Strichartz Type Estimates for Oscillatory Problems for Semilinear Wave Equation

The author is partially supported by: M. U. R. S. T. Prog. Nazionale “Problemi e Metodi nella Teoria delle Equazioni Iperboliche”.We treat the oscillatory problem for semilinear wave equation. The oscillatory initial data are of the type u(0, x) = h(x) + ε^(σ+1) * e^(il(x)/ε) * b0 (ε, x) ∂t u(0, x) = ε^σ * e^(il(x)/ε) * b1(ε, x). By using suitable variants of Strichartz estimate we extend the results from [6] on a priori estimates of the approximations of geometric optics.The main improvement is the fact that we can obtain a priori estimates for the case σ = 1, while in [6] we could treat only the case σ > n/2 − 1

How many cyberbullying(s)? A non-unitary perspective for offensive online behaviours

Research has usually considered cyberbullying as a unitary phenomenon. Thus, it has been neglected to explore whether the specific online aggressive behaviours relate differentially to demographic features of the perpetrators of online aggressive actions, their personality characteristics, or to the ways in which they interact with the Internet. To bridge this gap, a study was conducted through a questionnaire administered online to 1228 Italian high-school students (Female: 61.1%; 14-15 yo: 48.%; 16-17 yo: 29.1%; 18-20 yo: 20.4%, 21-25 yo: 1.6%; Northern Italy: 4.1%; Central Italy: 59.2%; Southern Italy: 36.4%). The questionnaire, in addition to items about the use of social media, mechanisms of Moral Disengagement and personality characteristics of the participants in the study, also included a scale for the measurement of cyberbullying through the reference to six aggressive behaviours. The results indicate that cyberbullying can be considered as a non-unitary phenomenon in which the different aggressive behaviours can be related to different individual characteristics such as gender, personality traits and the different ways of interacting with social media. Moreover, the existence of two components of cyberbullying has been highlighted, one related to virtual offensive actions directly aimed at a victim, the other to indirect actions, more likely conducted involving bystanders. These findings open important perspectives for understanding, preventing, and mitigating cyberbullying among adolescents

Analysis of Amphetamine and Congeners in Illicit Samples by Liquid Chromatography and Capillary Electrophoresis

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Attitudes towards cyber risks - Implicit & self-report measures. The Happy Onlife edutainment experience of secondary school children

The Happy Onlife experience has contributed to children’s right to be heard in matters affecting them in their digital interactions and lives. Happy Onlife has been considered as effective awareness raising and learning tool regarding cyber security issues by its end-users, namely students, teachers, parents and educators. By playing with Happy Onlife game, children could naturally self-disclose and express their emotions, needs, understanding and sometimes worries and doubts. Indeed, self-reporting provides valuable insights for a wide range of research, policy and educational questions, however it can be susceptible to self-presentation and socially desirable responding. To overcome these limitations, implicit measures were considered to complement experimental research about children’s attitude towards cyber risks. The work described in this document aims at evaluating the effect of the Happy Onlife tool on attitudes towards cyber risk of children aged 10-12, from Time T1 to Time T2, before and after using Happy Onlife edutainment. The first research aim is to test the Happy Onlife edutainment reliability as a learning tool for enhancing digital competences with a focus on cyber security, data protection, privacy, online communication, netiquette and digital identity management. Moreover, a second purpose is the contribution to the development and validation of a new implicit measure of cyber risk propensity for children (10-12 years old). A third aim is to investigate the relationship between implicit risk attitudes and explicit risk-taking behaviour. In this pilot research all explicit and implicit measures showed adequate reliability. There was a significant effect pre and post Happy Onlife gaming experience. Current results suggest that the Cyber Security Implicit Association Test (IAT) is a reliable and valid method and may be a useful tool to be added to self-report batteries for cyber risk propensity assessment in children. The Cyber Security Implicit Association Test could be considered for future and wider research on risk-taking behaviour by citizens of all ages. The experiment protocol can be improved, however this contribution could be taken into consideration for the study and implementation of European cyber security strategies and policies to limit online threats and risks.JRC.E.3-Cyber and Digital Citizens' Securit

Phenotypic and genotypic characterization of Stenotrophomonas maltophilia isolates from patients with cystic fibrosis: Genome diversity, biofilm formation, and virulence

<p>Abstract</p> <p>Background</p> <p><it>Stenotrophomonas maltophilia </it>is emerging as one of the most frequently found bacteria in cystic fibrosis (CF) patients. In the present study, phenotypic and genotypic traits of a set of 98 isolates of <it>S. maltophilia </it>obtained from clinical (CF and non-CF patients) and environmental sources were comparatively evaluated.</p> <p>Results</p> <p><it>S. maltophilia </it>exhibited a high level of genomic diversity in both CF and non-CF group, thus possibly allowing this bacterium to expand its pathogenic potentials. Strains sharing the same pulsotype infected different patients, thus likely indicating the occurrence of clonal spread or acquisition by a common source. CF isolates differed greatly in some phenotypic traits among each other and also when compared with non-CF isolates, demonstrating increased mean generation time and susceptibility to oxidative stress, but reduced ability in forming biofilm. Furthermore, in CF isolates flagella- and type IV pili-based motilities were critical for biofilm development, although not required for its initiation. Sequential isogenic strains isolated from the same CF patient displayed heterogeneity in biofilm and other phenotypic traits during the course of chronic infection. CF and non-CF isolates showed comparable virulence in a mouse model of lung infection.</p> <p>Conclusions</p> <p>Overall, the phenotypic differences observed between CF and non-CF isolates may imply different selective conditions and persistence (adaptation) mechanisms in a hostile and heterogeneous environment such as CF lung. Molecular elucidation of these mechanisms will be essential to better understand the selective adaptation in CF airways in order to design improved strategies useful to counteract and eradicate <it>S. maltophilia </it>infection.</p

Circulating miR-320b and miR-483-5p levels are associated with COVID-19 in-hospital mortality

none28noThe stratification of mortality risk in COVID-19 patients remains extremely challenging for physicians, especially in older patients. Innovative minimally invasive molecular biomarkers are needed to improve the prediction of mortality risk and better customize patient management. In this study, aimed at identifying circulating miRNAs associated with the risk of COVID-19 in-hospital mortality, we analyzed serum samples of 12 COVID-19 patients by small RNA-seq and validated the findings in an independent cohort of 116 COVID-19 patients by qRT-PCR. Thirty-four significantly deregulated miRNAs, 25 downregulated and 9 upregulated in deceased COVID-19 patients compared to survivors, were identified in the discovery cohort. Based on the highest fold-changes and on the highest expression levels, 5 of these 34 miRNAs were selected for the analysis in the validation cohort. MiR-320b and miR-483-5p were confirmed to be significantly hyper-expressed in deceased patients compared to survived ones. Kaplan-Meier and Cox regression models, adjusted for relevant confounders, confirmed that patients with the 20% highest miR-320b and miR-483-5p serum levels had three-fold increased risk to die during in-hospital stay for COVID-19. In conclusion, high levels of circulating miR-320b and miR-483-5p can be useful as minimally invasive biomarkers to stratify older COVID-19 patients with an increased risk of in-hospital mortality.restrictedGiuliani, Angelica; Matacchione, Giulia; Ramini, Deborah; Di Rosa, Mirko; Bonfigli, Anna Rita; Sabbatinelli, Jacopo; Monsurrò, Vladia; Recchioni, Rina; Marcheselli, Fiorella; Marchegiani, Francesca; Piacenza, Francesco; Cardelli, Maurizio; Galeazzi, Roberta; Pomponio, Giovanni; Ferrarini, Alessia; Gabrielli, Armando; Baroni, Silvia Svegliati; Moretti, Marco; Sarzani, Riccardo; Giordano, Piero; Cherubini, Antonio; Corsonello, Andrea; Antonicelli, Roberto; Procopio, Antonio Domenico; Ferracin, Manuela; Bonafè, Massimiliano; Lattanzio, Fabrizia; Olivieri, FabiolaGiuliani, Angelica; Matacchione, Giulia; Ramini, Deborah; Di Rosa, Mirko; Bonfigli, Anna Rita; Sabbatinelli, Jacopo; Monsurrò, Vladia; Recchioni, Rina; Marcheselli, Fiorella; Marchegiani, Francesca; Piacenza, Francesco; Cardelli, Maurizio; Galeazzi, Roberta; Pomponio, Giovanni; Ferrarini, Alessia; Gabrielli, Armando; Baroni, Silvia Svegliati; Moretti, Marco; Sarzani, Riccardo; Giordano, Piero; Cherubini, Antonio; Corsonello, Andrea; Antonicelli, Roberto; Procopio, Antonio Domenico; Ferracin, Manuela; Bonafè, Massimiliano; Lattanzio, Fabrizia; Olivieri, Fabiol