity. Individual differences in reading- and language-related skills are influenced by genetic variation, with twin-based heritability estimates of 30 to 80% depending on the trait. The genetic architecture is complex, heterogeneous, and multifactorial, but investigations of contributions of single-nucleotide polymorphisms (SNPs) were thus far underpowered. We present a multicohort genome-wide association study (GWAS) of five traits assessed individually using psychometric measures (word reading, nonword reading, spelling, phoneme awareness, and nonword repetition) in samples of 13,633 to 33,959 participants aged 5 to 26 y. We identified genome-wide significant association with word reading (rs11208009, P = 1.098 × 10-8) at a locus that has not been associated with intelligence or educational attainment. All five reading-/language-related traits showed robust SNP heritability, accounting for 13 to 26% of trait variability. Genomic structural equation modeling revealed a shared genetic factor explaining most of the variation in word/nonword reading, spelling, and phoneme awareness, which only partially overlapped with genetic variation contributing to nonword repetition, intelligence, and educational attainment. A multivariate GWAS of word/nonword reading, spelling, and phoneme awareness maximized power for follow-up investigation. Genetic correlation analysis with neuroimaging traits identified an association with the surface area of the banks of the left superior temporal sulcus, a brain region linked to the processing of spoken and written language. Heritability was enriched for genomic elements regulating gene expression in the fetal brain and in chromosomal regions that are depleted of Neanderthal variants. Together, these results provide avenues for deciphering the biological underpinnings of uniquely human traits

    Hypothesis-driven genome-wide association studies provide novel insights into genetics of reading disabilities

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    Peer reviewe

    Genome-wide analyses of individual differences in quantitatively assessed reading- and language-related skills in up to 34,000 people

    Get PDF
    The use of spoken and written language is a fundamental human capacity. Individual differences in reading- and language-related skills are influenced by genetic variation, with twin-based heritability estimates of 30 to 80% depending on the trait. The genetic architecture is complex, heterogeneous, and multifactorial, but investigations of contributions of single-nucleotide polymorphisms (SNPs) were thus far underpowered. We present a multicohort genome-wide association study (GWAS) of five traits assessed individually using psychometric measures (word reading, nonword reading, spelling, phoneme awareness, and nonword repetition) in samples of 13,633 to 33,959 participants aged 5 to 26 y. We identified genome-wide significant association with word reading (rs11208009, P = 1.098 x 10(-8)) at a locus that has not been associated with intelligence or educational attainment. All five reading-/language-related traits showed robust SNP heritability, accounting for 13 to 26% of trait variability. Genomic structural equation modeling revealed a shared genetic factor explaining most of the variation in word/nonword reading, spelling, and phoneme awareness, which only partially overlapped with genetic variation contributing to nonword repetition, intelligence, and educational attainment. A multivariate GWAS of word/nonword reading, spelling, and phoneme awareness maximized power for follow-up investigation. Genetic correlation analysis with neuroimaging traits identified an association with the surface area of the banks of the left superior temporal sulcus, a brain region linked to the processing of spoken and written language. Heritability was enriched for genomic elements regulating gene expression in the fetal brain and in chromosomal regions that are depleted of Neanderthal variants. Together, these results provide avenues for deciphering the biological underpinnings of uniquely human traits.Peer reviewe
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