Viene qui presentata una metodologia d'approccio basata sull'uso di dati di tipo Shuttle Radar Topography Mission (SRTM) nella risoluzione di problemi legati all'evoluzione geomorfologica di aree di catena ad elevata mobilità tettonica quaternaria. L'ampia area campione prescelta per tale scopo è rappresentata dal bacino intermontano di Auletta, una depressione tettonica bordata da scarpate di linea di faglia a sviluppo decakilometrico e andamento N120-130°, colmata da sedimenti marino-transizionali e continentali di età compresa tra il Pliocene medio ed il Pleistocene medio. Le informazioni estratte dai dati topografici SRTM (elevazione, slope e aspect) sono state utilizzate, unitamente ai dati dell'analisi morfostrutturale tradizionale, per la comprensione dell'evoluzione del rilievo e per definire in tal senso il ruolo delle grandi strutture perimetrali. L'elaborazione dei dati ha inoltre facilitato il calcolo del tasso di erosione sul medio-lungo termine, grazie alla diffusa presenza di marker del sollevamento quaternario come le superfici erosionali sospese.

Recent results from the WAGRIT project (Web for AGRIculture and environmenT), funded by the Italian Space Agency, have seen the development of algorithms for the classification and segmentation of remotely sensed images. The goal is to provide a client-server Internet application for agricultural monitoring of cultivated areas, exploiting remotely sensed high spectral resolution images.

In this paper we will focus on knowledge dissemination and training on Numerical Grid Generation (NGG) and Computational Field Simulation (CFS) carried out by classroom and online combined strategies. We update presentation of activities and events of the European Atelier for Engineering and Computational Sciences, EUA4X, a three year project (2005-2007) financed by the European Union Marie Curie Conferences and Training Courses (Contract\# MSCF-CT-2004-013336). We illustrate the integrated training approach and its scientific contents, we describe the organizational steps of courses and conference type events and we present advances of the web environments designed at IAC to allow permanent online Atelier activities.

Design/methodology/approach - The method relies on alternation of identification of the active genes using a mixture model and clustering of the samples based on Ward hierarchical clustering. The initial-point of the procedure is obtained by means of a ?2 test. The method attempts to locally minimize the sum of the within cluster sample variances under a suitable Gaussian assumption on the distribution of data. Findings - This paper illustrates the proposed methodology and its success by means of results from both simulated and real cDNA microarray data. The comparison of the results with those from a related known method demonstrates the superiority of the proposed approach. Research limitations/implications - Only empirical evidence of algorithm convergence is provided. Theoretical proof of algorithm convergence is an open issue. Practical implications - The proposed methodology can be applied to perform cDNA microarray data analysis. Originality/value - This paper provides a contribution to the development of successful statistical methods for cDNA microarray data analysis.

The paper addresses the calculation of the value at risk (VaR) of the mathematical provision applied in a fair valuation context. Following a balance-sheet approach, the classical definition of VaR needs some clarifications. For identifying worst cases it is opportune to observe that an increase in the value of the liability corresponds to expenses or, better, additional costs, which may result in either a profit shrinkage or a proper loss. Therefore, the classical portfolio return distribution can be redesigned as a liability cost distribution, where critical values lie in the right-hand tail. In the case of the mathematical provision, the expected cost can be easily linked to the expected value of the reserve at the end of the risk horizon. After an overall view on the VaR problems from a managerial perspective, the paper presents, the choice of the VaR model and the number of risk factors to take into account, in addition to describing the calculation technique. The calculation, performed using a simulation approach, is developed as an application case of a life annuity portfolio and provides an estimate of the worst-case loss at a fixed confidence level after a fixed period of time.

The study of complex hereditary diseases is a very challenging area of research. The expanding set of in silico approaches offers a flourishing ground for the acceleration of meaningful findings in this area by exploitation of rich and diverse sources of omic data. These approaches are cheap, flexible, extensible, often complementary and can continuously integrate new information and tests to improve the selection of genes responsible for hereditary diseases. Following this principle, we improved and extended our web-service TOM for the identification of candidate genes in the study of complex hereditary diseases.

Glioblastoma multiforme (GBM) is,the most common and lethal primary brain tumor in adults. We combined neuroimaging and DNA microarray analysis to create a multidimensional map of gene-expression patterns in GBM that provided clinically relevant insights into tumor biology. Tumor contrast enhancement and mass effect predicted activation of specific hypoxia and proliferation gene-expression programs, respectively. Overexpression of EGFR, a receptor tyrosine kinase and potential therapeutic target, was also directly inferred by neuroimaging and was validated in an independent set of tumors by immunohistochemistry. Furthermore, imaging provided insights into the intratumoral distribution of gene-expression patterns within GBM. Most notably, an "infiltrative" imaging phenotype was identified that predicted patient outcome. Patients with this imaging phenotype had a greater tendency toward having multiple tumor foci and demonstrated significantly shorter survival than their counterparts. Our findings provide an in vivo portrait of genome-wide gene expression in GBM and offer a potential strategy for noninvasively selecting patients who may be candidates for individualized therapies.

Biotechnology is an area of great innovations that promises to have deep impact on everyday life thanks to profound changes in biology, medicine, and health care. This article will span from the description of the biochemical principles of molecular biology to the definition of the physics that supports the technology and to the devices and algorithms necessary to observe molecular events in a controlled, portable, and highly parallel manner. Throughout this discussion, constant attention will be given to the ultimate goals and applications of these innovations as well as to the related issues.

Il bioventing e' una tecnologia di decontaminazione del sottosuolo. Alcune specie batteriche presenti nel sottosuolo stesso biodegradano l'inquinante - ad esempio un idrocarburo - mediante un processo che richiede ossigeno; quest'ultimo e' fornito per mezzo di iniezione di aria in pozzi praticati nella zona inquinata del sottosuolo. Verra' presentato un modello matematico - basato sulla teoria del moto dei fluidi multifase in mezzi porosi e sulle equazioni della dinamica delle popolazioni - descrivente il fenomeno fisico ed utile per la simulazione numerica. Il problema della progettazione ottimale dell'intervento di bonifica consiste nel determinare numero, posizione e portata dei pozzi di iniezione di aria, al fine di massimizzare la velocita' di biodegradazione.

An account of the error and the convergence theory is given for Gauss-Laguerre and Gauss-Radau-Laguerre quadrature formulae. We develop also truncated models of the original Gauss rules to compute integrals extended over the positive real axis. Numerical examples confirming the theoretical results are given comparing these rules among themselves and with different quadrature formulae proposed by other authors (Evans, Int. J. Comput. Math. 82:721-730, 2005; Gautschi, BIT 31:438-446, 1991).

For host survival, the immune system (IS) is required to deliver high-level, specific and continuous performance, dealing with a very complex universe of stimuli and functions, as well as physical and resource constraints. From this perspective, the immune system needs an effective strategy to assure the requested operational functions, to survive and to evolve. The concept of degeneracy discussed in this chapter, is the ability of some immune receptors to bind many types of ligands and it would appear to be a fundamental characteristic for immune system functioning as well as a formidable weapon in the architecture of complex biological structures and systems. In this chapter, we will discuss how degeneracy acts as a strategy to optimize the necessary trade-off between the inescapable promiscuity of receptors and ligands, with the necessity to produce a specific response, and how the degeneracy principle acts to set up a memory of each immunological event, thus contributing to the fitness of the organism, and how degeneracy can be considered among the underlying causes for the evolution and robustness of the IS.

The search for longevity genes has greatly developed in recent years basing on the idea that a consistent part of longevity is determined by genetics. The ultimate goal of this research is to identify possible genetic determinants of human aging and longevity, but studies on humans are limited by a series of critical restrictions. For this reason, most of the studies in this field have been, and still are, performed on animal models, basing on the assumption that fundamental biological mechanisms are highly conserved throughout evolution and that, accordingly, extrapolation from model systems to humans is quite reasonable. Indeed, many comparative data obtained on single genes or gene families fit with this assumption. However, it is also clear that, despite such a basic conservative scenario, major changes also occurred in evolution, particularly regarding biological regulatory processes and integration between and among pathways. This consideration raises the fundamental question of the transferability of the results obtained from model systems to humans. In this review, we discuss the differences between animal models and men regarding the genetics of aging and longevity, and the possible reasons that can explain such discrepancies, with a particular emphasis on the phenomena of conservation and evolvability of biological systems. Finally we will suggest a possible strategy to identify putative longevity genes basing on their position inside conserved metabolic structures.

We study the numerical approximation of solutions for parabolic integro-differential equations (PIDE). Similar models arise in option pricing, to generalize the Black-Scholes equation, when the processes which generate the underlying stock returns may contain both a continuous part and jumps. Due to the non-local nature of the integral term, unconditionally stable implicit difference schemes are not practically feasible. Here we propose using implicit-explicit (IMEX) Runge-Kutta methods for the time integration to solve the integral term explicitly, giving higher-order accuracy schemes under weak stability time-step restrictions. Numerical tests are presented to show the computational efficiency of the approximation.

The multiyear problem of a two-body system consisting of a Reissner–Nordström black hole and a charged massive particle at rest is here solved by an exact perturbative solution of the full Einstein–Maxwell system of equations. The expressions of the metric and of the electromagnetic field, including the effects of the electromagnetically induced gravitational perturbation and of the gravitationally induced electromagnetic perturbation, are presented in closed analytic formulas.

Can a directed graph be completed to a directed line graph? If possible, how many arcs must be added? In this paper we address the above questions characterizing partial directed line (PDL) graphs, i.e., partial subgraph of directed line graphs. We show that for such class of graphs a forbidden configuration criterion and a Krausz's like theorem are equivalent characterizations. Furthermore, the latter leads to a recognition algorithm that requires worst case time, where m is the number of arcs in the graph. Given a partial line digraph, our characterization allows us to find a minimum completion to a directed line graph within the same time bound. The class of PDL graphs properly contains the class of directed line graphs, characterized in [J. Blazewicz, A. Hertz, D. Kobler, D. de Werra, On some properties of DNA graphs, Discrete Appl. Math. 98(1-2) (1999) 1-19], hence our results generalize those already known for directed line graphs. In the undirected case, we show that finding a minimum line graph edge completion is NP-hard, while the problem of deciding whether or not an undirected graph is a partial graph of a simple line graph is trivial.