On the robustness of the Hβ\beta Lick index as a cosmic clock in passive early-type galaxies

We examine the H$\beta$ Lick index in a sample of $\sim 24000$ massive ($\rm log(M/M_{\odot})>10.75$) and passive early-type galaxies extracted from SDSS at z<0.3, in order to assess the reliability of this index to constrain the epoch of formation and age evolution of these systems. We further investigate the possibility of exploiting this index as "cosmic chronometer", i.e. to derive the Hubble parameter from its differential evolution with redshift, hence constraining cosmological models independently of other probes. We find that the H$\beta$ strength increases with redshift as expected in passive evolution models, and shows at each redshift weaker values in more massive galaxies. However, a detailed comparison of the observed index with the predictions of stellar population synthesis models highlights a significant tension, with the observed index being systematically lower than expected. By analyzing the stacked spectra, we find a weak [NII]$\lambda6584$ emission line (not detectable in the single spectra) which anti-correlates with the mass, that can be interpreted as a hint of the presence of ionized gas. We estimated the correction of the H$\beta$ index by the residual emission component exploiting different approaches, but find it very uncertain and model-dependent. We conclude that, while the qualitative trends of the observed H$\beta$-z relations are consistent with the expected passive and downsizing scenario, the possible presence of ionized gas even in the most massive and passive galaxies prevents to use this index for a quantitative estimate of the age evolution and for cosmological applications.Comment: 20 pages, 11 figures, 1 table. Accepted for publication in MNRAS Main Journa

Two-Face(s): ionized and neutral gas winds in the local Universe

We present a comprehensive study of the Na I $\lambda$5890, 5895 (Na I D) resonant lines in the Sloan Digital Sky Survey (SDSS, DR7) spectroscopic sample to look for neutral gas outflows in the local galaxies. Individual galaxy spectra are stacked in bins of M${\star}$ and SFR to investigate the dependence of galactic wind occurrence and velocity as a function of the galaxy position in the SFR-$M{\star}$ plane. In massive galaxies at the high SFR tail we find evidence of a significant blue-shifted Na I D absorption, which we interpret as evidence of neutral outflowing gas. The occurrence of the blue-shifted absorption is observed at the same significance for purely SF galaxies, AGN and composite systems at fixed SFR. In all classes of objects the blue-shift is the largest and the Na I D equivalent width the smallest for face-on galaxies while the absorption feature is at the systemic velocity for edge-on systems. This indicates that the neutral outflow is mostly perpendicular or biconical with respect to the galactic disk. We also compare the kinematics of the neutral gas with the ionized gas phase as traced by the [OIII]$\lambda$5007, H$\alpha$, [NII]$\lambda6548$ and [NII]$\lambda6584$ emission lines. Differently for the neutral gas phase, all the emission lines show evidence of perturbed kinematics only in galaxies with a significant level of nuclear activity and, they are independent from the disk inclination. In conclusion, we find that, in the local Universe, galactic winds show two faces which are related to two different ejection mechanisms, namely the neutral outflowing gas phase related to the SF activity along the galaxy disk and the ionized phase related to the AGN feedback. In both the neutral and ionized gas phases, the observed wind velocities suggest that the outflowing gas remains bound to the galaxy with no definitive effect on the gas reservoir.Comment: Accepted to A&A, 13 pages, 9 figure

Identifying the lights position in photometric stereo under unknown lighting

Reconstructing the 3D shape of an object from a set of images is a classical problem in Computer Vision. Photometric stereo is one of the possible approaches. It stands on the assumption that the object is observed from a fixed point of view under different lighting conditions. The traditional approach requires that the position of the light sources is accurately known. It has been proved that the lights position can be estimated directly from the data, when at least 6 images of the observed object are available. In this paper, we give a Matlab implementation of the algorithm for solving the photometric stereo problem under unknown lighting, and propose a simple shooting technique to solve the bas-relief ambiguity.Comment: new versio

Experiments and modeling of the growth of C. sorokiniana in lab batch and BIOCOIL photobioreactors for lipid production

A novel mathematical model for the quantitative assessment of the effect of dissolved nitrogen on the autotrophic batch-growth and lipid accumulation of C. sorokiniana, is proposed in this work. Model results have been validated through comparison with suitable experimental data performed in lab photobioreactors. Further experiments have been then performed using a BIOCOIL operated in fed-batch mode. The experimental results have been successfully predicted through the proposed model. Therefore, the model might represent a first step toward the development of a tool for the scale-up and optimization of the operating conditions of BIOCOIL photobioreactors. Furthermore, the fatty acid methyl esters obtained by transesterification of lipids extracted from C. sorokiniana, have been analysed in view of the assessment of their usability for producing biofuels. Subsequently, on the basis of the fatty acids profile, a wide range of biodiesel fuel properties have been predicted through suitable software

Fabrication of Flexible Double-Gate Organic Thin Film Transistor For Tactile Applications

In this work, the development of a flexible Double-Gate (DG) organic thin film transistor (DG-OTFT), and its employment is reported for the realization of multimodal tactile sensors. Due to the self-encapsulation of the stacked DG architecture, highly stable organic transistors are obtained that show almost negligible degradation after 6 months. Moreover, such configuration is also very useful for the development of sensing devices. In the case, one of the two gates is used to bias and set the working point of the devices, whereas the second one is connected to a polyvinylidene fluoride(PVDF)-capacitor, a pyro/piezoelectric material. It is demonstrated that the charge displacement induced by the PVDF capacitor due to an applied external pressure or due to a temperature variation led to a reproducible variation of the device's output current. Using this approach high-performing multimodal tactile sensors are obtained with sensitivity to up to 241 nA N-1 and 442 nA degrees C-1 respectively.Here, a flexible Double-Gate (DG) organic thin film transistor (DG-OTFT) and its employment as multimodal tactile sensors are reported. Due to its self-encapsulation given by the stacked DG architecture, the organic transistors present highly stable performances with almost negligible degradation after 6 months. Moreover, such configuration allows the development of a highly sensitive tactile sensor for artificial skin applications. imag

Field sampling of soil pore water to evaluate the mobile fraction of trace elements in the Iglesiente area (SW Sardinia, Italy)

Field soil pore water monitoring was applied in a highly heavy-metal contaminated area in SW Sardinia, Italy, as a direct, realistic measure of heavy metal mobility. The main chemistry of pore waters well reflects the local characteristics of soils, ranging from Ca-SO4 to (Ca)Mg-HCO3 to Ca(Na)-SO4(Cl), with a wide range of conductivity. The mobility of Zn and Pb is apparently controlled by equilibrium with minerals such as hydrozincite or smithsonite, and cerussite, respectively. These results allow a correct estimate of the actual environmental risk associated with the presence of heavy metals in soils, and may serve as a supporting tool for phytoremediation planning

Genetics, odor perception and food liking: The intriguing role of cinnamon

Humans use a repertoire of > 400 olfactory receptors (ORs) to perceive odorants. The sense of smell is a complex trait whereby genetics and environmental factors interplay. To date, still little is known regarding the genetics of smell, even though the high genetic variability of ORs genes has already been demonstrated. Recently a significant association between cinnamon odorant recognition and the rs317787 polymorphism, located in a cluster of OR genes, has been described. Based on this data, here, we replicated the effect of the same variant (rs317787) on cinnamon odorant identification as well as looked at any possible association with liking for wine whose bouquet frequently smells of cinnamon. Our analysis in a cohort of individuals from two Italian genetic isolates confirmed that rs317787-T allele is associated with an improved cinnamon detection (p-value 5.18 7 10 1206, n = 971) but also with a greater liking for red wine (p-value 0.017, n = 2374). Present results further confirm the association of rs31778 SNP and cinnamon odorants detection and provide additional details about the role of the ORs genes in food liking. Overall, our work contributes to better deciphering the genetic basis of smell and food liking aimed at a more in-depth elucidation of the role of the ORs genes

Remarks on ISRU and ISFR Technologies for Manned Missions on Moon and Mars

Space colonization and exploitation of extra-terrestrial natural resources could help humanity in facing various Earth problems. In this regard, production of energy and materials starting from Moon and Mars natural resources as well as the transportation of humans in space could be considered the long term remedy to issues such as overpopulation, depletion of fossil fuels, climate change as well as reduction of available natural resources. Along theses lines, two recently filed patents related to use of novel technologies for the in situ exploitation of natural resources available on Moon and Mars have been developed

Longitudinal and azimuthal evolution of two-particle transverse momentum correlations in Pb–Pb collisions at sNN=2.76TeV

This paper presents the first measurements of the charge independent (CI) and charge dependent (CD) two-particle transverse momentum correlators G2CI and G2CD in Pb–Pb collisions at sNN=2.76TeV by the ALICE collaboration. The two-particle transverse momentum correlator G2 was introduced as a measure of the momentum current transfer between neighboring system cells. The correlators are measured as a function of pair separation in pseudorapidity (Δη) and azimuth (Δφ) and as a function of collision centrality. From peripheral to central collisions, the correlator G2CI exhibits a longitudinal broadening while undergoing a monotonic azimuthal narrowing. By contrast, G2CD exhibits a narrowing along both dimensions. These features are not reproduced by models such as HIJING and AMPT. However, the observed narrowing of the correlators from peripheral to central collisions is expected to result from the stronger transverse flow profiles produced in more central collisions and the longitudinal broadening is predicted to be sensitive to momentum currents and the shear viscosity per unit of entropy density η/s of the matter produced in the collisions. The observed broadening is found to be consistent with the hypothesized lower bound of η/s and is in qualitative agreement with values obtained from anisotropic flow measurements

The production of FAHFA is enhanced when Haematococcus pluvialis is grown in CO2

Microalgae are considered as a potential source of bioactive compounds to be used in different fields including food and pharmaceutical industry. In this context, fatty acid esters of hydroxy-fatty acids (FAHFA) are emerging as a new class of compounds with anti-inflammatory and anti-diabetic properties. An existing gap in the field of algal research is the limited knowledge regarding the production of these compounds. Our research questions aimed to determine whether the microalga H. pluvialis can synthesize FAHFA and whether the production levels of these compounds are increased when cultivated in a CO2-rich environment. To answer these questions, we used a LC-QTOF/MS method for the characterization of FAHFA produced by H. pluvialis while an LC-MS/MS method was used for their quantitation. The cultivation conditions of H. pluvialis, which include the utilization of CO2, can result in a 10–50-fold increase in FAHFA production