Massimo Andretta

Neural Networks for Sulphur Dioxide Ground Level Concentrations Forecasting

In this paper we present the preliminary results on the use of neural networks to forecast SO2 concentration levels in the industrial area of Ravenna. Ground level concentrations of pollutants were analysed in the area of Ravenna, in particular the high levels of SO2 occurring during relatively rare episodes. These events are typically correlated with many different aspects, like complex local meteorology, topography, and industrial emissions parameters. In many cases, during these episodes, the deterministic models (e.g. Gaussian models) fail to explain the high ground level concentrations. The neural networks are trained with a Bayesian learning scheme.

Some Considerations on the Definition of Risk Based on Concepts of Systems Theory and Probability

The concept of risk has been applied in many modern science and technology fields. Despite its successes in many applicative fields, there is still not a well-established vision and universally accepted definition of the principles and fundamental concepts of the risk assessment discipline. As emphasized recently, the risk fields suffer from a lack of clarity on their scientific bases that can define, in a unique theoretical framework, the general concepts in the different areas of application. The aim of this article is to make suggestions for another perspective of risk definition that could be applied and, in a certain sense, generalize some of the previously known definitions (at least in the fields of technical and scientific applications). By drawing on my experience of risk assessment in different applicative situations (particularly in the risk estimation for major industrial accidents, and in the health and ecological risk assessment for contaminated sites), I would like to revise some general and foundational concepts of risk analysis in as consistent a manner as possible from the axiomatic/deductive point of view. My proposal is based on the fundamental concepts of the systems theory and of the probability. In this way, I try to frame, in a single, broad, and general theoretical context some fundamental concepts and principles applicable in many different fields of risk assessment. I hope that this article will contribute to the revitalization and stimulation of useful discussions and new insights into the key issues and theoretical foundations of risk assessment disciplines.

The dawn of dentistry in the late upper Paleolithic: An early case of pathological intervention at Riparo Fredian

OBJECTIVES Early evidence for the treatment of dental pathology is found primarily among food-producing societies associated with high levels of oral pathology. However, some Late Pleistocene hunter-gatherers show extensive oral pathology, suggesting that experimentation with therapeutic dental interventions may have greater antiquity. Here, we report the second earliest probable evidence for dentistry in a Late Upper Paleolithic hunter-gatherer recovered from Riparo Fredian (Tuscany, Italy). MATERIALS AND METHODS The Fredian 5 human consists of an associated maxillary anterior dentition with antemortem exposure of both upper first incisor (I1 ) pulp chambers. The pulp chambers present probable antemortem modifications that warrant in-depth analyses and direct dating. Scanning electron microscopy, microCT and residue analyses were used to investigate the purported modifications of external and internal surfaces of each I1 . RESULTS The direct date places Fredian 5 between 13,000 and 12,740 calendar years ago. Both pulp chambers were circumferentially enlarged prior to the death of this individual. Occlusal dentine flaking on the margin of the cavities and striations on their internal aspects suggest anthropic manipulation. Residue analyses revealed a conglomerate of bitumen, vegetal fibers, and probable hairs adherent to the internal walls of the cavities. DISCUSSION The results are consistent with tool-assisted manipulation to remove necrotic or infected pulp in vivo and the subsequent use of a composite, organic filling. Fredian 5 confirms the practice of dentistry-specifically, a pathology-induced intervention-among Late Pleistocene hunter-gatherers. As such, it appears that fundamental perceptions of biomedical knowledge and practice were in place long before the socioeconomic changes associated with the transition to food production in the Neolithic.

A new model for polluted soil risk assessment

Abstract In this paper, we discuss the most important theoretical aspects of polluted soil Risk Assessment Methodologies, which have been developed in order to evaluate the risk, for the exposed people, connected with the residual contaminant concentration in polluted soil, and we make a short presentation of the major different kinds of risk assessment methodologies. We also underline the relevant role played, in this kind of analysis, by the pollutant transport models. We also describe a new and innovative model, based on the general framework of the so-called Cellular Automata (CA), initially developed in the UE-Esprit Project COLOMBO for the simulation of bioremediation processes. These kinds of models, for their intrinsic “finite and discrete” characteristics, seem to be very well suited for a detailed analysis of the shape of the pollutant sources, the contaminant fates and the evaluation of target in the risk assessment evaluation. In particular, we will describe the future research activities we are going to develop in the area of a strict integration between pollutant fate and transport models and Risk Analysis Methodologies.

Application of the ISCST3 model to an industrial area: comparison between predicted and observed concentrations

This study assesses the performance of the Industrial Source Complex Short Term (ISCST3) model in the industrial area of Ravenna, located in the North East of Italy. The ISCST3 model is based on a steady-state Gaussian plume algorithm. It has been developed by USEPA for assessing air quality impact from point, area, and volume sources. In this work, ISCST3 was applied to simulate the air quality for both a short-term (one hour) and a long-term (annual) period. The model performance has been evaluated by comparing predicted and measured concentrations of NO2, SO2, TPS (Total Suspended Particulate). The software has been tested using the data available from the industrial area of the town and measured by the air quality network of the local Environmental Protection Agency (ARPARER). The model exhibits better performance for long-term than for short-term periods. Generally, simulation of NO2 and TPS is very good with an accuracy between 30 and 50%. The ISCST3 shows lower performances for SO2. It is interesting to note that the SO2 concentration predictions, both shortand long-term, generally appear overvalued. This result could be due to an overestimation of industrial emission fluxes. A more precise estimation of the emission inventory could allow for a better modelling of the pollutant dispersion.

The MRBT model: an analytical dispersion model in a finite mixing layer. Sensitivity analysis and validation against tracer measurements

Abstract This paper describes the characteristics of the MRBT model for studying the dispersion of a pollutant in the lower atmosphere under conditions of spatial homogeneity. The MRBT is shown to be a simple and efficient model based upon a non-stationary analytical solution of the atmospheric dispersion equation in a finite mixing layer. The results of the sensitivity analysis and of validation testing, made with field measurements of tracers carried out at the Nuclear Research Centre in Karlsruhe (Germany), demonstrate the superiority of MRBT with respect to traditional Gaussian models. The model is currently implemented in FORTRAN 77 for the personal computer and is suitable for an initial assessment of short-term atmospheric dispersion with limited computing resources.

Numerical simulation of a rotational symmetric space-charge effect in the near-cathode region

The paper describes the fast and efficient implementation of the charge density method for the computation of the electrostatic potential inside electron guns, taking into account space charge. The results obtained are in good agreement with published experimental measurements. The procedure can be easily extended to systems with diaphragms, saturated emission, and curved cathodes.

Numerical simulation of complex electron optics by the charge density method

A numerical simulation of complex electron optics, typically electrostatically focused CRT, is described. The simulation is based on a charge density method and has very limited memory requirements. It allows an accurate and interactive evaluation of the effects of the geometrical structure and applied voltages on the electron ray shape. The results are compared with a finite-differences large computer simulation and with experimental measurements on spot diameter.

A New Dynamical Model of Biodegradation

A new cellular automata model of the complex set of interacting phenomena which take place in bioremediation is described, which allows to treat a wider set of cases. The model has proven able to accurately describe several experimental data on a pilot plant. The general theory and the C.A. transition function are shown, and an example of the whole framework (fluid dynamics, chemical and biological layer) is analyzed and compared with experimental results.

Poisoning histories in the Italian renaissance: The case of Pico Della Mirandola and Angelo Poliziano

Giovanni Pico della Mirandola and Angelo Poliziano were two of the most important humanists of the Italian Renaissance. They died suddenly in 1494 and their deaths have been for centuries a subject of debate. The exhumation of their remains offered the opportunity to study the cause of their death through a multidisciplinary research project. Anthropological analyses, together with documentary evidences, radiocarbon dating and ancient DNA analysis supported the identification of the remains attributed to Pico. Macroscopic examination did not reveal paleopathological lesions or signs related to syphilis. Heavy metals analysis, carried out on bones and mummified tissues, showed that in Picos remains there were potentially lethal levels of arsenic, supporting the philosophers poisoning theory reported by documentary sources. The arsenic concentrations obtained from analysis of Polizianos remains, are probably more related to an As chronic exposure or diagenetic processes rather than poisoning.