31 research outputs found
Detection of X-ray elongated emission from a ultraluminous X-ray source in the interacting pair of galaxies NGC 5953/5954
We present radio through X-ray results of a bright (10^{40} erg/s in the 0.5
to 8.0 keV band) ultraluminous X-ray source (ULX), CXOU J153434.9+151149, in
the starburst, interacting pair of galaxies NGC 5953/5954. Chandra image of
this ULX shows that it is elongated. From HST/WFPC2/F606W data we have detected
a counterpart of the ULX system with M_{F606W} ~-7.1 \pm 0.7 mag. This optical
counterpart may be either an O-type supergiant star or a young star cluster.
From our Fabry-Perot interferometric observations, we have detected Halpha and
[NII](6584 A) diffuse emission, with velocity gradients up to 60 km/s at the
astrometric corrected Chandra position of the ULX. Different scenarios have
been invoked as to explain the possible nature of CXOU J153434.9+151149. Based
on the observed X-ray morphology of the ULX, we determine that the inclination
angle to the elongated emission will be ~53 deg. Beaming with this geometry
from a stellar-mass black hole system will be inadequate to explain the
observed X-ray luminosity of this ULX. Finally, we suggest that mild-beaming
from a binary black hole with mass more than 50 solar masses, associated with a
young star cluster, is the most favorable scenario that describes the
multiwavelength properties of this ULX. Future observations are highly
essential to determine the nature of this rare object.Comment: 34 pages (referee format), 5 figures, accepted for publication in A
Teleost metamorphosis: the role of thyroid hormone
In most teleosts, metamorphosis encompasses a dramatic post-natal developmental process where the free-swimming larvae undergo a series of morphological, cellular and physiological changes that enable the larvae to become a fully formed, albeit sexually immature, juvenile fish. In all teleosts studied to date thyroid hormones (TH) drive metamorphosis, being the necessary and sufficient factors behind this developmental transition. During metamorphosis, negative regulation of thyrotropin by thyroxine (T4) is relaxed allowing higher whole-body levels of T4 that enable specific responses at the tissue/cellular level. Higher local thyroid cellular signaling leads to cell-specific responses that bring about localized developmental events. TH orchestrate in a spatial-temporal manner all local developmental changes so that in the end a fully functional organism arises. In bilateral teleost species, the most evident metamorphic morphological change underlies a transition to a more streamlined body. In the pleuronectiform lineage (flatfishes), these metamorphic morphological changes are more dramatic. The most evident is the migration of one eye to the opposite side of the head and the symmetric pelagic larva development into an asymmetric benthic juvenile. This transition encompasses a dramatic loss of the embryonic derived dorsal-ventral and left-right axis. The embryonic dorsal-ventral axis becomes the left-right axis, whereas the embryonic left-right axis becomes, irrespectively, the dorsal-ventral axis of the juvenile animal. This event is an unparalleled morphological change in vertebrate development and a remarkable display of the capacity of TH-signaling in shaping adaptation and evolution in teleosts. Notwithstanding all this knowledge, there are still fundamental questions in teleost metamorphosis left unanswered: how the central regulation of metamorphosis is achieved and the neuroendocrine network involved is unclear; the detailed cellular and molecular events that give rise to the developmental processes occurring during teleost metamorphosis are still mostly unknown. Also in flatfish, comparatively little is still known about the developmental processes behind asymmetric development. This review summarizes the current knowledge on teleost metamorphosis and explores the gaps that still need to be challenged.Portuguese Foundation for Science and Technology: (IF/01274/2014)
UID/Multi/04326/2016 (CCMAR)info:eu-repo/semantics/publishedVersio
The Large Observatory for x-ray timing
The Large Observatory For x-ray Timing (LOFT) was studied within ESA M3 Cosmic Vision framework and participated in the final down-selection for a launch slot in 2022-2024. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument, LOFT will study the behaviour of matter under extreme conditions, such as the strong gravitational field in the innermost regions of accretion flows close to black holes and neutron stars, and the supra-nuclear densities in the interior of neutron stars. The science payload is based on a Large Area Detector (LAD, 10 m2 effective area, 2-30 keV, 240 eV spectral resolution, 1° collimated field of view) and a WideField Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). The WFM is equipped with an on-board system for bright events (e.g. GRB) localization. The trigger time and position of these events are broadcast to the ground within 30 s from discovery. In this paper we present the status of the mission at the end of its Phase A study
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
The LOFT mission concept: a status update
The Large Observatory For x-ray Timing (LOFT) is a mission concept which was proposed to ESA as M3 and M4 candidate in the framework of the Cosmic Vision 2015-2025 program. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument and the uniquely large field of view of its wide field monitor, LOFT will be able to study the behaviour of matter in extreme conditions such as the strong gravitational field in the innermost regions close to black holes and neutron stars and the supra-nuclear densities in the interiors of neutron stars. The science payload is based on a Large Area Detector (LAD, >8m2 effective area, 2-30 keV, 240 eV spectral resolution, 1 degree collimated field of view) and a Wide Field Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). The WFM is equipped with an on-board system for bright events (e.g., GRB) localization. The trigger time and position of these events are broadcast to the ground within 30 s from discovery. In this paper we present the current technical and programmatic status of the mission
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Efficacy and Safety of Dupilumab Maintained in Adults â„ 60 Years of Age with Moderate-to-Severe Atopic Dermatitis: Analysis of Pooled Data from Four Randomized Clinical Trials
BackgroundAdults aged â„ 60 years are often underrepresented in atopic dermatitis (AD) clinical trials; age-related comorbidities may impact treatment efficacy and safety.ObjectiveThe aim was to report dupilumab efficacy and safety in patients aged â„ 60 years with moderate-to-severe AD.MethodsData were pooled from four randomized, placebo-controlled dupilumab trials of patients with moderate-to-severe AD (LIBERTY AD SOLO 1 and 2, LIBERTY AD CAFĂ, and LIBERTY AD CHRONOS) and stratified by age (< 60 [N = 2261] and â„ 60 [N = 183] years). Patients received dupilumab 300 mg every week (qw) or every 2 weeks (q2w), or placebo with/without topical corticosteroids. Post hoc efficacy at week 16 was examined using broad categorical and continuous assessments of skin lesions, symptoms, biomarkers, and quality of life. Safety was also assessed.ResultsIn the â„ 60-year-old group at week 16, a greater proportion of dupilumab-treated patients achieved an Investigator's Global Assessment score of 0/1 (q2w: 44.4%; qw: 39.7%) and 75% improvement in Eczema Area and Severity Index (63.0%; 61.6%) versus placebo (7.1% and 14.3%, respectively; P < 0.0001). Type 2 inflammation biomarkers (immunoglobulin E and thymus and activation-regulated chemokine) were also significantly reduced in dupilumab- versus placebo-treated patients (P < 0.01). Results were similar in the < 60-year-old group. The exposure-adjusted incidences of adverse events in dupilumab-treated patients were generally similar to those receiving placebo, with numerically fewer treatment-emergent adverse events in the dupilumab-treated â„ 60-year-old group versus placebo.LimitationsThere were fewer patients in the â„ 60-year-old group; post hoc analyses.ConclusionDupilumab improved AD signs and symptoms in patients aged â„ 60 years; results were comparable to those in patients aged < 60 years. Safety was consistent with the known dupilumab safety profile.Trial registrationClinicalTrials.gov: NCT02277743, NCT02277769, NCT02755649, NCT02260986. Does dupilumab benefit adults aged 60 years and older with moderate-to-severe atopic dermatitis?(MP4 20,787 KB)
Efficacy and Safety of Dupilumab Maintained in Adults â„ 60 Years of Age with Moderate-to-Severe Atopic Dermatitis: Analysis of Pooled Data from Four Randomized Clinical Trials
BACKGROUND: Adults aged â„ 60 years are often underrepresented in atopic dermatitis (AD) clinical trials; age-related comorbidities may impact treatment efficacy and safety. OBJECTIVE: The aim was to report dupilumab efficacy and safety in patients aged â„ 60 years with moderate-to-severe AD. METHODS: Data were pooled from four randomized, placebo-controlled dupilumab trials of patients with moderate-to-severe AD (LIBERTY AD SOLO 1 and 2, LIBERTY AD CAFĂ, and LIBERTY AD CHRONOS) and stratified by age (\u3c 60 [N = 2261] and â„ 60 [N = 183] years). Patients received dupilumab 300 mg every week (qw) or every 2 weeks (q2w), or placebo with/without topical corticosteroids. Post hoc efficacy at week 16 was examined using broad categorical and continuous assessments of skin lesions, symptoms, biomarkers, and quality of life. Safety was also assessed. RESULTS: In the â„ 60-year-old group at week 16, a greater proportion of dupilumab-treated patients achieved an Investigator\u27s Global Assessment score of 0/1 (q2w: 44.4%; qw: 39.7%) and 75% improvement in Eczema Area and Severity Index (63.0%; 61.6%) versus placebo (7.1% and 14.3%, respectively; P \u3c 0.0001). Type 2 inflammation biomarkers (immunoglobulin E and thymus and activation-regulated chemokine) were also significantly reduced in dupilumab- versus placebo-treated patients (P \u3c 0.01). Results were similar in the \u3c 60-year-old group. The exposure-adjusted incidences of adverse events in dupilumab-treated patients were generally similar to those receiving placebo, with numerically fewer treatment-emergent adverse events in the dupilumab-treated â„ 60-year-old group versus placebo. LIMITATIONS: There were fewer patients in the â„ 60-year-old group; post hoc analyses. CONCLUSION: Dupilumab improved AD signs and symptoms in patients aged â„ 60 years; results were comparable to those in patients aged \u3c 60 years. Safety was consistent with the known dupilumab safety profile. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02277743, NCT02277769, NCT02755649, NCT02260986. Does dupilumab benefit adults aged 60 years and older with moderate-to-severe atopic dermatitis?(MP4 20,787 KB)