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An agent-based model for semantic search and retrieval in memory is proposed. The model seeks to generate verbal fluency lists with properties similar to those generated by humans in the semantic fluency task. This model is compared to a random walk in a semantic network in its ability to adjust to the results of 141 undergraduate students in the semantic fluency task in eight different outcomes. We found that the agent-based model fits participants' results better than the random walk model. The results were consistent with optimal foraging theories, and the distributions of the total number of words, similarities, and frequency values were similar to those generated by participants. The potential uses of this model as a virtual environment to experiment with the search and retrieval process in semantic memory are discussed.

Over the last few decades, Causal Model Theory (CMT) has become a dominant framework for human causal-based reasoning, including categorization and inference. CMT prescribes how people should reason about probabilistic events in terms of causal models. In typical causal-based categorization experiments, subjects are provided with verbal descriptions of causally linked features, generally including probabilistic information. Another line of research focuses on perceived or experienced causal events, rather than on verbal descriptions. In this work we asked whether effects which are consistent with CMT, and that have been obtained with verbal descriptions, generalize to visually perceived events. In two experiments, we presented subjects with videos of a 3D A→B causal event rather than verbal descriptions. In Exp. 1, we found that subjects who saw the causal event did not show the coherence effect in categorization (i.e., subjects tend to rate the null ¬A¬B event as a category member). However, subjects who did see the null event during training did show the effect. In Exp. 2, we ruled out the possibility that Exp. 1’s results were simply an effect of how frequently events were experienced during training. We conclude that a one-shot perceived causal event is not sufficient for people to show causal-based reasoning as CMT predicts.

This article explores the effects of charter schools on teachers' working conditions in Bogota (Colombia). By employing a semi-experimental approach involving Propensity Score Matching (PSM) and Difference-in-Differences (DID), we find that in the close vicinity (postcode area) of where they are established, charter schools more than double teachers' workload for a comparatively small increase in salaries. In light of a neo-institutional approach, we argue that those advocating for the diversification of school types in Colombia have decoupled the presumed benefits of charter schools' competition from their actual negative effects for teachers. Moreover, we also point out that despite charter schools in Colombia (Bogota) having a not-for-profit status, existing labour flexibilisation policies have exerted isomorphic pressures on them, forcing them to adopt short-term contracts and thus leading to ravaging competition practices among teachers. Overall, we contend that the introduction of charter schools in Colombia (Bogota) has led to a general precarisation of teachers' working conditions.

Fractal‐like geometries applied to biosignal‐electrodes design show great potential for enhancing the signal acquisition of sensing systems. This study reports a novel approach for flexible, silver‐free, and dry fractal‐like electrodes based on Laser‐Induced Graphene (LIG) obtained through laser photothermal processing of a commercial polyimide film. This one‐step mask‐less manufacturing process enables the simple fabrication of natural and optimized fractal‐like shapes inspired by actual snowflake patterns. To ensure a reliable and standardized connection to the measurement unit, the electrodes are equipped with a snap terminal. The electrodes are structurally characterized using various techniques including Scanning Electron Microscopy (SEM), Raman spectroscopy, and X‐ray Photoelectron Spectroscopy (XPS). By benchmarking the performance of these electrodes against Ag/AgCl wet commercial electrodes and LIG electrodes shaped as commercial ones, a heart rate‐monitoring accuracy of over 96.8% is achieved, with high specificity, positive prediction, and sensitivity, surpassing the 95.8% achieved by conventional commercial electrodes. These results demonstrate the efficacy of fractal‐based designs in combination with LIG‐based transduction, offering flexible and cost‐effective electrocardiogram (ECG) electrodes with improved performance compared to traditional wet electrodes. [ABSTRACT FROM AUTHOR]

Cellular migration and contractility are fundamental processes that are regulated by a variety of concerted mechanisms such as cytoskeleton rearrangements, focal adhesion turnover, and Ca2+ oscillations. TRPM4 is a Ca2+-activated non-selective cationic channel (Ca2+-NSCC) that conducts monovalent but not divalent cations. Here, we used a mass spectrometry-based proteomics approach to identify putative TRPM4-associated proteins. Interestingly, the largest group of these proteins has actin cytoskeleton-related functions, and among these nine are specifically annotated as focal adhesion-related proteins. Consistent with these results, we found that TRPM4 localizes to focal adhesions in cells from different cellular lineages. We show that suppression of TRPM4 in MEFs impacts turnover of focal adhesions, serum-induced Ca2+ influx, focal adhesion kinase (FAK) and Rac activities, and results in reduced cellular spreading, migration and contractile behavior. Finally, we demonstrate that the inhibition of TRPM4 activity alters cellular contractility in vivo, affecting cutaneous wound healing. Together, these findings provide the first evidence, to our knowledge, for a TRP channel specifically localized to focal adhesions, where it performs a central role in modulating cellular migration and contractility.

This article explains how after 43 years of unsatisfactory outcomes, the Ministry of Education of Peru (MoE) suddenly ranked at the top of governmental performance tables. To do so, this study relies on implementation and major discussions of policy instrument theories to provide a comprehensive explanation of the reasons underlying the MoE's improvements. Methodologically, this research employs the mixed research methods paradigm. It combines process-tracing and regression analysis. The analyses show that the MoE underwent three major events in its route to achieve policy success. First, the approval of a long-term policy plan (National Educative Plan to 2021); second, the contentious legitimisation of governmental policies against Peru's teachers' union and its eventual defeat; and, third, the recentralisation of historically dispersed control functions in the MoE. The results indicate that upon the occurrence of these reforms, MoE's bureaucrats could gain teachers' legitimacy and eventually achieve complementarity of policy tools. In fact, the multiple regression analysis suggests positive and significant interdependence between the set of tools employed by MoE officers: parents' voluntary monetary contribution to schools (sermon), economic incentives to outperform schools (carrots) and trimestral oversight of schools' performance (sticks). Results also show that MoE's tools are positively associated with satisfactory student-learning outcomes.

Lepidophyma zongolicum is known from only seven specimens (type series) collected in the Sierra Negra of Puebla, Mexico. Here, we report 18 additional records from the Sierra de Zongolica and Sierra de Atoyac in central Veracruz, Mexico. We built a species distribution model that predicts suitable areas for L. zongolicum in the mountains of central Veracruz southward to eastern Puebla and northern Oaxaca. Morphologically our new material is readily assigned to L. zongolicum, but the specimens exhibit variation in the number of dorsal scales, paravertebral scales, dorsal interwhorls, and tail coloration that is previously undocumented for the species. The morphological variation recorded in the specimens allowed us to establish a better diagnosis for the species. Additionally, the new records corroborated the secretive habits and preferential microhabitats of this enigmatic lizard and helped to infer the species potential distribution, showing the species real distribution is likely more extensive than previously known. [ABSTRACT FROM AUTHOR]