1,006 research outputs found

    The effect of soil properties on zinc lability and solubility in soils of Ethiopia - an isotopic dilution study

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    Zinc (Zn) deficiency is a widespread nutritional problem in human populations, especially in sub-Saharan Africa (SSA). The Zn concentration of crops consumed depends in part on the Zn status of the soil. Improved understanding of factors controlling the phyto-availability of Zn in soils can contribute to potential agronomic interventions to tackle Zn deficiency, but many soil types in SSA are poorly studied. Soil samples (nCombining double low line475) were collected from a large part of the Amhara Region of Ethiopia, where there is widespread Zn deficiency. Zinc status was quantified by measuring several fractions, including the pseudo-total (aqua regia digestion; ZnTot), available (DTPA (diethylenetriamine pentaacetate) extractable; ZnDTPA), soluble (dissolved in 0.01MCa(NO3); ZnSoln) and isotopically exchangeable Zn, using the enriched stable Zn isotope 70Zn (ZnE). Soil geochemical properties were assessed for their influence on Zn lability and solubility. A parameterized geochemical assemblage model (Windermere Humic Aqueous Model - WHAM) was also employed to predict the solid phase fractionation of Zn in tropical soils rather than using sequential chemical extractions. ZnTot ranged from 14.1 to 291mgkg-1 (medianCombining double low line100mgkg-1), whereas ZnDTPA in the majority of soil samples was less than 0.5mgkg-1, indicating widespread phyto-available Zn deficiency in these soils. The labile fraction of Zn in soil (ZnE as %ZnTot) was low, with median and mean values of 4.7% and 8.0%, respectively. Labile Zn partitioning between the solid and the solution phases of soil was highly pH dependent, where 94% of the variation in the partitioning coefficient of 70Zn was explained by soil pH. Similarly, 86% of the variation in ZnSoln was explained by soil pH. Zinc distribution between adsorbed ZnE and ZnSoln was controlled by pH. Notably, Zn isotopic exchangeability increased with soil pH. This contrasts with literature on contaminated and urban soils and may arise from covarying factors, such as contrasting soil clay mineralogy across the pH range of the soils used in the current study. These results could be used to improve agronomic interventions to tackle Zn deficiency in SSA

    Androgen-regulated transcription of ESRP2 drives alternative splicing patterns in prostate cancer

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    Prostate is the most frequent cancer in men. Prostate cancer progression is driven by androgen steroid hormones, and delayed by androgen deprivation therapy (ADT). Androgens control transcription by stimulating androgen receptor (AR) activity, yet also control pre-mRNA splicing through less clear mechanisms. Here we find androgens regulate splicing through AR-mediated transcriptional control of the epithelial-specific splicing regulator ESRP2. Both ESRP2 and its close paralog ESRP1 are highly expressed in primary prostate cancer. Androgen stimulation induces splicing switches in many endogenous ESRP2-controlled mRNA isoforms, including splicing switches correlating with disease progression. ESRP2 expression in clinical prostate cancer is repressed by ADT, which may thus inadvertently dampen epithelial splice programmes. Supporting this, treatment with the AR antagonist bicalutamide (Casodex) induced mesenchymal splicing patterns of genes including FLNB and CTNND1. Our data reveals a new mechanism of splicing control in prostate cancer with important implications for disease progression.This article is freely available via Open Access. Click on the Publisher URL to access the full-text via the publisher's site

    The association between delusional-like experiences, and tobacco, alcohol or cannabis use: a nationwide population-based survey

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    <p>Abstract</p> <p>Background</p> <p>Previous population-based studies have found that delusional-like experiences (DLE) are prevalent in the community, and are associated with a wide range of mental health disorders including substance use. The aim of the study was to explore the association between DLE and three commonly used substances - tobacco, alcohol and cannabis.</p> <p>Methods</p> <p>Subjects were drawn from the Australian National Survey of Mental Health and Wellbeing 2007. The Composite International Diagnostic Interview was used to identify DLE, common psychiatric disorders, and substance use. We examined the relationship between the variables of interest using logistic regression, adjusting for potential confounding factors.</p> <p>Results</p> <p>Of 8 773 participants, 8.4% (n = 776) subjects endorsed one or more DLE. With respect to tobacco use, compared to nonusers, DLE were more common in those who (a) had daily use, (b) commenced usage aged 15 years or less, and (c) those who smoked heavily (23 or more cigarettes per day). Participants with cannabis use disorders were more likely to endorse DLE; this association was most prominent in those with an onset of 16 years or younger. In contrast, the pattern of association between DLE versus alcohol use or dependence was less consistent, however those with early onset alcohol use disorders were more likely to endorse DLE probe items.</p> <p>Conclusions</p> <p>While cannabis use disorders have been previously linked with DLE, our findings linking alcohol and tobacco use and DLE suggest that the influence of these substances on psychosis-related outcomes warrants closer scrutiny in longitudinal prospective studies.</p

    A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)

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    We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data sample consists of 29.7 fb1{\rm fb}^{-1} recorded at the Υ(4S)\Upsilon(4S) resonance and 3.9 fb1{\rm fb}^{-1} off-resonance. One of the neutral B mesons, which are produced in pairs at the Υ(4S)\Upsilon(4S), is fully reconstructed in the CP decay modes J/ψKS0J/\psi K^0_S, ψ(2S)KS0\psi(2S) K^0_S, χc1KS0\chi_{c1} K^0_S, J/ψK0J/\psi K^{*0} (K0KS0π0K^{*0}\to K^0_S\pi^0) and J/ψKL0J/\psi K^0_L, or in flavor-eigenstate modes involving D()π/ρ/a1D^{(*)}\pi/\rho/a_1 and J/ψK0J/\psi K^{*0} (K0K+πK^{*0}\to K^+\pi^-). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. A maximum-likelihood fit to this flavor eigenstate sample finds Δmd=0.516±0.016(stat)±0.010(syst)ps1\Delta m_d = 0.516\pm 0.016 {\rm (stat)} \pm 0.010 {\rm (syst)} {\rm ps}^{-1}. The value of the asymmetry amplitude sin2β\sin2\beta is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged B0B^0 decays in the CP-eigenstate modes. We find sin2β=0.59±0.14(stat)±0.05(syst)\sin2\beta=0.59\pm 0.14 {\rm (stat)} \pm 0.05 {\rm (syst)}, demonstrating that CP violation exists in the neutral B meson system. (abridged)Comment: 58 pages, 35 figures, submitted to Physical Review

    Promoting communication skills for information systems students in Australian and Portuguese higher education : action research study

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    This paper aims to examine the value of communication skills learn- ing process through various assessments in Information Systems (IS) postgrad- uate units in Australia and Portugal. Currently, communication skills are indispensable to students in expanding their social networks and their knowl- edge at university and in the future workplace, since businesses expect their employees to have strong communication and presentation skills. This paper provides empirical evidence based on the anonymous quantitative and qualita- tive data collected during 2 years from 126 postgraduate students, which were collected via formal and informal feedback. Various assessment methods were used in Information Systems units to promote and develop the communication skills; these assessments are: reflective journal, business plan and prototype, discussion forum, presentation, and final examination. A Communication skills model (CSM) was developed based on Action research principles to promote the assessments which will assist IS students to enhance their communication skills. The research outcomes indicated that integrating communication skills in the assessments will allow students to promote their communication skills and boost their self-esteem skills. Furthermore, this paper added a new theoretical and practical contribution to higher-education teaching and learning literature, especially the action research for teachers to promote and develop communica- tion skills among students. Finally, integrating these skills in the units should meet the objectives and aims of the units, Master’s degrees, universities, and businesses’ needs, and satisfy our student’s need

    Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events

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    The B0B^0-Bˉ0\bar B^0 oscillation frequency has been measured with a sample of 23 million \B\bar B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we select events in which both B mesons decay semileptonically and use the charge of the leptons to identify the flavor of each B meson. A simultaneous fit to the decay time difference distributions for opposite- and same-sign dilepton events gives Δmd=0.493±0.012(stat)±0.009(syst)\Delta m_d = 0.493 \pm 0.012{(stat)}\pm 0.009{(syst)} ps1^{-1}.Comment: 7 pages, 1 figure, submitted to Physical Review Letter

    Equal opportunities: Do shareable interfaces promote more group participation than single users displays?

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    Computers designed for single use are often appropriated suboptimally when used by small colocated groups working together. Our research investigates whether shareable interfaces–that are designed for more than one user to inter-act with–can facilitate more equitable participation in colocated group settings compared with single user displays. We present a conceptual framework that characterizes Shared Information Spaces (SISs) in terms of how they constrain and invite participation using different entry points. An experiment was conducted that compared three different SISs: a physical-digital set-up (least constrained), a multitouch tabletop (medium), and a laptop display (most constrained). Statistical analyses showed there to be little difference in participation levels between the three conditions other than a predictable lack of equity of control over the interface in the laptop condition. However, detailed qualitative analyses revealed more equitable participation took place in the physical-digital condition in terms of verbal utterances over time. Those who spoke the least contributed most to the physical design task. The findings are discussed in relation to the conceptual framework and, more generally, in terms of how to select, design, and combine different display technologies to support collaborative activities
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