Comparing carbon isotope composition of bulk wood and holocellulose fromQuercus cerris,Fraxinus ornusandPinus radiatatree rings

Tree-ring \u3b413C is widely employed in ecophysiological studies, because it represents an integrated proxy of the ratio between photosynthesis (A) and stomatal conductance (g), which expresses the intrinsic water use efficiency (iWUE), strongly affected by the environmental conditions experienced by the plant during its life span. Tree-ring \u3b413C also reflects long term variations of atmospheric CO2 concentration and of its carbon isotope composition, partly due to increasing anthropogenic emissions. Carbon isotope abundances in tree rings can be assessed on bulk wood as well as on wood biochemical components, wich show different \u3b413C values because of secondary discrimination during biosynthesis. We present the results of a comparison between \u3b413C values of bulk wood and holocellulose samples obtained from the last three (1999, 2000 and 2001) annual growth rings of two hardwood (Quercus cerris L. and Fraxinus ornus L. and one conifer (Pinus radiata D. Don, species. We found that 13C values differed significantly among tree species, both in the case of holocellulose and bulk wood, but only in the case of P. radiata bulk wood samples tend to provide more negative \u3b413C values than holocellulose, as reported in the literature. We suggest that, at least for the two hardwood species studied, bulk wood is a suitable material to work with for \u3b413C assessment, whilst in P. radiata holocellulose could provide a more stable and reliable index, when studying plant ecophysiological responses to changing environmental conditions

CHANTI: a Fast and Efficient Charged Particle Veto Detector for the NA62 Experiment at CERN

The design, construction and test of a charged particle detector made of scintillation counters read by Silicon Photomultipliers (SiPM) is described. The detector, which operates in vacuum and is used as a veto counter in the NA62 experiment at CERN, has a single channel time resolution of 1.14 ns, a spatial resolution of ~2.5 mm and an efficiency very close to 1 for penetrating charged particles

Computational approaches to shed light on molecular mechanisms in biological processes

Computational approaches based on Molecular Dynamics simulations, Quantum Mechanical methods and 3D Quantitative Structure-Activity Relationships were employed by computational chemistry groups at the University of Milano-Bicocca to study biological processes at the molecular level. The paper reports the methodologies adopted and the results obtained on Aryl hydrocarbon Receptor and homologous PAS proteins mechanisms, the properties of prion protein peptides, the reaction pathway of hydrogenase and peroxidase enzymes and the defibrillogenic activity of tetracyclines. © Springer-Verlag 2007

Ultra-deep GEMINI near-infrared observations of the bulge globular cluster NGC 6624

We used ultra-deep $J$ and $K_s$ images secured with the near-infrared GSAOI camera assisted by the multi-conjugate adaptive optics system GeMS at the GEMINI South Telescope in Chile, to obtain a ($K_s$, $J-K_s$) color-magnitude diagram (CMD) for the bulge globular cluster NGC 6624. We obtained the deepest and most accurate near-infrared CMD from the ground for this cluster, by reaching $K_s$ $\sim$ 21.5, approximately 8 magnitudes below the horizontal branch level. The entire extension of the Main Sequence (MS) is nicely sampled and at $K_s$ $\sim$ 20 we detected the so-called MS "knee" in a purely near-infrared CMD. By taking advantage of the exquisite quality of the data, we estimated the absolute age of NGC 6624 ($t_{age}$ = 12.0 $\pm$ 0.5 Gyr), which turns out to be in good agreement with previous studies in the literature. We also analyzed the luminosity and mass functions of MS stars down to M $\sim$ 0.45 M$_{\odot}$ finding evidence of a significant increase of low-mass stars at increasing distances from the cluster center. This is a clear signature of mass segregation, confirming that NGC 6624 is in an advanced stage of dynamical evolution.Comment: Accepted for publication by ApJ. 39 pages, 19 figures, 1 tabl

Prevalence of HBV-genotypes in immigrants affected by HBV-related chronic active hepatitis

BACKGROUND: The genetic heterogeneity of the HBV genome has been established and eight genotypes can be classified according to the criterion of >8% differences in the complete nucleotide sequence of the viral genome. AIMS: To evaluate the prevalence of HBV-infection in a population of immigrants and to determine in patients with detectable serum HBV-DNA the HBV-genotypes. METHODS: Between January 2005 and December 2005 a total of 556 immigrants were tested for HBsAg. In HBsAg positive patients the biochemical and virological activity of infection and the possible presence of co-infections (HCV, HDV, HIV) were evaluated. In patients with detectable serum HBV DNA, the HBV-genotype was determined by INNOLiPA. RESULTS: Among the 556 subjects tested, 60 (10.7%) resulted HBsAg positive. All were men, and 42 (70%) come from Africa, 10 (16.6%) from Asia and 9 (14.4%) from East-Europe. 28/60 (46.6%) patients presented normal ALT levels (<40 IU/L) and undetectable serum HBV DNA (<100 copies/mL in real-time PCR), while 32 (53.4%) patients had ALT levels above laboratory normal values and detectable serum HBV DNA. Genotype distribution was as follow: genotype E, 16 (50%), genotype D, 9 (28.1%), genotype A, 7 (21.9%). CONCLUSION: Our study evidences a moderate prevalence of HBV-infection in immigrants, particularly in sub-Saharan African people, and the potentiality of migratory flow in the introduction of genotype non-D hepatitis B virus, potentially characterized by a different natural history and, possibly, a different response to antiviral treatment

A panchromatic view of the bulge globular cluster NGC 6569

We used high-resolution optical HST/WFC3 and multi-conjugate adaptive optics assisted GEMINI GeMS/GSAOI observations in the near-infrared to investigate the physical properties of the globular cluster NGC 6569 in the Galactic bulge. We have obtained the deepest purely NIR color-magnitude diagram published so far for this cluster using ground-based observations, reaching $K_{s}$ $\approx$ 21.0 mag (two magnitudes below the main-sequence turn-off point). By combining the two datasets secured at two different epochs, we determined relative proper motions for a large sample of individual stars in the center of NGC 6569, allowing a robust selection of cluster member stars. Our proper motion analysis solidly demonstrates that, despite its relatively high metal content, NGC 6569 hosts some blue horizontal branch stars. A differential reddening map has been derived in the direction of the system, revealing a maximum color excess variation of about $\delta E(B-V)$ $\sim$ 0.12 mag in the available field of view. The absolute age of NGC 6569 has been determined for the first time. In agreement with the other few bulge globular clusters with available age estimates, NGC 6569 turns out to be old, with an age of about 12.8 Gyr, and a typical uncertainty of 0.8-1.0 Gyr.Comment: 25 pages, 16 Figures, 1 Table. Accepted for publication in Ap

Seroconversion and indolent course of COVID-19 in patients with multiple sclerosis treated with fingolimod and teriflunomide

Non applicale in quanto si tratta di di una Letter to the Edito

Prevalence of diabetes mellitus in newly diagnosed pulmonary tuberculosis in Beira, Mozambique

Introduction: Data regarding the association between diabetes mellitus (DM) and tuberculosis (TB) in Africa are scarce. DM screening among TB patients in Mozambique was carried out. Methods: The study was implemented from January to August 2016 in three Urban Health Centers in Beira, Mozambique and recruited adult (&gt;18 years) patients newly diagnosed with pulmonary TB. Results: Three hundred and one patients were enrolled (67.4%, males mean age 31.7(SD 11 years). Diabetes was diagnosed in only 3 patients (1%) and impaired glucose tolerance (IGT) in an additional 6 subjects (2%). Conclusion: A lower than expected prevalence of DM was observed, which could be explained by the lack of traditional risk factors for DM (overweight, age over 45 years, hypertension and smoking) in Mozambique

Digging for Relics of the Past: The Ancient and Obscured Bulge Globular Cluster NGC 6256

We used a set of moderately deep and high-resolution optical observations obtained with the Hubble Space Telescope to investigate the properties of the stellar population in the heavily obscured bulge globular cluster (GC) NGC 6256. The analysis of the color–magnitude diagram (CMD) revealed a stellar population with an extended blue horizontal branch severely affected by differential reddening, which was corrected, taking into account color excess variations up to δE(B − V) ~ 0.51. We implemented a Monte Carlo Markov Chain technique to perform the isochrone fitting of the observed CMD in order to derive the stellar age, the cluster distance, and the average color excess in the cluster direction. Using three different sets of isochrones we found that NGC 6256 is characterized by a very old stellar age around 13.0 Gyr, with a typical uncertainty of ~0.5 Gyr. We also found an average color excess of E(B − V) = 1.19 and a distance from the Sun of 6.8 kpc. We then derived the cluster gravitational center and measured its absolute proper motion using the Gaia-DR2 catalog. All this was used to back-integrate the cluster orbit in a Galaxy-like potential and measure its integrals of motion. It turned out that NGC 6256 is currently in a low-eccentricity orbit entirely confined within the bulge and its integrals of motion are fully compatible with a cluster purely belonging to the Galaxy native GC population. All these pieces of evidence suggest that NGC 6256 is an extremely old relic of the past history of the Galaxy, formed during the very first stages of its assembly

The Saccharomyces cerevisiae SDA1 gene is required for actin cytoskeleton organization and cell cycle progression

The organization of the actin cytoskeleton is essential for several cellular processes. Here we report the characterization of a Saccharomyces cerevisiae novel gene, SDA1, encoding a highly conserved protein, which is essential for cell viability and is localized in the nucleus. Depletion or inactivation of Sda1 cause cell cycle arrest in G 1 by blocking both budding and DNA replication, without loss of viability. Furthermore, sda1-1 temperature-sensitive mutant cells arrest at the non-permissive temperature mostly without detectable structures of polymerized actin, although a normal actin protein level is maintained, indicating that Sda1 is required for proper organization of the actin cytoskeleton. To our knowledge, this is the first mutation shown to cause such a phenotype. Recovery of Sda1 activity restores proper assembly of actin structures, as well as budding and DNA replication. Furthermore we show that direct actin perturbation, either in sda1-1 or in cdc28-13 cells released from G 1 block, prevents recovery of budding and DNA replication. We also show that the block in G 1 caused by loss of Sda1 function is independent of Swe1. Altogether our results suggest that disruption of F-actin structure can block cell cycle progression in G 1 and that Sda1 is involved in the control of the actin cytoskeleton