0000000001053025

AUTHOR

Alex Parker

Inflight Radiometric Calibration of New Horizons' Multispectral Visible Imaging Camera (MVIC)

© 2016 Elsevier Inc. We discuss two semi-independent calibration techniques used to determine the inflight radiometric calibration for the New Horizons’ Multi-spectral Visible Imaging Camera (MVIC). The first calibration technique compares the measured number of counts (DN) observed from a number of well calibrated stars to those predicted using the component-level calibration. The ratio of these values provides a multiplicative factor that allows a conversation between the preflight calibration to the more accurate inflight one, for each detector. The second calibration technique is a channel-wise relative radiometric calibration for MVIC's blue, near-infrared and methane color channels us…

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Col-OSSOS: Colours of the Outer Solar System Origins Survey

International audience; The surfaces of trans-Neptunian objects (TNOs) are poorly understood. Other than the large objects which exhibit signatures of various ices, very little has been discerned about the compositions of most TNOs. In recent years, some concrete knowledge about the distribution of surface colours of small TNOs has come to light. It is now generally accepted that small TNOs fall into at least three classes of object based on their surface colours and albedo. TNO surface type is also correlated with dynamical class, with certain types of TNO being found primarily in certain regions of the outer Solar System. This correlation presents the intriguing idea that the surfaces of …

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Genetic associations at 53 loci highlight cell types and biological pathways relevant for kidney function

Reduced glomerular filtration rate defines chronic kidney disease and is associated with cardiovascular and all-cause mortality. We conducted a meta-analysis of genome-wide association studies for estimated glomerular filtration rate (eGFR), combining data across 133,413 individuals with replication in up to 42,166 individuals. We identify 24 new and confirm 29 previously identified loci. Of these 53 loci, 19 associate with eGFR among individuals with diabetes. Using bioinformatics, we show that identified genes at eGFR loci are enriched for expression in kidney tissues and in pathways relevant for kidney development and transmembrane transporter activity, kidney structure, and regulation o…

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New loci associated with kidney function and chronic kidney disease

Chronic kidney disease (CKD) is a significant public health problem, and recent genetic studies have identified common CKD susceptibility variants. The CKDGen consortium performed a meta-analysis of genome-wide association data in 67,093 individuals of European ancestry from 20 predominantly population-based studies in order to identify new susceptibility loci for reduced renal function as estimated by serum creatinine (eGFRcrea), serum cystatin c (eGFRcys) and CKD (eGFRcrea 60 ml/min/1.73 m 2; n = 5,807 individuals with CKD (cases)). Follow-up of the 23 new genome-wide-significant loci (P 5 × 10 8) in 22,982 replication samples identified 13 new loci affecting renal function and CKD (in or…

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Meta-Analysis of Genome-Wide Association Studies in >80 000 Subjects Identifies Multiple Loci for C-Reactive Protein Levels

Background— C-reactive protein (CRP) is a heritable marker of chronic inflammation that is strongly associated with cardiovascular disease. We sought to identify genetic variants that are associated with CRP levels. Methods and Results— We performed a genome-wide association analysis of CRP in 66 185 participants from 15 population-based studies. We sought replication for the genome-wide significant and suggestive loci in a replication panel comprising 16 540 individuals from 10 independent studies. We found 18 genome-wide significant loci, and we provided evidence of replication for 8 of them. Our results confirm 7 previously known loci and introduce 11 novel loci that are implicated in p…

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