1,419 research outputs found
Predicted Planck Extragalactic Point Source Catalogue
An estimation of the number and amplitude (in flux) of the extragalactic
point sources that will be observed by the Planck Mission is presented in this
paper. The study is based on the Mexican Hat wavelet formalism introduced by
Cayon et al. 2000. Simulations at Planck observing frequencies are analysed,
taking into account all the possible cosmological, Galactic and Extragalactic
emissions together with noise. With the technique used in this work the Planck
Mission will produce a catalogue of extragalactic point sources above fluxes:
1.03 Jy (857 GHz), 0.53 Jy (545 GHz), 0.28 Jy (353 GHz), 0.24 Jy (217 GHz),
0.32 Jy (143 GHz), 0.41 Jy (100 GHz HFI), 0.34 Jy (100 GHz LFI), 0.57 Jy (70
GHz), 0.54 Jy (44 GHz) and 0.54 Jy (30 GHz), which are only slightly model
dependent (see text). Amplitudes of these sources are estimated with errors
below 15%. Moreover, we also provide a complete catalogue (for the point
sources simulation analysed) with errors in the estimation of the amplitude
below 10%. In addition we discuss the possibility of identifying different
point source populations in the Planck catalogue by estimating their spectral
indices.Comment: 13 pages, 2 figures, submitted to MNRA
C-Band All-Sky Survey: A First Look at the Galaxy
We present an analysis of the diffuse emission at 5 GHz in the first quadrant
of the Galactic plane using two months of preliminary intensity data taken with
the C-Band All Sky Survey (C-BASS) northern instrument at the Owens Valley
Radio Observatory, California. Combining C-BASS maps with ancillary data to
make temperature-temperature plots we find synchrotron spectral indices of
between 0.408 GHz and 5 GHz and between 1.420 GHz and 5 GHz for ,
. Through the subtraction of a radio recombination
line (RRL) free-free template we determine the synchrotron spectral index in
the Galactic plane () to be between
0.408 GHz and 5 GHz, with a contribution of per cent from free-free
emission at 5\,GHz. These results are consistent with previous low frequency
measurements in the Galactic plane. By including C-BASS data in spectral fits
we demonstrate the presence of anomalous microwave emission (AME) associated
with the HII complexes W43, W44 and W47 near 30 GHz, at 4.4 sigma, 3.1 sigma
and 2.5 sigma respectively. The CORNISH VLA 5 GHz source catalogue rules out
the possibility that the excess emission detected around 30\;GHz may be due to
ultra-compact HII regions. Diffuse AME was also identified at a 4 sigma level
within , between 5
GHz and 22.8 GHz.Comment: 16 pages, 9 figures, submitted to MNRAS, referee's corrections made,
awaiting for final approval for publicatio
Cerebral malaria model applying human brain organoids
Neural injuries in cerebral malaria patients are a significant cause of morbidity and mortality. Nevertheless, a comprehensive research approach to study this issue is lacking, so herein we propose an in vitro system to study human cerebral malaria using cellular approaches. Our first goal was to establish a cellular system to identify the molecular alterations in human brain vasculature cells that resemble the blood–brain barrier (BBB) in cerebral malaria (CM). Through transcriptomic analysis, we characterized specific gene expression profiles in human brain microvascular endothelial cells (HBMEC) activated by the Plasmodium falciparum parasites. We also suggest potential new genes related to parasitic activation. Then, we studied its impact at brain level after Plasmodium falciparum endothelial activation to gain a deeper understanding of the physiological mechanisms underlying CM. For that, the impact of HBMEC-P. falciparum-activated secretomes was evaluated in human brain organoids. Our results support the reliability of in vitro cellular models developed to mimic CM in several aspects. These systems can be of extreme importance to investigate the factors (parasitological and host) influencing CM, contributing to a molecular understanding of pathogenesis, brain injury, and dysfunction.This research was funded by National funds through the Foundation for Science and
Technology (FCT) SFRH/BD/131540/2017, SFRH/BD/5813/2020, COVID/BD/152416/2022 and
UMINHO/BIM-CNCG/2022/143. This work has been funded by ICVS Scientific Microscopy Platform, member of the national infrastructure PPBI - Portuguese Platform of Bioimaging (PPBIPOCI-01-0145-FEDER-022122; by National funds, through the FCT—project UIDB/50026/2020
and UIDP/50026/2020. Moreover, this work was funded by IF/00143/2015/CP1294/CT0001,
PTDC/SAU-PAR/2766/2021 and UIDB/04469/2020. O.M. is funded by the project NORTE-01-
0247-FEDER-045914, supported by POFC–COMPETE and FCT, under the programs PT2020 and
NORTE2020. M.I.V. thanks FCT for her contract funding provided through 2020.03113.CEECIND.info:eu-repo/semantics/publishedVersio
Identification of the alpha-enolase P46 in the extracellular membrane vesicles of Bacteroides fragilis
A new analysis procedure to extract fusion excitation function with large beam energy dispersions: application to the 6Li+120Sn and 7Li+119Sn
In the present paper it is described an analysis procedure suited for experiments where cross-sections strongly varying with energy are measured using beams having large energy dispersion. These cross-sections are typically the sub-barrier fusion excitation function of reactions induced by radioactive beams. The large beam energy dispersion, typical of these experiments, can lead to ambiguities in the association of the effective beam energy to the reaction product yields and consequently to an error in the determination of the excitation function. As a test case, the approach is applied to the experiments 6 Li+ 120 Sn and 7 Li+ 119 Sn measured in the energy range 14 MeV ≤ E c.m. ≤28 MeV. The complete fusion cross sections are deduced from activation measurements using the stacked target technique. The results of these experiments, that employ the two weakly-bound stable Li isotopes, show that the complete fusion cross sections above the barrier are suppressed of about 70% and 85% with respect to the Universal Fusion Function, used as a standard reference, in the 6 Li and 7 Li induced reactions respectively. Moreover, the excitation functions of the two systems at energies below the barrier, do not show significant differences, despite the two systems have different n -transfer Q value
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
Establishment of local wastewater-based surveillance programmes in response to the spread and infection of COVID-19 – case studies from South Africa, the Netherlands, Turkey and England
The COVID-19 pandemic has resulted in over 340 million infection cases (as of 21 January 2022) and more than 5.57 million deaths globally. In reaction, science, technology and innovation communities across the globe have organised themselves to contribute to national responses to COVID-19 disease. A significant contribution has been from the establishment of wastewater-based epidemiological (WBE) surveillance interventions and programmes for monitoring the spread of COVID-19 in at least 55 countries. Here, we examine and share experiences and lessons learnt in establishing such surveillance programmes. We use case studies to highlight testing methods and logistics considerations associated in scaling the implementing of such programmes in South Africa, the Netherlands, Turkey and England. The four countries were selected to represent different regions of the world and the perspective based on the considerable progress made in establishing and implementing their national WBE programmes. The selected countries also represent different climatic zones, economies, and development stages, which influence the implementation of national programmes of this nature and magnitude. In addition, the four countries' programmes offer good experiences and lessons learnt since they are systematic, and cover extensive areas, disseminate knowledge locally and internationally and partnered with authorities (government). The programmes also strengthened working relations and partnerships between and among local and global organisations. This paper shares these experiences and lessons to encourage others in the water and public health sectors on the benefits and value of WBE in tackling SARS-CoV-2 and related future circumstances
Human Apolipoprotein A-I-Derived Amyloid: Its Association with Atherosclerosis
Amyloidoses constitute a group of diseases in which soluble proteins aggregate and deposit extracellularly in tissues. Nonhereditary apolipoprotein A-I (apoA-I) amyloid is characterized by deposits of nonvariant protein in atherosclerotic arteries. Despite being common, little is known about the pathogenesis and significance of apoA-I deposition. In this work we investigated by fluorescence and biochemical approaches the impact of a cellular microenvironment associated with chronic inflammation on the folding and pro-amyloidogenic processing of apoA-I. Results showed that mildly acidic pH promotes misfolding, aggregation, and increased binding of apoA-I to extracellular matrix elements, thus favoring protein deposition as amyloid like-complexes. In addition, activated neutrophils and oxidative/proteolytic cleavage of the protein give rise to pro amyloidogenic products. We conclude that, even though apoA-I is not inherently amyloidogenic, it may produce non hereditary amyloidosis as a consequence of the pro-inflammatory microenvironment associated to atherogenesis
Recurrence of Primary Sclerosing Cholangitis After Liver Transplant in Children : An International Observational Study
Background and Aims Recurrent primary sclerosing cholangitis (rPSC) following liver transplant (LT) has a negative impact on graft and patient survival; little is known about risk factors for rPSC or disease course in children. Approach and Results We retrospectively evaluated risk factors for rPSC in 140 children from the Pediatric PSC Consortium, a multicenter international registry. Recipients underwent LT for PSC and had >90 days of follow-up. The primary outcome, rPSC, was defined using Graziadei criteria. Median follow-up after LT was 3 years (interquartile range 1.1-6.1). rPSC occurred in 36 children, representing 10% and 27% of the subjects at 2 years and 5 years following LT, respectively. Subjects with rPSC were younger at LT (12.9 vs. 16.2 years), had faster progression from PSC diagnosis to LT (2.5 vs. 4.1 years), and had higher alanine aminotransferase (112 vs. 66 IU/L) at LT (all P < 0.01). Inflammatory bowel disease was more prevalent in the rPSC group (86% vs. 66%; P = 0.025). After LT, rPSC subjects had more episodes of biopsy-proved acute rejection (mean 3 vs. 1; P < 0.001), and higher prevalence of steroid-refractory rejection (41% vs. 20%; P = 0.04). In those with rPSC, 43% developed complications of portal hypertension, were relisted for LT, or died within 2 years of the diagnosis. Mortality was higher in the rPSC group (11.1% vs. 2.9%; P = 0.05). Conclusions The incidence of rPSC in this cohort was higher than previously reported, and was associated with increased morbidity and mortality. Patients with rPSC appeared to have a more aggressive, immune-reactive phenotype. These findings underscore the need to understand the immune mechanisms of rPSC, to lay the foundation for developing new therapies and improve outcomes in this challenging population.Peer reviewe
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