1,338 research outputs found

    Evaluation of a Vivo-Morpholino Delivery Method to the Brain and the Affect on Physical Activity

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    Evaluation of a Vivo-Morpholino Delivery Method to the Brain and the Affect on Physical Activity *David P. Ferguson MS, Emily E. Schmitt MS, J. Timothy Lightfoot PhD FACSM Biology of Physical Activity Lab, Texas A&M University, College Station, TX, 77843 *To be judged in the doctoral category Physical inactivity has been shown to be correlated to various disease and conditions. Therefore, there is interest in the genetic mechanisms that control daily physical activity. Vivo-morpholinos are a new molecular biology tool that allows for the transient silencing of specific genes in an animal model, thereby allowing for a systematic method to turn off potential candidate genes involved in the regulation of physical activity. Vivo-morpholinos have not been shown to be effective at silencing genes in the brain due to the fact that the vivo-morpholino cannot cross the blood brain barrier. To counteract this, a tail vein injection (55 ul total volume; 11mg/kg vivo-morpholino; 6.5ug/kg RMP7) was given on three consecutive days containing the bradykinin analog RMP7 and a vivo-morpholino targeting Vmat2 to male C57/LJ mice (n=6). RMP7 has been shown to increase blood brain barrier permeability while Vmat2 is a dopamine transporter and is thought to be involved in the regulation of voluntary physical activity. Control animals received either RMP7 plus saline (n=6) or RMP7 plus a vivo-morpholino “scramble” control (n=6). Physical activity was measured by wheel running. Results showed there was not a significant (p=0.24) knockdown in Vmat2 in the brain with RMP7 administration as compared to control animals. Interestingly there was a significant (p=0.001) knockdown in daily physical activity in the Vmat2 treated animals compared to the control group. RMP7 may still be a viable option for vivo-morpholino delivery in the brain; however an increased dosage may be required

    Co-Variation between Seed Dormancy, Growth Rate and Flowering Time Changes with Latitude in Arabidopsis thaliana

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    Life-history traits controlling the duration and timing of developmental phases in the life cycle jointly determine fitness. Therefore, life-history traits studied in isolation provide an incomplete view on the relevance of life-cycle variation for adaptation. In this study, we examine genetic variation in traits covering the major life history events of the annual species Arabidopsis thaliana: seed dormancy, vegetative growth rate and flowering time. In a sample of 112 genotypes collected throughout the European range of the species, both seed dormancy and flowering time follow a latitudinal gradient independent of the major population structure gradient. This finding confirms previous studies reporting the adaptive evolution of these two traits. Here, however, we further analyze patterns of co-variation among traits. We observe that co-variation between primary dormancy, vegetative growth rate and flowering time also follows a latitudinal cline. At higher latitudes, vegetative growth rate is positively correlated with primary dormancy and negatively with flowering time. In the South, this trend disappears. Patterns of trait co-variation change, presumably because major environmental gradients shift with latitude. This pattern appears unrelated to population structure, suggesting that changes in the coordinated evolution of major life history traits is adaptive. Our data suggest that A. thaliana provides a good model for the evolution of trade-offs and their genetic basis.<br

    The Atacama Cosmology Telescope: Two-Season ACTPol Spectra and Parameters

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    We present the temperature and polarization angular power spectra measured by the Atacama Cosmology Telescope Polarimeter (ACTPol). We analyze night-time data collected during 2013-14 using two detector arrays at 149 GHz, from 548 deg2^2 of sky on the celestial equator. We use these spectra, and the spectra measured with the MBAC camera on ACT from 2008-10, in combination with Planck and WMAP data to estimate cosmological parameters from the temperature, polarization, and temperature-polarization cross-correlations. We find the new ACTPol data to be consistent with the LCDM model. The ACTPol temperature-polarization cross-spectrum now provides stronger constraints on multiple parameters than the ACTPol temperature spectrum, including the baryon density, the acoustic peak angular scale, and the derived Hubble constant. Adding the new data to planck temperature data tightens the limits on damping tail parameters, for example reducing the joint uncertainty on the number of neutrino species and the primordial helium fraction by 20%.Comment: 23 pages, 25 figure

    The atacama cosmology telescope: lensing of CMB temperature and polarization derived from cosmic infrared background cross-correlation

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    We present a measurement of the gravitational lensing of the Cosmic Microwave Background (CMB) temperature and polarization fields obtained by cross-correlating the reconstructed convergence signal from the first season of Atacama Cosmology Telescope Polarimeter data at 146 GHz with Cosmic Infrared Background (CIB) fluctuations measured using the Planck satellite. Using an effective overlap area of 92.7 square degrees, we detect gravitational lensing of the CMB polarization by large-scale structure at a statistical significance of 4.5σ4.5\sigma . Combining both CMB temperature and polarization data gives a lensing detection at 9.1σ9.1\sigma significance. A B-mode polarization lensing signal is present with a significance of 3.2σ3.2\sigma . We also present the first measurement of CMB lensing–CIB correlation at small scales corresponding to l>2000l\gt 2000. Null tests and systematic checks show that our results are not significantly biased by astrophysical or instrumental systematic effects, including Galactic dust. Fitting our measurements to the best-fit lensing-CIB cross-power spectrum measured in Planck data, scaled by an amplitude A, gives A=1.020.08+0.12A={1.02}_{-0.08}^{+0.12}(stat.) ± 0.06(syst.), consistent with the Planck results

    The Sariçiçek Howardite Fall in Turkey: Source Crater of HED Meteorites on Vesta and İmpact Risk of Vestoids

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    The Sariçiçek howardite meteorite shower consisting of 343 documented stones occurred on 2 September 2015 in Turkey and is the first documented howardite fall. Cosmogenic isotopes show that Sariçiçek experienced a complex cosmic ray exposure history, exposed during ~12–14 Ma in a regolith near the surface of a parent asteroid, and that an ~1 m sized meteoroid was launched by an impact 22 ± 2 Ma ago to Earth (as did one third of all HED meteorites). SIMS dating of zircon and baddeleyite yielded 4550.4 ± 2.5 Ma and 4553 ± 8.8 Ma crystallization ages for the basaltic magma clasts. The apatite U-Pb age of 4525 ± 17 Ma, K-Ar age of ~3.9 Ga, and the U,Th-He ages of 1.8 ± 0.7 and 2.6 ± 0.3 Ga are interpreted to represent thermal metamorphic and impact-related resetting ages, respectively. Petrographic, geochemical and O-, Cr- and Tiisotopic studies confirm that Sariçiçek belongs to the normal clan of HED meteorites. Petrographic observations and analysis of organic material indicate a small portion of carbonaceous chondrite material in the Sariçiçek regolith and organic contamination of the meteorite after a few days on soil. Video observations of the fall show an atmospheric entry at 17.3 ± 0.8 kms-1 from NW, fragmentations at 37, 33, 31 and 27 km altitude, and provide a pre-atmospheric orbit that is the first dynamical link between the normal HED meteorite clan and the inner Main Belt. Spectral data indicate the similarity of Sariçiçek with the Vesta asteroid family (V-class) spectra, a group of asteroids stretching to delivery resonances, which includes (4) Vesta. Dynamical modeling of meteoroid delivery to Earth shows that the complete disruption of a ~1 km sized Vesta family asteroid or a ~10 km sized impact crater on Vesta is required to provide sufficient meteoroids ≤4 m in size to account for the influx of meteorites from this HED clan. The 16.7 km diameter Antonia impact crater on Vesta was formed on terrain of the same age as given by the 4He retention age of Sariçiçek. Lunar scaling for crater production to crater counts of its ejecta blanket show it was formed ~22 Ma ago
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