High-spin states in 212Po above the α-decaying (18+) isomer

The nucleus Po has been produced through the fragmentation of a U primary beam at 1 GeV/nucleon at GSI, separated with the FRagment Separator, FRS, and studied via isomer γ-decay spectroscopy with the RISING setup. Two delayed previously unknown γ rays have been observed. One has been attributed to the E3 decay of a 21 isomeric state feeding the α-emitting 45-s (18) high-spin isomer. The other γ-ray line has been assigned to the decay of a higher-lying 23 metastable state. These are the first observations of high-spin states above the Po (18) isomer, by virtue of the selectivity obtained via ion-by-ion identification of U fragmentation products. Comparison with shell-model calculations points to shortfalls in the nuclear interactions involving high-j proton and neutron orbitals, to which the region around Z∼100 is sensitive.This work was partially supported by the Ministry of Science, and Generalitat Valenciana, Spain, under the Grants SEV-2014-0398, FPA2017-84756-C4, PID2019-104714GB-C21, PROMETEO/2019/005 and by the EU FEDER funds. The support of the UK STFC, of the Swedish Research Council under Contract No. 2008-4240 and No. 2016-3969 and of the DFG (EXC 153) is also acknowledged. The experimental activity has been partially supported by the EU under the FP6-Integrated Infras-tructure Initiative EURONS, Contract No. RII3-CT-2004-506065 and FP7-Integrated Infrastructure Initiative ENSAR, Grant No. 262010

Cosmic acceleration and phantom crossing in f(T)f(T)-gravity

In this paper, we propose two new models in $f(T)$ gravity to realize universe acceleration and phantom crossing due to dark torsion in the formalism. The model parameters are constrained and the observational test are discussed. The best fit results favors an accelerating universe with possible phantom crossing in the near past or future followed respectively by matter and radiation dominated era.Comment: 20 pages, 18 figures, Will appear in Astrophys Space Sc

<i>Euclid</i>: Early Release Observations – Deep anatomy of nearby galaxies

Euclid is poised to make significant advances in the study of nearby galaxies in the Local Universe. Here we present a first look at six galaxies observed for the Nearby Galaxy Showcase as part of the Euclid Early Release Observations acquired between August and November, 2023. These targets, three dwarf galaxies (Holmberg II, IC 10, and NGC 6822) and three spirals (IC 342, NGC 2403, and NGC 6744), range in distance from about 0.5 Mpc to 8.8 Mpc. We first assess the surface brightness depths in the stacked Euclid images, and confirm previous estimates in 100 arcsec 2 regions for Visible Camera (VIS) of 1σ limits of 30.5 mag arcsec -2 , but find deeper than previous estimates for Near-Infrared Spectrometer and Photometer (NISP) with 1σ = 29.2-29.4mag arcsec -2 . By combining Euclid HE , YE , and IE into RGB images, we illustrate the large field of view (FoV) covered by a single reference observing sequence (ROS), together with exquisite detail on scales of Euclid is consistent with what is expected for galaxy colors according to stellar synthesis models. We perform standard source-selection techniques for stellar photometry, and find approximately 1.3 million stars across the six galaxy fields. After subtracting foreground stars and background galaxies, and applying a color and magnitude selection, we extract stellar populations of different ages for the six galaxies. The resolved stellar photometry obtained with Euclid allows us to constrain the star-formation histories of these galaxies, which we do by disentangling the distributions of young stars and asymptotic giant branch and red giant branch stellar populations. We finally examine two galaxies individually for surrounding systems of dwarf galaxy satellites and globular cluster populations. Our analysis of the ensemble of dwarf satellites around NGC 6744 recovers all the previously known dwarf satellites within the Euclid FoV, and also confirms the satellite nature of a previously identified candidate, dw1909m6341, a nucleated dwarf spheroidal at the end of a spiral arm. Our new census of the globular clusters around NGC 2403 yields nine new star-cluster candidates, eight of which exhibit colors indicative of evolved stellar populations. In summary, our first investigation of six “showcase” galaxies demonstrates that Euclid is a powerful probe of stellar structure and stellar populations in nearby galaxies, and will provide vastly improved statistics on dwarf satellite systems and extragalactic globular clusters in the local Universe, among many other exciting results

Euclid Quick Data Release (Q1). Extending the quest for little red dots to z<4

Recent observations with the James Webb Space Telescope (JWST) have revealed an interesting population of sources with a compact morphology and a characteristic v-shaped continuum, namely blue at a rest frame łambda<4000,Å and red at longer wavelengths. The nature of these sources, which are called little red dots (LRDs), is still highly debated because it is unclear whether they host active galactic nuclei (AGNs) and their number seems to drop drastically at z<4. We took advantage of the $63,̊m covered by the quick Euclid Quick Data Release (Q1) to extend the search for LRDs to brighter magnitudes and lower redshifts than what was possible with JWST. This is fundamental for a broader view of the evolution of this peculiar galaxy population. The selection was performed by fitting the available photometric data (Euclid, the Spitzer Infrared Array Camera (IRAC), and ground-based griz data) with two power laws to retrieve the rest-frame optical and UV slopes consistently over a wide redshift range (i.e. z<7.6). We then excluded extended objects and possible line emitters and inspected the data visually to remove any imaging artefacts. The final selection included 3341 LRD candidates from z=0.33 to z=3.6, 29 of which were also detected in IRAC. The resulting rest-frame UV luminosity function, in contrast with previous JWST studies, shows that the number density of LRD candidates increases from high redshift to z=1.5--$2.5$ and decreases at even lower redshifts. The subsample of more robust LRD candidates that are also detected with IRAC show a weaker evolution, however, which is affected by low statistics and limited by the IRAC resolution. The comparison with previous quasar UV luminosity functions shows that LRDs are not the dominant AGN population at z<4 and M_ ̊m UV <-21. Follow-up studies of these LRD candidates are pivotal to confirm their nature, probe their physical properties, and determine whether they are compatible with JWST sources because the different spatial resolution and wavelength coverage of Euclid and JWST might select different samples of compact sources

XXXVII Congresso Nazionale AIEOP, Bari, 20-22 maggio 2012 - Abstracts

<strong>Book of abstracts - XXXVII Congresso Nazionale AIEOP, Bari, 20-22 maggio 2012</strong

Levels of Enzymatic Antioxidants Activities in Mononuclear Cells and Skin Reactivity to Sodium Dodecyl Sulphate

Chemical irritants are able to produce several biological modifications of the skin, including the direct or indirect production of cytokines and reactive oxygen species leading to an inflammatory reaction. This report examines the existence of a possible correlation between the skin sensitivity to the irritant sodium dodecyl sulphate (SDS) and the activity of the enzymatic antioxidants. In twenty-three healthy subjects the evaluation of the epidermal and peripheral blood mononuclear cells (PBMCs) activities of superoxide Dismutase (SOD) and Catalase (Cat) demonstrate a significant correlation (r= 0,85 and p&lt; 0,005 for SOD, and r= 0,87 and p&lt; 0,0001 for Cat). Based on this result, on a further group of normal subjects (n=13) we studied the link between the threshold dose of skin reactivity to SDS and the activities of the enzymatic antioxidants in PBMCs. The degree of skin modification induced by SDS, applied at different concentrations for 24 hrs, was determined by means of Trans Epidermal Water Loss (TEWL), Erythemal Index or by Visual Score (VS). The minimal dose of the irritant capable of inducing skin modifications, was significantly correlated with SOD (r=0,77) and Cat (r=0,81) activities in PBMCs, and the modification of TEWL or EI were inversely correlated with levels of antioxidants in PBMCs (r=−0,62 for SOD and r=−0,66 for Cat). Our results indicate that the skin reactivity to irritants can be modulated by the levels of antioxidants, and suggest a possible therapeutical approach in preventing irritant contact dermatitis. </jats:p

Peering into the Past

In the last few decades, cosmological measurements have reached an unprecedented level of precision, and cosmology is now on the threshold of a new era of observational evidence. In the next future, a vast number of telescopes, satellites and surveys will provide us with accurate, multi-wavelength data that will allow us to investigate the fundaments of our theoretical model of the Universe. Here, we depict, with some useful example, how such a gaze to the deepest cosmos could help in better understanding the laws of gravity and perhaps detecting departures from GR. Specifically, we show recent constraints on well-known alternative gravity theories from some of these next-generation instruments

Chemotactic effect of prorenin on human aortic smooth muscle cells: a novel function of the prorenin receptor

The discovery of a specific prorenin receptor has opened to a possible biological function of prorenin independently from angiotensin I production. In the present study we show that prorenin receptor is expressed in normal human vessels (mammary arteries and saphenous veins) and in cultured human aortic smooth muscle cells, by western blotting, quantitative real time PCR and immunocytochemistry analysis. Prorenin (10 nmol/L) exerted a 3 fold induction of smooth muscle cell migration assessed by Boyden chamber chemotaxis assay after 6h stimulation and a 30% increase of smooth muscle cell random motility determined by video microscopy. The prorenin decoy peptide (10 \uf06dmol/L) almost completely inhibited smooth muscle cell migration in response to prorenin, while no effect was observed with a scrambled peptide. Knock down of prorenin receptor by small interfering RNA completely affected the migratory response of smooth muscle cells to prorenin. Prorenin increased focal adhesion size (+42.8\ub123.0%) and RhoA activation (+15.0\ub15.0%) after 10 minutes stimulation associated with cleavage of the focal adhesion kinase (pp125FAK) at 60 minutes. The generation of a 50kDa fragment of pp125FAK was suppressed by the calpain inhibitor ALLN (100 \uf06dmol/L), which also inhibited smooth muscle cell migration in response to prorenin. Thus, in the present report we show that prorenin is expressed in human vessels and in cultured smooth muscle cells where it exerts a chemotactic action. This effect is associated with a profound cytoskeleton and focal adhesion re-organization, RhoA activation and calpain-mediated pp125FAK cleavage