1,211 research outputs found

    Patterned probes for high precision 4D-STEM bragg measurements.

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    Nanoscale strain mapping by four-dimensional scanning transmission electron microscopy (4D-STEM) relies on determining the precise locations of Bragg-scattered electrons in a sequence of diffraction patterns, a task which is complicated by dynamical scattering, inelastic scattering, and shot noise. These features hinder accurate automated computational detection and position measurement of the diffracted disks, limiting the precision of measurements of local deformation. Here, we investigate the use of patterned probes to improve the precision of strain mapping. We imprint a "bullseye" pattern onto the probe, by using a binary mask in the probe-forming aperture, to improve the robustness of the peak finding algorithm to intensity modulations inside the diffracted disks. We show that this imprinting leads to substantially improved strain-mapping precision at the expense of a slight decrease in spatial resolution. In experiments on an unstrained silicon reference sample, we observe an improvement in strain measurement precision from 2.7% of the reciprocal lattice vectors with standard probes to 0.3% using bullseye probes for a thin sample, and an improvement from 4.7% to 0.8% for a thick sample. We also use multislice simulations to explore how sample thickness and electron dose limit the attainable accuracy and precision for 4D-STEM strain measurements

    Target marketing can help attract city residents

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    While suburban growth continues, city living is regaining popularity. It is common knowledge that urban neighborhoods often attract young, single professionals, but a more precise identification of potential city dwellers could help cities understand and develop their comparative advantages. Now, perhaps more than ever, cities need to know which people want to live in them and how their vision of urban life may be accommodated by public policy. A common concern expressed among urban mayors is that the quality of their city services, especially schools, stacks up poorly against that of most suburbs. Improving public education is often cited as the key to attracting suburbanites to cities. Enhancing school quality is indeed an important element in any urban revitalization effort, but it may be less critical than is commonly assumed. Consider that households made up of married couples with children under 18 now account for only a quarter of the nation\u27s total, down from 4 in 10 households in 1970

    Association between STI and child sexual exploitation in children under 16 years old attending sexual health clinics in England: findings from a case–control study.

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    OBJECTIVE: Child sexual exploitation (CSE) can be difficult to identify, as there may be few reliable indicators. Although they may be used in decision-making, there is no evidence that STIs are predictors of CSE. We investigated the relationship between STI presentation at sexual health clinics (SHCs) and CSE. METHODS: SHCs with 18 or more children aged 13-15 years old with STI diagnoses in 2012 were identified using the Genitourinary Medicine Clinic Activity Data Set STI Surveillance System. Cases with confirmed bacterial or protozoal STIs were matched by age, gender and clinic with non-STI controls. Lead clinicians were asked to complete an online questionnaire on CSE-related risk factors of cases and controls irrespective of STI presence. Associations between STI outcome and CSE-related risk factors were analysed using conditional logistic regression. RESULTS: Data were provided on 466 children aged 13-15 years old; 414 (89%) were female, 340 (80%) were aged 15, 108 (23%) were aged 14, and 18 (3.9%) were aged 13 years. In matched univariate analysis, an STI diagnosis was significantly associated with 'highly-likely/confirmed' CSE (OR 3.87, p=0.017) and safeguarding concerns (OR 1.94, p=0.022). Evidence of an association between STI diagnosis and 'highly-likely/confirmed' CSE persisted after adjustment for partner numbers and prior clinic attendance (OR 3.85, p=0.053). CONCLUSION: Presentation with bacterial or protozoal STIs in children aged 13-15 years old at SHCs may be considered a potential marker for CSE. It would be prudent to consider CSE, indepth assessment and potential referral for any children under 16 years old presenting with a bacterial or protozoal STI

    Temporal Gene Expression Profiling during Rat Femoral Marrow Ablation-Induced Intramembranous Bone Regeneration

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    Enhanced understanding of differential gene expression and biological pathways associated with distinct phases of intramembranous bone regeneration following femoral marrow ablation surgery will improve future advancements regarding osseointegration of joint replacement implants, biomaterials design, and bone tissue engineering. A rat femoral marrow ablation model was performed and genome-wide microarray data were obtained from samples at 1, 3, 5, 7, 10, 14, 28, and 56 days post-ablation, with intact bones serving as controls at Day 0. Bayesian model-based clustering produced eight distinct groups amongst 9,062 significant gene probe sets based on similar temporal expression profiles, which were further categorized into three major temporal classes of increased, variable, and decreased expression. Osteoblastic- and osteoclastic-associated genes were found to be significantly expressed within the increased expression groups. Chondrogenesis was not detected histologically. Adipogenic marker genes were found within variable/decreased expression groups, emphasizing that adipogenesis was inhibited during osteogenesis. Differential biological processes and pathways associated with each major temporal group were identified, and significantly expressed genes involved were visually represented by heat maps. It was determined that the increased expression group exclusively contains genes involved in pathways for matrix metalloproteinases (MMPs), Wnt signaling, TGF-β signaling, and inflammatory pathways. Only the variable expression group contains genes associated with glycolysis and gluconeogenesis, the notch signaling pathway, natural killer cell mediated cytotoxicity, and the B cell receptor signaling pathway. The decreased group exclusively consists of genes involved in heme biosynthesis, the p53 signaling pathway, and the hematopoietic cell lineage. Significant biological pathways and transcription factors expressed at each time point post-ablation were also identified. These data present the first temporal gene expression profiling analysis of the rat genome during intramembranous bone regeneration induced by femoral marrow ablation

    The failure of suicide prevention in primary care: family and GP perspectives - a qualitative study

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    Background Although Primary care is crucial for suicide prevention, clinicians tend to report completed suicides in their care as non-preventable. We aimed to examine systemic inadequacies in suicide prevention from the perspectives of bereaved family members and GPs.Methods Qualitative study of 72 relatives or close friends bereaved by suicide and 19 General Practitioners who have experienced the suicide of patients.Results Relatives highlight failures in detecting symptoms and behavioral changes and the inability of GPs to understand the needs of patients and their social contexts. A perceived overreliance on anti-depressant treatment is a major source of criticism by family members. GPs tend to lack confidence in the recognition and management of suicidal patients, and report structural inadequacies in service provision.Conclusions Mental health and primary care services must find innovative and ethical ways to involve families in the decision-making process for patients at risk of suicide

    Mothers of Soldiers in Wartime: A National News Narrative

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    National news media represent mothers of US combat soldiers in the Iraq War as archetypal good mothers, that is, mothers who continue their maternal work even after their children are deployed. However, not all mothers are depicted as the archetypal patriotic mother, i.e., a good mother who is also stoic and silent about the war and her child\u27s role in it. Mothers of soldiers are portrayed as good mothers who sometimes also voice their attitudes about the war effort. The maternal attitudes ranged from complete support for the war to opposition to the war but support for the soldiers. The findings suggest a picture of wartime motherhood that is more nuanced than the historical image of the patriotic mother suggests

    High-resolution temporal profiling of transcripts during Arabidopsis leaf senescence reveals a distinct chronology of processes and regulation

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    Leaf senescence is an essential developmental process that impacts dramatically on crop yields and involves altered regulation of thousands of genes and many metabolic and signaling pathways, resulting in major changes in the leaf. The regulation of senescence is complex, and although senescence regulatory genes have been characterized, there is little information on how these function in the global control of the process. We used microarray analysis to obtain a highresolution time-course profile of gene expression during development of a single leaf over a 3-week period to senescence. A complex experimental design approach and a combination of methods were used to extract high-quality replicated data and to identify differentially expressed genes. The multiple time points enable the use of highly informative clustering to reveal distinct time points at which signaling and metabolic pathways change. Analysis of motif enrichment, as well as comparison of transcription factor (TF) families showing altered expression over the time course, identify clear groups of TFs active at different stages of leaf development and senescence. These data enable connection of metabolic processes, signaling pathways, and specific TF activity, which will underpin the development of network models to elucidate the process of senescence

    Associations between adverse childhood experiences, attitudes towards COVID-19 restrictions and vaccine hesitancy: a cross-sectional study

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    Objectives Adverse childhood experiences (ACEs) can affect life-course health and well-being, including risk-taking behaviour and trust. This study explored associations between ACEs and trust in health information on COVID-19, attitudes towards and compliance with COVID-19 restrictions and vaccine hesitancy. Design National cross-sectional telephone survey using a sample of landline and mobile numbers stratified by Health Board, deprivation quintile and age group. Setting Households in Wales during national COVID-19 restrictions (December 2020 to March 2021). Participants 2285 Welsh residents aged ≥18 years. Measures Nine ACEs; low trust in National Health Service (NHS) COVID-19 information; supporting removal of social distancing and mandatory face coverings; breaking COVID-19 restrictions; and vaccine hesitancy (rejection or uncertainty of vaccination). Results Increasing ACE counts were independently related to low trust in NHS COVID-19 information, feeling unfairly restricted by government and ending mandatory face coverings. High ACE counts (4+ vs 0 ACEs) were also associated with supporting removal of social distancing. Breaking COVID-19 restrictions increased with ACE count with likelihood doubling from no ACEs to 4+ ACEs. Vaccine hesitancy was threefold higher with 4+ ACEs (vs 0 ACEs) and higher in younger age groups. Thus, modelled estimates of vaccine hesitancy ranged from 3.42% with no ACEs, aged ≥70 years, to 38.06% with 4+ ACEs, aged 18–29 years. Conclusions ACEs are common across populations of many countries. Understanding how they impact trust in health advice and uptake of medical interventions could play a critical role in the continuing response to COVID-19 and controlling future pandemics. Individuals with ACEs suffer greater health risks throughout life and may also be excluded from interventions that reduce infection risks. While pandemic responses should consider how best to reach those suffering from ACEs, longer term, better compliance with public health advice is another reason to invest in safe and secure childhoods for all children

    Spatial contrast sensitivity in adolescents with autism spectrum disorders

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    Adolescents with autism spectrum disorders (ASD) and typically developing (TD) controls underwent a rigorous psychophysical assessment that measured contrast sensitivity to seven spatial frequencies (0.5-20 cycles/degree). A contrast sensitivity function (CSF) was then fitted for each participant, from which four measures were obtained: visual acuity, peak spatial frequency, peak contrast sensitivity, and contrast sensitivity at a low spatial frequency. There were no group differences on any of the four CSF measures, indicating no differential spatial frequency processing in ASD. Although it has been suggested that detail-oriented visual perception in individuals with ASD may be a result of differential sensitivities to low versus high spatial frequencies, the current study finds no evidence to support this hypothesis
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