Repositorio Institucional UCSC (Univ. Católica de la Santísima Concepción)
Not a member yet
3697 research outputs found
Sort by
Neuromotor decline is associated with gut dysbiosis following surgical decompression for Degenerative Cervical Myelopathy
Get PDFDegenerative cervical myelopathy (DCM) describes a spectrum of disorders that cause progressive and chronic cervical spinal cord compression. The clinical presentation can be complex and can include locomotor impairment, hand and upper extremity dysfunction, pain, loss of bladder and bowel function, as well as gastrointestinal dysfunction. Once diagnosed, surgical decompression is the recommended treatment for DCM patients with moderate to severe impairment.
Our body is composed of a large community of microorganisms, known as the microbiota. Traumatic and nontraumatic spinal cord injuries (SCIs) can induce changes in the gut microbiota and gut microbiota derived metabolites. These changes have been reported as important disease-modifying factors after injury. However, whether gut dysbiosis is associated with functional neurological recovery after surgical decompression has not been examined to date.
Here, DCM was induced in C57BL/6 mice by implanting an aromatic polyether material underneath the C5–6 laminae. The extent of gut dysbiosis was assessed by gas chromatography and 16S rRNA sequencing from fecal samples before and after decompression. Neuromotor activity was assessed using the Catwalk test.
Our results show that DCM pre- and post- surgical decompression is associated with gut dysbiosis, without altering short chain fatty acids (SCFAs) levels. Significant differences in Clostridia, Verrumicrobiae, Lachnospiracea, Firmicutes, Bacteroidales, and Clostridiaceae were observed between the DCM group (before decompression) and after surgical decompression (2 and 5 weeks). The changes in gut microbiota composition correlated with locomotor features of the Catwalk. For example, a longer duration of ground contact and dysfunctional swing in the forelimbs, were positively correlated with gut dysbiosis. These results show for the first time an association between gut dysbiosis and locomotor deterioration after delayed surgical decompression. Thus, providing a better understanding of the extent of changes in microbiota composition in the setting of DCM pre- and postsurgical decompression
Áreas selecionadas em projetos de graduação em Formação Inicial de Professores em Pedagogia da Educação Física
Get PDFEl estudio tuvo por objetivo describir y clasificar los trabajos de titulación desarrollados entre los años 2009 al 2019 de la carrera de Pedagogía en Educación Física de una universidad pública no estatal del sur de Chile. Se utilizó un enfoque cuantitativo, utilizando estadística descriptiva para el análisis de datos. Se analizó un total de 212 tesis, para la clasificación se elaboró una propuesta que estableció 3 áreas temáticas, cuyos resultados exponen que la mayor cantidad de trabajos de titulación se encuentran en el área pedagógica, seguida por el área disciplinar y finalmente el área integral. Se concluye que estudios descriptivos en torno al análisis de tesis en un periodo de tiempo determinado permiten conocer y reorientar los procesos de formación inicial docente en Educación Física en torno a las demandas para una formación de calidad en relación con la malla curricular y normas institucionales establecidas
Strong column-weak beam relationship of 3D steel joints with tubular columns: Assessment, validation and design proposal
No full textThe study of moment connections in steel structures subjected to cyclic loads has been extensively studied, providing a great number of requirements, including the strong column-weak beam relationship, to guarantee a satisfactory cyclic performance. However, investigations on the cyclic performance of moment connections considering the bidirectional and axial load effects simultaneously with tubular columns are limited. This study aims to assess and validate the strong column-weak beam relationship of 3D steel moment connections using reduced order models. The simplified model (reduced order model) approach was employed to extend the range of beam and column elements sizes and reduce the experimental and computational costs. These models were calibrated from full-scale experimental studies. A great number of configurations with different beam and column sizes without loss of reliability and structural representativeness of the studied phenomenon were studied. A total of 13640 simplified models were developed. Results show a cyclic behavior controlled by the strong column-weak beam relationship to modify the joint’s failure mechanism. The increasing of strong column-weak beam relationship and the biaxial effect caused degradation of the strength and stiffness as well as in dissipated energy. An optimal strong column-weak beam relationship was obtained for all joint configurations analyzed. Finally, a robust design procedure is proposed, ensuring the cyclic behavior of end-plate moment connection with built-up box column including biaxial effect and axial load. Therefore, the use of this type of moment connection can be used in special and intermediate moment frames designed according to Seismic provisions
Conservative kidney management and kidney supportive care: Core components of integrated care for people with kidney failure
No full textIntegrated kidney care requires synergistic linkage between preventative care for people at risk for chronic kidney disease and health services providing care for people with kidney disease, ensuring holistic and coordinated care as people transition between acute and chronic kidney disease and the 3 modalities of kidney failure management: conservative kidney management, transplantation, and dialysis. People with kidney failure have many supportive care needs throughout their illness, regardless of treatment modality. Kidney supportive care is therefore a vital part of this integrated framework, but is nonexistent, poorly developed, and/or poorly integrated with kidney care in many settings, especially in low- and middle-income countries. To address this, the International Society of Nephrology has (i) coordinated the development of consensus definitions of conservative kidney management and kidney supportive care to promote international understanding and awareness of these active treatments; and (ii) identified key considerations for the development and expansion of conservative kidney management and kidney supportive care programs, especially in low resource settings, where access to kidney replacement therapy is restricted or not available. This article presents the definitions for conservative kidney management and kidney supportive care; describes their core components with some illustrative examples to highlight key points; and describes some of the additional considerations for delivering conservative kidney management and kidney supportive care in low resource settings
ChatGPT 3.5 argumentative behavior: Similarities and differences with human argumentative practice
Get PDFEl desarrollo de la inteligencia artificial (IA) ha abierto una nueva discusión sobre la capacidad lingüística de esta tecnología y su potencial impacto en todas las dimensiones de la actividad humana (Brynjolfsson y McAfee, 2014). A fin de evaluar similitudes o diferencias entre la capacidad lingüística de la IA y la humana, este trabajo analiza específicamente el comportamiento argumentativo en términos de los puntos de vista que adopta Chat GPT, versión 3.5, frente a una situación controversial expresada en un dilema moral del Cuestionario D.I.T. (Rest, 2013) y se compara con una muestra similar de adultos humanos (Noemi, 2019), sometida a la misma tarea discursiva. La investigación siguió un estudio comparativo de casos múltiples (Flick, 2020) a través de una metodología mixta (Johnson y Onwuegbuzie, 2004), que combinó un enfoque cuantitativo con uno cualitativo. Los resultados muestran que el 100% de la muestra de IH emite un punto de vista (a favor o en contra), mientras que de la muestra producida por el Chat GPT, sólo el 23,4% lo hace. Los resultados animan a pensar que las diferencias encontradas se podrían explicar por la debilidad de la IA de ser sensible al contexto (falta de una competencia pragmática relevante) y la inexistencia de un proceso de autoimplicación para enfrentar tareas de razonamiento moral
Thermoelectric properties of CrS2–xTex (x: 0, 1, 2) Dichalcogenides Monolayers: First-principles study
Get PDFIn this study, we conducted first-principles calculations interfaced with Boltzmann transport theory to examine the carrier-dependent thermoelectric properties of CrS2−xTex (x: 0, 1, 2) dichalcogenides monolayers. We conducted a systematic analysis of the structural, phonon band structures, elastic properties, electronic structures, and thermoelectric properties, of electron (e) and hole (h) doped CrS2−xTex (x: 0, 1, 2) dichalcogenides monolayers. The studied 2D TMDCs exhibit structural stability, as indicated by the negative formation energy. Additionally, the phonon band structures indicate no negative frequencies along any wave vector, confirming the dynamic stability of the CrS2−xTex monolayers. CrS2 and CrTe2 monolayers are semiconductors with direct bandgaps of 1.01 and 0.67 eV, respectively. A Janus CrSTe monolayer has a smaller bandgap of 0.21 eV. Temperatures range between 300 and 500 K, and concentrations of e(h) doped in the range of 1.0 × 1018−1.0 × 1020 cm−3 are used to compute the thermoelectric transport coefficients. The low lattice thermal conductivity is predicted for the studied compounds, among which Janus CrSTe and CrTe2 have the minimum value of κlat ≈ 1 W/mK @ 700 K. The figure-of-merit ZT projected value at the optimal e(h) doping concentration for the CrS2 monolayer is as high as 0.07 (0.09) at 500 K. Our findings demonstrate how to design improved thermoelectric materials suitable for various thermoelectric devices
The art of prompts' formulation: Limitations, potential, and practical examples in large language models
Get PDFIntroducción: La “ingeniería de prompt” es crucial en el uso de modelos de IA como GPT-3 y GPT-4, ya que ayuda a obtener respuestas efectivas en áreas como generación de texto y programación. Un buen prompt mejora la calidad de las respuestas. El estudio analizó el funcionamiento de los LLMs y recogió consejos para la ingeniería de prompt, examinando también las limitaciones tecnológicas y el impacto del lenguaje del usuario.
Método: Se describieron los grandes modelos de lenguaje desde su evolución hasta la arquitectura Transformers en 2017. Se evaluaron las respuestas de ChatGPT 3.5 y 4.0 en dos casos de estudio para analizar la complejidad y personalización de los prompts.
Resultados: En los casos de estudio, se encontró que agregar contexto y especificidad mejoraba las respuestas de los modelos. Las respuestas detalladas y personalizadas resultaban en mayor precisión y relevancia.
Conclusión: La calidad de las respuestas de los LLMs depende de la precisión y especificidad de los prompts. La personalización y el lenguaje técnico adecuado mejoran la interacción con la Inteligencia Artificial (IA), lo que aumenta la satisfacción del usuario. Los futuros estudios deberían analizar los campos semánticos y las métricas para evaluar la calidad de las respuestas de la IA
Adaptation and validation of the teacher as a social context questionnaire (TASCQ) to the Chilean university context
Get PDFEl presente estudio traduce y adapta el Teacher as Social Context Questionnaire (TASCQ) al contexto universitario chileno y examina sus propiedades psicométricas. Este instrumento mide la percepción que tienen los estudiantes de tres dimensiones (autonomía, estructura, involucramiento) del apoyo docente planteadas por la teoría de autodeterminación. Hasta el momento no existen validaciones en español de esta escala y su uso en contexto universitario es limitado. Se realizan análisis factoriales confirmatorios para tres modelos en una muestra de 315 estudiantes de una universidad chilena. Los resultados muestran un ajuste aceptable para una estructura de tres factores y una bifactorial, no así para el modelo de un factor. En conclusión, los resultados del análisis de dimensionalidad del modelo bifactorial no fueron favorables, siendo la estructura de tres factores la que mejor se ajusta a la muestra, lo cual es consistente con análisis factoriales realizados en muestras de estudiantes de secundaria y universitarios
Archaeozoology supports a holistic view on fish assessments in large rivers-A case study from the Volga River: From quantitative data and ancient DNA to biodiversity analysis
Get PDFKnowledge of the historical and present dynamics of populations of migratory fish can promote our understanding of factors affecting their recruitment and abundance. Taxonomic identification of 23,802 bone remains and 13,539 scales of fish from 30 archaeological sites along Volga River revealed that they belonged to 41 different fish species. These data allow for retrospective comparisons and highlight the potential of archaeozoology in conservation biology. Sturgeons and salmonids are vulnerable to the impacts of fishery and climatic change. The sharp decline in the numbers of Starry sturgeon (Acipenser stellatus), Caspian trout (Salmo caspius), and Caspian Inconnu (Stenodus leucichthys) from the Volga in the 17th and 18th centuries was likely related to a cooling period (“Little Ice Age”). At present, the population numbers of all anadromous sturgeons and salmonids of the Volga River are critically low. In the Volga basin over the past two millennia, the sterlet (Acipenser ruthenus) has had a very large population number, high genetic (haplogroups and haplotypes) diversity, and large body sizes. Genetic analysis (aDNA and eDNA) have great potential to expand the knowledge of fish populations along large rivers and to improve long-term biomonitoring. Therefore, analyses of historical data, conventional surveys, as well as the inclusion of genetic approaches complement each other in the development of effective conservation strategies
Impact of a culturally adapted digital literacy intervention on older people and its relationship with health literacy, quality of life, and well-being
Get PDFIntroduction: Older people are the group with the greatest digital gap, so their digital literacy is important to improve the conditions in which they age.
Methods: A study was conducted with pre- and post-evaluation of a digital literacy (DL) intervention in people aged 60 years and over. A total of 56 participants (experimental group N = 32 and control group N = 24) were recruited for convenience in community centers. The intervention was adapted to the needs of the participants, there were five face-to-face sessions and remote reinforcement for three months, carried out by trained university students for five months. Sociodemographic variables such as self-perception of socioeconomic level and education, among others, were evaluated. The impact was assessed using the digital literacy scale (MDPQ16), indicators of frequency and types of internet and mobile phone use, health literacy (SAHLSA and NSV), quality of life (SF-12), hedonic well-being (Diener’s SWLS and Cummins’ PWI) and perceived social support using the Zimet scale.
Results: The intervention had a significant impact with an effect size of r = 0.27 on digital literacy, separate t-test comparisons revealed a markedly significant change for digital literacy in the experimental group, before and after the pre-post t-test(31) = 3.56, p = 0.001, but not in the control group, t(23) = 0.082, p = 0.93. No direct impact on health literacy, health-related quality of life, and hedonic well-being was identified. We examined the indirect impact of change in digital literacy and found that it correlated with improvements in well-being and social support, as well as quality of life. Individuals with significant changes were detected and compared with those who did not change.
Discussion: Evaluation that contributes by identifying elements for improvement in future interventions and discusses the importance of culturally adapting continuing education in older people