390 research outputs found

    Real-Time Forecasting of Air Pollution Episodes in the Venetian Region. Part I: The Advection-Diffusion Model. Part II: The Kalman Predictor

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    The object of this overall research, which has an expected duration of two years is to set up a scheme for predicting ground-level pollutant concentrations for real-time control purposes (i.e. the action to be taken at the emission sources in the presence of forthcoming high pollutant events). The forecasting scheme is described, together with its application to sulphur dioxide pollution in the Venetian lagoon area. The scheme is based on a complex mathematical model to be run on a computer and receiving at the beginning of each interval of time all the information (about the meteorological and emission situation) required for the prediction. The type of control action which should be taken on the basis of such a forecast is the object of this part of the research

    Mathematical Models for Planning and Controlling Air Quality; Proceedings of an IIASA Workshop, October 1979

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    Air-quality management problems fall into three main classes: it is difficult to obtain a reliable picture of all the physicochemical processes involved, comprehensive assessments of the costs and benefits of alternative control strategies are not easily made, and the technology for pollution abatement is not yet well established. Various mathematical or formal management models do exist but the overall impact of modeling on decision making has so far been relatively small. The first aim of the IIASA Workshop on which this volume is based was to bridge the gap between air-quality modeling and management. As described in the ten papers in Part One, Workshop participants examined the goals actually pursued by decision makers, the potential role of mathematical models in air-quality management, and the extent to which modeling has been used in real situations in a number of countries. The Workshop's second aim, reported in the eight papers in Part Two, was to consider the unusual strategy of real-time emission control. An extended description of the IIASA case study of the Venetian Lagoon area was presented, together with contributions on real-time forecast and control schemes in operation in Japan and Italy

    Cyclosporin A blocks calcium-dependent pathways of gene activation

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    We have used an interleukin-2 (IL-2) promoter-CAT fusion gene to study activation of IL-2 gene expression by IL-1, phytohemagglutinin (PHA), phorbol myristate acetate (PMA), and calcium ionophore in the murine thymoma line EL4 and the human lymphoma line Jurkat. The two cell lines respond differently to combinations of these stimuli. IL-1 in combination with suboptimal concentration of PMA induced chloramphenicol acetyltransferase (CAT) activity in EL4. In Jurkat cells, IL-1 failed to synergize with PMA or PHA. Cotransfection with the IL-2/CAT gene and a construct capable of expressing murine T-cell type IL-1 receptors converted Jurkat cells to IL-1 responsiveness. IL-1 in combination with PHA but not with PMA resulted in induction of CAT activity in these cells. Induction of IL-2/CAT activity by all stimuli in both cell lines was blocked by the presence of EGTA in the culture medium. EGTA did not inhibit IL-1/PMA activation of an SV40 early promoter-CAT fusion gene in either EL4 or Jurkat cells; therefore, calcium was not required for IL-1 or PMA signal transduction. Jurkat cells were shown to differ from EL4 in their requirement for calcium mobilization. Two different calcium-dependent pathways of gene activation were distinguished, both of which were blocked by the immunosuppressive drug cyclosporin A

    Real-Time Control of Sulphur Dioxide Emissions from an Industrial Area

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    Real-time emission control is an air quality policy which is alternative to permanent emission reduction. In general terms, it consists of controlling emission only when a forthcoming episode is forecast. Thus, control costs are lower than costs due to permanent abatement. The natural application is a case characterized by a limited number of polluting sources. In more specific terms, a real-time emission control scheme consists of the following operations at the beginning of each time interval (hour,say): (i) Collect current concentration and meteorological measures by a monitoring network. (ii) Forecast future values of relevant local meteorological variables. (iii) On the basis of information about current concentration values, forecast meteorology and scheduled emissions predict future concentrations. (iv) If future concentrations exceed some reference level, reduce the scheduled emissions. The paper describes a case study [application of scheme (i)-(iv)] to sulphur dioxide pollution from the industrial area in the Venetian lagoon region. The general characteristics are the following: The meteorological predictors [step (ii)] are simple stochastic mathematical predictors. The concentration predictor [step (iii)] is based on a complex forecast algorithm (Kalman predictor). It is derived from the "stochastic version" of the numerical solution of the advection- diffusion partial differential equation. The control policy [step(iv)] is assumed to consist of mixing with cleaner fuel under the constraint of maintaining the production scheduled by each polluting plant. The results of the case study are supplied as cost-effectiveness curves (cost versus effectiveness of the control action)

    The (decision) tree of fertility: an innovative decision-making algorithm in assisted reproduction technique

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    Purpose: Several mathematical models have been developed to estimate individualized chances of assisted reproduction techniques (ART) success, although with limited clinical application. Our study aimed to develop a decisional algorithm able to predict pregnancy and live birth rates after controlled ovarian stimulation (COS) phase, helping the physician to decide whether to perform oocytes pick-up continuing the ongoing ART path. Methods: A single-center retrospective analysis of real-world data was carried out including all fresh ART cycles performed in 1998–2020. Baseline characteristics, ART parameters and biochemical/clinical pregnancies and live birth rates were collected. A seven-steps systematic approach for model development, combining linear regression analyses and decision trees (DT), was applied for biochemical, clinical pregnancy, and live birth rates. Results: Of fresh ART cycles, 12,275 were included. Linear regression analyses highlighted a relationship between number of ovarian follicles > 17 mm detected at ultrasound before pick-up (OF17), embryos number and fertilization rate, and biochemical and clinical pregnancy rates (p < 0.001), but not live birth rate. DT were created for biochemical pregnancy (statistical power–SP:80.8%), clinical pregnancy (SP:85.4%), and live birth (SP:87.2%). Thresholds for OF17 entered in all DT, while sperm motility entered the biochemical pregnancy’s model, and female age entered the clinical pregnancy and live birth DT. In case of OF17 < 3, the chance of conceiving was < 6% for all DT. Conclusion: A systematic approach allows to identify OF17, female age, and sperm motility as pre-retrieval predictors of ART outcome, possibly reducing the socio-economic burden of ART failure, allowing the clinician to perform or not the oocytes pick-up

    Effectiveness of expressive writing protocol in palliative care healthworkers: A quantitative study

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    Background and aim of the work: Palliative Care professionals are exposed to intense emotional envi-ronment. This puts them at risk for Compassion Fatigue and Burnout. The protective factors that can counter their onset are Compassion Satisfaction, Organizational Commitment and Resilience. Expressive Writing is a valid tool for adapting to traumatic events and enhancing psychological well-being. Aim of this study is to evaluate the effect of the Expressive Writing in Palliative Care professionals on Compassion Satisfaction, Organizational Commitment, Resilience, Compassion Fatigue and perceived distress. Methods: Prospective experimental study with experimental/control groups and pre/post measurements. 50 Palliative Care professionals were recruited in Northern and Central Italy. Participants filled: Organizational Commitment Questionnaire; ProQol-revision III; Resilience Scale for Adults; Impact of Event-Scale Revised; Emotion Thermometer; ad hoc questionnaire for the evaluation of protocol usefulness. Results: Wilcoxon test demon-strated change in Continuative Commitment (Z =-3.357, p = .001), anger (Z =-2.214, p = .027), sleep (Z =-2.268, p = .023), help (Z =-2.184, p = .029), intrusiveness (Z =-2.469, p = .014), hyperarousal (Z =-2.717, p = .007), and total IES (Z =-2.456, p =, 014). Mann Whitney test showed a significantly lower score on post-test Intrusiveness in the experimental group (U = 202, p = .038). Conclusions: The Expressive Writing intervention was effective in improving organizational and emotional variables. Expressive Writing supports healthcare professionals in relieving the burden of traumatic episodes, ordering associated thoughts and emo-tions, and implementing a process of deep comprehension

    Combining Litter Observations with a Regional Ocean Model to Identify Sources and Sinks of Floating Debris in a Semi-enclosed Basin: The Adriatic Sea

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    Visual ship transect surveys provide crucial information about the density, and spatial distribution of floating anthropogenic litter in a basin. However, such observations provide a ‘snapshot’ of local conditions at a given time and cannot be used to deduce the provenance of the litter or to predict its fate, crucial information for management and mitigation policies. Particle tracking techniques have seen extensive use in these roles, however, most previous studies have used simplistic initial conditions based on bulk average inputs of debris to the system. Here, observations of floating anthropogenic macro debris in the Adriatic Sea are used to define initial conditions (number of particles, location, and time) in a Lagrangian particle tracking model. Particles are advected backward and forward in time for 60 days (120 days total) using surface velocities from an operational regional ocean model. Sources and sinks for debris observed in the central and southern Adriatic in May 2013 and March 2015 included the Italian coastline from Pescara to Brindisi, the Croatian island of Mljet, and the coastline from Dubrovnik through Montenegro to Albania. Debris observed in the northern Adriatic originated from the Istrian peninsula to the Italian city of Termoli, as well as the Croatian island of Cres and the Kornati archipelago. Particles spent a total of roughly 47 days afloat. Coastal currents, notably the eastern and western Adriatic currents, resulted in large alongshore displacements. Our results indicate that anthropogenic macro debris originates largely from coastal sources near population centers and is advected by the cyclonic surface circulation until it strands on the southwest (Italian) coast, exits the Adriatic, or recirculates in the southern gyreVersión del edito

    A Journey from Thermally Tunable Synthesis to Spectroscopy of Phenylmethanimine in Gas Phase and Solution

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    Phenylmethanimine is an aromatic imine with a twofold relevance in chemistry: organic synthesis and astrochemistry. To tackle both aspects, a multidisciplinary strategy has been exploited and a new, easily accessible synthetic approach to generate stable imine-intermediates in the gas phase and in solution has been introduced. The combination of this formation pathway, based on the thermal decomposition of hydrobenzamide, with a state-of-the-art computational characterization of phenylmethanimine laid the foundation for its first laboratory observation by means of rotational electric resonance spectroscopy. Both E and Z isomers have been accurately characterized, thus providing a reliable basis to guide future astronomical observations. A further characterization has been carried out by nuclear magnetic resonance spectroscopy, showing the feasibility of this synthetic approach in solution. The temperature dependence as well as possible mechanisms of the thermolysis process have been examined
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