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Discovery of a transient ultraluminous X-ray source in the elliptical galaxy M86
No full textWe report the discovery of the transient ultraluminous X-ray source (ULX) CXOU J122602.3+125951 (hereafter M86 tULX-1), located 3′52″ (19 kpc) north-west of the centre of the giant elliptical galaxy M86 (NGC 4406) in the Virgo Cluster. The spectrum of M86 tULX-1 can be fit by a power law plus multicolour disc model with a 1.0 index and a 0.66 keV inner disc temperature, or by a power law with a 1.86 ± 0.10 index. For an isotropically emitting source at the distance of M86, the luminosity based on the superposition of spectral models is (5 ± 1) × 10 erg s. Its relatively hard spectrum places M86 tULX-1 in a hitherto unpopulated region in the luminosity-disc temperature diagram, between other ULXs and the (sub-Eddington) black-hole X-ray binaries. We discovered M86 tULX-1 in an archival 148-ks 2013 July Chandra observation, and it was not detected in a 20-ks 2016 May Chandra observation, meaning it faded by a factor of at least 30 in three years. Based on our analysis of deep optical imaging of M86, it is probably not located in a globular cluster. It is the brightest ULX found in an old field environment unaffected by recent galaxy interaction. We conclude that M86 tULX-1 may be a stellar-mass black hole of ∼30–100 M⊙ with a low-mass giant companion, or a transitional object in a state between the normal stellar-mass black holes and the ultraluminous state
Personal exposure to polycyclic aromatic hydrocarbons in Appalachian mining communities
No full textCoal mining activities may increase residential exposure to polycyclic aromatic hydrocarbons (PAHs), but personal PAH exposures have not been studied in mining areas. We used silicone wristbands as passive personal samplers to estimate PAH exposures in coal mining communities in Central Appalachia in the United States. Adults (N = 101) wore wristbands for one week; 51 resided in communities within approximately three miles of surface mining sites, and 50 resided 10 or more miles from mining sites. Passive indoor polyurethane foam (PUF) sampling was conducted in residents’ homes, and a sample of 16 outdoor PUF samples were also collected. Nine PAH congeners were commonly detected in wristbands (mean ± standard deviation), including phenanthrene (50.2 ± 68.7 ng/g), benz[a]anthracene (20.2 ± 58.2 ng/g), fluoranthene (19.4 ± 24.1 ng/g) and pyrene (15.2 ± 18.2 ng/g). Controlling for participant characteristics and season, participants living closer to mining sites had significantly higher levels of phenanthrene, fluorene, fluoranthene, pyrene and ∑PAHs in wristbands compared to participants living farther from mining. Indoor air showed no significant group differences except for pyrene, but outdoor air showed significant or marginally significant differences for phenanthrene, fluorene, pyrene and ∑PAHs. The results suggest that mining community residents face exposure to outdoor mining-related pollutants, and demonstrate that personal silicone wristbands can be deployed as effective passive sampling devices
A = 0 Multiwavelength Galaxy Synthesis. I. A WISE and GALEX Atlas of Local Galaxies
No full textWe present an atlas of ultraviolet and infrared images of ~15,750 local (d 100,000 galaxies, these calibrations have high precision and allow us to rigorously compare local galaxies to Sloan Digital Sky Survey results. We provide these SFR and M estimates for all galaxies in our sample and show that our results yield a "main sequence" of star forming galaxies comparable to previous work. We also show the distribution of intensities from resolved galaxies in NUV-to-WISE1 vs. WISE1-to-WISE3 space, which captures much of the key physics accessed by these bands
Dignity and Social Meaning: Obergefell, Windsor, and Lawrence as Constitutional Dialogue
No full textThe U.S. Supreme Court’s three most important gay and lesbian rights decisions—Obergefell v. Hodges, United States v. Windsor, and Lawrence v. Texas—are united by the principle that gays and lesbians are entitled to dignity. Beyond their tangible consequences, the common constitutional evil of state bans on same-sex marriage, the federal Defense of Marriage Act, and sodomy laws was that they imposed dignitary harm. This Article explores how the gay and lesbian dignity cases exemplify the process by which constitutional law emerges from a social and cultural dialogue in which the Supreme Court actively participates. In doing so, it draws on the scholarly literatures on dialogic judicial review and the role of social meaning in constitutional law. It illuminates how the Supreme Court interprets democratic preferences and constructs social meaning in order to apply fundamental constitutional norms to emerging legal claims. Contrary to the speculations of some commentators, “dignity” in these cases did not operate as some new form of constitutional right. Rather, the identification and protection of dignitary interests served as the unifying principle for a process, unfolding in three cases over thirteen years, through which constitutional law was brought into alignment with evolving public attitudes and policy preferences. The dignity decisions should be understood as majoritarian, not as acts of judicial will. They were broadly accepted because the Court’s insights about the status of gays and lesbians in American society were consistent with dramatic and long-term changes in cultural and public attitudes. As culture and attitudes evolved, so did the social meaning of anti-gay laws. Sodomy laws and marriage restrictions, once accepted as presumptively constitutional protections of tradition and public morality, increasingly came to be understood as impositions of stigma and humiliation—the kind of expressive harms that the U.S. Constitution forbids
Quantifying association between liver tumor incidence and early-stage liver weight increase - An NTP data analysis
No full textTwo-year toxicology and carcinogenesis rodent studies conducted at the National Toxicology Program (NTP) are used to identify potential adverse health effects in humans due to chemical exposure, including cancer. Liver tumor, the most frequently diagnosed tumor type of chemically induced neoplastic effects documented in NTP’s carcinogenicity studies, is usually difficult to be detected at early stage due to the inconspicuous symptoms. However, the abnormal growth of liver cells can lead to liver weight increase, so it is hypothesized that liver tumor incidence is associated with early stage liver weight increase. In this study, the association between liver weight increase and liver tumor incidence are quantified by (1) calculating the correlation coefficient of and (2) building quantitative linear relationship between benchmark dose estimates derived from these two types of data collected from NTP studies. Together with 151 chemical/species/sex combinations of liver tumor data showing positive evidence collected from 76 NTP long-term studies, short-term liver weight data reported in the same NTP report were extracted to be paired with the liver tumor data for the analyses. Results show that the estimated correlation coefficients (as high as 0.78) along with the adequately fitted linear models suggest that the association between relative liver weight increase and aggregated liver tumor incidence are relatively strong. Additional analyses focused on some more specific situations (e.g., specific tumor type or specific strain/sex combination) further confirmed the strong association. Given the design of this study, the interpretation of the findings is not that liver weight increase can be used to predict liver tumor incidence, instead, evident increase in liver weight might be used as a reason to prioritize the test article for a two-year toxicology and carcinogenesis study
How Older Adults Cope with Cognitive Complexity and Environmental Constraints during Dual-Task Walking: The Role of Executive Function Involvement
No full textThis cross-sectional study investigated the interactive dual-task (DT) effects of executive function demands and environmental constraints on older adults’ walking and the moderating role of habitual physical activity (PA). Locomotor performance under different environmental constraints (flat versus obstructed walking) and cognitive performance with different executive function involvement (backward counting versus random number generation) were assessed under single-task (ST) and DT conditions in 135 participants (mean age 68.1 ± 8.4). The weekly number of daily steps was measured. Reciprocal DT effects of walking on cognitive performance and of the cognitive task on gait performance were computed and submitted to analyses of covariance with age, PA level, and cognitive functioning as covariates, followed by linear regressions with PA level as predictor. Cognitive task demands and environmental constraints individually and jointly affected gait variability (p = 0.033, = 0.08) and executive function performance (p = 0.009, = 0.09). Physical activity level predicted a low but significant percentage of variance of DT effects on gait only in flat walking (R = 0.04, p = 0.027). Results suggest that older individuals may adopt variable task prioritization in dual tasking depending on the type of executive function involvement and the environmental constraints on walking. Their DT ability was slightly affected by habitual P
Review and analysis of grading scales for ocular surface staining
No full textVital dye staining has been used for over a century to assess the severity of ocular surface disease. However, despite common usage, a universally accepted “gold standard” grading scale does not exist for corneal and conjunctival staining, which can impact the ability to diagnose and monitor ocular surface conditions such as dry eye. The Food and Drug Administration (FDA) and other international regulatory agencies rely on ocular surface staining as a primary endpoint for new drug approvals, so that absence of a “gold standard” scale may affect approval of new drug treatments. To begin to address this problem, we review existing, published grading scales in an integrated fashion, highlighting their differences and similarities to emphasize common themes and the methods and elements that are important in creating a standardized scale. Our goal is to aid the field in moving towards an accepted standardized grading scale for ocular surface staining that can be applied in clinic and research settings for a variety of ocular conditions
A New Cryogenic Apparatus to Search for the Neutron Electric Dipole Moment
No full textA cryogenic apparatus is described that enables a new experiment, nEDM@SNS, with a major improvement in sensitivity compared to the existing limit in the search for a neutron Electric Dipole Moment (EDM). This apparatus uses superfluid He to produce a high density of Ultra-Cold Neutrons (UCN) which are contained in a suitably coated pair of measurement cells. The experiment, to be operated at the Spallation Neutron Source at Oak Ridge National Laboratory, uses polarized He from an Atomic Beam Source injected into the superfluid He and transported to the measurement cells where it serves as a co-magnetometer. The superfluid He is also used as an insulating medium allowing significantly higher electric fields, compared to previous experiments, to be maintained across the measurement cells. These features provide an ultimate statistical uncertainty for the EDM of 2−3× 10 e-cm, with anticipated systematic uncertainties below this level
Macroscale intrinsic network architecture of the hypothalamus
No full textControl of multiple life-critical physiological and behavioral functions requires the hypothalamus. Here, we provide a comprehensive description and rigorous analysis of mammalian intrahypothalamic network architecture. To achieve this at the gray matter region (macroscale) level, macroscale connection (macroconnection) data for the rat hypothalamus were extracted from the primary literature. The dataset indicated the existence of 7,982 (of 16,770 possible) intrahypothalamic macroconnections. Network analysis revealed that the intrahypothalamic macroconnection network (its macroscale subconnectome) is divided into two identical top-level subsystems (or subnetworks), each composed of two nested second-level subsystems. At the top-level, this suggests a deeply integrated network; however, regional grouping of the two second-level subsystems suggested a partial separation between control of physiological functions and behavioral functions. Furthermore, inclusion of four candidate hubs (dominant network nodes) in the second-level subsystem that is associated prominently with physiological control suggests network primacy with respect to this function. In addition, comparison of network analysis with expression of gene markers associated with inhibitory (GAD65) and excitatory (VGLUT2) neurotransmission revealed a significant positive correlation between measures of network centrality (dominance) and the inhibitory marker. We discuss these results in relation to previous understandings of hypothalamic organization and provide, and selectively interrogate, an updated hypothalamus structure–function network model to encourage future hypothesis-driven investigations of identified hypothalamic subsystems
Determination of the Pole Position of the Lightest Hybrid Meson Candidate
No full textMapping states with explicit gluonic degrees of freedom in the light sector is a challenge, and has led to controversies in the past. In particular, the experiments have reported two different hybrid candidates with spin-exotic signature, ( 1400 ) and ( 1600 ) , which couple separately to and . This picture is not compatible with recent Lattice QCD estimates for hybrid states, nor with most phenomenological models. We consider the recent partial wave analysis of the system by the COMPASS Collaboration. We fit the extracted intensities and phases with a coupled-channel amplitude that enforces the unitarity and analyticity of the S matrix. We provide a robust extraction of a single exotic resonant pole, with mass and width 1564 ± 24 ± 86 and 492 ± 54 ± 102 MeV , which couples to both channels. We find no evidence for a second exotic state. We also provide the resonance parameters of the ( 1320 ) and ( 1700 )