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ARMC 5 Variants and Risk of Hypertension in Blacks: MH- GRID Study.
Background We recently found that ARMC 5 variants may be associated with primary aldosteronism in blacks. We investigated a cohort from the MH - GRID (Minority Health Genomics and Translational Research Bio-Repository Database) and tested the association between ARMC 5 variants and blood pressure in black s. Methods and Results Whole exome sequencing data of 1377 black s were analyzed. Target single-variant and gene-based association analyses of hypertension were performed for ARMC 5, and replicated in a subset of 3015 individuals of African descent from the UK Biobank cohort. Sixteen rare variants were significantly associated with hypertension ( P=0.0402) in the gene-based (optimized sequenced kernel association test) analysis; the 16 and one other, rs116201073, together, showed a strong association ( P=0.0003) with blood pressure in this data set. The presence of the rs116201073 variant was associated with lower blood pressure. We then used human embryonic kidney 293 and adrenocortical H295R cells transfected with an ARMC 5 construct containing rs116201073 (c.*920T>C). The latter was common in both the discovery ( MH - GRID ) and replication ( UK Biobank) data and reached statistical significance ( P=0.044 [odds ratio, 0.7] and P=0.007 [odds ratio, 0.76], respectively). The allele carrying rs116201073 increased levels of ARMC5 mRNA , consistent with its protective effect in the epidemiological data. Conclusions ARMC 5 shows an association with hypertension in black s when rare variants within the gene are considered. We also identified a protective variant of the ARMC 5 gene with an effect on ARMC 5 expression confirmed in vitro. These results extend our previous report of ARMC 5's possible involvement in the determination of blood pressure in blacks
Intercalibration of the barrel electromagnetic calorimeter of the CMS experiment at start-up
Calibration of the relative response of the individual channels of the barrel electromagnetic calorimeter of the CMS detector was accomplished, before installation, with cosmic ray muons and test beams. One fourth of the calorimeter was exposed to a beam of high energy electrons and the relative calibration of the channels, the intercalibration, was found to be reproducible to a precision of about 0.3%. Additionally, data were collected with cosmic rays for the entire ECAL barrel during the commissioning phase. By comparing the intercalibration constants obtained with the electron beam data with those from the cosmic ray data, it is demonstrated that the latter provide an intercalibration precision of 1.5% over most of the barrel ECAL. The best intercalibration precision is expected to come from the analysis of events collected in situ during the LHC operation. Using data collected with both electrons and pion beams, several aspects of the intercalibration procedures based on electrons or neutral pions were investigated
Technical note: development of a 3D printed subresolution sandwich phantom for validation of brain SPECT analysis
Purpose: To make an adaptable, head shaped radionuclide phantom to simulate molecular imaging of the brain using clinical acquisition and reconstruction protocols. This will allow the characterization and correction of scanner characteristics, and improve the accuracy of clinical image analysis, including the application of databases of normal subjects. Methods: A fused deposition modeling 3D printer was used to create a head shaped phantom made up of transaxial slabs, derived from a simulated MRI dataset. The attenuation of the printed polylactide (PLA), measured by means of the Hounsfield unit on CT scanning, was set to match that of the brain by adjusting the proportion of plastic filament and air (fill ratio). Transmission measurements were made to verify the attenuation of the printed slabs. The radionuclide distribution within the phantom was created by adding 99mTc pertechnetate to the ink cartridge of a paper printer and printing images of gray and white matter anatomy, segmented from the same MRI data. The complete subresolution sandwich phantom was assembled from alternate 3D printed slabs and radioactive paper sheets, and then imaged on a dual headed gamma camera to simulate an HMPAO SPECT scan. Results: Reconstructions of phantom scans successfully used automated ellipse fitting to apply attenuation correction. This removed the variability inherent in manual application of attenuation correction and registration inherent in existing cylindrical phantom designs. The resulting images were assessed visually and by count profiles and found to be similar to those from an existing elliptical PMMA phantom. Conclusions: The authors have demonstrated the ability to create physically realistic HMPAO SPECT simulations using a novel head-shaped 3D printed subresolution sandwich method phantom. The phantom can be used to validate all neurological SPECT imaging applications. A simple modification of the phantom design to use thinner slabs would make it suitable for use in PET
Dilepton production in heavy ion collisions at intermediate energies
We present a unified description of the vector meson and dilepton production
in elementary and in heavy ion reactions. The production of vector mesons
() is described via the excitation of nuclear resonances ().
The theoretical framework is an extended vector meson dominance model (eVMD).
The treatment of the resonance decays with arbitrary spin is
covariant and kinematically complete. The eVMD includes thereby excited vector
meson states in the transition form factors. This ensures correct asymptotics
and provides a unified description of photonic and mesonic decays. The
resonance model is successfully applied to the production in
reactions. The same model is applied to the dilepton production in elementary
reactions (). Corresponding data are well reproduced. However, when
the model is applied to heavy ion reactions in the BEVALAC/SIS energy range the
experimental dilepton spectra measured by the DLS Collaboration are
significantly underestimated at small invariant masses. As a possible solution
of this problem the destruction of quantum interference in a dense medium is
discussed. A decoherent emission through vector mesons decays enhances the
corresponding dilepton yield in heavy ion reactions. In the vicinity of the
-peak the reproduction of the data requires further a substantial
collisional broadening of the and in particular of the meson.Comment: 32 pages revtex, 19 figures, to appear in PR
Ambiguity functions, groups of transformations and time-frequency displacement operators. Part I
We review in this first part the connections between ambiguity functions and groups of transformations. Starting
from the original definition of the ambiguity function we study its generalisations as associated with various situations,
as well as their underlying groups, in particular by characterising the group of general bijective transformations
of the time axis (warpings), adapted to point-like targets of arbitrary motion, and the group of linear transformations
of the time frequency plane, which will be studied in the second part. We address the question of when
an ambiguity function completely determines the waveform and may be optimally chosen. It is shown that groups
which yield a finite ambiguity domain are two-parameter groups.Cette première partie passe en revue les relations qui existent entre fonctions d'ambiguïté et groupes de transformations. On part de la définition première de la fonction d'ambiguïté pour étudier ses généralisations associées à divers types de situations, ainsi que les groupes sur lesquels elles se basent, en particulier on introduit le groupe des transformations bijectives quelconques de l'axe des temps (changements d'horloge), adapté aux cibles ponctuelles de mouvement quelconque, et celui des transformations linéaires du plan temps fréquence, qui seront étudiés dans la seconde partie. On examine dans quel cas la fonction d'ambiguïté détermine entièrement la forme d'onde, et peut être choisie de manière optimale. On montre que les groupes qui permettent de déterminer un domaine d'ambiguïté fini associé à un signal sont à deux paramètres
Integral equations for axisymmetric problems
Wave scattering by obstacles leads to systems of integral equations for unknown fonctions defined on a surface . We show that
axisymmetric problems may be reduced to integral equations for unknown functions of a single variable, with a computational
gain. The singular kernels relevant to the integral operators of acoustics and electromagnetism are written explicitly and their
properties studied ; methods are provided for their efficient computation . As an example we take a conical corrugated horn and
determine, via a calculation of the superficial currents, its radiation patterns and standing wave ratio.Diffusion des ondes acoustiques et électromagnétiques par des corps de révolutio
Forced Solid-State Interactions for the Selective “Turn-On” Fluorescence Sensing of Aluminum Ions in Water Using a Sensory Polymer Substrate
Selective and sensitive solid sensory substrates for detecting Al(III) in pure
water are reported. The material is a flexible polymer film that can be handled and exhibits gel
behavior and membrane performance. The film features a chemically anchored salicylaldehyde
benzoylhydrazone derivative as an aluminum ion fluorescence sensor. A novel procedure for
measuring Al(III) at the ppb level using a single solution drop in 20 min was developed. In this
procedure, a drop was allowed to enter the hydrophilic material for 15 min before a 5 min
drying period. The process forced the Al(III) to interact with the sensory motifs within the
membrane before measuring the fluorescence of the system. The limit of detection of Al(III)
was 22 ppm. Furthermore, a water-soluble sensory polymer containing the same sensory
motifs was developed with a limit of detection of Al(III) of 1.5 ppb, which was significantly
lower than the Environmental Protection Agency recommendations for drinking water.Spanish Ministerio de Economía
y Competitividad-Feder
(MAT2011-22544) and by the Consejería
de Educación - Junta
de Castilla y León (BU232U13)
Extraction of Nitric Acid, Americium(III), Curium(III), and Lanthanides(III) into DMDOHEMA Dissolved in Kerosene
Enhancing organisational competitiveness via social media - a strategy as practice perspective
The affordances, popularity and pervasive use of social media platforms such as Facebook, Twitter and Instagram have made these platforms attractive to organisations for enhancing their competitiveness and creating business value. Despite this apparent significance of social media for businesses, they are struggling with the development of a social media strategy as well as understanding the implications of social media on practice within their organisations. This paper explores how social media has become a tool for competitiveness and its influence on organisational strategy and practice. Using the 'strategy as practice' lens and guided by the interpretivist philosophy, this paper uses the empirical case of a telecom organisation in Tanzania. The findings show that social media is influencing competitiveness through imitation and product development. Also, the findings indicate how social media affects the practices within an organisation, consequently making the social media strategy an emergent phenomenon
They are not all same: variations in Asian consumers' value perceptions of luxury brands
Asian markets are steadily becoming key growth regions for luxury brands. However, despite the growth, many luxury brand firms are unable to obtain the desired economic returns through their marketing strategies in Asia. Often these firms treat consumers across Asian markets as homogenous groups, which could lead to inaccurate luxury brand management strategy. Additionally, there is limited understanding of consumer value perceptions toward luxury brands across the Asian markets. Employing impression management theory and the horizontal/vertical collectivistic cultural distinctions, this study examines differences and similarities in constituent luxury value perceptions across three prominent Asian markets, namely China, India, and Indonesia. The results of a quantitative survey conducted with 626 real luxury consumers in these three countries identify variations in perceptions of symbolic, experiential, and functional value of luxury brands. The study contributes to knowledge on constituent luxury value perceptions, along with providing theoretical explanations for the differences between consumers across Asian markets. With the emerging novel insights on Asian consumers, luxury brand firms can align their marketing strategies to respective markets by leveraging the similarities and differences in consumer value perceptions. This approach, informed by empirical evidence, will enhance luxury brands’ competitiveness and profit opportunities in the high-growth Asian markets. The study identifies a number of future research directions
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