932 research outputs found

    Evidence of boosted 13CO/12CO ratio in early-type galaxies in dense environments

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    We present observations of 13^{13}CO(1-0) in 17 Combined Array for Research in Millimeter Astronomy (CARMA) Atlas3D early-type galaxies (ETGs), obtained simultaneously with 12^{12}CO(1-0) observations. The 13^{13}CO in six ETGs is sufficiently bright to create images. In these 6 sources, we do not detect any significant radial gradient in the 13^{13}CO/12^{12}CO ratio between the nucleus and the outlying molecular gas. Using the 12^{12}CO channel maps as 3D masks to stack the 13^{13}CO emission, we are able to detect 15/17 galaxies to >3σ>3\sigma (and 12/17 to at least 5σ\sigma) significance in a spatially integrated manner. Overall, ETGs show a wide distribution of 13^{13}CO/12^{12}CO ratios, but Virgo cluster and group galaxies preferentially show a 13^{13}CO/12^{12}CO ratio about 2 times larger than field galaxies, although this could also be due to a mass dependence, or the CO spatial extent (RCO/ReR_{\rm CO}/R_{\rm e}). ETGs whose gas has a morphologically-settled appearance also show boosted 13^{13}CO/12^{12}CO ratios. We hypothesize that this variation could be caused by (i) the extra enrichment of gas from molecular reprocessing occurring in low-mass stars (boosting the abundance of 13^{13}C to 12^{12}C in the absence of external gas accretion), (ii) much higher pressure being exerted on the midplane gas (by the intracluster medium) in the cluster environment than in isolated galaxies, or (iii) all but the densest molecular gas clumps being stripped as the galaxies fall into the cluster. Further observations of 13^{13}CO in dense environments, particularly of spirals, as well as studies of other isotopologues, should be able to distinguish between these hypotheses.Comment: 13 pages, 3 tables, 7 figures, accepted by MNRA

    Surface wave control for large arrays of microwave kinetic inductance detectors

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    Large ultra-sensitive detector arrays are needed for present and future observatories for far infra-red, submillimeter wave (THz), and millimeter wave astronomy. With increasing array size, it is increasingly important to control stray radiation inside the detector chips themselves, the surface wave. We demonstrate this effect with focal plane arrays of 880 lens-antenna coupled Microwave Kinetic Inductance Detectors (MKIDs). Presented here are near field measurements of the MKID optical response versus the position on the array of a reimaged optical source. We demonstrate that the optical response of a detector in these arrays saturates off-pixel at the 30\sim-30 dB level compared to the peak pixel response. The result is that the power detected from a point source at the pixel position is almost identical to the stray response integrated over the chip area. With such a contribution, it would be impossible to measure extended sources, while the point source sensitivity is degraded due to an increase of the stray loading. However, we show that by incorporating an on-chip stray light absorber, the surface wave contribution is reduced by a factor >>10. With the on-chip stray light absorber the point source response is close to simulations down to the 35\sim-35 dB level, the simulation based on an ideal Gaussian illumination of the optics. In addition, as a crosscheck we show that the extended source response of a single pixel in the array with the absorbing grid is in agreement with the integral of the point source measurements.Comment: accepted for publication in IEEE Transactions on Terahertz Science and Technolog

    HIV infection is associated with elevated biomarkers of immune activation in Ugandan adults with pneumonia.

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    IntroductionPneumonia is an important cause of morbidity and mortality in persons living with human immunodeficiency virus (HIV) infection. How immune activation differs among HIV-infected and HIV-uninfected adults with pneumonia is unknown.MethodsThe Inflammation, Aging, Microbes, and Obstructive Lung Disease (I AM OLD) Cohort is a prospective cohort of adults with pneumonia in Uganda. In this cross-sectional analysis, plasma was collected at pneumonia presentation to measure the following 12 biomarkers: interleukin 6 (IL-6), soluble tumor necrosis factor receptors 1 and 2 (sTNFR-1 and sTNFR-2), high sensitivity C-reactive protein (hsCRP), fibrinogen, D-dimer, soluble CD27 (sCD27), interferon gamma-inducible protein 10 (IP-10), soluble CD14 (sCD14), soluble CD163 (sCD163), hyaluronan, and intestinal fatty acid binding protein. We asked whether biomarker levels differed between HIV-infected and HIV-uninfected participants, and whether higher levels of these biomarkers were associated with mortality.ResultsOne hundred seventy-three participants were enrolled. Fifty-three percent were HIV-infected. Eight plasma biomarkers-sTNFR-1, sTNFR-2, hsCRP, D-dimer, sCD27, IP-10, sCD14, and hyaluronan-were higher among participants with HIV infection, after adjustment for pneumonia severity. Higher levels of 8 biomarkers-IL-6, sTNFR-1, sTNFR-2, hsCRP, IP-10, sCD14, sCD163, and hyaluronan-were associated with increased 2-month mortality.ConclusionsAs in other clinical contexts, HIV infection is associated with a greater degree of immune activation among Ugandan adults with pneumonia. Some of these are also associated with short-term mortality. Further study is needed to explore whether these biomarkers might predict poor long-term outcomes-such as the development of obstructive lung disease-in patients with HIV who have recovered from pneumonia

    Deterioation

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    Star Formation in Nearby Early-Type Galaxies: The Radio Continuum Perspective

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    We present a 1.4 GHz Karl G. Jansky Very Large Array (VLA) study of a sample of early-type galaxies (ETGs) from the volume- and magnitude-limited ATLAS-3D survey. The radio morphologies of these ETGs at a resolution of 5" are diverse and include sources that are compact on sub-kpc scales, resolved structures similar to those seen in star-forming spiral galaxies, and kpc-scale radio jets/lobes associated with active nuclei. We compare the 1.4 GHz, molecular gas, and infrared (IR) properties of these ETGs. The most CO-rich ATLAS-3D ETGs have radio luminosities consistent with extrapolations from H_2-mass-derived star formation rates from studies of late-type galaxies. These ETGs also follow the radio-IR correlation. However, ETGs with lower molecular gas masses tend to have less radio emission relative to their CO and IR emission compared to spirals. The fraction of galaxies in our sample with high IR-radio ratios is much higher than in previous studies, and cannot be explained by a systematic underestimation of the radio luminosity due to the presence extended, low-surface-brightness emission that was resolved-out in our VLA observations. In addition, we find that the high IR-radio ratios tend to occur at low IR luminosities, but are not associated with low dynamical mass or metallicity. Thus, we have identified a population of ETGs that have a genuine shortfall of radio emission relative to both their IR and molecular gas emission. A number of mechanisms may conspire to cause this radio deficiency, including a bottom-heavy stellar initial mass function, weak magnetic fields, a higher prevalence of environmental effects compared to spirals and enhanced cosmic ray losses.Comment: accepted for publication in MNRA

    Chechnya: Reconstruction Amidst the War

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    In 2003 the need for mine action assistance in the northern Caucasus remains formidable. By furthering mine awareness, survivor assistance and data collection, organizations such as the United Nations Children’s Fund (UNICEF) and the International Committee of the Red Cross (ICRC) are helping the people of Chechnya do what they can to survive during times of war

    Victimization and Health Experiences for TGNC Individuals in Women\u27s Prisons

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    This text examines the health-related experiences of transgender and gender nonconforming persons assigned female at birth within the criminal justice system. It moves through a transgender-centric approach to explore the ways gender nonconformity relates to experiences of violence and healthcare disparities for those interacting with law enforcement and incarcerated in women\u27s prisons. The study utilized statistical analyses of nationally representative data in the 2015 U.S. Transgender Survey carried out by the National Center for Transgender Equality. Multivariate analyses suggested significant connections between race and education and experiences of harassment and assault within the criminal justice context. There were largely mixed results regarding the direct connections between gender conformity and transition status and experiences of violence. These findings provide initial exploratory quantitative data for the realities of transmasculine and nonbinary persons assigned female at birth within the criminal justice system and provide starting points for future research
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