2,533 research outputs found

    Community norms, opinion leadership and innovativeness among truck growers

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    Readout technologies for directional WIMP Dark Matter detection

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    The measurement of the direction of WIMP-induced nuclear recoils is a compelling but technologically challenging strategy to provide an unambiguous signature of the detection of Galactic dark matter. Most directional detectors aim to reconstruct the dark-matter-induced nuclear recoil tracks, either in gas or solid targets. The main challenge with directional detection is the need for high spatial resolution over large volumes, which puts strong requirements on the readout technologies. In this paper we review the various detector readout technologies used by directional detectors. In particular, we summarize the challenges, advantages and drawbacks of each approach, and discuss future prospects for these technologies

    Discovery of 36 eclipsing EL CVn binaries found by the Palomar Transient Factory

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    We report the discovery and analysis of 36 new eclipsing EL CVn-type binaries, consisting of a core helium-composition pre-white dwarf and an early-type main-sequence companion, more than doubling the known population of these systems. We have used supervised machine learning methods to search 0.8 million lightcurves from the Palomar Transient Factory, combined with SDSS, Pan-STARRS and 2MASS colours. The new systems range in orbital periods from 0.46-3.8 d and in apparent brightness from ~14-16 mag in the PTF RR or gg^{\prime} filters. For twelve of the systems, we obtained radial velocity curves with the Intermediate Dispersion Spectrograph at the Isaac Newton Telescope. We modelled the lightcurves, radial velocity curves and spectral energy distributions to determine the system parameters. The radii (0.3-0.7 R\mathrm{R_{\odot}}) and effective temperatures (8000-17000 K) of the pre-He-WDs are consistent with stellar evolution models, but the masses (0.12-0.28 M\mathrm{M_{\odot}}) show more variance than models predicted. This study shows that using machine learning techniques on large synoptic survey data is a powerful way to discover substantial samples of binary systems in short-lived evolutionary stages

    Family life cycle disruption in rural communities: The case of the Lake Shelbyville reservoir

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    This project assessed on an ex post facto basis selected impacts upon families and individuals due to the land acquisition program associated with the construction of the Shelbyville Reservoir in east-central Illinois begun in 1962. Research focused on Okaw Township, which borders Lake Shelbyville to the west in Shelby County. The in-depth, individual and family case studies indicated that farm family businesses are not the products of a single generation, or a single family. They are intimately tied to the intergenerational land transfer process which occurs among interconnected families living in close proximity. Thus, the time perspective in examining changes brought about by land acquisition and relocation must be extended on the generational level if the full range of impacts on the local cultural ecology is to be represented. Areawide changes in the availability and price of land made the difficult task of reestablishing a family farm even harder for selected families. The Corps' land acquisition policies in 1962 did not consider the generations involved in the establishment of family farms. Furthermore, local residents were critical of the Corps' policies and personnel during the land acquisition process. That historical complaint summarized by the quote, "the Corps is not a good neighbor," has even today hindered the Corps' ability to manage its relations with area residents and local government units. An understanding of the personal and family lifecycle perspectives on local cultural ecology, coupled with an appreciation of the degree to which rural social processes are bound in time, can strengthen State of Illinois comprehensive planning, decision-making, and review procedures for water and related resource development.U.S. Department of the InteriorU.S. Geological SurveyOpe

    Rapid "Turn-on" of type 1 AGN in a quiescent early type galaxy SDSS1115+0544

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    We present a detailed study of a transient in the center of SDSS1115+0544 based on the extensive UV, optical, mid-IR light curves (LC) and spectra over 1200 days. The host galaxy is a quiescent early type galaxy at zz = 0.0899 with a blackhole mass of 2×107M2\times10^7M_\odot. The transient underwent a 2.5 magnitude brightening over 120\sim120 days, reaching a peak VV-band luminosity (extinction corrected) of 20.9-20.9 magnitude, then fading 0.5 magnitude over 200 days, settling into a plateau of >600>600 days. Following the optical brightening are the significant mid-IR flares at 3.43.4 and 4.5μ4.5\mum, with a peak time delay of 180\sim180 days. The mid-IR LCs are explained as the echo of UV photons by a dust medium with a radius of 5×10175\times10^{17} cm, consistent with E(BV)\rm E(B-V) of 0.58 inferred from the spectra. This event is very energetic with an extinction corrected Lbol4×1044L_{bol} \sim 4\times10^{44} erg s1^{-1}. Optical spectra over 400 days in the plateau phase revealed newly formed broad Hα,β\alpha, \beta emission with a FWHM of 3750\sim3750 km s1^{-1} and narrow coronal lines such as [Fe VII], [Ne V]. This flare also has a steeply rising UV continuum, detected by multi-epoch SwiftSwift data at +700+700 to +900+900 days post optical peak. The broad Balmer lines and the UV continuum do not show significant temporal variations. The slow evolving LCs over 1200 days, the constant Balmer lines and UV continuum at late-times rule out TDE and SN IIn as the physical model for this event. We propose that this event is a `turn-on' AGN, transitioning from a quiescent state to a type 1 AGN with a sub-Eddington accretion rate of 0.017M0.017M_\odot/yr. This change occurred on a very short time scale of 120200\sim 120- 200 days. The discovery of such a rapid `turn-on' AGN poses challenges to accretion disk theories and may indicate such event is not extremely rare.Comment: Comments are welcome. Emails to the first author. Accepted for publication in Ap

    Folic acid induces cell type-specific changes in the transcriptome of breast cancer cell lines: a proof-of-concept study

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    The effect of folic acid (FA) on breast cancer (BC) risk is uncertain. We hypothesised that this uncertainty may be due, in part, to differential effects of FA between BC cells with different phenotypes. To test this we investigated the effect of treatment with FA concentrations within the range of unmetabolised FA reported in humans on the expression of the transcriptome of non-transformed (MCF10A) and cancerous (MCF7 and Hs578T) BC cells. The total number of transcripts altered was MCF10A 75 (70 up-regulated), MCF7 24 (14 up-regulated) and Hs578T 328 (156 up-regulated). Only the cancer-associated gene TAGLN was altered by FA in all three cell lines. In MCF10A and Hs578T cells, FA treatment decreased pathways associated with apoptosis, cell death and senescence, but increased those associated with cell proliferation. The folate transporters SLC19A1, SLC46A1 and FOLR1 were differentially expressed between cell lines tested. However, the level of expression was not altered by FA treatment. These findings suggest that physiological concentrations of FA can induce cell type-specific changes in gene regulation in a manner that is consistent with proliferative phenotype. This has implications for understanding the role of FA in BC risk. In addition, these findings support the suggestion the differences in gene expression induced by FA may involve differential activities of folate transporters. Together these findings indicate the need for further studies of the effect of FA on BC

    Association between high dietary intake of the n-3 polyunsaturated fatty acid docosahexaenoic acid and reduced risk of Crohn's disease

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    Background: There are plausible mechanisms for how dietary docosahexaenoic acid (DHA), an n−3 polyunsaturated fatty acid, could prevent Crohn's disease (CD). Aim: To conduct a prospective study to investigate the association between increased intake of DHA and risk of CD. Methods: Overall, 229 702 participants were recruited from nine European centres between 1991 and 1998. At recruitment, dietary intakes of DHA and fatty acids were measured using validated food frequency questionnaires. The cohort was monitored through to June 2004 to identify participants who developed incident CD. In a nested case–control analysis, each case was matched with four controls; odds ratios (ORs) were calculated for quintiles of DHA intake, adjusted for total energy intake, smoking, other dietary fatty acids, dietary vitamin D and body mass index. Results: Seventy-three participants developed incident CD. All higher quintiles of DHA intake were inversely associated with development of CD; the highest quintile had the greatest effect size (OR = 0.07; 95% CI = 0.02–0.81). The OR trend across quintiles of DHA was 0.54 (95% CI = 0.30–0.99, Ptrend = 0.04). Including BMI in the multivariate analysis, due to its correlation with dietary fat showed similar associations. There were no associations with the other dietary fatty acids studied. Conclusion: There were inverse associations, with a biological gradient between increasing dietary docosahexaenoic acid intakes and incident Crohn's disease. Further studies in other populations should measure docosahexaenoic acid to determine if the association is consistent and the hypothesis tested in randomised controlled trials of purely docosahexaenoic acid supplementation

    Fat and carbohydrate intake over three generations modify growth, metabolism and cardiovascular phenotype in female mice in an age-related manner

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    Environmental challenges such as a high fat diet during pregnancy can induce changes in offspring growth, metabolism and cardiovascular function. However, challenges that are sustained over several generations can induce progressive compensatory metabolic adjustments in young adults. It is not known if such effects persist during ageing. We investigated whether diets with different fat and carbohydrate contents over three generations modifies markers of ageing. Female C57BL/6 F0 mice were fed diets containing 5% or 21% fat (w/w) throughout pregnancy and lactation. Female offspring were fed the same diet as their dams until the F3 generation. In each generation, body weight, 24-hour food intake were recorded weekly, and plasma metabolites were measured by colorimetric assays, blood pressure by tail cuff plethysmography and vasoconstriction by myography on postnatal day 90 or 456. There was little effect of diet or generation on phenotypic markers in day 90 adults. There was a significant increase in whole body, liver and heart weight with ageing (d456) in the F3 21% fat group compared to the F1 and F3 5% groups. Fasting plasma glucose concentration was significantly increased with ageing in the 5% group in the F3 generation and in the 21% group in both generations. There was a significant effect of diet and generation on ex-vivo vasoconstriction in ageing females. Differences in dietary fat may induce metabolic compensation in young adults that persist over three generations. However, such compensatory effects decline during ageing
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