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Enhancing bandwidth and efficiency with slotted ground planes embedding antenna boosters
Get PDFThe deployment of wireless devices has increased exponentially in recent years, not only for mobile applications but also for IoT. Typically, these IoT devices exchange data with other devices by means of wireless connections, where battery consumption depends on the antenna system’s efficiency. In applications where long battery life and reliable transmission are essential, improving the efficiency of the antenna is crucial. This study aims to investigate how shaping the ground plane of a wireless device can enhance bandwidth and antenna efficiency, specifically in low-frequency bands of 824–960 MHz, a common frequency band used in IoT where transmitting a small amount of data provides long battery life. Specifically, this work shows that by adding a slot in the ground plane, the current distribution is enlarged, which enables the excitation of its fundamental mode and, consequently, enhances the bandwidth and antenna efficiency by 2 dB. This approach is assessed using three different printed circuit boards (PCBs) that aim to characterise different form factors of IoT devices. A physical prototype is built to validate the results obtained in simulationsinfo:eu-repo/semantics/publishedVersio
Demand-side constraints affecting consumer attitudes toward digital short-term rental platforms across five European countries: a signaling theory perspective
Get PDFPurpose: Given the rapid progress in digitalization, the essence of exchange has been reformulated with the help of digital platforms allowing a temporary access of ownership to the global travel industry. Drawing on signaling theory, this study analyzes the demand-side constraints influencing consumers’ attitudes toward digital short-term rental platforms through a cross-country analysis. | Design/methodology/approach: This study performs a cross-country segmentation analysis in five European countries (i.e. UK, Croatia, Italy, Turkey and Spain) by using survey data from 534 consumers and structural equation models. | Findings: The findings indicate that perceived risk and lack of service quality exert a significant influence on consumers’ attitudes, with distrust serving as a mediation mechanism. Digital short-term rental platform managers, hosts and policymakers should collaboratively implement trust-building strategies, including fostering third-party quality certifications, enhancing cancellation flexibility and ensuring the provision of transparent information with an intent to mitigate perceived risk and reduce distrust. | Originality/value: This study provides a timely contribution to the reshaping of consumer behavior and stimulates a discussion regarding the underexplored attitudes of customers who have not previously used digital short-term rental platforms and their important demand constraints, putting an emphasis on the signals with a dark side which could be interpreted differently from country to country.info:eu-repo/semantics/acceptedVersio
UEC present i futur: integració vs. necessitat
Get PDFAquest treball analitza les Unitats d’Escolarització Compartida (UEC) com a recurs educatiu per a joves amb dificultats d’adaptació al sistema ordinari. Des de l’experiència de pràctiques, es qüestiona si les UEC són una oportunitat o una mesura segregadora. Els resultats mostren beneficis educatius i personals quan hi ha una mirada integral, però també riscos d’etiquetatge. Es conclou que cal vetllar perquè siguin espais d’inclusió real i no de segregació encoberta.info:eu-repo/semantics/publishedVersio
Justicia Restaurativa y siniestralidad vial. Aproximación en el contexto de España
Get PDFEste artículo se propone justificar la idoneidad de abordar los delitos de tráfico, especialmente aquellos que generan víctimas, con prácticas de la justicia restaurativa. Se reflexiona sobre algunos rasgos clave de las prácticas restaurativas, poniendo el énfasis en su respuesta a las necesidades de víctimas y victimarios, y a su adaptabilidad a situaciones y momentos diversos del proceso penal. La fundamentación teórica y la apreciación práctica de la justicia restaurativa tienen ya un considerable recorrido, pero recientemente ha recibido un importante impulso normativo. Sin embargo, un somero análisis de la situación actual en España revela que se puede avanzar mucho más en la integración de prácticas restaurativas en los procesos de la justicia penal.info:eu-repo/semantics/publishedVersio
Pulsed Laser Synthesis of Carbon Nanostructures from Organic Molecular Liquids: Structure, Kinetics and Photophysical Properties
Get PDFThe striking one-step bottom-up synthesis of carbon nanoparticles (CNPs) from visible and near infrared (NIR) light transparent air-equilibrated liquid aromatic compounds (benzene, toluene, chlorobenzene, aniline, pyrrole, and thiophene) under unfocused pulsed nanosecond laser irradiation (532/1064 nm) is reported. The formation of CNPs follows zero-order kinetics with an induction period dependent on the reactivity of the organic precursor. Experimental evidence suggests a surface-catalyzed photochemical process involving a partial change in C-atom hybridization from sp2 to sp3, with oxygen-based functional groups passivating the surface of the nanostructures. The presence of additional heteroatoms depends on the structure and composition of the precursor. Contingent on the starting compound, the prepared CNPs can be classified as amorphous carbon nanodots (CNDs) or layered curved-graphene quantum dots (c-GQDs), resembling nano-onion fragments. CNDs are obtained from substituted benzenes or heterocyclic compounds, whereas c-GQDs can be synthesized from benzene. Photophysical characterization of the CNPs shows both wavelength-dependent excitation and emission bands, with constant emission quantum yields in the 1–10% range, and wavelength-dependent emission decays displaying several lifetime components in the range 1–20 ns. Triplet exciton lifetimes longer than 5 µs and wavelength-dependent singlet oxygen production quantum yields in the 10–40% range have been measured.info:eu-repo/semantics/publishedVersio
Measurement of ϕ(1020) meson production in fixed-target pNe collisions at sNN = 68.5 GeV
Get PDFThe first measurement of ϕ(1020) meson production in fixed-target pNe collisions at sNN = 68.5 GeV is presented. The ϕ(1020) mesons are reconstructed in their K+K− decay in a data sample consisting of proton collisions on neon nuclei at rest, corresponding to an integrated luminosity of 21.7 ± 1.4 nb−1, collected by the LHCb detector at CERN. The ϕ(1020) production cross-section in the centre-of-mass rapidity range of −1.8 < y*< 0 and transverse momentum range of 800 < pT< 6500 MeV/c is found to be σ = 182.7 ± 2.7 (stat.) ± 14.1 (syst) μb/nucleon. A double-differential measurement of the cross-section is also provided in four regions of rapidity and six regions of transverse momentum of the ϕ(1020) meson and compared with the predictions from Pythia and EPOS4, which are found to underestimate the experimental values.info:eu-repo/semantics/publishedVersio
A Comparative evaluation of the quality and feasibility of ‘over-the-head’ cardiopulmonary resuscitation by a single rescuer: pocket mask vs. bag-valve mask - A pilot study
Get PDFAim: The present study evaluated the feasibility and quality of cardiopulmonary resuscitation (CPR) performed by a single rescuer, comparing the over-the-head (OTH) technique using mouth-to-pocket mask ventilation with bag-valve mask (BVM) ventilation. The study analyzed the chest compression (CC) quality, ventilation adequacy, interruption minimization, and the rescuers’ perceived difficulty. Methods: A randomized simulation crossover study was conducted with 26 lifeguard students trained in basic life support and both ventilation techniques. All of the participants performed two solo CPR trials (2 min each) using OTH with a pocket mask or BVM on a manikin connected to a feedback system (Little Anne QCPR, Laerdal). The overall CPR quality, ventilation, and CC quality were assessed, along with the perceived difficulty (scale 0–5). A 5 min rest was provided between the trials. Results: The overall CPR quality was excellent for both techniques with a median of 98% (IQR: 97–99) for BVM-OTH and 99% (IQR: 94–99) for Pocket-OTH (p = 0.31). The ventilation quality was better when using BVM-OTH (100%, IQR: 99–100) compared to that with Pocket-OTH (99%, IQR: 77–100; p = 0.046). No differences were found in the CC quality (99%, IQR: 99–100; p = 0.24). However, Pocket-OTH had more CCs and shorter interruption times (p ≤ 0.001). The perceived difficulty was low for both techniques. Conclusions: Both techniques enable high-quality CPR when performed alone. Given that no clinically relevant differences emerged in the resuscitation quality, the OTH technique using a pocket mask offers a viable alternative, particularly in scenarios with a single rescuer and limited resources.info:eu-repo/semantics/publishedVersio
Academic and non-academic career paths of international and domestic PhD holders
Get PDFSome countries have strong culturally rooted practices and policies to incentivize their PhD candidates to develop their doctoral studies abroad. Their programs provide cultural and methodological diversity opportunities and globally oriented career prospects. In the last years, many of those countries are increasingly developing their own domestic doctoral programs, which may offer career benefits due to their strong connections to the local research and academic environment. The career paths of 126 PhD holders working in Paraguay, a country in which doctoral studies abroad intersect with national-based doctoral programs, were examined using the ECRID survey. The perceptions of those who completed their doctoral studies domestically and those who studied abroad were compared in terms of the usefulness of the skills provided by their respective PhD programs. The results showed that most PhD holders in Paraguay work full-time in the academic sector. The percentage of PhD holders employed in non-academic roles reflects the diversity of career options available to PhDs holders in the Paraguayan labour market. Furthermore, results indicated how the participants re-signified the skills acquired during the doctoral program to adapt them to various professional settings. This process underscores the emerging demands of the current labour market and the necessity for universities to adjust doctoral training models to better equip graduates for diverse professional paths. This adjustment includes institutional support to reduce cultural shock and subsequent burnout levels. Pioneering results from the Paraguayan context provide empirical evidence to enrich the reflection on the resources and opportunities for PhD holders at both structural and organizational levels.info:eu-repo/semantics/publishedVersio
Motor imagery enhances core training effects on lumbar proprioception in elite swimmers: a randomized controlled trial
Get PDFLumbar proprioception is essential for executing effective movements during the undulatory underwater swimming (UUS) technique. Core exercises are commonly used to strengthen the musculature involved in UUS, and variations in sensory input and attentional focus may modulate neuromuscular responses, influencing training outcomes. This study investigated the impact of repeated maximal lumbar movements performed with closed eyes and motor imagery on lumbar proprioception in elite swimmers, compared to performing the same exercises with proper technique and controlled breathing alone. Methods: A total of 57 elite swimmers (34 males, 20.2 ± 4.2 years; 23 females, 20.7 ± 3.3 years) volunteered and completed the study. Participants were randomly assigned to two experimental groups (EG1 and EG2) and one control group (CG). All groups followed the same swimming and physical training program, with EG1 and EG2 completing additional lumbar flexion-extension exercises. Both EG1 and EG2 performed three sets of 10 repetitions at a controlled breathing pace, 6 days per week for 11 weeks. EG1 completed the exercises with eyes closed and motor imagery; EG2 performed the same exercises focusing only on technique. Lumbar joint position sense in the sagittal plane was assessed using an electrogoniometer while seated on a Swiss ball. Results: Significant group differences were found for relative repositioning error (REr) (F = 6.75, p = 0.012) and absolute error (ABSEr) (F = 7.34, p = 0.009). EG1 showed large positive effect sizes (REr d = 0.91; ABSEr d = 1.24), EG2 showed negative effects (REr d = −0.56; ABSEr d = −1.17), and CG had no meaningful changes. Conclusion: Motor imagery enhances proprioceptive accuracy beyond physical training alone. Trial Registration: NCT06747702
Attitudes toward gender equality and the acceptability of gender-based violence in a sample of future early childhood and primary teachers
Get PDFGender equality education in the classroom is a very relevant tool to combat gender inequality and gender-based violence (GBV). The aim of this study was to assess the attitudes toward gender equality in the school context and the acceptability of GBV of a sample university education students. A total of 148 students enrolled in the final year in Primary Education (55.4%) and Early Childhood Education (44.6%) degrees in Spain participated in this study. The design was correlational and cross-sectional. Among other gathered data, the School Doing Gender/Teachers Scale (SDG/t) and the Acceptability of Intimate Partner Violence Against Women Scale (A-IPVAW) were administered. The results obtained showed that 74.3% of the future teachers believed they did not have sufficient knowledge of equality and coeducation, specifically regarding the design of equality plans and non-sexist language. Significant differences in the acceptability of GBV as a function of sexual orientation were found, with special emphasis on bisexual people, who in this study and elsewhere have exhibited the greatest degree of acceptability of GBV. Results highlighted the urgent need for more training in gender equality and coeducation in order to help shape a more feminist society and reduce GBV.info:eu-repo/semantics/publishedVersio