DAU - Digital Archive of URL (Ramon Llull University)
Not a member yet
5388 research outputs found
Sort by
Measurement of CP violation in B0→ D+D− and Bs0→Ds+Ds− decays
Get PDFA time-dependent, flavour-tagged measurement of CP violation is performed with B0→ D+D− and Bs0→Ds+Ds− decays, using data collected by the LHCb detector in proton-proton collisions at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 6 fb−1. In B0→ D+D− decays the CP-violation parameters are measured to be (Formula presented.) In Bs0→Ds+Ds− decays the CP-violating parameter formulation in terms of ϕs and |λ| results in (Formula presented.) These results represent the most precise single measurement of the CP-violation parameters in their respective channels. For the first time in a single measurement, CP symmetry is observed to be violated in B0→ D+D− decays with a significance exceeding six standard deviations.info:eu-repo/semantics/publishedVersio
Applying 8-foci imaging to instantaneous three-dimensional flow field reconstruction
Get PDFAdvances in microfluidics have enabled the exploration of complex fluid dynamics within intricate geometries, facilitating both the fabrication of sophisticated microchannels and the study of realistic three-dimensional (3D) flow environments. However, capturing 3D flow fields with high spatial and temporal resolution still remains a significant challenge due to the limitations of current experimental techniques. Here, we introduce a novel approach using widefield multifocus microscopy to achieve instantaneous 3D flow reconstruction by simultaneously imaging eight axial planes. This technique was applied to investigate particle dynamics in microchannels engineered to replicate vascular bifurcations. In cylindrical channels mimicking blood vessels, we observed radial particle migration toward the channel center, reminiscent of margination in blood flow. At bifurcation points, particle collisions and deceleration were localized at the apex, followed by redistribution into downstream branches. Our 3D imaging further revealed complex transport phenomena, including non-Gaussian lateral displacements, Lévy flight–like behavior, and net migration away from channel walls. These findings underscore the importance of true volumetric flow measurements for elucidating particle–wall interactions and the behavior of biological fluids in both physiological and engineered 3D microenvironments.info:eu-repo/semantics/publishedVersio
Improved measurement of η/η′ mixing in Bs0→J/ψη′ decays
Get PDFBranching fraction ratios between the decays Bs0→J/ψη′ are measured using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb−1. The measured ratios of these branching fractions are (Formula presented.) where the uncertainties are statistical, systematic and related to the precision of the η(′) branching fractions, respectively. They are used to constrain the η/η′ mixing angle, ϕP, and to probe the presence of a possible glueball component in the η′ meson, described by the gluonic mixing angle ϕG. The obtained results are (Formula presented.) where the uncertainties are statistically dominated. While the value of ϕP is compatible with existing experimental determinations and theoretical calculations, the angle ϕG differs from zero by more than four standard deviations, which points to a substantial glueball component in the η′ meson and/or unexpectedly large contributions from gluon-mediated processes in these decays. The absolute branching fractions are also measured relative to that of the well-established Bs0→J/ψϕ decay, which serves as the normalisation channel. These results supersede the previous LHCb measurements and are the most precise to date.info:eu-repo/semantics/publishedVersio
Study of Λb0 and Ξb0 Decays to Λh+h′- and Evidence for CP Violation in Λb0 → Λk+K- Decays
No full textA study of Λb0 and Ξb0 decays to Λh+h′- (h(′)=π,K) is performed using pp collision data collected by the LHCb experiment during LHC Runs 1-2, corresponding to an integrated luminosity of 9 fb-1. The branching fractions for these decays are measured using the Λb0→Λc+(→Λπ+)π- decay as a control channel. The decays Λb0→Λπ+π- and Ξb0→ΛK-π+ are observed for the first time. For decay modes with sufficient signal yields, CP asymmetries are measured in the full and localized regions of the final-state phase space. Evidence is found for CP violation in the Λb0→ΛK+K- decay, interpreted as originating primarily from an asymmetric Λb0→N∗+K- decay amplitude. The measured CP asymmetries for other decays are compatible with zero.info:eu-repo/semantics/publishedVersio
In search of the silver-lining
Get PDFTensions between police organizations and (community) stakeholders have taken center stage in recent years, with an escalation in protests and divisive rhetoric observed in many countries. Using attribution theory, this study examines how police officers interpret negative stakeholder feedback and how these interpretations shape their behavioral responses. Qualitative analysis based on 148 interviews with European police officers shows that officers make six different attributions about the causes of stakeholder critique, and that these have direct implications for their behavioral responses. In particular, these different attribution patterns are found to play a critical and hitherto unrecognized role in shaping police-stakeholder relations and organizational learning among police forces.info:eu-repo/semantics/publishedVersio
Healthcare students' exposure to sexual violence during clinical placements in Spain: A cross-sectional study
Get PDFData from international investigations indicate that gender-based violence is a phenomenon that also occurs in the university environment. Despite the fact that clinical learning environments have been widely studied, little attention has been paid to sexual violence in the clinical placement setting of Health Sciences students. Consequently, the aim of this study was to describe situations and/or behaviours of harassment, such as assault and/or sexual abuse experienced by the students of one university in Barcelona, Spain, during their clinical placements. A cross-sectional study was conducted using an ad-hoc online questionnaire. A convenience sample was used including bachelor's degree students as subjects during their clinical placements in the second half of 2022. A total of 156 responses were collected from the students of four degrees (Nursing, Physiotherapy, Nutrition and Dietetics and Pharmacy). Of the total results collected, 74.5% (117) corresponded to women and the remaining 25.5% (40) to men. 71.3% of students reported that they had experienced one (or more) of the 25 types of conduct described in the questionnaire at some time. The behaviours of social interaction with sexual content and sexual harassment in the placement setting showed that such behaviours were mostly experienced by women on the Nursing degree. In relation to the perpetrators of such behaviours, the respondents manifested that the greatest aggressor was a patient and that most of the aggression took place in hospitalisation units, rehabilitation centres and nursing homes. It is essential that academic institutions, in collaboration with health institutions, carry out joint actions, awareness-raising, identification and interventions, with students, professionals and teams from a culture of non-violence and the eradication of sexual harassment in academic placements.info:eu-repo/semantics/publishedVersio
Video Game Structural Features Are Related to Internet Gaming Disorder and Motivations of Play: Design and Validation of the Video Game Structure Scale (VGSS)
Get PDFAquest article ha estat finançat per publicar en accés obert gràcies a l'acord entre CRUE-CSIC i Springer Nature.Structural characteristics of video games influence the development of maladaptive behavioral patterns such as Internet gaming disorder (IGD). The aim of this study was to develop and validate a tool to evaluate users’ perceptions of video game structural features. The sample was composed of 502 gamers with an average age of 23.35 years (SD = 6.89). In total, 67.3% used a personal computer, 20.7% a desktop console, 11.4% a mobile platform, and 0.6% a portable console. Multiple exploratory factor analyses were conducted to identify the optimal model. Initial evidence of reliability, construct, and external validity was found (TLI and CFI > .90, RMSEA < .06, SRMR < .08). Structural features were categorized into three primary factors: social, control, and reward. After a multiple linear regression, structural features and gaming motivations explain 19% of the variance in IGD. In conclusion, the scale demonstrates solid psychometric properties for assessing how Spanish-speaking players perceive the structural characteristics of video games and how these relate to the development of IGD.info:eu-repo/semantics/publishedVersio
Conceptual model for extending electric vehicle battery lifetime
Get PDFTo maximise the resource efficiency of electric vehicle lithium-ion batteries (LIBs), their lifetimes can be extended through cascading second- and third-life applications. Using expert input, this study establishes a conceptual model for understanding these applications’ state of health (SOH) thresholds and user requirements. Using a qualitative methodology, including focus group discussions with multistakeholder experts and policy analysis of the European battery regulatory landscape, we propose extending LIB use. Our model outlines potential second- and third-life applications aiming to maximise battery value retention. The findings highlight gaps in current European Union regulations that inadequately support battery-repurposing strategies. The conceptual model with an SOH threshold and key performance indicators serves as a foundation for researchers and industries to explore cascading battery applications, foster long-term resource efficiency and contribute to the circular economy by extending LIB lifespans through repurposing initiatives.info:eu-repo/semantics/publishedVersio
A-Place. Linking places through networked artistic practices
No full textThe aim of A-Place, a project co-funded by the Creative Europe programme, has been to create a network of places across countries and cultures, artistic forms and educational fields, involving professional and non-professional stakeholders in six European cities and beyond, through the use of digital media.
Over four years, from October 2019 to 2023, the A-Place project partners — nine organisations, including universities, community-based creative groups, and cultural agencies — designed, implemented, and evaluated a diverse range of placemaking activities aimed at strengthening the bonds between people and places, combining artistic and educational practices in multiple forms and contexts.
This online publication compiles the extensive work undertaken during the four-year life of the project. It provides an overview of the activities and serves as a guide to the wealth of information amassed on the website throughout this timinfo:eu-repo/semantics/publishedVersio
Social networks and perceived values: Gender differences in adolescents and young people
Get PDFEl objetivo de este artículo es analizar las diferencias de género en cuanto a los valores y los contra-valores que los adolescentes y los jóvenes perciben cuando interactúan en las redes sociales más populares, como YouTube e Instagram. Se han llevado a cabo 14 grupos focales (N=83) en tres comunidades autónomas de España (Euskadi, Cataluña y Baleares). Tomando como base el modelo de valores Hall-Tonna (Hall, 1995), se ha realizado un análisis de contenido utilizando el software ATLAS.ti. Los resultados reflejan que los valores más percibidos son la amistad para ellas y la diversión para ellos, con algunos matices en relación con los distintos tramos de edad (12-13 años, 15-16 años y 18-19 años). El contravalor más percibido en ambos géneros y en todas las edades es la falta de respeto por los derechos de las personas. Las conclusiones sobre las diferencias de género se dan principalmente en torno a los valores prestigio/imagen para ellas y logro/éxito para ellos, mientras que las similitudes se sitúan en la relevancia de los valores diversión/recreo, educación/conocimientos y amistad/pertenencia, así como en la percepción de los contravalores derechos/respeto y control/orden/disciplina.The aim of this article is to analyze gender differences in the values and counter-values perceived by adolescents and young people when they interact with the most popular social networks, such as YouTube and Instagram. Fourteen focus groups (N=83) were conducted in three autonomous communities of Spain (the Basque Country, Catalonia and the Balearic Islands). Based on the Hall-Tonna values model (Hall, 1995), a content analysis was carried out using ATLAS.ti. software. The results show that the most frequently perceived values are friendship for girls and fun for boys, although some nuances were found in relation to the different age groups (12-13 years, 15-16 years and 18-19 years). The most often perceived counter-value in both genders at all ages is the lack of respect for people’s rights. The conclusions reflect that the gender differences are mainly around the values prestige/image for women and achievement/success for men, while the similarities across gender lie in the relevance of the values play/recreation, education/knowledge and friendship/belonging, as well as in the perception of the counter-values rights/respect and control/order/disciplineinfo:eu-repo/semantics/publishedVersio