Tránsito entre representaciones en matemáticas ¿pensamiento global o local?

Este trabajo pretende dar a conocer el avance, que hasta el momento se ha logrado, en la línea de investigación: “Visualización y pensamiento global en Matemáticas”, la cual persigue, a partir de la Teoría de Representaciones Semióticas de Duval, la caracterización del estilo de pensamiento global y local, de estudiantes de nivel medio superior y superior y de sus profesores. En particular reporto los resultados preliminares encontrados hasta el momento con estudiantes de primeros semestres de licenciatura al abordar un problema de precálculo, contrastado con desempeños en ajedrez para interpretar aspectos semejantes en cuanto a la forma local o global de pensar un problema viendo sus registros que lleven a resultados que pudieran servir en la mejora de la enseñanza de algunos temas de matemáticas

Relationship Amongst Technology Use, Work Overload, and Psychological Detachment from Work

Permanent connection to the work world as a result of new technologies raises the possibility of workday extensions and excessive workloads. The present study addresses the relationship between technology and psychological detachment from work resulting from work overload. Participants were 313 professionals from the health sector who responded to three instruments used in similar studies. Through PLS-SEM, regression and dependence analyses were developed, and through the bootstrapping method, significance of factor loadings, path coefficients and variances were examined. Results of the study corroborate a negative effect of technology use on psychological detachment from work and a positive correlation between technology and work overload. Additionally, there is a significant indirect effect of technology on psychological detachment from work as a result of work overload. Findings extend the literature related to the stressor-detachment model, and support the idea that workers who are often connected to their jobs by technological tools are less likely to reach adequate psychological detachment levels. Implications for the academic community and practitioners are discusse

Inflammation and impaired adipogenesis in human white adipose tissue

This thesis aimed to study inflammation and adipogenesis capacity in human subcutaneous white adipose tissue with respect to the development of obesity and associated comorbidities, including insulin resistance. Study I showed that the transcription factor, MAFB, was associated with increased adiposity and involved in regulation of TNFα-mediated inflammatory response, yet did not seem to directly influence adipogenesis or metabolism in human adipocytes. MAFB expression was upregulated during adipogenesis, and knocking down MAFB mRNA led to reduced TNFα-mediated inflammation. However, MAFB was highly expressed in white adipose tissue (WAT) macrophages, which most likely explains its association with BMI and metabolic syndrome. Study II identified increased fat cell size as a hallmark of non-obese type 2 diabetic individuals. This hypertrophic status was associated with insulin resistance, inflammation and adipose tissue lipolysis indicating fat cell size to be a marker of pathogenesis. Relative amount of pro-inflammatory macrophages (M1/M2 ratio) correlated positively with fat cell size, lipolysis and TNFα secretion. In addition, early and late adipogenesis markers correlated negatively with fat cell size, suggesting impaired production of new fat cells in WAT hypertrophy. Study III revealed that human adipocyte progenitors from subcutaneous WAT of healthy individuals consist of a single homogenous cell population. Furthermore, multiple macrophage subtypes were identified. We could not exclude that adipose progenitor subtypes might exist. However, any subtypes were not detectable by the methods employed in this study. Both findings are significant and warrant further investigation. To conclude the finding in this thesis, we defined a role for MAFB in adipose tissue inflammation, which can possibly serve as a biomarker of insulin resistance and inflammation in WAT. Fat cell size seemed to be the best predictor for insulin resistance in non-obese individuals and this appeared likely connected to impaired adipogenic capacity of WAT. However, a search for different progenitor populations bearing varied abilities to become fat cells through the use of a single-cell RNA sequencing technique was not successful as only one major population of progenitors in healthy WAT was found. This demonstrated a need for further studies in larger cohorts of individuals characterized by different metabolic statuses

QEEG Studies of the Acute Effects of the Visionary Tryptamine DMT

Recent brain imaging studies in Psychedelic Brain Science are breaking new ground in our understanding of neurological substrate of biological consciousness in humans. The emerging field of inner experience and neuroscience is particularly well suited to the reexamination of the actions of psychedelics on subjective conscious experience. This approach is best understood as neurophenomenology. My work over the last few years has focused on the EEG correlates of the visionary tryptamine DMT action.  I believe the researcher must also have the drug experience as part of the experimental protocol, in order to fully understand the richness of the phenomenon. The objective of this exploratory research was to examine the QEEG correlates of the psychoactive smoked inhalation of exogenous DMT action.  Known as a potent visionary tryptamine, DMT  is ubiquitous in nature and has also been localized in the brain and peripheral tissues of mammals, including humans. The exact function of this endogenous DMT is the subject of ongoing neuropharmacological  research. Three sources of DMT were tested: high purity synthetic 5-MeO- DMT, Bufo 5-MeO-DMT (an extract from the Sonoran desert toad venom, Bufo alvarius), and N,N- DMT from a natural extract of the Acacia tree Mimosa hostilis  root bark. The DMT was delivered by smoked inhalation (vaporization). The rapid onset (10-20 sec), short acting  (5-15 min.), and reversible nature of the effects made such a QEEG study feasible. DMT dosage was adjusted to elicit an effective psychedelic experience (ca. 20-30 mg for N,N-DMT; 2-5 mg for synthetic 5-MeO-DMT, and 30-40 mg for the Bufo 5-MeO-DMT material). Healthy volunteers (age 25-60; N=15 men, N=8 women) were tested.  The protocol consisted of:  5-10 min. baseline control (resting eyes closed) was first acquired, followed by the DMT test condition, usually lasting 5-15 min. When subjects recovered from the DMT induced altered state, a report of their subjective experience was recorded on video and a post recovery  EEG reading was made typically at 15-30 min. A statistical comparison (paired t-tests, correlated samples) of absolute power values for all EEG bands  between baseline vs. DMT tests and post recovery conditions was carried out for all subjects. The DMT- induced profound alterations in consciousness  were tracked with the shifts in the QEEG metrics analysed. The time course and intensity of the subjective experience correlated with the magnitude of the observed EEG effects. The most consistent effect was a robust suppression of Alpha, obtained for both N,N-DMT and 5-MeO-DMT (Alpha decreased ave. 72%, N=6). During recovery, some subjects showed Alpha rebound increased power at 15-25 min. post DMT (ave. 43% incr.,