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Algorithms and systems for home telemonitoring in biomedical applications
Get PDFDuring the past decades, the interest of the healthcare community shifted from the simple treatment of the diseases towards the prevention and maintenance of a healthy lifestyle. This approach is associated to a reduced cost for the Health Systems, having to face the constantly increased expenditures due to the reduced mortality for chronical diseases and to the progressive population ageing. Nevertheless, the high costs related to hospitalization of patients for monitoring procedures that could be better performed at home hamper the full implementation of this approach in a traditional way. Information and Communication Technology can provide a solution to implement a care model closer to the patient, crossing the physical boundaries of the hospitals and thus allowing to reach also those patients that, for a geographical or social condition, could not access the health services as other luckier subjects. This is the case of telemonitoring systems, whose aim is that of providing monitoring services for some health-related parameters at a distance, by means of custom-designed electronic devices. In this thesis, the specific issues associated to two telemonitoring applications are presented, along with the proposed solutions and the achieved results.
The first telemonitoring application considered is the fetal electrocardiography. Non-invasive fetal electrocardiography is the recording of the fetal heart electrical activity using electrodes placed on the maternal abdomen. It can provide important diagnostic parameters, such as the beat-to-beat heart rate variability, whose recurring analysis would be useful in assessing and monitoring fetal health during pregnancy. Long term electrocardiographic monitoring is sustained by the absence of any collateral effects for both the mother and the fetus.
This application has been tackled from several perspectives, mainly acquisition and processing. From the acquisition viewpoint a study on different skin treatments, disposable commercial electrodes and textile electrodes has been performed with the aim of improving the signal acquisition quality, while simplifying the measurement setup. From the processing viewpoint, different algorithms have been developed to allow extracting the fetal ECG heart rate, starting from an on-line ICA algorithm or exploiting a subtractive approach to work on recordings acquired with a reduced number of electrodes. The latter, took part to the international "Physionet/Computing in Cardiology Challenge" in 2013 entering into the top ten best-performing open-source algorithms. The improved version of this algorithm is also presented, which would mark the 5th and 4th position in the final ranking related to the fetal heart rate and fetal RR interval measurements performance, reserved to the open-source challenge entries, taking into account both official and unofficial entrants. The research in this field has been carried out in collaboration with the Pediatric Cardiology Unit of the Hospital G. Brotzu in Cagliari, for the acquisition of non-invasive fetal ECG signals from pregnant voluntary patients.
The second telemonitoring application considered is the telerehabilitation of the hand. The execution of rehabilitation exercises has been proven to be effective in recovering hand functionality in a wide variety of invalidating diseases, but the lack of standardization and continuous medical control cause the patients neglecting this therapeutic procedures. Telemonitoring the rehabilitation sessions would allow the physician to closely follow the patients' progresses and compliance to the prescribed adapted exercises.
This application leads to the development of a sensorized telerehabilitation system for the execution and objective monitoring of therapeutic exercises at the patients' home and of the telemedicine infrastructure that give the physician the opportunity to monitor patients' progresses through parameters summarizing the patients' performance. The proposed non-CE marked medical device, patent pending, underwent a
clinical trial, reviewed and approved by the Italian Public Health Department, involving 20 patients with Rheumatoid Arthritis and 20 with Systemic Sclerosis randomly assigned to the experimental or the control arm, enrolled for 12 weeks in a home rehabilitation program. The trial, carried out with the collaboration of the Rheumatology Department of the Policlinico Universitario of Cagliari, revealed promising results in terms of hand functionality recovering, highlighting greater improvements for the patients enrolled in the experimental arm, that use the proposed telerehabilitation system, with respect to those of the control arm, which perform similar rehabilitation exercises using common objects
Empirical faithfulness and typicality: a pragmatic reading of Everett's pure wave mechanics
Get PDFEverett’s Relative State Formulation is one of the most famous and debated interpretations of Quantum Theory. Further deepening of the debates has been made possible by the discovery of his unpublished notes and manuscripts.
My purpose is to examine Everett’s ideas about physical theories, and show that his understanding of actual experience can be put into correspondence with the latest forms of constructive empiricism and empirical adequacy: the problem of ‘extra structure’, which is the reason for metaphysical interpretations, can be solved by using a pragmatic criterion to choose in which way the theory should correspond to empirical evidence.
A quantitative justification for probabilities in Everettian context is given in terms of typicality
Caratterizzazione cardio metabolica di atleti in età evolutiva e confronto tra èlite e non èlite
Get PDFThe aim of this study was to compare the cardio metabolic responses in young athletes highlighting any differences between the categories elite and non-elite. Furthermore, we wanted to create a database of references for these categories of athletes, given the very poor and outdated present literature.
68 subjects were involved in this protocol (47 males and 21 females) whose mean ± standard deviation (SD) age, height, weight and BMI were respectively of 16 ± 0.8 years of age; 174 ± 8.8 cm; 63 ± 10.2 kg; 21 ± 2.4. The athletes were divided into two groups: the first (36 individuals) were part of the elite athletes, those enrolled in professional young teams; the second is made up of non-elite athletes (32 individuals).
The protocol included the performance of two tests to be performed on different days. The first to be performed was an incremental test (CPX) on the treadmill. Then after an average delay of a day, an all-out (AOT)test was carried out for the determination of the anaerobic component. The breathing pattern was measured using a portable metabolimeter (VO2000, Med Graphics, USA), and the values were analyzed for mean ± standard deviation. A t-test for unpaired data was used to find statistically significant differences between the two groups
(p <0.05).
Regarding CPX, statistical analysis showed a difference only in the speed reached at maximum effort, with the other parameters being almost identical. Moreover, the all-out test showed this difference in both the maximum speed and the time of all-out.
In light of the observations can be said that for subjects in childhood the number of hours per week of training, and the sport, do not affect significantly the development of physiological characteristics: the difference between elite and not could be found in the technical capabilities of the athlete
Essays on early adulthood dynamics
Get PDFTransition into the labour market is a crucial moment for young adults, as it yields a number of
choices that may affect their lives not only in the short-term but also in the medium- and long-run.
Here, I focus on two key aspects. First, I investigate residential location choices in the first years
after leaving full-time education and evaluate the relative importance of individual, family and
regional characteristics that lead young adults to move away from the place of origin. Second, I
evaluate the impact of experiencing job instability during the first years of the individuals' careers
on fertility decisions in the short-run. In both cases, I deal with endogeneity issues and find that
individual observable and unobservable characteristics are the main factors that drive these choices
in early adulthood
Development and characterisation of Monolithic Active Pixel Sensor prototypes for the upgrade of the ALICE Inner Tracking System
Get PDFALICE (A Large Ion Collider Experiment) is dedicated to the study and characterisation of the Quark-‐Gluon Plasma (QGP), exploiting the unique potential of ultrarelativistic heavy-‐ion collisions at the CERN Large Hadron Collider (LHC). The increase of the LHC luminosity leading up to about 50 kHz Pb-‐Pb interaction rate after the second long shutdown (in 2018-‐2019) will offer the possibility to perform high precision measurements of rare probes over a wide range of momenta. These measurements are statistically limited or not even possible with the present experimental set up. For this reason, an upgrade strategy for several ALICE detectors is being pursued. In particular, it is foreseen to replace the Inner Tracking System (ITS) by a new detector which will significantly improve the tracking and vertexing capabilities of ALICE in the upgrade scenario. The new ITS will have a barrel geometry consisting of seven layers of Monolithic Active Pixel Sensors (MAPS) with high granularity, which will fulfil the material budget, readout and radiation hardness requirements for the upgrade. Intensive R&D has been carried out in the last four years on MAPS in the framework of the ALICE ITS upgrade. Various small scale sensors have been designed in the TowerJazz 0.18 um imaging sensor technology to study noise, charge collection efficiency and signal-‐to-‐noise ratio. This work presents the main characterization results obtained from the measurements performed on two small scale prototypes (MIMOSA-‐32 and MIMOSA-‐32ter) with X-‐ray sources and beams of particles. The architecture of an innovative full scale MAPS prototype (Alice Pixel Detector, ALPIDE) is also presented that is based on an AC-‐sensitive front end and on a hit-‐ driven readout. The first results on the ALPIDE prototype showed that the sensor is fully functional and that it provides performance in terms of readout time, power density and noise much better than the state of the art MAPS based on the rolling shutter readout, which makes this type of sensors very attractive for employment in the new ALICE ITS
Vera o falsa riga dantesca del pensiero poetico leopardiano verso il termine dello Zibaldone
Get PDFIn one of the last pages of his Zibaldone, Leopardi cites the famous passage from Purgatorio XXIV,
where Dante defines his poetry as the activity of a penman to whom Love dictates. While assumed
as a cornerstone of Leopardi's conception of poetry, the Dantean apophthegm – «I' mi son un che
quando Amor mi spira noto» (One am I, who, whenever Love doth inspire me, note) – is
deliberately and significantly altered, as the quotation states: «I' mi son un che quando Natura parla
ec.» (One am I, who, whenever Nature speaks etc.). The dissertation aims to grasp the most of the
critical and hermeneutical fecondity of this passage, quite noteworthy notwithstanding its shortness
and apparently fortuitousness, and above all its ‘strange’ ambiguity.
In order to decipher Leopardi's altered quotation, the investigation researches the complex array of
relationships linking his aestetic with some of the most relevant aspects of his vast philosophical
speculation: the poetic and ethical concept of naturality; the cognitive and antropological process of
the habit; the importance of human imagination and of human disposition to the lyrical expression
of himself; the leading, if ambivalent, ethical principle of ‘amor proprio’ (self-love) and its
connections with Leopardi's original re-thinking of poetic sublime.
Following the path of innovation and continuity, change and repetition, difference and analogy,
which is implicitly traced by the intertestual device of the modified quotation, the thesis establishes
a comparison between Leopardi's speculative achievements concerning the idea of poetry and
Dante's analogues. As a result, the quotation appears to throw up a bridge across centuries of
speculative thinking about poetry, affirming the universal value of a conception of poetry hinged on
the essential elements of the lyric expression of the self, of human imagination structuring
individual creativity and of the sublime leap guiding and animating it
Il giornalismo in Sardegna dall'istituzione della Regione Autonoma ai giorni nostri. Tra conservazione e innovazione
Get PDFThe aim of this work is to carry out a study on the history of journalism in Sardinia from the institution of the Autonomous Region in 1948 to present days. This study will put into relief the features that characterized the regional media system, investigating its evolution over the decades. This was an important period for the region, which in the Sixties would have focused on the modernization of its economy, moving from a predominantly agricultural to an industrial structure. The main actor of the industrialization process would have been a class of entrepreneurs coming from Northern Italy. The process of economic modernization has also had reverberations in the information sector, due to the emergence of a monopoly of the petrochemical industry on the editorial property of the two regional newspapers "L'Unione Sarda" and "La Nuova Sardegna".
This thesis intends to use a combination of sources (from newspapers to financial statements, from the oral testimony to the archival sources) that may allow to relate the history of journalism with the economic and financial affairs of the leading Sardinian media. Not only will this work try to describe the internal story of the regional media, making a list of theirs directors, their editorial composition and their editorial line, but also its goal is to understand – without having any claim to completeness – how these media have described Sardinia in the last sixty-five years. Hence, it will try to give an answer to the following questions: what did Sardinian newspapers write about? And what were the main themes they dealt with? How did they face the events and problems emerged after the Second World War?
The research will focus not only on how Sardinia was described by the local media, but also on how this region was described by national newspapers and magazines. In this study Sardinia is seen from two main points of view: "Sardinia seen from the inside" and "Sardinia seen from the outside". The analysis of Sardinian media will move from newspapers to magazines, from radio to television and to websites.
This work, although it is proposed to trace the history of journalism in a specific region, will try, as far as possible, to place the local events within the national dynamics. The hypothesis of this study is that Sardinia, despite its geographical isolation, has not been a peripheral reality in the field of journalism. It would prove to be often the protagonist, fulfilling a central role, sometimes as a pioneer and forerunner of trends that occurred later on a national scale.
As it will be demonstrated in the present study, the region was indeed a cutting edge, particularly in the emergence of private radios and televisions, in the convergence of various media,
in the Internet field, in free press and digital terrestrial television. Sardinia can be regarded almost as a breeding ground for many experiments, a sort of local observatory for technological innovations to be exported on a large scale
L'architettura del moderno in Sardegna. Il caso di Arborea. Analisi delle tecniche costruttive e interventi per il recupero
Get PDFThis research concerns the analysis of a case study, the city of Arborea
in Sardinia, from the specific perspective of technologies and construction
tecnhiques used at the time of the establishment of the settlement, which
took place between the ‘20s and ‘30s of the twentieth century, as a result
of an extensive reclamation of a portion of Terralba’s Campidano conducted
by Società Bonifiche Sarde. The town, already known under the name
of Mussolinia di Sardegna, was born as a services centre for people who
used to live in that territory - people were mostly placed in farm-houses or in
productive centres of the company - and plays a role of a great importance.
The foundation of the settlement represents a sort of snapshot of the level
of the Sardinia’s technological development during the 30’s and, most of all,
it’s very important from the construction history’s point of view, because it
provides informations that make up a progress tile, if compared to the actual
level ok knowledge, about how technological modernization took place in a
transition era from traditional technologies to modern ones, that are mostly
represented by the introduction of reinforced concrete.
This work has been developed starting from some reflections about restoration
of modern architecture and from the role that construction history and
the knowledge of material aspects of the XX century’s architecture play in this
field of study; it has been carried on mostly by means of archival research on
original and fresh documents, and supported by field surveys.
Collected information, so specific because of their intimate relationship with
the context, has been compared to the Sardinian and Italian technological
context of the first decades of the XX century; thus, this work provides tools
for the comprehension of the level of novelty that Arborea’s establishment
represents.
As a result, this research is the first step as well as a knowledge base, for further
surveys and studies directed not only to a more in-depth analysis of technological
aspects but also to define, in the future, tools functional to recovery
and restoration intervetions on this architectural heritage, so important and
so representative of a period characterized by great changes, in Sardinia
Non-volatile organic memory devices: from design to applications
Get PDFThe research activity described in the attached dissertation focused on the development, fabrication and characterization of new non-volatile memory elements based on organic technology. During the last few decades, organic materials based devices have attracted considerable interest due to their great potential for future electronic systems. Low fabrication costs, high mechanical flexibility and versatility of the chemical structure, good scalability and easy processing are the unique advantages of organic electronics. As memory devices are essential elements of any kind of electronic system, the development of organic memory devices is fundamental in order to extend the application of organic materials to different electronic circuits. Research on organic electronic memories is currently at a rapid growth stage, since it is recognized that they may be an alternative or supplementary to the conventional memory technologies. Despite considerable progress in the advancement of novel memory technologies in recent years, some challenging tasks still need to be resolved.
The Ph.D. research activity of this thesis is related to the still -opened challenges in the organic memories technologies. In particular, it focused mainly on the study, development, fabrication and characterization of new non-volatile organic memory elements based on resistive switching. The activity has been carried out in the frame of the European project “HYbrid organic/inorganic Memory Elements for integration of electronic and photonic Circuitry” (HYMEC), which involved the University of Cagliari during the last three years. The project goal was to realize new hybrid inorganic/organic resistive memory devices with functionality far beyond the state of the art. A complementary activity on transistor-based organic memory devices has been also carried out and described in this thesis.
As regards resistive memory devices, the research activity included design, fabrication and testing of a novel non-volatile memory device based on the combination of an air-stable organic semiconductor and metal nanoparticles. This topic required the development of technology and procedures for easy and reliable production of devices as well as the definition of measurement protocols. The proposed structure was thoroughly characterized by morphological techniques, which allowed to interpret the resistive switching mechanisms in terms of formation and rupture of metallic filaments inside the organic layer assisted by the metal NPs. The obtained performances are the best reported so far in literature, and, to our knowledge, the statistics analysis is the largest ever reported for organic-based resistive memories. The developed technology was then successfully applied on flexible plastic substrates. The definition of technological processes for the reliable fabrication of high performance printed organic memory devices was also carried out: this work clearly demonstrates the real possibility of fabricating high performance printed memory elements. A significant effort was also devoted to the development of basic memory/sensor systems entirely fabricated on plastic substrates. The suitability of organic non-volatile memory devices for the detection and the storage of external parameters was demonstrated. The results definitely demonstrated the feasibility of the proposed technology for the fabrication of systems including organic memories for their final application in different industrial processes, including e-textile and smart packaging.
As regards transistor memory devices, highly flexible Organic Field-Effect Transistor (OFET)-based memory elements with excellent mechanical stability and high retention time were developed. As main innovation with respect to the state of the art, low voltage operation of the OFET-based memory was investigated. Such an activity was also related to the development of reliable measurement procedure
Essays on the composition of government spending and economic growth
Get PDFThe link between fiscal policy and economic growth has raised a great deal of debate at both theoretical and empirical level. Public expenditure and national income have been the focus of public finance, since the amount of public expenditure has been increasing over time in almost all countries in the world. The aim of this study is to empirically examine the effects of different types of government expenditures on economic growth, with particular attention to the Italian case.
The first chapter of this dissertation offers a literature review on the relationship between the size of government and economic growth to show how findings follow a contrasting pattern. Moreover, the more recent strand of the literature attempts to evaluate the influence of functional breakdown of public spending on economic growth, thus going beyond the simple division between productive and unproductive expenditure. Studies that disaggregate public expenditures in healthcare, education, defence, infrastructures, housing sector and other expenditures categories show that the results change according to the specific countries under scrutiny, the analysed period and methodologies applied.
Chapter two and three examine the empirical relationship between government spending composition and economic growth within an endogenous growth framework as developed by Ghosh and Gregoriou (2008) with two public goods, one being a priori more productive than the other. In particular, the added value of the second chapter lies in its empirical analysis which is based on a panel of 19 Italian regions over the period 1996-2007. Our interest is to estimate the influence of economic and functional expenditure categories of the general government on real per capita GDP growth rate. The functional breakdown of expenditures includes six components, which have been obtained aggregating the thirty sectoral expenditure components on the basis of the available data. Interestingly, inside functional categories we distinguish between capital and current items. Using dynamic panel GMM estimators, economic and functional components seem not to have any significant effect on growth. However, the results improve when we take into account spatial correlation through a spatial lag model. Although there is no evidence of spatial autocorrelation in our specifications, the results show that the capital and current expenditure behaviour is driven by capital transfers and financial assets. In addition, it is also induced by current expenditure on personnel, purchases on goods and services, interest expense and other unclassified current expenditures. As for the functional components, the main result is given by capital expenditure on economic affairs, such as infrastructures, which plays an important role in augmenting the economic growth rate among Italian regions in the period investigated here. Current expenditure on health, and capital and current expenditure on general public services had a negative and statistically significant effect on growth.
The third chapter offers an empirical investigation of the relationship between government spending composition and economic growth by using a historical time-series (for the period 1862-2007) on the Italian case. Our aim is to estimate the effects of economic and functional components of government spending on economic growth both in the short- and long-run. After testing our series for unit roots with structural breaks, we divided the sample period into two main sub-samples and estimate the influence of the different components of public spending by means of an ARDL model. Regarding the first sample (1970-2007), the most surprising results is the negative effect of capital expenditure on economic growth, both in the short- and in the long-run. In particular, capital expenditure appears to have been excessively high during the period under scrutiny, thus resulting unproductive at margin. On the other hand, current expenditure has an insignificant effect on economic growth both in the short- and in the long-run. Among functional components, expenditures on defence and economic affairs have a statistically significant effect on economic growth in the short-run. In contrast, the latter maintains a significant or even negative effect on real per capita GDP in the long-run only. As for the second sample period (1862-1969), we split it endogenously so as to establish two structural break dates. Overall, the results vary across sub-samples, but educational spending shows a positive and statistically influence on per capita GDP in the long-run