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The Abundance of S-Process Elements: Temporal and Spatial Trends from Open Cluster Observations
Spectroscopic observations of stars belonging to open clusters, with well-determined ages and distances, are a unique tool for constraining stellar evolution, nucleosynthesis, mixing processes, and, ultimately, Galactic chemical evolution. Abundances of slow (s) process neutron capture elements in stars that retain their initial surface composition open a window into the processes that generated them. In particular, they give us information on their main site of production, i.e., the low-and intermediate-mass Asymptotic Giant Branch (AGB) stars. In the present work, we review some observational results obtained during the last decade that contributed to a better understanding of the AGB phase: the growth of s-process abundances at recent epochs, i.e., in the youngest stellar populations; the different relations between age and [s/Fe] in distinct regions of the disc; and finally the use of s-process abundances combined with those of α elements, [s/α], to estimate stellar ages. We revise some implications that these observations had both on stellar and Galactic evolution, and on our ability to infer stellar ages
Prognostic role of clusterin in resected adenocarcinomas of the lung
Rationale
Clusterin expression may change in various human malignancies, including lung cancer. Patients with resectable non-small cell lung cancer (NSCLC), including adenocarcinoma, have a poor prognosis, with a relapse rate of 30\u201350% within 5 years. Nuclear factor kB (Nf-kB) is an intracellular protein involved in the initiation and progression of several human cancers, including the lung.
Objectives
We investigate the role of clusterin and Nf-kB expression in predicting the prognosis of patients with early-stage surgically resected adenocarcinoma of the lung.
Findings
The level of clusterin gradually decreased from well-differentiated to poorly differentiated adenocarcinomas. Clusterin expression was significantly higher in patients with low-grade adenocarcinoma, in early-stage disease and in women. Clusterin expression was inversely related to relapse and survival in both univariate and multivariate analyses. Finally, we observed an inverse correlation between Nf-kB and clusterin.
Conclusions
Clusterin expression represents an independent prognostic factor in surgically resected lung adenocarcinoma and was proven to be a useful biomarker for fewer relapses and longer survival in patients in the early stage of disease. The inverse correlation between Nf-kB and clusterin expression confirm the previously reported role of clusterin as potent down regulator of Nf-kB
Measuring, modelling and managing gully erosion at large scales: A state of the art
Soil erosion is generally recognized as the dominant process of land degradation. The formation and expansion of gullies is often a highly significant process of soil erosion. However, our ability to assess and simulate gully erosion and its impacts remains very limited. This is especially so at regional to continental scales. As a result, gullying is often overlooked in policies and land and catchment management strategies. Nevertheless, significant progress has been made over the past decades. Based on a review of >590 scientific articles and policy documents, we provide a state-of-the-art on our ability to monitor, model and manage gully erosion at regional to continental scales. In this review we discuss the relevance and need of assessing gully erosion at regional to continental scales (Section 1); current methods to monitor gully erosion as well as pitfalls and opportunities to apply them at larger scales (section 2); field-based gully erosion research conducted in Europe and European Russia (section 3); model approaches to simulate gully erosion and its contribution to catchment sediment yields at large scales (section 4); data products that can be used for such simulations (section 5); and currently existing policy tools and needs to address the problem of gully erosion (section 6). Section 7 formulates a series of recommendations for further research and policy development, based on this review. While several of these sections have a strong focus on Europe, most of our findings and recommendations are of global significance.info:eu-repo/semantics/publishedVersio
ExoClock project: an open platform for monitoring the ephemerides of Ariel targets with contributions from the public
The Ariel mission will observe spectroscopically around 1000 exoplanets to further characterise their atmospheres. For the mission to be as efficient as possible, a good knowledge of the planets’ ephemerides is needed before its launch in 2028. While ephemerides for some planets are being refined on a per-case basis, an organised effort to collectively verify or update them when necessary does not exist. In this study, we introduce the ExoClock project, an open, integrated and interactive platform with the purpose of producing a confirmed list of ephemerides for the planets that will be observed by Ariel. The project has been developed in a manner to make the best use of all available resources: observations reported in the literature, observations from space instruments and, mainly, observations from ground-based telescopes, including both professional and amateur observatories. To facilitate inexperienced observers and at the same time achieve homogeneity in the results, we created data collection and validation protocols, educational material and easy to use interfaces, open to everyone. ExoClock was launched in September 2019 and now counts over 140 participants from more than 15 countries around the world. In this release, we report the results of observations obtained until the 15h of April 2020 for 120 Ariel candidate targets. In total, 632 observations were used to either verify or update the ephemerides of 84 planets. Additionally, we developed the Exoplanet Characterisation Catalogue (ECC), a catalogue built in a consistent way to assist the ephemeris refinement process. So far, the collaborative open framework of the ExoClock project has proven to be highly efficient in coordinating scientific efforts involving diverse audiences. Therefore, we believe that it is a paradigm that can be applied in the future for other research purposes, too
Acute diverticulitis management: evolving trends among Italian surgeons. A survey of the Italian Society of Colorectal Surgery (SICCR)
Acute diverticulitis (AD) is associated with relevant morbidity/mortality and is increasing worldwide, thus becoming a major issue for national health systems. AD may be challenging, as clinical relevance varies widely, ranging from asymptomatic picture to life-threatening conditions, with continuously evolving diagnostic tools, classifications, and management. A 33-item-questionnaire was administered to residents and surgeons to analyze the actual clinical practice and to verify the real spread of recent recommendations, also by stratifying surgeons by experience. CT-scan remains the mainstay of AD assessment, including cases presenting with recurrent mild episodes or women of child-bearing age. Outpatient management of mild AD is slowly gaining acceptance. A conservative management is preferred in non-severe cases with extradigestive air or small/non-radiologically drainable abscesses. In severe cases, a laparoscopic approach is preferred, with a non-negligible number of surgeons confident in performing emergency complex procedures. Surgeons are seemingly aware of several options during emergency surgery for AD, since the rate of Hartmann procedures does not exceed 50% in most environments and damage control surgery is spreading in life-threatening cases. Quality of life and history of complicated AD are the main indications for delayed colectomy, which is mostly performed avoiding the proximal vessel ligation, mobilizing the splenic flexure and performing a colorectal anastomosis. ICG is spreading to check anastomotic stumps' vascularization. Differences between the two experience groups were found about the type of investigation to exclude colon cancer (considering the experience only in terms of number of colectomies performed), the size of the peritoneal abscess to be drained, practice of damage control surgery and the attitude towards colovesical fistula
The commissioning of the CUORE experiment: the mini-tower run
CUORE is a ton-scale experiment approaching the data taking phase in Gran Sasso National Laboratory. Its primary goal is to search for the neutrinoless double-beta decay in 130Te using 988 crystals of tellurim dioxide. The crystals are operated as bolometers at about 10 mK taking advantage of one of the largest dilution cryostat ever built. Concluded in March 2016, the cryostat commissioning consisted in a sequence of cool down runs each one integrating new parts of the apparatus. The last run was performed with the fully configured cryostat and the thermal load at 4 K reached the impressive mass of about 14 tons. During that run the base temperature of 6.3 mK was reached and maintained for more than 70 days. An array of 8 crystals, called mini-tower, was used to check bolometers operation, readout electronics and DAQ. Results will be presented in terms of cooling power, electronic noise, energy resolution and preliminary background measurements
Results from the Cuore Experiment
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for neutrinoless double beta decay that has been able to reach the 1-ton scale. The detector consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers, each of them made of 52 crystals. The construction of the experiment was completed in August 2016 and the data taking started in spring 2017 after a period of commissioning and tests. In this work we present the neutrinoless double beta decay results of CUORE from examining a total TeO2 exposure of 86.3kg yr, characterized by an effective energy resolution of 7.7 keV FWHM and a background in the region of interest of 0.014 counts/ (keV kg yr). In this physics run, CUORE placed a lower limit on the decay half- life of neutrinoless double beta decay of 130Te > 1.3.1025 yr (90% C. L.). Moreover, an analysis of the background of the experiment is presented as well as the measurement of the 130Te 2vo3p decay with a resulting half- life of T2 2. [7.9 :- 0.1 (stat.) :- 0.2 (syst.)] x 10(20) yr which is the most precise measurement of the half- life and compatible with previous results
Status and prospects of discovery of 0νββ decay with the CUORE detector
In this contribution we present the achievements of the CUORE
experiment so far. It is the first tonne-scale bolometric detector and it is in stable
data taking since 2018. We reached to collect about 1800 kg×yr of exposure of
which more than 1ton×year have been analysed. The CUORE detector is meant
to search for the neutrinoless double β decay (0νββ) of the 130Te isotope. This is
a beyond Standard Model process which could establish the nature of the neutrino
to be Dirac or a Majorana particle. It is an alternative mode of the two-neutrinos
double β decay, a rare decay which have been precisely measured by CUORE in
the 130Te. We found no evidence of the 0νββ and we set a Bayesian lower limit
of 2.2×1025yr on its half-life. The expertise achieved by CUORE set a milestone
for any future bolometric detector, including CUPID, which is the planned next
generation experiment searching for 0νββ with scintillating bolometers
A first test of CUPID prototypal light detectors with NTD-Ge sensors in a pulse-tube cryostat
CUPID is a next-generation bolometric experiment aiming at searching for
neutrinoless double-beta decay with ~250 kg of isotopic mass of Mo. It
will operate at 10 mK in a cryostat currently hosting a similar-scale
bolometric array for the CUORE experiment at the Gran Sasso National Laboratory
(Italy). CUPID will be based on large-volume scintillating bolometers
consisting of Mo-enriched LiMoO crystals, facing thin
Ge-wafer-based bolometric light detectors. In the CUPID design, the detector
structure is novel and needs to be validated. In particular, the CUORE cryostat
presents a high level of mechanical vibrations due to the use of pulse tubes
and the effect of vibrations on the detector performance must be investigated.
In this paper we report the first test of the CUPID-design bolometric light
detectors with NTD-Ge sensors in a dilution refrigerator equipped with a pulse
tube in an above-ground lab. Light detectors are characterized in terms of
sensitivity, energy resolution, pulse time constants, and noise power spectrum.
Despite the challenging noisy environment due to pulse-tube-induced vibrations,
we demonstrate that all the four tested light detectors comply with the CUPID
goal in terms of intrinsic energy resolution of 100 eV RMS baseline noise.
Indeed, we have measured 70--90 eV RMS for the four devices, which show an
excellent reproducibility. We have also obtained outstanding energy resolutions
at the 356 keV line from a Ba source with one light detector achieving
0.71(5) keV FWHM, which is -- to our knowledge -- the best ever obtained when
compared to detectors of any technology in this energy range.Comment: Prepared for submission to JINST; 16 pages, 7 figures, and 1 tabl
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