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Forme del saggio alla prova del genere nella scrittura teorico-critica di area femminista italiana (1974-1991)
No full textLa tesi propone dei percorsi di rilettura della saggistica di area femminista italiana degli anni Settanta e Ottanta del Novecento
attraverso l'analisi delle sue invenzioni retorico-espressive.
Procedendo alla messa in questione "teorica" del saggio come forma e della forma saggio come genere letterario, si è considerato il saggio teorico-critico delle donne un luogo di elaborazione di dialogo e soggettività, un laboratorio nel quale sono stati forzati i limiti del sistema dei generi letterari in funzione di esigenze di riproduzione di un vissuto mai "contenuto" prima, uno spazio di riflessione su un'esperienza politica e intellettuale e di progettazione di una rivoluzione profonda dello sguardo e dell'approccio all'intero sistema di valori che presiede alla costituzione del canone del sapere.
Attraverso la ricomposizione di un quadro bibliografico che evidenziasse la presenza e i contorni della saggistica femminista italiana e la posizione di alcune questioni intorno alle possibili riletture storiografiche della vicenda femminista, si sono letti i saggi di alcune autrici, tra le altre: Melandri, Lonzi, Fraire, Muraro, Rossanda, Passerini
VEGF-D e caratteri anatomo patologici tumori gastrointestinali
No full textLa diffusione metastatica è il principale fattore prognostico negativo nelle patologie neoplastiche ed il sistema linfatico risulta essere tra le prime vie di diffusione a distanza delle cellule neoplastiche.[1]
Le glicoproteine VEGF-C e VEGF-D sono membri della famiglia del Vascular Endothelial Growth Factor (VEGF) riconosciuta come regolatore della proliferazione del sistema linfatico durante l’embriogenesi e nei processi patologici come gli stati infiammatori, i disordini del sistema linfatico e la diffusione metastatica dei tumori maligni. [1-3] [2-5]
Le neoplasie solide in grado di esprimere VEGF risultano favorite nella crescita in quanto l’aumentato metabolismo delle cellule tumorali necessita di un maggiore apporto energetico e dunque di una maggiore vascolarizzazione. Ne consegue un aumento del potenziale metastatico.[6]
Secondo i più recenti studi la famiglia VEGF è composta da 5 citochine nei mammiferi: VEGF, PIGF (platelet induced growth factor), VEGF-B, VEGF-C, VEGF-D.[4-8] (Tab. Ia, Ib).[7-11]
I sottotipi VEGF-C e VEGF-D sono stati identificati come ligandi del recettore linfatico endoteliale VEGFR3 così come per il recettore dell’endotelio vascolare VEGFR2. [13-15] [12-15]
Sia il VEGF-C che il VEGF-D sono capaci di indurre la proliferazione e la migrazione di cellule linfatiche endoteliali in vitro. [16] [16]
Studi sperimentali e clinico patologici hanno correlato l’asse VEGF-C, VEGF-D/VEGFR3 alla diffusione linfatica cosi come alla prognosi di diversi tumori solidi nell’uomo. [17]
E’ stato inoltre dimostrato come il VEGF del sottotipo “D” sia responsabile della aumentata linfoangiogenesi.[9-12] [18-21]
La maggior parte di questi dati sono stati raccolti tramite lo studio dei campioni anatomopatologici post resezione con intento curativo.[6;17]
Nel tentativo di ottenere le medesime informazioni prima dell’eventuale trattamento sia per prognosi che per indirizzare verso la giusta terapia, è stato sviluppato un metodo immunoistochimico per le neoplasie solide dell’apparato gastrointestinale (stomaco-esofago-colonretto). [22-23]
Infatti lo studio quantitativo del VEGF-C e VEGF-D in campioni di sangue periferico risultano utili come possibile applicazione del come biomarker preoperatorio in merito alla diffusione metastatica linfonodale e contribuire allo staging preoperatorio delle suddette neoplasie solide del tratto gastrointestinale.
La correlazione tra l’asse VEGFC, VEGFD ed il VEGFR3 è dimostrata da diversi studi in molti tumori solidi. [17-19] [24-26]
La maggior parte dei studi ha confermato la correlazione positiva tra la maggior espressione del growth factor e fattori oncologici sfavorevoli. [20-23] [27-30]
Scopo della ricerca è individuare una correlazione tra l’espressione del VEGF-D ed alcuni parametri anatomo-patologici caratteristici delle neoplasie in studio
DEVELOPMENT OF NEW ANALYTICAL METHODS AND APPLICATION OF CHEMOMETRIC TOOLS IN FLAVOUR RESEARCH
No full textIn food science, there are several ways of defining quality, and perhaps there is no single universal definition that adequately satisfies all situations; in general terms, quality is defined as “the combination of attributes or characteristics of a product that have significance in determining the degree of acceptability of that product by the consumer”.
The aim of this Thesis lies mostly on food quality field: indeed, one of the most important criteria for consumer acceptance of food is flavour.
Due to the increasing demand of high quality and enjoyable foods, the need for methodologies enabling a better understanding of flavour has arisen: chemical analysis is a valuable way of studying volatile composition of different food matrices, and very sophisticated instrumentations are available nowadays, but almost always there is the need of clean-up/concentration steps before such analysis.
Moreover, when volatile compounds are present in traces (ppb or even ppt), their detection and identification require the development of analytical tools which can tackle these difficult tasks: in the past, they were largely detected with insufficient performances or even undetected, due to the inadequacies in old-fashioned analytical techniques.
Hence, in this work novel, simple, rapid, and “environmental friendly” sample preparation methods were implemented, which coupled really well with Thermal Desorption – Gas Chromatography – Mass Spectrometry (TD-GC-MS), following also the Green Chemistry requirements.
It was investigated the use of Stir Bar Sorptive Extraction (SBSE) technique, showing that it is extremely suited for troublesome analytical challenges such as isolation of volatile compounds from several food matrixes, including both processed (beverages, yogurts) and fresh foods (fruits and vegetables); the application of this technique was thus broaden in new complex matrices (e.g. yogurts).
This sorptive sample preparation showed good performances for practical, real-life analytical problems, which cannot easily be solved by alternative and time-consuming approaches: it allows an effective extraction of volatiles in the trace range, and a rich aromatic profile may be pursued using optimized conditions.
SBSE has proven to be a technique that can offer high and reproducible extraction recoveries for the complex matrices under study; it was also characterized by ease of use, good repeatability and robustness.
In addition, Headspace Solid Phase Micro-Extraction (HSPME) was used for sampling volatile from the headspace of olive oil samples: the point is that enrichment for gaseous samples is more difficult; particularly the analysis of polar compounds is an analytical problem that cannot be addressed adequately by conventional techniques, i.e. distillation, dynamic headspace, etc.
Using this other solventless extraction technique, a reliable analytical method for the determination of a broad range of volatiles in olive oil was developed.
Then, looking also at volatile release, which is a complementary task for a better understanding of interactions among food components, volatiles and in-vivo behavior, a real-time instrumentation, Proton Transfer Reaction - Mass Spectrometry (PTR-MS), was used to follow these rapid changing phenomena, without any need of sample preparation or calibration.
The application of these analytical methods was then combined with the use of suitable chemometric techniques such as PCA (Principal Component Analysis), ASCA (Analysis of Variance combined to Simultaneous Component Analysis), MIXTURE DESIGN MODELING, and PLSR (Partial Least Squares Regression).
We truly think that nowadays chemometrics is unavoidable and of utmost importance, when scientists have to deal with multivariate datasets, and when robust “chemical-driven” modeling of complex phenomena is needed
INTEREST RATE PASS-THROUGH AND CREDIT SPREAD IN NEW KEYNESIAN MODELS. THEORETICAL AND EMPIRICAL RELEVANCE
No full textThe behavior of banks and the determination of retail interest rates have taken a prominent
role after the recent financial crisis: high levels of the cost of credit and quantity rationing are
characterizing the actual economic environment. Monetary policy has sought to address the setting
of bank rates by continuous operations on the monetary policy rate. Nevertheless, the adjustment
of bank rates has not been complete.
The aim of this dissertation is to show that the incomplete pass-through of policy rate changes
on the loan rate may depend also on market frictions, in particular those existing in the credit
market. To this aim, we present three self-contained but highly correlated papers in which we
discuss the role of these frictions, and their interplay with those existing in the labor market, on
the size of the interest rate pass-through and its relevance in shaping business cycle dynamics. The
study of interest rate dynamics also allows us to focus on the cyclical behavior of the credit spread,
which is often used as a leading indicator of the economic activity. In order to shed light on these
issues, we employ a New Keynesian framework (Walsh, 2003) which offers a convenient setting for
monetary policy analysis. What is relevant in this model is the so-called “cost channel” that links
the current and the expected future real marginal costs of the productive sector of the economy
with inflation and then with the business cycle dynamics. If, as in this work, the loan interest rate
enters the definition of marginal costs, it can affect the dynamics of the main macroeconomic and
financial variables.
Theis dissertation is organized as follows.
In chapter 1, after reporting the empirical and theoretical literature on the interest rate passthrough
and the credit spread, we present a critical survey that uses Bayesian techniques to compare
models which explain the interest rate on loans on the basis of different theoretical mechanisms.
In particular, we propose a model - to be more detailed in chapter 2 - in which credit market
frictions are modeled by the search and matching technology. We conclude that the specification
which benefits from the most favorable evidence is one in which the banking lending rate depends
on its past value, as well as on credit market frictions.
In chapter 2 we describe a New Keynesian model with search and matching frictions in the
credit market and we derive a definition of the banking lending rate which depends on the aggregate
credit market tightness. We estimate and simulate the model with respect to monetary, technology
and credit shocks and we highlight both the incompleteness of the interest rate pass-through and
the countercyclical behavior of the credit spread. We also show the importance of the bargaining
power of banks to explain the degree of (in)completeness of the interest rate adjustment, as well
as the (more or less) countercyclical behavior of the credit spread.
In chapter 3 we study the interplay of search and matching frictions in the labor and in the
credit markets, focusing on monetary policy disturbances. We confirm that the incompleteness of
the interest rate pass-through depends on some deep parameters, such as the relative bargaining
powers and the search costs of agents. By comparing the model outcomes with those which
obtain with parameter values generating a complete pass-through, we show that the transmission
of monetary policy shocks to output and inflation is more relevant than suggested by the recent
literature, even though the presence of credit market frictions has a moderation effect on the main
macroeconomic dynamics
Il "Libro del Cortegiano". Studi per l'edizione critica
No full textStudio del ms. Laurenziano Ashburnhamiano 409. Collazione del ms. Laurenziano con l'editio princeps (Venezia, 1528). Approfondimento degli aspetti ecdotici, filologico-linguistici, bibliografici e storico-culturali. Repertorio bibliografico dell'opera: edizioni italiane e straniere dal 1528 al 1900
ADATTAMENTO AL CAMBIAMENTO CLIMATICO: ORIZZONTI PER LA PIANIFICAZIONE
No full textLa ricerca affronta il tema del rapporto tra questione climatica e pianificazione territoriale, con particolare riferimento al ruolo che quest’ultima può svolgere nei processi di adattamento al cambiamento climatico. La questione climatica, ed in particolare l’adattamento al cambiamento climatico, affermano la necessita di rafforzare la consapevolezza che cambiamento e variabilità sono caratteristiche fondanti dei sistemi umani e naturali e che questi, in quanto sistemi complessi, possono dare luogo a trasformazioni i cui esiti sono carichi di incertezza.
L’adattamento al cambiamento climatico rappresenta perciò in questa ricerca un caso particolare di un problema più vasto, che da sempre riguarda da vicino la pianificazione: il problema della variabilità e dell’incertezza dei sistemi socio-ecologici (SES). Di fronte a questa incertezza e variabilità la pianificazione non sempre e riuscita a dare risposte adeguate, tendendo spesso ad irrigidire i sistemi che pianifica e dunque a trascurare o a non saper “trattare” la loro complessità, proponendo visioni e scenari tendenzialmente statici.
La tesi conseguentemente sostenuta è che una pianificazione che non sia dotata di un certo grado di flessibilità non solo non sia adeguata a rispondere al bisogno di adattamento climatico ma sia strutturalmente inadatta, e quindi in qualche modo inefficace, a gestire sistemi complessi quali quelli urbani e territoriali che sono per loro natura in trasformazione; e che anzi porti ad un loro irrigidimento rendendoli più esposti a ”soffrire” a seguito di sollecitazioni endogene o esogene.
In relazione alla tesi esposta gli obiettivi assunti dalla ricerca sono due: il primo e quello di incrementare, anche in maniera indiretta, la capacita di adattamento al cambiamento climatico di un sistema urbano-territoriale attraverso la pianificazione; il secondo e rappresentato dalla comprensione di come a tale scopo possa essere introdotto nella pianificazione un certo grado di flessibilità
L'antispagnolismo nella letteratura italiana: storiografia e testi
No full textL'antispagnolismo in Italia tra storiografia (XVIII-XIX sec.) e letteratura (XVI-XVII sec.); antispagnolismo e decadenza nel Settecento; antispagnolismo tra libertà e indipendenza nazionale nell'Ottocento; la tematizzazione dell'antispagnolismo nella letteratura: pensiero politico e scelte stilistiche di Traiano Boccalin
Dottore
No full textThe PhD project is based on 3D geometric morphometrics analysis (GMM) of the rear portion of the human cranium (the area surrounding the posterior fossa) in fossil and recent samples. The aim is not simply to quantify the differences in occipital morphology between human species and lineages, but also to relate these differences to the phenomenon of encephalization, which should be regarded as the primary determinant for the variability in cranial morphology within the genus Homo, from both the ontogenetic and evolutionary perspectives.
With the emergence of the genus Homo at the beginning of the Early Pleistocene, the non-allometric increase of cerebral volumes (encephalization) – and the subsequent development of the cranium along differential growth vectors (mainly antero-posterior directed) – has led to disturbance of the postural equilibrium between the skull and the spine that occurred in the Late Miocene with the transition to bipedalism and its maintenance among the australopithecines. This disturbance resulted in functional responses, both direct and indirect, in terms of increased instability in the patterns of cranial ossification (due to differential brain growth, highlighted by the presence of ontogenetic stress indicators such as sutural ossicles on the rear braincase) and in the increase and rearrangement of the nuchal muscles that supports and rotates the skull on the spine. The increase in muscle masses has lead in many fossil human species (e.g. Homo erectus , Neanderthals) to the occurrence of large insertions and associated bony structures such as tori, ridges and pits. Only with the emergence of our species, in consequence of the achievement of a more globular cranial shape and moving of the nuchal muscles forward and beneath the cerebral and cerebellar volumes, a new and more stable head balance is regained.
Within this evolutionary and developmental melieux, the occurrence and distribution of cranial discrete traits known as hypostotic features (interpreted as an expression of "ontogenetic stress") versus hyperostotic feature, are evaluated in various hominin OTUs by multivatiate statistics. Different patterns are observed in the comparison between Middle Pleistocene samples from Africa, Asia and Europe. Using 2block partial least-square analysis, the non-metric variables (discrete traits) are compared to changes in morphology of the cranial vault recorded by 3D geometric morphometrics. These differences appear to be consistent with geographically-distinct trajectories of encephalization. In this framework, the peculiar (i.e., globular) cranial morphology of H. sapiens emerges from the fossil record of late H. heidelbergensis in Africa, which is characterized by a pattern of "ontogenetic stress" affecting the mid-lateral regions of the cranial vault (in relationship with the expansion, elevation and bending of the parietal lobes of the brain). This suggests a sharp structural reorganization in H. sapiens, which minimises the "ontogenetic stress" and allows to recover a morpho-functional balance, combining high degrees of encephalization with a radial distribution of expansion forces that act on the cranial vault. By contrast, in examining the transition in Europe from H. heidelbergensis to H. neanderthalensis, the analysis carried out in this thesis supported the notion that the increased encephalization – involving first the occipital region, and then the biparietal vault – is associated with the maintenance of a plesiomorphic architecture in the cranial (and encephalic) morphology, with increased instability in growth and osteogenetic processes, as shown by the extreme levels of hypostosis recorded among the Neanderthals.
The influence of the muscular loading forces acting on the external surface of the squama of the occipital (on the nuchal scale in particular) considered as the most powerful external “constrains” in relationship with the occipital interspecific shape variability, are also considered by finite element analysis (FEA)
Development of Code and Phase Tracking Algorithms for GNSS signals in low C/N and high dynamics scenarios
No full textGlobal Navigation Satellite Systems (GNSS) receivers working in high dynamic situations usually exhibit poor tracking performance, especially in attenuated signals scenarios. Classic Phase Lock Loops (PLL) are suboptimal in compensating effects of noise and dynamics simultaneously. One solution consists in process and noise modeling with an iterative estimation methodology like the Kalman filter and its nonlinear implementations.
Purpose of this study is to compare the performance of the Extended Kalman Filter (EKF) approach to the more innovative Unscented Kalman filter (UKF), through the implementation of a complete multi-constellation software receiver (RF front end, acquisition, tracking, navigation message decoding and position computation sw modules). A feedback strategy will be described as well as simulation and real time results. Preliminary results show good performance of the new approach if compared to the classic EKF solution