Enabling Blocks for Integrated CMOS UWB Transceivers

The last decades have seen an unrivaled growth and diffusion of mobile telecommunications. Several standards have been developed to this purposes, from GSM mobile phone communications to WLAN IEEE 802.11, providing different services for the the transmission of signals ranging from voice to high data rate digital communications and Digital Video Broadcasting (DVB). In this wide research and market field, this thesis focuses on Ultra Wideband (UWB) communications, an emerging technology for providing very high data rate transmissions over very short distances. In particular the presented research deals with the circuit design of enabling blocks for MB-OFDM UWB CMOS single-chip transceivers, namely the frequency synthesizer and the transmission mixer and power amplifier. First we discuss three different models for the simulation of chargepump phase-locked loops, namely the continuous time s-domain and discrete time z-domain approximations and the exact semi-analytical time-domain model. The limitations of the two approximated models are analyzed in terms of error in the computed settling time as a function of loop parameters, deriving practical conditions under which the different models are reliable for fast settling PLLs up to fourth order. Besides, a phase noise analysis method based upon the time-domain model is introduced and compared to the results obtained by means of the s-domain model. We compare the three models over the simulation of a fast switching PLL to be integrated in a frequency synthesizer for WiMedia MB-OFDM UWB systems. In the second part, the theoretical analysis is applied to the design of a 60mW 3.4 to 9.2GHz 12 Bands frequency synthesizer for MB-OFDM UWB based on two wide-band PLLs. The design is presented and discussed up to layout level. A test chip has been implemented in TSMC CMOS 90nm technology, measured data is provided. The functionality of the circuit is proved and specifications are met with state-of-the-art area occupation and power consumption. The last part of the thesis deals with the design of a transmission mixer and a power amplifier for MB-OFDM UWB band group 1. The design has been carried on up to layout level in ST Microlectronics 65nm CMOS technology. Main characteristics of the systems are the wideband behavior (1.6 GHz of bandwidth) and the constant behavior over process parameters, temperature and supply voltage thanks to the design of dedicated adaptive biasing circuits.

The Integrated European Project "GEHA - GEnetics of Healthy Aging": recruitment, health status assessment and survival of the Italian 90+ sibpairs

The present study is part of the EU Integrated Project “GEHA – Genetics of Healthy Aging” (Franceschi C et al., Ann N Y Acad Sci. 1100: 21-45, 2007), whose aim is to identify genes involved in healthy aging and longevity, which allow individuals to survive to advanced age in good cognitive and physical function and in the absence of major age-related diseases. Aims The major aims of this thesis were the following: 1. to outline the recruitment procedure of 90+ Italian siblings performed by the recruiting units of the University of Bologna (UNIBO) and Rome (ISS). The procedures related to the following items necessary to perform the study were described and commented: identification of the eligible area for recruitment, demographic aspects related to the need of getting census lists of 90+siblings, mail and phone contact with 90+ subjects and their families, bioethics aspects of the whole procedure, standardization of the recruitment methodology and set-up of a detailed flow chart to be followed by the European recruitment centres (obtainment of the informed consent form, anonimization of data by using a special code, how to perform the interview, how to collect the blood, how to enter data in the GEHA Phenotypic Data Base hosted at Odense). 2. to provide an overview of the phenotypic characteristics of 90+ Italian siblings recruited by the recruiting units of the University of Bologna (UNIBO) and Rome (ISS). The following items were addressed: socio-demographic characteristics, health status, cognitive assessment, physical conditions (handgrip strength test, chair-stand test, physical ability including ADL, vision and hearing ability, movement ability and doing light housework), life-style information (smoking and drinking habits) and subjective well-being (attitude towards life). Moreover, haematological parameters collected in the 90+ sibpairs as optional parameters by the Bologna and Rome recruiting units were used for a more comprehensive evaluation of the results obtained using the above mentioned phenotypic characteristics reported in the GEHA questionnaire. 3. to assess 90+ Italian siblings as far as their health/functional status is concerned on the basis of three classification methods proposed in previous studies on centenarians, which are based on: • actual functional capabilities (ADL, SMMSE, visual and hearing abilities) (Gondo et al., J Gerontol. 61A (3): 305-310, 2006); • actual functional capabilities and morbidity (ADL, ability to walk, SMMSE, presence of cancer, ictus, renal failure, anaemia, and liver diseases) (Franceschi et al., Aging Clin Exp Res, 12:77-84, 2000); • retrospectively collected data about past history of morbidity and age of disease onset (hypertension, heart disease, diabetes, stroke, cancer, osteopororis, neurological diseases, chronic obstructive pulmonary disease and ocular diseases) (Evert et al., J Gerontol A Biol Sci Med Sci. 58A (3): 232-237, 2003). Firstly these available models to define the health status of long-living subjects were applied to the sample and, since the classifications by Gondo and Franceschi are both based on the present functional status, they were compared in order to better recognize the healthy aging phenotype and to identify the best group of 90+ subjects out of the entire studied population. 4. to investigate the concordance of health and functional status among 90+ siblings in order to divide sibpairs in three categories: the best (both sibs are in good shape), the worst (both sibs are in bad shape) and an intermediate group (one sib is in good shape and the other is in bad shape). Moreover, the evaluation wanted to discover which variables are concordant among siblings; thus, concordant variables could be considered as familiar variables (determined by the environment or by genetics). 5. to perform a survival analysis by using mortality data at 1st January 2009 from the follow-up as the main outcome and selected functional and clinical parameters as explanatory variables. Methods A total of 765 90+ Italian subjects recruited by UNIBO (549 90+ siblings, belonging to 258 families) and ISS (216 90+ siblings, belonging to 106 families) recruiting units are included in the analysis. Each subject was interviewed according to a standardized questionnaire, comprising extensively utilized questions that have been validated in previous European studies on elderly subjects and covering demographic information, life style, living conditions, cognitive status (SMMSE), mood, health status and anthropometric measurements. Moreover, subjects were asked to perform some physical tests (Hand Grip Strength test and Chair Standing test) and a sample of about 24 mL of blood was collected and then processed according to a common protocol for the preparation and storage of DNA aliquots. Results From the analysis the main findings are the following: - a standardized protocol to assess cognitive status, physical performances and health status of European nonagenarian subjects was set up, in respect to ethical requirements, and it is available as a reference for other studies in this field; - GEHA families are enriched in long-living members and extreme survival, and represent an appropriate model for the identification of genes involved in healthy aging and longevity; - two simplified sets of criteria to classify 90+ sibling according to their health status were proposed, as operational tools for distinguishing healthy from non healthy subjects; - cognitive and functional parameters have a major role in categorizing 90+ siblings for the health status; - parameters such as education and good physical abilities (500 metres walking ability, going up and down the stairs ability, high scores at hand grip and chair stand tests) are associated with a good health status (defined as “cognitive unimpairment and absence of disability”); - male nonagenarians show a more homogeneous phenotype than females, and, though far fewer in number, tend to be healthier than females; - in males the good health status is not protective for survival, confirming the male-female health survival paradox; - survival after age 90 was dependent mainly on intact cognitive status and absence of functional disabilities; - haemoglobin and creatinine levels are both associated with longevity; - the most concordant items among 90+ siblings are related to the functional status, indicating that they contain a familiar component. It is still to be investigated at what level this familiar component is determined by genetics or by environment or by the interaction between genetics, environment and chance (and at what level). Conclusions In conclusion, we could state that this study, in accordance with the main objectives of the whole GEHA project, represents one of the first attempt to identify the biological and non biological determinants of successful/unsuccessful aging and longevity. Here, the analysis was performed on 90+ siblings recruited in Northern and Central Italy and it could be used as a reference for others studies in this field on Italian population. Moreover, it contributed to the definition of “successful” and “unsuccessful” aging and categorising a very large cohort of our most elderly subjects into “successful” and “unsuccessful” groups provided an unrivalled opportunity to detect some of the basic genetic/molecular mechanisms which underpin good health as opposed to chronic disability. Discoveries in the topic of the biological determinants of healthy aging represent a real possibility to identify new markers to be utilized for the identification of subgroups of old European citizens having a higher risk to develop age-related diseases and disabilities and to direct major preventive medicine strategies for the new epidemic of chronic disease in the 21st century.

Sviluppo, Basi Neurali e Patologie del Sé corporeo

Il presente elaborato ha per oggetto la tematica del Sé, in particolar modo il Sé corporeo. Il primo capitolo illustrerà la cornice teorica degli studi sul riconoscimento del Sé corporeo, affrontando come avviene l’elaborazione del proprio corpo e del proprio volto rispetto alle parti corporee delle altre persone. Il secondo capitolo descriverà uno studio su soggetti sani che indaga l’eccitabilità della corteccia motoria nei processi di riconoscimento sé/altro. I risultati mostrano un incremento dell’eccitabilità corticospinale dell’emisfero destro in seguito alla presentazione di stimoli propri (mano e cellulare), a 600 e 900 ms dopo la presentazione dello stimolo, fornendo informazioni sulla specializzazione emisferica substrati neurali e sulla temporalità dei processi che sottendono all’elaborazione del sé. Il terzo capitolo indagherà il contributo del movimento nel riconoscimento del Sé corporeo in soggetti sani ed in pazienti con lesione cerebrale destra. Le evidenze mostrano come i pazienti, che avevano perso la facilitazione nell’elaborare le parti del proprio corpo statiche, presentano tale facilitazione in seguito alla presentazione di parti del proprio corpo in movimento. Il quarto capitolo si occuperà dello sviluppo del sé corporeo in bambini con sviluppo atipico, affetti da autismo, con riferimento al riconoscimento di posture emotive proprie ed altrui. Questo studio mostra come alcuni processi legati al sé possono essere preservati anche in bambini affetti da autismo. Inoltre i dati mostrano che il riconoscimento del sé corporeo è modulato dalle emozioni espresse dalle posture corporee sia in bambini con sviluppo tipico che in bambini affetti da autismo. Il quinto capitolo sarà dedicato al ruolo dei gesti nel riconoscimento del corpo proprio ed altrui. I dati di questo studio evidenziano come il contenuto comunicativo dei gesti possa facilitare l’elaborazione di parti del corpo altrui. Nella discussione generale i risultati dei diversi studi verranno considerati all’interno della loro cornice teorica.

Mobi - kids - rischio di tumori cerebrali ed esposizione a campi a radiofrequenza nei bambini e negli adolescenti

Introduzione. Il rapido e globale incremento dell’utilizzo dei telefoni cellulari da parte degli adolescenti e dei bambini ha generato un considerevole interesse circa i possibili effetti sulla salute dell’esposizione a campi elettromagnetici a radiofrequenza. Perciò è stato avviato lo studio internazionale caso-controllo Mobi-kids, all’interno del quale si colloca quello italiano condotto in 4 Regioni (Piemonte, Lombardia, Toscana, Emilia-Romagna). Obiettivi. Lo studio ha come obiettivo quello di valutare la stima del rischio degli effetti potenzialmente avversi di queste esposizioni sul sistema nervoso centrale nei bambini e negli adolescenti. Materiali e Metodi. La popolazione include tutte le persone di età compresa tra 10 e 24 anni residenti nelle 4 Regioni, con una diagnosi confermata di neoplasia cerebrale primitiva, diagnosticata durante il periodo di studio (3 anni). Sono stati selezionati due controlli - ospedalizzati per appendicite acuta - per ciascun caso. I controlli sono stati appaiati individualmente a ciascun caso per età, sesso e residenza del caso. Risultati. In Italia sono stati intervistati a Giugno 2014, 106 casi e 191 controlli. In Emilia-Romagna i casi reclutati sono stati fino ad ora 21 e i controlli 20, con una rispondenza del’81% e dell’65% rispettivamente. Dei 41 soggetti totali, il 61% era di sesso maschile con un’età media generale pari a 16,5 (±4,5) anni. Inoltre il 44% degli intervistati proveniva dalla classe di età più giovane (10-14). In merito allo stato di appaiamento, nella nostra Regione sono state effettuate 7 triplette (33%) - 1 caso e 2 controlli - e 6 doppiette (29%) - 1 caso ed 1 controllo. Conclusioni. Nonostante le varie difficoltà affrontate data la natura del progetto, l’esperienza maturata fin ad ora ha comunque portato alla fattibilità dello studio e porterà probabilmente a risultati che contribuiranno alla comprensione dei potenziali rischi di neoplasie cerebrali associati all'uso di telefoni cellulari tra i giovani.