623 research outputs found

    The Spatial Variability of Turbulence above a Forest

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    Evaluation of European Land Data Assimilation System (ELDAS) products using in site observations

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    Three land-surface models with land-data assimilation scheme (DA) were evaluated for one growing season using in situ observations obtained across Europe. To avoid drifts in the land-surface state in the models, soil moisture corrections are derived from errors in screen-level atmospheric quantities. With the in situ data it is assessed whether these land-surface schemes produce adequate results regarding the annual range of the soil water content, the monthly mean soil moisture content in the root zone and evaporative fraction (the ratio of evapotranspiration to energy available at the surface). DA considerably reduced bias in net precipitation, while slightly reducing RMSE as well. Evaporative fraction was improved in dry conditions but was hardly affected in moist conditions. The amplitude of soil moisture variations tended to be underestimated. The impact of improved land-surface properties like Leaf Area Index, water holding capacity and rooting depth may be as large as corrections of the DA systems. Because soil moisture memorizes errors in the hydrological cycle of the models, DA will remain necessary in forecast mode. Model improvements should be balanced against improvements of DA per se. Model bias appearing from persistent analysis increments arising from DA systems should be addressed by model improvement

    Thickness dependence of the resistivity of Platinum group metal thin films

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    We report on the thin film resistivity of several platinum-group metals (Ru, Pd, Ir, Pt). Platinum-group thin films show comparable or lower resistivities than Cu for film thicknesses below about 5\,nm due to a weaker thickness dependence of the resistivity. Based on experimentally determined mean linear distances between grain boundaries as well as ab initio calculations of the electron mean free path, the data for Ru, Ir, and Cu were modeled within the semiclassical Mayadas--Shatzkes model [Phys. Rev. B 1, 1382 (1970)] to assess the combined contributions of surface and grain boundary scattering to the resistivity. For Ru, the modeling results indicated that surface scattering was strongly dependent on the surrounding material with nearly specular scattering at interfaces with SiO2 or air but with diffuse scattering at interfaces with TaN. The dependence of the thin film resistivity on the mean free path is also discussed within the Mayadas--Shatzkes model in consideration of the experimental findings.Comment: 28 pages, 9 figure

    Prospective and dyadic associations between expectant parentsā€™ prenatal hormone changes and postpartum parenting outcomes

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    During the transition to parenthood, both men and women experience hormone changes that are thought to promote parental care. Yet very few studies have explicitly tested the hypothesis that prenatal hormone changes are associated with postpartum parenting behavior. In a longitudinal study of 27 firstā€time expectant couples, we assessed whether prenatal hormone changes were moderated by selfā€ and partnerā€reported parenting outcomes at 3 months postpartum. Expectant fathers showed prenatal declines in testosterone and estradiol, and larger declines in these hormones were associated with greater contributions to household and infant care tasks postpartum. Women whose partners showed larger testosterone declines also reported receiving more support and more help with household tasks. Expectant mothers showed prenatal increases in testosterone and estradiol, and larger increases in these hormones were associated with lower partnerā€rated support. Together, our findings provide some of the first evidence that prenatal hormone changes may indeed be functional and that the implications of these changes may be detectable by coā€parents.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135629/1/dev21469_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135629/2/dev21469.pd

    Trends in community response and long term outcomes from paediatric cardiac arrest:A retrospective observational study

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    AIM: This study aimed to investigate trends over time in pre-hospital factors for pediatric out-of-hospital cardiac arrest (pOHCA) and long-term neurological and neuropsychological outcomes. These have not been described before in large populations.METHODS: Non-traumatic arrest patients, 1 day-17 years old, presented to the Sophia Children's Hospital from January 2002 to December 2020, were eligible for inclusion. Favorable neurological outcome was defined as Pediatric Cerebral Performance Categories (PCPC) 1-2 or no difference with pre-arrest baseline. The trend over time was tested with multivariable logistic and linear regression models with year of event as independent variable.FINDINGS: Over a nineteen-year study period, the annual rate of long-term favorable neurological outcome, assessed at a median 2Ā·5 years follow-up, increased significantly (OR 1Ā·10, 95%-CI 1Ā·03-1Ā·19), adjusted for confounders. Concurrently, annual automated external defibrillator (AED) use and, among adolescents, initial shockable rhythm increased significantly (OR 1Ā·21, 95% CI 1Ā·10-1Ā·33 and OR 1Ā·15, 95% CI 1Ā·02-1Ā·29, respectively), adjusted for confounders. For generalizability purposes, only the total intelligence quotient (IQ) was considered for trend analysis of all tested domains. Total IQ scores and bystander basic life support (BLS) rate did not change significantly over time.INTERPRETATION: Long-term favorable neurological outcome, assessed at a median 2Ā·5 years follow-up, improved significantly over the study period. Total IQ scores did not significantly change over time. Furthermore, AED use (OR 1Ā·21, 95%CI 1.10-1Ā·33) and shockable rhythms among adolescents (OR1Ā·15, 95%CI 1Ā·02-1Ā·29) increased over time.</p

    Internet Affairs: Partnersā€™ Perceptions and Experiences of Internet Infidelity

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    This study utilizes an online survey (open and closed questions) to examine how those whose partnersā€™ have engaged in online affairs define and experience online infidelity. As with offline affairs, respondents were most likely to define sexual (vs. emotional) behaviors as infidelity (e.g., cybersex, exchanging sexual self-images, sharing sexual fantasies online). However, thematic analysis of the qualitative data identified how online behaviors and spaces are confusing and that infidelity is defined more broadly and fluidly in the online context. This potentially explains why participants saw the Internet as facilitating affairs. Findings are discussed in relation to existing literature and study limitations

    Changing gender roles and attitudes and their implications for well-being around the new millennium

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    &lt;b&gt;Purpose&lt;/b&gt;&lt;p&gt;&lt;/p&gt; Given evidence that gender role attitudes (GRAs) and actual gender roles impact on well-being, we examine associations between GRAs, three roles (marital status, household chore division, couple employment) and psychological distress in working-age men and women. We investigate time-trends reflecting broader social and economic changes, by focusing on three age groups at two dates.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Methods&lt;/b&gt;&lt;p&gt;&lt;/p&gt; We used British Household Panel Survey data from 20- to 64-year-olds in heterosexual couple households in 1991 (N = 5,302) and 2007 (N = 6,621). We examined: levels of traditional GRAs according to gender, age, date, household and employment roles; associations which GRAs and roles had with psychological distress (measured via the GHQ-12); whether psychological distress increased when GRAs conflicted with actual roles; and whether any of these associations differed according to gender, age or date.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Results&lt;/b&gt;&lt;p&gt;&lt;/p&gt; Gender traditionalism was lower among women, younger people, those participating in 2007 and in ā€˜less traditionalā€™ relationships and households. Psychological distress was higher among those with more traditional GRAs and, particularly among men, for those not employed, and there was some evidence of different patterns of association according to age-group. There was limited evidence, among women only, of increased psychological distress when GRAs and actual roles conflicted and/or reductions when GRAs and roles agreed, particularly in respect of household chores and paid employment.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusions&lt;/b&gt;&lt;p&gt;&lt;/p&gt; Although some aspects of gender roles and attitudes (traditionalism and paid employment) are associated with well-being, others (marital status and household chores), and attitude-role consistency, may have little impact on the well-being of contemporary UK adults.&lt;p&gt;&lt;/p&gt
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