fMRI lag structure during waking up from early sleep stages.

The brain mechanisms by which we transition from sleep to a conscious state remain largely unknown in humans, partly because of methodological challenges. Here we study a pre-existing dataset of waking up participants originally designed for a study of dreaming (Horikawa, Tamaki, Miyawaki, & Kamitani, 2013) and suggest that suddenly awakening from early sleep stages results from a two-stage process that involves a sequence of cortical and subcortical brain activity. First, subcortical and sensorimotor structures seem to be recruited before most cortical regions, followed by fast, ignition-like whole-brain activation-with frontal regions engaging a little after the rest of the brain. Second, a comparably slower and possibly mirror-reversed stage might take place, with cortical regions activating before subcortical structures and the cerebellum. This pattern of activation points to a key role of subcortical structures for the initiation and maintenance of conscious states.

Simple Sonochemical Method to Optimize the Heating Efficiency of Magnetic Nanoparticles for Magnetic Fluid Hyperthermia.

We developed a fast, single-step sonochemical strategy for the green manufacturing of magnetite (Fe3O4) magnetic nanoparticles (MNPs), using iron sulfate (FeSO4) as the sole source of iron and sodium hydroxide (Na(OH)) as the reducing agent in an aqueous medium. The designed methodology reduces the environmental impact of toxic chemical compounds and minimizes the infrastructure requirements and reaction times down to minutes. The Na(OH) concentration has been varied to optimize the final size and magnetic properties of the MNPs and to minimize the amount of corrosive byproducts of the reaction. The change in the starting FeSO4 concentration (from 5.4 to 43.1 mM) changed the particle sizes from (20 ± 3) to (58 ± 8) nm. These magnetite MNPs are promising for biomedical applications due to their negative surface charge, good heating properties (≈324 ± 2 W/g), and low cytotoxic effects. These results indicate the potential of this controlled, easy, and rapid ultrasonic irradiation method to prepare nanomaterials with enhanced properties and good potential for use as magnetic hyperthermia agents.

Representaciones sociales sobre la formación inicial docente: evaluación diagnóstica a estudiantes que ingresan a carreras pedagógicas en dos universidades chilenas / Social Representations about Initial Teacher Training: Diagnostic Assessment of Students who Enroll in Pedagogical Programs at two Chilean Universities

Resumen Este estudio es de tipo descriptivo e interpretativo y da cuenta de los resultados de las representaciones sociales sobre la profesión docente que autorreportan alumnos que ingresan a la formación inicial de profesores en dos instituciones chilenas de educación superior estatales; una de la región de Ñuble y la otra de la Región de Los Lagos. Este estudio surge a partir de la actualización del sistema nacional de aseguramiento de la calidad de la educación, en donde se establece la obligatoriedad de aplicar test de evaluación diagnóstica. Para tal efecto la población estuvo conformada por 834 estudiantes de la cohorte 2018, pertenecientes a 15 carreras de Pedagogía en dos universidades del país. Se aplicó un instrumento escala tipo Likert, validado en una población similar en el año 2017. Para realizar el análisis de la información, se aplicaron métodos descriptivos numéricos e inferenciales. En sus principales conclusiones, se devela representaciones sociales comunes en dimensiones sobre vocación, ejercicio de la profesión, prestigio e imagen social del profesorado, independiente del sexo, de lo que se desprende que los sujetos evaluados conforman una identidad profesional claramente modelada antes de comenzar su formación inicial docente.

Abstract: This descriptive and interpretative study accounts for results of social representations regarding the teaching pro- fession which students of initial teacher training report in two Chilean public institutions of Higher Education, from Ñuble and Los Lagos regions. This study arises from the updating of the National Educational Quality Assurance System, which establishes the obligation to apply a diagnostic test. To this end, the population was composed of 834 students from the 2018 cohort of 15 pedagogical programs from two national universities. A Likert-like scale instrument was applied, it was validated in a similar population in 2017. Numerical descriptive and inferential me- thods were applied to analyze the information. Generally concluding, common social representations are revealed about vocation, professional performance, prestige and social image of teachers regardless of sex; it suggests that the evaluated subjects shape a clearly modelled professional identity before starting their Initial Teacher Training.