Analyzing digital societal interactions and sentiment classification in Twitter (X) during critical events in Chile

This study explores the influence of social media content on societal attitudes and actions during critical events, with a special focus on occurrences in Chile, such as the COVID-19 pandemic, the 2019 protests, and the wildfires in 2017 and 2023. By leveraging a novel tweet dataset, this study introduces new metrics for assessing sentiment, inclusivity, engagement, and impact, thereby providing a comprehensive framework for analyzing social media dynamics. The methodology employed enhances sentiment classification through the use of a Deep Random Vector Functional Link (D-RVFL) neural network, which demonstrates superior performance over traditional models such as Support Vector Machines (SVM), naive Bayes, and back propagation (BP) neural networks, achieving an overall average accuracy of 78.30% (0.17). This advancement is attributed to deep learning techniques with direct input–output connections that facilitate faster and more precise sentiment classification. This analysis differentiates the roles of influencers, press radio, and television handlers during crises, revealing how various social media actors affect information dissemination and audience engagement. By dissecting online behaviors and classifying sentiments using the RVFL network, this study sheds light on the effects of the digital landscape on societal attitudes and actions during emergencies. These findings underscore the importance of understanding the nuances of social media engagement to develop more effective crisis communication strategies

A Probability Approach to the Study on Uncertainty Effects on Gamma Index Evaluations in Radiation Therapy

Two datasets of points of known spatial positions and an associated absorbed dose value are often compared for quality assurance purposes in External Beam Radiation Therapy (EBRT). Some problems usually arise regarding the pass fail criterion to accept both datasets as close enough for practical purposes. Instances of this kind of comparisons are fluence or dose checks for intensity modulated radiation therapy, modelling of a treatment unit in a treatment planning system, and so forth. The gamma index is a figure of merit that can be obtained from both datasets; it is widely used, as well as other indices, as part of a comparison procedure. However, it is recognized that false negatives may take place (there are acceptable cases where a certain number of points do not pass the test) due in part to computation and experimental uncertainty. This work utilizes mathematical methods to analyse comparisons, so that uncertainty can be taken into account. Therefore, false rejections due to uncertainty do not take place and there is no need to expand tolerances to take uncertainty into account. The methods provided are based on the rules of uncertainty propagation and help obtain rigorous pass/fail criteria, based on experimental information

Lithium causes differential effects on postsynaptic stability in normal and denervated neuromuscular synapses

Lithium chloride has been widely used as a therapeutic mood stabilizer. Although cumulative evidence suggests that lithium plays modulatory effects on postsynaptic receptors, the underlying mechanism by which lithium regulates synaptic transmission has not been fully elucidated. In this work, by using the advantageous neuromuscular synapse, we evaluated the effect of lithium on the stability of postsynaptic nicotinic acetylcholine receptors (nAChRs) in vivo. We found that in normally innervated neuromuscular synapses, lithium chloride significantly decreased the turnover of nAChRs by reducing their internalization. A similar response was observed in CHO-K1/A5 cells expressing the adult muscle-type nAChRs. Strikingly, in denervated neuromuscular synapses, lithium led to enhanced nAChR turnover and density by increasing the incorporation of new nAChRs. Lithium also potentiated the formation of unstable nAChR clusters in non-synaptic regions of denervated muscle fibres. We found that denervation-dependent re-expression of the foetal nAChR γ-subunit was not altered by lithium. However, while denervation inhibits the distribution of β-catenin within endplates, lithium-treated fibres retain β-catenin staining in specific foci of the synaptic region. Collectively, our data reveal that lithium treatment differentially affects the stability of postsynaptic receptors in normal and denervated neuromuscular synapses in vivo, thus providing novel insights into the regulatory effects of lithium on synaptic organization and extending its potential therapeutic use in conditions affecting the peripheral nervous system.Fil: Zelada, Diego. Universidad Católica de la Santísima Concepción; ChileFil: Barrantes, Francisco Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires"; ArgentinaFil: Henríquez, Juan Pablo. Universidad Católica de la Santísima Concepción; Chil

Sistema de automatización integrado

Posteriormente a la implementación del proyecto de investigación del año 2006 denominado “Aplicaciones innovadoras para el control de equipos eléctricos usando Internet y dispositivos móviles”, se hace necesaria la incorporación de nuevos elementos de automatización al proyecto, lo que llevó al equipo de investigación a la mejora de los componentes, principalmente la construcción de la tarjeta electrónica y a la incorporación de nuevos elementos, logrando superar las limitantes presentadas en el proyecto de investigación del año 2006, por lo que el presente documento muestra el Sistema de Automatización Integrado implementado en la Regional de Santa Ana

Square root computation over even extension fields

This paper presents a comprehensive study of the computation of square roots over finite extension fields. We propose two novel algorithms for computing square roots over even field extensions of the form \F_{q^{2}}, with $q=p^n,$ $p$ an odd prime and $n\geq 1$. Both algorithms have an associate computational cost roughly equivalent to one exponentiation in \F_{q^{2}}. The first algorithm is devoted to the case when $q\equiv 1 \bmod 4$, whereas the second one handles the case when $q\equiv 3 \bmod 4$. Numerical comparisons show that the two algorithms presented in this paper are competitive and in some cases more efficient than the square root methods previously known

A note on the cost of computing odd degree isogenies

Finding an isogenous supersingular elliptic curve of a prescribed odd degree is an important building block for all the isogeny-based protocols proposed to date. In this note we present several strategies for the efficient construction of odd degree isogenies, which outperform previously reported methods when dealing with isogeny degrees in the range $[7, 2^{20}].

Revisão sistemática sobre competências de investigação em estudantes do ensino superior

This study employed a systematic review method following PRISMA guidelines to assess the scientific production regarding research competencies in higher education students. We explored the Web of Science and Scopus databases, covering the period from 2013 to 2022. The sample included 32 studies that met the established inclusion criteria. The results revealed a limited number of studies in South America, the use of non-representative sample sizes, a shortage of theoretical models to systematize competencies, and the use of unreliable and invalid measurements. The findings from these studies indicated that university students exhibit deficiencies in literature review, methodological, and results communication skills.Este estudio aplicó un método de revisión sistemática siguiendo directrices de la declaración PRISMA. Se analizó la producción científica sobre competencias de investigación en estudiantes de Educación Superior. Se exploraron las bases Web of Science y Scopus, considerando el período 2013-2022. La muestra fue de 32 estudios que cumplieron los criterios de inclusión establecidos. Los resultados evidenciaron una escasa productividad de estudios en América del Sur, el uso de tamaños muestrales poco representativos, escasos modelos teóricos para sistematizar competencias y la aplicación de mediciones carentes de fiabilidad y validez. Los hallazgos de estos estudios revelaron que los estudiantes universitarios presentan deficiencias en habilidades de revisión de literatura, metodológicas y de comunicación de resultados.Este estudo aplicou um método de revisão sistemática seguindo as diretrizes da declaração PRISMA. Foi analisada a produção científica sobre competências de investigação em estudantes do Ensino Superior. Foram exploradas as bases de dados Web of Science e Scopus, considerando o período de 2013-2022. A amostra foi composta por 32 estudos que atenderam aos critérios de inclusão estabelecidos. Os resultados demonstraram uma escassa produtividade de estudos na América do Sul, o uso de amostras não representativas, escassos modelos teóricos para sistematizar as competências e a aplicação de medições carentes de confiabilidade e validade. Os achados desses estudos revelaram que os estudantes universitários apresentam deficiências em habilidades de revisão de literatura, metodológicas e de comunicação de resultados