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PARADIGMI ASSOCIATIVI DI TMS APPLICATI ALLO STUDIO DELLA RELAZIONE TRA SONNO E PLASTICITA' SINAPTICA
No full textNeural Basis of Motor Planning for Object-Oriented Actions: the Role of Kinematics and Cognitive Aspects
No full textThe project I have carried out in these three years as PhD student pursued the aim of describing the motor preparation activity related to the object oriented actions actually performed. The importance of these studies comes from the lack of literature on EEG and complex movements actually executed and not just mimed or pantomimed. Using the term ‘complex’ here we refer to actions that are oriented to an object with the intent to interact with it.
In order to provide a broader idea about the aim of the project, I have illustrated the complexity of the movements and cortical networks involved in their processing and execution. Several cortical areas concur to the plan and execution of a movement, and the contribution of these different areas changes according to the complexity, in terms of kinematics, of the action. The object-oriented action seems to be a circuit apart: besides motor structures, it also involves a temporo-parietal network that takes part to both planning and performing actions like reaching and grasping. Such findings have been pointed out starting from studies on the Mirror neuron system discovered in monkeys at the beginning of the ‘90s and subsequently extended to humans. Apart from all the speculations this discovery has opened to, many different researchers have started investigating different aspects related to reaching and grasping movements, describing different areas involved, all belonging to the posterior parietal cortex (PPC), and their connections with anterior motor cortices through different paradigms and techniques.
Most of the studies investigating movement execution and preparation are studies on monkey or fMRI studies on humans. Limits of this technique come from its low temporal resolution and the impossibility to use self-paced movement, that is, movement performed in more ecological conditions when the subject decides freely to move. On the few studies investigating motor preparation using EEG, only pantomime of action has been used, more than real interactions with objects. Because all of these factors, we decided to get through the description of the motor preparation activity for goal oriented actions pursuing two aims: in the first instance, to describe this activity for grasping and reaching actions actually performed toward a cup (a very ecological object); secondly, we wanted to verify which parameters in these kind of movements are taken into account during their planning and preparation: because of all the variables involved in grasping and reaching movements, like the position of the objects, its features, the goal of the action and its meaning, we tried to verify how these variables could affect motor preparation creating two different experiments. In the first one, subjects were requested to perform a grasping and a reaching action toward a cup and in a third condition we tied up their hands as fist in order to verify what it could happen when people are in the condition of turning an ordinary and easy action into a new one to accomplish the final task requested. In the second experiment, we better accounted for the cognitive aspects beyond the motor preparation of an action. Here, indeed, we tested a very simple action like a key press in two different conditions. In the first one the button press was not related to any kind of consequence, whereas in the second case the same action triggered a video on a screen showing a hand moving toward a cup and grasping it (giving like a video-game effect).
Both the experiments have shown results straightening the role cognitive processes have in motor planning. In particular, it seemed that the goal of the action, along with the object we are going to interact with, could create a particular response and activity starting very early in the posterior parietal cortex.
Finally, because of the actions used in these experiments, it was important testing the hypothesis that our findings could be generalized even to the observation of those same actions. As I mentioned before, object-oriented actions have received great attention starting from the discovery of the mirror neuron system which showed a correspondence between the cortical activity of the person performing the action with the one produced in the observer. Such a finding allowed to describe our brain as a social brain, able to create a mental representation of what the other person is doing which allows us to understand others gesture and intentions. What we wanted to test in this project was the possibility that such a correspondence between the observer and the actor would had been extended even to the motor preparation period of an upcoming action, giving credit to the hypothesis of considering the human brain as able to even predict others actions and intentions besides understanding them. In the last experiment I carried out in my project, thus, I used the same actions involved in the first experiment but asking this time to observe them passively instead of performing them.
The results provided in this study confirmed the cognitive, rather than motor, role the PPC plays in action planning. Indeed, even when no movements are involved, the same structure are active reflecting the activity found in the execution experiment.
The main result I have reported in this dissertation is related to the suggestion of a new model to understand the role the PPC has in object-oriented movements. Unlike previous hypothesis and models suggesting the contribution of PPC in extracting affordances from the objects or monitoring and transforming coordinates between us and the object into intention for acting, we suggest here that the role of the parietal areas is more to make a judge about the appropriate match of the action goal with the affordances provided by the object. When actually the action we are going to perform fits well with the object features, the PPC starts its activity, elaborating all those coordinates representation and monitoring the execution and programming phases of movement. This model is well supported by results from both our experiments and well combines the two previous models, but putting more emphasis on the ‘goal-object matching’ function of the PPC and the Superior parietal lobe (SPL) in particular
SALVAGE THERAPY WITH HIGH INTENSITY FOCUSED ULTRASOUND IN LOCAL RADIO RECURRENT PROSTATE CANCER
No full textIntroduction & Objectives.- To evaluate the predictive factors for local failure with follow-up- biopsy after whole-gland salvage HIFU in local radio-recurrent PCa pts and to analyses the effects adverse following the therapy in terms of morbidity and quality of life on short-term.
Materials and Methods.-From April 2006 to Sept 2010. Fifty-five pts with biopsy-proven localized radio-recurrent PCa and no distant metastasis, were subjected to whole- gland salvage HIFU using Sonablate®500. PSA levels, IPSS, IIEF-5, QoL and Adverse events (CTCAE) questionnaires were assessed at 45, 90, 180 days and 12 months respectivelly. Follow-up biopsy was done systematically at 180 days after treatment. The data was prospectively collected and retrospectively analyzed. Potential predictive factors for local recurrence were explored using forward stepwise conditional regression. For comparison between groups, the Mann-Whitney U test, χ2, and Fisher’s exact test were used where appropriate. Two-sided p values <0.05 were considered statistically significant.
Results.-47 pts (85%) had external Beam Radiation, 8(15%) brachytherapy and 17(31%) were underwent to androgen deprivation pre-HIFU treatment. Mean follow-up was 25 (5-56) months. Control biopsies were available in 49(89%) pts. Local relapse was detected in 14 (25%) pts at 180 days. Location of positive biopsy pre-HIFU was an independent predictive factor for local failure (OR:5.81;95%CI 1.65-20.46, p=0.008). The mean post-salvage PSA nadir 0.19(0.02-3.30) ng/ml with a median time of 2.25(1-5-33)months. Erectile dysfunction increased after treatment from 42% to 65% at 1 year (p=0.005). At univariable analysis, prostate volume (p=0.010), IPSS (p=0.002), showed statistical difference at 12 months compared with the basal values. No statistically differences were observed (p=0.064) in the QoL evaluation in pre-HIFU and post therapy at 1 year. Rectourethral fistula occurred in 2(3%) pts, moderate stress urinary incontinence in 2(3%), and urinary retention requiring intervention in 3(5%). 25 pts (45%) presented any AEs post-treatment. In the multivariable analysis clinical stage for T3vsT1 ( OR: 0.09; p=0.017) and Gleason score 6vs7(OR): 4.64; p=0.028) were associated with increased risk of AES. There was no difference in complications between EBRT and BT pts.
Conclusions.- Our preliminary results using HIFU showed a low rate of complications with acceptable local cancer control at short- term, being comparable to the reported literature. The lack of long-term follow-up represent the main limitation in the evaluation of feasibility of it minimally invasive treatment. A prospective FDA-sponsored multicenter controlled trial is underway to confirm its utility.N/
Bifurcations in Hamiltonian systems around symmetric resonances
No full textWe investigates the orbit structure of two degrees of freedom nonlinear Hamiltonian systems around symmetric resonances. With this we mean Hamiltonian dynamical systems close to an equilibrium, invariant with respect to reflection symmetries in both configuration variables, in addition to the time reversion symmetry, and with quadratic part with unperturbed frequencies close to a resonant ratio. Such systems are naturally apt to be treated as perturbed nonlinear oscillators. The motivation behind this work lies in the study of problems arising in Galactic Dynamics, in which reflection symmetries appear to describe the orbital structure of elliptical galaxies. The analysis is performed combining three different mathematical tools: Perturbation Theory (in particular, the Poincaré-Birkhoff normal forms), Singularity Theory and Lie
Symmetry Theory. Moreover, the very nature of the problems which motivated the study leads to consider not only standard perturbation and normal forms theory, but also the Verhulst’s approach through “detuned” resonances. The most relevant resonances and related bifurcations are analyzed, providing quantitative predictions, in the form of energy threshold values, which determine the appearance of the main periodic orbits
ACCIDENTAL FALLS AND IMBALANCE IN MULTIPLE SCEROSIS: DIAGNOSTIC CHALLENGES, NEUROPATHOLOGICAL FEATURES, AND TREATMENT STRATEGIES
No full textLack of balance is common in Multiple Sclerosis (MS) and is among the most disabling symptoms, since it reduces mobility and independence, leads to falls and injuries, and impacts upon overall quality of life. In this research we aimed to report the efforts made to: (i) establish an objective and reliable method to measure imbalance in MS by means of static posturography; (ii) estimate the role of this method in predicting patients at risk of falls; (iii) investigate the neuropathological features leading to imbalance in MS by combining static posturography and conventional / non-coventional magnetic resonance imaging; (iv) verify the effectiveness of visuo-proprioceptive rehabilitation in reducing balance deficit and risk of falls in these patients.Clinical research on patients with multiple sclerosisThis research was partially funded by Associazione Italiana Sclerosi Multipla (FISM grant 26/R/2010
Trattamento Chirurgico dell'Ernia Gastrica Iatale
No full textIl trattamento chirurgico dell'ernia gastrica iatale per via laparoscopica rappresenta, al giorno d'oggi, il gold standard per tale patologia. Verranno analizzate le varie tecniche, evidenziandone le reali indicazioni e risultati
Ultrapotassic lava flows from Colli Albani Volcanic District shed light on the origin of calcite-bearing magmas
No full textThis work reports a detailed petrological, geochemical and experimental study of lava flows belonging to the whole eruptive activity of the Colli Albani Volcanic District (central Italy). Colli Albani lava flows are particularly intriguing due to the occurrence of calcite crystals in the groundmass of some of these products. By exploring still unclear aspects of the origin of the investigated lava flows, the study aims at shedding light on the origin of calcite-bearing magmas at Colli Albani, thus providing inferences on carbonate-bearing magmas from other magmatic systems worldwide.
The detailed microtextural investigation of lava flows has shown that calcite mainly occurs i) interstitially, associated with clinopyroxene, nepheline and phlogopite, ii) in spherical ocelli, associated with nepheline, fluorite and tangentially arranged clinopyroxene, iii) in corona-like reaction zones around K-feldspar xenocrysts. Rarely calcite is enclosed in clinopyroxene xenocrysts and, only in one deposit (the Vallerano lava flow), occurs in amigdalae associated with zeolite.
The observed microtextural features indicate that in all investigated lavas but one (the Vallerano lava flow) calcite is not a hydrothermal phase but crystallized from a carbonate melt when the groundmass was still partially molten (i.e. at temperature above the solidus of the hosting lava flow). The high activity of fluorine in the Colli Albani magmas, recorded by the occurrence of F-rich mineral phases such as amphibole, mica and fluorite, had a key role on the stabilization of calcite at atmospheric pressure and magmatic temperature. The calcite stable isotope values account for a crustal, rather than mantle, origin of the carbonate melt and the calcite trace element patterns are consistent with the melting of limestone fragments ripped from the substrate and entrapped at shallow level into the rising magma.
The phase equilibria experiments performed at variable pressure and temperature, mimicking different possible carbonate contaminants for the magmas, support the crustal, rather than mantle, origin of the contaminating carbonate. In particular, experiments performed using a natural olivine-leucitite (Palazzolo lava flow, representative of Colli Albani parental composition) doped with natrocarbonatite (as mantle contaminant component) produced melilite as liquidus phase and alkali-rich, silica-poor residual glasses. These results, inconsistent with the composition of the Colli Albani natural products, allow ruling out the mantle origin of the contaminant.
Additionally, to better constrain the mantle source of Colli Albani primitive magmas, new Sr and Nd isotope data have been produced. On one hand, the assimilation and fractional crystallization modeling applied to the studied composition shows that the observed Sr and Nd isotope values have been not influenced by limestone assimilation. It would have required, indeed, a too high amount of assimilation to reproduce the observed trend. On the other hand, the progressive decrement of 87Sr/86Sr with the age of the products is consistent with a decrease of the contribution of phlogopite during melting of the metasomatized mantle source. The absence of an appreciable correlation between 143Nd/144Nd and the age of the products can be due to the absence of a Sm-rich phase in the mantle source
"Should I stay (at home) or should I go (to work): individual and contextual antecedents of absenteeism and presenteeism. Evidence from a privatized Italian organization.”
No full textThe present work contributes to the study of attendance behaviors by analyzing the agentic and proactive components of individual behaviors, strongly required in the
today’s work situation in order to facilitate people in handling competition, actively shaping changes and taking advantages from it. In fact, rooted in the social-cognitive theory (Bandura, 1986), the current work stresses the role of self-efficacy in directly and indirectly impacting the decision to take a day-off or to attend work despite unhealthy medical conditions. Additionally, in line with the importance of adopting a longitudinal approach (Mason & Griffin, 2003) and including social dynamics (Johns, 1997) in the study of absenteeism, the current work explores temporal variations in absences and tests how social context can explain changes across time. For this latter purpose, social context has been conceptualized through the perceptions of social
context (PoSC; Borgogni, Dello Russo, Di Tecco, Alessandri, & Vecchione, 2011), operationalized as the individuals’ perceptions of the most relevant social constituencies of the
organization (i.e., immediate supervisor, colleagues and top management) and of their behaviors.
Finally, according to a psychological view of presenteeism (Johns, 2011), the present work investigates whether and how self-initiated change behaviors model the tendency to work if ill, measuring a relatively new construct, job crafting, which designs the physical, cognitive and relational changes that people make in some aspects of their work (Tims, Bakker, & Derks, 2012; Wrzesniewski & Dutton, 2001). Specifically, three studies were designed, presented as follows.
The first study, consistent with social-cognitive theory (Bandura, 1986), aimed to deepen the concurrent role of self-efficacy and job satisfaction in predicting absenteeism, testing both a direct and indirect relation in two different groups of employees, based on their length of service
within the organization.
The second contribution intended to study the dynamic and accrual over time of absence behaviors. It analyzed different absenteeism trajectories over four years of employees who
differed in years of organizational tenure. Moreover, it investigated the impact of social influence on these changes, testing the effect of perceptions of social context (i.e., perceptions of colleagues, immediate supervisor and top management) on absenteeism trajectories.
Finally, the third study focused on presenteeism. It explored the role of self-efficacy and job crafting in shaping the phenomenon and it investigated its consequences on job performance, as rated by supervisors. Moreover, as job crafting is a rather new construct, it explored the
relation between efficacy beliefs and crafting behaviors
IL SISTEMA DEI CONTROLLI INTERNI ED ESTERNI DI FINANZA PUBBLICA
No full textLa ricerca tratta del tema dell’efficacia dei controlli, sia interni che esterni, sugli enti ed organismi pubblici, nonché sulle società pubbliche.
Preliminarmente, occorre notare come, nell’ambito delle discipline giuridico-amministrative e della contabilità pubblica, che studiano ed analizzano le tematiche della Pubblica Amministrazione, sono state elaborate diverse nozioni di “controllo”, anche se tutte riconducibili al medesimo significato. Dopo aver introdotto la nozione di “controllo”, verranno evidenziate le varie definizioni date in ambito dottrinario e giurisdizionale. Nello specifico, mentre i controlli interni sono disciplinati, in parte, da norme risalenti nel tempo, in parte, da norme che, apparse nei primi anni Novanta, sono giunte, con il D.Lgs. n. 286/1999, ad un sufficiente grado di definizione, i controlli esterni traggono origine dall’articolo 100, comma 2, della Costituzione, laddove dispone che “La Corte dei Conti esercita il controllo preventivo di legittimità sugli atti del Governo, e anche quello successivo sulla gestione del bilancio dello Stato. Partecipa, nei casi e nelle forme stabiliti dalla legge, al controllo sulla gestione finanziaria degli enti a cui lo Stato contribuisce in via ordinaria. Riferisce direttamente alle Camere sul risultato del riscontro eseguito”.
Tale forma di controllo in seguito attuata e disciplinata dalla legge 21 marzo 1958, n. 259. Nello specifico, verrà trattato il sistema dei controlli interni e delle sue caratteristiche, con riferimento anche al tema dell’efficacia delle verifiche amministrativo-contabili effettuate dai servizi ispettivi di finanza pubblica.
Verrà data attenzione, inoltre, all’articolo 16 della legge n. 196/2009, il quale stabilisce che deve essere assicurata la presenza di un rappresentante del Ministero dell’Economia e delle Finanze presso i collegi sindacali e di revisione di tutte le amministrazioni pubbliche (con esclusione degli enti territoriali e degli enti e organismi da questi vigilati).
Tale previsione normativa è di notevole importanza; infatti se è vero che il controllo svolto dai collegi è limitato, in quanto la cadenza temporale non consente un controllo approfondito e completo su tutta la gestione, è altrettanto vero che occorrerebbe prevedere effettivi meccanismi di adeguamento rispetto ai rilievi formulati dal Collegio, nel senso di dare un seguito a questi rilievi e non lasciare che “restino solo a verbale”.
La previsione di un rappresentante del M.E.F. in tutti i Collegi di revisione o sindacali delle P.A. assicura “terzietà”, “imparzialità” e “neutralità” alla funzione di controllo, non dismette la veste di soggetto deputato al “controllo della finanza pubblica”, consente al Ministero dell’Economia e delle Finanze di svolgere meglio l’attività di vigilanza e di monitoraggio su tutta l’area della spesa pubblica che rientra nel perimetro del conto consolidato delle Pubblica Amministrazione.
Ci si occuperà delle problematiche del controllo esterno della Corte dei conti sulle società pubbliche e dello stato della giurisdizione in materia di controllo sulla gestione degli enti pubblici economici e società pubbliche, deteminatesi anche a seguito delle privatizzazioni di imprese ed attività economiche.
Dopo aver trattato, quindi, della distinzione tra controlli “esterni” di finanza pubblica (attuati dalla Corte dei Conti) e controlli “interni” di finanza pubblica (effettuati dalla Ragioneria Generale dello Stato), verranno tratte le conclusioni della ricerca, con particolare riferimento alla natura “collaborativa”dei controlli sia interni che esterni, alla necessità di una loro effettiva integrazione, alle presunte ipotesi di duplicazione degli stessi ed al loro grado di autorevolezza ed incisività