245 research outputs found

    Landau theory and giant room-temperature barocaloric effect

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    The structural phase transitions of MF3 (M = Al, Cr, V, Fe, Ti, Sc) metal trifluorides are studied within a simple Landau theory consisting of tilts of rigid MF6 octahedra associated with soft antiferrodistortive optic modes that are coupled to long-wavelength strain generating acoustic phonons. We calculate the temperature and pressure dependence of several quantities such as the spontaneous distortions, volume expansion, and shear strains as well as T−P phase diagrams. By contrasting our model to experiments we quantify the deviations from mean-field behavior and find that the tilt fluctuations of the MF6 octahedra increase with metal cation size. We apply our model to predict giant barocaloric effects in Sc-substituted TiF3 of up to about 15JK−1kg−1 for modest hydrostatic compressions of 0.2GPa. The effect extends over a wide temperature range of over 140K (including room temperature) due to a large predicted rate, dTc/dP=723KGPa−1, which exceeds those of typical barocaloric materials. Our results suggest that open lattice frameworks such as the trifluorides are an attractive platform to search for giant barocaloric effects.Universidad de Costa Rica/[816-B5-22]/UCR/Costa RicaU.S. Department of Energy, Office of Basic Energy Sciences, Material Sciences and Engineering Division/[contract no. DE-AC02-06CH11357]//Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencia e Ingeniería de Materiales (CICIMA

    Growth or decline in the Church of England during the decade of Evangelism: did the Churchmanship of the Bishop matter?

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    The Decade of Evangelism occupied the attention of the Church of England throughout the 1990s. The present study employs the statistics routinely published by the Church of England in order to assess two matters: the extent to which these statistics suggest that the 43 individual dioceses finished the decade in a stronger or weaker position than they had entered it and the extent to which, according to these statistics, the performance of dioceses led by bishops shaped in the Evangelical tradition differed from the performance of dioceses led by bishops shaped in the Catholic tradition. The data demonstrated that the majority of dioceses were performing less effectively at the end of the decade than at the beginning, in terms of a range of membership statistics, and that the rate of decline varied considerably from one diocese to another. The only exception to the trend was provided by the diocese of London, which experienced some growth. The data also demonstrated that little depended on the churchmanship of the diocesan bishop in shaping diocesan outcomes on the performance indicators employed in the study

    Evangelical Christianity and Women’s Changing Lives

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    Women have outnumbered men as followers of Christianity at least since the transition to industrial capitalist modernity in the West. Yet developments in women's lives in relation to employment, family and feminist values are challenging their Christian religiosity. Building on a new strand of gender analysis in the sociology of religion, this article argues that gender is central to patterns of religiosity and secularization in the West. It then offers a case study of evangelical Christianity in England to illustrate how changes in women's lives are affecting their religiosity. Specifically, it argues that evangelical Christianity continues to be important among women occupying more traditional social positions (as wives and mothers), but adherence is declining among the growing number whose lives do not fit this older model

    Hyperspectral remote sensing of cyanobacterial pigments as indicators for cell populations and toxins in eutrophic lakes

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    The growth of mass populations of toxin-producing cyanobacteria is a serious concern for the ecological status of inland waterbodies and for human and animal health. In this study we examined the performance of four semi-analytical algorithms for the retrieval of chlorophyll a (Chl a) and phycocyanin (C-PC) from data acquired by the Compact Airborne Spectrographic Imager-2 (CASI-2) and the Airborne Imaging Spectrometer for Applications (AISA) Eagle sensor. The retrieval accuracies of the semi-analytical models were compared to those returned by optimally calibrated empirical band-ratio algorithms. The best-performing algorithm for the retrieval of Chl a was an empirical band-ratio model based on a quadratic function of the ratio of re!ectance at 710 and 670 nm (R2=0.832; RMSE=29.8%). However, this model only provided a marginally better retrieval than the best semi-analytical algorithm. The best-performing model for the retrieval of C-PC was a semi-analytical nested band-ratio model (R2=0.984; RMSE=3.98 mg m−3). The concentrations of C-PC retrieved using the semi-analytical model were correlated with cyanobacterial cell numbers (R2=0.380) and the particulate and total (particulate plus dissolved) pools of microcystins (R2=0.858 and 0.896 respectively). Importantly, both the empirical and semi-analytical algorithms were able to retrieve the concentration of C-PC at cyanobacterial cell concentrations below current warning thresholds for cyanobacteria in waterbodies. This demonstrates the potential of remote sensing to contribute to early-warning detection and monitoring of cyanobacterial blooms for human health protection at regional and global scales

    Microplastic study reveals the presence of natural and synthetic fibres in the diet of King Penguins (Aptenodytes patagonicus) foraging from South Georgia

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    The Antarctic Circumnavigation Expedition (ACE) was a research cruise of the Swiss Polar Institute, supported by funding from the ACE Foundation. Funding for this research was provided by the ACE Foundation (projects 5 and 19), the Natural Environment Research Council’s Collaborative Antarctic Science Scheme (CASS-129) and a Trans-Antarctic Association Grant to RBS.Marine ecosystems are experiencing substantial disturbances due to climate change and overfishing, and plastic pollution is an additional growing threat. Microfibres are among the most pervasive pollutants in the marine environment, including in the Southern Ocean. However, evidence for microfibre contamination in the diet of top predators in the Southern Ocean is rare. King Penguins (Aptenodytes patagonicus) feed on mesopelagic fish, which undergo diel vertical migrations towards the surface at night. Microfibres are concentrated in surface waters and sediments but can also be concentrated in fish, therefore acting as contamination vectors for diving predators feeding at depth. In this study, we investigate microfibre contamination of King Penguin faecal samples collected in February and March 2017 at South Georgia across three groups: incubating, chick-rearing and non-breeding birds. After a KOH digestion to dissolve the organic matter and a density separation step using a NaCl solution, the samples were filtered to collect microfibres. A total of 77% of the penguin faecal samples (36 of 47) contained microfibres. Fibres were measured and characterized using Fourier-Transform Infrared spectroscopy to determine their polymeric identity. Most fibres (88%) were made of natural cellulosic materials (e.g. cotton, linen), with only 12% synthetic (e.g. polyester, nylon) or semi-synthetic (e.g. rayon). An average of 21.9 ± 5.8 microfibres g−1 of faeces (lab dried mass) was found, with concentrations more than twice as high in incubating penguins than in penguins rearing chicks. Incubating birds forage further north at the Antarctic Polar Front and travel longer distances from South Georgia than chick-rearing birds. This suggests that long-distance travelling penguins are probably more exposed to the risk of ingesting microfibres when feeding north of the Antarctic Polar Front, which might act as a semi-permeable barrier for microfibres. Microfibres could therefore provide a signature for foraging location in King Penguins.Publisher PDFPeer reviewe

    No Consistent Simulated Trends in the Atlantic Meridional Overturning Circulation for the Past 6,000 Years

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    The Atlantic Meridional Overturning Circulation (AMOC) is a key feature of the North Atlantic with global ocean impacts. The AMOC's response to past changes in forcings during the Holocene provides important context for the coming centuries. Here, we investigate AMOC trends using an emerging set of transient simulations using multiple global climate models for the past 6,000 years. Although some models show changes, no consistent trend in overall AMOC strength during the mid-to-late Holocene emerges from the ensemble. We interpret this result to suggest no overall change in AMOC, which fits with our assessment of available proxy reconstructions. The decadal variability of the AMOC does not change in ensemble during the mid- and late-Holocene. There are interesting AMOC changes seen in the early Holocene, but their nature depends a lot on which inputs are used to drive the experiment

    The Land Suitability Rating System Is a Spatial Planning Tool to Assess Crop Suitability in Canada

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    The Land Suitability Rating System (LSRS) is a rule-based set of algorithms that integrate soil, climate and landscape factors to calculate a classed suitability rating for a given landscape to support commercial field crop production. The attributes used to define each of the factors are based on their proven ability to affect crop growth, their ability to be measured (or estimated by proxy) and their availability in accessible databases. The LSRS was first published in 1995 by Agriculture and Agri-Food Canada as a site-specific, manual calculator for spring-seeded small grains that incorporated sets of attribute point deduction curves based on expert knowledge. Since that time the system has been expanded to include additional crop modules and all data handling and calculations are automated through a set of web-based applications. The current version of LSRS (version 5) is implemented in Ruby on Rails® software as a suite of web services. The system runs against any soil map with standardized Canadian Soil Information Service soil data tables to process soil attributes and calculate limitations to crop growth. A climate factor rating is based on crop-specific agro-climatic indices and thresholds. Climatic indices have historically been calculated from 30-year climate normal periods using monthly data but LSRS can now also utilize daily data records which facilitate trend analyses within annual historic records. The use of available gridded climate datasets enables direct overlay and extraction of climate attributes to the spatial extent of soil map polygons. Lastly, the system incorporates a landscape factor related to land erodibility and constraints to management. Each of the three suitability factors is assigned a class rating between 1 (no limitations) and 7 (unsuitable) with the final overall rating being the most limiting of the three factors. Recent improvements in the ability of the system to process multiple climate datasets mean outputs from Global Circulation Models may also be useful for the LSRS model in assessing possible impacts of climate change on crop suitability. LSRS is used increasingly as a spatial research tool in assessing potential changes in crop distributions at both national and regional scales

    A randomised controlled trial of computerised cognitive behaviour therapy for the treatment of depression in primary care: the Randomised Evaluation of the Effectiveness and Acceptability of Computerised Therapy (REEACT) trial.

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    BACKGROUND: Computerised cognitive behaviour therapy (cCBT) has been developed as an efficient form of therapy delivery with the potential to enhance access to psychological care. Independent research is needed which examines both the clinical effectiveness and cost-effectiveness of cCBT over the short and longer term. OBJECTIVES: To compare the clinical effectiveness and cost-effectiveness of cCBT as an adjunct to usual general practitioner (GP) care against usual GP care alone, for a free-to-use cCBT program (MoodGYM; National Institute for Mental Health Research, Australian National University, Canberra, Australia) and a commercial pay-to-use cCBT program (Beating the Blues(®); Ultrasis, London, UK) for adults with depression, and to determine the acceptability of cCBT and the experiences of users. DESIGN: A pragmatic, multicentre, three-armed, parallel, randomised controlled trial (RCT) with concurrent economic and qualitative evaluations. Simple randomisation was used. Participants and researchers were not blind to treatment allocation. SETTING: Primary care in England. PARTICIPANTS: Adults with depression who scored ≥ 10 on the Patient Health Questionnaire-9 (PHQ-9). INTERVENTIONS: Participants who were randomised to either of the two intervention groups received cCBT (Beating the Blues or MoodGYM) in addition to usual GP care. Participants who were randomised to the control group were offered usual GP care. MAIN OUTCOME MEASURES: The primary outcome was depression at 4 months (PHQ-9). Secondary outcomes were depression at 12 and 24 months; measures of mental health and health-related quality of life at 4, 12 and 24 months; treatment preference; and the acceptability of cCBT and experiences of users. RESULTS: Clinical effectiveness: 210 patients were randomised to Beating the Blues, 242 patients were randomised to MoodGYM and 239 patients were randomised to usual GP care (total 691). There was no difference in the primary outcome (depression measured at 4 months) either between Beating the Blues and usual GP care [odds ratio (OR) 1.19, 95% confidence interval (CI) 0.75 to 1.88] or between MoodGYM and usual GP care (OR 0.98, 95% CI 0.62 to 1.56). There was no overall difference across all time points for either intervention compared with usual GP care in a mixed model (Beating the Blues versus usual GP care, p = 0.96; and MoodGYM versus usual GP care, p = 0.11). However, a small but statistically significant difference between MoodGYM and usual GP care at 12 months was found (OR 0.56, 95% CI 0.34 to 0.93). Free-to-use cCBT (MoodGYM) was not inferior to pay-to-use cCBT (Beating the Blues) (OR 0.91, 90% CI 0.62 to 1.34; p = 0.69). There were no consistent benefits of either intervention when secondary outcomes were examined. There were no serious adverse events thought likely to be related to the trial intervention. Despite the provision of regular technical telephone support, there was low uptake of the cCBT programs. Cost-effectiveness: cost-effectiveness analyses suggest that neither Beating the Blues nor MoodGYM appeared cost-effective compared with usual GP care alone. Qualitative evaluation: participants were often demotivated to access the computer programs, by reason of depression. Some expressed the view that a greater level of therapeutic input would be needed to promote engagement. CONCLUSIONS: The benefits that have previously been observed in developer-led trials were not found in this large pragmatic RCT. The benefits of cCBT when added to routine primary care were minimal, and uptake of this mode of therapy was relatively low. There remains a clinical and economic need for effective low-intensity psychological treatments for depression with improved patient engagement. TRIAL REGISTRATION: This trial is registered as ISRCTN91947481. FUNDING: This project was funded by the National Institute for Health Research Health Technology Assessment programme

    Large isotropic negative thermal expansion above a structural quantum phase transition

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    Perovskite structured materials contain myriad tunable ordered phases of electronic and magnetic origin with proven technological importance and strong promise for a variety of energy solutions. An always-contributing influence beneath these cooperative and competing interactions is the lattice, whose physics may be obscured in complex perovskites by the many coupled degrees of freedom, which makes these systems interesting. Here, we report signatures of an approach to a quantum phase transition very near the ground state of the nonmagnetic, ionic insulating, simple cubic perovskite material ScF3, and show that its physical properties are strongly effected as much as 100 K above the putative transition. Spatial and temporal correlations in the high-symmetry cubic phase determined using energy- and momentum-resolved inelastic x-ray scattering as well as x-ray diffraction reveal that soft mode, central peak, and thermal expansion phenomena are all strongly influenced by the transition.National Science Foundation Award No. DMR-1506825US Department of Energy, Office of Basic Energy Sciences under Contract No. DE- AC02-06CH11357Yale Prize Postdoctoral FellowshipNSF Grant No. DMR-0115852Universidad de Costa Rica. Vicerrectoría de Investigación Projecto No. 816-B5-220UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencia e Ingeniería de Materiales (CICIMA
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