198 research outputs found

    Metamorphic rocks in the Sawtooth Mountains, Idaho, USA: a window into the Precambrian basement of southwest Laurentia

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    The western North American craton consists of a mosaic of Precambrian basement terranes that developed through episodes of microcontinent collision and magmatic arc accretion. Defining the extent and boundaries of these terranes is critical to deciphering the Precambrian development of Laurentia. The poorly exposed Selway terrane occurs between the Archean Wyoming province and the Neoproterozoic rifted margin of Laurentia. A rare exposure of Precambrian metamorphic rocks, the Sawtooth Metamorphic Complex (SMC), crops out over 33 km2 in the Sawtooth Mountains of Idaho, USA, and potentially provides a window into the deep crust of the region. Field mapping, petrographic analyses, and mineral chemical data characterize the nature of the SMC rocks. Nine rock types occur in the SMC: quartzite, quartzofeldspathic gneiss, calc-silicate gneiss, marble mylonite, titanite-hornblende-biotite gneiss, metagabbro, biotite-amphibolite, peraluminous gneiss, and amphibole-pyroxene gneiss. Cross-cutting relationships and mineral-replacement textures in the Iron Creek peraluminous gneiss indicate the rocks passed through muscovite stability in the sillimanite field during prograde metamorphism, resulting in the reaction: muscovite + quartz sillimanite + K-feldspar + H2O. Fine-grained biotite and sillimanite are included in cordierite suggesting the reaction: phlogopite + sillimanite Mg-cordierite + garnet + H2O. These two dehydration reactions contribute to partial melting of the rocks and migmitization at peak metamorphic conditions interpreted at T = 800°C and P = 7 kbar. Tabular muscovite and euhedral andalusite cross-cut the main foliation in Iron Creek peraluminous gneisses, indicating a clock-wise decrease in pressure and temperature during retrograde metamorphism. Thompson Peak rocks share similar prograde, peak, and post-peak conditions, but different retrograde paths. Thompson Peak rocks contain pseudomorphs of kyanite-overprints indicating the rocks remained at relatively high-temperature during retrograde metamorphism. Calculated metamorphic conditions, T = 680 – 750 ±40 °C and P = 5 – 7 ± 0.5 kbar, indicate the rocks are transitional granulites to amphibolites from the mid-lower crust. Clock-wise P-T paths suggest the SMC was metamorphosed in a collisional tectonic setting. However, different retrograde conditions in the Thompson Peak and Iron Creek regions suggest the SMC is composed of multiple tectonic slices from the mid-lower crust

    The azido[\u3csup\u3e14\u3c/sup\u3eC]atrazine photoaffinity technique labels a 34-kDa protein in Scenedesmus which functions on the oxidizing side of photosystem II

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    We have used azido[14C]atrazine to photoaffinity label thylakoids from wild-type (WT) Scenedesmus and a mutant, LF-1, which is blocked on the oxidizing side of photosystem II (PS II). One protein is labeled in each case, at 34 kDa in the WT and 36 kDa in LF-1. Previous comparison of the WT with LF-1 had been used to assign a PS II donor side function to the 34-kDa protein. These results suggest that this photoaffinity technique does not label the herbicide-binding protein involved in electron transfer on the reducing side of PS II. © 1985

    The relationship of gross upper and lower limb motor competence to measures of health and fitness in adolescents aged 13–14 years

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    Introduction: Motor competence (MC) is an important factor in the development of health and fitness in adolescence. Aims: This cross-sectional study aims to explore the distribution of MC across 13-14 year old school students and the extent of the relationship of MC to measures of health and fitness across genders. Methods: A total of 718 participants were tested from three different schools in the UK, 311 girls, and 407 boys (aged 13-14 years), pairwise deletion for correlation variables reduced this to 555 (245 girls, 310 boys). Assessments consisted of, body mass index, aerobic capacity, anaerobic power, upper limb and lower limb MC. The distribution of MC and the strength of the relationships between MC and health/fitness measures were explored. Results: Girls performed lower for MC and health/fitness measures compared to boys. Both measures of MC showed a normal distribution and a significant linear relationship of MC to all health and fitness measures for boys, girls, and combined genders. A stronger relationship was reported for upper limb MC and aerobic capacity when compared to lower limb MC and aerobic capacity in boys (t= -2.21, df= 307, p = 0.03, 95%CI -0.253 -0.011). Conclusion: Normally distributed measures of upper and lower limb MC are linearly related to health and fitness measures in adolescents in a UK sample. Trial Registration: NCT0251733

    A Geologic Study to Determine the Potential to Create an Appalachian Storage Hub for Natural Gas Liquids

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    The Marcellus and Utica shale plays continue to lead the way in an ever-expanding shale revolution with average daily production, growing from about 3 billion cubic feet (BCF) in 2010 to more than 24 BCF today. Forecasts suggest that this could grow to as much as 40 BCF in the next 5 years. Fortunately, sweet spots in the Utica in eastern Ohio and in the Marcellus in northern West Virginia and southwestern Pennsylvania are areas of wet gas production, downdip from oil production and updip from dry gas. Production in these regions represents about 40 percent of the total from the Marcellus and Utica shales and is expected to represent a disproportionate share of future production growth. Because of the amount of natural gas liquids (NGLs) contained in this production, development of these shale plays has the potential to have a large impact on the petrochemical industry

    MPLEx: a Robust and Universal Protocol for Single-Sample Integrative Proteomic, Metabolomic, and Lipidomic Analyses

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    ABSTRACT Integrative multi-omics analyses can empower more effective investigation and complete understanding of complex biological systems. Despite recent advances in a range of omics analyses, multi-omic measurements of the same sample are still challenging and current methods have not been well evaluated in terms of reproducibility and broad applicability. Here we adapted a solvent-based method, widely applied for extracting lipids and metabolites, to add proteomics to mass spectrometry-based multi-omics measurements. The m etabolite, p rotein, and l ipid ex traction (MPLEx) protocol proved to be robust and applicable to a diverse set of sample types, including cell cultures, microbial communities, and tissues. To illustrate the utility of this protocol, an integrative multi-omics analysis was performed using a lung epithelial cell line infected with Middle East respiratory syndrome coronavirus, which showed the impact of this virus on the host glycolytic pathway and also suggested a role for lipids during infection. The MPLEx method is a simple, fast, and robust protocol that can be applied for integrative multi-omic measurements from diverse sample types (e.g., environmental, in vitro , and clinical). IMPORTANCE In systems biology studies, the integration of multiple omics measurements (i.e., genomics, transcriptomics, proteomics, metabolomics, and lipidomics) has been shown to provide a more complete and informative view of biological pathways. Thus, the prospect of extracting different types of molecules (e.g., DNAs, RNAs, proteins, and metabolites) and performing multiple omics measurements on single samples is very attractive, but such studies are challenging due to the fact that the extraction conditions differ according to the molecule type. Here, we adapted an organic solvent-based extraction method that demonstrated broad applicability and robustness, which enabled comprehensive proteomics, metabolomics, and lipidomics analyses from the same sample

    The relationship of gross upper and lower limb motor competence to measures of health and fitness in adolescents aged 13-14 years

    Get PDF
    Introduction: Motor competence (MC) is an important factor in the development of health and fitness in adolescence. Aims: This cross-sectional study aims to explore the distribution of MC across 13-14 year old school students and the extent of the relationship of MC to measures of health and fitness across genders. Methods: A total of 718 participants were tested from three different schools in the UK, 311 girls, and 407 boys (aged 13-14 years), pairwise deletion for correlation variables reduced this to 555 (245 girls, 310 boys). Assessments consisted of, body mass index, aerobic capacity, anaerobic power, upper limb and lower limb MC. The distribution of MC and the strength of the relationships between MC and health/fitness measures were explored. Results: Girls performed lower for MC and health/fitness measures compared to boys. Both measures of MC showed a normal distribution and a significant linear relationship of MC to all health and fitness measures for boys, girls, and combined genders. A stronger relationship was reported for upper limb MC and aerobic capacity when compared to lower limb MC and aerobic capacity in boys (t= -2.21, df= 307, p = 0.03, 95%CI -0.253 -0.011). Conclusion: Normally distributed measures of upper and lower limb MC are linearly related to health and fitness measures in adolescents in a UK sample. Trial Registration: NCT0251733

    Measurement of the Proton Spin Structure Function g1p with a Pure Hydrogen Target

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    A measurement of the proton spin structure function g1p(x,Q^2) in deep-inelastic scattering is presented. The data were taken with the 27.6 GeV longitudinally polarised positron beam at HERA incident on a longitudinally polarised pure hydrogen gas target internal to the storage ring. The kinematic range is 0.021<x<0.85 and 0.8 GeV^2<Q^2<20 GeV^2. The integral Int_{0.021}^{0.85} g1p(x)dx evaluated at Q0^2 of 2.5 GeV^2 is 0.122+/-0.003(stat.)+/-0.010(syst.).Comment: 7 pages, 3 figures, 1 table, RevTeX late
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