13 research outputs found
The AllWISE Motion Survey, Part 2
We use the AllWISE Data Release to continue our search for WISE-detected
motions. In this paper, we publish another 27,846 motion objects, bringing the
total number to 48,000 when objects found during our original AllWISE motion
survey are included. We use this list, along with the lists of confirmed
WISE-based motion objects from the recent papers by Luhman and by Schneider et
al. and candidate motion objects from the recent paper by Gagne et al. to
search for widely separated, common-proper-motion systems. We identify 1,039
such candidate systems. All 48,000 objects are further analyzed using
color-color and color-mag plots to provide possible characterizations prior to
spectroscopic follow-up. We present spectra of 172 of these, supplemented with
new spectra of 23 comparison objects from the literature, and provide
classifications and physical interpretations of interesting sources. Highlights
include: (1) the identification of three G/K dwarfs that can be used as
standard candles to study clumpiness and grain size in nearby molecular clouds
because these objects are currently moving behind the clouds, (2) the
confirmation/discovery of several M, L, and T dwarfs and one white dwarf whose
spectrophotometric distance estimates place them 5-20 pc from the Sun, (3) the
suggestion that the Na 'D' line be used as a diagnostic tool for interpreting
and classifying metal-poor late-M and L dwarfs, (4) the recognition of a triple
system including a carbon dwarf and late-M subdwarf, for which model fits of
the late-M subdwarf (giving [Fe/H] ~ -1.0) provide a measured metallicity for
the carbon star, and (5) a possible 24-pc-distant K5 dwarf + peculiar red L5
system with an apparent physical separation of 0.1 pc.Comment: 62 pages with 80 figures, accepted for publication in The
Astrophysical Journal Supplement Series, 23 Mar 2016; second version fixes a
few small typos and corrects the footnotes for Table
The AllWISE Motion Survey and the Quest for Cold Subdwarfs
The AllWISE processing pipeline has measured motions for all objects detected on Wide-field Infrared Survey Explorer (WISE) images taken between 2010 January and 2011 February. In this paper, we discuss new capabilities made to the software pipeline in order to make motion measurements possible, and we characterize the resulting data products for use by future researchers. Using a stringent set of selection criteria, we find 22,445 objects that have significant AllWISE motions, of which 3525 have motions that can be independently confirmed from earlier Two Micron All Sky Survey (2MASS) images, yet lack any published motions in SIMBAD. Another 58 sources lack 2MASS counterparts and are presented as motion candidates only. Limited spectroscopic follow-up of this list has already revealed eight new L subdwarfs. These may provide the first hints of a "subdwarf gap" at mid-L types that would indicate the break between the stellar and substellar populations at low metallicities (i.e., old ages). Another object in the motion list—WISEA J154045.67–510139.3—is a bright (J ≈ 9 mag) object of type M6; both the spectrophotometric distance and a crude preliminary parallax place it ~6 pc from the Sun. We also compare our list of motion objects to the recently published list of 762 WISE motion objects from Luhman. While these first large motion studies with WISE data have been very successful in revealing previously overlooked nearby dwarfs, both studies missed objects that the other found, demonstrating that many other nearby objects likely await discovery in the AllWISE data products
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COVID-19: Review of a 21st Century Pandemic from Etiology to Neuro-psychiatric Implications.
COVID-19 is a severe infectious disease that has claimed >150,000 lives and infected millions in the United States thus far, especially the elderly population. Emerging evidence has shown the virus to cause hemorrhagic and immunologic responses, which impact all organs, including lungs, kidneys, and the brain, as well as extremities. SARS-CoV-2 also affects patients', families', and society's mental health at large. There is growing evidence of re-infection in some patients. The goal of this paper is to provide a comprehensive review of SARS-CoV-2-induced disease, its mechanism of infection, diagnostics, therapeutics, and treatment strategies, while also focusing on less attended aspects by previous studies, including nutritional support, psychological, and rehabilitation of the pandemic and its management. We performed a systematic review of >1,000 articles and included 425 references from online databases, including, PubMed, Google Scholar, and California Baptist University's library. COVID-19 patients go through acute respiratory distress syndrome, cytokine storm, acute hypercoagulable state, and autonomic dysfunction, which must be managed by a multidisciplinary team including nursing, nutrition, and rehabilitation. The elderly population and those who are suffering from Alzheimer's disease and dementia related illnesses seem to be at the higher risk. There are 28 vaccines under development, and new treatment strategies/protocols are being investigated. The future management for COVID-19 should include B-cell and T-cell immunotherapy in combination with emerging prophylaxis. The mental health and illness aspect of COVID-19 are among the most important side effects of this pandemic which requires a national plan for prevention, diagnosis and treatment