A load-locked gun for the Jefferson Lab polarized injector

Construction is underway at Jefferson Lab on a load-locked polarized electron source. The design incorporates all of the essential features of the existing non load-locked gun and improves on the designs of existing load-locked guns operating at other labs. When complete, the authors expect the new load-locked gun to enhance the versatility of the JLAB polarized injector

Characterization of Two 2 mm detected Optically Obscured Dusty Star-forming Galaxies

International audienceThe 2 mm Mapping Obscuration to Reionization with ALMA (MORA) Survey was designed to detect high-redshift (z ≳ 4), massive, dusty star-forming galaxies (DSFGs). Here we present two likely high-redshift sources, identified in the survey, whose physical characteristics are consistent with a class of optical/near-infrared (OIR)-invisible DSFGs found elsewhere in the literature. We first perform a rigorous analysis of all available photometric data to fit spectral energy distributions and estimate redshifts before deriving physical properties based on our findings. Our results suggest the two galaxies, called MORA-5 and MORA-9, represent two extremes of the "OIR-dark" class of DSFGs. MORA-5 ( ${z}_{\mathrm{phot}}={4.3}_{-1.3}^{+1.5}$ ) is a significantly more active starburst with a star formation rate (SFR) of ${830}_{-190}^{+340}$ M ⊙ yr-1 compared to MORA-9 ( ${z}_{\mathrm{phot}}={4.3}_{-1.0}^{+1.3}$ ), whose SFR is a modest ${200}_{-60}^{+250}$ M ⊙ yr-1. Based on the stellar masses (M ⋆ ≍ 1010-11 M ⊙), space density (n ~ (5 ± 2) × 10-6 Mpc-3, which incorporates two other spectroscopically confirmed OIR-dark DSFGs in the MORA sample at z = 4.6 and z = 5.9), and gas depletion timescales (<1 Gyr) of these sources, we find evidence supporting the theory that OIR-dark DSFGs are the progenitors of recently discovered 3 < z < 4 massive quiescent galaxies

Mapping Obscuration to Reionization with ALMA (MORA): 2 mm Efficiently Selects the Highest-redshift Obscured Galaxies

International audienceWe present the characteristics of 2 mm selected sources from the largest Atacama Large Millimeter/submillimeter Array (ALMA) blank-field contiguous survey conducted to date, the Mapping Obscuration to Reionization with ALMA (MORA) survey covering 184 arcmin2 at 2 mm. Twelve of 13 detections above 5σ are attributed to emission from galaxies, 11 of which are dominated by cold dust emission. These sources have a median redshift of $\langle {z}_{2\,\mathrm{mm}}\rangle ={3.6}_{-0.3}^{+0.4}$ primarily based on optical/near-infrared photometric redshifts with some spectroscopic redshifts, with 77% ± 11% of sources at z > 3 and 38% ± 12% of sources at z > 4. This implies that 2 mm selection is an efficient method for identifying the highest-redshift dusty star-forming galaxies (DSFGs). Lower-redshift DSFGs (z 3 yet are likely to drop out at 2 mm. MORA shows that DSFGs with star formation rates in excess of 300 M ⊙ yr-1 and a relative rarity of ~10-5 Mpc-3 contribute ~30% to the integrated star formation rate density at 3 2. Analysis of MORA sources' spectral energy distributions hint at steeper empirically measured dust emissivity indices than reported in typical literature studies, with $\langle \beta \rangle ={2.2}_{-0.4}^{+0.5}$ . The MORA survey represents an important step in taking census of obscured star formation in the universe's first few billion years, but larger area 2 mm surveys are needed to more fully characterize this rare population and push to the detection of the universe's first dusty galaxies

Hydroxychloroquine and tocilizumab therapy in COVID-19 patients—An observational study

Hydroxychloroquine has been touted as a potential COVID-19 treatment. Tocilizumab, an inhibitor of IL-6, has also been proposed as a treatment of critically ill patients. In this retrospective observational cohort study drawn from electronic health records we sought to describe the association between mortality and hydroxychloroquine or tocilizumab therapy among hospitalized COVID-19 patients. Patients were hospitalized at a 13-hospital network spanning New Jersey USA between March 1, 2020 and April 22, 2020 with positive polymerase chain reaction results for SARS-CoV-2. Follow up was through May 5, 2020. Among 2512 hospitalized patients with COVID-19 there have been 547 deaths (22%), 1539 (61%) discharges and 426 (17%) remain hospitalized. 1914 (76%) received at least one dose of hydroxychloroquine and 1473 (59%) received hydroxychloroquine with azithromycin. After adjusting for imbalances via propensity modeling, compared to receiving neither drug, there were no significant differences in associated mortality for patients receiving any hydroxychloroquine during the hospitalization (HR, 0.99 [95% CI, 0.80–1.22]), hydroxychloroquine alone (HR, 1.02 [95% CI, 0.83–1.27]), or hydroxychloroquine with azithromycin (HR, 0.98 [95% CI, 0.75–1.28]). The 30-day unadjusted mortality for patients receiving hydroxychloroquine alone, azithromycin alone, the combination or neither drug was 25%, 20%, 18%, and 20%, respectively. Among 547 evaluable ICU patients, including 134 receiving tocilizumab in the ICU, an exploratory analysis found a trend towards an improved survival association with tocilizumab treatment (adjusted HR, 0.76 [95% CI, 0.57–1.00]), with 30 day unadjusted mortality with and without tocilizumab of 46% versus 56%. This observational cohort study suggests hydroxychloroquine, either alone or in combination with azithromycin, was not associated with a survival benefit among hospitalized COVID-19 patients. Tocilizumab demonstrated a trend association towards reduced mortality among ICU patients. Our findings are limited to hospitalized patients and must be interpreted with caution while awaiting results of randomized trials