2,736 research outputs found
The Extended Virgo Cluster Catalog
We present a new catalog of galaxies in the wider region of the Virgo
cluster, based on the Sloan Digital Sky Survey (SDSS) Data Release 7. The
Extended Virgo Cluster Catalog (EVCC) covers an area of 725 deg^2 or 60.1
Mpc^2. It is 5.2 times larger than the footprint of the classical Virgo Cluster
Catalog (VCC) and reaches out to 3.5 times the virial radius of the Virgo
cluster. We selected 1324 spectroscopically targeted galaxies with radial
velocities less than 3000 kms^-1. In addition, 265 galaxies that have been
missed in the SDSS spectroscopic survey but have available redshifts in the
NASA Extragalactic Database are also included. Our selection process secured a
total of 1589 galaxies of which 676 galaxies are not included in the VCC. The
certain and possible cluster members are defined by means of redshift
comparison with a cluster infall model. We employed two independent and
complementary galaxy classification schemes: the traditional morphological
classification based on the visual inspection of optical images and a
characterization of galaxies from their spectroscopic features. SDSS u, g, r,
i, and z passband photometry of all EVCC galaxies was performed using Source
Extractor. We compare the EVCC galaxies with the VCC in terms of morphology,
spatial distribution, and luminosity function. The EVCC defines a comprehensive
galaxy sample covering a wider range in galaxy density that is significantly
different from the inner region of the Virgo cluster. It will be the foundation
for forthcoming galaxy evolution studies in the extended Virgo cluster region,
complementing ongoing and planned Virgo cluster surveys at various wavelengths.Comment: 69 pages, 29 figures, 4 tables, accepted for publication in the ApJ
GaAs droplet quantum dots with nanometer-thin capping layer for plasmonic applications
We report on the growth and optical characterisation of droplet GaAs quantum
dots with extremely-thin (11 nm) capping layers. To achieve such result, an
internal thermal heating step is introduced during the growth and its role in
the morphological properties of the quantum dots obtained is investigated via
scanning electron and atomic force microscopy. Photoluminescence measurements
at cryogenic temperatures show optically stable, sharp and bright emission from
single quantum dots, at near-infrared wavelengths. Given the quality of their
optical properties and the proximity to the surface, such emitters are ideal
candidates for the investigation of near field effects, like the coupling to
plasmonic modes, in order to strongly control the directionality of the
emission and/or the spontaneous emission rate, crucial parameters for quantum
photonic applications.Comment: 1 pages, 3 figure
Calibration of Built-in Accelerometer Using a Commercially Available Smartphone
Wearable trackers that detect sleep offer users a way to track their sleep quality and patterns without the use of expensive equipment. Few studies have tested the validity of these trackers on sleep measure. PURPOSE: To examine the validity of the Actigraph GT9X (AG), SenseWear Mini Armband (SW), Basis Peak (BP), Fitbit Charge HR (FB), Jawbone UP3 (JU), and Garmin Vivosmart (GV) for estimating sleep variables as compared with a sleep diary. METHODS: 78 healthy individuals participated in the study. Group 1 (n= 38) and wore the AG, SW, BP, and FB or Group 2 (n = 40) and wore the AG, JU, and GV. Monitors were worn on the non-dominant arm for 3 nights and a sleep log was completed. Sleep variables were total sleep time (TST), time in bed (TIB), sleep efficiency (SE), and wake after sleep onset (WASO). Pearson correlation, mean absolute percentage errors (MAPE), equivalence testing, Bland-Altman plots, and ANOVA were used to assess validity compared with the diary. RESULTS: Overall, monitors that showed the greatest correlation with the sleep diary for TST were the JU and FB (effect size= 0.09 and 0.23, respectively). The greatest correlation with the sleep diary for TIB was seen with the SW, GV, and JU (effect size= 0.09, 0.16, and 0.07, respectively). SE and WASO showed very poor correlation with the log. Measures for equivalence testing confirmed the success of the JU, SW, FB, and GV for measureing TIB and TST. CONCLUSION: The FB, SW, JU, and GV could be valid measure of TST and TIB. The monitors are not valid regarding wake times during sleep. Further research is needed to validate these monitors with polysomnography
Genetic reduction of lipoic acid synthase expression modestly increases atherosclerosis in male, but not in female, apolipoprotein E-deficient mice
To evaluate the effects of a genetic reduction of Lias gene expression on atherosclerosis development
Electric field control of nonvolatile four-state magnetization at room temperature
We find the realization of large converse magnetoelectric (ME) effects at
room temperature in a multiferroic hexaferrite
BaSrCoFeO single crystal, in which rapid
change of electric polarization in low magnetic fields (about 5 mT) is coined
to a large ME susceptibility of 3200 ps/m. The modulation of magnetization then
reaches up to 0.62 /f.u. in an electric field of 1.14 MV/m. We find
further that four ME states induced by different ME poling exhibit unique,
nonvolatile magnetization versus electric field curves, which can be
approximately described by an effective free energy with a distinct set of ME
coefficients
Light-chain amyloidosis presenting with rapidly progressive submucosal hemorrhage of the stomach
SummaryThe gastrointestinal tract is frequently in involved light-chain (AL) amyloidosis, but significant hemorrhagic complications are rare. A 71-year-old man presented to our hospital with dyspepsia and heartburn for 1 month. Gastroscopy revealed a large submucosal hematoma at the gastric fundus. Two days later, a follow-up gastroscopy indicated extensive expansion of the hematoma throughout the upper half of the stomach. The hematoma displayed ongoing expansion during the endoscopic examination, suggesting that rupture was imminent. Emergency total gastrectomy was performed, and amyloidosis was confirmed after examining the surgical specimen. Bone marrow examination revealed multiple myeloma, and serum immunoglobulin assay confirmed the diagnosis of myeloma-associated AL amyloidosis. At manuscript submission, the patient was doing well and was undergoing chemotherapy
Multi-institution analysis of racial disparity among African- American men eligible for prostate cancer active surveillance
There is a significant controversy on whether race should be a factor in considering active surveillance for low-risk prostate cancer. To address this question, we analyzed a multi-institution database to assess racial disparity between African-American and White-American men with low risk prostate cancer who were eligible for active surveillance but underwent radical prostatectomy. A retrospective analysis of prospectively collected clinical, pathologic and oncologic outcomes of men with low-risk prostate cancer from seven tertiary care institutions that underwent radical prostatectomy from 2003–2014 were used to assess potential racial disparity. Of the 333 (14.8%) African-American and 1923 (85.2%) White-American men meeting active surveillance criteria, African-American men were found to be slightly younger (57.5 vs 58.5 years old; p = 0.01) and have higher BMI (29.3 v 27.9; p \u3c 0.01), pre-op PSA (5.2 v 4.7; p \u3c 0.01), and maximum percentage cancer on biopsy (15.1% v 13.6%; p \u3c 0.01) compared to White-American men. Univariate and multivariate analysis demonstrated similar rates of upgrading, upstaging, positive surgical margin, and biochemical recurrence between races. These results suggest that single institution studies recommending more stringent AS enrollment criteria for AA men with a low-risk prostate cancer may not capture the complete oncologic landscape due to institutional variability in cancer outcomes. Since all seven institutions demonstrated no significant racial disparity, current active surveillance eligibility should not be modified based upon race until a prospective study has been completed. © Dinizo et al
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