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A High-Resolution LED Stimulator for Steady-State Visual Stimulation : Customizable, Affordable, and Open Source
No full textPublisher Copyright: © 2024 by the authors.Visually evoked steady-state potentials (SSVEPs) are neural responses elicited by visual stimuli oscillating at specific frequencies. In this study, we introduce a novel LED stimulator system explicitly designed for steady-state visual stimulation, offering precise control over visual stimulus parameters, including frequency resolution, luminance, and the ability to control the phase at the end of the stimulation. The LED stimulator provides a personalized, modular, and affordable option for experimental setups. Based on the Teensy 3.2 board, the stimulator utilizes direct digital synthesis and pulse width modulation techniques to control the LEDs. We validated its performance through four experiments: the first two measured LED light intensities directly, while the last two assessed the stimulator’s impact on EEG recordings. The results demonstrate that the stimulator can deliver a stimulus suitable for generating SSVEPs with the desired frequency and phase resolution. As an open source resource, we provide comprehensive documentation, including all necessary codes and electrical diagrams, which facilitates the system’s replication and adaptation for specific experimental requirements, enhancing its potential for widespread use in the field of neuroscience setups
Multifunctional nano-in-microparticles for targeted lung cancer cells:Synthesis, characterization and efficacy assessment
No full textPublisher Copyright: © 2024 Elsevier LtdNon-small cell lung cancer is the leading cause of cancer-related deaths worldwide. Gemcitabine (GEM) is an effective chemotherapeutic agent for treating this and other cancers. However, the non-specific toxicity of GEM has prompted a search for novel chemotherapeutic strategies. The main objective of this work was to obtain microencapsulated systems loaded with GEM, nanomagnetite and microzeolite in chitosan matrix by spray drying in order to characterise them and test their activity on lung cancer cells. Capsule characterizations showed spherical nano-in-microparticles measuring 1.91 μm on average with a rough surface and characteristic signs of material interaction by TEM and FESEM-EDS. The interaction and loading of nano- and microparticles in the chitosan matrix was evidenced by FT-IR. % E.E. were obtained. greater than 99.00 % in all microencapsules and the release of the GEM was slow and controlled at pH 7.4 and 5.0 up to 24 h. Magnetic mobility was dependent on the concentration of nanomagnetite in the formulation and cell viability was lower than the pure GEM control (1 mg/mL) in both cell lines (A549 and H1299). Nano-in-microencapsulated systems show great potential for inhaled delivery of GEMs for the treatment of non-small cell lung cancer
Reclutamiento de agentes para el centro de gobierno en gobiernos de derecha en Argentina, Uruguay, Chile y Perú: un análisis comparativo
No full textEste trabajo analiza los patrones de reclutamiento de agentes para el Centro de Gobierno (CdG) en gobiernos de derecha en: Argentina, Uruguay, Chile, y Perú. Estudiamos la forma en que se organiza el CdG en cada país y buscamos identificar si existen cambios en los patrones de nominación de ese tipo de agentes a partir de la ideología del gobierno estudiado. Los casos estudiados cuentan con similitudes y diferencias, destacando los distintos niveles de institucionalización del sistema de partidos y los distintos niveles de fuerza electoral de sus partidos de de-recha. Con información de 150 nombramientos en los cuatro países desarrollamos un análisis descriptivo de las principales características de dichos agentes. Encontramos que la institu-cionalización del sistema de partidos tiene un rol relevante en la presencia de independientes y tecnócratas en el CdG, aunque es difícil sacar conclusiones a partir de la dimensión ideológica de los gobiernos
Abordaje del diseño universal para el aprendizaje en el aula de clases con niños y niñas en condición de TEA en primer ciclo de enseñanza básica en cinco establecimientos de la Región Metropolitana
Get PDFPedagogía en Educación Diferencial Advance, Licenciado en EducaciónEl propósito de esta investigación fue analizar el abordaje del diseño universal para el aprendizaje en el aula de clases con niños y niñas en condición de TEA en primer ciclo de enseñanza básica. El DUA es un enfoque didáctico inclusivo que busca adaptar el currículo para atender las necesidades de todos los estudiantes, sin importar sus habilidades o características. Dado que los niños con trastorno del espectro autista enfrentan desafíos específicos en el entorno educativo, la investigación tiene como objetivo proporcionar una comprensión más profunda del DUA aplicado a estos estudiantes. Se busca que los docentes comprendan y apliquen el DUA de manera efectiva, adaptando estrategias pedagógicas para fomentar la participación activa de los estudiantes con TEA en el proceso educativo. En este contexto, el Decreto Exento N°83 de 2015 juega un papel fundamental al promover la diversificación de la enseñanza en la educación parvularia y básica, aprobar criterios y orientaciones de adecuación curricular para estudiantes que lo requieran. Este decreto favorece el aprendizaje y la participación de todos los estudiantes en su diversidad, garantizando un enfoque inclusivo en el sistema educativo. Esta investigación se enfocó en reconocer las fortalezas y debilidades de los docentes al incorporar el DUA en sus planificaciones, especialmente cuando hay estudiantes con TEA en el aula. A través de este estudio, se busca mejorar la comprensión y aplicación del DUA para el abordaje del aprendizaje, así contribuir y lograr una experiencia educativa más inclusiva y efectiva para todos los estudiantes, asegurando así una mayor calidad y equidad en la educación. Palabras claves: Diseño universal de aprendizaje, Trastorno Espectro Autista (TEA), abordaje del aprendizaje, Primer ciclo de Educación Básica (EB), Inclusión.The purpose of this research is to analyze the approach of the Universal Design for Learning in the classroom with children with ASD in the first cycle of elementary school. The DUA is an inclusive didactic approach that seeks to adapt the curriculum to meet the needs of all students, regardless of their abilities or characteristics. Given that children with ASD face specific challenges in the educational environment, the research aims to provide a deeper understanding of SAD as applied to these students. The aim is for teachers to understand and apply the SAD effectively, adapting pedagogical strategies to foster the active participation of students with ASD in the educational process. In this context, the Exempt Decree N°83 of 2015 plays a fundamental role in promoting the diversification of teaching in kindergarten and basic education, approving criteria vi and guidelines for curricular adaptation for students who require it. This decree favors learning and participation of all students in their diversity, guaranteeing an inclusive approach in the educational system. This research focuses on recognizing the strengths and weaknesses of teachers when incorporating the SAD in their planning, especially when there are students with ASD in the classroom. Through this study, we seek to improve the understanding and application of the ULD for the approach to learning, thus contributing and achieving a more inclusive and effective educational experience for all students, ensuring greater quality and equity in education. Key words: Universal Design for Learning, Autism Spectrum Disorder (ASD), approach to learning, first cycle of Basic Education (BE)
Polarity and migration of cranial and cardiac neural crest cells : underlying molecular mechanisms and disease implications
No full textPublisher Copyright: Copyright © 2025 Salinas, Ruano-Rivadeneira, Leal, Caprile, Torrejón and Arriagada.The Neural Crest cells are multipotent progenitor cells formed at the neural plate border that differentiate and give rise to a wide range of cell types and organs. Directional migration of NC cells and their correct positioning at target sites are essential during embryonic development, and defects in these processes results in congenital diseases. The NC migration begins with the epithelial-mesenchymal transition and extracellular matrix remodeling. The main cellular mechanisms that sustain this migration include contact inhibition of locomotion, co-attraction, chemotaxis and mechanical cues from the surrounding environment, all regulated by proteins that orchestrate cell polarity and motility. In this review we highlight the molecular mechanisms involved in neural crest cell migration and polarity, focusing on the role of small GTPases, Heterotrimeric G proteins and planar cell polarity complex. Here, we also discuss different congenital diseases caused by altered NC cell migration
Effective action of the Hořava theory : Cancellation of divergences
No full textPublisher Copyright: © 2024 American Physical Society.We compute the one-loop effective action of the Hořava theory, in its nonprojectable formulation. We take the quantization of the (2+1)-dimensional theory in the Batalin-Fradkin-Vilkovisky formalism, and comment on the extension to the (3+1) case. The second-class constraints and the appropriate gauge-fixing condition are included in the quantization. The ghost fields associated with the second-class constraints can be used to get the integrated form of the effective action, which has the form of a Berezinian. We show that all irregular loops cancel between them in the effective action. The key for the cancellation is the role of the ghosts associated with the second-class constraints. These ghosts form irregular loops that enter in the denominator of the Berezinian, eliminating the irregular loops of the bosonic nonghost sector. Irregular loops produce dangerous divergences; hence their cancellation is an essential step for the consistency of the theory. The cancellation of this kind of divergences is in agreement with the previous analysis done on the (2+1) quantum canonical Lagrangian and its Feynman diagrams
Association between the home-to-healthcare center distance and hearing aid abandonment among older adults
No full textPublisher Copyright: Copyright © 2024 Fuentes-López, Galaz-Mella, Ayala, De la Fuente, Luna-Monsalve, Nieman and Marcotti.Background: Access to audiology services for older adults residing in sparsely populated regions is often limited compared to those in central urban areas. The geographic accessibility to follow-up care, particularly the influence of distance, may contribute to an increased risk of hearing aid abandonment. Objective: To assess the association between the home-to-healthcare-calibration-center distance and hearing aid abandonment among older adults fitted in the Chilean public health system. Methods: 455 patients who received hearing aids from two public hospitals in two regions were considered. Univariate and multivariate Poisson regression models with robust variance estimation were used to analyze the association between the geographical distance and hearing aid abandonment, accounting for confounding effects. Results: Approximately 18% of the sample abandoned the hearing aid, and around 50% reported using the hearing aid every day. A twofold increase in distance between home and the hearing center yielded a 35% (RR = 1.35; 95% CI: 1.04–1.74; p = 0.022) increased risk of hearing aid abandonment. Also, those in the second quintile had a 2.17 times the risk of abandoning the hearing aid compared to the first quintile (up to 2.3 km). Under the assumption that patients reside within the first quintile of distance, a potential reduction of 45% in the incidence of hearing aid abandonment would be observed. The observed risk remained consistent across different statistical models to assess sensitivity. Conclusion: A higher distance between the residence and the healthcare center increases hearing aid abandonment risk. The association may be explained by barriers in purchasing supplies required to maintain the device (batteries, cleaning elements, potential repairs, or maintenance)
Considering planetary health in health guidelines and health technology assessments: a scoping review protocol
No full textPublisher Copyright: © The Author(s) 2024.Abstract Background: This protocol outlines a scoping review with the objective of identifying and exploring planetary health considerations within existing health guidelines and health technology assessments (HTA). The insights gained from this review will serve as a basis for shaping future Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) guidance on planetary health. Methods: We will adhere to the JBI methodology for scoping reviews. We will conduct a comprehensive search and screening of results in all languages across various databases including MEDLINE, EMBASE, CINAHL, Global Health, Health Systems Evidence, Greenfile, and Environmental Issues. Additionally, we will supplement this search with resources such as the GIN library, BIGG database, Epistemonikos, GRADE guidelines repository, GRADEpro Guideline Development Tool Database, MAGICapp, NICE website, WHO websites, and a manual exploration of unpublished relevant documents using Google incognito mode. Two independent reviewers will screen and assess the full texts of identified documents according to the eligibility criteria. The following information from each full text will be extracted: document title; first author's name; publication year; language; document type; document as a guideline or HTA; the topic/discipline; document purpose/study objective; developing/sponsoring organization; the country in which the study/guideline/HTA report was conducted; definition of planetary health or related concept provided; types of planetary health experts engaged; study methods; suggested methods to assess planetary health; use of secondary data on planetary health outcomes; description for use of life cycle assessment; description for assessing the quality of life cycle; population/intended audience; interventions; category; applicable planetary health boundaries; consideration of social justice/global equity; phase of intervention in life cycle related to planetary health addressed; the measure of planetary health impact; impact on biodiversity/land use; one health/animal welfare mention; funding; and conflict of interest. Data analysis will involve a combination of descriptive statistics and directed content analysis, with results presented in a narrative format and displayed in tables and graphs. Discussion: The final review results will be submitted to open-access peer-reviewed journals for publication when they become available. The research findings will also be disseminated at relevant planetary health conferences and workshops
Disbiosis vaginal y su influencia en el desarrollo de parto prematuro. Revisión bibliográfica en América 2014-2024
Get PDFIntroducción: La disbiosis vaginal se define como un desequilibrio en la composición de la microbiota, caracterizado por una disminución de bacterias beneficiosas como Lactobacillus spp. y un aumento de microorganismos patógenos. Este desequilibrio se ha asociado con diversas complicaciones durante el embarazo, especialmente el parto prematuro, que representa un desafío significativo tanto para la salud materna como neonatal. A través de esta tesis, se busca analizar el impacto de la disbiosis vaginal durante el embarazo y cómo puede conducir al parto prematuro, además de identificar métodos de prevención y tratamientos oportunos implementados en la práctica clínica entre 2014 y 2024. Metodología: Se llevó a cabo una revisión sistemática de la literatura utilizando bases de datos académicas como PubMed, Google Scholar y SciELO. Se seleccionaron estudios relevantes publicados entre 2014 y 2024, de acuerdo con los objetivos establecidos, las palabras clave y los criterios de inclusión y exclusión definidos. Resultados: En los estudios seleccionados, se detectó una asociación entre la disbiosis vaginal y un mayor riesgo de parto prematuro. Se observó que la microbiota vaginal de las mujeres embarazadas generalmente presenta una menor diversidad y riqueza bacteriana en comparación con las mujeres no embarazadas, destacando la disminución de especies como Lactobacillus spp., que actúan como protectoras de la microbiota vaginal. Otros estudios analizados sugieren que esta alteración en la microbiota vaginal desencadena una respuesta inflamatoria exacerbada, que conduce al parto prematuro. Además, estrategias preventivas y terapéuticas, como el uso de probióticos y el trasplante de microbiota vaginal, han mostrado un potencial prometedor para restaurar el equilibrio microbiano y reducir el riesgo de complicaciones durante el embarazo. Conclusiones: Los hallazgos de esta investigación destacan la importancia de mantener una microbiota equilibrada durante el embarazo para prevenir complicaciones asociadas con la disbiosis.
Basándose en la investigación realizada, se subraya la necesidad de llevar a cabo más estudios enfocados en esta área para comprender de manera más profunda la disbiosis y su influencia en la salud materna y neonatal en diversas poblaciones.Introduction: Vaginal dysbiosis is defined as an imbalance in the composition of
the microbiota, characterized by a decrease in beneficial bacteria such as Lactobacillus spp., and an increase in pathogenic microorganisms. This imbalance has been associated with various complications during pregnancy, notably preterm birth, which represents a major challenge for both maternal and neonatal health. Through this thesis, we aim to analyze the impact of vaginal dysbiosis during pregnancy and how it can lead to preterm birth, as well as identify prevention methods and timely treatments implemented in clinical practice between 2014 and 2024. Methodology: A systematic literature review was conducted using academic databases such as PubMed, Google Scholar, and SciELO. Relevant studies published between 2014 and 2024 were selected according to the established objectives, keywords, and defined inclusion and exclusion criteria. Results: In the selected studies, an association was detected between vaginal dysbiosis and an increased risk of preterm birth. It was observed that the vaginal microbiota of pregnant women usually presents lower bacterial diversity and richness compared to non-pregnant women, highlighting the
decrease in species such as Lactobacillus spp., which act as protectors of the vaginal microbiota. Other studies analyzed suggest that this alteration in the vaginal microbiota triggers an exacerbated inflammatory response, leading to preterm birth. Additionally, preventive and therapeutic strategies such as probiotics and vaginal microbiota transplantation have shown promising potential to restore microbial balance and reduce the risk of complications during pregnancy. Conclusions: The findings of this research highlight the importance of maintaining a balanced microbiota during pregnancy to prevent complications associated with dysbiosis. Based on the research conducted, there is a need for more studies focused on this area to more deeply understand dysbiosis and its influence on maternal and neonatal health in various populations
Mareo Funcional como una Disfunción Cognitiva Espacial
No full textPublisher Copyright: © 2023 by the authors.(1) Background: Persistent postural-perceptual dizziness (PPPD) is a common chronic dizziness disorder with an unclear pathophysiology. It is hypothesized that PPPD may involve disrupted spatial cognition processes as a core feature. (2) Methods: A cohort of 19 PPPD patients underwent psycho-cognitive testing, including assessments for anxiety, depression, memory, attention, planning, and executive functions, with an emphasis on spatial navigation via a virtual Morris water maze. These patients were compared with 12 healthy controls and 20 individuals with other vestibular disorders but without PPPD. Vestibular function was evaluated using video head impulse testing and vestibular evoked myogenic potentials, while brain magnetic resonance imaging was used to exclude confounding pathology. (3) Results: PPPD patients demonstrated unique impairments in allocentric spatial navigation (as evidenced by the virtual Morris water maze) and in other high-demand visuospatial cognitive tasks that involve executive functions and planning, such as the Towers of London and Trail Making B tests. A factor analysis highlighted spatial navigation and advanced visuospatial functions as being central to PPPD, with a strong correlation to symptom severity. (4) Conclusions: PPPD may broadly impair higher cognitive functions, especially in spatial cognition. We discuss a disruption in the creation of enriched cognitive spatial maps as a possible pathophysiology for PPPD.(1) Antecedentes: El mareo postural-perceptual persistente (MPPP) es un trastorno crónico de mareo común con una fisiopatología poco clara. Se plantea la hipótesis de que el MPPP puede involucrar procesos de cognición espacial alterados como característica central. (2) Métodos: Una cohorte de 19 pacientes con MPPP se sometió a pruebas psico-cognitivas, incluyendo evaluaciones de ansiedad, depresión, memoria, atención, planificación y funciones ejecutivas, con énfasis en la navegación espacial mediante un laberinto de agua de Morris virtual. Estos pacientes se compararon con 12 controles sanos y 20 individuos con otros trastornos vestibulares pero sin MPPP. La función vestibular se evaluó mediante pruebas de impulso cefálico por video y potenciales miogénicos evocados vestibulares, mientras que se utilizó resonancia magnética cerebral para excluir patologías confusoras. (3) Resultados: Los pacientes con MPPP demostraron deficiencias únicas en la navegación espacial alocéntrica (como se evidenció en el laberinto de agua de Morris virtual) y en otras tareas cognitivas visuoespaciales de alta demanda que involucran funciones ejecutivas y planificación, como las pruebas de Torres de Londres y Trail Making B. Un análisis factorial destacó la navegación espacial y las funciones visuoespaciales avanzadas como centrales en el MPPP, con una fuerte correlación con la gravedad de los síntomas. (4) Conclusiones: El MPPP puede afectar ampliamente las funciones cognitivas superiores, especialmente en la cognición espacial. Discutimos una alteración en la creación de mapas espaciales cognitivos enriquecidos como una posible fisiopatología del MPPP