Repositorio Institucional UCSC (Univ. Católica de la Santísima Concepción)
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América Latina na pesquisa em relações públicas. Análise de três periódicos científicos (2000-2023)
Get PDFMediante el análisis de contenido de todos los artículos publicados entre 2000 y 2023 en tres de las principales revistas del campo de las Relaciones públicas –Public Relations Review (PRR), Corporate Communications (CC) y Journal of Public Relations Research (JPRR)– se examina la presencia de casos de América Latina en 39 artículos, identificando, entre otras variables, autores, objetivos, temas, afiliación institucional, redes, países representados, metodologías, resultados y conclusiones. Lo anterior, para evaluar la situación de la investigación sobre América Latina en las Relaciones públicas, la Comunicación estratégica y la Comunicación corporativa. Se concluye con sugerencias para investigaciones futuras y una propuesta general para la investigación en el subcontinente: los resultados no son del todo alentadores
Transition from synchronous to asynchronous mechanisms in 1,3-dipolar cycloadditions: A polarizability perspective
No full textContext: This study investigates the energetic and polarizability characteristics of three 1,3-dipolar cycloaddition reactions between diazene oxide and substituted ethylenes, focusing on the transition from synchronous to asynchronous mechanisms. Synchronicity analysis, using the reaction force constant, indicates that the bond evolution process becomes increasingly decoupled as the number of cyano groups increases. Polarizability analysis reveals that isotropic polarizability reaches its maximum near the transition state in all cases, while anisotropy of polarizability shifts from the transition state toward the product direction as asynchronicity increases. The larger the shift, the more asynchronous the mechanism, as refected by the weight of the transition region. A detailed examination of the parallel and perpendicular polarizability components to the newly formed sigma bonds shows that the evolution of the parallel component is closely aligned with the energetic changes along the reaction coordinate, particularly in the synchronous reaction. We have also identifed a relationship between the displacement in the maximum state of the parallel component from the transition state and the synchronicity of the mechanism. The larger the displacement, the more asynchronous the mechanism. These fndings suggest that asynchronous 1,3-dipolar cycloaddition mechanisms are characterized by a decoupling of isotropic and anisotropic polarizabilities and a shift in the maximum polarizability state of the parallel component toward the product direction.
Methods: Density functional theory calculations were performed at the B3LYP/6–311+ +G(d,p)//B3LYP/6-31G(d,p) level of theory. The polarizability was calculated at each point of the reaction path, obtained using the intrinsic reaction coordinate method, as implemented in Gaussian 16
Cognitive skills and critical thinking interventions for the development of academic writing in higher education students: A systematic review
Get PDFEsta revisión sistemática examina las intervenciones diseñadas para mejorar las habilidades de escritura académica y se enfatiza la importancia de la interacción entre los estudiantes, instructores y/o tutores de escritura durante el proceso de composición. El objetivo principal de esta revisión es El objetivo de esta revisión sistemática es caracterizar las intervenciones centradas en habilidades cognitivas para el desarrollo de escritura académica en estudiantes de educación superior que se han implementado en países latinoamericanos e iberoamericanos. Para llevar a cabo esta Revisión Sistemática, se siguieron las recomendaciones PRISMA y además, se implementó una estrategia de investigación documental y análisis de contenido con el propósito de examinar las diferentes definiciones de habilidades cognitivas utilizadas en los estudios seleccionados. En total, se identificaron y analizaron nueve artículos que cumplieron con los criterios establecidos. Se ofrece una visión integral y actualizada de las intervenciones dirigidas a mejorar las habilidades de escritura académica en el contexto de la educación superior, enfocándose en la aplicación de habilidades cognitivas y pensamiento crítico como herramientas clave para este propósito
Searching possible SARS-CoV-2 main protease inhibitors in constituents from herbal medicines using in silico studies
No full textThe largest threat to civilization since the Second World War is the spread of the new coronavirus disease (COVID-19). Therefore, there is an urgent need for innovative therapeutic medicines to treat COVID-19. Reusing bio-actives is a workable and efficient strategy in the battle against new epidemics because the process of developing new drugs is time-consuming. This research aimed to identify which herbal remedies had the highest affinity for the receptor and assess a variety of them for potential targets to suppress the SARS-CoV-2 Mpro. The use of AutoDock Vina for structure-based virtual screening was done first due to the importance of protein interactions in the development of drugs. Molecular docking was used in the comparative study to assess 89 different chemicals from medicinal herbs. To anticipate their effectiveness against the primary protease of SARS-CoV-2, more analysis was done on the ADMET profile, drug-likeness, and Lipinski’s rule of five. The next step involved three replicas of 100 ns-long molecular dynamics simulations on the potential candidates, which were preceded by calculations of the binding free energy of MM-GBSA. The outcomes showed that Achyrodimer A, Cinchonain Ib, Symphonone F, and Lupeol acetate all performed well and had the highest 6LU7 binding affinities. Using RMSD, RMSF, and protein-ligand interactions, the stability of the protein-ligand complex was assessed. The studies indicate that bioactive substances obtained from herbal medicines may function as a COVID-19 therapeutic agent, necessitating additional wet lab research to confirm their therapeutic potential, efficacy, and pharmacological capacity against the condition
Evaluation of linkage disequilibrium between CYP2D6 gene polymorphisms associated with breast cancer in women
Get PDFIntroducción: El gen CYP2D6 es altamente polimórfico y está involucrado en el metabolismo de una gran variedad de medicamentos y xenobióticos. Se han estudiado tres variantes alélicas del gen (rs3892097, rs1065852 y rs28371725) en relación con el cáncer de mama, pero se desconoce el grado de ligamiento genético entre ellas.
Objetivo: Probar si los tres SNPs asociados a cáncer de mama se heredan en bloque.
Método: Se obtuvieron los genotipos de 280 SNPs del gen CYP2D6 desde la base de datos 1000Genomes y se analizó el desequilibrio de ligamiento entre los tres SNPs asociados al cáncer de mama y los otros 277 SNPs del gen. Se usó un umbral de r2= 0.7 para identificar loci en desequilibrio de ligamiento.
Resultados: Se encontró una fuerte correlación entre rs3892097 y rs1065852 en Europa y Latinoamérica. Además, se identificaron once polimorfismos con un alto nivel de ligamiento, cuatro de los que tienen un efecto de mutación no sinónima.
Conclusiones: Ambos polimorfismos podrían tener un efecto causal sobre el cáncer de mama o que uno de ellos está asociado por ligamiento. Continuar estudiando ambos polimorfismos y considerar para su análisis los once nuevos, tendría relevancia profundizar el conocimiento en relación al cáncer de mama en mujeres
Mapping the research about organisations in the latin american context: a bibliometric analysis
No full textThe Latin American region has attracted a great amount of interest among management and organizational scholars in recent years. The distinctive economic, social, and institutional features of the region represent a unique opportunity for theory building and testing in management and business research. This research answers the following overarching question: How the research about organizations in the Latin American context has evolved and how could it move forward? We perform an in-depth analysis consisting of a systematic review and bibliometric techniques (i.e., co-occurrence, co-citation, and co-authorship network analysis) of 1940 peer-reviewed articles published in the field during the 2004–2021 period. We examine the most influential publications, authors, journals, and research organizations. Building on our analysis and results, we describe current research hotspots and suggest avenues for future research. Our results contribute to a broad discussion relative to the relevance of context in the organizational research community, providing the first holistic analysis of it
Investigating the properties of shrub biomass pellets through additive and sawdust admixing
No full textThis study investigated pellets produced using shrub biomass blended with pine sawdust to improve their physical and combustion properties by incorporating additives. First, the properties of pellets produced at different temperatures were analyzed. Pellets produced using pine sawdust blended with Teline monspessulana and Ulex europaeus biomasses (80/20 %m/m) exhibited good properties when prepared at 50–60 ◦C, whereas pellets produced using Rubus ulmifolius exhibited better characteristics at lower temperatures. The results showed that further studies on the physical properties and operational conditions of biomass from Ulex europaeus and Rubus ulmifolius are required. Furthermore, pellets blended with Teline monspessulana were evaluated using starch and lignin as binders, which exhibited all the physical properties of ISO 17225–6 when 1 wt% lignin was added owing to the stronger bonding induced by the additive. Because the fuel indices indicated a high corrosion risk, the additive CaO was used to improve the combustion performance of pellets blended with Teline monspessulana biomass and binders. The content of particulate matter smaller than 2.5 and 10 μm decreased by approximately 50%, and the crystallinity of the bottom ash, which usually contains undesirable elements, was improved by adding 1 wt% CaO, which raised the melting temperature of the ash
PEBAX polymer inclusion hydrophobic deep eutectic solvent membranes for pervaporation of biobutanol: Mass transfer and COSMO-RS analysis
No full textDeep Eutectic Solvent(DES) and specifically Hydrophobic Deep Eutectic Solvents (HDES) are considered a relatively novel class of solvents, which show good features to include them in pervaporation membranes. Polymer inclusion HDES membranes offer a separation media, which shows a faster molecular diffusion than polymeric membranes, combining the best properties of liquid and polymer membranes, such a high selectivity with high burst pressure and durability. The aim of this work focuses on the development of different PEBAX/ lidocaine-thymol [2:1] (Lidol HDES) membranes by the temperature-induced phase-inversion technique to be used in the pervaporation process to recover butanol from ABE model solution. The mass transfer modeling through the membrane using the resistances-in-series approach was implemented to find the mass transfer resistance distribution. The polymer inclusion membranes showed improved results for the butanol/water selectivity compared to the single PEBAX membrane used as a reference. The flux of butanol obtained with the 30 % w/w Lidol HDES membrane was 0.112 kg m− 2 hr− 1. The flux of water was 0.445 kg m− 2 hr− 1 showing a selectivity value for butanol/water of 20 % bigger than single PEBAX membrane. The improvement in the selectivity can be explained by the synergic effect of the HDES in the membrane. After use, the polymer inclusion membrane consistently demonstrated a stable performance in effectively separating butanol from the ABE solution. It was seen that the overall resistance decreases as the liquid flow rate increases; regarding the liquid side resistance, it becomes important at smaller flow rates and is almost negligible for turbulent regimen
Psychometric properties of the SocioEmotional Skills Instrument for Teachers using network approach: English and Spanish version
Get PDFThe importance of socioemotional teaching skills has been highlighted for its link with better academic, social, emotional, and behavioral results of students, as well as for its contribution to the work wellbeing, mental health, and prosperity of teachers. However, there are few instruments that measure these skills in teachers in the context of their professional practice. The purpose of this research was to analyze the psychometric properties of the socioemotional Skills Instrument for Teachers (SEMS-IT). An instrumental design and a sample of 853 Chilean secondary school teachers were used. To evaluate the dimensional structure of the instrument, a portion of the sample (n = 468) underwent a network estimation method with exploratory graph analysis (EGA) using a Gaussian GLASSO model. Then, in order to confirm the structural consistency and stability of the items, the analysis was replicated in a second sample (n = 385), where these results were additionally contrasted with those of the confirmatory factor analysis (CFA). The EGA findings confirmed a structure of four dimensions and 19 items in total: (a) cognitive management of teacher emotion (four items), (b) teacher empathic concern (four items), (c) teacher–student relationship (four items), and (d) adverse classroom climate (seven items), with a 7-point Likert scale response format. The CFA showed good and acceptable fit indicators, X2(171) = 354.546 (p < 0.001), Comparative Fit Index (CFI) = 0.971, Tucker–Lewis index (TLI) = 0.966, Root Mean Square Error of Approximation (RMSEA) = 0.061, and Standardized Root Mean Square Residual (SRMR) = 0.062. In conclusion, a tool for the assessment of teachers’ socioemotional skills, valid for school-based educational research, is provided. Implications of the findings at the theoretical and practical levels are discussed, as well as limitations and future projections for future research