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Text localization and recognition in natural scene images
No full textText localization and recognition (text spotting) in natural scene images is an interesting task that finds many practical applications. Algorithms for text spotting may be used in helping visually impaired subjects during navigation in unknown environments; building autonomous driving systems that automatically avoid collisions with pedestrians or automatically identify speed limits and warn the driver about possible infractions that are being committed; and to ease or solve some tedious and repetitive data entry tasks that are still manually carried out by humans. While Optical Character Recognition (OCR) from scanned documents is a solved problem, the same cannot be said for text spotting in natural images. In fact, this latest class of images contains plenty of difficult situations that algorithms for text spotting need to deal with in order to reach acceptable recognition rates. During my PhD research I focused my studies on the development of novel systems for text localization and recognition in natural scene images. The two main works that I have presented during these three years of PhD studies are presented in this thesis: (i) in my first work I propose a hybrid system which exploits the key ideas of region-based and connected components (CC)-based text localization approaches to localize uncommon fonts and writings in natural images; (ii) in my second work I describe a novel deep-based system which exploits Convolutional Neural Networks and enhanced stable CC to achieve good text spotting results on challenging data sets. During the development of both these methods, my focus has always been on maintaining an acceptable computational complexity and a high reproducibility of the achieved results
Valutazione probabilistica della pericolosità da fagliazione superficiale: analisi del metodo per un'applicazione nel processo di localizzazione del deposito nazionale dei rifiuti radioattivi
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La fagliazione superficiale all'interno del processo per la localizzazione di un deposito di rifiuti radioattivi
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Risk assessment in centralized and decentralized online social network.
Get PDFOne of the main concerns in centralized and decentralized OSNs is related to the fact that OSNs users establish new relationships with unknown people with the result of exposing a huge amount of personal data. This can attract the variety of attackers that try to propagate malwares and malicious items in the network to misuse the personal information of users. Therefore, there have been several research studies to detect specific kinds of attacks by focusing on the topology of the graph [159, 158, 32, 148, 157]. On the other hand, there are several solutions to detect specific kinds of attackers based on the behavior of users. But, most of these approaches either focus on just the topology of the graph [159, 158] or the detection of anomalous users by exploiting supervised learning techniques [157, 47, 86, 125]. However, we have to note that the main issue of supervised learning is that they are not able to detect new attacker's behaviors, since the classifier is trained based on the known behavioral patterns. Literature also offers approaches to detect anomalous users in OSNs that use unsupervised learning approaches [150, 153, 36, 146] or a combination of supervised and unsupervised techniques [153]. But, existing attack defenses are designed to cope with just one specific type of attack. Although several solutions to detect specific kinds of attacks have been recently proposed, there is no general solution to cope with the main privacy/security attacks in OSNs.
In such a scenario, it would be very beneficial to have a solution that can cope with the main privacy/security attacks that can be perpetrated using the social network graph. Our main contribution is proposing a unique unsupervised approach that helps OSNs providers and users to have a global understanding of risky users and detect them. We believe that the core of such a solution is a mechanism able to assign a risk score to each OSNs account. Over the last three years, we have done significant research efforts in analyzing user's behavior to detect risky users included some kinds of well known attacks in centralized and decentralized online social networks.
Our research started by proposing a risk assessment approach based on the idea that the more a user behavior diverges from normal behavior, the more it should be considered risky. In our proposed approach, we monitor and analyze the combination of interaction or activity patterns and friendship patterns of users and build the risk estimation model in order to detect and identify those risky users who follow the behavioral patterns of attackers. Since, users in OSNs follow different behavioral patterns, it is not possible to define a unique standard behavioral model that fits all OSNs users' behaviors. Towards this goal, we propose a two-phase risk assessment approach by grouping users in the first phase to find similar users that share the same behavioral patterns and, then in the second phase, for each identified group, building some normal behavior models and compute for each user the level of divergency from these normal behaviors. Then, we extend this approach for Decentralized Online Social Networks (i.e., DOSNs). In the following of this approach, we propose a solution in defining a risk measure to help users in OSNs to judge their direct contacts so as to avoid friendship with malicious users. Finally, we monitor dynamically the friendship patterns of users in a large social graph over time for any anomalous changes reflecting attacker's behaviors. In this thesis, we will describe all the solutions that we proposed
Impianto valvolare aortico transcatetere (TAVI). Studio monocentrico, prospettico, osservazionale.
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‘Primum educere’. L’Obiezione di Coscienza fra gli studenti dei Corsi di Laurea in Ostetricia in Lombardia: studio osservazionale descrittivo trasversale.
Get PDFThe Italian legislation on abortion and Medically Assisted Procreation (L. 194/78 and L. 40/2004) gives the Healthcare Professionals the opportunity to exercise they right to conscientious objection, a subject of current bioethical debate. From the published literature comes out that students are in an awkward situation and they need to reflect on this issue during the course. The idea of present study emerges from the results of the analyzed literature that underlines how a certain number of medicine students refuses to learn the procedures to provoke the voluntary interruption of pregnancy and claims their right to conscientious objection, more than that, the lack of data referring to midwifery students asserts how necessary a study of this kind can be to help understand their position about the issue.
Objective
The main aim of this study is to try and explore attitudes, legal knowledge, experiences and decision-making possibilities of the students attending the third year of the Bachelor in Midwifery towards conscientious objection in the Universities of Lombardy and the possible need of further education in the field.
Method
This study is an observational study that explore attitudes, legal knowledge and experiences in midwifery student enrolled in five Universities in Lombardy. The sample of the study are the 112 undergraduates of the Bachelor in Midwifery that give their consent to take part in the survey. The enrollment and the data collection happened between September and October 2015. A structured, anonymous questionnaire was used for the survey and it includes 37 closed questions in four sections, and three open questions. It has been distributed to the students by the study team. Of the 112 questionnaires, 111 were returned.
Results
From the study emerges the students have acquired the knowledge of the legislation related the conscientious objection and related laws, with a frequency of 62.9% correct answers.
Analyzing the data comes to light that the students think that the time devoted to teaching conscientious objection and protection of motherhood within the curriculum is not enough and only 51% say that the student has sufficient information on the procedures concerning the conscientious objection. The study shows that the majority of the midwifery students do not know that the law does not mention them among the ones with the right to conscientious objection. On the other hand, the last open answer show that some of them do not know if they have the right to express their attitude during their training. Nevertheless, 88% believe that students have the right to act according to their conscience highlighting their conscientious objection while they are carrying out the study program, even though the sample considers important the achievement of their target training and their claim on moral values, as long as the university recognized a method of achieving that objective which does not require than to perform practices that directly conflict with their own moral values.
The sample was asked if they thought the knowledge of legislation was sufficient to solve ethical position related to situations that could cause conscientious objection: 42 students out of 60 declared to think the knowledge of legislation a necessary but insufficient element to face and solve the answer to conscientious objection.
Conclusion
Even though the students have a global knowledge of the legislation, a deeper and wider general knowledge of the laws in question could be a safeguard both for students and women and more than that it could ensure the provision of the highest standard of care. During the three years of the Bachelor in Midwifery, starting from the first one, more time should be dedicated to the discussion of cases and the analysis of conflicting values. A proposal for the Schools of Medicine could be the creation of a specific form for the conscientious objection, to be filled in by the students who feel the need to make their position official but, first of all, the institution has to create a partnership with its students that guarantees the right of each student to be respected for his own moral values and to be led to an informed, conscious and shared choice over the conscientious objection, via a more adequate training, which can prevent the distress generated when students are not put in the position to be able to face conscientious objection
Development and optimization of the production process of a recombinant human protein by high-throughput techniques. Sviluppo e ottimizzazione del processo di produzione di una proteina umana ricombinante attraverso l'utilizzo di tecniche high-throughput.
Get PDFMost biotechnology unit operations are complex with numerous process variables, feed material and raw material attributes that play significant impact on the performance of a process. Design of Experiment (DoE)-based approach together with HTPD (High-Throughput Process Development) techniques offer a solution to this issue allowing for an efficient estimation of effects and interactions by employing a minimal number of experiments. In the first part of the PhD work the HTPD approaches combined to statistical software were adopted in order to optimize a production process of a 340 kDa therapeutic recombinant protein expressed in PER.C6 cell line. The optimization of the purification process was performed by increasing the yield and by reducing the HCPs, residual DNA and viral contamination in order to obtain a fully compliant GMP process. This was achieved by introducing an arginine washing step during the capture on AEX resin and by reducing the concentration of phosphate in elution buffer in the intermediate step on hydroxyapatite, preventing the co-elution of the protein of interest and rDNA. A decrease of rDNA was then obtained by a membrane AEX step (by flow-through mode). Finally, two viral reduction steps (by thermal inactivation and filtration) were used in order to satisfy ICH Q5A guidelines.
In the second part of the work, the DoE and HTPD technology were used as a “tool box” inside a step by step “decision tree” in order to lead the experimenter in a well defined path with the purpose of purifying and formulate any protein of interest. The protein used to test the procedure was a 13 kDa protein expressed in E. coli as inclusion bodies. The novel process allowed to obtain a pure and active preparation of the protein compliant to GMP requirements
Production and characterization of novel lignin-modifying enzymes from actinomycetes and heterologous expression of metagenome-source laccases. Produzione e caratterizzazione di enzimi ligninolitici in attinomiceti e espressione eterologa di laccasi da metagenoma.
Get PDFThe lignin is a recalcitrant aromatic biopolymer and its bio-degradation occurs by white rot fungi through the production of an enzyme array such as lignin, manganese and versatile peroxidases and laccases. The aims of this PhD project were the production and characterization of novel lignin-degrading enzymes from actinomycetes and the heterologous expression of a metagenome-sourced laccase. The classical approach of screening applied to microbial isolates led to the discovery of a novel peroxidase activity produced by Nonomuraea gerenzanensis.
This peroxidase showed features such as high alkaline pH, thermo stability and decolorization of industrial dyes that favorably compare with the ones of fungal peroxidases. A possible application for this peroxidase might be in textile and decontamination meal of environmental pollutants. The metagenome-based approach allows to overcome cultivation-dependent limitations, directly analyzing genomes’ potential in environmental samples. This approach led to the discovery of a novel bacterial laccase (MetaLacc) affiliated to phylum Acidobacteria. MetaLacc shows ability to oxide a variety of phenolic substrates in a wide range of pHs, high tolerance towards salts, increased activity in the presence of alcohols and decolorization of industrial dyes. A possible application for Metalac might be as well in the treatment industrial wastewater. Finally, N. gerenzanensis and Streptomyces coelicolor A3 (2) were analyzed to degrade wheat straw or/and lignin in a two-stage bioconversion process. The first stage is the enzymatic digestion of pre-treated wheat straw by the two selected aerobic microorganisms. A second stage of anaerobic fermentation to produce biofuels will eventually follow
Effects of dopaminergic pathways on human neutrophil
Get PDFThe existence of a bidirectional communication between the immune system and the central nervous system was postulated some years ago by different researchers. More recently some evidence supports the notion that immune system can be affected by dopamine (DA).
DA is a neurotransmitter of the central nervous system that exerts its effects through the activation of the five dopaminergic receptors (DR). DA can affect some functions of the cells of the immune system and this topic was widely investigated on the cells of adaptive immunity.
Therefore, we decided to focus our attention on the different cell populations of the innate immunity and to explore the data present in literature about the evidence of the existence of a dopaminergic regulation of these cells.
The first part of the thesis is a description of dopamine and of the dopaminergic system, with reference to interactions with the immune system, in particular the innate immunity. Moreover, in the last part of this first chapter are mentioned some diseases involving the innate immunity in which the role of dopaminergic pathway was postulated and in some case demonstrated.
The second chapter is devoted to the characterization from the physiological point of view of the other major actors of the work, neutrophils (PMN). Also in this case, at the end of the chapter there is a section dedicated to the relevance of PMN in diseases in which the immune component is relevant.
The third chapter represents the main results of my PhD project, based on the investigation of the role and relevance of the dopaminergic system in human neutrophils. The aim of this PhD research program was in fact, to characterize the presence of DR and if dopaminergic agent can affect some pivotal function of neutrophil in a receptor-dependent manner.
Finally, a last chapter resumed the other projects that I have followed during the three year of my PhD course. The two attached files represent the results of some of them, that were conclude and published
