3,557 research outputs found
La cultura del entretenimiento en la televisión un análisis de caso de la popularidad y la recepción del programa showmatch
El propósito fundamental de este trabajo fue que a través de un análisis de la cultura de entretenimiento en la televisión, se estudió un caso específico relacionado con la popularidad y la recepción del programa Showmatch, conducido por el presentador argentino Marcelo Tinelli, donde se abordaron varios temas que cotidianamente se presentan en dicho programa. Los contenidos del estudio tienen varias aristas, se refieren a la popularidad y la recepción del programa en un sector determinado de la población quiteña. Otro de los tópicos tratados es el entretenimiento y el consumo que producen estos programas televisivos en la gente y como afectan en sus emociones y sensibilidades, logrando identificarse con sus actores y su conductor. Es importante el tratamiento que se da al carisma y popularidad del presentador de televisión, Marcelo Tinelli y su influencia dentro de la sociedad argentina y sus repercusiones en Sudamérica. La investigación tiene dos capítulos, que habla entre otras cosas, del desarrollo cultural, los mass media, la televisión, el consumo, la recepción, el entretenimiento, indicadores de estudio, características del programa en cuestión, etc., todo ello, tomando en cuenta la opinión de varios autores. El objetivo de mostrar una mirada desde el campo académico a los entretelones de un programa de televisión muy popular en Argentina y que tiene una apreciable audiencia en la ciudad de Quito, se cumplió porque se evidencia el comportamiento de la audiencia y sus reacciones ante un producto comunicacional enmarcado dentro de la cultura popular. Productos de este tipo se presentan a diario en los medios de comunicación a nivel nacional e internacional, unos con mejor producción que otros, (Showmatch se caracteriza por una gran producción) aunque los contenidos no varíen demasiado y por eso la importancia del estudio
Correlation between MGMT promoter methylation and response to temozolomide-based therapy in neuroendocrine neoplasms: an observational retrospective multicenter study
Purpose: Temozolomide (TEM) based therapy has been reported being effective in the treatment of metastatic neuroendocrine neoplasms (NEN), with response rates ranging from 30 to 70%. Among patients affected by advanced glioblastoma or melanoma and treated with TEM, loss of tumoral O6-methylguanine DNA methyltransferase (MGMT) is correlated with improved survival. In NEN patients, the role of MGMT deficiency in predicting clinical outcomes of TEM treatment is still under debate. Methods: In this study we evaluated 95 patients with advanced NENs undergoing treatment with TEM-based therapy. MGMT promoter methylation status was evaluated with two techniques: methylation specific-polymerase chain reaction or pyrosequencing. Results: Treatment with TEM-based therapy was associated with an overall response rate of 27.4% according to RECIST criteria (51.8% of patients with and 17.7% without MGMT promoter methylation). Response to therapy, progression free survival and overall survival was correlated to MGMT status at univariate and multivariate analysis. Methylation of MGMT promoter could be a strong predictive factor of objective response and an important prognostic factor of a longer PFS and OS. Conclusion: According to our results, MGMT methylation status, evaluated with methylation specific-polymerase chain reaction or pyrosequencing, should have an important role in patients with metastatic NENs, in order to guide therapeutic options. These results need further confirmation with prospective studies
The Swift X-ray flaring afterglow of GRB 050607
The unique capability of the Swift satellite to perform a prompt and
autonomous slew to a newly detected Gamma-Ray Burst (GRB) has yielded the
discovery of interesting new properties of GRB X-ray afterglows, such as the
steep early lightcurve decay and the frequent presence of flares detected up to
a few hours after the GRB trigger. We present observations of GRB 050607, the
fourth case of a GRB discovered by Swift with flares superimposed on the
overall fading X-ray afterglow. The flares of GRB 050607 were not symmetric as
in previously reported cases, showing a very steep rise and a shallower decay,
similar to the Fast Rise, Exponential Decay that are frequently observed in the
gamma-ray prompt emission. The brighter flare had a flux increase by a factor
of approximately 25,peaking for 30 seconds at a count rate of approximately 30
counts s-1, and it presented hints of addition short time scale activity during
the decay phase. There is evidence of spectral evolution during the flares. In
particular, at the onset of the flares the observed emission was harder, with a
gradual softening as each flare decayed. The very short time scale and the
spectral variability during the flaring activity are indicators of possible
extended periods of energy emission by the GRB central engine. The flares were
followed by a phase of shallow decay, during which the forward shock was being
refreshed by a long-lived central engine or by shells of lower Lorentz factors,
and by a steepening after approximately 12 ks to a decay slope considered
typical of X-ray afterglows.Comment: 23 pages, 5 figures, Accepted by the Astrophysical Journa
Swift XRT Observations of the Afterglow of XRF 050416A
Swift discovered XRF 050416A with the BAT and began observing it with its
narrow field instruments only 64.5 s after the burst onset. Its very soft
spectrum classifies this event as an X-ray flash. The afterglow X-ray emission
was monitored up to 74 days after the burst. The X-ray light curve initially
decays very fast, subsequently flattens and eventually steepens again, similar
to many X-ray afterglows. The first and second phases end about 172 and 1450 s
after the burst onset, respectively. We find evidence of spectral evolution
from a softer emission with photon index Gamma ~ 3.0 during the initial steep
decay, to a harder emission with Gamma ~ 2.0 during the following evolutionary
phases. The spectra show intrinsic absorption in the host galaxy. The
consistency of the initial photon index with the high energy BAT photon index
suggests that the initial phase of the X-ray light curve may be the low-energy
tail of the prompt emission. The lack of jet break signatures in the X-ray
afterglow light curve is not consistent with empirical relations between the
source rest-frame peak energy and the collimation-corrected energy of the
burst. The standard uniform jet model can give a possible description of the
XRF 050416A X-ray afterglow for an opening angle larger than a few tens of
degrees, although numerical simulations show that the late time decay is
slightly flatter than expected from on-axis viewing of a uniform jet. A
structured Gaussian-type jet model with uniform Lorentz factor distribution and
viewing angle outside the Gaussian core is another possibility, although a full
agreement with data is not achieved with the numerical models explored.Comment: Accepted for publication on ApJ; replaced with revised version: part
of the discussion moved in an appendix; 11 pages, 6 figures; abstract
shortened for posting on astro-p
The Highly Energetic Expansion of SN2010bh Associated with GRB 100316D
We present the spectroscopic and photometric evolution of the nearby (z =
0.059) spectroscopically confirmed type Ic supernova, SN 2010bh, associated
with the soft, long-duration gamma-ray burst (X-ray flash) GRB 100316D.
Intensive follow-up observations of SN 2010bh were performed at the ESO Very
Large Telescope (VLT) using the X-shooter and FORS2 instruments. Owing to the
detailed temporal coverage and the extended wavelength range (3000--24800 A),
we obtained an unprecedentedly rich spectral sequence among the hypernovae,
making SN 2010bh one of the best studied representatives of this SN class. We
find that SN 2010bh has a more rapid rise to maximum brightness (8.0 +/- 1.0
rest-frame days) and a fainter absolute peak luminosity (L_bol~3e42 erg/s) than
previously observed SN events associated with GRBs. Our estimate of the ejected
(56)Ni mass is 0.12 +/- 0.02 Msun. From the broad spectral features we measure
expansion velocities up to 47,000 km/s, higher than those of SNe 1998bw (GRB
980425) and 2006aj (GRB 060218). Helium absorption lines He I lambda5876 and He
I 1.083 microm, blueshifted by ~20,000--30,000 km/s and ~28,000--38,000 km/s,
respectively, may be present in the optical spectra. However, the lack of
coverage of the He I 2.058 microm line prevents us from confirming such
identifications. The nebular spectrum, taken at ~186 days after the explosion,
shows a broad but faint [O I] emission at 6340 A. The light-curve shape and
photospheric expansion velocities of SN 2010bh suggest that we witnessed a
highly energetic explosion with a small ejected mass (E_k ~ 1e52 erg and M_ej ~
3 Msun). The observed properties of SN 2010bh further extend the heterogeneity
of the class of GRB supernovae.Comment: 37 pages and 12 figures (one-column pre-print format), accepted for
publication in Ap
Gamma Ray Bursts Flares detected and observed by the Swift Satellite
The detection of flares with the Swift satellite triggered a lot of
bservational and theoretical interest in these phenomena. As a consequence a
large analysis effort started within the community to characterize the
phenomenon and at the same time a variety of theoretical speculations have been
proposed to explain it. In this presentation we discuss part of the results we
obtained analyzing a first statistical sample of GRBs observed with Swift. The
first goal of this research is very simple: derive those observational
properties that could distinguish between internal and external shock and
between an ever active central engine and delayed shocks (refreshing) related
to a very small initial Lorentz bulk factor. We discuss first the method of
analysis and the morphology evidencing the similarities such flares have with
the prompt emission pulses. We conclude that GRB flares are due to internal
shocks and leave still open the question of whether or not the central engine
is active for a time of the order of 105 seconds after the prompt emission.Comment: Proceedings of the Beijing COSPAR Assembly 2006; submitted Nov 2,
200
Factors Associated With Severe Gastrointestinal Diagnoses in Children With SARS-CoV-2 Infection or Multisystem Inflammatory Syndrome
Importance
Severe gastrointestinal (GI) manifestations have been sporadically reported in children with COVID-19; however, their frequency and clinical outcome are unknown.
Objective
To describe the clinical, radiological, and histopathologic characteristics of children with COVID-19 presenting with severe GI manifestations to identify factors associated with a severe outcome.
Design, Setting, and Participants
A multicenter retrospective cohort study (February 25, 2020, to January 20, 2021) enrolled inpatient and outpatient children (aged <18 years) with acute SARS-CoV-2 infection, confirmed by positive real-time reverse-transcriptase–polymerase chain reaction on nasopharyngeal swab or fulfilling the US Centers for Disease Control and Prevention criteria for multisystem inflammatory syndrome in children (MIS-C). The study was conducted by pediatricians working in primary care or hospitals in Italy participating in the COVID-19 Registry of the Italian Society of Pediatric Infectious Diseases.
Main Outcomes and Measures
The occurrence of severe GI manifestations, defined by a medical and/or radiological diagnosis of acute abdomen, appendicitis (complicated or not by perforation and/or peritonitis), intussusception, pancreatitis, abdominal fluid collection, and diffuse adenomesenteritis requiring surgical consultation, occurring during or within 4 to 6 weeks after infection with SARS-CoV-2 infection. Logistic regression was used to estimate odds ratios (ORs) with 95% CIs of factors potentially associated with severe outcomes.
Results
Overall, 685 children (386 boys [56.4%]; median age, 7.3 [IQR, 1.6-12.4] years) were included. Of these children, 628 (91.7%) were diagnosed with acute SARS-CoV-2 infection and 57 (8.3%) with MIS-C. The presence of GI symptoms was associated with a higher chance of hospitalization (OR, 2.64; 95% CI, 1.89-3.69) and intensive care unit admission (OR, 3.90; 95% CI, 1.98–7.68). Overall, 65 children (9.5%) showed severe GI involvement, including disseminated adenomesenteritis (39.6%), appendicitis (33.5%), abdominal fluid collection (21.3%), pancreatitis (6.9%), or intussusception (4.6%). Twenty-seven of these 65 children (41.5%) underwent surgery. Severe GI manifestations were associated with the child’s age (5-10 years: OR, 8.33; 95% CI, 2.62-26.5; >10 years: OR, 6.37; 95% CI, 2.12-19.1, compared with preschool-age), abdominal pain (adjusted OR [aOR], 34.5; 95% CI, 10.1-118), lymphopenia (aOR, 8.93; 95% CI, 3.03-26.3), or MIS-C (aOR, 6.28; 95% CI, 1.92-20.5). Diarrhea was associated with a higher chance of adenomesenteritis (aOR, 3.13; 95% CI, 1.08-9.12) or abdominal fluid collection (aOR, 3.22; 95% CI, 1.03-10.0).
Conclusions and Relevance
In this multicenter cohort study of Italian children with SARS-CoV-2 infection or MIS-C, 9.5% of the children had severe GI involvement, frequently associated with MIS-C. These findings suggest that prompt identification may improve the management of serious complications
GRB Radiative Efficiencies Derived from the Swift Data: GRBs vs. XRFs, Long vs. Short
We systematically analyze the prompt emission and the early afterglow data of
a sample of 31 GRBs detected by {\em Swift} before September 2005, and estimate
the GRB radiative efficiency. BAT's narrow band inhibits a precise
determination of the GRB spectral parameters, and we have developed a method to
estimate these parameters with the hardness ratio information. The shallow
decay component commonly existing in early X-ray afterglows, if interpreted as
continuous energy injection in the external shock, suggests that the GRB
efficiency previously derived from the late-time X-ray data were not reliable.
We calculate two radiative efficiencies using the afterglow kinetic energy E_K
derived at the putative deceleration time t_{dec}) and at the break time (t_b)
when the energy injection phase ends, respectively. At t_b XRFs appear to be
less efficient than normal GRBs. However, when we analyze the data at t_{dec}
XRFs are found to be as efficient as GRBs. Short GRBs have similar radiative
efficiencies to long GRBs despite of their different progenitors. Twenty-two
bursts in the sample are identified to have the afterglow cooling frequency
below the X-ray band. Assuming \epsilon_e = 0.1, we find \eta_\gamma(t_b)
usually 90%.
Nine GRBs in the sample have the afterglow cooling frequency above the X-ray
band for a very long time. This suggests a very small \epsilon_B and/or a very
low ambient density n.Comment: 43 pages, 10 figures, ApJ, in pres
Swift XRT Observations of the Afterglow of GRB 050319
Swift discovered the high redshift GRB 050319 with the Burst Alert Telescope
and began observing with its narrow field instruments only 225 s after the
burst onset. The afterglow X-ray emission was monitored by the XRT up to 28
days after the burst. The light curve shows a decay with three different
phases, each characterized by a distinct slope: an initial steep decay with a
power law index of ~ 5.5, a second phase characterized by a flat decay slope of
\~ 0.54, and a third phase with a decay slope of ~ 1.14. During the first phase
the spectral energy distribution is softer than in the following two phases and
the photon index is consistent with the GRB prompt spectrum. The extrapolation
of the BAT light curve to the XRT band suggests that the initial fast decaying
phase of the XRT afterglow might be the low energy tail of the prompt emission.
The second break in the afterglow light curve occurs about 27000 s after the
burst. The spectral energy distribution before and after the second break does
not change and it can be tentatively interpreted as a jet break or the end of a
delayed or continuous energy injection phase.Comment: 15 pages, 2 figures. Accepted for publication in Ap
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