5 resultados para Assignments
em AMS Tesi di Dottorato - Alm@DL - Università di Bologna
Resumo:
The humans process the numbers in a similar way to animals. There are countless studies in which similar performance between animals and humans (adults and/or children) are reported. Three models have been developed to explain the cognitive mechanisms underlying the number processing. The triple-code model (Dehaene, 1992) posits an mental number line as preferred way to represent magnitude. The mental number line has three particular effects: the distance, the magnitude and the SNARC effects. The SNARC effect shows a spatial association between number and space representations. In other words, the small numbers are related to left space while large numbers are related to right space. Recently a vertical SNARC effect has been found (Ito & Hatta, 2004; Schwarz & Keus, 2004), reflecting a space-related bottom-to-up representation of numbers. The magnitude representations horizontally and vertically could influence the subject performance in explicit and implicit digit tasks. The goal of this research project aimed to investigate the spatial components of number representation using different experimental designs and tasks. The experiment 1 focused on horizontal and vertical number representations in a within- and between-subjects designs in a parity and magnitude comparative tasks, presenting positive or negative Arabic digits (1-9 without 5). The experiment 1A replied the SNARC and distance effects in both spatial arrangements. The experiment 1B showed an horizontal reversed SNARC effect in both tasks while a vertical reversed SNARC effect was found only in comparative task. In the experiment 1C two groups of subjects performed both tasks in two different instruction-responding hand assignments with positive numbers. The results did not show any significant differences between two assignments, even if the vertical number line seemed to be more flexible respect to horizontal one. On the whole the experiment 1 seemed to demonstrate a contextual (i.e. task set) influences of the nature of the SNARC effect. The experiment 2 focused on the effect of horizontal and vertical number representations on spatial biases in a paper-and-pencil bisecting tasks. In the experiment 2A the participants were requested to bisect physical and number (2 or 9) lines horizontally and vertically. The findings demonstrated that digit 9 strings tended to generate a more rightward bias comparing with digit 2 strings horizontally. However in vertical condition the digit 2 strings generated a more upperward bias respect to digit 9 strings, suggesting a top-to-bottom number line. In the experiment 2B the participants were asked to bisect lines flanked by numbers (i.e. 1 or 7) in four spatial arrangements: horizontal, vertical, right-diagonal and left-diagonal lines. Four number conditions were created according to congruent or incongruent number line representation: 1-1, 1-7, 7-1 and 7-7. The main results showed a more reliable rightward bias in horizontal congruent condition (1-7) respect to incongruent condition (7-1). Vertically the incongruent condition (1-7) determined a significant bias towards bottom side of line respect to congruent condition (7-1). The experiment 2 suggested a more rigid horizontal number line while in vertical condition the number representation could be more flexible. In the experiment 3 we adopted the materials of experiment 2B in order to find a number line effect on temporal (motor) performance. The participants were presented horizontal, vertical, rightdiagonal and left-diagonal lines flanked by the same digits (i.e. 1-1 or 7-7) or by different digits (i.e. 1-7 or 7-1). The digits were spatially congruent or incongruent with their respective hypothesized mental representations. Participants were instructed to touch the lines either close to the large digit, or close to the small digit, or to bisected the lines. Number processing influenced movement execution more than movement planning. Number congruency influenced spatial biases mostly along the horizontal but also along the vertical dimension. These results support a two-dimensional magnitude representation. Finally, the experiment 4 addressed the visuo-spatial manipulation of number representations for accessing and retrieval arithmetic facts. The participants were requested to perform a number-matching and an addition verification tasks. The findings showed an interference effect between sum-nodes and neutral-nodes only with an horizontal presentation of digit-cues, in number-matching tasks. In the addition verification task, the performance was similar for horizontal and vertical presentations of arithmetic problems. In conclusion the data seemed to show an automatic activation of horizontal number line also used to retrieval arithmetic facts. The horizontal number line seemed to be more rigid and the preferred way to order number from left-to-right. A possible explanation could be the left-to-right direction for reading and writing. The vertical number line seemed to be more flexible and more dependent from the tasks, reflecting perhaps several example in the environment representing numbers either from bottom-to-top or from top-to-bottom. However the bottom-to-top number line seemed to be activated by explicit task demands.
Resumo:
The present work tries to display a comprehensive and comparative study of the different legal and regulatory problems involved in international securitization transactions. First, an introduction to securitization is provided, with the basic elements of the transaction, followed by the different varieties of it, including dynamic securitization and synthetic securitization structures. Together with this introduction to the intricacies of the structure, a insight into the influence of securitization in the financial and economic crisis of 2007-2009 is provided too; as well as an overview of the process of regulatory competition and cooperation that constitutes the framework for the international aspects of securitization. The next Chapter focuses on the aspects that constitute the foundations of structured finance: the inception of the vehicle, and the transfer of risks associated to the securitized assets, with particular emphasis on the validity of those elements, and how a securitization transaction could be threatened at its root. In this sense, special importance is given to the validity of the trust as an instrument of finance, to the assignment of future receivables or receivables in block, and to the importance of formalities for the validity of corporations, trusts, assignments, etc., and the interaction of such formalities contained in general corporate, trust and assignment law with those contemplated under specific securitization regulations. Then, the next Chapter (III) focuses on creditor protection aspects. As such, we provide some insights on the debate on the capital structure of the firm, and its inadequacy to assess the financial soundness problems inherent to securitization. Then, we proceed to analyze the importance of rules on creditor protection in the context of securitization. The corollary is in the rules in case of insolvency. In this sense, we divide the cases where a party involved in the transaction goes bankrupt, from those where the transaction itself collapses. Finally, we focus on the scenario where a substance over form analysis may compromise some of the elements of the structure (notably the limited liability of the sponsor, and/or the transfer of assets) by means of veil piercing, substantive consolidation, or recharacterization theories. Once these elements have been covered, the next Chapters focus on the regulatory aspects involved in the transaction. Chapter IV is more referred to “market” regulations, i.e. those concerned with information disclosure and other rules (appointment of the indenture trustee, and elaboration of a rating by a rating agency) concerning the offering of asset-backed securities to the public. Chapter V, on the other hand, focuses on “prudential” regulation of the entity entrusted with securitizing assets (the so-called Special Purpose vehicle), and other entities involved in the process. Regarding the SPV, a reference is made to licensing requirements, restriction of activities and governance structures to prevent abuses. Regarding the sponsor of the transaction, a focus is made on provisions on sound originating practices, and the servicing function. Finally, we study accounting and banking regulations, including the Basel I and Basel II Frameworks, which determine the consolidation of the SPV, and the de-recognition of the securitized asset from the originating company’s balance-sheet, as well as the posterior treatment of those assets, in particular by banks. Chapters VI-IX are concerned with liability matters. Chapter VI is an introduction to the different sources of liability. Chapter VII focuses on the liability by the SPV and its management for the information supplied to investors, the management of the asset pool, and the breach of loyalty (or fiduciary) duties. Chapter VIII rather refers to the liability of the originator as a result of such information and statements, but also as a result of inadequate and reckless originating or servicing practices. Chapter IX finally focuses on third parties entrusted with the soundness of the transaction towards the market, the so-called gatekeepers. In this respect, we make special emphasis on the liability of indenture trustees, underwriters and rating agencies. Chapters X and XI focus on the international aspects of securitization. Chapter X contains a conflicts of laws analysis of the different aspects of structured finance. In this respect, a study is made of the laws applicable to the vehicle, to the transfer of risks (either by assignment or by means of derivatives contracts), to liability issues; and a study is also made of the competent jurisdiction (and applicable law) in bankruptcy cases; as well as in cases where a substance-over-form is performed. Then, special attention is also devoted to the role of financial and securities regulations; as well as to their territorial limits, and extraterritoriality problems involved. Chapter XI supplements the prior Chapter, for it analyzes the limits to the States’ exercise of regulatory power by the personal and “market” freedoms included in the US Constitution or the EU Treaties. A reference is also made to the (still insufficient) rules from the WTO Framework, and their significance to the States’ recognition and regulation of securitization transactions.
Resumo:
Nell’alveo delle indagini sulla storia del commercio librario nell’Italia del Settecento, attente a individuare i legami fra circolazione del libro, diffusione delle idee illuministe e riforme politiche nella seconda metà del secolo, la ricerca ha l’obiettivo di offrire un quadro articolato della fisionomia di un mercante del libro attivo nel periodo più intenso del riformismo estense nel ducato di Modena: Moïsè Beniamino Foà (1730-1821). Il primo capitolo della tesi riguarda le cariche ufficiali che questi ricoprì al servizio delle istituzioni culturali promosse da Francesco III d’Este, le vicende che lo implicarono nelle maglie della censura e il suo impegno civile e politico a favore dei processi di emancipazione degli ebrei in età giacobina e napoleonica. Il secondo tenta di interpretare la genesi della sua fortuna economica attraverso l’esame del testamento e dell’inventario dell’asse ereditario: nel panorama di precarietà dei mestieri del libro dal secolo dei lumi ai primi decenni della Restaurazione, pare arduo individuare un libraio comparabile a Foà per solidità e capacità di investimento. All’analisi della clientela del mercante è dedicato il terzo capitolo, che si sviluppa seguendo il filo dei rapporti diplomatici intessuti da Francesco III con le corti italiane nell’orbita dell’influenza politica e culturale asburgica. Si descrivono, quindi, i viaggi europei e la rete dei contatti commerciali che garantirono la ricchezza dell’offerta rispecchiata dai numerosi cataloghi librari pubblicati nel corso di oltre un cinquantennio. Di questi si offre una descrizione bibliografica e quantitativa con un affondo sulla diffusione del libro scientifico. Con la fisionomia del mercante viaggiatore, Foà coniugava quella dell’erudito bibliofilo: la ricerca si conclude con la presentazione della sua biblioteca e dei suoi rapporti con i filologi dell’epoca.
Resumo:
La presente ricerca affronta lo studio della formazione delle realtà urbane nell'area dell'antico Ager Gallicus, grossomodo corrispondente all'attuale territorio delle Marche settentrionali. Nel quadro della colonizzazione romana il fenomeno urbano rappresenta, infatti, l'elemento cardine nell'organizzazione di un territorio. Per tale ragione, si è scelto di condurre un lavoro finalizzato alla comprensione dei tempi e dei modi che portarono alla formazione dei municipi e delle colonie nella strutturazione romana del territorio, cercando anche di comprendere le scelte insediative alla base delle singole forme strutturali. L'analisi della genesi e dello sviluppo del fenomeno urbano nell'ager Gallicus ha come obiettivo ultimo l'approfondimento della conoscenza sulla colonizzazione e romanizzazione in area medio adriatica. La ricerca si articola in: uno stato dell'arte delle più recenti interpretazioni storiografiche; una sintesi sulle cosiddette “forme della conquista” (frequentazioni “precoloniali”, realtà santuariali, fondazioni coloniarie, realtà proto-urbane legate all'agro); una dettagliata e aggiornata schedatura storico-archeologica e urbanistico-topografica delle singole realtà urbane dell'ager Gallicus (le colonie di Sena Gallica, Pisaurum, Fanum Fortunae e Aesis, e i municipi di Forum Sempronii, Suasa e Ostra, e Sentinum); una parte conclusiva dove, mettendo a confronto gli elementi alla base della definizione urbana delle realtà esaminate, vengono delineati e sintetizzati i principali modelli di formazione delle città nell'ager Gallicus così individuati (fondazione coloniaria; fondazione coloniaria preceduta da una fase precoloniale nella forma di conciliabulum; nucleo di aggregazione precedente (conciliabulum) scelto quale polo di riferimento del popolamento sparso nel territorio al momento delle distribuzioni viritane; centro di servizio creato in funzione di assegnazioni di terre ai coloni). Infine, viene tracciato un quadro complessivo della romanizzazione dell'ager Gallicus, che, in estrema sintesi, si configura come un processo progressivo di occupazione del territorio rispecchiato dallo sviluppo stesso del fenomeno urbano, ma che si differenzia dalle aree limitrofe o dall'area cisalpina per alcune importanti dinamiche etnico-demografiche.
Resumo:
The study of polymorphism has an important role in several fields of materials science, because structural differences lead to different physico-chemical properties of the system. This PhD work was dedicated to the investigation of polymorphism in Indigo, Thioindigo and Quinacridone, as case studies among the organic pigments employed as semiconductors, and in Paracetamol, Phenytoin and Nabumetone, chosen among some commonly used API. The aim of the research was to improve the understanding on the structures of bulk crystals and thin films, adopting Raman spectroscopy as the method of choice, while resorting to other experimental techniques to complement the gathered information. Different crystalline polymorphs, in fact, may be conveniently distinguished by their Raman spectra in the region of the lattice phonons (10-150 cm-1), the frequencies of which, probing the inter-molecular interactions, are very sensitive to even slight modifications in the molecular packing. In particular, we have used Confocal Raman Microscopy, which is a powerful, yet simple, technique for the investigation of crystal polymorphism in organic and inorganic materials, being capable of monitoring physical modifications, chemical transformations and phase inhomogeneities in crystal domains at the micrometre scale. In this way, we have investigated bulk crystals and thin film samples obtained with a variety of crystal growth and deposition techniques. Pure polymorphs and samples with phase mixing were found and fully characterized. Raman spectroscopy was complemented mainly by XRD measurements for bulk crystals and by AFM, GIXD and TEM for thin films. Structures and phonons of the investigated polymorphs were computed by DFT methods, and the comparison between theoretical and experimental results was used to assess the relative stability of the polymorphs and to assist the spectroscopic investigation. The Raman measurements were thus found to be able to clarify ambiguities in the phase assignments which otherwise the other methods were unable to solve.