A new approach in treating neonatal hypoxic-ischaemic and infection sensitised hypoxic-ischaemic brain damage

Neonatal hypoxia-ischemia (HI) brain injury is a leading cause of death, with high morbidity. The clinical manifestation is more severe in cases of pre-exposure to bacterial infections, and no effective treatments are currently available for infection-sensitised HI damage. We hypothesised that two compounds would have a therapeutic activity in HI brain injury: AnxV, a widely used apoptotic marker that is suggested to interact with bacterial membranes, and curcumin, a plant-derived compound with anti-inflammatory, antioxidative and anti-apoptotic properties. AnxV mechanism of action was evaluated through biophysics membrane interaction techniques and lipid binding assays, using different components of bacterial membranes. AnxV displayed cooperative kinetics in binding to LipidA, but not to LPS. Following, AnxV was then used as a treatment in a mouse model for neonatal HI and infection-sensitised HI, showing neuroprotective effects in normal HI, and partial protection in infection-sensitised HI. Importantly, infrared labelled AnxV was observed to cross the blood-brain barrier and accumulate at the site of injury. The intraperitoneal administration of curcumin in DMSO solution to HI animals showed clear neuroprotection in a dose-dependent fashion. However, the toxicity of DMSO and the poor bioavailability of curcumin necessitated further optimisation to make the product suitable for clinical use. We synthesised curcumin-loaded nanoparticles that showed a much slower rate of release in vitro than what was observed for free curcumin. In neonatal HI, the intranasal administration of the curcumin nanoparticles resulted in reduced astrogliosis and tissue loss. Finally, we focused on combining the targeting ability of AnxV with curcumin neuroprotection to maximise the therapeutic benefits. For this purpose, AnxV-functionalised curcumin-loaded nanoparticles were generated and future studies should focus on optimising this formulation. In conclusion, both AnxV and curcumin were neuroprotective in neonatal HI and combining the two treatments could generate beneficial effects to an even greater level than was achieved with either compound individually

Cuestionario de riesgo de deserción universitaria (CDUe) basado en el modelo ecológico

Antecedentes. La Teoría Ecológica del desarrollo humano permite comprender la deserción universitaria como fenómeno multidimensional y multivariado; pero los cuestionarios existentes no han sido estructurados ni validados bajo esta perspectiva teórica. Objetivo. Construir y validar un cuestionario para evaluar el riesgo percibido de deserción en estudiantes universitarios, desde la percepción de las incongruencias en los procesos de interacción del estudiante y sus entornos ecológicos próximos y distales que generan incumplimiento de las expectativas de formación profesional. Metodología. Estudio psicométrico con enfoque empírico-analítico, de tipo cuantitativo, metodología descriptiva, con medidas transversales individuales. Se usó muestreo probabilístico estratificado para seleccionar 729 estudiantes, de dos universidades colombianas. Resultados. La estructura factorial del cuestionario explica el 38% de la varianza, con 49 ítems (α>,68; w>,67), agrupados en cinco escalas (nivel micro: autoeficacia y decisión vocacional; nivel meso: redes de apoyo funcionales y disfuncionales; nivel macro: estructura de soporte curricular e inserción laboral). La escala unidimensional de inserción laboral para estudiantes de último año de carrera, agrupó 14 ítems (α>,8; w>,8) y explica el 22,45% de la varianza. Las escalas autoeficacia, redes de apoyo y soporte curricular poseen buenos niveles de sensibilidad y la escala decisión vocacional posee alto nivel de especificidad. Conclusiones. Existe evidencia de validez de constructo y convergente y de fiabilidad psicométrica del cuestionario para detectar alertas tempranas de deserción en estudiantes desde la teoría ecológica. El cuestionario es útil para seguimiento longitudinal; este modelo multidimensional asocia el análisis del tiempo, el género y la universidad (público o privado)

Improving Learning and Study Strategies in Undergraduate Medical Students: A Pre-Post Study

We aimed to describe the impact of a structured interventional program to improve learning and study skills in undergraduate medical students from a Latin American medical school. The interventional program’s design was based on diagnostic/prescriptive assessment test scores measuring ten scales. The program consisted of five tailored workshops. The cohort studied consisted of 81 third-year medical students. The outcome variable was the difference between “pre” and “post” test scores. The unadjusted score percentiles were used to compare improvement in learning and study skills. In addition, a sensitivity analysis was conducted to assess variation in the mean difference of the test scores by the number of workshops attended. The response rate was 100% (81/81) for the pre test and ~77% (62/81) for the post test. After the interventional program, nine out of ten scales showed statistical improvement, except for the scale of motivation. The scales with the highest and lowest percent change improvement were time management (66%, p-value: <0.001) and motivation (14.9%, p-value: 0.06). The students who attended more workshops obtained a higher percent change improvement in the post test. These findings suggest that through a well-designed interventional program, it is possible to improve learning and study skills among medical students

Improving Learning and Study Strategies in Undergraduate Medical Students: A Pre-Post Study

We aimed to describe the impact of a structured interventional program to improve learning and study skills in undergraduate medical students from a Latin American medical school. The interventional program’s design was based on diagnostic/prescriptive assessment test scores measuring ten scales. The program consisted of five tailored workshops. The cohort studied consisted of 81 third-year medical students. The outcome variable was the difference between “pre” and “post” test scores. The unadjusted score percentiles were used to compare improvement in learning and study skills. In addition, a sensitivity analysis was conducted to assess variation in the mean difference of the test scores by the number of workshops attended. The response rate was 100% (81/81) for the pre test and ~77% (62/81) for the post test. After the interventional program, nine out of ten scales showed statistical improvement, except for the scale of motivation. The scales with the highest and lowest percent change improvement were time management (66%, p-value: p-value: 0.06). The students who attended more workshops obtained a higher percent change improvement in the post test. These findings suggest that through a well-designed interventional program, it is possible to improve learning and study skills among medical students

Laser Shock Peening on a 6056-T4 Aluminium Alloy for Airframe Applications

Laser Shock Peening (LSP) is a material enhancement process used to introduce compressive residual stresses in metallic components. This investigation explored the effects of different combinations of LSP parameters, such as irradiance (GW/cm2) and laser pulse density (spots/mm2), on 3.2 mm thick AA6056-T4 samples, for integral airframe applications. The most significant effects that are introduced by LSP without a protective coating include residual stress and surface roughness, since each laser pulse vaporizes the surface layer of the target. Each of these effects was quantified, whereby residual stress analysis was performed using X-ray diffraction with synchrotron radiation. A series of fully reversed bending fatigue tests was conducted, in order to evaluate fatigue performance enhancements with the aim of identifying LSP parameter influence. Improvement in fatigue life was demonstrated, and failure of samples at the boundary of the LSP treatment was attributed to a balancing tensile residual stress

Sistemas agroalimentarios localizados : análisis y políticas públicas

El lector interesado en los estudios sobre el territorio podrá aproximarse en las páginas de esta obra colectiva por medio de diversas escalas. La primera de ellas: los Sistemas Agroalimentarios Localizados (SIAL), y en su intersección disciplinaria, con la gobernanza y la acción pública en el nivel teórico y conceptual, así como diversos estudios de caso en América Latina. La segunda, se relaciona con la valoración de las formas de proximidad que están presentes en los sistemas agroalimentarios periurbanos y las relaciones de confianza que establecen productores y consumidores por medio de las cadenas cortas agroalimentarias, ligadas a la conservación y valoración de los productos de la agrodiversidad. La siguiente escala de análisis destaca la relación de los SIAL con las políticas públicas y las formas de gobernanza, que se construyen en los territorios. Los capítulos presentan avances y/o resultados de investigaciones cualitativas, discusiones en torno a los tipos de gobernanza y sus alcances, las diferencias e implicaciones de la gobernanza territorial e importancia que tiene para el territorio esa construcción política y social. Paralelamente, los análisis alertan sobre procesos de exclusión social cuando un grupo logra obtener ventajas territoriales no generalizadas al sistema agroalimentario local y donde la gestión de políticas públicas es imprescindible a fin de regular y favorecer la inclusión. En este sentido, se observa como la acción colectiva puede llegar a ocupar un papel protagónico en la construcción de gobernanza territorial. En una cuarta escala de análisis se estudia la presencia dominante en el mercado de las corporaciones globales y sus efectos en los territorios, por la corrupción en las relaciones gobierno-empresa, que anulan o subordinan las posibilidades de un desarrollo territorial en los ámbitos: económico, ambiental, alimentario y cultural, así como respuestas de innovación social.Trabajo realizado con el apoyo del Programa UNAM DGAPA-PAPIIT IN303117Libro