582 research outputs found
Polarization of the WMAP Point Sources
The detection of polarized sources in the WMAP 5-year data is a very
difficult task. The maps are dominated by instrumental noise and only a handful
of sources show up as clear peaks in the Q and U maps. Optimal linear filters
applied at the position of known bright sources detect with a high level of
significance a polarized flux P from many more sources, but estimates of P are
liable to biases. Using a new technique, named the "filtered fusion technique",
we have detected in polarization, with a significance level greater than 99.99%
in at least one WMAP channel, 22 objects, 5 of which, however, do not have a
plausible low radio frequency counterpart and are therefore doubtful. Estimated
polarized fluxes P < 400 mJy at 23 GHz were found to be severely affected by
the Eddington bias. The corresponding polarized flux limit for Planck/LFI at 30
GHz, obtained via realistic simulations, is 300 mJy. We have also obtained
statistical estimates of, or upper limits to the mean polarization degrees of
bright WMAP sources at 23, 33, 41, and 61 GHz, finding that they are of a few
percent.Comment: 10 pages, 6 figures. Accepted for publication in Ap
Trigonometry of spacetimes: a new self-dual approach to a curvature/signature (in)dependent trigonometry
A new method to obtain trigonometry for the real spaces of constant curvature
and metric of any (even degenerate) signature is presented. The method
encapsulates trigonometry for all these spaces into a single basic
trigonometric group equation. This brings to its logical end the idea of an
absolute trigonometry, and provides equations which hold true for the nine
two-dimensional spaces of constant curvature and any signature. This family of
spaces includes both relativistic and non-relativistic homogeneous spacetimes;
therefore a complete discussion of trigonometry in the six de Sitter,
minkowskian, Newton--Hooke and galilean spacetimes follow as particular
instances of the general approach. Any equation previously known for the three
classical riemannian spaces also has a version for the remaining six
spacetimes; in most cases these equations are new. Distinctive traits of the
method are universality and self-duality: every equation is meaningful for the
nine spaces at once, and displays explicitly invariance under a duality
transformation relating the nine spaces. The derivation of the single basic
trigonometric equation at group level, its translation to a set of equations
(cosine, sine and dual cosine laws) and the natural apparition of angular and
lateral excesses, area and coarea are explicitly discussed in detail. The
exposition also aims to introduce the main ideas of this direct group
theoretical way to trigonometry, and may well provide a path to systematically
study trigonometry for any homogeneous symmetric space.Comment: 51 pages, LaTe
α-Hispanolol Induces Apoptosis and Suppresses Migration and Invasion of Glioblastoma Cells Likely via Downregulation of MMP-2/9 Expression and p38MAPK Attenuation
α-Hispanolol (α-H) is a labdane diterpenoid that has been shown to induce apoptosis in several human cancer cells. However, the effect of α-H in human glioblastoma cells has not been described. In the present work, we have investigated the effects of α-H on apoptosis, migration, and invasion of human glioblastoma cells with the aim of identifying the molecular targets underlying its mechanism of action. The results revealed that α-H showed significant cytotoxicity against human glioma cancer cell lines U87 and U373 in a concentration- and time-dependent manner. This effect was higher in U87 cells and linked to apoptosis, as revealed the increased percentage of sub-G1 population by cell cycle analysis and acquisition of typical features of apoptotic cell morphology. Apoptosis was also confirmed by significant presence of annexin V-positive cells and caspase activation. Pretreatment with caspase inhibitors diminishes the activities of caspase 8, 9, and 3 and maintains the percentage of viable glioblastoma cells, indicating that α-H induced cell apoptosis through both the extrinsic and the intrinsic pathways. Moreover, we also found that α-H downregulated the anti-apoptotic Bcl-2 and Bcl-xL proteins and activated the pro-apoptotic Bid and Bax proteins. On the other hand, α-H exhibited inhibitory effects on the migration and invasion of U87 cells in a concentration-dependent manner. Furthermore, additional experiments showed that α-H treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase MMP-2 and MMP-9 and increased the expression of TIMP-1 inhibitor, probably via p38MAPK regulation. Finally, xenograft assays confirmed the anti-glioma efficacy of α-H. Taken together, these findings suggest that α-H may exert anti-tumoral effects in vitro and in vivo through the inhibition of cell proliferation and invasion as well as by the induction of apoptosis in human glioblastoma cells. This research describes α-H as a new drug that may improve the therapeutic efficacy against glioblastoma tumors.This study was supported by grant PI11/00036, PI14/00055, and PI17/00012 from the FIS, MPY 1410/09 from ISCIII and Spanish Ministry of Health (Instituto de Salud Carlos III; RD12/0036/0059) to SoH and by grants IERPY 1149/16 and IERPY-M 389/18 to AL. L JG was supported by FIS (FI12/00340). SaH was supported by IERPY 1149/16 from ISCIII.S
Late HIV Diagnosis but Earlier Antiretroviral Treatment Initiation in Northwest Spain: Impact of Current Treatment Guidelines.
BACKGROUND: Current HIV treatment guidelines recommend antiretroviral treatment (ART) initiation for all HIV-infected individuals regardless of CD4 count. This study evaluates the immunological and virological status and the clinical characteristics of patients who have started ART in the last 8 years in the Northwest of Spain. METHODS: All HIV-infected patients who have started ART between January 2009 and December 2016 at a reference hospital in the Northwest of Spain were included in this retrospective observational study. Epidemiological, clinical, and immunovirological features and antiretroviral drugs used for initiation were recorded. A statistical analysis was performed using SPSS version 19 software. Categorical and continuous variables were compared by the specific statistical tests, and a logistic regression model was used to identify time associated with Center for Disease Control and Prevention (CDC) categories change. RESULTS: A high proportion of HIV-infected patients (66.7%) had initiated ART with CD4 counts <350 cells/mm(3) in the last 8 years. From these, most of them (68.3%) had <350 CD4 counts at first contact with HIV specialist medical team, 12.2% had no indications for ART initiation in the last clinic visit before ART initiation according to the national guidelines at that moment, 11.0% were lost to follow-up because of lack of compliance with scheduled visits and 8.5% of patients refused treatment. A logistic regression model showed that a delay of one month since the first contact with HIV specialist medical team to ART initiation involves a risk of worsening in the CDC clinical category (odds ratio: 1.02 [95% confidence interval: 1.012-1.029]; P < .001). A trend towards an earlier start of ART was observed during 2015 and 2016, likely influenced by the last treatment guidelines recommendations. CONCLUSION: High proportion of HIV-infected patients (66.7%) had initiated ART with CD4 counts <350 cells/mm(3) in the last 8 years. The main reasons for this problem were analyzed and an important rate of late diagnosis was identified. However, a trend towards an earlier start of ART was observed during 2015 and 2016, likely influenced by the last treatment guidelines recommendations. These findings highlight the need to promote and facilitate HIV testing to reduce the late diagnosis as well as counseling on HIV prevention, treatment, and linkage care
Treatment of atopic dermatitis with abrocitinib in real practice in Spain: efficacy and safety results from a 24-week multicenter study
Background: Abrocitinib, a selective JAK 1 inhibitor, was recently approved in Europe. Despite its approval, real-world data on its efficacy and safety in treating moderate-to-severe atopic dermatitis (AD) remains limited. Objectives: This study aimed to evaluate the short-term effectiveness and safety of abrocitinib in a real-life setting for patients with moderate-to-severe AD. Methods: We conducted a retrospective multicenter study involving adult patients with moderate-to-severe AD who started abrocitinib treatment between May 1, 2023, and September 30, 2023, in 15 Spanish hospitals. Treatment doses were 100 or 200 mg daily, based on clinical assessment. Data collection included patient demographics, AD history, comorbidities, previous treatments, and disease severity indicators such as SCORing atopic dermatitis (SCORAD), Eczema Area and Severity Index (EASI), body surface area, and Peak Pruritus NRS scores at baseline, 4, 12, and 24 weeks. Quality of life was measured using the Dermatology Life Quality Index (DLQI), and safety was assessed by monitoring adverse reactions and various biochemical parameters. Results: The cohort comprised 76 patients with an average age of 33.93 years; 57.89% were male. Before abrocitinib, 36.84% were naĂŻve to advanced therapies. The baseline mean scores were SCORAD 47.04, EASI 21.79, and DLQI 15.01. At Week 24, there were significant improvements: EASI was reduced to 2.81, and 70.58% of the patients achieved EASI 75. However, 18.42% discontinued treatment mainly due to inefficacy or adverse effects. The safety profile was favorable, with 22.37% reporting mild adverse events (AEs) and one serious case of cutaneous lymphoma. Conclusions: This first Spanish series assessing abrocitinib in real-world conditions reveals a significant improvement in AD symptoms and quality of life in a range of severity and prior treatment failures. Abrocitinib was well-tolerated, with few serious AEs, highlighting its potential as an effective treatment option for AD.7 pĂĄgina
Searching for large-scale structures around high-redshift radio galaxies with Herschel
This paper presents the first results of a far-infrared search for protocluster-associated galaxy overdensities using the Spectral and Photometric Imaging REciever (SPIRE) instrument on-board the Herschel Space Observatory. Large (âŒ400âarcmin2) fields surrounding 26 powerful high-redshift radio galaxies (2.0 1028.5 WHzâ1) are mapped at 250, 350 and 500âÎŒm to give a unique wide-field sample. On average, the fields have a higher than expected, compared to blank fields, surface density of 500âÎŒm sources within 6 comoving Mpc of the radio galaxy. The analysis is then restricted to potential protocluster members only, which are identified using a far-infrared colour selection; this reveals significant overdensities of galaxies in two fields, neither of which are previously known protoclusters. The probability of finding two overdensities of this size by chance, given the number of fields observed, is 5 Ă 10â4. Overdensities here exist around radio galaxies with L500âMHz âł 1029 WHzâ1 and z 1014âMâ. However, the large uncertainty in the redshift estimation means that it is possible that these far-infrared overdensities consist of several structures across the redshift range searched
QUIJOTE scientific results -- XIII. Intensity and polarization study of supernova remnants in the QUIJOTE-MFI wide survey: CTB 80, Cygnus Loop, HB 21, CTA 1, Tycho and HB 9
We use the new QUIJOTE-MFI wide survey (11, 13, 17 and 19 GHz) to produce
spectral energy distributions (SEDs), on an angular scale of 1 deg, of the
supernova remnants (SNRs) CTB 80, Cygnus Loop, HB 21, CTA 1, Tycho and HB 9. We
provide new measurements of the polarized synchrotron radiation in the
microwave range. For each SNR, the intensity and polarization SEDs are obtained
and modelled by combining QUIJOTE-MFI maps with ancillary data. In intensity,
we confirm the curved power law spectra of CTB 80 and HB 21 with a break
frequency at 2.0 GHz and 5.0 GHz
respectively; and spectral indices respectively below and above the spectral
break of and for CTB 80, and and
for HB 21. In addition, we provide upper limits on the Anomalous
Microwave Emission (AME), suggesting that the AME contribution is negligible
towards these remnants. From a simultaneous intensity and polarization fit, we
recover synchrotron spectral indices as flat as , and the whole sample
has a mean and scatter of . The polarization fractions have a
mean and scatter of \%. When combining our results with the
measurements from other QUIJOTE studies of SNRs, we find that radio spectral
indices are flatter for mature SNRs, and particularly flatter for CTB 80
() and HB 21 (). In addition, the
evolution of the spectral indices against the SNRs age is modelled with a
power-law function, providing an exponent and amplitude
(normalised at 10 kyr), which are conservative with respect to
previous studies of our Galaxy and the Large Magellanic Cloud.Comment: 33 pages, 15 figure, 15 tables. Submitted to MNRAS. QUIJOTE data maps
available at https://research.iac.es/proyecto/quijot
Planck intermediate results. XLI. A map of lensing-induced B-modes
The secondary cosmic microwave background (CMB) -modes stem from the
post-decoupling distortion of the polarization -modes due to the
gravitational lensing effect of large-scale structures. These lensing-induced
-modes constitute both a valuable probe of the dark matter distribution and
an important contaminant for the extraction of the primary CMB -modes from
inflation. Planck provides accurate nearly all-sky measurements of both the
polarization -modes and the integrated mass distribution via the
reconstruction of the CMB lensing potential. By combining these two data
products, we have produced an all-sky template map of the lensing-induced
-modes using a real-space algorithm that minimizes the impact of sky masks.
The cross-correlation of this template with an observed (primordial and
secondary) -mode map can be used to measure the lensing -mode power
spectrum at multipoles up to . In particular, when cross-correlating with
the -mode contribution directly derived from the Planck polarization maps,
we obtain lensing-induced -mode power spectrum measurement at a significance
level of , which agrees with the theoretical expectation derived
from the Planck best-fit CDM model. This unique nearly all-sky
secondary -mode template, which includes the lensing-induced information
from intermediate to small () angular scales, is
delivered as part of the Planck 2015 public data release. It will be
particularly useful for experiments searching for primordial -modes, such as
BICEP2/Keck Array or LiteBIRD, since it will enable an estimate to be made of
the lensing-induced contribution to the measured total CMB -modes.Comment: 20 pages, 12 figures; Accepted for publication in A&A; The B-mode map
is part of the PR2-2015 Cosmology Products; available as Lensing Products in
the Planck Legacy Archive http://pla.esac.esa.int/pla/#cosmology; and
described in the 'Explanatory Supplement'
https://wiki.cosmos.esa.int/planckpla2015/index.php/Specially_processed_maps#2015_Lensing-induced_B-mode_ma
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