University of Saint Mary

About: University of Saint Mary is a education organization based out in Leavenworth, Kansas, United States. It is known for research contribution in the topics: Population & Galaxy. The organization has 2276 authors who have published 2399 publications receiving 58990 citations. The organization is also known as: University of St. Mary & University of St Mary.

Outside the Lyman-break box: detecting Lyman continuum emitters at 3.5 < z < 5.1 with CLAUDS

Abstract: Identifying non-contaminated sample of high-redshift galaxies with escaping Lyman continuum (LyC) flux is important for understanding the sources and evolution of cosmic reionization. We present CLAUDS (CFHT Large Area u-band deep survey) u-band photometry of the COSMOS field to probe LyC radiation from spectroscopically confirmed galaxies at z ≥ 3.5 and outside the standard Lyman-break galaxy colour-selection expectations. Complementary to the CLAUDS data, we use Subaru multifilter photometry, Hubble Space Telescope (HST) multifilter imaging, and the spectroscopic surveys D10K, VUDS, and 3D-HST. We present a sample of Lyman continuum galaxy (LCG) candidates in the redshift range 3.5 ≲ z ≲ 5.1. Here, we introduce 5 LCG candidates, where two are flagged quality 1 and three quality 2. The estimated f^(abs)_(esc) for quality 1 candidates are in the range ∼5−73 per cent and ∼30−93 per cent⁠. These estimates are based on our derived parameters from individual galaxies as inputs to a range of BPASS models as well as mean intergalactic medium (IGM) and maximal intergalactic and circumgalactic media (IGM+CGM) transmission. We conclude that our search for LCGs is most likely biased to lines of sight with low H I densities or free from Lyman limit systems. Our two best LCG candidates have EW (Lyα) ≤ 50 A and we find no correlation or anticorrelation between EW (Lyα), f^(abs)_(esc), and Robs, the ratio of ionizing to non-ionizing observed flux in the measured passbands. Stacking candidates without solid LyC detections (S/N < 3) results in an estimated f^(abs)_(esc) from galaxies not greater than 1 per cent⁠.

Adrenomedullary secretion of DOPA, catecholamines, catechol metabolites, and neuropeptides

Abstract: Catecholamines and their metabolites have been proposed as markers of sympathetic nervous system stimulation. However, the adrenal medulla is a rich source of catecholamines and catecholamine metabolites and may play a significant role in plasma levels of these compounds. In addition to adrenal catecholamine metabolite efflux, the role of the catecholamine precursor 3,4-dihydroxyphenylalanine (DOPA) has not been fully evaluated. The simultaneous effluxes of catecholamines, metabolites, DOPA, and neuropeptides were measured in perfusates from isolated dog adrenals. The relative abundance of compounds detected consistently during unstimulated conditions was epinephrine >> norepinephrine > 3,4-dihydroxyphenylglycol > metanephrine > normetanephrine > dopamine > 3,4-dihydroxyphenylacetic acid > 3-methoxy-4-hydroxyphenylglycol > or = DOPA >> [Met]enkephalin >> neuropeptide Y. Effluxes of analytes were not affected by cocaine and the ratios of catecholamines to metabolites increased dramatically with carbachol stimulation, consistent with negligible reuptake into adrenal cells. Thus, most of the 3,4-dihydroxyphenylglycol is expected to be derived from epinephrine and norepinephrine subsequent to translocation from chromaffin vesicles into the cytosol. The efflux of DOPA increased dramatically during stimulation with 30 microM carbachol in a calcium-dependent manner. Efflux of DOPA during the initial stabilization period of the perfusion preparation declined exponentially, in parallel with the effluxes of the catecholamines and neuropeptides but not with metabolites. Evoked release of DOPA was Ca2+-dependent. These data suggest that DOPA can be stored and released exocytotically from chromaffin granules.