Graph-theoretic approach and sound engineering principles for design of district metered areas

Copyright © 2014 American Society of Civil EngineersThe design of district metered areas (DMAs) in existing water distribution networks, especially in urban areas, involves a high number of decision variables, and the effects of implementing them in districts have to be evaluated in order not to affect the quality of the service to customers. A new methodology for designing a given number of districts in looped water distribution networks is proposed here. It is based on graph theory and takes into account some important DMA design criteria: the maximum and minimum size recommended for a district, the connectedness of each district to the water supply source, and the absence of links between the districts. Therefore, it allows the creation of DMAs that are independent from each other. A recursive bisection procedure has been applied to create districts, while an algorithm for graph traversal has been used to verify whether each district can be reached from the water source and connectivity between the nodes. The successful application of the proposed methodology to a case study has proven its effectiveness for district metered areas design in real urban water distribution networks

Hospital admissions for alcohol-related problems in concomitance with weekends, New Year’s Eve and Christmas Eve: Myth or reality?

This retrospective observational study was carried out by searching the database of the laboratory information system for identifying all requests for alcohol testing placed from emergency departments and intensive care units of the University Hospital of Verona between June 29th, 2012 and December 31st, 2018. The study population consisted of 7488 patients. The number of alcohol tests was more than double in concomitance with New Year’s Eve than in the rest of the year (7.6±6.1 vs 3.1±2.8 requests/day; P<0.001), whereas blood alcohol concentration was similar (1.55 vs 1.12 g/L; P=0.308). The risk of measuring alcohol concentrations >0.1 g/L and >1.0 g/L was 1.9-fold and 1.6-fold higher in concomitance with New Year’s Eve. In multivariate analysis, younger age, female sex and alcohol testing during New Year’s Eve remained significant predictors of alcohol concentrations >0.1 g/L and >1.0 g/L. The requests for alcohol testing were similar in concomitance with Christmas Eve and in other periods of the year, whilst number of requests (4.0±3.2 vs 2.8±2.5 requests/day; P<0.001) and concentration (1.37 vs 0.77 g/L; P<0.001) were higher during weekends than in other weekdays

INFLUENCE OF PULSATILE CATHETER PUMP SYNCHRONIZATION ON HAEMODYNAMIC VARIABLES: NUMERICAL SIMULATION

Severe cardiovascular diseases can be treated using left ventricular assist devices (LVAD). One of the possible LVADs is the Pulsatile Catheter (PUCA) pump that consists of a hydraulically or pneumatically driven membrane pump connected to a valved catheter. In this work a numerical model of the cardiocirculatory system and of the PUCA have been developed in order to study their interaction. In the numerical simulator a pathological condition of the left ventricle has been reproduced and successively the effects of the PUCA on the haemodynamic variables applied were studied. Different functioning modes were tested by changing the ratio between the pump frequency and the heart beat rate (HR) as 1:1, 1:2 or 1:3 and by introducing a delay time between the cardiac and the PUCA cycle. The performance of the pump was evaluated in terms of cardiac output, PUCA and coronary flows and it was studied for different HR values. Results show a good resemblance between the model and literature data and indicate that different synchronization and timing can influence the functioning of the pump. In particular, the frequency ratio and the time delay of the pump cycle can contribute to optimize the performance of the PUCA

Abciximab: a reappraisal of its use in coronary care

Platelet reactivity plays a pivotal role in the pathogenesis of ischemic adverse events during and after acute coronary syndromes (ACS), and percutaneous coronary intervention (PCI). Glycoprotein (GP) IIb/IIIa inhibitors are the strongest antiplatelet agents currently available on the market and three different compounds, namely abciximab, tirofiban, and eptifibatide, have been approved for clinical use. Abciximab has been investigated in the clinical field far more extensively than the other GPIIb/IIIa inhibitors. Abciximab is an anti-integrin Fab fragment of a human – mouse chimeric monoclonal antibody with high affinity and a slow dissociation rate from the GP IIb/IIIa platelet receptor. Abciximab, given shortly before the coronary intervention, is superior to placebo in reducing the acute risk of ischemic complications (EPIC, EPISTENT, EPILOG trials); moreover, in the ISAR-REACT 2 study abciximab has been shown to reduce the risk of adverse events in patients with non ST-segment elevation ACS who are undergoing PCI even after optimal pre-treatment with 600 mg of clopidogrel. Finally, abciximab has been also used in abciximab-coated stent, with only bolus administration regimen and for direct intracoronary use with promising results that may extend and/or modify its current use in clinical practice in future

Prenatal and childhood exposure to per-/polyfluoroalkyl substances (PFASs) and its associations with childhood overweight and/or obesity: a systematic review with meta- analyses

Background. Per-/polyfluoroalkyl substances (PFASs) are persistent organic pollutants and suspected endocrine disrupters. Objective. The aim of this work was to conduct a systematic review with meta-analysis to summarise the associations between prenatal or childhood exposure to PFASs and childhood overweight/obesity. Methods. The search was performed on the bibliographic databases PubMed and Embase with text strings containing terms related to prenatal, childhood, overweight, obesity, and PFASs. Only papers describing a biomonitoring study in pregnant women or in children up to 18 years that assessed body mass index (BMI), waist circumference (WC), or fat mass in children were included. When the estimates of the association between a PFAS and an outcome were reported from at least 3 studies, a meta-analysis was conducted; moreover, to correctly compare the studies, we developed a method to convert the different effect estimates and made them comparable each other. Results. In total, 354 and 565 articles were retrieved from PubMed and Embase, respectively, resulting in a total of 613 articles after merging duplicates. The papers included in this systematic review were 31: 18 evaluating prenatal exposure to PFASs, 11 childhood exposure, and 2 both. Overall, results were conflicting, with positive, negative, and null associations. 17 papers were included in meta-analyses (12 prenatal, 3 children, and 2 both). The method implemented for data conversion allowed a suitable comparison of different effect estimates. Meta-analyses evaluating the associations between prenatal exposure to PFOA, PFOS, PFNA, PFHxS, and the outcomes BMI, WC, and Dual-Energy X-ray Absorptiometry (DXA) showed no significant results. Meta-analyses for the associations between childhood exposure to PFASs and the outcomes BMI showed no significant results except for a negative association between PFNA and BMI (pooled estimate from a random effect model: -0.045; 95%CI: -0.087, -0.002), however, more studies are required to confirm the strength of this association. Conclusion. To increase the reliability of meta-analyses in environmental epidemiology we suggest the conversion of effect estimates to compare different studies. The pooled evidence of the meta-analyses of the present study suggests that there is no overall association between exposure to PFASs and childhood overweight/obesity

INFLUENCE OF PULSATILE CATHETER PUMP SYNCHRONIZATION ON HAEMODYNAMIC VARIABLES: NUMERICAL SIMULATION

Severe cardiovascular diseases can be treated using left ventricular assist devices (LVAD). One of the possible LVADs is the Pulsatile Catheter (PUCA) pump that consists of a hydraulically or pneumatically driven membrane pump connected to a valved catheter. In this work a numerical model of the cardiocirculatory system and of the PUCA have been developed in order to study their interaction. In the numerical simulator a pathological condition of the left ventricle has been reproduced and successively the effects of the PUCA on the haemodynamic variables applied were studied. Different functioning modes were tested by changing the ratio between the pump frequency and the heart beat rate (HR) as 1:1, 1:2 or 1:3 and by introducing a delay time between the cardiac and the PUCA cycle. The performance of the pump was evaluated in terms of cardiac output, PUCA and coronary flows and it was studied for different HR values. Results show a good resemblance between the model and literature data and indicate that different synchronization and timing can influence the functioning of the pump. In particular, the frequency ratio and the time delay of the pump cycle can contribute to optimize the performance of the PUCA

Influence of Pulsatile Catheter Pump Synchronization on Haemodynamic Variables: Numerical Simulation.

Severe cardiovascular diseases can be treated using left ventricular assist devices (LVAD). One of the possible LVADs is the Pulsatile Catheter (PUCA) pump that consists of a hydraulically or pneumatically driven membrane pump connected to a valved catheter. In this work a numerical model of the cardiocirculatory system and of the PUCA have been developed in order to study their interaction. In the numerical simulator a pathological condition of the left ventricle has been reproduced and successively the effects of the PUCA on the haemodynamic variables applied were studied. Different functioning modes were tested by changing the ratio between the pump frequency and the heart beat rate (HR) as 1:1, 1:2 or 1:3 and by introducing a delay time between the cardiac and the PUCA cycle. The performance of the pump was evaluated in terms of cardiac output, PUCA and coronary flows and it was studied for different HR values. Results show a good resemblance between the model and literature data and indicate that different synchronization and timing can influence the functioning of the pump. In particular, the frequency ratio and the time delay of the pump cycle can contribute to optimize the performance of the PUCA

Influenza dei fattori socio-culturali nella percezione di manifesti turistici

Lo scopo del presente lavoro è quello di una indagine sperimentale sull'influenza di variabili socio-culturali nella valutazione delle qualità espressive di manifesti turistici. Si tratta cioè di capire in che modo la rappresentazione delle conoscenze sociali viene impiegata nel giudizio e nella categorizzazione di immagini turistiche, che hanno di per sé un'evidente valenza sociale

Organic aggregates formed by benthopleustophyte brown alga Acinetospora crinita (Acinetosporaceae, Ectocarpales)

This work presents the elemental, polysaccharide, and fatty acid compositions of benthic aggregates formed by the filamentous brown alga cinetospora crinita, which are widely spread on the rocky bottoms of the Mediterranean Sea. The aggregates can be characterized as mineralized centers in which regeneration of nutrients and recycling of dissolved organic matter actively occur and favor the development of an abundant phytoplankton community. Analyses of the stable isotopes of C and N display their marine origin and could provide evidence of the processes that occur inside/outside of the aggregates. The monosaccharide compositions of Adriatic and Tyrrhenian mucilages produced by brown alga A. crinita were quite similar. In particular, the Adriatic sample compositions resembled the average composition of the Tyrrhenian high molecular weight exopolymers, and the observed differences could be ascribed to different degradation stages. The fatty acid patterns found for the aggregates were similar to those observed in the isolated A. crinita algae with variable contributions from embedded diatom species. The bacterial contribution to the fatty acid pool was quite low, most likely due to the known poor conditions for their heterotrophic growth