33 research outputs found
A Xenon Condenser with a Remote Liquid Storage Vessel
We describe the design and operation of a system for xenon liquefaction in
which the condenser is separated from the liquid storage vessel. The condenser
is cooled by a pulse tube cryocooler, while the vessel is cooled only by the
liquid xenon itself. This arrangement facilitates liquid particle detector
research by allowing easy access to the upper and lower flanges of the vessel.
We find that an external xenon gas pump is useful for increasing the rate at
which cooling power is delivered to the vessel, and we present measurements of
the power and efficiency of the apparatus.Comment: 22 pages, 7 figures Corrected typos in authors lis
Impact of germline and somatic missense variations on drug binding sites.
Advancements in next-generation sequencing (NGS) technologies are generating a vast amount of data. This exacerbates the current challenge of translating NGS data into actionable clinical interpretations. We have comprehensively combined germline and somatic nonsynonymous single-nucleotide variations (nsSNVs) that affect drug binding sites in order to investigate their prevalence. The integrated data thus generated in conjunction with exome or whole-genome sequencing can be used to identify patients who may not respond to a specific drug because of alterations in drug binding efficacy due to nsSNVs in the target protein\u27s gene. To identify the nsSNVs that may affect drug binding, protein-drug complex structures were retrieved from Protein Data Bank (PDB) followed by identification of amino acids in the protein-drug binding sites using an occluded surface method. Then, the germline and somatic mutations were mapped to these amino acids to identify which of these alter protein-drug binding sites. Using this method we identified 12 993 amino acid-drug binding sites across 253 unique proteins bound to 235 unique drugs. The integration of amino acid-drug binding sites data with both germline and somatic nsSNVs data sets revealed 3133 nsSNVs affecting amino acid-drug binding sites. In addition, a comprehensive drug target discovery was conducted based on protein structure similarity and conservation of amino acid-drug binding sites. Using this method, 81 paralogs were identified that could serve as alternative drug targets. In addition, non-human mammalian proteins bound to drugs were used to identify 142 homologs in humans that can potentially bind to drugs. In the current protein-drug pairs that contain somatic mutations within their binding site, we identified 85 proteins with significant differential gene expression changes associated with specific cancer types. Information on protein-drug binding predicted drug target proteins and prevalence of both somatic and germline nsSNVs that disrupt these binding sites can provide valuable knowledge for personalized medicine treatment. A web portal is available where nsSNVs from individual patient can be checked by scanning against DrugVar to determine whether any of the SNVs affect the binding of any drug in the database.The Pharmacogenomics Journal advance online publication, 26 January 2016; doi:10.1038/tpj.2015.97
The Q^2 evolution of the generalized Gerasimov-Drell-Hearn integral for the neutron using a He-3 target
We present data on the inclusive scattering of polarized electrons from a
polarized He-3 target at energies from 0.862 to 5.06 GeV, obtained at a
scattering angle of 15.5 degrees. Our data include measurements from the
quasielastic peak, through the resonance region, to the beginning of the deep
inelastic regime, and were used to determine the spin difference in the virtual
photoabsorption cross section. We extract the extended Gerasimov-Drell-Hearn
integral for the neutron in the range of 4-momentum transfer squared Q^2 of
0.1-0.9 GeV.Comment: 14 pages of text when TeXed in preprint format with figures embedded.
RevTeX format. Three eps figure
Measurement of the Generalized Forward Spin Polarizabilities of the Neutron
The generalized forward spin polarizabilities and of
the neutron have been extracted for the first time in a range from 0.1 to
0.9 GeV. Since is sensitive to nucleon resonances and
is insensitive to the resonance, it is expected that the
pair of forward spin polarizabilities should provide benchmark tests of the
current understanding of the chiral dynamics of QCD. The new results on
show significant disagreement with Chiral Perturbation Theory
calculations, while the data for at low are in good agreement
with a next-to-lead order Relativistic Baryon Chiral Perturbation theory
calculation. The data show good agreement with the phenomenological MAID model.Comment: 5 pages, 2 figures, corrected typo in author name, published in PR
Q^2 Evolution of the Neutron Spin Structure Moments using a He-3 Target
We have measured the spin structure functions and of He in a
double-spin experiment by inclusively scattering polarized electrons at
energies ranging from 0.862 to 5.07 GeV off a polarized He target at a
15.5 scattering angle. Excitation energies covered the resonance and
the onset of the deep inelastic regions. We have determined for the first time
the evolution of ,
and for the neutron in the range 0.1 GeV 0.9 GeV with good precision. displays a smooth
variation from high to low . The Burkhardt-Cottingham sum rule holds
within uncertainties and is non-zero over the measured range.Comment: 5 pages, 2 figures, submitted to Phys. Rev. Lett.. Updated Hermes
data in Fig. 2 (top panel) and their corresponding reference. Updated the low
x extrapolation error Fig. 2 (middle panel). Corrected references to ChiPT
calculation
A xenon gas purity monitor for EXO
We discuss the design, operation, and calibration of two versions of a xenon
gas purity monitor (GPM) developed for the EXO double beta decay program. The
devices are sensitive to concentrations of oxygen well below 1 ppb at an
ambient gas pressure of one atmosphere or more. The theory of operation of the
GPM is discussed along with the interactions of oxygen and other impurities
with the GPM's tungsten filament. Lab tests and experiences in commissioning
the EXO-200 double beta decay experiment are described. These devices can also
be used on other noble gases.Comment: 41 pages, 26 figure
^3He spin-dependent cross sections and sum rules
We present a measurement of the spin-dependent cross sections for the ^3He(e,e) X reaction in the quasielastic and resonance regions at a four-momentum transfer 0:1 ≤ Q^2 ≤ 0:9 GeV^2. The spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt-Cottingham and extended Gerasimov-Drell-Hearn sum rules for the first time. The data are also compared to an impulse approximation calculation and an exact three-body Faddeev calculation in the quasielastic region
Dynamics of the O(e,e'p) cross section at high missing energies
We measured the cross section and response functions (R_L, R_T, and R_LT) for the 16O(e,e'p) reaction in quasielastic kinematics for missing energies 25 60 MeV and P_miss > 200 MeV/c, the cross section is relatively constant. Calculations which include contributions from pion exchange currents, isobar currents and short-range correlations account for the shape and the transversity but only for half of the magnitude of the measured cross section
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Intercomparison of Landsat Operational Land Imager and Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer Radiometric Calibrations Using Radiometric Calibration Network Data
This paper presents a comprehensive intercomparison study investigating the radiometric performance of and concurrence among the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Landsat 8 Operational Land Imager (L8 OLI), and Landsat 9 OLI (L9 OLI) instruments. This study leverages data sourced from the Radiometric Calibration Network (RadCalNet) and focuses on spectral bands relevant for vegetation analysis and land cover classification, encompassing a thorough assessment of data quality, uncertainties, and underlying influencing factors. This study’s outcomes underscore the efficacy of RadCalNet in evaluating the precision and reliability of remote sensing data, offering valuable insights into the strengths and limitations of ASTER, L8 OLI, and L9 OLI. These insights serve as a foundation for informed decision making in environmental monitoring and resource management, highlighting the pivotal role of RadCalNet in gauging the radiometric performance of remote sensing sensors. Results from RadCalNet sites, namely Railroad Valley Playa and Gobabeb, show their possible suitability for sensors with spatial resolutions down to 15 m. The results indicate that the measurements from both ASTER and OLI closely align with the data from RadCalNet, and the observed agreement falls comfortably within the total range of potential errors associated with the sensors and the test site information. © 2024 by the authors.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]