178 research outputs found
Metabolic Cardiomyopathies and Cardiac Defects in Inherited Disorders of Carbohydrate Metabolism:A Systematic Review
Heart failure (HF) is a progressive chronic disease that remains a primary cause of death worldwide, affecting over 64 million patients. HF can be caused by cardiomyopathies and congenital cardiac defects with monogenic etiology. The number of genes and monogenic disorders linked to development of cardiac defects is constantly growing and includes inherited metabolic disorders (IMDs). Several IMDs affecting various metabolic pathways have been reported presenting cardiomyopathies and cardiac defects. Considering the pivotal role of sugar metabolism in cardiac tissue, including energy production, nucleic acid synthesis and glycosylation, it is not surprising that an increasing number of IMDs linked to carbohydrate metabolism are described with cardiac manifestations. In this systematic review, we offer a comprehensive overview of IMDs linked to carbohydrate metabolism presenting that present with cardiomyopathies, arrhythmogenic disorders and/or structural cardiac defects. We identified 58 IMDs presenting with cardiac complications: 3 defects of sugar/sugar-linked transporters (GLUT3, GLUT10, THTR1); 2 disorders of the pentose phosphate pathway (G6PDH, TALDO); 9 diseases of glycogen metabolism (GAA, GBE1, GDE, GYG1, GYS1, LAMP2, RBCK1, PRKAG2, G6PT1); 29 congenital disorders of glycosylation (ALG3, ALG6, ALG9, ALG12, ATP6V1A, ATP6V1E1, B3GALTL, B3GAT3, COG1, COG7, DOLK, DPM3, FKRP, FKTN, GMPPB, MPDU1, NPL, PGM1, PIGA, PIGL, PIGN, PIGO, PIGT, PIGV, PMM2, POMT1, POMT2, SRD5A3, XYLT2); 15 carbohydrate-linked lysosomal storage diseases (CTSA, GBA1, GLA, GLB1, HEXB, IDUA, IDS, SGSH, NAGLU, HGSNAT, GNS, GALNS, ARSB, GUSB, ARSK). With this systematic review we aim to raise awareness about the cardiac presentations in carbohydrate-linked IMDs and draw attention to carbohydrate-linked pathogenic mechanisms that may underlie cardiac complications.</p
Erythropoietin and Anaemia in Patients with Chronic Renal Failure
Hyporegenerative anaemia is common complication of chronic renal failure CRF and responsible for fatigue and reduced general health condition among uremic patient. The main causes of anemia among patients with chronic renal failure are deficient production of erythropoietin (EPO), iron deficiency, and chronic disease with endogenous EPO resistance. This study confirmed on patients with chronic renal failure in Merjan Teaching Hospital and highlighted on the relationship between anaemia and erythropoiten level. The estimation of hemoglobin among patients with CRF revealed that 55% of patients suffered from severe anaemia and 45%suffered from moderate anaemia     Erythropoiten level estimated by ELISA technique and mean and standard deviation of erythropoietin level among patients and control groups were12.2 uU/ml ± 2.6, 7.3uU/ml± 1.8 respectively and comparism mean of erythropoietin between patients and control group  was indicated that there is significant difference between two groups at p value< 0.05 By study the correlation between hemoglobin and erythropoietin revealed that there is inverses relation ship between hemoglobin and erythropoietin , we concluded from this study although the level of erythropoietin increase in patients with CRF but the level of erythropoietin are not enough foe correction of anaemia and patient may required for exogenous source for erythropoietin with iron supplement in management of anaemia Keywords: erythropoiten Hyporegenerative anaemi
Topological descriptors for 3D surface analysis
We investigate topological descriptors for 3D surface analysis, i.e. the
classification of surfaces according to their geometric fine structure. On a
dataset of high-resolution 3D surface reconstructions we compute persistence
diagrams for a 2D cubical filtration. In the next step we investigate different
topological descriptors and measure their ability to discriminate structurally
different 3D surface patches. We evaluate their sensitivity to different
parameters and compare the performance of the resulting topological descriptors
to alternative (non-topological) descriptors. We present a comprehensive
evaluation that shows that topological descriptors are (i) robust, (ii) yield
state-of-the-art performance for the task of 3D surface analysis and (iii)
improve classification performance when combined with non-topological
descriptors.Comment: 12 pages, 3 figures, CTIC 201
Structure of the X-ray Emission from the Jet of 3C 273
We present images from five observations of the quasar 3C 273 with the
Chandra X-ray Observatory. The jet has at least four distinct features which
are not resolved in previous observations. The first knot in the jet (A1) is
very bright in X-rays. Its X-ray spectrum is well fitted with a power law with
alpha = 0.60 +/- 0.05. Combining this measurement with lower frequency data
shows that a pure synchrotron model can fit the spectrum of this knot from
1.647 GHz to 5 keV (over nine decades in energy) with alpha = 0.76 +/- 0.02,
similar to the X-ray spectral slope. Thus, we place a lower limit on the total
power radiated by this knot of 1.5e43 erg/s; substantially more power may be
emitted in the hard X-ray and gamma-ray bands.
Knot A2 is also detected and is somewhat blended with knot B1. Synchrotron
emission may also explain the X-ray emission but a spectral bend is required
near the optical band. For knots A1 and B1, the X-ray flux dominates the
emitted energy. For the remaining optical knots (C through H), localized X-ray
enhancements that might correspond to the optical features are not clearly
resolved. The position angle of the jet ridge line follows the optical shape
with distinct, aperiodic excursions of +/-1 deg from a median value of
-138.0deg. Finally, we find X-ray emission from the ``inner jet'' between 5 and
10" from the core.Comment: 10 pages, 5 figures; accepted for publication in the Astrophysical
Journal Letters. For the color image, see fig1.ps or
http://space.mit.edu/~hermanm/papers/3c273/fig1.jp
Measurement report: Receptor modeling for source identification of urban fine and coarse particulate matter using hourly elemental composition
The elemental composition of the fine (PM2.5) and coarse
(PM2.5−10) fraction of atmospheric particulate matter was measured at an hourly time resolution by the use of a streaker sampler during a winter
period at a Central European urban background site in Warsaw, Poland. A
combination of multivariate (Positive Matrix Factorization) and wind-
(Conditional Probability Function) and trajectory-based (Cluster Analysis)
receptor models was applied for source apportionment. It allowed for the
identification of five similar sources in both fractions, including sulfates, soil dust, road salt, and traffic- and industry-related sources. Another two sources, i.e., Cl-rich and wood and coal combustion, were solely identified in the fine fraction. In the fine fraction, aged sulfate aerosol related to emissions from domestic solid fuel combustion in the outskirts of the city was the largest contributing source to fine elemental mass (44 %), while traffic-related sources, including soil dust mixed with road dust, road dust, and traffic emissions, had the biggest contribution to the coarse elemental mass (together accounting for 83 %). Regional transport of aged aerosols and more local impact of the rest of the identified sources played a crucial role in aerosol formation over the city. In addition, two intensive Saharan dust outbreaks were registered on 18 February and 8 March 2016. Both episodes were characterized by the long-range transport of dust at 1500 and 3000 m over Warsaw and the concentrations of the soil component being 7 (up to 3.5 µg m−3) and 6 (up to 6.1 µg m−3) times higher than the mean concentrations observed during non-episodes days (0.5 and 1.1 µg m−3) in the fine and coarse fractions, respectively. The set of receptor models applied to the high time resolution data allowed us to follow, in detail, the daily evolution of the aerosol elemental composition and to identify distinct sources contributing to the concentrations of the different PM fractions, and it revealed the multi-faceted nature of some elements with diverse origins in the fine and coarse fractions. The hourly resolution of meteorological conditions and air mass back trajectories allowed us to follow the transport pathways of the aerosol as well.</p
Precise U-Pb zircon ages and geochemistry of Jurassic granites, Ellsworth-Whitmore terrane, central Antarctica
The Ellsworth-Whitmore Mountain terrane of central Antarctica was part of the early Paleozoic amalgamation of Gondwana, including a 13,000 m section of Cambrian–Permian sediments in the Ellsworth Mountains deposited on Grenville-age crust. The Jurassic breakup of Gondwana involved a regional, bimodal magmatic event during which the Ellsworth-Whitmore terrane was intruded by intraplate granites before translation of the terrane to its present location in central Antarctica. Five widely separated granitic plutons in the Ellsworth-Whitmore terrane were analyzed for their whole-rock geochemistry (X-ray fluorescence), Sr, Nd, and Pb isotopic compositions, and U-Pb zircon ages to investigate the origins of the terrane magmas and their relationships to mafic magmatism of the 183 Ma Karoo-Ferrar large igneous province (LIP). We report high-precision (±0.1 m.y.) isotope dilution–thermal ionization mass spectrometry (ID-TIMS) U-Pb zircon ages from granitic rocks from the Whitmore Mountains (208.0 Ma), Nash Hills (177.4–177.3 Ma), Linck Nunatak (175.3 Ma), Pagano Nunatak (174.8 Ma), and the Pirrit Hills (174.3–173.9 Ma), and U-Pb sensitive high-resolution ion microprobe (SHRIMP) ages from the Whitmore Mountains (200 ± 5 Ma), Linck Nunatak (180 ± 4 Ma), Pagano Nunatak (174 ± 4 Ma), and the Pirrit Hills (168 ± 4 Ma). We then compared these results with existing K-Ar ages and Nd model ages, and used initial Sr, Nd, and Pb isotope ratios, combined with xenocrystic zircon U-Pb inheritance, to infer characteristics of the source(s) of the parent magmas. We conclude that the Jurassic plutons were not derived exclusively from crustal melts, but rather they are hybridized magmas composed of convecting mantle, subcontinental lithospheric mantle, and lower continental crustal contributions. The mantle contributions to the granites share isotopic similarities to the sources of other Jurassic LIP mafic magmas, including radiogenic 87Sr/86Sr (0.706–0.708), unradiogenic 143Nd/144Nd (εNd < –5), and Pb isotopes consistent with a low-µ source (where μ = 238U/204Pb). Isotopes and zircon xenocrysts point toward a crustal end member of predominantly Proterozoic provenance (0.5–1.0 Ga; Grenville crust), extending the trends illustrated by Ferrar mafic intrusive rocks, but contrasting with the inferred Archean crustal and/or lithospheric mantle contributions to some basalts of the Karoo sector of the LIP. The Ellsworth-Whitmore terrane granites are the result of mafic rocks underplating the hydrous crust, causing crustal melting, hybridization, and fractionation to produce granitic magmas that were eventually emplaced as post-Ferrar, within-plate melts at higher crustal levels as the Ellsworth-Whitmore terrane rifted off Gondwana (47°S) before migrating to its current position (82°S) in central Antarctica
First Light Measurements of Capella with the Low Energy Transmission Grating Spectrometer aboard the Chandra X-ray Observatory
We present the first X-ray spectrum obtained by the Low Energy Transmission
Grating Spectrometer (LETGS) aboard the Chandra X-ray Observatory. The spectrum
is of Capella and covers a wavelength range of 5-175 A (2.5-0.07 keV). The
measured wavelength resolution, which is in good agreement with ground
calibration, is 0.06 A (FWHM). Although in-flight
calibration of the LETGS is in progress, the high spectral resolution and
unique wavelength coverage of the LETGS are well demonstrated by the results
from Capella, a coronal source rich in spectral emission lines. While the
primary purpose of this letter is to demonstrate the spectroscopic potential of
the LETGS, we also briefly present some preliminary astrophysical results. We
discuss plasma parameters derived from line ratios in narrow spectral bands,
such as the electron density diagnostics of the He-like triplets of carbon,
nitrogen, and oxygen, as well as resonance scattering of the strong Fe XVII
line at 15.014 A.Comment: 4 pages (ApJ letter LaTeX), 2 PostScript figures, accepted for
publication in ApJ Letters, 200
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