Nearby Type iii (galaxy-spanning) Kardashev supercivilizations would have high mid-infrared (MIR) luminosities. We have used the Wide-field Infrared Survey Explorer (WISE) to survey ∼ 1×10 5 galaxies for extreme MIR emission, 10 3 times more galaxies than the only previous such search. We have calibrated the WISE All-sky Catalog pipeline products to improve its photometry for extended sources. We present 563 extended sources with |b| ≥ 10 and red MIR colors, having visually vetted them to remove artifacts. No galaxies in our sample host an alien civilization reprocessing more than 85% of its starlight into the MIR, and only 50 galaxies, including Arp 220, have MIR luminosities consistent with > 50% reprocessing. Ninety of these (likely) extragalactic sources have little literature presence; in most cases they are likely barely resolved galaxies or pairs of galaxies undergoing large amounts of star formation. Five are new to science and deserve further study. The Be star 48 Librae sits within a MIR nebula, and we suggest that it may be creating dust. WISE, 2MASS, and Spitzer imagery shows that IRAS 04287+6444 is consistent with a previously unnoticed, heavily extinguished cluster of young stellar objects. We identify five "passive" (i.e. red) spiral galaxies with unusually high MIR and low NUV luminosity. We search a set of optically "dark" H I galaxies for MIR emission, and find none. These 90 poorly understood sources and five anomalous passive spirals deserve follow-up via both SETI and conventional astrophysics.
We present a novel infrared spectral energy distribution (SED) modeling methodology that uses likelihood-based weighting of the model fitting results to construct probabilistic H-R diagrams (pHRD) for X-ray identified, intermediate-mass (2-8 M ), pre-main sequence young stellar populations. This methodology is designed specifically for application to young stellar populations suffering strong, differential extinction (∆A V > 10 mag), typical of Galactic massive star-forming regions. We pilot this technique in the Carina Nebula Complex (CNC) by modeling the 1-8 µm SEDs of 2269 likely stellar members that exhibit no excess emission from circumstellar dust disks at 4.5 µm or shorter wavelengths. A subset of ∼100 intermediate-mass stars in the lightly-obscured Trumpler 14 and 16 clusters have available spectroscopic T eff , measured from the Gaia-ESO survey. We correctly identify the stellar temperature in 70% of cases, and the aggregate pHRD for all sources returns the same peak in the stellar age distribution as obtained using the spectroscopic T eff . The SED model parameter distributions of stellar mass and evolutionary age reveal significant variation in the duration of star formation among four large-scale stellar overdensities within the CNC and a large distributed stellar population. Star formation began ∼10 Myr ago and continues to the present day, with the star formation rate peaking 3 Myr ago when the massive Trumpler 14 and 16 clusters formed. We make public the set of 100,000 SED models generated from standard pre-main sequence evolutionary tracks and our custom software package for generating pHRDs and mass-age distributions from the SED fitting results.
ObjectivesGuidelines for testing individuals at risk (IAR) for developing pancreatic duct adenocarcinoma (PC) are being advanced from university hospital populations. We implemented a screen-in criteria and protocol for IAR for PC in our community hospital setting.MethodsEligibility was based on germline status and/or family history of PC. Longitudinal testing continued, alternating between endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI). The primary objective was to analyze pancreatic conditions and their associations with risk factors. The secondary objective was to evaluate the outcomes and complications resulting from testing.ResultsOver 93 months, 102 individuals completed baseline EUS, and 26 (25%) met defined endpoints of any abnormal findings in the pancreas. Average enrollment was 40 months, and all participants with endpoints continued standard surveillance. Two participants (1.8%) had endpoint findings requiring surgery for premalignant lesions. Increasing age predicted for endpoint findings. Analysis of longitudinal testing suggested reliability between the EUS and MRI results.ConclusionsIn our community hospital population, baseline EUS was effective in identifying the majority of findings; advancing age correlated with a greater chance of abnormalities. No differences were observed between EUS and MRI findings. Screening programs for PC among IAR can be successfully performed in the community setting.
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