Mixer a reiezione per applicazioni WLAN a 5-6 GHz

Gli attuali sviluppi delle tecnologie dell’informazione e comunicazione (ICT), ed in particolare di tutte le applicazioni mobili (cellulari ed applicazioni Wireless) di nuova generazione, vanno nella direzione di un miglioramento e rinnovamento dei servizi offerti all’utente. Le tendenze degli ultimi anni sono orientate verso sistemi di comunicazione LAN (Local Area Network) e WLAN (WirelessLAN). Gli avanzati livelli di qualità raggiunti dagli standard di riferimento ed il continuo progresso tecnologico nel settore microelettronico sono già in grado di garantire l’accesso ad Internet senza cavi o ad altre applicazioni wireless che richiedano un trasferimento di dati ad alta velocità. L’obiettivo dei produttori, e quindi delle attività di ricerca dei progettisti, è quello di diffondere e rendere accessibili questi servizi “locali” ad un numero sempre maggiore di utenti. In questo contesto si inserisce la domotica: le applicazioni della microelettronica in ambiente domestico e negli uffici sono molteplici e si prevede perciò un mercato in continua espansione e diffusione. La finalità della domotica è quindi un miglioramento della qualità della vita ed un aumento dei comfort, sia in spazi privati che pubblici; infatti, le possibili applicazioni spaziano dal controllo remoto di elettrodomestici, al monitoraggio a distanza di sensori negli impianti di sorveglianza, alla capacità di realizzare sistemi di ausilio ad anziani o portatori di handicap, alla flessibilità offerta sia ai privati che alle aziende per accessi alla rete globale, alla gestione di apparecchiature ospedaliere. Questo lavoro di tesi ha come obiettivo il progetto e la successiva integrazione in tecnologia BiCMOS al SiGe di un Mixer a reiezione della frequenza immagine per applicazioni WLAN a 5-6 GHz e si inserisce in un contesto più ampio: il progetto "COFIN". Tale lavoro di ricerca si propone di realizzare un transceiver a Radiofrequenza completamente integrato per applicazioni wireless domotiche

A machine-learning based bio-psycho-social model for the prediction of non-obstructive and obstructive coronary artery disease

Background: Mechanisms of myocardial ischemia in obstructive and non-obstructive coronary artery disease (CAD), and the interplay between clinical, functional, biological and psycho-social features, are still far to be fully elucidated. Objectives: To develop a machine-learning (ML) model for the supervised prediction of obstructive versus non-obstructive CAD. Methods: From the EVA study, we analysed adults hospitalized for IHD undergoing conventional coronary angiography (CCA). Non-obstructive CAD was defined by a stenosis < 50% in one or more vessels. Baseline clinical and psycho-socio-cultural characteristics were used for computing a Rockwood and Mitnitski frailty index, and a gender score according to GENESIS-PRAXY methodology. Serum concentration of inflammatory cytokines was measured with a multiplex flow cytometry assay. Through an XGBoost classifier combined with an explainable artificial intelligence tool (SHAP), we identified the most influential features in discriminating obstructive versus non-obstructive CAD. Results: Among the overall EVA cohort (n = 509), 311 individuals (mean age 67 ± 11 years, 38% females; 67% obstructive CAD) with complete data were analysed. The ML-based model (83% accuracy and 87% precision) showed that while obstructive CAD was associated with higher frailty index, older age and a cytokine signature characterized by IL-1β, IL-12p70 and IL-33, non-obstructive CAD was associated with a higher gender score (i.e., social characteristics traditionally ascribed to women) and with a cytokine signature characterized by IL-18, IL-8, IL-23. Conclusions: Integrating clinical, biological, and psycho-social features, we have optimized a sex- and gender-unbiased model that discriminates obstructive and non-obstructive CAD. Further mechanistic studies will shed light on the biological plausibility of these associations. Clinical trial registration: NCT02737982

Frequency of Left Ventricular Hypertrophy in Non-Valvular Atrial Fibrillation

Left ventricular hypertrophy (LVH) is significantly related to adverse clinical outcomes in patients at high risk of cardiovascular events. In patients with atrial fibrillation (AF), data on LVH, that is, prevalence and determinants, are inconsistent mainly because of different definitions and heterogeneity of study populations. We determined echocardiographic-based LVH prevalence and clinical factors independently associated with its development in a prospective cohort of patients with non-valvular (NV) AF. From the "Atrial Fibrillation Registry for Ankle-brachial Index Prevalence Assessment: Collaborative Italian Study" (ARAPACIS) population, 1,184 patients with NVAF (mean age 72 \ub1 11 years; 56% men) with complete data to define LVH were selected. ARAPACIS is a multicenter, observational, prospective, longitudinal on-going study designed to estimate prevalence of peripheral artery disease in patients with NVAF. We found a high prevalence of LVH (52%) in patients with NVAF. Compared to those without LVH, patients with AF with LVH were older and had a higher prevalence of hypertension, diabetes, and previous myocardial infarction (MI). A higher prevalence of ankle-brachial index 640.90 was seen in patients with LVH (22 vs 17%, p = 0.0392). Patients with LVH were at significantly higher thromboembolic risk, with CHA2DS2-VASc 652 seen in 93% of LVH and in 73% of patients without LVH (p <0.05). Women with LVH had a higher prevalence of concentric hypertrophy than men (46% vs 29%, p = 0.0003). Logistic regression analysis demonstrated that female gender (odds ratio [OR] 2.80, p <0.0001), age (OR 1.03 per year, p <0.001), hypertension (OR 2.30, p <0.001), diabetes (OR 1.62, p = 0.004), and previous MI (OR 1.96, p = 0.001) were independently associated with LVH. In conclusion, patients with NVAF have a high prevalence of LVH, which is related to female gender, older age, hypertension, and previous MI. These patients are at high thromboembolic risk and deserve a holistic approach to cardiovascular prevention