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Ottimizzazione della logistica in ambito sanitario attraverso l'uso di sistemi RFID
Get PDFThis thesis is framed in a project which aims to study innovative RFID-based management systems, to optimize logistics in a Italian Blood Transfusion Center.
Methodology envisage the analysis of processes by using several analytical tools: reports, flow charts, activity forms, Idef0 language. A Clinical Risk analysis was carried out, in order to highlight criticalities related to efficiency and effectiveness (patient safety), and to quantitatively classify them. Particularly FMECA and CREA methods were adopted. The analysis was followed by a RFID-based process re-engineering. This step, which aimed at minimize the critical issues impact, led to the drafting of a innovative design models. Key performances Indicators (KPI) were then designed and calculated for the studied models, in order to make comparisons between them and to validate them.
This methodology was adopted in two main steps, the first one in 2010 and the second one in 2013. In this thesis 2010 and 2013 analysis and synthesis are both described and compared, focusing on the 2013 project model.
The thesis describes also experimental tests of UHF RFID systems, which are not considered as the standard RFID system in blood transfusion applications.
The thesis also treats a critical feature of Sardinia Blood Transfusion Service: the optimization of logistic processes in the AOB Blood Transfusion Centre sub department which is dedicated to blood assignment for thalassemia patient
Valutazione degli aggiustamenti cardiocircolatori durante apnea statica e dinamica in apneisti d'elitè mediante l'uso di un dispositivo portatile
Get PDFAim: Considering that sympathetic activation is induced by exercise, it is reasonable to assume that hemodynamic adjustments to exercise act in opposition to those elicited by the diving response. However, cardiovascular measurements have never been performed during underwater dynamic apnoea (DA), and this hypothesis remains speculative.
Methods: Data concerning heart rate (HR), stroke volume (SV) and cardiac output (CO) during static apnoea (SA) and DA were collected from 12 elite divers by means of an impedance cardiograph adapted to the underwater environment. Mean arterial pressure (MBP), systemic vascular resistance (SVR) and arterial oxygen saturation (SaO2) were also assessed.
Five trials were performed by the divers: head-out immersion during normal breathing (test A); 3 min of SA immersed at the surface (B) and at 3 m depth (C); DA till exhaustion immersed at the surface (D) and at 3 m depth (E).
Results: Both B and C conditions led to bradycardia (_17%) compared to A and also induced a decrement in SV (_8%) and in CO (_25%), while MBP was maintained because of an increase in SVR. A significant MBP increment (+11%) was detected only during tests D and E, when a SaO2
drop was also present, whereas HR, SV and CO remained unchanged.
Conclusion: We concluded that typical diving response was present only during SA, while sympathetic activation was induced by exercise during DA, which partially obscured the effects of the diving response
Applicazioni innovative dell’ingegneria biomedica
Get PDFThe recent important advances in engineering and medicine at the molecular, cellular, and tissue
levels together with the significant modifications in people life style, the rapid aging, and the
improved life quality expectations for the world population make urgent for the scientific
committee to learn more about human body functions at a macro-, micro-, and nano-scale. In this
context, Biomedical Engineering has emerged: it uses methods and techniques proper of the
engineer field to describe, understand, and solve medical and biological issues and it allows the
cooperation among engineers, bio-physicists, physicians, and biologists.
Tissue engineering is one of the main branches of Biomedical Engineering and it has sprout to
satisfy the need of designing and building living biological tissues in vitro. This is for sure a
promising alternative to transplantation, especially to autologous transplantation. This strategy of
growing and using autologous tissues as grafts possibly makes available tissues/organs
immunologically compatible with the recipient, thus avoiding immunosuppressive therapies and
partially solving the constant shortage of donor tissues and organs. Among recent strategies to
obtain tissues in vitro, decellularization has developed. This method aims at producing acellular
biological matrices to be used as scaffolds for new organs suitable for transplantation. The first part
of PhD has dealt with the optimization of a decellularization protocol for ovine carotids, designed to
obtain an adequate biological matrix for small vascular graft.
Besides, progresses and growth of Biomedical Engineering imply the rapid spreading of innovative
materials. As a consequence, in order to guarantee the appropriate protection of human health and
of the environment, it is essential to foresee eventual adverse effects of the exposure to such new
materials, and evaluate their potential risk, both with toxicological analyses and preclinical and
clinical studies. In particular, this is a crucial issue within one of the most recent fields of
Biomedical Engineering, i.e. nanotechnologies, which are still lacking a specific regulation.
This is the reason why the second part of PhD thesis is focused on the development of a new acute
oral toxicological test in vitro, based on the use of human mesenchymal stem cells (hMSCs) and
designed according to ICCVAM guidelines. These were drafted during the validation process of the
two in vitro tests which are now approved and used, despite their limits, to evaluate acute oral
toxicology and to predict the starting dose for acute toxicity tests in vivo (ICCVAM, 2006).
Considering the promising results obtained, the hMSC test was adopted to estimate nanoparticle
cytotoxicity
Haratin di Mauritania: da status ascritto a rivendicazione identitaria. La schiavitù in prospettiva postcoloniale
Get PDFThe dissertation analyses the construction of the community of the Haratines of Mauritania, ethnic
group of former slaves and their descendants, of black origins and Arabised over time. Despite
abolition of slavery, 10-15% of the Haratines are still considered in dependence on their former
masters, especially in rural areas. The study highlights the transformation of what to be “Haratines”
meant over time and what concurred to transform a social status into an ethnic group, whose
members are actually affirming their autonomous identity from the beydane society, in which they
were usually included in the past.
Until independence (1960) the term Haratines (sing. Hartani) was only referred to freed
slaves and their descendants, whereas slaves were called ‘abid (sing. ‘abd), then constituting the
two lower social status of the Arab-Berber (beydane) society of Mauritania. Even if French
colonisation didn‟t deeply change their condition, some antislavery policies were applied at the
beginning of the territorial expansion. From late 1880s, especially in northern Senegal and Mali, the
French tried to carry out an antislavery action by creating some „freedom villages‟ where runaway
slaves could find a place to live and work freely, receiving „freedom licenses‟. Moreover, treats
with local chiefs established the transformation of slavery into temporary forced labour, freeing
slaves ten years later. The expansion in the North of the Senegal River Valley and the need to
administrate a vast desert area, populated by few nomadic people, forced France to substantially
maintain traditional leaderships and the Arab social organization. Indeed, echoes of emancipation
and some wage labour (boys, interpreters, guides, cooks, etc.) reached slaves and Haratines.
Moreover, a few Haratines attended French schools in the villages. These men founded the El-Hor
antislavery movement in 1974, which later fought against slavery, thus obtaining its abolition in
1981, even if it was just a formal one. The term ‘abid (sing. ‘abd) went out of use, and „Haratines‟
was extended to people still in dependence, too. Desertification and urbanization concurred to free
some slaves, who moved in the ghettos of Nouakchott where they began to be aware of their
exploitation and of their different identity from Arab-Berber masters. From 2008, a new impulse to
antislavery fight came from IRA Mauritanie, which leader Biram Ould Dah Ould Abeid innovated
and radicalised the protest. Moreover, IRA Mauritanie affirms that the Haratine community is
different from the Arab one and that the Haratines have an autonomous identity, which is
characterised by race (“Haratines are black”) and their own Haratine culture
Persuasive Mobile Systems Design to Help People be Physically Active
Get PDFThis PhD thesis puts forward the results of research activities I have carried out at
the Department of Mathematics and Computer Science of the University of Cagliari since
March 2011. My work can be placed in the general field of Human-Computer Interaction and, more
precisely, in the relative new and trending area of Persuasive Computing. Broadly speaking, a
persuasive system is a system designed to change some habits or behaviors of the users by means
of persuasion.
My research activity sets out to address fundamental questions related to the application of
mobile persuasive technologies to real-life problems, including: Are mobile technologies able to
persuade people to a more physically active lifestyle? Are currently available systems actually
effective? How can user experience design be improved in this class of softwares? How can human
to device interaction be improved to favor users during their physical activities? Are these systems
really effective over long time periods?
The research activity this thesis presents, aimed at answering at previous questions through
the study of the effects of mobile persuasive systems designed to foster people to a more active
lifestyle.
In literature, we can find many examples of prototypal persuasive mobile system. The results
they reported are encouraging but, almost always, they are deducted from qualitative studies
over short periods of time.
This work endeavors to overcome these limitations through the development of a real world
complex software platform designed to encourage people to a more active lifestyle. Users interact
with the platform mainly through two Android-based applications freely available on the market.
Thanks to our platform, our experimentations can rely on a conspicuous base of real users and
a huge amount of automatically recorded statistics for potentially unlimited periods of time
Utilizzo di nuove tecniche di campionamento passivo di contaminanti prioritari nelle acque marino-costiere della Sardegna (Mediterraneo centro-occidentale)
Get PDFIn the coastal and marine environment a growing number of contaminants are considered
dangerous for their ability to damage ecosystems and move along the food chains.
The assessment of such pollution, which includes among other polycyclic aromatic
hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals, is complex and
subject to numerous criticisms and suggestions for improvement.
The methodology for assessing the quality of surface water is based on water withdrawals
on time to entrust the chemical analysis. Many of priority contaminants listed in the Directive
"Marine Strategy" 2008/56/EC are however micropollutants present in very low concentrations,
often below the detection limit of the methods currently available. Where the concentration of
these pollutants exceeds the limits of the law, as in the sediments, it may not be dangerous
because this is not bioavailable forms.
In this study were tested for marine waters passive sampling techniques.
Aqueous concentrations of individual PAHs and PCBs were determined in two coastal sites
of marine protected areas (MPAs): Asinara and the La Maddalena Archipelago, Sardinia
(Western Mediterranean Sea). The use of semi-permeable membrane devices (SPMDs) enabled
the detection of dissolved PAHs and PCBs, even at very low concentrations of (pg L-1, ng L-1) in
seawater.
The results reveal differences between the two sampling areas related to the concentration of
the individual PAHs, which provide information concerning the pollution sources affecting
relatively pristine environments.
The PCBs were Generally Observed at levels below the detection limits of the method
utilized.
The concentration of aqueous metal ions cadmium, lead, mercury, nickel, chromium and
copper have been investigated in the Santa Gillalagoon (South Sardinia). The use of Diffusive
Gradients in Thin Films (DGTs) showed that the concentrations of bioavailable fraction (ngL-1)
of all metals monitored were below legal limits. However, the results revealed differences in the
concentration of individual metals and provided information concerning the sources of pollution.
The passive samplers were useful tools for the assessment of the EQSs and the prevention of
pollution in sea water
Tra Sardegna e Catalogna. Artisti e committenti nella prima età moderna alla luce delle fonti documentali
Get PDFThis research aims to investigate the relationship between artists and patrons and the dynamics of
production, circulation, use of paintings in reference to Sardinia in the late fifteenth-early sixteenth
century in its relations with Catalonia. The primary objective is to search out new data on episodes
and steps considered fundamental in the art, the knowledge of which is limited by the lack of
documentation and the small number of surviving works; complementary objective is to try to
understand what was the nature of the artist-client relationship and how the mechanisms of
production of the works and their circulation were configured and according to which patterns were
transposed by the users. To go back to the circumstances that led to the creation of the art work is
necessary to refer to a set of data that go beyond the canonical commission contracts of works. Any
news about the actions, the movements and contacts of the patrons, the artistic operators, suppliers
of raw materials (and therefore of producers and merchants) was (re)read and (re)analyzed to
identify new elements that could expand the limited knowledge in our possession
Sintesi di molecole organiche enantiomericamente arricchite con l'uso della catalisi organica
Get PDFThe main topic of this thesis is the use of organocatalysis to synthesize organic compounds enantiomerically enriched.
The first matter is about the synthesis of α-amino thioester derivatives through a tandem condensation-intramolecular rearrangement-protonation, this is a conceptually novel chiral Brønsted base/ Brønsted acid catalytic method that provides a number of important synthetic building blocks in good yields and with moderate and good enantioselectivities.
The second topic is concerned to the synthesis of aldols derivatives of pyridine carbaldehydes functionalized in different positions using simple amino acids derivatives as catalysts, for example L-proline, L-pyrrolidine tetrazole and so on. This is important because is necessary to found news synthetic methods to produce pyridines nucleus that are very important building block for drugs.
Following it is illustrated a preliminary result of a new methodological approach to the synthesis of enantiomerically enriched cyclopentanones starting from cyclobutanones and spirocyclopentanones, it is possible to expand the ring through an organocatalysed Michael reaction. This new approach takes advantages of the introduction of the α,β-unsatured aldehyde function on cyclobutanones.
Finally, supramolecular interactions by halogen bonding are described. These occurs between enatiomerically enriched aldols benzothiophene derivatives, synthesized by means of organocatalysed reactions. These kinds of interactions are strongly important in supramolecular chemistry but also in biochemistry, materials and crystal engineering
Preneoplastic hepatocyte hypothyroidism underlies hepatocellular carcinoma progression
Get PDFThyroid hormones elicit many cellular and metabolic effects. Most of them are mediated by the thyroid hormone 3,5,3’-L-triiodothyronine (T3) nuclear receptors (THRs), which act as transcription factors. THRs have also been implicated in tumorigenesis, although it is unclear whether they act as oncogenes or tumor suppressors. Here, experiments were performed to determine the role of THRs in hepatocellular carcinoma development. Using the Resistant-Hepatocyte model (RH model) of rat hepatocarcinigenesis, we found downregulation of THRβ1 and THRα1 in most of early preneoplastic lesions and of HCCs. THRβ1 and, to a lesser extent, THRα1 downregulation was observed only in preneoplastic lesions positive for the progenitor cell marker cytokeratin-19 (KRT-19), which are characterized by a higher proliferative activity compared to KRT-19 negative ones. Accordingly, THRs target genes were strongly down-regulated in KRT-19+ lesions. In rat HCC THRβ1 decrease was not due to hypermethylation of the THRβ1 promoter but was associated with an increased expression of miR-27a, -181a and -204, known to target this receptor in other cell types. Accordingly, transfection of hepatoma cell lines with these miRNAs led to down-regulation of THRβ1. Downregulation of THRβ1 expression was observed also in the vast majority of the analyzed human HCCs compared to peritumorous liver of the same patients or to normal liver. These results show that downregulation of THRs, especially THRβ1, is an early and relevant event in liver cancer development, species- and etiology-independent. They also suggest that a hypothyroid status of preneoplastic lesions may contribute to their progression to HCC
Essays on choice modeling
Get PDFThe increased interest in modeling preference heterogeneity in Choice Experiments (CE) data has promoted the use of choice models within the family of Logit Mixture models. However, researchers have scarce guidance on how to select the appropriate model. A Monte Carlo study is set up to analyze the performance of different information criteria and tests used to discriminate between models, either nested or non-nested. In particular, within non-nested models, four criteria and three tests are assessed, all of them based on the Kullback-Leibler Information Criterion (KLIC): the AIC, AIC3, CAIC and BIC information criteria, and the tests for non-nested models proposed by Vuong, Horowitz and Ben-Akiva and Swait. Our results indicate that some criteria (especially CAIC) work better than others; and that, when feasible, information criteria should be complemented by the Vuong test, which has a low power, but it virtually never selects the wrong model, while both the Horowitz and the Ben-Akiva and Swait tests too often provide wrong indications. The paper concludes with a CE application dealing with public acceptance of wind farms, where the indications drawn from the Monte Carlo analysis are used to inform model selection