Search results for " Onde"

EFFETTI IDRO-MORFODINAMICI DI UNA BARRIERA SOFFOLTA IN GEOTESSUTO

Nel periodo di dottorato si è valutato se queste barriere possono rappresentare delle valide alternative in termini idromorfodinamici alle barriere tradizionali per la protezione delle spiagge interessate da fenomeni di erosione costiera. La barriera è costituita da sacchi di geotessuto riempiti con sabbia prelevata in zone limitrofe all’area di intervento, preferibilmente cave marine presenti a largo. Le indagini sperimentali sono state condotte in scala in una canaletta marittima di laboratorio con fondo mobile sabbioso, considerando una disposizione dei sacchi ordinata (cioè disposti tutti longitudinalmente al canale e accuratamente assestati) ed una alla rinfusa; per la disposizione ord…

The relationship between Polypharmacy and Trajectories of Cognitive Decline in People with Dementia: a large representative cohort study

2019

Polypharmacy, defined through the number of medications prescribed, has been linked to a range of adverse health outcomes in people with dementia. It is however unclear whether a numerical threshold of concurrently prescribed drugs is a suitable predictor for cognitive decline. We aimed to test associations between polypharmacy and both short-term (six months) and long-term (three years) cognitive trajectories in patients with incident dementia. Using data from a large mental health and dementia care database in South London, a cohort of 12,148 patients (mean age = 80.7 years, 61.1% female, mean MMSE = 18.6) clinically diagnosed with dementia was identified. We determined the number of medi…

Vaccine hesitancy and refusal among parents: An international ID-IRI survey

2022

Introduction: Although vaccines are the safest and most effective means to prevent and control infectious diseases, the increasing rate of vaccine hesitancy and refusal (VHR) has become a worldwide concern. We aimed to find opinions of parents on vaccinating their children and contribute to available literature in order to support the fight against vaccine refusal by investigating the reasons for VHR on a global scale.Methodology: In this international cross-sectional multicenter study conducted by the Infectious Diseases International Research Initiative (ID-IRI), a questionnaire consisting of 20 questions was used to determine parents' attitudes towards vaccination of their children.Resul…

Relationship between the Clinical Frailty Scale and short-term mortality in patients ≥ 80 years old acutely admitted to the ICU: a prospective cohort…

2021

Abstract Background The Clinical Frailty Scale (CFS) is frequently used to measure frailty in critically ill adults. There is wide variation in the approach to analysing the relationship between the CFS score and mortality after admission to the ICU. This study aimed to evaluate the influence of modelling approach on the association between the CFS score and short-term mortality and quantify the prognostic value of frailty in this context. Methods We analysed data from two multicentre prospective cohort studies which enrolled intensive care unit patients ≥ 80 years old in 26 countries. The primary outcome was mortality within 30-days from admission to the ICU. Logistic regression models for…

Multi-focus image fusion using local variability

2018

In this thesis, we are interested in the multi-focus image fusion method. This technique consists of fusing several captured images with different focal lengths of the same scene to obtain an image with better quality than the two source images. We propose an image fusion method based on Laplacian pyramid technique using Discrete Wavelet Transform (DWT) as a selection rule. We then develop two multi-focus image fusion methods based on the local variability of each pixel. It takes into account the information in the surrounding pixel area. The first method is to use local variability as an information in the Dempster-Shafer theory. The second method uses a metric based on local variability. …

Génération et interfaçage de lumière à photon unique et contrôle de la dynamique atomique ultra-rapide pour l’information quantique

2010

We develop a robust and realistic mechanism for the generation of indistinguishable single-photon (SP) pulses with identical frequency and polarization. They are produced on demand from a coupled double-Raman atom-cavity system driven by a sequence of laser pump pulses. This scheme features a high efficiency, the ability to produce a sequence of narrow-band SP pulses with a delay determined only by the pump repetition rate, and simplicity of the system free from complications such as repumping process and environmental dephasing. We propose and analyze a simple scheme of parametric frequency conversion for optical quantum information in cold atomic ensembles. Its remarkable properties are m…

Oscillazioni della linea di riva in presenza di frangimento

2009

Tendinopatie calcifiche di spalla: Trattamento con onde d’urto extracorporee.

2009

Revisione critica del modello SMB attraverso un caso studio nel mediterraneo

2010

Studio numerico e sperimentale sulla generazione degli ultrasuoni tramite sorgente laser puntiforme

2011

An experimental and numerical study on the ultrasonic fields generated in metals by a point laser source has been done. Energy and profile of the beam, pulse duration, extent and shape of the irradiated area affect amplitude, frequency and directionality of the ultrasonic waves. The study has been developed for the thermoelastic regime, where the laser radiation with low energy density limits the amplitude of ultrasounds and therefore the sensitivity in detecting the defects in extended bodies. By controlling some parameters the signal-to-noise ratio can be increased. The experimental study has been conducted by varying the impact area, the distribution of the beam energy in the impact area…