20,163 research outputs found
THE EFFECT OF AN EMBARGO OF CALIFORNIA PEACHES
International Relations/Trade,
Atomic data for S II - Toward Better Diagnostics of Chemical Evolution in High-redshift Galaxies
Absorption-line spectroscopy is a powerful tool used to estimate element
abundances in the nearby as well as distant universe. The accuracy of the
abundances thus derived is, naturally, limited by the accuracy of the atomic
data assumed for the spectral lines. We have recently started a project to
perform the new extensive atomic data calculations used for optical/UV spectral
lines in the plasma modeling code Cloudy using state-of-the-art quantal
calculations. Here we demonstrate our approach by focussing on S II, an ion
used to estimate metallicities for Milky Way interstellar clouds as well as
distant damped Lyman-alpha (DLA) and sub-DLA absorber galaxies detected in the
spectra of quasars and gamma-ray bursts (GRBs). We report new extensive
calculations of a large number of energy levels of S II, and the line strengths
of the resulting radiative transitions. Our calculations are based on the
configuration interaction approach within a numerical Hartree-Fock framework,
and utilize both non-ralativistic and quasirelativistic one-electron radial
orbitals. The results of these new atomic calculations are then incorporated
into Cloudy and applied to a lab plasma, and a typical DLA, for illustrative
purposes. The new results imply relatively modest changes (~0.04 dex) to the
metallicities estimated from S II in past studies. These results will be
readily applicable to other studies of S II in the Milky Way and other
galaxies.Comment: Accepted for publication in The Astrophysical Journal; 34 pages, 10
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Hairy Leukoplakia
Oral hairy leukoplakia (OHL) is a disease of the mucosa first described in 1984. This pathology is associated with Epstein-Barr virus (EBV) and occurs mostly in people with HIV infection, both immunocompromised and immunocompetent, and can affect patients who are HIV negative. [1, 2] The first case in an HIV-negative patient was reported in 1999 in a 56-year-old patient with acute lymphocytic leukemia. Later, many cases were reported in heart, kidney, and bone marrow transplant recipients and patients with hematological malignancies. [3, 4
Rapid detection and quantification of features such as damage or flaws in composite and metallic structures
An apparatus, system, and method for non-destructible evaluation (NDE) of a material use thermography to rapidly detect and/or generally locate a feature such as, for example, damage or a defect in the material. The apparatus, system, and method also use ultrasound to specifically locate the feature in the material for quantification and/or evaluation either by an operator or by an external device suited for such purpose. Accordingly, the apparatus, system and method are particularly useful for NDE in applications such as the analysis of the structure of an aircraft, for example, in which the scale of the material to be analyzed is large, thus requiring the rapid NDE afforded by thermography, and in which quantification and/or evaluation of a feature must be performed with precision, thus requiring the relatively high-resolution NDE afforded by ultrasound
Atypical presentation of neuronal ceroid lipofuscinosis type 8 in a sibling pair and review of the eye findings and neurological features.
Purpose:To report atypical presentation of neuronal ceroid lipofuscinoses type 8 (CLN8) to the eye clinic and review clinical features of CLN8. Observations:Detailed eye exam by slit lamp exam, indirect ophthalmoscopy, fundus photography, optical coherence tomography, visual fields and electroretinogram (ERG). Molecular genetic testing using Next Generation Sequencing panel (NGS) and array Comparative Genomic Hybridization (aCGH).The siblings in this study presented to the eye clinic with retinitis pigmentosa and cystoid macular edema, and a history of seizures but no severe neurocognitive deficits or regression. Genetic testing identified a c.200CÂ >Â T (p.A67V) variant in the CLN8 gene and a deletion encompassing the entire gene. Electron microscopy of lymphocytes revealed fingerprint inclusions in both siblings. Conclusions:and Importance: Pathogenic variants in CLN8 account for the retinitis pigmentosa and seizures in our patients however, currently, they do not have regression or neurocognitive decline. The presentation of NCL can be very diverse and it is important for ophthalmologists to consider this in the differential diagnosis of retinal disorders with seizures or other neurological features. Molecular genetic testing of multiple genes causing isolated and syndromic eye disorders using NGS panels and aCGH along with additional complementary testing may often be required to arrive at a definitive diagnosis
Ion observations from geosynchronous orbit as a proxy for ion cyclotron wave growth during storm times
[1] There is still much to be understood about the processes contributing to relativistic electron enhancements and losses in the radiation belts. Wave particle interactions with both whistler and electromagnetic ion cyclotron (EMIC) waves may precipitate or accelerate these electrons. This study examines the relation between EMIC waves and resulting relativistic electron flux levels after geomagnetic storms. A proxy for enhanced EMIC waves is developed using Los Alamos National Laboratory Magnetospheric Plasma Analyzer plasma data from geosynchronous orbit in conjunction with linear theory. In a statistical study using superposed epoch analysis, it is found that for storms resulting in net relativistic electron losses, there is a greater occurrence of enhanced EMIC waves. This is consistent with the hypothesis that EMIC waves are a primary mechanism for the scattering of relativistic electrons and thus cause losses of such particles from the magnetosphere
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