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Genetica Umana e Tutela dei Diritti: la Dimensione Relazionale dell'Autonomia del Singolo
Get PDFTutelare i diritti nell'ambito della genetica umana è compito reso particolarmente complesso da alcune caratteristiche peculiari di questa scienza che, oltre a giocare un ruolo rilevante all'interno di ambiti fra loro molto diversi, ha permesso a medici e ricercatori di avere accesso ad una straordinaria mole di dati, difficilmente inquadrabili all'interno di una categoria unitaria ed omogenea. La sostanziale impossibilità di un approccio olistico alla materia ha determinato la scelta di individuare un filone tematico e di valutarne l'impatto, all'interno di due specifici contesti, permettendo così di testare la capacità degli strumenti giuridici tradizionali
di proteggere gli interessi (vecchi e nuovi) che emergano come rilevanti.
La scelta è caduta sulla particolare natura condivisa delle informazioni genetiche che, se da un lato, esaltano e conferiscono concretezza all'unicità e all'irripetibilità di ogni singolo essere umano, evidenziano, dall'altro, una complessa rete relazionale all'interno della quale questi si colloca.
In particolare, nell'ambito medico sanitario tale caratteristica impone un contemperamento fra interessi potenzialmente contrapposti. Come emerso dall'analisi comparatistica svolta, il diritto, nel tentativo di costruzione di idonei bilanciamenti, si trova a dover mettere in discussione, almeno in parte, la propria
matrice individualistica e a dover considerare, in termini relazionali, altre posizioni rilevanti, siano esse quelle di familiari che potrebbero vedere il proprio diritto alla
salute salvaguardato mediante la comunicazione di un'informazione sanitaria ottenuta da un consanguineo, quelle di un gruppo specifico investito dai risultati di
una particolare ricerca o, in un'ottica più ampia, quelle della collettività e delle generazioni future, detentrici di un interesse al progresso scientifico.
Lo stesso principio del consenso, epitome della tradizione individualistica e mezzo principe per la realizzazione di una piena autonomia in questi ambiti, è messo in crisi
dal contesto di connessioni derivato dalle informazioni genetiche e manifesta tutte le debolezze che gli derivano dall'essersi reso interprete, di recente, di un approccio
meramente difensivo. Una rilettura di tale strumento che consenta la considerazione di una dimensione relazionale appare, in definitiva, la soluzione migliore per tutelare
non solo gli interessi terzi, ma anche quelli dell'individuo stesso
Effects of rigid stems on sediment transport
No full textThe vegetation is an important factor of quality of the river ecosystem, given its capability to contribute to the chemical, biological and physical quality of water. On the other hand, the presence of vegetation in riverbed modifies flow structure, flow resistance, sediment transport and morphology. Each single modification has been largely studied, but the knowledge on the mutual relationships are still limited.
This project faces a part of these still-unknown aspects by considering the case of rigid and emergent vegetation and the relationships with sediment transport, flow field, flow resistance and bed forms at small scale. The thesis is based on experimental approach coupled with theoretical analysis. In particular, the research contributes with a rational approach (ballistic approach) to the formulation of sediment transport capacity of a vegetated riverbed as a function of hydrodynamic conditions, types of sediments, dimension and distribution of plants. The validity of the ballistic approach is proved by the comparison with a large number of experimental results obtained in a laboratory channel, in which the vegetation was modeled with cylindrical and rigid elements. The experimental results were carried out for different flow conditions, arrangement of cylinders and cylinder dimensions. For the tests, three different sediments were used, at different densities and grain sizes. The comparison allows the determination of some empirical parameters related with the velocity of movement of particles, characteristics of sediments and plants incumbrance.
A partially rational approach for the determination of the empirical parameters comes from the analysis of the flow field through the cylinders. The experimental data highlight bed areas in which the contribution to the sediment discharge is smaller, and bed areas in which is larger, with respect to an unvegetated riverbed at the same flow conditions.
The flow field analysis shows also the physical mechanisms which rule the formation of bed forms induced by plants. Height and length of vegetation bed forms are measured and related with the density of vegetation, with the plant diameters and with the average distance between the cylinders interaxis. In particular, the experimental data show the linearity between length of bed forms and average
distance between stems.
Finally, measurements of the drag force exerted by the cylinders to the flow were carried out by means a load cell fixed to the cylinders in staggered configuration. The measurements were done in a channel with fixed bed, both plane and with bed forms. The experimental measurements of drag show that the drag coefficient depends on the density of vegetation and on the presence of bed forms. This dependence is confirmed by comparing the indirect measurements of the drag coefficient with the measurements done with the load cell and fixed bed. The indirect measurements were done in the flume with mobile bed and sediment transport, for both the staggered and random distribution of cylinders.
The direct measurements in the different experimental setup and the comparison between direct and indirect measurements put in evidence that the vegetation bed forms give a contribution to global resistance that, in particular cases, is comparable with the contribution due to the rigid stems, demonstrating that to consider negligible their effect can be sometimes a rough approximation
Cross-Lingual Textual Entailment and Applications
No full textTextual Entailment (TE) has been proposed as a generic framework for modeling language variability. The great potential of integrating (monolingual) TE recognition components into NLP architectures has been reported in several areas, such as question answering, information retrieval, information extraction and document summarization. Mainly due to the absence of cross-lingual TE (CLTE) recognition components, similar improvements have not yet been achieved in any corresponding cross-lingual application.
In this thesis, we propose and investigate Cross-Lingual Textual Entailment (CLTE) as a semantic relation between two text portions in dierent languages. We present dierent practical solutions to approach this problem
by i) bringing CLTE back to the monolingual scenario, translating the two texts into the same language; and ii) integrating machine translation and TE algorithms and techniques. We argue that CLTE can be a core tech-
nology for several cross-lingual NLP applications and tasks. Experiments on dierent datasets and two interesting cross-lingual NLP applications, namely content synchronization and machine translation evaluation, conrm the eectiveness of our approaches leading to successful results. As a complement to the research in the algorithmic side, we successfully explored the creation of cross-lingual textual entailment corpora by means of
crowdsourcing, as a cheap and replicable data collection methodology that minimizes the manual work done by expert annotators
Structural Mapping between Natural Language Questions and SQL Queries
No full textA core problem in data mining is to retrieve data in an easy and human friendly way. Automatically translating natural language questions into SQL queries would allow for the design of effective and useful database systems from a user viewpoint.
In this thesis, we approach such problem by carrying out a mapping between natural language (NL) and SQL syntactic structures. The mapping is automatically derived by applying machine learning algorithms. In particular, we generate a dataset of pairs of NL questions and SQL queries represented by means of their syntactic trees automatically derived by their respective syntactic parsers. Then, we train a classifier for detecting correct and incorrect pairs of questions and queries using kernel methods along with Support Vector Machines.
Experimental results on two different datasets show that our approach is viable to select the correct SQL query for a given natural language questions in two target domains.
Given that preliminary results were encouraging we implemented an SQL query generator that creates the set of candidate SQL queries which we rerank with a SVM-ranker based on tree kernels.
In particular we exploit linguistic dependencies in the natural language question and the database metadata to build a set of plausible SELECT, WHERE and FROM clauses enriched with meaningful joins. Then, we combine all the clauses to get the set of all possible SQL queries, producing candidate queries to answer the question. This approach can be recursively applied to deal with complex questions, requiring nested sub-queries.
We sort the candidates in terms of scores of correctness using a weighting scheme applied to the query generation rules.
Then, we use a SVM ranker trained with structural kernels to reorder the list of question and query pairs, where both members are again represented as syntactic trees.
The f-measure of our model on standard benchmarks is in line with the best models (85% on the first question), which use external and expensive hand-crafted resources such as the semantic interpretation. Moreover, we can provide a set of candidate answers with a Recall of the answer of about 92% and 96% on the first 2 and 5 candidates, respectively.
Studio della relazione genitore - bambino in soggetti con Disturbo dello Spettro Autistico
Get PDFIl presente lavoro ha lo scopo di studiare in dettaglio l’interazione genitore-bambino in famiglie con bambini con Disturbo dello Spettro Autistico (che verranno sintetizzati con l’acronimo ASD dalla definizione inglese “Autism Spectrum Disorder”). I disturbi dello spettro autistico sono disordini del neurosviluppo che alterando nei primi anni di vita la capacità di mettersi in relazione con gli altri, determinano gravi effetti cognitivi, affettivi e comportamentali. Le ricerche condotte negli ultimi decenni nell'ambito della psicologia dello sviluppo hanno evidenziato il ruolo centrale delle relazioni genitoriali nello sviluppo del bambino, sia in bambini con sviluppo tipico che con sviluppo atipico. Questo lavoro di tesi ha l’obiettivo di osservare alcuni aspetti peculiari dell’interazione genitore-bambino in bambini con disturbo dello spettro autistico, considerando come il deficit a livello del “cervello sociale” si ripercuote sullo strutturarsi e il mantenersi di questa relazione. Nel presente lavoro si collocano quattro studi. In particolar modo saranno analizzate nel primo studio le caratteristiche del gioco in diadi madre-bambino con ASD confrontandole con diadi madre-bambino in cui il bambino presenta la Sindrome di Down o lo sviluppo tipico al fine di evidenziare similitudini e differenze sia nelle abilità manifestate dalle madri sia per quelle espresse dai bambini. Nel secondo studio, verrà approfondito l’aspetto del gioco specificatamente in interazione madre-bambino e padre-bambino in famiglie con bambini con ASD, al fine di osservare se la capacità di gioco manifestate dal bambino si differenzino in base alla figura genitoriale con cui stanno interagendo e per evidenziare se madre e padre evidenziano delle caratteristiche peculiari in base al ruolo genitoriale rivestito. Il terzo studio, invece, si è concentrato sull’analisi dello scambio sincronico all’interno delle diadi madre-bambino con disturbo dello spettro autistico confrontandolo con interazioni con bambini con sviluppo tipico e sindrome di Down, con lo scopo di osservare più in dettaglio la struttura dello scambio diadico per evidenziare i contribuiti specifici di entrambi i membri della diade, mostrando come possano differire in base alla presenza o meno di una patologia. Infine nel quarto studio sarà osservata la disponibilità emotiva diadica all’interno di famiglie di bambini con disturbo dello spettro autistico, analizzando sia i comportamenti del bambino sia i comportanti delle due figure genitoriali
Investigating domain-general short-term memory for order versus specific item memory in developmental dyslexia
No full textRecent findings suggest that people with dyslexia experience difficulties with the learning of serial order information during the transition from short- to long-term memory. At the same time, models of short-term memory increasingly incorporate a distinction of order and item processing. This work aims to investigate whether serial order processing deficiencies in dyslexia can be traced back to a selective impairment of short-term memory for serial order, and whether this impairment also affects processing beyond the verbal domain. In three studies, dyslexic children in Italy, good and poor reading school children in Germany and a sample of adults in Belgium participated in 2 x 2 experiments in which short-term recognition performance for order and item information was assessed, using both verbal and nonverbal material. The findings indicate that, irrespective of the type of material, children and adult participants with dyslexia recalled the individual items with the same accuracy as the matched control group, whereas the ability to recognize the serial order in which those items were presented appeared to be affected in the dyslexic groups. This work concludes with the assumption that dyslexia is characterized by a selective impairment of serial order short-term memory and discusses the implications of these findings for current theoretical views on dyslexia and its associated dysfunctions
Mapping of Post-Transcriptional Regulatory Networks by Means of Mechanistic and High Throughput Data
No full textPost-transcriptional regulation of gene expression (PTR) is the process responsible for modulating mRNA levels and the related amount of protein. Initially thought to have a limited impact on cell phenotype, it has become increasingly recognized as a strong determinant of the quantitative changes in proteomes, and therefore a driving force for cell phenotypes. Untranslated regions of mRNAs (UTRs) are the core mediator of this process, containing sequence and structural elements bound by various kind of regulators, which influence nuclear export, localization, stability of mRNAs and their translation rates, as well as capping, alternative splicing and polyadenylation of the transcribed pre-mRNA.
One of the most important classes of PTR factors are the RNA-binding proteins (RBPs), whose human genome complement is at least 800 genes, characterized by the presence of different functional domains. RBPs bind to the 5’UTR of a transcript often to modulate translation initiation, and to the 3’UTR usually to influence its stability or translatability. Another major group of actors in PTR are noncoding RNAs (ncRNAs). Among them are various classes of long ncRNAs (lncRNAs), the intensively studied microRNAs (miRNAs), siRNAs (small-interfering RNAs) and several other RNA types. miRNAs bind to 3’UTRs by means of short regions of perfect sequence complementation or with some mismatches. Both RBPs and ncRNAs bind mRNAs to the so-called cis-elements, found primarily in 5’ and 3’ UTRs. These elements can be represented as recurring RNA sequences or secondary structures to which the trans factors bind to exert a control over the mRNA.
In order to integrate the available experimental data, we have developed AURA, a database offering a comprehensive view of the phenomena through regulatory data including RBP and miRNA binding sites, cis-element annotations, secondary structures, phylogenetic conservation, SNPs, RNA-editing data, gene expression profiles and more. A dynamic graphical interface allows the user to browse through the UTRs in an easy and seamless way. To further enrich this body of data, we also implemented a pipeline for the identification of hyperconserved elements in human UTRs, which we applied to both 5’ and 3’UTRs. We were thus able to recover known and novel PTR mechanisms involving RBPs, including an RBP network controlled by HuR. We are eventually applying the results of these works to infer altered, and thus potentially disease-related, PTR mechanisms in an highthroughput neuroblastoma dataset
Structural and Cultural Determinants of Fertility and Female Labour Market Participation in Italy and Europe
No full textThe thesis contributes to the explanation of two well-documented phenomena: the strong decline in fertility rates and the parallel increase in female labour market participation which occurred in the last decades in most OECD countries. The argument is studied by means of a European comparison and an in-depth analysis of the Italian case. An innovative aspect of the work is the combination of cultural and structural explanations. In fact, the main argument of the thesis is that cross-national differences and the puzzling Italian and Southern European pattern of low fertility and low female labour market participation should be understood as stemming from the interplay between different factors, related to a structural – Welfare Regimes and the Economic Theory of the Family – and a cultural theoretical framework – the Second Demographic Transition and the distinction between “strong” and “weak” family systems.
In detail, the thesis shows empirically how both women’s opportunity-costs and households’ economic resources as well as family values and preferences are useful to understand fertility and female labour market participation behaviours. ILFI (Indagine Longitudinale sulle Famiglie Italiane, 1997-2005) data have been used to demonstrate how individual- and household-level mechanisms, connected with social stratification, underlying the transition to parenthood and female labour market participation around childbirths are coherent with the Italian familialistic institutional setting. Italy is an interesting case not least because of its strong regional heterogeneity, which concerns also the family formation process. Adopting an epidemiological approach, ILFI and IARD data on the condition of youth (2004) are exploited to show how the regional heterogeneity in family behaviours within Italy, such as the lower age at parenthood and the higher fertility rates in Southern regions in the selected cohorts, may be largely explained by differences in family values. This first hint suggesting the role of culture on demographic behaviours is developed further in a comparative setting using EVS (European Values Study, 1990-2008) data. The latter allowed to assess directly the importance of values and attitudes for women’s labour market participation and fertility decisions in 15 European countries. Finally, the comparison between the different paths followed by Italy and the Netherlands in the last thirty years is discussed as an example of how changes in the institutional settings in order to foster work-family reconciliation are deeply embedded within wider processes of social change.
Based on the developed theoretical framework and the results of the mentioned empirical analyses, the author attempts to integrate different streams of the literature and presents an argumentation about the complex interplay between interests, ideas and institutions underlying fertility and female labour market participation trends and patterns
Three Case Studies For Understanding, Measuring and Using a Compound Notion of Data Quality With Emphasis on the data Staleness Dimension
No full textBy its nature, the term “data quality” with its generic meaning “fitness for use” has both subjective and objective aspects. There are numerous methodologies and techniques to evaluate its subjective parts and to measure its objective parts. However, none of them are uniform enough for exploitation in diverse real-world applications. None of those, in fact, can be created as such, since data quality penetrates too deep into business operations to prevent from finding “a silver bullet” for all of them: it normally goes from representation of real world entities or their properties with data in an information system, to data processing and delivering to consumers. In this work, we considered three real world use cases which entirely or partially cover those areas of data quality scope.
In particular, we study the following problems: 1) how quality of data can be defined and propagated to customers in a business intelligence application for quality-aware decision making; 2) how data quality can be defined, measured and used in a web-based system operating with semi-structured data from and designated to both humans and machines; 3) how a data-driven (vs. system-driven) time-related data quality notion of staleness can be defined, efficiently measured and monitored in a generic information system. Thus, we expand the corresponding state of the art with Application, System and Dimension aspects of data quality.
In the Application context, we propose a quality-aware architecture for a typical business intelligence application in a healthcare environment. We demonstrate potential quality issues implications, including intra- and inter-dimensional quality dependencies, prone to data from early processing stages up to the reporting level.
In the part dedicated to the System, we demonstrate an approach to understand, measure and disseminate data quality measurement results in a context of a web based system called Entity Name System (ENS).
On the Dimension side, we propose a definition of data staleness in accordance with key time-related quality metrics requirements, relying on the corresponding similar notions elaborated by the researchers before. We demonstrate an approach to measure data staleness by different statistical methods, including exponential smoothing. In our experiments, we compare their space efficiency and data update instants predictive accuracy using history of updates of sample representative articles from Wikipedia
On problems in homogenization and two-scale convergence
No full textThis thesis addresses two problems from the theory of periodic homogenization and the related notion of two-scale convergence. Its main focus rests on the derivation of equivalent transmission conditions for the interaction of two adjacent bodies which are connected by a thin layer of interface material being perforated by identically shaped voids. Herein, the voids recur periodically in interface direction and shall in size be of the same order as the interface thickness. Moreover, the constitutive properties of the material occupying the bodies adjacent to the interface are assumed to be described by some convex energy densities of quadratic growth. In contrast, the interface material is supposed to show "extremal" constitutive behavior. More precisely, it is assumed that the constitutive relations of the interface material are once more characterized by a convex energy density of quadratic growth which, however, scales with the inverse thickness of the interface layer. In accordance to recent works on homogeneous interfaces in an analogous constitutive setting, it is found that in the limit of vanishing interface thickness and void size the interaction of the bodies adjacent to the interface can asymptotically be described by equivalent transmission conditions on the flattened interface. These transmission conditions are such that they penalize in-plane gradients in the interface. Cell formulas defining the homogenized transmission conditions on the flattened interface are derived, using a combination of Gamma-convergence methods and suitable adaptions of the periodic unfolding method in rescaled (perforated) thin domains. Depending on whether the voids touch the periodicity cells' faces, different periodic unfolding operators can be applied. The thesis' final chapter contains the results of a recent collaboration with Stefan Neukamm on the effects on two-scale convergence caused by a translation of the coordinate frame. It is observed that given a vanishing sequence of microscale parameters, a once two-scale convergent sequence is in general no longer two-scale convergent when described in a translated coordinate frame, even though it remains two-scale convergent along suitable subsequences. Yet, all two-scale cluster points of the translated sequence are indeed revealed as translates of the original two-scale limit. In fact, these two-scale cluster points are not only translated in the macroscopic variable, but also in the microscopic variable by microtranslations which belong to a set that is determined solely by the translation of the coordinate frame and the vanishing sequence of microscale parameters. This result is then applied to a novel homogenization problem that involves two different coordinate frames and yields a limiting behavior governed by emerging microscopic translations. Finally, in addition to these results the thesis also indicates a possible extension of the periodic unfolding method to so-called non-translatory periodic microstructures