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This paper deals with the motion planning problem for a dual-arm manipulation system, whose task is to transport a long object. The described manipulation planning problem is characterised by the necessity of performing grasp, ungrasp and regrasp operations on the movable object, in order to avoid the obstacles cluttering the workspace. These operations lead to changes in the kinematic structure of the robotic chain, imposing different constraints on the motion of the arms. A general solution to manipulation planning leads to consider configuration spaces characterised by a high dimension: thus, it is useful to develop heuristic strategies for solving the problem in a reasonable amount of time. Here, we propose a simple strategy, basing the construction of the manipulation path on the motion of the object. This strategy requires to solve several instances of the motion planning problem, that are faced by means of a hierarchical multilevel discretization in conjunction with a multisource weighted distance field. This allows us to reduce the computational complexity and to get a feasible procedure. The performances of the procedure are evaluated on a typical example involving a two arms system.

We recently showed in a pig model of ex vivo lung perfusion (EVLP) that lung edema correlates with glucose consumption. We investigated whether salbutamol, a β-adrenergic receptor agonist known to upregulate fluid transport in the lung, modulates glucose concentration in the perfusate during EVLP.Lungs from domestic pigs underwent normothermic EVLP. At the end of controlled reperfusion, lungs were ventilated and perfused for 60 minutes, then randomized to salbutamol (β-Agonist) infusion or placebo (Control) for 180 minutes. Functional parameters were assessed.In the β-Agonist group, glucose concentration decreased over time more than corresponding Control values (analysis of variance [ANOVA], p = 0.05). Mean pulmonary artery pressure (mPAP) was 16 ± 1 mm Hg in the β-Agonist group vs 21 ± 1 mm Hg in the Controls (ANOVA p0.05). Baseline mPAP was correlated with the drop of mPAP after the β-agonist infusion (R(2) = 0.856, p0.05). Dynamic compliance dropped from 51 ± 10 to 31 ± 6 ml/cm H(2)O in the β-Agonist group and from 60 ± 4 to 21 ± 3 ml/cm H(2)O in the Control group (ANOVA, p0.05 β-agonist vs Control). The Δ partial pressure of oxygen/fraction of inspired oxygen was 418 ± 15 and 393 ± 12 mm Hg in the β-Agonist and Control groups, respectively (t-test p = 0.106).Glucose concentration in the perfusate was affected by salbutamol. Salbutamol was associated with lower pulmonary pressures and better lung mechanics. These data suggest a possible role for salbutamol as a pharmacologic adjunct during EVLP before transplantation.

RATIONALE: Unphysiologic strain (the ratio between tidal volume and functional residual capacity) and stress (the transpulmonary pressure) can cause ventilator-induced lung damage. OBJECTIVES: To identify a strain-stress threshold (if any) above which ventilator-induced lung damage can occur. METHODS: Twenty-nine healthy pigs were mechanically ventilated for 54 hours with a tidal volume producing a strain between 0.45 and 3.30. Ventilator-induced lung damage was defined as net increase in lung weight. MEASUREMENTS AND MAIN RESULTS: Initial lung weight and functional residual capacity were measured with computed tomography. Final lung weight was measured using a balance. After setting tidal volume, data collection included respiratory system mechanics, gas exchange and hemodynamics (every 6 h); cytokine levels in serum (every 12 h) and bronchoalveolar lavage fluid (end of the experiment); and blood laboratory examination (start and end of the experiment). Two clusters of animals could be clearly identified: animals that increased their lung weight (n = 14) and those that did not (n = 15). Tidal volume was 38 ± 9 ml/kg in the former and 22 ± 8 ml/kg in the latter group, corresponding to a strain of 2.16 ± 0.58 and 1.29 ± 0.57 and a stress of 13 ± 5 and 8 ± 3 cm H(2)O, respectively. Lung weight gain was associated with deterioration in respiratory system mechanics, gas exchange, and hemodynamics, pulmonary and systemic inflammation and multiple organ dysfunction. CONCLUSIONS: In healthy pigs, ventilator-induced lung damage develops only when a strain greater than 1.5-2 is reached or overcome. Because of differences in intrinsic lung properties, caution is warranted in translating these findings to humans

METHODS: Change in eGFR was estimated as % change from the first to last eGFR (CKD-EPI creatinine) in a 2-year baseline period. We modeled the hazard ratios (HRs) of subsequent mortality as a spline function of % change in eGFR after adjusting for age, sex, race, first eGFR, and co-morbid conditions. We used random effects meta-analyses to combine results stratified by first baseline eGFR (

The paper describes a GSPN-based approach to performance evaluation of message-passing parallel architectures, taking into account both the effects of the synchronization schemes and the interconnection topology. Two classes of problems are specifically addressed: the behavior of regular computational structures in which data exchange and interprocess synchronization require communication only among processors that are physically connected communication only among processors that are physically connected is investigated first. Then, the effect of differences in topology and interconnection schemes of the processing elements is assessed under a series/parallel computational workload. The effectiveness of the modeling technique for this class of architectures is demonstrated by its ability in representing different interaction policies and in describing the relationships between computational workload and physical resources, along with the efficiency in obtaining significant performance results.

Resistant hypertension is defined as blood pressure that remains above the target of140/90 mm Hg in the general population and130/80 mm Hg in people with diabetes mellitus or chronic kidney disease (CKD) in spite of the use of at least three full-dose antihypertensive drugs including a diuretic, or as blood pressure that reaches the target by means of four or more drugs. Hypertension is a frequent complication in CKD and a determining factor in the progression of renal damage, especially in proteinuric and diabetic patients, as well as contributing to a high cardiovascular risk. Clinical practice guidelines recommend blood pressure levels below 130/80 mm Hg in all CKD patients, but the target is reached in only a small proportion (10-20%), both in nephrology and non-nephrology settings. The resistance to antihypertensive treatment may be considered one of the causes of the poor achievement of blood pressure targets in CKD patients.

With the increasing number of genomes being sequenced, a major objective is to transfer accurate annotation from characterised proteins to uncharacterised sequences. Consequently, comparative genomics has become a usual and efficient strategy in functional genomics. The release of various annotated genomes of plants, such as O. sativa and A. thaliana, has allowed setting up comprehensive lists of gene families defined by automated methods. However, like for gene sequence, manual curation of gene families is an important requirement that has to be undertaken. GreenPhylDB comprises protein sequences of 12 plant species fully sequenced that were grouped into homeomorphic families using similarity-based methods. Clusters are finally processed by phylogenetic analysis to infer orthologs and paralogs that will be particularly helpful to study genome evolution. Previously, each cluster has to be curated (i.e. properly named and classified) using different sources of information. A web interface for plant gene families’ curation was developed for that purpose. This interface, accessible on GreenPhylDB ("http://greenphyl.cirad.fr":http://greenphyl.cirad.fr), centralizes external references (e.g. InterPro, KEGG, Swiss-Prot, PIRSF, Pubmed) related to all gene members of the clusters and shows statistics and automatic analysis. We believe that this synthetic view of data available for a gene cluster, combined with basic guidelines, is an efficient way to provide reliable method for gene family annotations.

Planar Al/GaN/Ni Schottky diodes were realized on GaN films deposited on sapphire substrates and characterized in the dark and under illumination. The optoelectronic characteristics of GaNphotodetectors appear largely influenced by structural defects and impurities, which are clearly detected in photocurrent yield measurements. In particular, an exponential increase of the photocurrent is observed and explained in terms of a barrier lowering photoeffect, hence a light-induced shrinking of the space charge region, related to carrier trapping at defects and impurities. Trapping events are also responsible for a dispersive behavior of the AC responsivity with the light chopping frequency. Such effects point out the importance of a proper selection of bias voltage and working frequency for GaNphotodetector operations.

This paper discusses guidelines that emphasize the relevance of short-circuit- and open-circuit-time constant (SCTC and OCTC, respectively) methods in the analysis and design of electronic amplifiers. It is demonstrated that it is only necessary to grasp a few concepts in order to understand that the two short- and open-circuit cases fall into a single case that can be easily addressed by low-pass and high-pass filters duality. Instead of just teaching the methods as ldquorecipesrdquo for frequency-performance systems analysis, SCTC and OCTC can be efficiently explained in basic analog electronic courses so as to elucidate their underlying principles. The discussion presented here will include two analysis and design examples, used to highlight the benefits gained by the approximated analysis technique, as well as a section that examines the accuracy of the technique.

In the last twenty years, erythropoiesis-stimulating agents (ESAs) have improved the management of renal anemia, with significant amelioration of quality of life in patients on hemodialysis. ESAs can be administered both intravenously and subcutaneously. In predialysis chronic kidney disease and in peritoneal dialysis, the administration route is necessarily subcutaneous. In hemodialysis the intravenous route was initially preferred because of the presence of ready vascular access for drug administration. Subsequent studies have demonstrated that the subcutaneous route allowed the achievement of optimal levels of hemoglobin with a reduction of mean administered dose, number of injections, and costs. A few years ago, the finding of a higher risk of pure red cell aplasia associated with subcutaneous administration of epoetin reopened the debate about the route of administration. We here review the studies on the preferable route of administration of epoetin and darbepoetin- alpha, in terms of efficacy and safety, and take a look at future perspectives.

Renal dynamics and morphology were investigated by metabolic, renal micropuncture (RM), and electron microscopy (EM) studies in 50 female rats treated with cyclosporin A (CsA, 40 mg.kg body wt-1.48 h-1) for either 10, 20, or 30 days (groups CsA 10, CsA 20, and CsA 30, respectively); control rats received olive oil (group N). Body weight gain, sodium metabolism, and plasma volume were not altered by CsA administration in any group. GFR was decreased in group CsA 10 vs. group N (-10%, P less than 0.05) and was further impaired in groups CsA 20 and CsA 30 (-45%, P less than 0.01 vs. group N). RM studies showed a significant decrease of single-nephron glomerular filtration rate (SNGFR) in group CsA 30 vs. group N (-26%, P less than 0.01) after the fall of glomerular capillary pressure (Pgc;-8%, P less than 0.05), the increase of afferent arteriole resistance (Ra; +40%, P less than 0.05), and the consequent decrease of glomerular plasma flow (GPF; -28%, P less than 0.05). Thirty days after CsA withdrawal, SNGFR returned to normal values (P less than 0.01 vs. group CsA) as a result of the normalization of Pgc, Ra, and GPF.EM showed only a progressive vacuolation of proximal and distal tubular cells. These data suggest that medium-term administration of CsA is associated with reversible changes in glomerular dynamics and only mild histological lesions.

There are two analogies which justify the comparison between law and game. The notion of constitutive rule occurs in the formulation of both analogies. The paper L'enjeu des règles is devoted to the explication and the implications of the notion of eidetic- constitutive rule. The six main topics dealt with in the paper are : (i) history of the theory of constitutive rules ; (ii) definitions of the notion of eidetic-constitutive rule ; (iii) typology of deontic eidetic-contitutive rules (paradigmatic rules vs. syntagmatic rules) ; (iv) distinction between the notion of eidetic-constitutive rule and the related notion of anankastic-constitutive rule ; (v) discussion of the possibility of antinomies (conflicts) between eidetic-constitutive rules and between anankastic- constitutive rules ; (vi) analysis of the relevance of the theory of eidetic-constitutive rules for deontics, philosophy of law, philosophy of normative language., II y a deux analogies qui justifient la comparaison entre droit et jeu. Dans leur formulation, paraît un concept cardinal de la déontique et de la philosophie du langage normatif : le concept de règle constitutive, en particulier le concept de règle eidético-constitutive. L'essai suivant est consacré à l'explication et aux implications de ce concept. Cet article est constitué par les six phases suivantes : (i) histoire de la théorie des règles constitutives ; (ii) deux définitions du concept de règle eidético-constitutive ; (iii) typologie des règles eidético-constitutives déontiques (règles paradigmatiques vs. règles syntagmatiques) ; (iv) distinction entre le concept de règle eidético-constitutive et le concept de règle anankastico-constitutive ; (v) discussion de la possibilité d'antinomie entre deux règles eidético-constitutives et entre deux règles anankastico-constitutives ; (vi) discussion de la signification des règles eidético-constitutives pour la déontique, pour la philosophie du droit, pour la philosophie du langage normatif., Conte Amedeo G. L'enjeu des règles. In: Droit et société, n°17-18, 1991. Droit et jeu, sous la direction de François Ost et Michel van de Kerchove. pp. 125-146.

The paper decribes the GSPN approach to the performance evaluation of distributed systems. The structural properties and temporal specifications of GSPN are summarized, and application examples are then illustrated, trying to emphasize the methodology to be followed in the model development and validation, rather than the numerical results that can be obtained from the specific models developed in the paper.

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a disorder of sodium and water balance characterized by hypotonic hyponatremia and impaired water excretion in the absence of renal insufficiency , adrenal insufficiency or any recognized stimulus for the antidiuretic hormone (ADH). An inappropriate increase in ADH release of any cause produces hyponatremia by interfering with urinary dilution, thereby preventing the excretion of ingested water. Despite being the most common cause of hyponatremia in hospitalized patients, SIADH remains a diagnosis of exclusion. SIADH should be suspected in any patient with hyponatremia, hyposmolarity, urine osmolality above 100 mosmol/hgH2O, urine sodium concentration usually above 40 mEq/L, and clinical euvolemia. a number of modalities can be used to correct hyponatremia in SIADH, with water restriction and salt administration being the most important. The rate of correction is dependent upon the degree of hyponatremia and the presence or absence of symptoms. Patients with severe neurological symptoms require prompt correction; however, excessively rapid correction should be avoided because it can lead to the late onset of neurological complications from osmotic demyelination.

In chronic kidney disease, blood pressure control is a major aim of therapy to slow down renal disease progression and reduce the cardiovascular risk. Ambulatory blood pressure monitoring is a valid tool to define the prognosis and indicated therapy for hypertension. It allows to detect blood pressure patterns such as the white-coat effect, resulting in a better definition of the cardiovascular risk profile. Description of the circadian pressure rhythm, moreover, may reveal the presence of physiological nocturnal loss (dipping status). Recently, it has been demonstrated that a non-dipping status is associated with a higher risk of end-stage renal disease and more rapid progression of kidney disease independent of blood pressure control. Furthermore, longitudinal studies have demonstrated that a non-dipping status is associated with increased cardiovascular morbidity and mortality in the general population and in hypertensive patients. We have less information on this issue in chronic kidney disease. In this high-risk subgroup of hypertensive patients, it remains ill-defined whether ambulatory blood pressure monitoring predicts cardiovascular outcomes better than in-office measurement.

Many patients affected by chronic kidney disease (CKD) die before reaching endstage renal disease because of cardiovascular disease (CVD). Recent guidelines and position statements have therefore defined CKD as a cardiovascular risk equivalent, and patients in all stages of CKD are considered in the highest risk group for development of CVD. Heart failure (HF) is the main cardiovascular complication that occurs in renal patients and its incidence increases proportionally with the reduction of glomerular filtration rate. In fact, pressure and volume overload, that are inherent to the abnormalities of homeostasis typical of CKD, lead to concentric/eccentric left ventricular hypertrophy (LVH). Initially, LVH is adaptative because energy is spared by maintaining stable wall stress. However, in the long term, LVH becomes maladaptative, inducing systolic and/or diastolic dysfunction that, in turn, lead to symptomatic left ventricular failure. Nowadays, it is well established that several classes of drugs, including reninangiotensin system antagonists, beta blockers and aldosterone antagonists, improve survival in patients with HF. In fact, all major guidelines on HF recommend such drugs as standard therapy. The problem for nephrologists is that the general approach and recommendations for the management of HF in the general population may not be completely safe in renal patients with HF. This review is conducted with the purpose to provide more information on the efficacy and safety of HF therapy in renal patients.

The high potential of P2P infrastructures for enterprise services and applications both on the intranet (e.g. project workgroups) and on the Internet (e.g. B2B exchange) can be fully achieved provided that robust trust and security management systems are made available.

Introduction:Adolescence seems to be a critical period of addiction vulnerability, based on both neurobiological, social, and familiar factors. The earlier onset of behavioural/substance dependence seems to predict greater addiction severity, morbidity, and multiple addictive disorders. The aim of this study was to assess the presence of multiple addictions in an Italian adolescent high-school population.Methods:Data were collected from a sample of 2907 high school students recruited in the area of Barletta (Puglia) and Latina (Lazio). The sample had an average age of 16.69+/-1.89 years. Through different multi-item scales we evaluated different behavioural addictions: Pathological Gambling, Internet Addiction, Compulsive Buying, Sexual Addiction, Relationship Addiction, Mobile Phone Addiction, Exercise Addiction, Work Addiction.Results:the presence of pathological gambling was found in 4.4%, compulsive buying in 8.3%, internet addiction in 1.1%, work addiction in 7.2%, exercise addiction in 6.7% of the subjects. Males showed higher scores (p

Blood pressure (BP) is hardly controlled in chronic kidney disease (CKD). We compared the effect of very low protein diet (VLPD) supplemented with ketoanalogs of essential amino acids (0.35 g/kg/day), low protein diet (LPD, 0.60 g/kg/day), and free diet (FD) on BP in patients with CKD stages 4 and 5. Vegetable proteins were higher in VLPD (66%) than in LPD (48%). LPD was prescribed to 110 consecutive patients; after run-in, they were invited to start VLPD. Thirty subjects accepted; 57 decided to continue LPD; 23 refused either diet (FD group). At baseline, protein intake (g/kg/day) was 0.79+/-0.09 in VLPD, 0.78+/-0.11 in LPD, and 1.11+/-0.18 in FD (P0.0001). After 6 months, protein intake was lower in VLPD than LPD and FD (0.54+/-0.11, 0.78+/-0.10, and 1.04+/-0.21 g/kg/day, respectively; P0.0001). BP diminished only in VLPD, from 143+/-19/84+/-10 to 128+/-16/78+/-7 mm Hg (P0.0001), despite reduction of antihypertensive drugs (from 2.6+/-1.1 to 1.8+/-1.2; P0.001). Urinary urea excretion directly correlated with urinary sodium excretion, which diminished in VLPD (from 181+/-32 to 131+/-36 mEq/day; P0.001). At multiple regression analysis (R2=0.270, P0.0001), BP results independently related to urinary sodium excretion (P=0.023) and VLPD prescription (P=0.003), but not to the level of protein intake. Thus, in moderate to advanced CKD, VLPD has an antihypertensive effect likely due to reduction of salt intake, type of proteins, and ketoanalogs supplementation, independent of actual protein intake.

We have previously demonstrated that dopamine conjugation to glucose allows it to induce therapeutic effects against Parkinson's disease after intravenous administration. In this paper we demonstrate that, unlike dopamine, the prodrug glu-dopamine is a transportable substrate of glucose transporters. Towards this, the effect of glucose-conjugation on the affinity and uptake of dopamine have been assessed in vitro, using human retinal pigment epithelium (HRPE) cells. Glucose transporter-mediated uptake was measured using [(3)H]3-O-methylglucose ([(3)H]3-O-MG) as the tracer. The uptake was found to be rapid and hyperbolically related to its concentrations (K(t)=7.8+/-1.2mM and V(max)=54+/-2 nmol/min mg protein). Inhibition experiments showed that dopamine was able to interact with glucose carriers only when conjugated to glucose (IC(50)=2.6+/-0.6mM). HPLC analysis of HRPE cell extracts showed that both dopamine and the prodrug permeate the cell, but only the uptake of the prodrug is inhibitable by glucose. This confirms that glucose transporters mediate the transport of the prodrug glu-dopamine, but not of dopamine. HRPE cells is therefore proposed as a promising model for in vitro studies involving the glucose transporter-mediated transport of drugs and their conjugates.

Οι τεχνικές υψηλής ανάλυσης απόκτησης και επεξεργασίας επιφανειακών γεωφυσικών δεδομένων εφαρμόζονται ολοένα και περισσότερο στην αρχαιολογία. Στην εργασία αυτή, παρουσιάζονται προκαταρκτικά αποτελέσματα από γεωφυσικές αναλύσεις που στοχεύουν στη διερεύνηση υπόγειων αρχαιολογικών ευρημάτων σε δύο επιλεγμένες περιοχές: στη Θουρία (Πελοπόννησος, Ελλάδα) και στην περιοχή Sibari (Νότια Ιταλία). Στην πρώτη περίπτωση η γεωφυσική προσέγγιση περιλαμβάνει τη συνδυαστική εφαρμογή γεωηλεκτρικών και μαγνητικών μεθόδων και μίας καινοτόμου τομογραφικής ανάλυσης για την αντιστροφή των δεδομένων της ειδικής αντίστασης και των μαγνητικών στοιχείων. Στη δεύτερη περίπτωση, πραγματοποιήθηκαν υψηλής ανάλυσης μαγνητικές μετρήσεις, οι οποίες ερμηνεύτηκαν με εφαρμογή των κατάλληλων φίλτρων. Η εφαρμοσμένη αναστροφή των δεδομένων δίνει τη δυνατότητα παραγωγής αξιόπιστων χωρικών μοντέλων και βελτιώνει την ποιότητα των πληροφοριών των γεωφυσικών μεθόδων. Τα αποτελέσματα που προκύπτουν σε αυτό το αρχικό στάδιο της επεξεργασίας επιβεβαιώνουν αρχαιολογικές υποθέσεις σχετικά με ης περιοχές έρευνας, ενώ παράλληλα με τη χρήση των γεωφυσικών μεθόδων επιτυγχάνεται μείωση του χρόνου και των δαπανών κατά την αρχαιολογική έρευνα., High resolution techniques for data acquisition and processing procedures are increasingly applied in near-surface geophysics for archaeology. In this paper we present the preliminary results of two geophysical measurements campaigns aimed to the investigation of buried remains in the archaeological sites of Θουρία (Péloponnèse, Hellas) and Sibari (Southern Italy). In the first field survey the geophysical approach involved the integrated application of the geoelectrical and magnetic methods and an innovative tomographic analysis for the inversion of both resistivity and magnetic data. In the second case, we carried out high resolution magnetic measurements, interpreted by means of the use of an appropriate filtering procedure. The applied data inversion allows us to provide reliable space patterns of the most probable specific target boundaries, improving the information quality of geophysical methods. The results obtained at this early stage of data processing confirm some archaeological hypothesis about the investigated areas and confirm that the use of integrated geophysical methods allows the archaeologists to reduce the time and the costs of their surveys.

In this contribution, we describe an advanced mixed-mode physics-based device simulator applied to the estimation of the noise properties of microwave mixers. The drift-diffusion model, and a proper set of circuit equations describing the device embedding network, are solved in the frequency domain with the harmonic balance approach. The cyclostationary device noise properties are then numerically estimated, and used to calculate the system mixer noise performances. An example of application to a downconversion GaAs MESFET mixer is reported to demonstrate the simulator capabilities.

Guidelines have indicated the achievement of blood pressure target (BP130/80 mmHg) as a priority in the conservative treatment of chronic kidney disease (CKD), but the current implementation of these recommendations in clinical practice is unknown.We assessed control rates, treatment and clinical correlates of hypertension in 1201 adult non-dialyzed CKD patients followed up by a nephrologist for at least 6 months.Estimated glomerular filtration rate (GFR) was 32 (SD 15) mL/min/1.73 m2. BP target was not achieved in 88% of patients (95% confidence interval (95% CI): 86-90%). In 84% of patients, BP levels were also above the target at the first visit to the nephrology unit 4.5 yrs previously. The risk of not achieving BP target during the nephro-logy follow-up was associated with older age (odds ratio (OR): 1.24, 95% CI 1.06-1.45, p=0.008), diabetes (OR: 2.25, 95% CI 1.20-4.20, p=0.011), and the duration of hypertension (OR: 1.13, 95% CI 1.02-1.24, p=0.016). Among patients with uncontrolled BP, about 70% received multidrug antihypertensive therapy including renin-angiotensin system (RAS) inhibitors; conversely, diuretic treatment was prescribed in a minority of patients (37%), and at insufficient doses in half the cases, despite the insufficient implementation of a low salt diet (18%).BP target was not reached in most CKD patients routinely seen in the renal clinics. The main barrier to guideline implementation is possibly the inadequate treatment of extracellular volume expansion despite the large prevalence of factors, such as older age and diabetes, which further enhance the intrinsic BP salt sensitivity of CKD.

In this work we present a new scheme for the realization of a beam profiler for excimer laser UV-light. The sensor is based on a single pixel, large area, photoconductor scanned by a red laser. The sensing principle involves the trapping occurring in the active film after the exposition to the UV radiation. Due to this effect the photoresponse to the red laser is enhanced in the regions exposed to the UV radiation, proportionally to the intensity of the overgap radiation absorbed by the active material. With this scheme, the sensor does not require the complex interconnections and reading circuitry that are needed by image sensors realized as photoconductor arrays. An ArF (193 nm) excimer laser was used to shine light on the devices, whose surface was then scanned by a red (650 nm) semiconductor laser. The current flowing through the detector was amplified and recorded by a digitizing oscilloscope (LeCroy WP690).

Three radiation detectors based on polycrystalline diamond films with different thickness and resistivity, obtained by microwave chemical vapor deposition, were tested to assess their suitability for relative dosimetry of photon and electron beams supplied by clinical linear accelerators. All samples showed a linear response as a function of the absorbed dose. The sensitivity per unit of detector sensitive volume spanned between 7 and 43 nC Gy(-1) mm(-3) with an applied electric field of 40 kV/cm. The dose rate dependence was evaluated following the Fowler theory and delta coefficient values between 0.95 and 1.00 were found for the three samples when polarized at 40 kV/cm. Percentage depth dose curves, output factors, and normalized dose profiles were determined for 6 and 10 MV photon beams and for 6 and 15 MeV electron beams. The results obtained with the diamond detectors were in good agreement with those obtained by reference detector measurements [all the data were within the experimental uncertainty of 1% (1sigma)].

In the 1960s, about 10% of hemodialysis (HD) patients had hypertension; the current percentage of hypertensive patients has risen to 70-75%. The scarce implementation of low-salt diets and the increment of dialysate sodium concentration aimed at ameliorating treatment tolerability are the main causes of the currently poor hypertension control. Considerable sodium intake activates a vicious circle: an increase in serum osmolarity, greater thirst and greater water intake, high inter-dialytic weight gains, need for large ultrafiltration rates, more frequent episodes of intradialytic hypotension, failure to achieve dry weight, progressive extra-cellular volume (ECV) expansion, and finally, blood pressure (BP) increase. Therefore, many studies have pointed out the importance of a low-salt diet in HD; it has been proven that the normalization of BP and ECV overload with a low-salt diet is associated with left ventricular hypertrophy regression and diastolic dysfunction improvement. Preparing meals with fresh foods, using spices, avoiding salt when cooking, and drastically limiting salty foods reduce dietary sodium down to about 6 g/day. Sodium intake during inter-dialytic periods can easily be assessed by measuring the changes in serum sodium concentration and in body weight.

Service-Oriented Architectures (SOAs) are rapidly becoming the key approach for achieving new levels of interoperability and scalability in the development of Grid applications. Within SOA solutions, current approaches for advertising service providers and for allowing prospective clients to discover them are mostly based on centralized registries. Envisioning Virtual Organizations in which all participants are both resource providers and consumers, in a peer-to-peer fashion, seems to be an appealing approach.In this paper we propose the Service-oriented Peer-to-Peer Architecture (SP2A), a framework enabling peer-to-peer resource sharing in Grid environments. Resources are not directly exposed but can be accessed through Resource Provision Services, whose semantically enriched interfaces are published in the network. The framework has been implemented as a Java API, which currently supports a number of important technologies such as JXTA (peer-to-peer routing), Web Services (service deployment), and OWL-S (semantic description of services).

This contribution is aimed at describing the available techniques for simulating trap-assisted generation recombination noise in electron devices. We consider physics-based models, where carrier transport equations are complemented by a set of rate equations, one for each trap energy level included in the model, expressing charge conservation. To the aim of noise analysis, such rate equations include stochastic Langevin sources representing level occupancy fluctuations, whose statistical properties are known from basic physical analysis. A generalization of the standard Green's function technique to the physics-based noise analysis can be then exploited to propagate the internal fluctuations to the device terminals, in order to evaluate the correlation matrix of the external noise generators. With reference to a simple device, a superposition of noninteracting trap levels with a proper distribution of timeconstants is shown to yield a 1/f spectrum on a prescribed frequency range. In large-signal operation the fundamental white noise fluctuations are amplitude modulated by the periodic device working point and converted into cyclostationary fluctuations. The cyclostationary internal noise is then propagated to the device terminals by means of proper Green's functions that also involve noise frequency conversion. The same device discussed in small-signal operation is simulated in cyclostationary conditions, therefore demonstrating the upconversion of 1/f noise from baseband to the steady-state harmonics.

Most cases of ARF are secondary to volume depletion. In the literature, very few scientific publications address the problem of what to do when confronted with such a patient. As regarding the diagnosis of hypovolemia, an accurate history and physical examination can help to determine both the presence and etiology of volume depletion; postural hypotension (decrement in systolic blood pressure of more than 20 mmHg after standing from the supine position), associated with a pulse increment of 30 beats/min or more and dizziness are specific symptoms of hypovolemia. Laboratory indices are useful to diagnose volume depletion, but their interpretation is not simple, and they may not be available in the non-nephrologic environment. Fluid replacement therapy in hypovolemia is largely dependent upon the type of fluid that has been lost and concurrent electrolytic and acid-base disorders. Patients with hypernatremia and volume depletion should receive mild hypotonic solutions, whereas those with hyponatremia and hypovolemia should receive mild hypertonic solutions. The entity of reinfusion depends on daily losses. Conversely, monitoring of body weight can be considered an adequate index of fluid balance. Concerning the treatment of ARF, the use of loop diuretics in the early phases of pre-renal ARF decrease oxygen consumption in the tubular cells by inhibiting transcellular sodium transport, therefore preventing or limiting ischemic cell injury. The use of loop diuretics should also be evaluated in intermediate syndrome and ischemic NTA where diuretics can, respectively, reduce renal ischemia and convert oliguric ARF into the non-oliguric form.

Construction of GSPN models of complex systems is a difficult task that often demands significant expertise. Faithful representation of detailed behavioral semantics and overall correctness usually require a significant number of iterations and refinements. This modeling effort is substantially hindering widespread application of Petri net based techniques to ever complex systems. One of the many application areas where this modeling problem arises is distribution of computation workload onto concurrent MIMD architectures. An approach based on the automatic generation of GSPN models for workload mapping on concurrent architectures is described. The methodology is based on the synthesis of a net starting from a precedence graph of the computation. The construction of a complete net modeling the MIMD architecture under a specified workload is possible for a given set of architectures. Nets generated by the synthesis process exhibit higher complexity than manually generated ones, but this is not a serious drawback since net solutions and performance estimates can be derived using standard analysis tools (GreatSPN). >

The application described here concerns the detection and the real-time tracking of submarine pipelines from a sequence of underwater images acquired from TV-cameras mounted on a remote operated vehicle (ROV). The problem involves both perception and robotics, in that sensory-motion data are to be acquired and dynamically used for subsequent actions by the system. The basic processing concerns the extraction of the pipe contours which are returned as two straight lines. Motion effects on acquired images have been reduced using a Kalman filter for integrating multiple measurements over time. The filter, positioned at the output of the image processing system improves the precision in the computation of the straight line equations with a little overload. This work is originated from the interest of Snamprogetti in enhancing the level of automation in submarine pipeline inspection.

In this paper we describe a sonar based, collision avoidance module for autonomous underwater vehicle, developed as part of a more complex navigation and guidance system. Its main features are the use of Kalman filters in evaluating both the motion of the detected obstacles and the risk of collision, and the possibility of working at two different levels of abstraction, according to the characteristics of the situation.

This paper describes a complete 6-year project, starting from its theoretical basis up to the hardware and software system implementation, and to the description of its future evolution. The main goal of the project is to develop a subsystem that operates as a processing unit attached to a standard workstation and in perspective as a low-cost low-sized specialized embedded system devoted to low level image analyses and cellular neural networks emulation. The architecture has been extensively used for basic low level image analysis tasks up to optical flow computation and feature tracking, showing encouraging performances even in the first prototype version. >

The problem considered in this paper consists in decoupling a disturbance from the output of a dynamical systems with coefficients in a principal ideal domain, by means of a dynamic state feedback. Using geometric methods, necessary and sufficient conditions for the decouplability are obtained. >

Designing a control system for an underwater remotely operated vehicle (ROV) presents various problems: the ROV dynamics is described by a strongly nonlinear model; this model is characterized by uncertain parameters; unmeasurable disturbances are present. In the paper, the robust technique known as variable (VSS) control or sliding mode control (SMC) has been used, in order to solve the above mentioned problems for a specific ROV model. The control problem that has been considered consists in tracking a given trajectory and the control variables chosen are the electrical currents that drive the four vehicle propellers: this choice, although it gives rise to a model that is nonlinear with respect to the control variables, is motivated by the fact that the resulting controller can take into account possible parametric variations in the relationship between thrusts and electrical currents. The performances of the controllers has been tested by means of suitable simulations, showing the effectiveness of the adopted control technique. Moreover, the possibility of obtaining the information necessary for synthesizing the control law by means of visual data is discussed. >

Describes a GSPN-based approach to performance evaluation of parallel MIMD architectures with mesh interconnection schemes. The analysis considers regular computational structures in which data exchange and inter-process synchronization require communication only among processors that are physically connected. The effectiveness of the modeling technique for this class of architectures is shown through examples considering both the effect of the interaction policies among processes and the benefit of multitrasking on the global efficiency of the architecture. >

The aim of this paper is to present an overview of the geometric approach to the study of dynamical systems with coefficients in a ring and, in particular, to discuss the most recent results concerning the noninteracting control problems it has produced. The basic notions of the geometric approach in the framework of systems with coefficients in a ring and their main features are described and illustrated, together with the computational aspects. Applications to problems concerning delay-differential systems are discussed.

The decoupling problem by static state feedback for a system with coefficients in a ring is investigated using a geometric approach. The notion of precontrollability submodules, which captures the geometric aspects of the notion of controllability in the present context, is introduced and used for stating solvability conditions to the decoupling problem for a system with coefficients in a Noetherian ring. This result extends and improves previous results concerning systems with coefficients in a principal ideal domain.

The aim of this paper is to report on the tailoring of the physical properties of polycrystalline CVD diamond in order to fulfil the requirements of radiotherapy dosimeters. A very simple device geometry has been used to study the electronic response of the polycrystalline CVD layers and results achieved with a 6 MV bremsstrahlung X-ray beam delivered by a linear accelerator are presented and discussed.

Recently introduced "SIMD on registers" extensions to commodity microprocessors instruction sets promise (according to the makers) high potential speed-ups for multimedia processing tasks. This paper introduces the complex programming model of MMX/SSE extensions and discusses how the achievement of an effective performance increase over sequential code is no easy task also due to a poor software support. Experiences gained on two real-time image processing projects helped defining a programming methodology and evaluating the tradeoffs to obtain substantial speed-ups with MMX/SSE code.

The performance of 4 constructed wetlands designed by IRIDRA Srl and operating in Tuscany (central Italy) has been monitored during the last three years. The 4 treatment systems have different sizes and characteristics: one single stage secondary treatment (150 p.e.); two secondary treatment plants with effluent reuse: one small (60 p.e) and the other big (350 p.e.); a tertiary treatment of effluents from an activated sludge plant with high hydraulic load fluctuation (5-500 p.e.). Due to geographical and economic constraints the four systems have high hydraulic and organic loading rates, neverthless the systems show very good removal performance of COD (62-95%), especially the ones with higher inflow COD concentrations (87-95%). Interesting results concerning also removal percentage of MBAS (42-88%) and ammonium (42-85%) were obtained, even though NH4+ concentration in the outflows of some of the plants, doesn't always comply with Italian quality standards.

The paper introduces generalized stochastic Petri nets models for the description and the analysis of the performance of a video on demand service. We present simple models of the server and briefly discuss how this methodology can be useful in order to compare the effectiveness of different disk caching policies. Numerical results show the relative performances of some different choices in a multiclient environment.

The dialytic management of hyper-phosphoremia, which is inadequate because of insufficient intra-dialytic removal of phosphate (P), is further limited by PDR-P, i.e. the significant increase in serum P levels during the early postdialytic period. Patients and methods. To investigate the effects of enhanced P removal by haemodiafiltration on the inter-dialytic phosphoremia, we studied 12 uremic patients that were switched, with cross-over randomised modality, to a single session of standard hemodialysis (HD) and hemodiafiltration (HDF) (Acute Study). Blood samples were obtained before the treatment, at the end (T0), after 30, 60, 90 and 120 minutes, and at 24, 48 and 68 hours. During both dialytic treatments the whole effluent dialysate was collected to evaluate the intradialytic removal of P. Thereafter, patients were randomised to receive either HD or HDF for three months, in the presence of constantly similar Kt/V, food intake and dose of phosphate binder (Chronic Study).Acute Study. Compared to HD, P removal in HDF was about 44% greater in the presence of identical predialytic P levels (6.0+/-0.2 and 5.9+/-0.4 mg/dl) and Kt/V (1.35+/-0.06 and 1.34+/-0.05); however, the inter-dialytic decline of serum P levels did not differ (-50+/-3% versus -42+/-3%, p=0.098). In HDF, PDR-P was faster (30 min versus 90 min) and better (at T120: +69+/-6% versus +31+/-4%, p0.001). The higher P levels were maintained throughout the inter-dialytic period whereas Ca x P changed in parallel. Chronic Study. During the three months, pre-dialytic serum P diminished in HDF (from 5.8+/-0.2 to 4.4+/-0.3 mg/dl, p0.05), while it remained unchanged in HD. A similar pattern of changes was detected in Ca x P.Enhancement of P removal, acutely amplifies the extent of PDR-P, but allows better control of Ca-P homeostasis in the medium term. This effect is likely to be dependent on the enhanced mobilisation of phosphate from a deep compartment.

very year, in the United States alone, nearly 15,000 patients are diagnosed with multiple myeloma (MM) and at any given time there are about 40,000 patients living with the disease, with most patients eventually dying of disease progression. Accurate predictive and prognostic models are needed for the better management of patients. Predictive factors are those that permit estimation of likelihood of response to therapy while prognostic factors allow for an estimation of likelihood of survival time.At present there is no clear distinction between predictive and prognostic factors in MM, and thus most studies have focused on the use of prognostic factors. In this review we will try to discuss some of the most relevant prognostic factors currently used.This review is not intended to be a comprehensive analysis, but will rather focus on some of the most relevant and novel ones.MM is a heterogenous disorder and it is likely that many variants exist, but there is no generally accepted classification system that can predict reliably the expected outcome. There are some patients for whom novel treatment may be chosen due to poor prognostic features, while others may do reasonably well with currently available strategies, due to their longer expected survival. Here we review the relation between laboratory features and prognosis in MM. However, we will also review other factors including characteristics unique to the malignant clone, features reflecting or affecting tumor burden, and host features.