2,734 research outputs found

    Development of a laboratory test procedure for the evaluation of potential gaseous emissions of asphalt rubber bituminous mixtures

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    The superior performance of bituminous mixtures containing crumb rubber from end-of-life tyres has been widely documented from a structural and functional point of view. However, potential impact of the use of crumb rubber on the health of workers in pavement construction sites has been the subject of a limited number of investigations, with a consequent gap in currently available technical knowledge. Following previous research work focused on the chemical analysis of fumes sampled on site, in this paper the Authors present results obtained in the development of a laboratory test procedure for the evaluation of gaseous emissions of asphalt rubber bituminous mixtures in standard, controlled conditions unaffected by site-specific factors. The investigation included monitoring of emissions at the paver's driving seat and at the screed during the laying of gap-and dense-graded wearing course mixtures in three different sites. Laboratory tests were performed by following a fume-generation protocol and by measuring the contents of volatile organic compounds and polycyclic aromatic hydrocarbons in produced emissions. Comparison of results derived from laboratory and field data was carried out in absolute terms and within a carcinogenic risk assessment model. It was found that the proposed laboratory procedure yields emissions which in most cases are similar to those recorded on site at the paver's screed and that lead to a conservative risk estimat

    Environmental Health Literacy: an index to study its relations with pro-environmental behaviors

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    The citizen’ awareness about environmental health risks has been identified as an important determinant of citizens’ choices for the adoption of pro-environmental behaviors, but for its study simple measures to be applied in population studies are still lacking. The Environmental Health Literacy (EHL), is a recent sub-cathegory of health literacy, including functional, critical and interactive dimensions, that can be applied in surveys on environmental health risk perception and behaviors. The aim of our study was to elaborate and validate an EHL Index (ELHI) using data from a large multicenter survey carried out among 4778 students of different disciplines in 15 Italian Universities, with a self-administered anonymous questionnaire investigating risk perceptions, attitudes and behaviors towards environmental health risks and including a simple Functional Health Literacy test (FHL). From the original questionnaire of 56 items three sets of questions were selected to represent the three dimensions of health literacy (Functional, Critical or Interactive) and their outcomes were compared with the answers about FHL test and pro-environmental behaviors. The Principal Component Analysis was used to select the most representative questions that were then grouped in the EHLI. The index was significantly associated with both FHL test and behaviors questions. The ROC curve indicated a satisfying accuracy and was used to identify the best cut-off for ELHI. In conclusion the constructed ELHI can be considered reliable and useful for further population surveys in similar target people to plan communication interventions about environmental health risks and their prevention through individual choices

    X-ray spectroscopy of the z=6.4 quasar J1148+5251

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    We present the 78-ks Chandra observations of the z=6.4z=6.4 quasar SDSS J1148+5251. The source is clearly detected in the energy range 0.3-7 keV with 42 counts (with a significance ≳9σ\gtrsim9\sigma). The X-ray spectrum is best-fitted by a power-law with photon index Γ=1.9\Gamma=1.9 absorbed by a gas column density of NH=2.0−1.5+2.0×1023 cm−2\rm N_{\rm H}=2.0^{+2.0}_{-1.5}\times10^{23}\,\rm cm^{-2}. We measure an intrinsic luminosity at 2-10 keV and 10-40 keV equal to ∼1.5×1045 erg s−1\sim 1.5\times 10^{45}~\rm erg~s^{-1}, comparable with luminous local and intermediate-redshift quasar properties. Moreover, the X-ray to optical power-law slope value (αOX=−1.76±0.14\alpha_{\rm OX}=-1.76\pm 0.14) of J1148 is consistent with the one found in quasars with similar rest-frame 2500 \AA ~luminosity (L2500∼1032 erg s−1L_{\rm 2500}\sim 10^{32}~\rm erg~s^{-1}\AA−1^{-1}). Then we use Chandra data to test a physically motivated model that computes the intrinsic X-ray flux emitted by a quasar starting from the properties of the powering black hole and assuming that X-ray emission is attenuated by intervening, metal-rich (Z≥Z⊙Z\geq \rm Z_{\odot}) molecular clouds distributed on ∼\simkpc scales in the host galaxy. Our analysis favors a black hole mass MBH∼3×109M⊙M_{\rm BH} \sim 3\times 10^9 \rm M_\odot and a molecular hydrogen mass MH2∼2×1010M⊙M_{\rm H_2}\sim 2\times 10^{10} \rm M_\odot, in good agreement with estimates obtained from previous studies. We finally discuss strengths and limits of our analysis.Comment: 9 pages, 3 figures, 1 table, MNRAS in pres

    Determination of total vanadium and vanadium(V) in groundwater from Mt. Etna and estimate of daily intake of vanadium(V) through drinking water.

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    Vanadium(V) can be found in natural waters in the form of V(IV) and V(V) species, which have different biological properties and toxicity. The purpose of this study was to determine the concentrations of total V and V(V) in groundwater from the area of Mt. Etna and to assess the estimated daily intake (EDI) of V(V) of adults and children through drinking water. Water was sampled monthly at 21 sites in 2011. Total vanadium was determined by inductively coupled plasma-mass spectrometry (ICP-MS) and speciation by ion chromatography-ICP-MS (IC-ICP-MS). The concentration of V(V) species ranged from 62.8 to 98.9% of total V, with significantly higher concentrations in samples from the S/SW slope of Mt. Etna. The annual mean concentrations of total V exceeded the Italian legal limit of 140 μg/L at four sites on the S/SW slope. In the absence of thresholds for V(V) intake, only the Environmental Protection Agency (EPA) has calculated a reference dose. Children's EDI of V(V) at the sites with the higher V concentrations exceeded EPA thresholds (9 μg/kg/day). In particular, we found in Camporotondo, Mascalucia, Ragalna and San Pietro Clarenza sites children's EDIs of 11, 9.3, 11 and 9.9, respectively. The EDI of V(V) was significantly higher than the literature range (0.09–0.34 μg/kg/day)

    An Atlas of Altered Expression of Deubiquitinating Enzymes in Human Cancer

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    BACKGROUND: Deubiquitinating enzymes (DUBs) are proteases that process ubiquitin (Ub) or ubiquitin-like gene products, remodel polyubiquitin(-like) chains on target proteins, and counteract protein ubiquitination exerted by E3 ubiquitin-ligases. A wealth of studies has established the relevance of DUBs to the control of physiological processes whose subversion is known to cause cellular transformation, including cell cycle progression, DNA repair, endocytosis and signal transduction. Altered expression of DUBs might, therefore, subvert both the proteolytic and signaling functions of the Ub system. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we report the first comprehensive screening of DUB dysregulation in human cancers by in situ hybridization on tissue microarrays (ISH-TMA). ISH-TMA has proven to be a reliable methodology to conduct this kind of study, particularly because it allows the precise identification of the cellular origin of the signals. Thus, signals associated with the tumor component can be distinguished from those associated with the tumor microenvironment. Specimens derived from various normal and malignant tumor tissues were analyzed, and the "normal" samples were derived, whenever possible, from the same patients from whom tumors were obtained. Of the ∼90 DUBs encoded by the human genome, 33 were found to be expressed in at least one of the analyzed tissues, of which 22 were altered in cancers. Selected DUBs were subjected to further validation, by analyzing their expression in large cohorts of tumor samples. This analysis unveiled significant correlations between DUB expression and relevant clinical and pathological parameters, which were in some cases indicative of aggressive disease. CONCLUSIONS/SIGNIFICANCE: The results presented here demonstrate that DUB dysregulation is a frequent event in cancer, and have implications for therapeutic approaches based on DUB inhibition

    Metabolic Changes Associated with Different Levels of Energy Deficits in Mediterranean Buffaloes during the Early Lactation Stage: Type and Role of the Main Lipid Fractions Involved

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    Cell function and energy redistribution are influenced by lipid classes (phospholipids (PLs), free fatty acids (FFAs), triglycerides (TGs), and cholesterol esters (CEs)). The aim of this study was to investigate metabolic alterations that are related to changes in lipid classes according to different levels of energy deficits in early lactating Mediterranean buffaloes (MBs). Sixty-three MBs were enrolled at the beginning of lactation using an observational study with a cross-sectional experimental design. Serum β-hydroxybutyrate (BHB) levels were used to group the animals into a healthy group (Group H; n = 38; BHB < 0.70 mmol/L) and hyperketonemia risk group (Group K; n = 25; BHB ≥ 0.70 mmol/L). Statistical analysis was performed using a linear model that included the effect of the group and body condition score to assess differences in fatty acid (FA) concentrations. A total of 40 plasma FAs were assessed in each lipid class. Among the FAs, eight PLs, seven FFAs, four TGs, and four CEs increased according to BHB levels, while three FFAs, three TGs, and one CE decreased. The changes among lipid class profiles suggested the influence of inflammatory response, liver metabolism, and the state of body lipid reserves. In addition, the possible similarities of buffaloes at risk of hyperketonemia with ketotic cows suggest the necessity of further investigations in these ruminants

    Dietary habits and thyroid cancer risk: A hospital-based case-control study in Sicily (South Italy).

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    Abstract Several studies have investigated the role of diet as a risk and/or protective factor against thyroid cancer, both considering individual foods, groups of foods and dietary patterns, but the results are not consistent. The aim of the study was to investigate the relationship between dietary habits and thyroid cancer. Cases and controls were recruited at the University Hospital "G. Rodolico" of Catania. The dietary habits were defined through the "Lifestyle Assessment Questionnaire". The frequency of consumption of each food item was reported on a 4-level scale (never, one time a week, 2–3 times a week, every day of the week). We computed the odds ratios (ORs) of thyroid cancer and the corresponding 95% confidence intervals (CIs) according to the median of control group daily intake of each food group, using multiple logistic regression models adjusted for major confounding factors. Starchy foods (OR = 1.39, 95% CI 0.83–2.32), sweets (OR = 1.39, 95% CI 0.81–2.40) and products rich in salt and fat showed a positive association with thyroid cancer risk. Conversely, an inverse association with disease risk was found for vegetables (cruciferous OR = 0.30, 95% CI 0.10–0.92, non cruciferous OR = 0.57 (0.20–1.57) milk and dairy products (OR = 0.68, 95% CI 0.40–1.13) and seafood (OR = 0.68, 95% CI 0.34–1.22). An increased risk was observed for consumption of iodized salts (OR 2.06, 95% CI 1.21–3.51), tea (OR = 1.42, 95% CI 0.84–2.41) and coca-cola (OR = 3.08, 95% CI 1.53–6.20). Finally, our results confirm the protective effect of a daily water intake of 1–2 L, but unfortunately this quantity is usually consumed by about a quarter of the sample. Dietary habits appear to modify the risk of thyroid carcinoma. A diet with a limited consumption of starchy foods, products rich in salt, fat and sugar and a higher consumption of, cruciferous/non-cruciferous vegetables, milk and dairy products and seafood could be protective towards thyroid cancer. Moreover, the water intake should be increased and the actual need to consume iodized salt should be verified for each subject/area. These results warrant further investigations and, if confirmed, they might have important public health implications for the reduction of thyroid cancer through the improvement of dietary habits

    The fraction and kinematics of broad absorption line quasars across cosmic time

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    Luminous quasars are powerful targets to investigate the role of feedback from supermassive black-holes (BHs) in regulating the growth phases of BHs themselves and of their host galaxies, up to the highest redshifts. Here we investigate the cosmic evolution of the occurrence and kinematics of BH-driven outflows, as traced by broad absorption line (BAL) features, due to the C IV ionic transition. We exploit a sample of 1935 quasars quasars at z=2.1−6.6z=2.1-6.6 with bolometric luminosity log(Lbol/L_{\rm bol}/erg s−1)≳46.5^{-1})\gtrsim46.5, drawn from the Sloan Digital Sky Survey and from the X-shooter legacy survey of Quasars at Reionisation (XQR-30). We consider rest-frame optical bright quasars to minimise observational biases due to quasar selection criteria. We apply a homogeneous BAL identification analysis, based on employing composite template spectra to estimate the quasar intrinsic emission. We find a BAL quasar fraction close to 20\% at z∼2−4z\sim2-4, while it increases to almost 50\% at z∼6z\sim6. The velocity and width of the BAL features also increase at z≳4.5z\gtrsim4.5. We exclude that the redshift evolution of the BAL properties is due to differences in terms of quasar luminosity and accretion rate. These results suggest significant BH feedback occurring in the 1 Gyr old Universe, likely affecting the growth of BHs and, possibly, of their host galaxies, as supported by models of early BH and galaxy evolution.Comment: Accepted for publication in Ap
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