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Coastal areas are undoubtedly the most vulnerable areas of the marine environment, as they are characterized by a large number of human activities (industries, businesses, tourism, etc.) as well as high population density. Due to the multiple roles that plays and to the many impacts it is subjected to, the coastal marine environment is highly susceptible to pollution. Economical and productive settlements, industries and power plants, tourist and commercial ports involve the presence of numerous discharges that spill into the sea abundant volumes of organic matter, faecal bacteria, viruses and potentially polluting chemical elements (e.g. metals, hydrocarbons, pesticides, etc.). In the light of these considerations, this study refers on the optical properties of cromophoric dissolved organic matter (CDOM) and Escherichia coli concentrations in a bathing area affected by wastewater discharge in the northern Latium, Italy. The application of parallel factor analysis (PARAFAC) to the excitation-emission matrices (EEMs) of CDOM distinguished among three different components: C1 (Ex: 342 nm and Em: 435 nm), C2 (Ex: 281/373 nm and Em: 460 nm) and C3 (Ex: 286 nm and Em: 360 nm), corresponding to the the peak "C" of humic acids of terrestrial origin (C1 and C2) and to the peak "T" characteristic of the tryptophan amino acid (C3). The relative abundance of the peaks C1 and C2 was found to be almost constant at all sampling stations, while the C3 peak was detected in correspondence of stations near the water discharge. Microbiological analysis of coastal water samples showed that the high presence of organic matter from wastewaters was strongly associated with the presence of E. coli cells. Their number decreased with the increase of the distance from the station to the water discharge. By comparing spectral and microbiological results, it has become apparent that tryptophan, whose fluorescence in the water indicates the presence of active bacterial communities ascribable to E. coli, is an excellent tracer of untreated and potentially contaminated waters. The results confirm the usefulness of CDOM fluorescence properties as a proxy of faecal pollution in bathing areas, providing a rapid monitoring tool for promptly management interventions.

In this paper, we present a software architecture, based on RTAI-Linux, for the real-time simulation of dynamic systems and for the rapid prototyping of digital controllers. Our aim is to simplify the testing phase of digital controllers by providing the real-time simulation of the plant with the same interface used for the communication between the control applications and real plant. This unified interface, based on the COMEDI library, allows to switch the controller from the simulated to the real plant without any modification of the control software. Moreover, a set of tools for helping the users in the development of the real-time simulation tasks of the plants have been developed. A great attention has been posed in the automatic generation of symbolic kinematic and dynamic models of robotic manipulators from a description of the robot in terms of kinematic parameters and inertia/center of mass of each link. The system, besides being useful for rapid prototyping of mechatronic control systems, may be used for fault detection, and also as a teaching tool in Mechatronic/Digital Control Courses. A case study, the real-time simulation and control of the PUMA 560 manipulator, is presented and discussed. Copyright © 2007 International Federation of Automatic Control All Rights Reserved.

Great rivers, like Po in the Padana plain, are a main water supply for municipal use; at the same time, however, surface waters are subjected to higher pollution risk, need expensive purification procedures and are exposed to recurrent episodes of drought in the season where higher is the demand for water supply. An interesting alternative resource may be identified in paleo-channels running near the river; such mainly sandy lithosomes are indirectly recharged by the big river and might become as well targets for the implementation of induced recharge project schemes. The paper deals with a sector of the “Po-shallow sandy aquifers complex”, located along the southern bank of the river across the boundaries of Lombardy and Emilia Romagna regions. The area is located 15 km to the west of the city of Ferrara, at the moment depending mainly on the Po river for its public water supply demand. In this area two different sandy aquifer occur, both in indirect recharge relationship with the Po: an upper unconfined Holocenic aquifer and a lower leaky confined Upper Pleistocenic aquifer, separated by a silty-clayey aquitard. Somewhere the two units amalgamate each other so originating a single unconfined high thickness aquifer; in this hydrogeological context it’s peculiar the presence of sand quarry lakes, so directly recharged by the Po. Water quality of this lakes is much better than that one of the Po itself due to the natural attenuation power of the porous medium. The paper shows the results of a groundwater heads and surface water stages continuous monitoring programme (active since July 2002), integrated by hydrochemical data, for studying the processes of pressure and mass transfert of this complex indirect recharge system, to evaluate the water budget of the Settepolesini lake and, trough a numerical modelling, the potential of stimulating induced recharge.

The paper describes a variable stiffness actuated joint based on two counter-acting actuators that operate on two elastic elements purposely designed in order to exhibit a non-linear elastic characteristic.

Vengono esaminati i principali aspetti relativi al dimensionamento di un giunto robotico rotativo con rigidezza variabile, focalizzando l'attenzione sugli aspetti di sintesi e di calcolo di un organo cedevole a rigidezza non lineare.

The aim of this study was to evaluate differences in electrogastrographic activity and serum gastrin secretion in patients subjected to general anesthesia (GA) vs blended anesthesia (BA = GA plus epidural analgesia) for abdominal aortic surgery.Thirty-four patients (all males: 28 with abdominal aorta aneurysm, 6 with obstructive aorto-iliac disease; mean age: 68+/-7 years) were randomly assigned either to GA (N.=17) or to BA (N.=17) for abdominal aortic surgery. Each patient was evaluated for serum gastrin secretion at the time of electrogastrography (EGG) 24 h before and after surgery, using ambulatory equipment. Gastrin levels were tested under fasting conditions and after a standard meal. EGG shows gastric electrical activity that parallels gastric motor activity.Before surgery, no significant difference was found for any of the EGG parameters or the serum gastrin integrated value (area under the curve [AUC]) between the two groups of patients. After surgery, an increased frequency of electrical waves (tachygastria) was observed in 22% of those undergoing GA and in 5% of patients undergoing BA. The power ratio (postprandial/fasting total power) was exceedingly high (4) in 53% of the GA patients and in 11% of the BA patients (P0.05). The gastrin AUC was 263+/-58 pg/mL in the GA group and 179+/-92 pg/mL in the BA group (P0.01).An excess of EGG activity and serum gastrin secretion was observed in patients undergoing GA vs those submitted to BA. Thus, the latter procedure seems to affect gastric function less than GA alone.