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Civility vs. incivility in online social interactions: an evolutionary approach
No full textEvidence is growing that forms of incivility–e.g. aggressive and disrespectful behaviors, harassment, hate speech and outrageous claims–are spreading in the population of social networking sites’ (SNS) users. Online social networks such as Facebook allow users to regularly interact with known and unknown others, who can behave either politely or rudely. This leads individuals not only to learn and adopt successful strategies for using the site, but also to condition their own behavior on that of others. Using a mean field approach, we define anevolutionary game framework to analyse the dynamics of civil and uncivil ways of interaction in online social networks and their consequences for collective welfare. Agents can choose to interact with others–politely or rudely–in SNS, or to opt out from online social networks to protect themselves from incivility. We find that, when the initial share of the population of polite users reaches a critical level, civility becomes generalized if its payoff increases more than that of incivility with the spreading of politeness in online interactions. Otherwise, the spreading of self-protective behaviors to cope with online incivility can lead the economyto non-socially optimal stationary states
Jonas, Hobbes e le forme della paura
No full textThis essay aims at clarifying the concept of Jonas’s heuristic of fear. Although it has been severely criticized, fear remains an aspect of his thought which has drawn little attention, particularly regarding the role it plays in the elaboration of the imperative of responsibility. Jonas elaborates a new concept of fear, moulded by the particular form of uncertainty brought about by the technological age. Although critics have interpreted Jonas’ attempt as an ethics founded on irrationality and emotion, the present analysis shows that Jonas affirms a cognitivist theory of fear. The concept of fear he discusses in The Imperative of Responsibility is not an emotion as an immediate physical and psychological reaction, but a form of evaluative thinking that is part of responsibility. In order to illustrate form and function of fear in Jonas thought, I will refer to the meanings of fear in Hobbes, an author Jonas himself refers to
Epidemiology and genetic characterization of <i>Border Disease Virus</i> circulating in Sardinia
No full textBorder Disease Virus (BDV), a pestivirus from the Flaviviridae family, is an important pathogen of sheep and goats responsible for significant losses in farms around the world. In spite of the relevance of this pathogen there are only a few epidemiological studies on BDV infection and, as a consequence, the economic impact on small ruminant productions is probably under-estimated. The aims of this study are i) to determine the distribution of BDV in small ruminant farms in Sardinia and genetically characterize circulating strains ii) analyze the relation between seroprevalence, Somatic Cells Count (SCC) an milk yeld. ELISA was performed using “BVDV/MD/BDV p80 Protein Antibody Test Kit” (IDEXX) on serum of bulk tank milk (BTM) samples collected from Sardinian sheep flocks and goat herds between spring 2014 and 2015. The number of sampled farms corresponded to 8.5% of all registered farms in Sardinia. RNA was isolated using Qiamp Viral RNA mini kit from the cellular fraction of each ELISA positive BTV sample and amplified by rt-PCR using complementary primers to a highly conserved region in the untranslated regions (UTRs) of the viral genome. The amplicons were sequenced for phylogenetic analysis. Geographic distribution of collected specimen, seroprevalence and virological positive samples were analyzed via GIS (ESRI ARCGIS 10.3). ELISA screening shows a seroprevalence of 8.3% among goat farms and 10.5% among ovine farms. Ten from the ELISA positive samples were found rt-PCR positive. The sequence analysis indicates that all the amplified samples match with BDV genomes and the phylogenetic analysis revealed that all the viruses clustered in the same group classified as BDV-7. BDV-7 is the only group isolated in Sardinia so far
A New algorithm for adapting the configuration of subcomponents in large-scale optimization with cooperative coevolution
No full textThe cooperative coevolutionary (CC) approach can be very effective in solving problems of large-scale continuous optimization (LSGO) through their decomposition into lower-dimensional subcomponents. However, it is well known that the CC performance can be significantly influenced by the adopted decomposition. Moreover, since the method may require evolving a number of populations, also the size of the latter can largely affect the optimization process. In this article, focusing on equally sized decompositions, we present the results of an in-depth investigation concerning the effects of both the size of populations and the dimensionality of subcomponents on the performance of a CC optimizer. According to our study, in several cases only a small set of suitable configurations corresponds to a high optimization performance. Furthermore, we propose a new CC algorithm in which part of the available computational budget is spent for adapting both the dimensionality of subcomponents and the number of evolved individuals during the optimization process. Using a rich set of benchmark problems, we show that the proposed approach can outperform a state-of-the art algorithm based on adaptive equally sized decompositions
A proposito della Brexit: gli effetti del referendum sul Regno Unito e l'Unione europea
Get PDFAll sorts of constitutional issues arise out of the British referendum on EU membership. How to leave the European Union; whether the new Prime Minister will seek to call a general election; whether the referendum is legally binding. The article attempts to explore these issues to illustrate some of the EU referendum dynamics. Firstly, it deals with consequences of Eu referendum for British politics. Then, it focuses on the impact of Uk referendum on the European integration process
Study of <i>Salmonella</i> pathogenicity mechanisms in <i>vitro</i> and in <i>vivo</i>
No full textSalmonella enterica subsp. enterica includes many pathogenic serovars. Models of the study are S. typhimurium and S. abortusovis, a restricted serovar to sheep.
Bacterial pathogen’s transmission strategies are usually connected to pathogenesis and limited information is available about the immune response of sheep to S. abortusovis and about flagellin interaction with S. abortusovis. Knowledge about those factors are mainly based on studies of S. typhimurium.
Here we try to understand the role of flagella in S. abortusovis. The idea is that S. abortusovis highly regulates expression of flagella within the host, and we performed studies to clarify how S. abortusovis evade activation of the immune system.
Mutations in S. abortusovis flagella genes were generated and flagella from wild type and mutant’s strains of the two different serovars were extracted using diverse media to observe differences in flagellation and host interaction. Samples were analyzed by Western Blot to determine expression of major flagellar protein. Surface expression of flagella was verified by Flow Cytometry and by Scanning Electron Microscopy. To verify the capacity of S. typhimurium and S. abortusovis to stimulate TLR5, a colorectal
carcinoma cell line (T84 cells) was treated with purified flagellin and the transcriptional induction of a CXC chemokine IL-8 was measured.
We showed that S. abortusovis flagella are expressed in specific media, and they induced the transcription of IL-8 in T84 cells
Alla ricerca delle basi molecolari del Diabete di Tipo 1: sequenziamento di ultima generazione in gemelli monozigoti concordanti e discordanti per la malattia
No full textDuring my three years of PhD, I worked on a project which aims to clarify the molecular basis of Type 1 Diabetes (T1D), an autoimmune chronic disease showing a strikingly and, when compared to other Mediterranean regions, anomalously high incidence in the isolated founder population from Sardinia.
The project, supervised by Prof. Francesco Cucca, involves the transcriptome, metilome and TCR repertoire analysis in CD4+ and CD8+ cells fromSardinian monozygotic twins (MZ), both concordant and discordant for T1D.The aim, during my PhD course, was to clarify how changes in transcriptional activity may contribute to the disease.
CD4+ and CD8+ cells were collected from 3 concordant and 2 discordant Sardinian twin pairs, andtotal RNAwas isolated. The polyadenilated fraction was then sequenced and reads were mapped to the human genome, normalized, and scaled for library size and gene length. Gene expression levels were then quantified.
Samples were sequenced with a mean coverage of ~60 millions of clusters, reads composition showed the expected behavior for PolyA(+) libraries. Nine genes were found differentially expressed between discordant MZ only in CD8+ cells.
Results needs to be validated in a larger sample and further studied to confirm and understand the putative role of the 9 genes in T1D.
The transcriptome, the metilome and TCR repertoire analysis in studies with MZ pairs concordant and discordant could contribute to the understanding of the pathogenesis of T1D
Antiviral-hyperactivation limiting therapeutics for the treatment of viral diseases and cancer
No full textCurrent anti-HIV drugs target several of viral enzymes that HIV requires to replicate and survive. Hyperactivation of the immune system is now recognized as the major driver of progression to AIDS and of the emergence of both AIDS-defining and non-AIDS events which negatively impact upon morbidity and mortality despite fully suppressive ART. AV-HALTs are a new class of antiretrovirals that both reduce HIV replication and excessive immune activation. By targeting a human rather than a viral enzyme the chances of the virus developing resistance are decreased, an improvement over traditional antiretroviral drugs. The proof of concept for this new class of drugs was achieved with a Phase IIa study in which the HU/ddI combination (first generation AV-HALTs) safely achieved the goals established for the AV-HALT class. The idea of AV-HALTs was further expanded in order to join both the antiproliferative and antiviral activities into a single molecule. CDK9 inhibitors were tested with the goal to identify second generation AV-HALTs. Compounds with good toxicity and activity profile were moved to preclinical development and were tested for ADME properties and preliminary in vivo experiments in rodent species. In addition, CDK9 inhibitors were found to be active against other viruses such as HSV-1, HSV-2, EBV and HPV. This class of compounds also proved to inhibit proliferation of tumor cells both in vitro and in vivo
La Metodologia Feuerstein nell'ambito della scuola primaria: principi e strumenti della mediazione educativa per favorire il successo scolastico
No full textThe aim of this experimental research is to examine Feuerstein’s educational theory.
By expanding on theories from Piaget and Vigotskij, Feuerstein described a method to teach students how to study through the development of an active structural approach. This is effective for learning because it develops habits for seeking novel strategies when faced with new and complex problems.
The study, after analysing the international literature on the application of the method in primary school, investigates one of the problems arising from the examination conducted so far: why isn’t the Feuerstein’s Instrumental Enrichment process consistently affects student performance in all subjects always?
The assumption of this research is that the Feuerstein program cannot influence the academic performance if it is not integrated into the school curriculum. It can be assumed that if the Feuerstein principles of mediated learning were applied to all subjects, a cognitive-curriculum can be developed, resulting in a significant improvement in the school performance.
The study consists of a two-year quasi- experiment in a primary school (2013-2014, 2014-2015):83 students in the fourth and fifth grades and 4 IE (Instrumental Enrichment) trained teachers were involved. They were divided into four independent groups: two are experimental and two are for comparison. Quantitative and qualitative assessment tools will be used before and after the process. The best results on school performance and quality of learning mediation are achieved by combining the program with the methodological criteria integrated into to the school curriculum
La Partecipazione ai processi decisionali delle persone di età minore.: una ricerca-azione sulla partecipazione alla programmazione delle politiche sociali della città di Cagliari.
No full textThis Ph.D. thesis is about the participation of people under age in decisional processes, from a juridical, sociological and social services point of view.
Bibliographic research studied the three elements subject of this observation: participation, participation and people under age and participated planning of social policies, concentrating on the regulatory, theoretical and theoretical-practical aspects.
The empirical research was carried out in a action-research form, with the aim of studying the phenomena of the participation of people under age in the making of social policies in the Municipality of Cagliari, within a setting in which the researcher, the administrators, the operators and the minors confront each other and contribute collectively to its definition and to the actions that could influence the phenomena in itself.
The research objective was to understand if it was feasible to guarantee the contribution of the minors in the planning process, to what extent, and which elements could affect the possibility of guaranteeing this participation, through institutional moments of confrontation with the political decision makers.
Fifteen associations adhered to the project and 200 people were involved, amongst which children and teenagers.
The results of the research, here reported in chapter 4 and in the conclusions, were also included in a report prepared for the Municipal Council