2,082 research outputs found
The folic acid metabolism gene mel-32/Shmt is required for normal cell cycle lengths in Caenorhabditis elegans
Neural tube defects are common and serious birth defects in which the brain and/or spinal cord are exposed outside the body. Supplementation of foods with folic acid, an essential vitamin, is linked to a lower risk of neural tube defects; however, the mechanisms by which folic acid influence neural tube defect risk are unclear. Our research seeks to identify the basic cellular roles of known folic acid metabolism genes during morphogenesis using the roundworm Caenorhabditis elegans (C. elegans) as a simple model system. Here, we used live imaging to characterize defects in embryonic development when mel-32 is depleted. mel-32 is an essential folic acid metabolism gene in C. elegans and a homolog to the mammalian enzyme serine hydroxymethyltransferase (Shmt). Disruption of mel-32 resulted in a doubling or tripling of cell cycle lengths and a lack of directed cell movement during embryogenesis. However, the order of cell divisions, as determined by lineage analysis, is unchanged compared to wild type embryos. These results suggest that mel32/Shmt is required for normal cell cycle lengths in C. elegans
Do children\u27s food preferences align with dietary recommendations?
Objectives: To examine how Australian children\u27s reported everyday food preferences reflect dietary recommendations, and the impact of sociodemographic factors on these associations.Design: Cross-sectional survey.Setting/subjects: Three hundred and seventy-one parents of children aged 2–5 years, recruited from three socio-economic groups in two Australian cities, completed a survey on their child\u27s liking for 176 foods and drinks on a 5-point Likert scale in addition to demographic descriptors. Preferences were compared with the recommendations of the Dietary Guidelines for Children and Adolescents in Australia and the Australian Guide to Healthy Eating.Results: Foods in the Extra Foods (non-nutritious foods) and Cereals groups of the Australian Guide to Healthy Eating were highly liked (mean: 4.02 and 4.01, respectively), whilst foods in the Vegetables group were liked least (mean: 3.01). A large percentage of foods in the Cereals and Extra Foods groups were liked (64% and 56%, respectively) in contrast to the other food groups, especially Vegetables (7%). Children liked foods that were higher in sugar (r = 0.29, P < 0.0001) and more energy-dense (r = 0.34, P < 0.0001) but not those higher in saturated fat (r = 0.16, P = 0.03), total fat (r = 0.12, P = 0.12) or sodium (r = 0.10, P = 0.18). Sociodemographic variables (e.g. socio-economic status, parental education, children\u27s age and sex) explained little of the variation in children\u27s food preferences.Conclusions: Australian pre-school children\u27s food preferences align with dietary guidelines in some respects, but not others. Interventions are needed to shift children\u27s preferences away from non-nutritious foods that are high in energy density and sugar, and towards vegetables and fruits.<br /
Decreased NADPH oxidase expression and antioxidant activity in cachectic skeletal muscle
Background - Cancer cachexia is the progressive loss of skeletal muscle protein that contributes significantly to cancer morbidity and mortality. Evidence of antioxidant attenuation and the presence of oxidised proteins in patients with cancer cachexia indicate a role for oxidative stress. The level of oxidative stress in tissues is determined by an imbalance between reactive oxygen species production and antioxidant activity. This study aimed to investigate the superoxide generating NADPH oxidase (NOX) enzyme and antioxidant enzyme systems in murine adenocarcinoma tumour-bearing cachectic mice. Methods - Superoxide levels, mRNA levels of NOX enzyme subunits and the antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidise (GPx) and catalase was measured in the skeletal muscle of mice with cancer and cancer cachexia. Protein expression levels of NOX enzyme subunits and antioxidant enzyme activity was also measured in the same muscle samples. Results - Superoxide levels increased 1.4-fold in the muscle of mice with cancer cachexia, and this was associated with a decrease in mRNA of NOX enzyme subunits, NOX2, p40phox and p67phox along with the antioxidant enzymes SOD1, SOD2 and GPx. Cancer cachexia was also associated with a 1.3-fold decrease in SOD1 and 2.0-fold decrease in GPx enzyme activity. Conclusion - Despite increased superoxide levels in cachectic skeletal muscle, NOX enzyme subunits, NOX2, p40phox and p67phox, were downregulated along with the expression and activity of the antioxidant enzymes. Therefore, the increased superoxide levels in cachectic skeletal muscle may be attributed to the reduction in the activity of endogenous antioxidant enzymes
A simple scheme for allocating capital in a foreign exchange proprietary trading firm
We present a model of capital allocation in a foreign exchange proprietary trading firm. The owner allocates capital to individual traders, who operate within strict risk limits. Traders specialize in individual currencies, but are given discretion over their choice of trading rule. The owner provides the simple formula that determines position sizes – a formula that does not require estimation of the firm-level covariance matrix. We provide supporting empirical evidence of excess risk-adjusted returns to the firm-level portfolio, and we discuss a modification of the model in which the owner dictates the choice of trading rule
Multiple Parton Interactions in Z+jets production at the LHC. A comparison of factorized and non--factorized double parton distribution functions
We examine the contribution of Multiple Parton Interactions to Z+n-jets
production at the LHC, n=2,3,4, where the Z boson is assumed to decay
leptonically. We compare the results obtained with the correlated GS09 double
parton distribution function with those obtained with two instances of fully
factorized single parton distribution functions: MSTW2008LO and CTEQ6LO. It
appears quite feasible to measure the MPI contribution to Z+2/3/4 jets already
in the first phase of the LHC with a total luminosity of one inverse femtobarn
at 7 TeV. If as expected the trigger threshold for single photons is around 80
GeV, Z+2-jets production may well turn out to be more easily observable than
the gamma+3-jets channel. The MPI cross section is dominated by relatively soft
events with two jets balancing in transverse momentum.Comment: 15 pages, 3 plot
Elastic electron scattering from 3-hydroxytetrahydrofuran: experimental and theoretical studies
We report the results of measurements and calculations for elastic electron scattering from 3-hydroxytetrahydrofuran (C4H8O2). The measurements are performed with a crossed electron-target beam apparatus and the absolute cross-sections are determined using the relative flow technique. The calculations are carried out using the Schwinger multichannel method in the static-exchange plus polarization (SEP) approximation. A set of angular differential cross-sections (DCS) is provided at five incident energies (6.5, 8, 10, 15 and 20 eV) over an angular range of 20–130°, and the energy dependence of the elastic DCS at a scattering angle of 120° is also presented. Integral elastic and elastic momentum transfer cross-sections have also been derived and calculated. The results are compared with those of recent measurements and calculations for the structurally similar molecule tetrahydrofuran (C4H8O)
Effectiveness of enhanced diabetes care to patients of South Asian ethnicity : the United Kingdom Asian Diabetes Study (UKADS) : a cluster randomised controlled trial
Background: Delivering high quality and evidence based healthcare to deprived sectors of the community is a major goal for society. We investigated the effectiveness of a culturally sensitive enhanced care package in UK general practice in improving cardiovascular risk factors in South Asian patients with type 2 diabetes.
Methods: 21 inner city practices were randomised to intervention (enhanced practice nurse time, link worker and diabetes specialist nurse support) (n=868) or control (standard care) (n=618) groups. Prescribing algorithms with clearly defined targets were provided for all practices. Main outcome measures comprised changes in blood pressure, total cholesterol and glycaemic control (HbA1c) after 2 years.
Findings: At baseline, groups were similar with respect to age, sex and cardiovascular risk factors.
Comparing treatment groups, after adjustment for confounders, and clustering, differences in diastolic blood pressure (1.91mmHg, P=0.0001) and mean arterial pressure (1.36mmHg, P=0.0180) were significant. There were no significant differences between groups for total cholesterol or HbA1c. Economic analysis indicates the nurse-led intervention was not cost-effective.
Across the whole study population systolic blood pressure, diastolic blood pressure and cholesterol decreased significantly by 4.9mmHg, 3.8mmHg and 0.45mmol/L respectively, but there was no change in HbA1c.
Interpretation: Additional, although limited, benefits were observed from our culturally enhanced care package over and above the secular changes achieved in the UK in recent years. Stricter targets in general practice and further measures to motivate patients are needed to maximise healthcare outcomes in South Asian patients with diabetes
Standard SANC modules for NLO QCD Radiative Corrections to Single-top Production
It this paper we present the results obtained with the newly created Standard
SANC modules for calculation of the NLO QCD corrections to single top
production processes in s and t channels at the partonic level, as well as
top-decays. The main aim of these results is to prove the correct work of
modules. A comprehensive comparison with results of the CompHEP system is
given, where possible. These modules are intended to be used in Monte Carlo
generators for single top production processes at the LHC. As in our recent
paper, devoted to the electroweak corrections to these processes, we study the
regularization of the top-legs associated infrared divergences with aid of the
complex mass of the top quark. A comparison of QCD corrections with those
computed by the conventional method is presented both for top production and
decays. For s channel production we give an analytic proof of equivalence of
the two methods in the limit of low top width.Comment: 21 pages, 2 figures, 17 table
CE13009
Use the URI link below to search the Marine Institute Data Discovery Catalogue for datasets relevant to this report.The northwest and west coast (ICES Divisions VIaS & VIIb, c) herring acoustic survey
programme was first established in 1994.The summer 2013 survey represents the sixth in the new time series (est. in 2008). The
survey was coordinated through the ICES Working Group of International Pelagic Surveys (WGIPS). The Irish component was carried out to cover the statistical rectangles between 53°30’-58°30' N and 12°-5° W as laid out in the WGI PS report (ICES, 2012). Combined survey data on herring distribution, abundance and age are used to provide a measure of the relative abundance of herring within the Malin shelf stock complex. Survey data on stock numbers at age are submitted to the ICES Herring Assessment Working Group (HAWG) and used in the annual stock assessment process.The northwest and west coast (ICES Divisions VIaS & VIIb) herring stock is composed of two
spawning components, autumn and winter spawners. Spawning covers a large geographical area and extends over a 4-month period from late September through to late March (Molloy et al, 2000). Traditionally, fishing effort has been concentrated on spawning and pre-spawning aggregations. The autumn spawning component, which mostly occurs within VIIb and VIaS, feeds along the shelf break area to the west of the spawning grounds. The larger winter spawning component is found further north in VIa. In VIaS, summer distribution extends from
close inshore to the shelf break. Components of the winter spawning fish are known to
undertake northward feeding migration into VIaN before returning in the winter to spawn along the Irish coast
Is Vtb=1 ?
The strongest constraint on Vtb presently comes from the 3 x 3 unitarity of
the CKM matrix, which fixes Vtb to be very close to one. If the unitarity is
relaxed, current information from top production at Tevatron still leaves open
the possibility that Vtb is sizably smaller than one. In minimal extensions of
the standard model with extra heavy quarks, the unitarity constraints are much
weaker and the EW precision parameters entail the strongest bounds on Vtb. We
discuss the experimental perspectives of discovering and identifying such new
physics models at the Tevatron and the LHC, through a precise measurement of
Vtb from the single top cross sections and by the study of processes where the
extra heavy quarks are produced.Comment: 19 pages, 8 figure
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