Maximizing Indigenous Student Learning in the Mainstream with Language and Culture

In this paper, we explore the importance of being conscious of the needs of indigenous students within the education system in order to increase their learning process and decrease their dropout rates. Specifically, we discuss how Mayan language, culture, and ideologies affect the educational outcome of Mayan students in mainstream classes in Guatemalan schools. From this discussion, we highlight the impact that these factors have on both teacher training and the education of the indigenous student population. A simple “teaching to learn—learning to teach” model is explained which discusses the importance of multilingual and multicultural aspects of teacher training and real-life implications in the indigenous student learning process

Physical parameters of three field RR Lyrae stars

This work was partially supported by DGAPA–Universidad Nacional Autonoma de Mexico through project IN104612.Stromgren uvby - beta photometry of the stars classified as RR Lyrae stars RU Piscium, SS Piscium and TU Ursae Majoris has been used to estimate their iron abundance, temperature, gravity and absolute magnitude. The stability of the pulsating period is discussed. The nature of SS Psc as a RRc or a HADS is addressed. The reddening of each star is estimated from the Stromgren colour indices and reddening sky maps. The results of three approaches to the determination of [Fe/H], T-eff and log(g) are discussed: Fourier light curve decomposition, the Preston Delta S index and the theoretical grids on the (b - y)(o) - c(10) plane.Peer reviewe

Optimising the assessment of cerebral autoregulation from black box models

Cerebral autoregulation (CA) mechanisms maintain blood flow approximately stable despite changes in arterial blood pressure. Mathematical models that characterise this system have been used extensively in the quantitative assessment of function/impairment of CA. Using spontaneous fluctuations in arterial blood pressure (ABP) as input and cerebral blood flow velocity (CBFV) as output, the autoregulatory mechanism can be modelled using linear and non-linear approaches, from which indexes can be extracted to provide an overall assessment of CA. Previous studies have considered a single – or at most a couple of measures, making it difficult to compare the performance of different CA parameters. We compare the performance of established autoregulatory parameters and propose novel measures. The key objective is to identify which model and index can best distinguish between normal and impaired CA. To this end 26 recordings of ABP and CBFV from normocapnia and hypercapnia (which temporarily impairs CA) in 13 healthy adults were analysed. In the absence of a ‘gold’ standard for the study of dynamic CA, lower inter- and intra-subject variability of the parameters in relation to the difference between normo- and hypercapnia were considered as criteria for identifying improved measures of CA. Significantly improved performance compared to some conventional approaches was achieved, with the simplest method emerging as probably the most promising for future studies

A Novel Approach to Multimedia Ontology Engineering for Automated Reasoning over Audiovisual LOD Datasets

Multimedia reasoning, which is suitable for, among others, multimedia content analysis and high-level video scene interpretation, relies on the formal and comprehensive conceptualization of the represented knowledge domain. However, most multimedia ontologies are not exhaustive in terms of role definitions, and do not incorporate complex role inclusions and role interdependencies. In fact, most multimedia ontologies do not have a role box at all, and implement only a basic subset of the available logical constructors. Consequently, their application in multimedia reasoning is limited. To address the above issues, VidOnt, the very first multimedia ontology with SROIQ(D) expressivity and a DL-safe ruleset has been introduced for next-generation multimedia reasoning. In contrast to the common practice, the formal grounding has been set in one of the most expressive description logics, and the ontology validated with industry-leading reasoners, namely HermiT and FaCT++. This paper also presents best practices for developing multimedia ontologies, based on my ontology engineering approach

Explosive first-order transition to synchrony in networked chaotic oscillators

Critical phenomena in complex networks, and the emergence of dynamical abrupt transitions in the macroscopic state of the system are currently a subject of the outmost interest. We report evidence of an explosive phase synchronization in networks of chaotic units. Namely, by means of both extensive simulations of networks made up of chaotic units, and validation with an experiment of electronic circuits in a star configuration, we demonstrate the existence of a first order transition towards synchronization of the phases of the networked units. Our findings constitute the first prove of this kind of synchronization in practice, thus opening the path to its use in real-world applications.Comment: Phys. Rev. Lett. in pres

Comparing Cardiac Dynamics between Neonatal and Adult Rats

Background: Cardiovascular physiology studies have been largely limited to adult models; yet, significant developmental differences exist between the immature and adult heart. The field of pediatric research has largely been limited to immortalized cardiomyocyte cell lines, which lack physiologically relevant action potentials, and primary neonatal myocytes that have a limited life span and lack physiologically relevant automaticity. As a result, our understanding of developmental changes in ion channel expression, t-tubule development, and excitation-contraction coupling have been deduced from 2D simplified cell models. To fully understand cardiac development from neonate to adult, a physiologically-relevant 3D whole heart model is needed to monitor dynamic changes in electrical activity and excitation-contraction coupling. Objective: This study aimed to establish a pediatric research model to monitor developmental changes in electrical activity and excitation-contraction coupling, using both imaging tools and electrocardiograms. Methods/Design: Sprague-Dawley rat hearts (3 days – adult) were excised, the aorta was cannulated, and then the heart was transferred to a temperature-controlled constant pressure Langendorff-perfusion system. The perfusate was supplemented with 10 mM blebbistatin to reduce motion artifacts by mechanically uncoupling electrical and mechanical activity. Calcium (50 mg Rhod2-AM) and voltage (62 mg RH237) sensitive dyes were used to stain the heart, signals were acquired using a sCMOS camera (Andor, Zyla 4.2 Plus; \u3e500fps). Electrocardiograms were monitored continuously (lead II configuration) and analyzed using ecgAUTO. Results/Discussion: Initial results showed that compared to adult cohorts, neonatal rats displayed a longer action potential duration (APD80: adult= 85.9ms, neonatal=95.5ms, p=0.026), and a steeper Tau Fall (adults: 33.8ms, neonatal 69.9ms, p=.012) which are likely associated with delayed Ito expression. Calcium handling was also slower in the neonatal hearts (Cad80: Adults: 128.9ms, neonatal=138.8, p=.004), likely due to immature calcium handling and less robust calcium-induced calcium release. The developing excitation-contraction coupling machinery will be further probed using pharmacological tools to elucidate underlying mechanisms; and the newly developed pediatric model will be used for toxicological screening. Acknowledgements: The authors gratefully acknowledge Daniel McInerney for technical assistance. This work was supported by the National Institutes of Health (R00ES023477, R01HL139472), Children’s Research Institute and Children’s National Heart Institute

Cinco Tensiones en la Implementación de la Ruta de Mejoramiento Institucional en Santander, Colombia

This article presents the results of a qualitative study that identifies five tensions experienced by the teaching directors in the implementation of the Institutional Improvement Route (RMI) in official schools of preschool, basic and secondary education in the department of Santander, Colombia. The methodology is qualitative with a social phenomenological approach. A focus group made up of 15 teaching directors was formed, who, in ten virtual work sessions, identified the following five main tensions: First, between the difficulty of balancing administrative processes and pedagogical ones; second, between managerial and pedagogical discourse; third, between the general guidelines derived from regulations and school autonomy; fourth, between the central level objectives in educational matters and the particularities of school institutions; finally, between technical guidelines and institutional culture. These tensions represent complex challenges for the leadership and management of teaching directors in their work towards the institutional improvement. Additionally, they show the need to redefine the management model of the RMI so that it better adjusts to the regional educational context, considers school autonomy, and recognizes the cultural characteristics of educational communities.Este artículo presenta los resultados de un estudio cualitativo que identifica cinco tensiones experimentadas por los directivos docentes en la implementación de la Ruta de Mejoramiento Institucional (RMI) en establecimientos de educación preescolar, básica y media del departamento de Santander, Colombia. La metodología empleada es cualitativa con enfoque fenomenológico social. Se conformó un grupo focal integrado por 15 directivos docentes, quienes, en diez sesiones de trabajo virtual, identificaron las siguientes cinco tensiones: primero, entre los procesos administrativos y los pedagógicos; segundo, entre el discurso gerencial y el pedagógico; tercero, entre los lineamientos generales de la normatividad y la autonomía escolar; cuarto, entre los objetivos educativos de nivel central y las particularidades de las instituciones escolares; y, quinto, entre los lineamientos técnicos y la cultura institucional. Estas tensiones son retos complejos para el liderazgo y la gestión educativa de los directivos docentes en el mejoramiento institucional. Adicionalmente, evidencian la necesidad de redefinir el modelo gerencial de la RMI para que se ajuste mejor al contexto educativo regional, considere la autonomía escolar y reconozca las características culturales de las comunidades educativas

Dynamics of a ring of three unidirectionally coupled Duffing oscillators with time-dependent damping

We study dynamics of a ring of three unidirectionally coupled double-well Duffing oscillators for three different values of the damping coefficient: fixed dumping, proportional to time, and inversely proportional to time. The dynamics in all cases is analyzed through time series, Fourier and Hilbert transforms, Poincar\'e sections, as well as bifurcation diagrams and Lyapunov exponents with respect to the coupling strength. In the first case, we observe a well-known route from a stable steady state to hyperchaos through Hopf bifurcation and a series of torus bifurcations, as the coupling strength is increased. In the second case, the system is highly dissipative and converges into one of stable equilibria. Finally, in the third case, transient toroidal hyperchaos takes place

Nanomedicine against biofilm infections: A roadmap of challenges and limitations

Microbial biofilms are complex three-dimensional structures where sessile microbes are embedded in a polymeric extracellular matrix. Their resistance toward the host immune system as well as to a diverse range of antimicrobial treatments poses a serious health and development threat, being in the top 10 global public health threats declared by the World Health Organization. In an effort to combat biofilm-related microbial infections, several strategies have been developed to independently eliminate biofilms or to complement conventional antibiotic therapies. However, their limitations leave room for other treatment alternatives, where the application of nanotechnology to biofilm eradication has gained significant relevance in recent years. Their small size, penetration efficiency, and the design flexibility that they present makes them a promising alternative for biofilm infection treatment, although they also present set-backs. This review aims to describe the main possibilities and limitations of nanomedicine against biofilms, while covering the main aspects of biofilm formation and study, and the current therapies for biofilm treatment. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials Toxicology and Regulatory Issues in Nanomedicine > Regulatory and Policy Issues in Nanomedicine