449 research outputs found
Large Binocular Telescope view of the atmosphere of GJ1214b
The atmospheric composition and vertical structure of the super-Earth GJ1214b
has been a subject of debate since its discovery in 2009. Recent studies have
indicated that high-altitude clouds might mask the lower layers. However, some
data points that were gathered at different times and facilities do not fit
this picture, probably because of a combination of stellar activity and
systematic errors. We observed two transits of GJ1214b with the Large Binocular
Camera, the dual-channel camera at the Large Binocular Telescope. For the first
time, we simultaneously measured the relative planetary radius
at blue and red optical wavelengths (), thus
constraining the Rayleigh scattering on GJ1214b after correcting for stellar
activity effects. To the same purpose, a long-term photometric follow-up of the
host star was carried out with WiFSIP at STELLA, revealing a rotational period
that is significantly longer than previously reported. Our new unbiased
estimates of yield a flat transmission spectrum extending to shorter
wavelengths, thus confirming the cloudy atmosphere scenario for GJ1214b.Comment: 11 pages, 5 figures, 3 tables. Published in A&A. Minor changes to
reflect the published versio
Evidence of orbital reconstruction at interfaces in La0.67Sr0.33MnO3 films
Electronic properties of transition metal oxides at interfaces are influenced
by strain, electric polarization and oxygen diffusion. Linear dichroism (LD)
x-ray absorption, diffraction, transport and magnetization on thin
La0.7Sr0.3MnO3 films, allow identification of a peculiar universal interface
effect. We report the LD signature of preferential 3d-eg(3z2-r2) occupation at
the interface, suppressing the double exchange mechanism. This surface orbital
reconstruction is opposite of that favored by residual strain and independent
of dipolar fields, chemical nature of the substrate and capping.Comment: 13 pages, 5 figure
Activation of NF-kappaB/Rel transcription factors in human primary peripheral blood mononuclear cells by interleukin 7.
Pathways that regulate the activation of NF-kappaB/Rel transcription factors are known to include signaling through a number of cytokine receptors. Interleukin 7 (IL-7), produced by bone marrow and other stromal cells, is a key factor for differentiation and survival in the lymphoid and other compartments. We found that human recombinant IL-7 induced NF-kappaB/Rel activation, analyzed by electrophoretic mobility shift assay (EMSA), in human peripheral blood T lymphocytes from healthy donors. Induced complexes included p65 and p50 NF-kappaB/Rel subunits. These results demonstrate for the first time that IL-7 can participate in signaling leading to NF-kappaB/Rel activation
Practice Recommendations for Diagnosis and Treatment of the Most Common Forms of Secondary Hypertension
The vast majority of hypertensive patients are never sought for a cause of their high blood pressure, i.e. for a \u2018secondary\u2019 form of arterial hypertension. This under detection explains why only a tiny percentage of hypertensive patients are ultimately diagnosed with a secondary form of arterial hypertension. The prevalence of these forms is, therefore, markedly underestimated, although, they can involve as many as one-third of the cases among referred patients and up to half of those with difficult to treat hypertension. The early detection of a secondary form is crucial, because if diagnosed in a timely manner, these forms can be cured at long-term, and even when cure cannot be achieved, their diagnosis provides a better control of high blood pressure, and allows prevention of hypertension-mediated organ damage, and related cardiovascular complications. Enormous progress has been made in the understanding, diagnostic\ua0work-up, and management of secondary hypertension in the last decades. The\ua0aim of this minireview is, therefore, to provide updated concise information on the screening, diagnosis, and management of the most common forms, including primary aldosteronism, renovascular hypertension, pheochromocytoma and paraganglioma, Cushing\u2019s syndrome, and obstructive sleep apnea
Analysis of time-profiles with in-beam PET monitoring in charged particle therapy
Background: Treatment verification with PET imaging in charged particle
therapy is conventionally done by comparing measurements of spatial
distributions with Monte Carlo (MC) predictions. However, decay curves can
provide additional independent information about the treatment and the
irradiated tissue. Most studies performed so far focus on long time intervals.
Here we investigate the reliability of MC predictions of space and time (decay
rate) profiles shortly after irradiation, and we show how the decay rates can
give an indication about the elements of which the phantom is made up.
Methods and Materials: Various phantoms were irradiated in clinical and
near-clinical conditions at the Cyclotron Centre of the Bronowice proton
therapy centre. PET data were acquired with a planar 16x16 cm PET system.
MC simulations of particle interactions and photon propagation in the phantoms
were performed using the FLUKA code. The analysis included a comparison between
experimental data and MC simulations of space and time profiles, as well as a
fitting procedure to obtain the various isotope contributions in the phantoms.
Results and conclusions: There was a good agreement between data and MC
predictions in 1-dimensional space and decay rate distributions. The fractions
of C, O and C that were obtained by fitting the decay
rates with multiple simple exponentials generally agreed well with the MC
expectations. We found a small excess of C in data compared to what was
predicted in MC, which was clear especially in the PE phantom.Comment: 9 pages, 5 figures, 1 table. Proceedings of the 20th International
Workshop on Radiation Imaging Detectors (iWorid2018), 24-28 June 2018,
Sundsvall, Swede
Enhancement of cytosine arabinoside-induced apoptosis in human myeloblastic leukemia cells by NFkB/Rel- specific decoy oligodeoxynucleotides
The activity of NF-kB/Rel nuclear factors is known to inhibit
apoptosis in various cell types. We investigated whether the
subtraction of NF-kB/Rel activity influenced the response of
11 AML (M1, M2 and M4) patients’ cells to AraC. To this
end we used a phosphorothioate double-stranded decoy oligodeoxynucleotide
(ODN) carrying the NF-kB/Rel- consensus
sequence. Cell incubation with this ODN, but not its
mutated (scrambled) form used as a control, resulted in
abating the NF-kB/Rel nuclear levels in these cells, as verified
by electrophoretic mobility shift assay (EMSA) of cells’
nuclear extracts. We incubated the leukemic cells with AraC
(32 or 1 mM), in either the absence or presence of the decoy or the scrambled ODN, and analyzed cell apoptosis. The
spontaneous cell apoptosis detectable in the absence of
AraC (,25%) was not modulated by the oligonucleotide
presence in cell cultures. On the other hand, in 10 of the 11
samples tested, the decoy kB, but not the scrambled ODN
significantly (P ,0.01 in a Student’s t test) enhanced cell
apoptotic response to AraC. Such an effect was particularly
remarkable at low AraC doses (1 mM). These findings indicate
that NF-kB/Rel activity influences response to AraC in
human primary myeloblastic cells, and suggests that the
inhibition of NF-kB/Rel factors can improve the effect of
chemotherapy in AM
Electronic Transitions in Strained SmNiO_3 Thin Films
Nickelates are known for their metal to insulator transition (MIT) and an
unusual magnetic ordering, occurring at T=T_N\'eel. Here, we investigate thin
films of SmNiO_3 subjected to different levels of epitaxial strain. We find
that the original bulk behavior (T_N\'eel<T_MI) is strongly affected by
applying compressive strain to the films. For small compressive strains, a
regime where T_N\'eel=T_MI is achieved, the paramagnetic insulating phase
characteristic of the bulk compound is suppressed and the MIT becomes 1st
order. Further increasing the in-plane compression of the SmNiO_3 lattice leads
to the stabilization of a single metallic paramagnetic phase
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