Tecniche di graph mining per l'analisi di reti sociali

La tesi presenta il problema dell’estrazione di conoscenza da reti sociali utilizzando tecniche di graph mining (GM). In particolare si propongono soluzioni per la creazione di un indice di clustering e la ricerca di pattern in un grafo

Deep p-Ring Trench Termination: An Innovative and Cost-Effective Way to Reduce Silicon Area

A new type of high voltage termination, namely the “deep p-ring trench” termination design for high voltage, high power devices is presented and extensively simulated. Termination of such devices consumes a large proportion of the chip size; the proposed design concept not only reduces the termination silicon area required, it also removes the need for an additional mask as is the case of the traditional p+ ring type termination. Furthermore, the presence of the p-ring under and around the bottom of the trench structure reduces the electric field peaks at the corners of the oxide which results in reduced hot carrier injection and improved device reliabilit

Quantum-well-laser mirror degradation investigated by microprobe optical spectroscopy

A study of facet degradation of InGaAs quantum well lasers is reported. We tune up a Raman and photoluminescence micro-probe technique for determining the crystal structure and the temperature profile of the cladding layer, in steps of approximately 1 micrometer, with a temperature resolution better than 1 degree Kelvin. The cladding layer composition and cross- section temperature profile have been monitored during operation. A clear correlation between the facet degradation and the type of protective coating is found

Problematic mobile phone use in adolescence:a cross-sectional study

Aim: In recent years, mobile phone use has become increasingly common among Italian youth, while a growing scientific literature has been identifying the occurrence of a problematic mobile phone use which seems to share some features of other conditions often referred to as behavioural addictions. The study aimed to assess the prevalence of problematic mobile phone use in a population of Italian adolescents and its association with other behavioural addictions. Subjects and methods: The Mobile Addiction Test (MAT) was administered to 2,790 high school students from Barletta, an Italian town, together with the South Oaks Gambling Screen-Revised for Adolescents (SOGS-RA), the Compulsive Buying Scale (CBS), the Internet Addiction Test (IAT), the Exercise Addiction Inventory (EAI), the Work Addiction Risk Test (WART). Results: MAT scores fitted a Gaussian distribution model. Scores ≥ 17 was found as a cut-off value over which identifying problematic mobile phone users. Overall prevalence of problematic mobile phone use was 6.3%; this condition was associated with other behavioural addictions like compulsive buying. Conclusion: Problematic mobile phone use in adolescence should become a public health issue, and it could be a cause of health problems and social costs. © 2011 Springer-Verlag

Apparatus for simultaneous DLS-SANS investigations of dynamics and structure in soft matter

Dynamic Light Scattering (DLS) and Small-Angle Neutron Scattering (SANS) are two key tools with which to probe the dynamic and static structure factor, respectively, in soft matter. Usually DLS and SANS measurements are performed separately, in different laboratories, on different samples and at different times. However, this methodology has particular disadvantages for a large variety of soft materials which exhibit high sensitivity to small changes in fundamental parameters such as waiting times, concentration, pH, ionic strength, etc. Here we report on a new portable DLS-SANS apparatus that allows one to simultaneously measure both the microscopic dynamics (through DLS) and the static structure (through SANS) on the same sample. The apparatus has been constructed as a collaboration between two laboratories, each an expert in one of the scattering methods, and was commissioned on the \textit{LOQ} and \textit{ZOOM} SANS instruments at the ISIS Pulsed Neutron \& Muon Source, U.K

Clinical use of polymerase chain reaction performed on peripheral blood and bone marrow samples for the diagnosis and monitoring of visceral leishmaniasis in HIV-infected and HIV-uninfected patients: a single-center, 8-year experience in Italy and review of the literature

Background. To overcome some of the limitations of conventional microbiologic techniques, polymerase chain reaction (PCR)–based assays are proposed as useful tools for the diagnosis of visceral leishmaniasis. Patients and methods. A comparative study using conventional microbiologic techniques (i.e., serologic testing, microscopic examination, and culture) and a Leishmania species–specific PCR assay, using peripheral blood and bone marrow aspirate samples as templates, was conducted during an 8-year period. The study cohort consisted of 594 Italian immunocompetent (adult and pediatric) and immunocompromised (adult) patients experiencing febrile syndromes associated with hematologic alterations and/or hepatosplenomegaly. Identification of the infecting protozoa at the species level was directly obtained by PCR of peripheral blood samples, followed by restriction fragment–length polymorphism analysis of the amplified products, and the results were compared with those of isoenzyme typing of Leishmania species strains from patients, which were isolated in vitro. Results. Sixty-eight patients (11.4%) had a confirmed diagnosis of visceral leishmaniasis. Eleven cases were observed in human immunodeficiency virus (HIV)–uninfected adults, 20 cases were observed in HIV-infected adults, and the remaining 37 cases were diagnosed in HIV-uninfected children. In the diagnosis of primary visceral leishmaniasis, the sensitivities of the Leishmania species–specific PCR were 95.7% for bone marrow aspirate samples and 98.5% for peripheral blood samples versus sensitivities of 76.2%, 85.5%, and 90.2% for bone marrow aspirate isolation, serologic testing, and microscopic examination of bone marrow biopsy specimens, respectively. None of 229 healthy blood donors or 25 patients with imported malaria who were used as negative control subjects had PCR results positive for Leishmania species in peripheral blood samples (i.e., specificity of Leishmania species– specific PCR, 100%). PCR and restriction fragment–length polymorphism analysis for Leishmania species identification revealed 100% concordance with isoenzyme typing in the 19 patients for whom the latter data were available. Conclusions. PCR assay is a highly sensitive and specific tool for the diagnosis of visceral leishmaniasis in both immunocompetent and immunocompromised patients and can be reliably used for rapid parasite identification at the species level