1,466 research outputs found
Factors Associated with Pre-drinking Among Nightclub Patrons in the City of SĂŁo Paulo
Aims: the aim of the study was to describe the phenomenon of pre-drinking (alcohol consumption before entering nightclubs or bars) and to identify factors associated with pre-drinking practices among patrons in the city of São Paulo, Brazil. Methods: Individual-level data were collected by a portal survey of 2422 patrons at the entrance and at the exit of 31 nightclubs. the nightclubs were selected by two-stage sampling using a probability proportional to the establishments' capacity in the first stage and a systematic sample of patrons in the second stage. Breath alcohol concentration (BrAC) was measured. Face-to-face interview identified pre-drinking characteristics and past-year risk behaviors. Analysis used sample weights to compensate for nightclubs or patrons that were possibly over- or under-represented. Results: of the study participants, 41.3% (95% confidence interval (CI) = 33.7-49.3) engaged in pre-drinking on the night of the interview. Being male (odds ratio (OR) = 1.98, 95% CI = 1.45-2.71), past-year binge drinking (OR = 2.28, 95% CI = 1.70-3.07), previous episodes of severe effects from drunkenness (OR = 1.77, 95% CI = 1.40-2.22) and sexual risk behavior (OR = 1.67, 95% CI = 1.20-2.33) were associated with recent pre-drinking. Pre-drinking predicted higher BrACs at the nightclub exit. Conclusion: Pre-drinking is prevalent among nightclub patrons and associated with risk behaviors, and is associated with alcohol intoxication at nightclub exits. Environmental prevention strategies must consider pre-drinking as a potential risk factor for alcohol intoxication in nightclubs.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Dept Prevent Med, Epidemiol Sect, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Informat Hlth, Sect Stat, São Paulo, BrazilUniversidade Federal de São Paulo, Sect Bioestat, Dept Prevent Med, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Prevent Med, Epidemiol Sect, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Informat Hlth, Sect Stat, São Paulo, BrazilUniversidade Federal de São Paulo, Sect Bioestat, Dept Prevent Med, São Paulo, BrazilFAPESP: 2011/51658-0FAPESP: 2012/03832-4Web of Scienc
A 4 Gyr M-dwarf Gyrochrone from CFHT/MegaPrime Monitoring of the Open Cluster M67
We present stellar rotation periods for late K- and early M-dwarf members of
the 4 Gyr old open cluster M67 as calibrators for gyrochronology and tests of
stellar spin-down models. Using Gaia EDR3 astrometry for cluster membership and
Pan-STARRS (PS1) photometry for binary identification, we build this set of
rotation periods from a campaign of monitoring M67 with the
Canada-France-Hawaii Telescope's MegaPrime wide field imager. We identify 1807
members of M67, of which 294 are candidate single members with significant
rotation period detections. Moreover, we fit a polynomial to the period versus
color-derived effective temperature sequence observed in our data. We find that
the rotation of very cool dwarfs can be explained by a simple solid-body
spin-down between 2.7 and 4 Gyr. We compare this rotational sequence to the
predictions of gyrochronological models and find that the best match is
Skumanich-like spin-down, P_rot \propto t^0.62, applied to the sequence of
Ruprecht 147. This suggests that, for spectral types K7-M0 with near-solar
metallicity, once a star resumes spinning down, a simple Skumanich-like is
sufficient to describe their rotation evolution, at least through the age of
M67. Additionally, for stars in the range M1-M3, our data show that spin-down
must have resumed prior to the age of M67, in conflict with predictions of the
latest spin-down models.Comment: 21 pages, 16 figures, Accepted for publication by Ap
MELISSA: System Description and Spectral Features of Pre- and Post-Midnight F-Region Echoes
Most of the lowâlatitude ionospheric radar observations in South America come from the Jicamarca Radio Observatory, located in the western longitude sector (âŒ75°W). The deployment of the 30 MHz FAPESPâClemsonâINPE (FCI) coherent backscatter radar in the magnetic equatorial site of SĂŁo Luis, Brazil, in 2001 allowed observations to be made in the eastern sector (âŒ45°W). However, despite being operational for several years (2001â2012), FCI only made observations during daytime and preâmidnight hours, with a few exceptions. Here, we describe an upgraded system that replaced the FCI radar and present results of fullânight Fâregion observations. This radar is referred to as Measurements of Equatorial and Lowâlatitude Ionospheric irregularities over SĂŁo LuĂs, South America (MELISSA), and made observations between March 2014 and December 2018. We present results of our analyses of preâ and postâmidnight Fâregion echoes with focus on the spectral features of postâmidnight echoes and how they compare to spectra of echoes observed in the postâsunset sector. The radar observations indicate that postâmidnight Fâregion irregularities were generated locally and were not a result of âfossilâ structures generated much earlier in time (in other longitude sectors) and that drifted into the radar fieldâofâview. This also includes cases where the echoes are weak and that would be associated with decaying equatorial spread F (ESF) structures. Collocated digisonde observations show modest but noticeable Fâregion apparent uplifts prior to postâmidnight ESF events. We associate the equatorial uplifts with disturbed dynamo effects and with destabilizing Fâregion conditions leading to ESF development
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Macrophage migration inhibitory factor: a mediator of matrix metalloproteinase-2 production in rheumatoid arthritis
Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by destruction of bone and cartilage, which is mediated, in part, by synovial fibroblasts. Matrix metalloproteinases (MMPs) are a large family of proteolytic enzymes responsible for matrix degradation. Macrophage migration inhibitory factor (MIF) is a cytokine that induces the production of a large number of proinflammatory molecules and has an important role in the pathogenesis of RA by promoting inflammation and angiogenesis. In the present study, we determined the role of MIF in RA synovial fibroblast MMP production and the underlying signaling mechanisms. We found that MIF induces RA synovial fibroblast MMP-2 expression in a time-dependent and concentration-dependent manner. To elucidate the role of MIF in MMP-2 production, we produced zymosan-induced arthritis (ZIA) in MIF gene-deficient and wild-type mice. We found that MMP-2 protein levels were significantly decreased in MIF gene-deficient compared with wild-type mice joint homogenates. The expression of MMP-2 in ZIA was evaluated by immunohistochemistry (IHC). IHC revealed that MMP-2 is highly expressed in wild-type compared with MIF gene-deficient mice ZIA joints. Interestingly, synovial lining cells, endothelial cells, and sublining nonlymphoid mononuclear cells expressed MMP-2 in the ZIA synovium. Consistent with these results, in methylated BSA (mBSA) antigen-induced arthritis (AIA), a model of RA, enhanced MMP-2 expression was also observed in wild-type compared with MIF gene-deficient mice joints. To elucidate the signaling mechanisms in MIF-induced MMP-2 upregulation, RA synovial fibroblasts were stimulated with MIF in the presence of signaling inhibitors. We found that MIF-induced RA synovial fibroblast MMP-2 upregulation required the protein kinase C (PKC), c-jun N-terminal kinase (JNK), and Src signaling pathways. We studied the expression of MMP-2 in the presence of PKC isoform-specific inhibitors and found that the PKCÎŽ inhibitor rottlerin inhibits MIF-induced RA synovial fibroblast MMP-2 production. Consistent with these results, MIF induced phosphorylation of JNK, PKCÎŽ, and c-jun. These results indicate a potential novel role for MIF in tissue destruction in RA
In search of gravity mode signatures in main sequence solar-type stars observed by Kepler
Gravity modes (g modes), mixed gravito-acoustic modes (mixed modes), and
gravito-inertial modes (gi modes) possess unmatched properties as probes for
stars with radiative interiors. The structural and dynamical constraints that
they are able to provide cannot be accessed by other means. While they provide
precious insights into the internal dynamics of evolved stars as well as
massive and intermediate-mass stars, their non-detection in main sequence (MS)
solar-type stars make them a crucial missing piece in our understanding of
angular momentum transport in radiative zones and stellar rotational evolution.
In this work, we aim to apply certain analysis tools originally developed for
helioseismology in order to look for g-mode signatures in MS solar-type stars.
We select a sample of the 34 most promising MS solar-type stars with Kepler
four-year long photometric time series. All these stars are well-characterised
late F-type stars with thin convective envelopes, fast convective flows, and
stochastically excited acoustic modes (p modes). For each star, we compute the
background noise level of the Fourier power spectrum to identify significant
peaks at low frequency. After successfully detecting individual peaks in 12
targets, we further analyse four of them and observe distinct patterns of
surrounding peaks with a low probability of being noise artifacts. Comparisons
with the predictions from reference models suggest that these patterns are
compatible with the presence of non-asymptotic low-order pure g modes, pure p
modes, and mixed modes. Given their sensitivity to both the convective core
interface stratification and the coupling between p- and g-mode resonant
cavities, such modes are able to provide strong constraints on the structure
and evolutionary states of the related targets. [abridged]Comment: 19 pages, 19 figures, accepted for publication in A&
Room temperature ferromagnetism in intercalated Fe3-xGeTe2 van der Waals magnet
Among several well-known transition metal-based compounds, the van der Waals
(vdW) Fe3-xGeTe2 (FGT) magnet is a strong candidate for use in two-dimensional
(2D) magnetic devices due to its strong perpendicular magnetic anisotropy,
sizeable Curie temperature (TC ~ 154 K), and versatile magnetic character that
is retained in the low-dimensional limit. While the TC remains far too low for
practical applications, there has been a successful push toward improving it
via external driving forces such as pressure, irradiation, and doping. Here we
present experimental evidence of a novel room-temperature (RT) ferromagnetic
phase induced by the electrochemical intercalation of common tetrabutylammonium
cations (TBA+) into FGT bulk crystals. We obtained Curie temperatures as high
as 350 K with chemical and physical stability of the intercalated compound. The
temperature-dependent Raman measurements in combination with vdW-corrected ab
initio calculations suggest that charge transfer (electron doping) upon
intercalation could lead to the observation of RT ferromagnetism. This work
demonstrates that molecular intercalation is a viable route in realizing
high-temperature vdW magnets in an inexpensive and reliable manner
Everyone on Radio
This adaptation of Everyman was scheduled for production on the main stage in the Kline Theatre of Gettysburg College. With the onset of COVID-19 and the ensuing advent of distance-learning, that could no longer happen, and originally that was a crushing disappointment. But the show must go on, especially when that show is âEveryman,â an especially apt theatrical choice for a pestilential year. Everyman offers exciting possibilities for audio drama, especially considering the playâs emphasis on the internal struggle of the individual facing death; Everyone on Radio attempts to make the most of these aspects of the play. Never willing to blink in the face of doom, the students in this class rose to the occasion with incredible pluck, optimism, and good humor. In particular, Lauren âHelpingâ Hand, the peer associate for this yearâs course, led the pivot to the podcast platform, and this production is as much hers as anyoneâs: She was chief cheerleader, coordinator, and executive producer, in tandem with Joey âMagic Fingersâ Maguschak, who acted as senior sound engineer and producer
Influence of Magnetic Activity on the Determination of Stellar Parameters Through Asteroseismology
Magnetic activity changes the gravito-acoustic modes of solar-like stars and in particular their frequencies. There is an angular-degree dependence that is believed to be caused by the non-spherical nature of the magnetic activity in the stellar convective envelope. These changes in the mode frequencies could modify the small separation of low-degree modes (i.e., frequency difference between consecutive quadrupole and radial modes), which is sensitive to the core structure and hence to the evolutionary stage of the star. Determining global stellar parameters such as the age using mode frequencies at a given moment of the magnetic activity cycle could lead to biased results. Our estimations show that in general these errors are lower than other systematic uncertainties, but in some circumstances they can be as high as 10% in age and of a few percent in mass and radius. In addition, the frequency shifts caused by the magnetic activity are also frequency dependent. In the solar case this is a smooth function that will mostly be masked by the filtering of the so-called surface effects. However, the observations of other stars suggest that there is an oscillatory component with a period close to the one corresponding to the acoustic depth of the He II zone. This could give rise to a misdetermination of some global stellar parameters, such as the helium abundance. Our computations show that the uncertainties introduced by this effect are lower than the 3% level
CMB observations from the CBI and VSA: A comparison of coincident maps and parameter estimation methods
We present coincident observations of the Cosmic Microwave Background (CMB)
from the Very Small Array (VSA) and Cosmic Background Imager (CBI) telescopes.
The consistency of the full datasets is tested in the map plane and the Fourier
plane, prior to the usual compression of CMB data into flat bandpowers. Of the
three mosaics observed by each group, two are found to be in excellent
agreement. In the third mosaic, there is a 2 sigma discrepancy between the
correlation of the data and the level expected from Monte Carlo simulations.
This is shown to be consistent with increased phase calibration errors on VSA
data during summer observations. We also consider the parameter estimation
method of each group. The key difference is the use of the variance window
function in place of the bandpower window function, an approximation used by
the VSA group. A re-evaluation of the VSA parameter estimates, using bandpower
windows, shows that the two methods yield consistent results.Comment: 10 pages, 6 figures. Final version. Accepted for publication in MNRA
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