96 research outputs found
The use of admissions simulation to stabilize ancillary workloads
As part of the planning of a new hospital, an analysis was per formed to determine the number of procedures that would be performed in each of nineteen ancillary departments on a day of the week basis. Because the planned occupancy was not the maximum possible, attempts were made using simulation to smooth the daily ancillary loads by varying the admission day of elective, urgent inpatient and outpatient loads. The methodology, sample outputs, and main conclusions are presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69095/2/10.1177_003754978404300203.pd
Ascomycetous yeast species recovered from grapes damaged by honeydew and sour rot
Aims: To identify ascomycetous yeasts recovered from sound and damaged
grapes by the presence of honeydew or sour rot.
Methods and Results: In sound grapes, the mean yeast counts ranged from
3.20 ± 1.04 log CFU g-1 to 5.87 ± 0.64 log CFU g-1. In honeydew grapes, the
mean counts ranged from 3.88 ± 0.80 log CFU g-1 to 6.64 ± 0.77 log CFU g-1.
In sour rot grapes counts varied between 6.34 ± 1.03 and 7.68 ± 0.38 log
CFU g-1. Hanseniaspora uvarum was the most frequent species from sound
samples. In both types of damage, the most frequent species were Candida vanderwaltii,
H. uvarum and Zygoascus hellenicus. The latter species was recovered
in high frequency because of the utilization of the selective medium DBDM
(Dekkera â Brettanomyces differential medium). The scarce isolation frequency of
the wine spoilage species Zygosaccharomyces bailii (in sour rotten grapes) and
Zygosaccharomyces bisporus (in honeydew affected grapes) could only be
demonstrated by the use of the selective medium ZDM (Zygosaccharomyces
differential medium).
Conclusions: The isolation of several species only from damaged grapes indicates
that damage constituted the main factor determining yeast diversity. The
utilization of selective media is required for eliciting the recovery of potentially
wine spoilage species.
Significance and Impact of the Study: The impact of damaged grapes in the yeast ecology of grapes has been underestimate
Measuring Black Hole Spin using X-ray Reflection Spectroscopy
I review the current status of X-ray reflection (a.k.a. broad iron line)
based black hole spin measurements. This is a powerful technique that allows us
to measure robust black hole spins across the mass range, from the stellar-mass
black holes in X-ray binaries to the supermassive black holes in active
galactic nuclei. After describing the basic assumptions of this approach, I lay
out the detailed methodology focusing on "best practices" that have been found
necessary to obtain robust results. Reflecting my own biases, this review is
slanted towards a discussion of supermassive black hole (SMBH) spin in active
galactic nuclei (AGN). Pulling together all of the available XMM-Newton and
Suzaku results from the literature that satisfy objective quality control
criteria, it is clear that a large fraction of SMBHs are rapidly-spinning,
although there are tentative hints of a more slowly spinning population at high
(M>5*10^7Msun) and low (M<2*10^6Msun) mass. I also engage in a brief review of
the spins of stellar-mass black holes in X-ray binaries. In general,
reflection-based and continuum-fitting based spin measures are in agreement,
although there remain two objects (GROJ1655-40 and 4U1543-475) for which that
is not true. I end this review by discussing the exciting frontier of
relativistic reverberation, particularly the discovery of broad iron line
reverberation in XMM-Newton data for the Seyfert galaxies NGC4151, NGC7314 and
MCG-5-23-16. As well as confirming the basic paradigm of relativistic disk
reflection, this detection of reverberation demonstrates that future large-area
X-ray observatories such as LOFT will make tremendous progress in studies of
strong gravity using relativistic reverberation in AGN.Comment: 19 pages. To appear in proceedings of the ISSI-Bern workshop on "The
Physics of Accretion onto Black Holes" (8-12 Oct 2012). Revised version adds
a missing source to Table 1 and Fig.6 (IRAS13224-3809) and corrects the
referencing of the discovery of soft lags in 1H0707-495 (which were in fact
first reported in Fabian et al. 2009
Anatomy of the AGN in NGC 5548. II. The spatial, temporal, and physical nature of the outflow from HST/COS Observations
Anatomy of the AGN in NGC 5548. II. The spatial, temporal, and physical nature of the outflow from HST/COS Observations
Anatomy of the AGN in NGC 5548. VIII. XMM-Newton's EPIC detailed view of an unexpected variable multilayer absorber
Galaxie
Spi-OPS : Spitzer and CHEOPS confirm the near-polar orbit of MASCARA-1 b and reveal a hint of dayside reflection
A.C.C. and T.G.W. acknowledge support from STFC consolidated grant number ST/M001296/1.Context. The light curves of tidally locked hot Jupiters transiting fast-rotating, early-type stars are a rich source of information about both the planet and star, with full-phase coverage enabling a detailed atmospheric characterisation of the planet. Although it is possible to determine the true spinâorbit angle Κ â a notoriously difficult parameter to measure â from any transit asymmetry resulting from gravity darkening induced by the stellar rotation, the correlations that exist between the transit parameters have led to large disagreements in published values of Κ for some systems. Aims. We aimed to study these phenomena in the light curves of the ultra-hot Jupiter MASCARA-1 b, which is characteristically similar to well-studied contemporaries such as KELT-9 b and WASP-33 b. Methods. We obtained optical CHaracterising ExOPlanet Satellite (CHEOPS) transit and occultation light curves of MASCARA-1 b, and analysed them jointly with a Spitzer/IRAC 4.5 ÎŒm full-phase curve to model the asymmetric transits, occultations, and phase-dependent flux modulation. For the latter, we employed a novel physics-driven approach to jointly fit the phase modulation by generating a single 2D temperature map and integrating it over the two bandpasses as a function of phase to account for the differing planetâstar flux contrasts. The reflected light component was modelled using the general ab initio solution for a semi-infinite atmosphere. Results. When fitting the CHEOPS and Spitzer transits together, the degeneracies are greatly diminished and return results consistent with previously published Doppler tomography. Placing priors informed by the tomography achieves even better precision, allowing a determination of Κ = 72.1â2.4+2.5 deg. From the occultations and phase variations, we derived dayside and nightside temperatures of 3062â68+66 K and 1720 ± 330 K, respectively.Our retrieval suggests that the dayside emission spectrum closely follows that of a blackbody. As the CHEOPS occultation is too deep to be attributed to blackbody flux alone, we could separately derive geometric albedo Ag = 0.171â0.068+0.066 and spherical albedo As = 0.266â0.100+0.097 from the CHEOPS data, and Bond albedoAB = 0.057â0.101+0.083 from the Spitzer phase curve.Although small, the Ag and As indicate that MASCARA-1 b is more reflective than most other ultra-hot Jupiters, where Hâ absorption is expected to dominate. Conclusions. Where possible, priors informed by Doppler tomography should be used when fitting transits of fast-rotating stars, though multi-colour photometry may also unlock an accurate measurement of Κ. Our approach to modelling the phase variations at different wavelengths provides a template for how to separate thermal emission from reflected light in spectrally resolved James Webb Space Telescope phase curve data.Publisher PDFPeer reviewe
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Gaia Early Data Release 3: Gaia photometric science alerts
Context. Since July 2014, the Gaia mission has been engaged in a high-spatial-resolution, time-resolved, precise, accurate astrometric, and photometric survey of the entire sky. Aims. We present the Gaia Science Alerts project, which has been in operation since 1 June 2016. We describe the system which has been developed to enable the discovery and publication of transient photometric events as seen by Gaia. Methods. We outline the data handling, timings, and performances, and we describe the transient detection algorithms and filtering procedures needed to manage the high false alarm rate. We identify two classes of events: (1) sources which are new to Gaia and (2) Gaia sources which have undergone a significant brightening or fading. Validation of the Gaia transit astrometry and photometry was performed, followed by testing of the source environment to minimise contamination from Solar System objects, bright stars, and fainter near-neighbours. Results. We show that the Gaia Science Alerts project suffers from very low contamination, that is there are very few false-positives. We find that the external completeness for supernovae, CE = 0.46, is dominated by the Gaia scanning law and the requirement of detections from both fields-of-view. Where we have two or more scans the internal completeness is CI = 0.79 at 3 arcsec or larger from the centres of galaxies, but it drops closer in, especially within 1 arcsec. Conclusions. The per-Transit photometry for Gaia transients is precise to 1% at G = 13, and 3% at G = 19. The per-Transit astrometry is accurate to 55 mas when compared to Gaia DR2. The Gaia Science Alerts project is one of the most homogeneous and productive transient surveys in operation, and it is the only survey which covers the whole sky at high spatial resolution (subarcsecond), including the Galactic plane and bulge. © S. T. Hodgkin et al. 2021
A somatotrofina bovina recombinante sobre a ovulação, condição corporal e nĂveis sĂ©ricos de colesterol e glicose em ovinos
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