Dust emission and star formation in the Stephan's Quintet compact group of galaxies

Understanding the intergalactic medium (IGM) gas cooling processes, which are necessary to fuel star formation in galaxies, and the effect of galaxy--galaxy and galaxy--IGM interactions, which modify stellar and gas distributions of galaxies in groups and clusters, is vital to construct realistic models of galaxy formation and evolution. The Stephan's Quintet (SQ) compact group of galaxies is a natural laboratory for studying these phenomena because the galaxies of this group are heavily interacting between each other and with the group IGM. Furthermore its vicinity allows to study the details of the interaction phenomena, which are believed to be much more common in the early universe, and its compactness on the sky permits studies of diffuse components associated with the group IGM. In this thesis we present an analysis of a comprehensive set of MIR/FIR observations of Stephan's Quintet, taken with the Spitzer Space Observatory. The emission seen at these wavelengths is produced by dust particles and can be used to trace star formation events, AGN activity and also hot gas cooling, in the case dust emission is powered by collisions between plasma particles and dust. Applying a novel fitting technique to the Spitzer FIR maps, we have been able to separate the different sources of dust emission in this group and perform their photometry at FIR as well as MIR wavelengths. Our study has revealed for the first time the presence of a luminous and extended component of infrared dust emission, not connected with the mainbodies of the group galaxies, and roughly coincident with the X-ray halo of the group. We fitted the inferred dust emission spectral energy distribution of this extended source and the other main infrared emission components of SQ, including the intergalactic shock, to elucidate the mechanisms powering the dust and PAH emission, taking into account dust collisional heating and heating through UV and optical photons. Combining the fraction of dust luminosity powered by UV photons, as derived from the SED fitting, with the UV luminosity directly observed on the GALEX FUV map of SQ, we estimated the star formation rate (SFR) for each dust emitting source, thus providing a complete picture of star formation in SQ embracing obscured and unobscured components. The total SFR of SQ is $7.5~{rm M_odot/yr}$, similar to the value expected for non interacting galaxies of the same mass of SQ galaxies. However the star formation sites are found mainly at the periphery of the galaxies or in the intergalactic medium, at variance with the usual pattern of star formation in field galaxies which is typically distributed in the central regions or main bodies of galaxies. Despite the unusual location of star formation sites, we have found that, for the brightest sources in SQ, the SFR per unit physical area is similar to that characteristic of disk galaxy star formation regions when compared to the corresponding gas column density on a Kennicutt--Schmidt diagram. We also show that even though the detected extended component of dust emission trace the distributed group star formation, available sources of dust in the group halo can provide enough dust to produce up to $L_{IR}approx10^{42}~{rm erg/s}$ powered by collisional heating. This amount, several times higher than the X-ray halo luminosity, could provide an important cooling mechanism for the IGM hot gas. At the end of the thesis we present a theoretical model of a high velocity shock, similar to the one occuring in SQ IGM, taking into account dust cooling and dust destruction. This model shows that, although the efficiency of dust cooling drops quickly because of dust removal by sputtering, the gas cooling time is reduced by a factor of 2-3, compared to the case where only radiative cooling is considered

A novel combination of triple metachronous malignancies of the kidney, oropharynx and prostate. A case report

Synchronous or metachronous malignancies are a rare event, with an incidence rate that increases with age. The present study reports the case of a 70-year-old Caucasian male who was referred to the outpatient office of the Urology Unit, Sapienza University of Rome (Latina, Italy) due to lower urinary tract symptoms. An abdominal ultrasound investigation was performed that demonstrated the presence of a right renal mass. The patient underwent right radical nephrectomy, which resulted in the definitive diagnosis of clear cell type renal cell carcinoma. The patient was eventually diagnosed with triple primary metachronous cancer consisting of renal clear cell carcinoma, prostate adenocarcinoma and squamous cell carcinoma of the oropharynx (palatine tonsil). To the best of our knowledge, this combination of primary neoplasms has not previously been documented

Effects of dance therapy on balance, gait and neuro-psychological performances in patients with Parkinson's disease and postural instability

Postural Instability (PI) is a core feature of Parkinson’s Disease (PD) and a major cause of falls and disabilities. Impairment of executive functions has been called as an aggravating factor on motor performances. Dance therapy has been shown effective for improving gait and has been suggested as an alternative rehabilitative method. To evaluate gait performance, spatial-temporal (S-T) gait parameters and cognitive performances in a cohort of patients with PD and PI modifications in balance after a cycle of dance therapy

Real Costs Assessment of Solar-Hydrogen and Some Fossil Fuels by means of a Combustion Analysis

In order to compare solar-hydrogen and the most used fossil fuels, the evaluation of the "external" costs related to their use is required. These costs involve the environmental damage produced by the combustion reactions, the health problems caused by air pollution, the damage to land from fuel mining, and the environmental degradation linked to the global warming, the acid rains, and the water pollution. For each fuel, the global cost is determined as sum of the market price and of the correspondent external costs. In order to obtain a quantitative comparison, the quality of the different combustion reactions and the efficiency of the technologies employed in the specific application sector have to be considered adequately. At this purpose, an entropic index that considers the degree of irreversibility produced during the combustion process and the degradation of surroundings is introduced. Additionally, an environmental index that measures the pollutants released during the combustions is proposed. The combination of these indexes and the efficiency of the several technologies employed in four energy sectors have allowed the evaluation of the total costs, highlighting an economic scenario from which the real advantages concerning the exploitation of different energy carrier are determined

Theoretical fits of the \delta Cephei light, radius and radial velocity curves

We present a theoretical investigation of the light, radius and radial velocity variations of the prototype $\delta$ Cephei. We find that the best fit model accounts for luminosity and velocity amplitudes with an accuracy better than $0.8\sigma$, and for the radius amplitude with an accuracy of $1.7\sigma$. The chemical composition of this model suggests a decrease in both helium (0.26 vs 0.28) and metal (0.01 vs 0.02) content in the solar neighborhood. Moreover, distance determinations based on the fit of light curves agree at the $0.8\sigma$ level with the trigonometric parallax measured by the Hubble Space Telescope (HST). On the other hand, distance determinations based on angular diameter variations, that are independent of interstellar extinction and of the $p$-factor value, indicate an increase of the order of 5% in the HST parallax.Comment: accepted for publication on ApJ Letter

Prevention of dental caries: a review of effective treatments

The objective of this study is to review medical and non medical treatments for prevention of caries. A comprehensive literature search of the most relevant and updated published studies from 01/01/2002 through December 2015 in PubMed/MEDLINE, Embase and Scopus databases regarding the efficacy of strategies and treatments aiming to prevent the development of caries was performed selecting papers on the basis of the Evidence-based Medicine Criteria. We identified thirty systematic reviews on prevention of caries. Analyzing the data the retrieved literature, performance of prevention treatments seems to be high. Prevention treatments may have a relevant impact on the avoiding the development of caries planning

Far-Infrared Radiative Properties of Water Vapor and Clouds in Antarctica

Abstract Water vapor and clouds are among the most important greenhouse components whose radiative features cover all the broad spectral range of the thermal emission of the atmosphere. Typically more than 40% of the total thermal emission of Earth occurs in the far-infrared (FIR) spectral region from 100 to 667 cm−1 (wavelengths from 100 to 15 µm). Nevertheless, this spectral region has not ever been fully covered down to 100 cm−1 by space missions, and only a few ground-based experiments exist because of the difficulty of performing measurements from high altitude and very dry locations where the atmosphere is sufficiently transparent to observe the FIR emission features. To cover this lack of observations, the Italian experiment "Radiative Properties of Water Vapor and Clouds in Antarctica" has collected a 2-yr dataset of spectral measurements of the radiance emitted by the atmosphere and by clouds, such as cirrus and polar stratospheric clouds, from 100 to 1,400 cm−1 (100–7 µm of wavelength), including the underexplored FIR region, along with polarization-sensitive lidar observations, daily radiosondes, and other ancillary information to characterize the atmosphere above the site. Measurements have been performed almost continuously with a duty cycle of 6 out of 9 h, from the Italian–French base of Concordia at Dome C over the Antarctic Plateau at 3,230 m MSL, in all-sky conditions since 2012. Because of the uniqueness of the observations, this dataset will be extremely valuable for evaluating the accuracy of atmospheric absorption models (both gas and clouds) in the underexplored FIR and to detect possible daily, seasonal, and annual climate signatures

Oncogenic microRNAs characterization in clear cell renal cell carcinoma

A key challenge for the improvement of clear cell renal cell carcinoma (ccRCC) management could derive from a deeper characterization of the biology of these neoplasms that could greatly improve the diagnosis, prognosis and treatment choice. The aim of this study was to identify specific miRNAs that are deregulated in tumor vs. normal kidney tissues and that could impact on the biology of ccRCC. To this end we selected four miRNAs (miR-21-5p, miR-210-3p, miR-185-5p and miR-221-3p) and their expression has been evaluated in a retrospective cohort of formalin-fixed paraffin-embedded (FFPE) tissues from 20 ccRCC patients who underwent surgical nephrectomy resection. miR-21-5p and miR-210-3p resulted the most significantly up-regulated miRNAs in this patient cohort, highlighting these onco-miRNAs as possible relevant players involved in ccRCC tumorigenesis. Thus, this study reports the identification of specific oncogenic miRNAs that are altered in ccRCC tissues and suggests that they might be useful biomarkers in ccRCC management