1,200 research outputs found
Giant Cell Arteritis: Clinical Guide for the Eyecare Professional
Purpose The purpose of this article is to review giant cell arteritis, with a focus on ophthalmic manifestations, and provide a quick reference for clinical identification, diagnosis and appropriate management.
Summary Giant cell arteritis is one of a few true medical emergencies that may present initially to the eyecare professional. Understanding the clinical picture of disease course and management arms the eyecare professional with the ability to detect and manage early in the disease process, potentially preventing blindness and life-threatening systemic manifestations
Abell 2111: An Optical and Radio Study of the Richest Butcher-Oemler Cluster
We present an in-depth analysis of the Butcher-Oemler cluster A2111,
including new optical spectroscopy plus a deep Very Large Array (VLA) radio
continuum observation. These are combined with optical imaging from the Sloan
Digital Sky Survey (SDSS) to assess the activity and properties of member
galaxies. Prior X-ray studies have suggested A2111 is a head-on cluster merger,
a dynamical state which might be connected to the high level of activity
inferred from its blue fraction. We are able to directly assess this claim,
using our spectroscopic data to identify 95 cluster members among 196 total
galaxy spectra. These galaxy velocities do not themselves provide significant
evidence for the merger interpretation, however they are consistent with it
provided the system is viewed near the time of core passage and at a viewing
angle >~30 degrees different from the merger axis. The SDSS data allow us to
confirm the high blue fraction for A2111, f_b = 0.15 +/- 0.03 based on
photometry alone and f_b = 0.23 +/- 0.03 using spectroscopic data to remove
background galaxies. We are able to detect 175 optical sources from the SDSS in
our VLA radio data, of which 35 have redshift information. We use the SDSS
photometry to determine photometric redshifts for the remaining 140
radio-optical sources. In total we identify up to 26 cluster radio galaxies, 14
of which have spectroscopic redshifts. The optical spectroscopy and radio data
reveal a substantial population of dusty starbursts within the cluster. The
high blue fraction and prevalence of star formation is consistent with the
hypothesis that dynamically-active clusters are associated with more active
member galaxies than relaxed clusters.Comment: To appear in AJ; 53 pages including 10 figures and several long
table
Experimental Evaluation of High Performance Integrated Heat Pump
Integrated heat pump (IHP) technology provides significant potential for energy savings and comfort improvement for residential buildings. In this study, we evaluate the performance of a high performance IHP that provides space heating, cooling, and water heating services. Experiments were conducted according to the ASHRAE Standard 206-2013 where 24 test conditions were identified in order to evaluate the IHP performance indices. An 8-in by 8-in Air Monitor Fan Evaluator is used to measure the volumetric flowrate of air discharged from the air handler unit (AHU) in order to evaluate the airside performance. Empirical curve fits of the unit’s compressor maps are used in conjunction with saturated condensing and evaporating refrigerant conditions to deduce the refrigerant mass flowrate, which, in turn is used to evaluate the refrigerant-side performance. Heat pump (compressor, fans, and controls) and water pump power were measured separately per requirements of Standard 206. The system was charged per the system manufacturer’s specifications. System test results are presented for each operating mode along with overall IHP performance metrics according to ASHRAE standard 206-2013. The paper ends with discussion on system operation and impact on typical energy consumption in residential buildings
Adenosine echocardiography with or without handgrip in the diagnosis of coronary artery disease: Comparison with exercise echocardiography
Artérite temporale ou maladie de Horton : Guide clinique du professionnel des soins oculovisuels
Objet Le présent article a pour but de passer en revue la problématique de l’artérite temporale, en mettant l’accent sur les manifestations ophtalmiques, et de fournir un guide de référence rapide pour l’identification clinique, le diagnostic et la prise en charge appropriée.
Résumé L’artérite temporale est l’une des rares urgences médicales qui peut amener un patient à se présenter initialement chez un professionnel des soins oculovisuels. La compréhension de l’évolution de la maladie et de sa prise en charge aidera le professionnel des soins oculovisuels à la détecter et à la prendre en charge tôt dans le processus, pouvant ainsi prévenir la cécité et des manifestations systémiques potentiellement mortelles
Using Pressure- and Temperature-Sensitive Paint for Global Surface Pressure and Temperature Measurements on the Aft-Body of a Capsule Reentry Vehicle
Pressure Sensitive Paint (PSP) and Temperature Sensitive Paint (TSP) were used to visualize and quantify the surface interactions of reaction control system (RCS) jets on the aft body of capsule reentry vehicle shapes. The first model tested was an Apollo-like configuration and was used to focus primarily on the effects of the forward facing roll and yaw jets. The second model tested was an early Orion Crew Module configuration blowing only out of its forward-most yaw jet, which was expected to have the most intense aerodynamic heating augmentation on the model surface. This paper will present the results from the experiments, which show that with proper system design, both PSP and TSP are effective tools for studying these types of interaction in hypersonic testing environments
Development of a Pressure Sensitive Paint System for Measuring Global Surface Pressures on Rotorcraft Blades
This paper will describe the results from a proof of concept test to examine the feasibility of using Pressure Sensitive Paint (PSP) to measure global surface pressures on rotorcraft blades in hover. The test was performed using the U.S. Army 2-meter Rotor Test Stand (2MRTS) and 15% scale swept rotor blades. Data were collected from five blades using both the intensity- and lifetime-based approaches. This paper will also outline several modifications and improvements that are underway to develop a system capable of measuring pressure distributions on up to four blades simultaneously at hover and forward flight conditions
Estrogen-Induced Relaxation in Bovine Coronary Arteries in vitro: Evidence for a New Mechanism
Numerous studies have shown estrogen to be vasoactive in various circulations. Our objective was to determine the effect of estrogen on isolated bovine coronary arteries and the possible mechanism. Bovine coronary arteries, precontracted with thromboxane mimetic U46619 were given doses (0.01-30μM) of 17Β-estradiol in the presence and absence of endothelium and these inhibitors: 10μM indomethacin (cyclooxygenase inhibitor), 10μM methylene blue (inhibits soluble guanylate cyclase), 100μM nitro-L-arginine (inhibits nitric oxide synthesis), 100μM isobutylmethylxanthine (phosphodiesterase inhibitor) and 30μM mifepristone (Ru38486 steroid receptor antagonist). Our results indicated that, estrogen, in the highest concentration used (30μM), elicited an acute dose-dependent relaxation of bovine coronary arteries from 4%-68% (n=15). No major difference in relaxation was observed between coronary arteries with or without endothelium, indicating that the mechanism was endotheliumindependent. Indomethacin, nitro-L-arginine and methylene blue did not alter this relaxation, suggesting that relaxant prostaglandins, 1-arginine products and cGMP are not involved (n=11-16), isobutylmethylxanthine enhanced relaxation from 20%-40% (n=15 p\u3c0.01), suggests a role for cAMP. Furthermore, mifepristone reduced the relaxation by more than 50% (n=15 p\u3c0.05) consistent with the role for estrogen receptors. Based on our study, estrogen causes a dosedependent relaxation of bovine coronary arteries that does not appear to utilize endothelium, prostaglandins, cGMP or arginine products, but may involve cAMP and estrogen receptors. This study may help justify treating myocardial ischemia with estrogen
A New Moderately Repetitive DNA Sequence Family of Novel Organization
In cloning adenovirus homologous sequences, from a human cosmid library, we identified a moderately repetitive DNA sequence family consisting of tandem arrays of 2.5 kb members. A member was sequenced and several non-adjacent, 15–20 bp G-C rich segments with homology to the left side of adenovirus were discovered. The copy number of 400 members is highly conserved among humans. Southern blots of partial digests of human DNA have verified the tandem array of the sequence family. The chromosomal location was defined by somatic cell genetics and in situ hybridization. Tandem arrays are found only on chromosomes 4 (4q31) and 19 (ql3.l-ql3.3). Homologous repetitive sequences are found in DNA of other primates but not in cat or mouse. Thus we have identified a new family of moderately repetitive DNA sequences, unique because of its organization in clustered tandem arrays, its length, its chromosomal location, and its lack of homology to other moderately repetitive sequence families
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