52 research outputs found

    Challenges in Ceramic Science: A Report from the Workshop on Emerging Research Areas in Ceramic Science

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    In March 2012, a group of researchers met to discuss emerging topics in ceramic science and to identify grand challenges in the field. By the end of the workshop, the group reached a consensus on eight challenges for the future:—understanding rare events in ceramic microstructures, understanding the phase-like behavior of interfaces, predicting and controlling heterogeneous microstructures with unprecedented functionalities, controlling the properties of oxide electronics, understanding defects in the vicinity of interfaces, controlling ceramics far from equilibrium, accelerating the development of new ceramic materials, and harnessing order within disorder in glasses. This paper reports the outcomes of the workshop and provides descriptions of these challenges

    Wide field camera observations of Baade's Window

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    We have observed a field in Baade's Window using the Wide Field Camera of the Hubble Space Telescope (HST) and obtain V- and /-band photometry down to V~22.5. These data go several magnitudes fainter than previously obtained from the ground. The location of the break in the luminosity function suggests that there are a significant number of intermediate age ( < 10 Gyr) stars in the Galactic bulge. This conclusion rests on the assumptions that the extinction towards our field is similar to that seen in other parts of Baade's Window, that the distance to the bulge is approximately 8 kpc, and that we can determine fairly accurate zero points for the HST photometry. Changes in any one of these assumptions could increase the inferred age, but a conspiracy oflower reddening, a shorter distance to the bulge, and/or photometric zero-point errors would be needed to imply a population entirely older than 10 Gyr. We infer an initial mass function slope for the main-sequence stars, and find that it is consistent with that measured in the solar neighborhood; unfortunately, the slope is poorly constrained because we sample only a narrow range of stellar mass and because of uncertainties in the observed luminosity function at the faint end

    Reduction of PG:1115+080 Images

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    The data are three exposures in PC6 through F785LP obtained on March 3, 1991. The exposure times are 120, 400, and 400 seconds. The data are reduced with the "standard" WFPC reduction scheme: A-to-D correction, DC bias subtraction, AC bias subtraction, dark current subtraction, preflash subtraction, and flat field normalization, using the best available calibration data. The exposures are combined into a weighted average normalized to 400 seconds exposure time, so one DN (data number) is about 17.25 electrons. At this step, cosmic rays are removed by intercomparison of the three images

    The genetic architecture of the human cerebral cortex

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    The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

    Genome-wide structural variant analysis identifies risk loci for non-Alzheimer’s dementias

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    We characterized the role of structural variants, a largely unexplored type of genetic variation, in two non-Alzheimer’s dementias, namely Lewy body dementia (LBD) and frontotemporal dementia (FTD)/amyotrophic lateral sclerosis (ALS). To do this, we applied an advanced structural variant calling pipeline (GATK-SV) to short-read whole-genome sequence data from 5,213 European-ancestry cases and 4,132 controls. We discovered, replicated, and validated a deletion in TPCN1 as a novel risk locus for LBD and detected the known structural variants at the C9orf72 and MAPT loci as associated with FTD/ALS. We also identified rare pathogenic structural variants in both LBD and FTD/ALS. Finally, we assembled a catalog of structural variants that can be mined for new insights into the pathogenesis of these understudied forms of dementia

    Genome sequencing analysis identifies new loci associated with Lewy body dementia and provides insights into its genetic architecture

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    The genetic basis of Lewy body dementia (LBD) is not well understood. Here, we performed whole-genome sequencing in large cohorts of LBD cases and neurologically healthy controls to study the genetic architecture of this understudied form of dementia, and to generate a resource for the scientific community. Genome-wide association analysis identified five independent risk loci, whereas genome-wide gene-aggregation tests implicated mutations in the gene GBA. Genetic risk scores demonstrate that LBD shares risk profiles and pathways with Alzheimer's disease and Parkinson's disease, providing a deeper molecular understanding of the complex genetic architecture of this age-related neurodegenerative condition

    Coping and Ego Depletion: Recovery After the Coping Process

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    In this chapter, we combine a new approach to the self with a traditional, standard idea about coping in order to understand the coping process. The central idea is that many operations of the self involve the consumption of a limited resource. This resource is used in volition (e.g., choice, responsible decision-making, and active responses) and self-control. Stress makes severe demands on this resource, because people must engage in active responding and must regulate themselves so as to adapt to difficult circumstances. One major consequence of stress is that the resource becomes depleted. This will impair the person\u27s functioning across a broad spectrum of activities. For the person to recover, therefore, this resource must be replenished . Although it has been recognized previously that coping with stress consumes resources (e.g., 1, 2, 3, 4), our analysis differs in that it offers more in-depth insight into the nature of this resource

    The short-term safety and efficacy of fluoxetine in depressed adolescents with alcohol and cannabis use disorders: a pilot randomized placebo-controlled trial

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    Abstract Background The objective of this study was to examine whether fluoxetine was superior to placebo in the acute amelioration of depressive symptomatology in adolescents with depressive illness and a comorbid substance use disorder. Methods Eligible subjects ages 12–17 years with either a current major depressive disorder (MDD) or a depressive disorder that were also suffering from a comorbid substance-related disorder were randomized to receive either fluoxetine or placebo in this single site, 8-week double-blind, placebo-controlled study. The primary outcome analysis was a random effects mixed model for repeated measurements of Children's Depression Rating Scale-Revised (CDRS-R) scores compared between treatment groups across time. Results An interim analysis was performed after 34 patients were randomized. Based on the results of a futility analysis, study enrollment was halted. Twenty-nine males and 5 females were randomized to receive fluoxetine (n = 18) or placebo (n = 16). Their mean age was 16.5 (1.1) years. Overall, patients who received fluoxetine and placebo had a reduction in CDRS-R scores. However, there was no significant difference in mean change in CDRS-R total score in those subjects treated with fluoxetine and those who received placebo (treatment difference = 0.19, S.E. = 0.58, F = 0.14, p = .74). Furthermore, there was not a significant difference in rates of positive urine drug toxicology results between treatment groups at any post-randomization visit (F = 0.22, df = 1, p = 0.65). The main limitation of this study is its modest sample size and resulting low statistical power. Other significant limitations to this study include, but are not limited to, the brevity of the trial, high placebo response rate, limited dose range of fluoxetine, and the inclusion of youth who met criteria for depressive disorders other than MDD. Conclusion Fluoxetine was not superior to placebo in alleviating depressive symptoms or in decreasing rates of positive drug screens in the acute treatment of adolescents with depression and a concomitant substance use disorder.</p

    Dosing Strategies for Lithium Monotherapy in Children and Adolescents with Bipolar I Disorder

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    OBJECTIVE: The primary goal of this exploratory study was to obtain data that could lead to evidence-based dosing strategies for lithium in children and adolescents suffering from bipolar I disorder. METHODS: Outpatients aged 7-17 years meeting Diagnostic and Statistical Manual of Mental Disorders, 4th edition, diagnostic criteria for bipolar I disorder (manic or mixed) were eligible for 8 weeks of open label treatment with lithium in one of three dosing arms. In Arm I, participants began treatment at a dose of 300 mg of lithium twice daily. The starting dose of lithium in Arms II and III was 300 mg thrice daily. Patients in Arms I and II could have their dose increased by 300 mg/day, depending on clinical response, at weekly visits. Patients in Arm III also had mid-week telephone interviews after which they could also have their dose of lithium increased by 300 mg per day. Youths weighing I, whereas youths weighing \u3e/=30 kg were randomly assigned to Arm I, II, or III. Randomization was balanced by age (7-11 years, 12-17 years) and sex in approximately equal numbers. A priori response criteria were defined as a Clinical Global Impressions-Improvement scale score of /= 50% improvement in Young Mania Rating Scale score, and more than half of the patients (58%) achieved response. Overall, lithium was well tolerated. All three treatment arms had similar effectiveness, side effect profiles, and tolerability of lithium. CONCLUSIONS: On the basis of these results, a dosing strategy in which pediatric patients begin lithium at a dose of 300 mg thrice daily (with an additional 300 mg increase during the first week), followed by 300 mg weekly increases until a priori stopping criteria are met, will be used in an upcoming randomized, placebo-controlled trial
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