234 research outputs found

    A BMA Analysis to Assess the Urbanization and Climate Change Impact on Urban Watershed Runoff

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    Abstract A reliable planning of urban drainage systems aimed at the mitigation of flooding, should take into account the possible change over time of impervious cover in the urban watershed and of the climate features. The present study proposes a methodology to analyze the changing in runoff response for a urban watershed accounting several plausible future states of new urbanization and climate. To this aim, several models simulating the evolution scenario of impervious watershed area and of climate change were adopted. However, it is known that an evolution scenario represents only one of all possible occurrence and it is not necessary the true future state, therefore it is needed to find the plausible forecast of the future state by taking into account and combining several possible evolution models. According to this aim, in the present study the Bayesian Model Averaging (BMA) approach was applied to several evolution models for climate variables. The Bayesian Model Averaging is a statistic multi-model method that computes a weighted average of the series of available competing models forecast overcoming the problem of arbitrary selecting of single best model and, consequently, the relative requirements of uncertainty analysis. The weighted average is the probability density function (pdf) of the quantity to be forecasted, while the weights correspond to the comparative performance of the models over training period of observation. After the application of BMA, for a given probability, the impervious area extension and the design rainfall event were identified and used as input data for a numerical model based on the SWMM software which was adopted to simulate the behavior of the urban drainage-system adopted as case study. Particularly, the proposed procedure was applied with reference to the Sicilian climate regions (southern Italy)

    Derivation of Clear-Air Turbulence Parameters from High-Resolution Radiosonde Data

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    The knowledge of atmospheric refractive-index structure constant (Cn2) profiles is fundamental to determine the intensity of turbulence, and hence the impact of the scintillation impairment on the signals propagating in the troposphere. However, their relation with atmospheric variables is not straightforward, and profiles based on statistical considerations are normally employed. This can be a shortcoming when performing simulations for which scintillation disturbances need to be consistent with the assumed atmospheric conditions. In order to overcome this limitation, this work describes a procedure to obtain an estimate of the refractive-index structure constant profile under given atmospheric conditions. The procedure is based on the application of the vertical gradient approach to high resolution radiosonde data. The fact that turbulence is confined to vertically thin layers is accounted for by identifying the turbulent layers through the analysis of the Richardson number profiles, and the value of the outer scale length is estimated using the Thorpe length calculated from potential temperature profile. The procedure is applied to high resolution radiosonde data from the SPARC Data Center and the obtained results are consistent with measured Cn2 profiles previously published in the literature

    Adsorption performance and thermodynamic analysis of SAPO-34 silicone composite foams for adsorption heat pump applications

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    Abstract In the present work, adsorption performances of an innovative composite adsorber, based on SAPO-34-silicone composite macro-cellular foams, are reported. The choice of a foamed structure was assessed to improve the water vapor access towards the embedded zeolite keeping good adsorption heat pump dynamic performance. Depending on zeolite amount used as filler, zeolite/silicone foams evidenced a soft and open cell configuration (low zeolite content) or rigid and closed one (high zeolite content). Morphological analysis evidenced that the cellular structure of the foam is homogeneous and well distributed along the foam cross section. Adsorption tests showed that the adsorbent foamed samples have very effective adsorption capabilities indicating that the porous structure of the filled pure zeolite was not obstructed. SAPO-34 filler contributed actively, with an efficiency above 90%, to the adsorption performances of the composite foam. Starting from experimental equilibrium data, a simple thermodynamic analysis based on energy balances was carried out for air conditioning application. Results of the analysis demonstrated that foam technology can guarantee cooling COP up to 7% higher than that estimated for the typical adsorber solution based on loose adsorbent grains inside an aluminum finned-flat tube heat exchanger, which is very promising for practical application in adsorption heat pumps

    Fatal poisoning of four workers in a farm: Distribution of hydrogen sulfide and thiosulfate in 10 different biological matrices

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    We evaluate the distribution of sulfide and thiosulfate (TS) in biological samples of four dairy farmers died inside a pit connected to a manure lagoon. Autopsies were performed 4 days later. Toxicological analyses of sulfide and TS were made using an extractive alkylation technique combined with gas chromatography/mass spectrometry (GC/MS). Autopsies revealed: multiorgan congestion; pulmonary edema; manure inside distal airways of three of the four victims. Sulfide concentrations were cardiac blood: 0.5–3.0 μg/mL, femoral blood: 0.5–1.2 μg/mL, bile: <0.1–2.2 μg/mL; liver 2.8–8.3 μg/g, lung: 5.0–9.4 μg/g, brain: 2.7–13.9 μg/g, spleen: 3.3–6.3 μg/g, fat: <0.1–1.5 μg/g, muscle: 2.6–3.5 μg/g. TS concentrations were cardiac blood: 2.1–4.9 μg/mL, femoral blood: 2.1–2.3 μg/mL, bile: 2.5–4.4 μg/mL, urine: <0.5–1.8 μg/mL; liver <0.5–2.6, lung: 2.8–5.4 μg/g, brain: <0.5–1.9 μg/g, spleen: 1.2–2.9 μg/g, muscle: <0.5–5.6 μg/g. The cause of death was assessed to be acute poisoning by hydrogen sulfide (H2S) for all the victims. Manure inhalation contributed to the death of three subjects. The measurement of sulfide and TS concentrations in biological samples contributed to better understand the sequence of the events. Subjects 3 provided the highest concentration of sulfide in brain, thus, supporting the hypothesis of a rapid loss of consciousness and respiratory depression. One by one, the other farmers entered the pit in attempts to rescue the coworkers but collapsed. Despite the rapid death, subject 3 was the only one with TS detectable in urine. This could be due to differences in metabolism of H2S

    Analysis of cannabinoids and metabolites in dried urine spots (Dus)

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    Dried urine spots (DUS) represent a potential alternative sample storage for forensic toxico-logical analysis. The aim of the current study was to develop and validate a liquid chromatographic tandem mass spectrometric procedure for the detection and quantitative determination of cannabi-noids and metabolites in DUS. A two-step extraction was performed on DUS and urine samples. An LC-MS/MS system was operated in multiple reaction monitoring and positive polarization mode. The method was checked for sensitivity, specificity, linearity, accuracy, precision, recovery, matrix effects and carryover. The method was applied to 70 urine samples collected from healthy volunteers and drug addicts undergoing withdrawal treatment. The method was successfully developed for DUS. LODs lower than 2.0 ng/mL were obtained for all the monitored substances. All the validation parameters fulfilled the acceptance criteria either for DUS or urine. Among the real samples, 45 cases provided positive results for at least one compound. A good quali-quantitative agreement was obtained between DUS and urine. A good stability of THC, THCCOOH and THCCOOH-gluc was observed after a 24 h storage, in contrast to previously published results. DUS seems to provide a good alternative storage condition for urine that should be checked for the presence of cannabinoids and metabolites

    Impact of LAB from Serpa PDO cheese in cheese models: towards the development of an autochthonous starter culture

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    Serpa is a protected designation of origin (PDO) cheese produced with raw ewes’ milk and coagulated with Cynara cardunculus. Legislation does not allow for milk pasteurization and starter culture inoculation. Although natural Serpa’s rich microbiota allows for the development of a unique organoleptic profile, it also suggests high heterogeneity. This raises issues in the final sensory and safety properties, leading to several losses in the sector. A possible solution to overcoming these issues is the development of an autochthonous starter culture. In the present work, some Serpa cheese Lactic acid bacteria (LAB)-isolated microorganisms, previously selected based on their safety, technological and protective performance, were tested in laboratory-scale cheeses. Their acidification, proteolysis (protein and peptide profile, nitrogen fractions, free amino acids (FAA)), and volatiles generation (volatile fatty acids (VFA) and esters) potential was investigated. Significant differences were found in all parameters analyzed, showing a considerable strain effect. Successive statistical analyses were performed to compare cheese models and Serpa PDO cheese. The strains L. plantarum PL1 and PL2 and the PL1 and L. paracasei PC mix were selected as the most promising, resulting in a closer lipolytic and proteolytic profile of Serpa PDO cheese. In future work, these inocula will be produced at a pilot scale and tested at the cheese level to validate their application.info:eu-repo/semantics/publishedVersio

    Work-related stress and well-being in association with epigenetic age acceleration: a Northern Finland Birth Cohort 1966 Study

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    Recent evidence indicates consistent association of low socioeconomic status with epigenetic age acceleration, measured from DNA methylation. As work characteristics and job stressors are crucial components of socioeconomic status, we investigated their association with various measures of epigenetic age acceleration. The study population included employed and unemployed men and women (n=604) from the Northern Finland Birth Cohort 1966. We investigated the association of job strain, effort-reward imbalance and work characteristics with five biomarkers of epigenetic aging (Hannum, Horvath, PhenoAge, GrimAge, and DunedinPoAm). Our results indicate few significant associations between work stress indicators and epigenetic age acceleration, limited to a range of ±2 years, and smoking recording the highest effect on GrimAge age acceleration biomarker between current and no smokers (median difference 4.73 years (IQR 1.18, 8.41). PhenoAgeAA was associated with job strain active work (β=-1.301 95%CI -2.391, -0.212), slowing aging of less than 1.5 years, and working as white-collar slowed aging six months (GrimAgeAA β=-0.683, 95%CI -1.264, -0.102) when compared to blue collars. Association was found for working for more than 40 hours per week that increased the aging over 1.5 years, (HorvathAA β =2.058 95%CI 0.517,3.599, HannumAA β=1.567, 95%CI 0.415,2.719). The pattern of associations was different between women and men and some of the estimated effects are inconsistent with current literature. Our results provide the first evidence of association of work conditions with epigenetic aging biomarkers. However, further epidemiological research is needed to fully understand how work-related stress affects epigenetic age acceleration in men and women in different societies

    Unusual clinical presentation of primary aortoduodenal fistula

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    Primary aorto-enteric fistula (PAEF) develops between the native aorta and the gastro-intestinal tract, in the presence of an abdominal aortic aneurysm. It is a rare, life-threatening condition and appears to be less frequent than secondary aorto- enteric fistula, which is associated with previous aortic prosthetic reconstruction. When untreated, the overall mortality rate is almost 100%. Diagnosis may be challenging until the occurrence of a massive haemorrhage. In the presence of gross contamination, patients tend to a worse prognosis. Extra-anatomical bypass and repair of the enteric tract is the treatment of choice in case of gross contamination. In situ reconstruction is often reported in cases of mild bacterial contamination. Endovascular treatment has recently become a valid option in haemodynamically unstable patients, but a staged approach, with delayed surgical treatment, seems advisable
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