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Provides an overview of the papers included in the 2002 special issue of the 'Philosophical Magazine' which covered the fields of the glass transition, the dynamics of disordered systems and photonic. Presentation of the papers at the Eight International Workshop on Disordered Systems in Andalo, Italy; Number of oral and poster contributions.'

This paper describes a new motion analysis protocol for race-walking. The protocol has been tested under laboratory conditions on a real athlete of the Italian national race-walking team. The experimental setup included a motion capture system and a force platform to record both kinematic and dynamic aspects of the athletic action. Thus, any infringement of the rules can be detected, based on the measure of knee flexion-extension and the loss of ground contact. The biomechanical efficiency can be determined from the joint angles and the temporal components of gait. The results of experiments show that the protocol can be a valuable tool to assist athletes and trainers in improving race-walking technique. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a methodology to describe and compare the economic relative performance of the hospitality sector of the Italian regions during the period 2000–2004. Dynamics of the hospitality sector of each region is represented by the evolution of its economic efficiency. The investigation involves the following steps: a static Data Envelopment Analysis (DEA) to estimate the pure economic efficiency; two different notions of distances between time series and hierarchical clustering techniques are used to classify the economies in the sample. By using a correlation-based distance, three main clusters are detected, while two clusters are identified when the average distance is used. The trend patterns, identified by employing the correlation distance, can be interpreted in terms of exogenous factors that influence the economic efficiency of the group of regions, causing shocks picked up by the high volatility as well as structural breaks. By employing the average distance, one infers information on the cluster that have had similar efficiency values over the period under analysis. This efficiency can be also interpreted in terms of a particular type of hospitality management as well as the firm structure. Following the analysis, some policy and management implications are presented. [Copyright &y& Elsevier]

Abstract: The seismic analysis of a large monument subjected to strong earthquakes is the object of the present paper. As a case study, the response of the “Maniace Castle” of Syracuse has been investigated by a multi-level approach which adopts traditional finite element modelling as well as a specific mechanistic computational model for the final non-linear seismic analyses. At first, the linear behaviour of the monument was studied by means of two 3D FE models in order to understand the global response of the building, its points of weakness, and the kinematics of the corresponding collapse mechanisms. Then, these results were used to calibrate a mechanistic 2D plane rigid body and spring model, RBSM, specifically formulated with the aim of approximating the macroscopic behaviour of masonry walls with reduced degrees of freedom, and taking into account the influence of the masonry texture and energy dissipation capacity of the material. Given the uncertainties and the variability of the material characteristics, an extensive parametric non-linear static analysis and the dynamic analyses, with artificial and natural accelerograms, were made in accord with the EC8 seismic code, and compared together. These results were then used to formulate and verify a simple proposal for the restoration design. [Copyright &y& Elsevier]

Disinfectant demand and microbial inactivation rate are essential issues for assessing disinfection performance and proper design of disinfecting systems. In the United Kingdom and Italy, peracetic acid (PAA) has recently become an accepted disinfectant for treating wastewaters prior to reuse in agriculture, and its use is likely to spread worldwide due to its efficacy as well as the benign nature of the by-products produced. In this paper, overall PAA demand during the advanced disinfection of municipal wastewater for agricultural reuse was evaluated under different experimental conditions. Batch tests were carried out using primary and secondary settled effluents sampled at the City of Taranto municipal wastewater treatment plant. PAA dosages ranged from 1.5 to 8.5 mg/L and from 21 to 40 mg/L for the secondary and primary settled effluents, respectively. Residual PAA was measured after contact times ranging from 1 to 60 min. Results showed that after a strong and almost instantaneous initial disinfectant consumption, the PAA consumption followed first-order kinetics with both effluents. The effluent characteristics affected the values of the parameters in the consumption model. PAA disinfection efficacy was assessed in terms of total coliform and Escherichia coli indicator organism reduction; better results were achieved with the latter. The approximate solution of Hom's model established by Haas and Joffe was used to model inactivation kinetics of both microbial targets. [ABSTRACT FROM AUTHOR]

The article offers information on the "Nonlinear Physics: Theory and Experiment" workshop which was held in Italy from June 22 to July 1, 2006. It is posed that this workshop was part of more than twenty-five years of participation by the University of Leece in Italy in promoting international scientific cooperation in nonlinear science. Representatives from Russia, Poland, France, Australia, and India took part in this workshop.

The article reports on the events of the fourth "Nonlinear Physics: Theory and Experiment IV," conference held at Baia Verde, near Gallipoli, Italy, from June 22 to July 1, 2006. A brief history of the previous congresses on mathematical physics are given. The topics addressed at the conference by the researchers are overviewed.

Purpose: We investigated the clinical performance of (1 → 3)-β- d-glucan (BG), as an early marker of invasive fungal infections (IFI), in different clinical settings. Methods: BG serum levels were assessed by Fungitell (Associates of Cape Cod, Inc), in parallel with galactomannan (GM) when requested by clinicians. By a prospective monocentric study, 270 episodes at risk or with suspect of IFI were enrolled, namely 58 proven-probable invasive aspergillosis (IA), 27 proven invasive candidiasis (IC), 11 possible IC, 16 P.jirovecii pneumonia (PJP), 4 episodes of other IFI and 154 non-IFI controls. Results: We found that (a) the BG overall sensitivity, specificity, positive predictive value and negative predictive value (NPV) were 87.9, 80.5, 76.7 and 89.9 %, respectively; (b) the highest sensitivity was found in the IC groups, followed by PJP, IA and other IFI groups; (c) an association was observed between BG kinetics and patients outcome; (d) in the IA episodes, the combination of BG or GM vs GM alone increased sensitivity from 60.0 to 83.3 % in the haematological patients; (e) false-positive BG results were related to Gram-negative infections or infusion of polyclonal IgM-enriched immunoglobulins, where high levels of BG were indeed detected. Conclusion: Besides strengthening its overall good clinical performance, we provide evidence that serum BG correlates with clinical outcome and that, once used in combination with GM, BG allows to enhance IFI diagnosis rate. The high sensitivity and NPV, observed in the Intensive Care Unit setting, open to BG validation as a marker for assessment of antifungal treatment. [ABSTRACT FROM AUTHOR]

A tall public building in Naples (Italy) has recently undergone a seismic vulnerability assessment, following the new Italian code requirements. The building is about 100 m high and is founded on a piled raft floating in a thick layer of soft pyroclastic and alluvial soils. On the basis of a conventional subsoil classification, the inertial seismic actions on the building would lead to expensive measures for seismic retrofitting. By contrast, if site effects and soil-structure interaction are adequately addressed the picture is completely different. First, free-field seismic response analyses highlighted the beneficial effects of a peat layer, acting as a natural damper on the propagation of shear waves. Finite-element analyses of pile-soil kinematic interaction were then carried out to define the foundation input motion, which was found not to be significantly affected. The effects of inertial interaction were evaluated accounting for soil-foundation compliance; they resulted in an increase of the structural period of vibration, while the overall damping did not change compared to that of the fixed-base structure. The increased structural period led to further reduction of spectral acceleration. The results could lead to significant impacts on the seismic assessment of slender buildings founded on piles embedded in deformable soils. [ABSTRACT FROM AUTHOR]

The use of contemporary technology is widely recognised as a key tool for enhancing competitive performance in swimming. Video analysis is traditionally used by coaches to acquire reliable biomechanical data about swimming performance; however, this approach requires a huge computational effort, thus introducing a delay in providing quantitative information. Inertial and magnetic sensors, including accelerometers, gyroscopes and magnetometers, have been recently introduced to assess the biomechanics of swimming performance. Research in this field has attracted a great deal of interest in the last decade due to the gradual improvement of the performance of sensors and the decreasing cost of miniaturised wearable devices. With the aim of describing the state of the art of current developments in this area, a systematic review of the existing methods was performed using the following databases: PubMed, ISI Web of Knowledge, IEEE Xplore, Google Scholar, Scopus and Science Direct. Twenty-seven articles published in indexed journals and conference proceedings, focusing on the biomechanical analysis of swimming by means of inertial sensors were reviewed. The articles were categorised according to sensor’s specification, anatomical sites where the sensors were attached, experimental design and applications for the analysis of swimming performance. Results indicate that inertial sensors are reliable tools for swimming biomechanical analyses. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the dynamic parameters of poling action during low to moderate uphill skiing in the diagonal stride technique. Twelve elite cross country skiers performed an incremental test using roller skis on a treadmill at 9 km/h at seven different grades, from 2° to 8°. The pole ground reaction force and the pole inclination were measured, and the propulsive force component and poling power were then calculated. The duration of the active poling phase remained unchanged, while the recovery time decreased with the increase in the slope. The ratio between propulsive and total poling forces (effectiveness) was approximately 60% and increased with the slope. Multiple regression estimated that approximately 80% of the variation of the poling power across slopes was explained by the increase of the poling force, the residual variation was explained by the decrease of the pole inclination, while a small contribution was provided by the increase of the poling relative to the cycle time. The higher power output required to ski at a steeper slope was partially supplied by a greater contribution of the power generated through the pole that arises not only by an increase of the force exerted but also by an increase of its effectiveness. [ABSTRACT FROM AUTHOR]

Analyzes the evolution of the size distribution of young firms within some selected industries in Italy. Comparison of empirical evidence with predictions of complementary views of industry dynamics; Application of the kernel density estimator to the data; Speeds of convergence toward the limit distribution.

This study evaluated productivity dynamics and identified sources of productivity growth in Italian tomato production and processing. We used a stochastic frontier input distance function with four error components—heterogeneity, statistical noise, persistent and transient inefficiency—and a four-step estimation procedure with a system generalized method of moments (GMM) estimator in the first step to address the endogeneity problem. The results reveal significant differences in the productivity and efficiency of tomato production and processing. Moreover, there are considerable differences among the different sizes of tomato producers, with the main variations observed for scale efficiency. While tomato processors operate at an optimal production size, tomato producers are characterized by considerable economies of scale, especially small producers. These results thus suggest that there is significant opportunity for technical efficiency improvements at both stages of the value chain. Finally, due to improvements made to scale efficiency, extensive productivity growth was observed for the group of small tomato producers. [ABSTRACT FROM AUTHOR]