871 research outputs found

    Photoheliograph study for the Apollo telescope mount

    Get PDF
    Photoheliograph study for Apollo telescope moun

    From source to sink in central Gondwana: Exhumation of the Precambrian basement rocks of Tanzania and sediment accumulation in the adjacent Congo basin

    Get PDF
    Apatite fission track (AFT) and (U-Th)/He (AHe) thermochronometry data are reported and used to unravel the exhumation history of crystalline basement rocks from the elevated (>1000 m above sea level) but low-relief Tanzanian Craton. Coeval episodes of sedimentation documented within adjacent Paleozoic to Mesozoic basins of southern Tanzania and the Congo basin of the Democratic Republic of Congo indicate that most of the cooling in the basement rocks in Tanzania was linked to erosion. Basement samples were from an exploration borehole located within the craton and up to 2200 m below surface. Surface samples were also analyzed. AFT dates range between 317 ± 33 Ma and 188 ± 44 Ma. Alpha (Ft)-corrected AHe dates are between 433 ± 24 Ma and 154 ± 20 Ma. Modeling of the data reveals two important periods of cooling within the craton: one during the Carboniferous-Triassic (340–220 Ma) and a later, less well constrained episode, during the late Cretaceous. The later exhumation is well detected proximal to the East African Rift (70 Ma). Thermal histories combined with the estimated geothermal gradient of 9°C/km constrained by the AFT and AHe data from the craton and a mean surface temperature of 20°C indicate removal of up to 9 ± 2 km of overburden since the end of Paleozoic. The correlation of erosion of the craton and sedimentation and subsidence within the Congo basin in the Paleozoic may indicate regional flexural geodynamics of the lithosphere due to lithosphere buckling induced by far-field compressional tectonic processes and thereafter through deep mantle upwelling and epeirogeny tectonic processes

    Effects of Frontal Transcranial Direct Current Stimulation on Emotional State and Processing in Healthy Humans

    Get PDF
    The prefrontal cortex is involved in mood and emotional processing. In patients suffering from depression, the left dorsolateral prefrontal cortex (DLPFC) is hypoactive, while activity of the right DLPFC is enhanced. Counterbalancing these pathological excitability alterations by repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS) improves mood in these patients. In healthy subjects, however, rTMS of the same areas has no major effect, and the effects of tDCS are mixed. We aimed to evaluate the effects of prefrontal tDCS on emotion and emotion-related cognitive processing in healthy humans. In a first study, we administered excitability-enhancing anodal, excitability-diminishing cathodal, and placebo tDCS to the left DLPFC, combined with antagonistic stimulation of the right frontopolar cortex, and tested acute emotional changes by an adjective checklist. Subjective emotions were not influenced by tDCS. Emotional face identification, however, which was explored in a second experiment, was subtly improved by a tDCS-driven excitability modulation of the prefrontal cortex, markedly by anodal tDCS of the left DLPFC for positive emotional content. We conclude that tDCS of the prefrontal cortex improves emotion processing in healthy subjects, but does not influence subjective emotional state

    Modular DSLs for flexible analysis: An e-Motions reimplementation of Palladio

    Get PDF
    We address some of the limitations for extending and validating MDE-based implementations of NFP analysis tools by presenting a modular, model-based partial reimplementation of one well-known analysis framework, namely the Palladio Architecture Simulator. We specify the key DSLs from Palladio in the e-Motions system, describing the basic simulation semantics as a set of graph transformation rules. Di erent properties to be analysed are then encoded as separate, parametrised DSLs, independent of the de nition of Palladio. These can then be composed with the base Palladio DSL to generate speci c simulation environments. Models created in the Palladio IDE can be fed directly into this simulation environment for analysis. We demonstrate two main benefits of our approach: 1) The semantics of the simulation and the nonfunctional properties to be analysed are made explicit in the respective DSL speci cations, and 2) because of the compositional de nition, we can add de nitions of new non-functional properties and their analyses.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    The effect of calcium palmitate on bacteria associated with infant gut microbiota

    Get PDF
    Abstract Gut microbiota development in formula‐fed and breast‐fed infants is known to differ. This could relate to the usage of unmodified vegetable oil instead of mammalian fat in infant formula (IF), causing the enhanced formation of the poorly soluble soap calcium palmitate (CP) in the infant's gut. Here we investigate in vitro the possible influence of CP on the infant gut bacteria. The growth of several bacterial species dominant in the infant's gut was analyzed by culturing in media with CP. Faecalibacterium prausnitzii as a sensitive representative was analyzed in detail by scanning transmission electron microscopy, membrane staining, gas chromatography, and microbial fuel cell experiments. Of all bacteria tested, the growth of several bifidobacteria and F. prausnitzii was reduced at 0.01 mg/ml CP, Bifidobacterium infantis stopped growing completely. CP reduced the cell envelope thickness of F. prausnitzii, disturbed the cell membrane fatty acids and function of membrane proteins involved in electron transport. CP inhibited the growth of bifidobacteria and faecalibacteria. This suggests that modification of fat in IF may benefit the development of the gut microbiota in formula‐fed infants by supporting the colonization of important beneficial bacteria in early life. Future clinical studies are needed to confirm this

    A qualitative study of Autistic adults' quality of life during the COVID-19 pandemic and lockdowns

    Get PDF
    Background: Autistic people experience higher rates of most mental health conditions and report more difficulties with change than nonautistic people. As such, the periods of national stay-at-home orders (known in the United Kingdom as a “lockdown”) endured since the beginning of the COVID-19 (coronavirus disease 2019) pandemic in March 2020 may have been particularly challenging for autistic people. Aim: This study explored autistic adults' experience of quality of life and well-being during the start of the COVID-19 pandemic (specifically March to August 2020) using open-text responses from an online survey. Methods: In total, 79 autistic adults from the United Kingdom (aged 21–75 years) took part. Participants completed an online survey, including open-text questions on how various factors influencing quality of life, such as social interactions, general health, well-being, and sensory experiences, were impacted by the COVID-19 pandemic and the first set of national lockdowns that occurred between March and August 2020. Results: Thematic analysis created four key themes, each illustrated by several subthemes. These four themes explore (1) health, (2) social changes, (3) support provisions, and (4) adopting new routines. Many participants discussed the impact that the COVID-19 pandemic and the first set of national lockdowns had on their health and expressed concerns regarding the transition out of periods of lockdown, including readjusting to new rules, going back to in-person interactions, and reacclimatizing to high-stimulation sensory environments. However, several participants reported positive experiences of the periods of lockdown, such as reduced commuting, more control over sensory environments, and more time to pursue personal interests and self-care. Conclusions: These findings highlight the importance of giving autistic individuals the support they need to transition back to “normality” as COVID-19 becomes endemic

    Autism in England: assessing underdiagnosis in a population- based cohort study of prospectively collected primary care data

    Get PDF
    Background: Autism has long been viewed as a paediatric condition, meaning that many autistic adults missed out on a diagnosis as children when autism was little known. We estimated numbers of diagnosed and undiagnosed autistic people in England, and examined how diagnostic rates differed by socio-demographic factors. Methods: This population-based cohort study of prospectively collected primary care data from IQVIA Medical Research Data (IMRD) compared the prevalence of diagnosed autism to community prevalence to estimate underdiagnosis. 602,433 individuals registered at an English primary care practice in 2018 and 5,586,100 individuals registered between 2000 and 2018 were included. Findings: Rates of diagnosed autism in children/young people were much higher than in adults/older adults. As of 2018, 2.94% of 10- to 14-year-olds had a diagnosis (1 in 34), vs. 0.02% aged 70+ (1 in 6000). Exploratory projections based on these data suggest that, as of 2018, 463,500 people (0.82% of the English population) may have been diagnosed autistic, and between 435,700 and 1,197,300 may be autistic and undiagnosed (59–72% of autistic people, 0.77%–2.12% of the English population). Age-related inequalities were also evident in new diagnoses (incidence): c.1 in 250 5- to 9-year-olds had a newly-recorded autism diagnosis in 2018, vs. c.1 in 4000 20- to 49-year-olds, and c.1 in 18,000 people aged 50+. Interpretation: Substantial age-related differences in the proportions of people diagnosed suggest an urgent need to improve access to adult autism diagnostic services. Funding: Dunhill Medical Trust, Economic and Social Research Council, Medical Research Council, National Institute for Health Research, the Wellcome Trust, and the Royal College of Psychiatrists.</p

    Phylogenetic and molecular analysis of hydrogen-producing green algae

    Get PDF
    A select set of microalgae are reported to be able to catalyse photobiological H2 production from water. Based on the model organism Chlamydomonas reinhardtii, a method was developed for the screening of naturally occurring H2-producing microalgae. By purging algal cultures with N2 in the dark and subsequent illumination, it is possible to rapidly induce photobiological H2 evolution. Using NMR spectroscopy for metabolic profiling in C. reinhardtii, acetate, formate, and ethanol were found to be key compounds contributing to metabolic variance during the assay. This procedure can be used to test algal species existing as axenic or mixed cultures for their ability to produce H2. Using this system, five algal isolates capable of H2 production were identified in various aquatic systems. A phylogenetic tree was constructed using ribosomal sequence data of green unicellular algae to determine if there were taxonomic patterns of H2 production. H2-producing algal species were seen to be dispersed amongst most clades, indicating an H2-producing capacity preceded evolution of the phylum Chlorophyta
    corecore