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con la sindrome dell'ovaio policistici (PCOS): Stato dell'arte ed attualità nella pratica clinica."
No full textAbstract
Il concetto di base della maturazione in vitro (IVM) degli ovociti nella pratica clinica consiste nella raccolta degli ovociti immaturi da piccoli follicoli antrali prima dell’ ovulazione spontanea e quindi lasciati maturare in vitro.
La follicologenesi in vitro non rappresenta solo la possibilità di ampliare la disponibilità di gamete femminili in termini di numero degli ovociti fecondabili ma anche un modello entro cui comprendere i complessi meccanismi che regolano il sinergico sviluppo fra follicolo e gamete femminile.
Più approfondita comprensione della complessa orchestrazione della maturazione nucleare e citoplasmatica dell’ovocita basata su ricerca di basi sugli ovociti animali ha permesso di dare l’inizio all’ applicazione clinica della tecnica IVM nella procreazione medicalmente assistita.
I vantaggi nella pratica clinica della IVM sono stati ampiamente riconosciuti, in primo luogo la mancanza dell’utilizzo delle gonadotropine per la stimolazione ovarica controllata e di conseguenza l’assenza del rischio dell’ iperstimolazione ovarica soprattutto nelle donne con la sindrome dell’ovaio policistico (PCOS).
Tuttavia, la maturazione in vitro non è ancora del tutto ottimizzata universalmente nei vari centri di riproduzione medicalmente assistita ma numerosi studi hanno dimostrato che il numero degli ovociti ottenuti da donne con PCOS sono numericamente più consistente rispetto alle donne non PCOS che rappresenta un vantaggio in termine di percentuale di tasso di gravidanza.
L'ovocita umano maturo è l'ingrediente chiave per la fertilità, altamente specializzato nel processo dell’ovogenesi che comprende la crescita, la differenziazione e la maturazione del gamete femminile.
Nel sistema riproduttivo dei mammiferi, lo sviluppo degli ovociti avviene all'interno del microambiente altamente specializzato di un follicolo ovarico. Il follicolo ha il compito di facilitare il complesso e delicato processo dell’ ovogenesi.
la differenziazione degli ovociti dipende in ultima analisi dalla cooperazione e coordinamento della funzione del follicolo antrale nel suo complesso. Così, per capire la differenziazione dell’ovocita , dobbiamo chiarire le funzioni dei compartimenti dei follicoli antrali nonché il loro rapporto reciproco.
Ulteriori sforzi devono continuare a svelare come i componenti del microambiente follicolare guida la differenziazione degli ovociti.
Metodo di ricerca per l’ identificazione dello studio :
Una revisione della letteratura scientifica sulla maturazione in vitro dell’ovocita come tecnica di riproduzione assistita , ed in particolar interesse nelle donne con la sindrome dell’ovaio policistico non sottoposte ad una stimolazione ovarica controllata. . La database elettronica della Biblioteca della seconda facoltà di Medicina e Chirurgia dell’ Università di Roma ‘ La Sapienza ’ che comprende PubMed, the Reproductive Health Library e the Cochrane Library è stata consultata per tutta la review .
Keywords incluse nella ricerca : Sindrome dell’ovaio policistico , maturazione in vitro dell’ovocita , infertilità femminile e procreazione medicalmente assistita
Kinetic approach to pair production in strong electric fields and to transparency of relativistic outflows
No full textIn my thesis I present the theoretical study of two physical phenomena in plasma physics, namely (a) electron-positron pairs production in strong electric fields and (b) transparency of relativistic outflows.
From the theoretical point of view, both these systems have been long under study. The pair production due to Schwinger effect is one of the key problems in modern Quantum Field Theory. Currently an international effort is underway aiming at generation of ultrahigh intensities of laser fields and thereby creating electric fields near the critical value for the pair production. There is an ongoing debate on whether the critical electric field can be potentially reached in these experiments. In the literature many theoretical studies of pair production can be found. However very few of them account for back reaction of created pairs on the initial electric field. Concerning transparency of relativistic outflows, there is currently a consensus in the literature that emission produced by the photosphere of relativistically expanding plasma should be present in all gamma-ray bursts (GRBs). The intensity of this photospheric component emission may be weak compared to the total intensity of the GRB. However when detected, this emission may provide unique information on physical properties of relativistic outflows which produce GRBs.
Even though very different in what concerns their macroscopic features, the microphysics of both phenomena (a) and (b) can be described in detail using a common method. This is what we aim to do in the study of pairs creation and photospheric emission using a theoretical approach based on Relativistic Kinetic Theory (RKT). One of the main motivations behind this strategy is related to the possibility, given by such theory, to study physical systems out of equilibrium from a very general point of view. To do that we solve the Relativistic Boltzmann Equation (RBE) with exact collision integrals corresponding to relevant microscopic processes, taking into account the anisotropy of the distribution function in the phase space.
One one hand, with this technique we are able to describe the evolution in time of the initially out of equilibrium system of electric field and electron-positron-photon plasma up to thermalization. On the other hand when transparency of relativistic outflow is considered, the opposite behavior of departure of electron-photon plasma from thermal equilibrium can be followed.Specific Grant Agreement 2010-1816 from the EACEA of the European Commissio
DEVELOPMENT OF ANALYTICAL METHODOLOGIES FOR THE MONITORING OF THE ATMOSPHERIC PARTICULATE MATTER
No full textThe present research project focused on the development of analytical methodologies for the monitoring of the atmospheric Particulate Matter.
Particulate matter (PM) is one of the main pollutants exceeding the ambient standards for air quality in Europe. In Italy, the mass concentration standards are overcome many times per year, mainly due to the unfavourable meteorological conditions (especially in the Po Valley regions) and to the transportation of the air masses coming from the Sahara Desert (Southern and Central regions). The direct and indirect influence of the PM on human health, global climate change and reduced visibility have led to numerous studies in the last past decades, focusing upon its complex composition, toxicology and the source attribution. The particulate matter is constituted by an heterogeneous mix of components, characterized by a variable chemical composition and different chemical-physical properties that greatly influence its deposition and distribution. For these reasons nowadays it is still very difficult to develop efficient abatement strategies to protect both human health and environment. To achieve these specific objectives it is necessary to focus on some issues that are still not resolved, by taking advantage of both the analytical chemistry and the statistical methods.
One of the “open” issues is the determination of water content in PM. Water plays an important role in the formation of the secondary species starting from gaseous precursors. It is well known that these species undergo gas-particle equilibria influencing the sampling phase and altering the results of the monitoring campaigns but, given the great variability of the measured concentrations, to date, a clear interpretation of these processes has still not been found. More information could be obtained by determining the water content in PM. Moreover, the knowledge of the water amount sampled together with the atmospheric particles on appropriate media could be very useful to establish the water influence on the PM mass concentration as well. Till now, the water determination has been carried out mostly by indirect methods estimating the water adsorbed on not-sampled particles. During the present project a simple method to determine water in PM samples has been optimized and validated, based on the Karl-Fisher theory. The potentialities of the thermal desorption were also explored to study the different types of water linked to the particles. After the validation, this methodology has been then applied to real PM samples collected in geographical areas characterized by several emission sources (traffic, industries, etc.), demonstrating that water is a relevant component of the PM and it influences in a significant way the PM mass concentration especially in samples very rich of secondary inorganic compounds or natural sand. Moreover the type of water present in the atmospheric particles is strictly dependent on the PM chemical composition.
The second part of this project concerned the measurements of the PM at high temporal resolution. Sampling and analysis of PM in real time at high time resolution allow to have some precious information about the temporal variability of the atmospheric pollutants’ concentration, that usually are lost with the 24-hours sampling time. Our attention was focused on a new device able to sample and analyze in real time the atmospheric inorganic ions, the Particle Into Liquid Sampler coupled with the Ion Chromatography (PILS-IC). The instrument in its original configuration is affected by some limits, the high detection limit values that make difficult to apply it in low polluted areas and the low time resolution due to the analysis of the solution contained in the chromatographic loop only at the injection time into the column. These limits were solved modifying the original instrumental configuration, inserting a pre-concentration system. The new optimized system was then validated and applied to a monitoring campaign. The results have been compared with those obtained by other analytical techniques aimed to measure the same species, showing good performance of the new system. The data obtained by using this system were also useful to understand the chemical form in which the ions were present in the atmosphere at the sampling time and allowed to isolate some hot spot pollution events.
The last part of the present project has been carried out at the University of Birmingham (United Kingdom) under the kindly supervision of Prof. Roy M.Harrison and focused on the traceability of the PM emission sources. The knowledge of the emission sources is one of the main objectives in the PM studies, as it is necessary for developing efficient abatement strategies. The Source Apportion techniques are very helpful to reach this objective. In particular, the Positive Matrix Factorization receptor model (PMF) was applied to identify and quantify the PM sources at an industrial area of the Po Valley. This model is very useful to manage large databases coming from the chemical analysis of PM collected during long monitoring campaigns and is able to determine the main PM sources by looking at the correlation of the variables (measured species) at the monitored receptor sites. The variables to process by the model have been chosen with the support of a detailed chemical characterization of PM using a fractionation methodology based on the elemental solubility. The main PM sources in the Po Valley have been identified with the secondary nitrate and the biomass burning, although the industrial nature of the monitored area.
Because of the wideness of the topics they will be treated in separated chapters
Large scale and small scale turbulence in an orifice jet: experimental study based on planar and volumetric techniques
No full textS'en remettre à un spécialiste de la santé mentale. Regards croisés sur des services publics en France et en Italie
No full textThis research proposes a pragmatic reinterpretation of delegation of care in mental health public policy. The purpose of the following comparative analysis is to analyse how, in France and Italy, political actors, professionals and publics tacked part at this collective action form 1960 to 2010. At first, the thesis analyses the texts of all politicians who instituted the birth of services "mental health" in the countries concerned. These texts are analysed taking into account the views of professionals in these services from a corpus composed of journal articles. Further investigation to analyse the speech of actors directly or indirectly involved in the delegation of care (patients and its families), is presented in a second time. Performed first in Italy and then in France, further investigation helps to know how people have participated in the delegation of psychiatric care. The study shows how a priori the opposite way, the French and Italian cases lead their public policy: respectively, "fight against mental illness" versus "protecting mental health." These modes are really only two variants of the same political risk, which aims both to neutralize the other, to prevent what is seen as a threat to the community or individuals. By maintaining the psychiatric hospital, the French model is aimes to eliminate mental illness in individuals, while the development of the community services, the Italian model aims to protect the community from risks related to mental health
Materiali per la qualificazione e la riqualificazione urbana: le aree di margine
No full textLa ricerca si articola intorno alla considerazione di un ambito urbano, quello delle aree di margine tra aree edificate ed aree verdi. La tesi vuole mettere in luce come, forse, sia possibile liberare le aree oggetto di studio dal loro stato di considerazione "marginale" in senso negativo e caricarle di un significato di "centralità", non in termini localizzativi tradizionalmente intesi, ma nella direzione della loro importanza nelle dinamiche di trasformazione urbana.
Si ritiene che questo percorso di ricerca non possa astenersi dalla considerazione della profonda crisi che sta attraversando la disciplina dell'urbanistica nel gestire le trasformazioni del territorio. La crisi è un momento difficile, in cui le forze e gli strumenti che si hanno a disposizione sembrano non essere più efficaci nel gestire ciò che è intorno e i sentimenti prevalenti sono quelli del disorientamento e dell'insicurezza. Ma la crisi è anche una possibilità di prendere coscienza di cose che forse non hanno funzionato da tempo, per capire se e in quale modo è possibile ricomporre un equilibrio o ricostruirne uno nuovo. La crisi può essere intesa come uno stato di forte difficoltà, ma allo stesso tempo un'importante possibilità di ripensarsi, un'opportunità. Il percorso di ricerca prende le mosse da questa considerazione individuando proprio nelle aree urbane di margine l'emblema del duplice livello del significato di crisi: aree dense di problematiche ma anche ricche di opportunità.
La tesi, dunque, partendo dalle criticità che investono le aree urbane di margine, cerca di indagarne e rintracciarne i valori, le risorse, i caratteri vitali … le opportunità presenti in esse di innescare azioni volte a realizzare nuove e migliori immagini di città. E rispetto a queste opportunità, la tesi tenta di ipotizzare processi, comprendere azioni, tracciare percorsi tali da illuminarle e da renderle visibili e significative nelle future conformazioni territoriali
Neuro-cognitive and social components of dyadic motor interactions revealed by the kinematics of a joint-grasping task
No full textThis thesis describes a PhD project is based on the notion that we live our whole life dipped into an interactive social environment where we observe and act together with others and where our behavior is influenced by first sight impressions, social categorizations and stereotypes which automatically and unavoidably arise during interactions. Nevertheless, the bidirectional impact of interpersonal coding on dyadic motor interactions has never been directly investigated. Moreover, the neurocognitive bases of social interaction are still poorly understood. In particular, in every-day dyadic encounters we usually interact with others in non-imitative fashions (Sebanz et al. 2006), challenging the hypothesis of a direct matching between action observation and action execution within one system (“common coding approach”, Prinz 1997), which is instead supported by neurophysiological data on the so called “mirror neurons”(Rizzolatti and Sinigaglia 2010) which fire both during action execution and observation of similar actions performed by others. Suggestion is made that what characterizes joint action is the presence of a common goal (i.e. the “shared” goal, Butterfill 2012) which organizes individuals’ behaviour and channel simulative processes.
During her PhD, Lucia Sacheli developed a novel interactive scenario able to investigate face-to-face dyadic interactions within a naturalistic and yet controlled experimental environment, with the aim to build a more coherent model of the role of simulative mechanisms during social interaction and on the role of socio-emotional variables in modulating these processes. This scenario required pairs of participants to reciprocally coordinate their reach-to-grasp movements and perform on-line mutual adjustments in time and space in order to fulfill a common (motor) goal.
So far, she demonstrated by means of kinematic data analysis that simulation of the partner’s movement is task-dependent (Sacheli et al. 2013) and modulated by the interpersonal relationship linking co-agents (Sacheli et al. 2012) and by social stereotypes as ethnic biases (Sacheli et al. under review).
Moreover, she used the same scenario to investigate the different contribution of the parietal and frontal nodes of the fronto-parietal “mirror” network during joint-action by means of Transcranial Magnetic Stimulation combined with analysis of kinematics