230 research outputs found

    Materials and structures

    Get PDF
    Materials and structures technology covers a wide range of technical areas. Some of the most pertinent issues for the Astrotech 21 missions include dimensionally stable structural materials, advanced composites, dielectric coatings, optical metallic coatings for low scattered light applications, low scattered light surfaces, deployable and inflatable structures (including optical), support structures in 0-g and 1-g environments, cryogenic optics, optical blacks, contamination hardened surfaces, radiation hardened glasses and crystals, mono-metallic telescopes and instruments, and materials characterization. Some specific examples include low coefficients of thermal expansion (CTE) structures (0.01 ppm/K), lightweight thermally stable mirror materials, thermally stable optical assemblies, high reliability/accuracy (1 micron) deployable structures, and characterization of nanometer level behavior of materials/structures for interferometry concepts. Large filled-aperture concepts will require materials with CTE's of 10(exp 9) at 80 K, anti-contamination coatings, deployable and erectable structures, composite materials with CTE's less than 0.01 ppm/K and thermal hysteresis, 0.001 ppm/K. Gravitational detection systems such as LAGOS will require rigid/deployable structures, dimensionally stable components, lightweight materials with low conductivity, and high stability optics. The Materials and Structures panel addressed these issues and the relevance of the Astrotech 21 mission requirements by dividing materials and structures technology into five categories. These categories, the necessary development, and applicable mission/program development phasing are summarized. For each of these areas, technology assessments were made and development plans were defined

    Applying valence framing to enhance the effect of information on transport-related carbon dioxide emissions

    Get PDF
    The provision of information about transport-related carbon dioxide (CO2) emissions to the traveler can be seen as an instrument to increase the likelihood of more sustainable choices being made by individuals. However, as transport-related CO2 emissions are largely seen as a 'social' cost rather than a 'private' cost to the individual, the behavioral engagement with and response to information on environmental effects of travel choices may be limited. It is argued that framing, studied in a range of contexts, can be used to enhance the evaluation of choice attributes and promote more sustainable choices. An experiment is reported that examines the effect of valence framing of amounts of CO2 emissions on the perceived differences between alternative amounts. Through the use of positive and negative terms, the information is framed to focus attention either on the potential of a travel mode to provide environmental benefit (positive frame) or on its potential to reduce environmental loss (negative frame). Survey participants' estimates of CO2 amounts were compared for positive and negative framing of the same information using an ordered logit model. The findings imply that negative framing is more effective than positive framing in highlighting differences between CO2 amounts of alternative travel modes and therefore is likely to influence travel-related choices. © 2012 Elsevier Ltd

    Connected clusters: landscaping study

    Get PDF
    This study presents evidence from five dynamic, city region-based climate innovation clusters. Here businesses, academics, communities and government work together to deliver low-carbon innovation. We believe this concentration of resources, expertise and initiative is our best chance of meeting the Paris climate targets while also reaping social and economic benefits that come with the development and delivery of cleantech solutions. Climate-KIC’s ConnectedClusters project is an alliance of five city regions – Birmingham, Edinburgh, Frankfurt, London and Valencia – committed to sharing, replicating and scaling what works in developing innovation ecosystems for delivering effective climate action. Between now and 2020, the project will work hard to accelerate and enable transformation of the places we live into clean, prosperous and thriving cities and regions by developing new collaborative approaches to technology, procurement, investment and training. ConnectedClusters will help inform a transition away from product and technology innovation in isolation, towards a systemic, regionally-embedded approach to climate innovation. Paris shows that for our continued prosperity, transformation on a scale never witnessed before is imperative. Only by working together can we achieve that change

    High-Contrast Observations in Optical and Infrared Astronomy

    Full text link
    High-contrast observations in optical and infrared astronomy are defined as any observation requiring a technique to reveal a celestial object of interest that is in such close angular proximity to another source brighter by a factor of at least 10^5 that optical effects hinder or prevent the collection of photons directly from the target of observation. This is a relatively new type of observation that enables research on previously obscured parts of the Universe. In particular, it is most applicable to Comparative Planetary Science, a field that directly attacks such questions as "how common are planetary systems? What types of planets exist, and are there planets other than Earth that are capable of supporting life as we know it?" We survey the scientific motivations for high-contrast observations, provide an overview of the techniques currently being used or developed, and discuss some ideas and studies for future prospects.Comment: In press for Annual Review of Astronomy and Astrophysics (Vol. 47). 46 pages, 15 figure

    A Selective Interplay between Aberrant EPSPKA and INaP Reduces Spike Timing Precision in Dentate Granule Cells of Epileptic Rats

    Get PDF
    Spike timing precision is a fundamental aspect of neuronal information processing in the brain. Here we examined the temporal precision of input–output operation of dentate granule cells (DGCs) in an animal model of temporal lobe epilepsy (TLE). In TLE, mossy fibers sprout and establish recurrent synapses on DGCs that generate aberrant slow kainate receptor–mediated excitatory postsynaptic potentials (EPSPKA) not observed in controls. We report that, in contrast to time-locked spikes generated by EPSPAMPA in control DGCs, aberrant EPSPKA are associated with long-lasting plateaus and jittered spikes during single-spike mode firing. This is mediated by a selective voltage-dependent amplification of EPSPKA through persistent sodium current (INaP) activation. In control DGCs, a current injection of a waveform mimicking the slow shape of EPSPKA activates INaP and generates jittered spikes. Conversely in epileptic rats, blockade of EPSPKA or INaP restores the temporal precision of EPSP–spike coupling. Importantly, EPSPKA not only decrease spike timing precision at recurrent mossy fiber synapses but also at perforant path synapses during synaptic integration through INaP activation. We conclude that a selective interplay between aberrant EPSPKA and INaP severely alters the temporal precision of EPSP–spike coupling in DGCs of chronic epileptic rats

    Pediatric immunization-related safety incidents in primary care: A mixed methods analysis of a national database.

    Get PDF
    Background: Children are scheduled to receive 18–20 immunizations before their 18th birthday in England and Wales; this approximates to 13 million vaccines administered per annum. Each immunization represents a potential opportunity for immunization-related error and effective immunization is imperative to maintain the public health benefit from immunization. Using data from a national reporting system, this study aimed to characterize pediatric immunization-related safety incident reports from primary care in England and Wales between 2002 and 2013. Methods: A cross-sectional mixed methods study was undertaken. This comprised reading the free-text of incident reports and applying codes to describe incident type, potential contributory factors, harm severity, and incident outcomes. A subsequent thematic analysis was undertaken to interpret the most commonly occurring codes, such as those describing the incident, events leading up to it and reported contributory factors, within the contexts they were described. Results: We identified 1745 reports and most (n = 1077, 61.7%) described harm outcomes including three deaths, 67 reports of moderate harm and 1007 reports of low harm. Failure of timely vaccination was the potential cause of three child deaths from meningitis and pneumonia, and described in a further 113 reports. Vaccine administration incidents included the wrong number of doses (n = 476, 27.3%), wrong timing (n = 294, 16.8%), and wrong vaccine (n = 249, 14.3%). Documentation failures were frequently implicated. Socially and medically vulnerable children were commonly described. Conclusion: This is the largest examination of reported contributory factors for immunization-related patient safety incidents in children. Our findings suggest investments in IT infrastructure to support data linkage and identification of risk predictors, development of consultation models that promote the role of parents in mitigating safety incidents, and improvement efforts to adapt and adopt best practices from elsewhere, are needed to mitigate future immunization-related patient safety incidents. These priorities are particularly pressing for vulnerable patient groups.8 page(s

    Disentangling Income Inequality and the Redistributive Effect of Social Transfers and Taxes in 36 LIS Countries

    Full text link

    Endogenous Zinc in Neurological Diseases

    Get PDF
    The use of zinc in medicinal skin cream was mentioned in Egyptian papyri from 2000 BC (for example, the Smith Papyrus), and zinc has apparently been used fairly steadily throughout Roman and modern times (for example, as the American lotion named for its zinc ore, 'Calamine'). It is, therefore, somewhat ironic that zinc is a relatively late addition to the pantheon of signal ions in biology and medicine. However, the number of biological functions, health implications and pharmacological targets that are emerging for zinc indicate that it might turn out to be 'the calcium of the twenty-first century'. Here neurobiological roles of endogenous zinc is summarized

    Towards an Embodied Sociology of War

    Get PDF
    While sociology has historically not been a good interlocutor of war, this paper argues that the body has always known war, and that it is to the corporeal that we can turn in an attempt to develop a language to better speak of its myriad violences and its socially generative force. It argues that war is a crucible of social change that is prosecuted, lived and reproduced via the occupation and transformation of myriad bodies in numerous ways from exhilaration to mutilation. War and militarism need to be traced and analysed in terms of their fundamental, diverse and often brutal modes of embodied experience and apprehension. This paper thus invites sociology to extend its imaginative horizon to rethink the crucial and enduring social institution of war as a broad array of fundamentally embodied experiences, practices and regimes
    corecore