Conexiones matemáticas asociadas a las ecuaciones diferenciales ordinarias de primer orden

En este artículo, se muestran las conexiones matemáticas que establecen estudiantes universitarios al resolver tareas que involucran Ecuaciones Diferenciales Ordinarias de primer orden. Consideramos las conexiones matemáticas como un proceso mediante el cual una persona relaciona una o más ideas, conceptos, representaciones, teoremas o significados entre sí, con los de otras disciplinas o con situaciones de la vida real. Se utilizó la entrevista basada en tareas para la recolección de datos, que fueron analizados con el método de análisis temático. Los resultados indican el uso de siete tipos de conexiones matemáticas: representaciones diferentes, procedimental, significado, característica, parte-todo, implicación y reversibilidad. No obstante, se observó que un desempeño académico alto no es indicador de que las conexiones emerjan adecuadamente en la resolución de tareas

Conexões matemáticas associadas a equacões diferenciais ordinárias de primeira ordem

This paper shows the mathematical connections that university students make when solving tasks involving first-order Ordinary Differential Equations. We consider mathematical connections as a process by which a person relates one or more ideas, concepts, representations, theorems, or meanings to each other, to those in other disciplines or to real-life situations. For data collection, task-based interviews were used, which were analyzed with the Thematic Analysis method. The results indicate the use of seven types of mathematical connections: different representations, procedural, meaning, characteristic, part-whole, implication and reversibility. However, it was observed that a high academic performance is not an indicator that the connections emerge adequately in the resolution of tasks.En este artículo, se muestran las conexiones matemáticas que establecen estudiantes universitarios al resolver tareas que involucran Ecuaciones Diferenciales Ordinarias de primer orden. Consideramos las conexiones matemáticas como un proceso mediante el cual una persona relaciona una o más ideas, conceptos, representaciones, teoremas o significados entre sí, con los de otras disciplinas o con situaciones de la vida real. Se utilizó la entrevista basada en tareas para la recolección de datos, que fueron analizados con el método de análisis temático. Los resultados indican el uso de siete tipos de conexiones matemáticas: representaciones diferentes, procedimental, significado, característica, parte-todo, implicación y reversibilidad. No obstante, se observó que un desempeño académico alto no es indicador de que las conexiones emerjan adecuadamente en la resolución de tareas.Neste artigo, se mostra as conexões matemáticas que fazem os estudantes universitários ao resolver tarefas que incluem as Equações Diferenciais Ordinárias de primeira ordem. Consideramos as conexões matemáticas como um processo mediante o qual uma pessoa relaciona uma ou mais ideias, conceitos, representações, teoremas ou significados entre si, com os de outras disciplinas ou com situações da vida real. Para a coleta de dados foi utilizado a entrevista baseada em tarefas, as quais foram analisadas com o método de análise temático. Os resultados indicam o uso de sete tipos de conexões matemáticas: representações diferentes, procedimental, significado, característica, parte-todo, implicação e reversibilidade. Contudo, foi observado que um desempenho acadêmico alto não é indicador de que as conexões emergem adequadamente na resolução de tarefas

Evaluación de material particulado PM10 y PM2.5 en la universidad libre seccional socorro, barrios el portal de Saravita y el primero de mayo

El presente trabajo de grado evaluó las concentraciones de material particulado PM10 y PM2.5 que se presenta en la Universidad Libre Seccional Socorro, teniendo como base la investigación V de (Cordero & Hernández, 2019) donde se tuvieron en cuenta los sitios de monitoreo conocidos como focos de contaminación, adicionalmente para este estudio se tuvieron presentes los barrios aledaños que son el Portal de Saravita y el Primero de Mayo para determinar si el curso del viento influía, para ello se realizaron monitoreos durante los meses de octubre y noviembre del 2019 con los equipos IGERESS detector WP6912 y el The SidePak™ Personal Aerosol Monitor AM520. Antes de cada toma de datos en los sitios de monitoreo se realizaba la calibración de los equipos utilizados durante la investigación, esta toma de datos se hacía cuatro días de la semana de martes a viernes en los barrios aledaños desde las 8:30 am hasta las 9:46 am y en la Universidad desde las 3:00 pm hasta las 5:22 pm en los meses de octubre y noviembre del año 2019. Por otra parte, se tuvieron en cuenta las condiciones meteorológicas suministradas por la estación Campus Majavita donde diariamente los datos fueron tabulados en la herramienta ofimática excel para poder analizar la relación existente entre las concentraciones de material particulado con respecto a las condiciones meteorológicas en los sitios de monitoreo. También, se tuvieron en cuenta los datos en la investigación V (Cordero & Hernández, 2019) para la comparación de los monitoreos realizados con el equipo IGERESS en la presente investigación y de esta forma determinar si se presentaba fluctuaciones en los datos a través de los meses, posteriormente fueron analizados los valores obtenidos con el equipo SidePak™ para evaluar las concentraciones de material particulado de la Universidad y los barrios aledaños. Los datos fueron estudiados por medio de la estadística descriptiva y teniendo en cuenta la tabla No 6 “puntos de corte ICA” de la resolución 2254 del 2017 para de esta manera conocer que sitios superaban esta resolución. Además, por medio de consulta bibliográfica se identificaron bioindicadores existentes para contaminantes PM10 y PM2.5 dentro de la Universidad. Por último, se elaboró un plan de control y mitigación para los sitios que excedieron la resolución. Para analizar los datos se halló el promedio aritmético de las concentraciones de material particulado de cada sitio, se encontró que algunos superan los niveles máximos permisibles de la resolución 2254 de 2017 donde la planta torrefactora de café es la que presenta mayor concentración para los contaminantes PM10 con 0,207 mg/m3 y PM2.5 con 0,161 mg/m3. Por lo que es recomendable tomar acciones preventivas, como es la implementación de medidas de protección personal.Universidad Libre Seccional Socorro - Facultad de ciencias económicas administrativas y contablesThe present degree work evaluated the concentrations of particulate material PM10 and PM2.5 that is presented at the Universidad Libre Seccional Socorro, based on the research V of (Cordero & Hernández, 2019) where the monitoring sites known as sources of contamination were taken into account, additionally for this study the neighboring neighborhoods that are the Portal de Saravita and the Primero de Mayo were taken into account to determine if the course of the wind had an influence, for this, monitoring was carried out during the months of October and November 2019 with the IGERESS detector WP6912 and The SidePak ™ Personal Aerosol Monitor AM520. Before each data collection at the monitoring sites, the calibration of the equipment used during the investigation was carried out, this data collection was done four days a week from Tuesday to Friday in the surrounding neighborhoods from 8:30 a.m. to 10:00 p.m. 9:46 am and at the University from 3:00 pm to 5:22 pm in the months of October and November of the year 2019. On the other hand, the meteorological conditions provided by the Campus Majavita station were taken into account, where daily the data were tabulated in the excel office automation tool in order to be able to analyze the relationship between the concentrations of particulate material with respect to the meteorological conditions at the sites of monitoring. Also, the data in research V (Cordero & Hernández, 2019) were taken into account for the comparison of the monitoring carried out with the IGERESS team in the present investigation and in this way to determine if there were fluctuations in the data through the months, later the values obtained with the SidePak ™ equipment were analyzed to evaluate the concentrations of particulate material in the University and the surrounding neighborhoods. The data were studied through descriptive statistics and taking into account Table No. 6 “ICA cut-off points” of resolution 2254 of 2017 in order to know which sites exceeded this resolution. In addition, by means of bibliographic consultation, existing bioindicators for pollutants PM10 and PM2.5 were identified within the University. Finally, a control and mitigation plan was developed for the sites that exceeded the resolution. To analyze the data, the arithmetic average of the concentrations of particulate material of each site was found, it was found that some exceed the maximum permissible levels of resolution 2254 of 2017 where the coffee roasting plant is the one with the highest concentration for PM10 pollutants. with 0.207 mg / m3 and PM2.5 with 0.161 mg / m3. Therefore, it is advisable to take preventive actions, such as the implementation of personal protection measures

Phosphorylation-mediated unfolding of a KH domain regulates KSRP localization via 14-3-3 binding

The AU-rich element (ARE)-mediated mRNA-degradation activity of the RNA binding K-homology splicing regulator protein (KSRP) is regulated by phosphorylation of a serine within its N-terminal KH domain (KH1). In the cell, phosphorylation promotes the interaction of KSRP and 14-3-3ζ protein and impairs the ability of KSRP to promote the degradation of its RNA targets. Here we examine the molecular details of this mechanism. We report that phosphorylation leads to the unfolding of the structurally atypical and unstable KH1, creating a site for 14-3-3ζ binding. Using this site, 14-3-3ζ discriminates between phosphorylated and unphosphorylated KH1, driving the nuclear localization of KSRP. 14-3-3ζ –KH1 interaction regulates the mRNA-decay activity of KSRP by sequestering the protein in a separate functional pool. This study demonstrates how an mRNA-degradation pathway is connected to extracellular signaling networks through the reversible unfolding of a protein domain.European Molecular Biology Organization 240-2005Italian CIPE-200

Physiology and Pathology of Innate Immune Response Against Pathogens

Pathogen infections are recognized by the immune system, which consists of two types of responses: an innate immune response and an antigen-specific adaptive immune response. The innate response is characterized by being the first line of defense that occurs rapidly in which leukocytes such as neutrophils, monocytes, macrophages, eosinophils, mast cells, dendritic cells, etc., are involved. These cells recognize the pathogen-associated molecular patterns (PAMPs), which have been evolutionarily conserved by the diversity of microorganisms that infect humans. Recognition of these pathogen-associated molecular patterns occurs through pattern recognition receptors such as Toll-like receptors and some other intracellular receptors such as nucleotide oligomerization domain (NOD), with the aim of amplifying the inflammation and activating the adaptive cellular immune response, through the antigenic presentation. In the present chapter, we will review the importance of the main components involved in the innate immune response, such as different cell types, inflammatory response, soluble immune mediators and effector mechanisms exerted by the immune response against bacteria, viruses, fungi, and parasites; all with the purpose of eliminating them and eradicating the infection of the host

Impact of neurodegenerative diseases on human adult hippocampal neurogenesis

Disrupted hippocampal performance underlies psychiatric comorbidities and cognitive impairments in patients with neurodegenerative disorders. To understand the contribution of adult hippocampal neurogenesis (AHN) to amyotrophic lateral sclerosis, Huntington's disease, Parkinson's disease, dementia with Lewy bodies, and frontotemporal dementia, we studied postmortem human samples. We found that adult-born dentate granule cells showed abnormal morphological development and changes in the expression of differentiation markers. The ratio of quiescent to proliferating hippocampal neural stem cells shifted, and the homeostasis of the neurogenic niche was altered. Aging and neurodegenerative diseases reduced the phagocytic capacity of microglia, triggered astrogliosis, and altered the microvasculature of the dentate gyrus. Thus, enhanced vulnerability of AHN to neurodegeneration might underlie hippocampal dysfunction during physiological and pathological aging in humans.Fil: Terreros Roncal, J.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Moreno Jiménez, E.P.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Flor García, M.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Rodríguez Moreno, C.B.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Trinchero, Mariela Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Cafini, F.. Universidad Europea de Madrid; EspañaFil: Rábano, A.. No especifíca;Fil: Llorens Martín, M.. Universidad Autónoma de Madrid; Españ

Modelo a escala de un sistema de riego automatizado, alimentado con energía solar fotovoltaica: nueva perspectiva para el desarrollo agroindustrial colombiano

En este artículo se describe el procedimiento seguido del diseño e implementación de un modelo a escala del sistema de riego automatizado alimentado con energía solar foto-voltaica, diseñado para una finca ubicada en una zona cálida de Colombia. Este modelo fue instalado en la Facultad Tecnológica de la Universidad Distrital Francisco José de Caldas, con el propósito de comprobar su funcionamiento desde las condiciones climáticas de Bogotá. El sistema de control se plantea con base en la plataforma de programación y automatización Arduino, donde se miden, integran y procesan señales analógicas que conforman el sistema automatizado, y se responde a las necesidades de riego en la finca seleccionada, o de cualquier otra del sector agrícola, donde el abastecimiento de energía eléctrica es escaso, pero donde se dispone de recursos hídrico y solar suficientes para suplir las necesidades, tal como sucede en este caso. Es así como el sistema suple y regula necesidade

GSK-3β orchestrates the inhibitory innervation of adult-born dentate granule cells in vivo

Adult hippocampal neurogenesis enhances brain plasticity and contributes to the cognitive reserve during aging. Adult hippocampal neurogenesis is impaired in neurological disorders, yet the molecular mechanisms regulating the maturation and synaptic integration of new neurons have not been fully elucidated. GABA is a master regulator of adult and developmental neurogenesis. Here we engineered a novel retrovirus encoding the fusion protein Gephyrin:GFP to longitudinally study the formation and maturation of inhibitory synapses during adult hippocampal neurogenesis in vivo. Our data reveal the early assembly of inhibitory postsynaptic densities at 1 week of cell age. Glycogen synthase kinase 3 Beta (GSK-3β) emerges as a key regulator of inhibitory synapse formation and maturation during adult hippocampal neurogenesis. GSK-3β-overexpressing newborn neurons show an increased number and altered size of Gephyrin+ postsynaptic clusters, enhanced miniature inhibitory postsynaptic currents, shorter and distanced axon initial segments, reduced synaptic output at the CA3 and CA2 hippocampal regions, and impaired pattern separation. Moreover, GSK-3β overexpression triggers a depletion of Parvalbumin+ interneuron perineuronal nets. These alterations might be relevant in the context of neurological diseases in which the activity of GSK-3β is dysregulatedPID2020-113007RB-I00, SAF-2017-82185-R, PID2020-112824GB-10

Methods to study adult hippocampal neurogenesis in humans and across the phylogeny

The hippocampus hosts the continuous addition of new neurons throughout life—a phenomenon named adult hippocampal neurogenesis (AHN). Here we revisit the occurrence of AHN in more than 110 mammalian species, including humans, and discuss the further validation of these data by single-cell RNAseq and other alternative techniques. In this regard, our recent studies have addressed the long-standing controversy in the field, namely whether cells positive for AHN markers are present in the adult human dentate gyrus (DG). Here we review how we developed a tightly controlled methodology, based on the use of high-quality brain samples (characterized by short postmortem delays and ≤24 h of fixation in freshly prepared 4% paraformaldehyde), to address human AHN. We review that the detection of AHN markers in samples fixed for 24 h required mild antigen retrieval and chemical elimination of autofluorescence. However, these steps were not necessary for samples subjected to shorter fixation periods. Moreover, the detection of labile epitopes (such as Nestin) in the human hippocampus required the use of mild detergents. The application of this strictly controlled methodology allowed reconstruction of the entire AHN process, thus revealing the presence of neural stem cells, proliferative progenitors, neuroblasts, and immature neurons at distinct stages of differentiation in the human DG. The data reviewed here demonstrate that methodology is of utmost importance when studying AHN by means of distinct techniques across the phylogenetic scale. In this regard, we summarize the major findings made by our group that emphasize that overlooking fundamental technical principles might have consequences for any given research fieldAssociation for Frontotemporal Degeneration; Banco de Santander; Center for Networked Biomedical Research on Neurodegenerative Diseases; Consejo Nacional de Ciencia y Tecnología (CONACYT), Grant/Award Number: 385084; European Research Council, Grant/Award Number: ERC-CoG2020-101001916; Fundacion Ram on Areces; Secretaria de Educacion, Ciencia Tecnología e Innovacion (SECTEI) of the Regional Government of Ciudad de México (CDMX), Grant/Award Number: SECTEI/159/2021; Spanish Ministry of Economy and Competitiveness, Grant/Award Numbers: PID2020-113007RB-I00, RYC-2015-171899, SAF-2017-82185-R; The Alzheimer's Association, Grant/Award Numbers: 2015-NIRG-340709, AARG-17-528125, AARG-17-528125-RAPI

Activity-Dependent Reconnection of Adult-Born Dentate Granule Cells in a Mouse Model of Frontotemporal Dementia

Frontotemporal dementia (FTD) is characterized by neuronal loss in the frontal and temporal lobes of the brain. Here, we provide the first evidence of striking morphological alterations in dentate granule cells (DGCs) of FTD patients and in a mouse model of the disease, Tau VLW mice. Taking advantage of the fact that the hippocampal dentate gyrus (DG) gives rise to newborn DGCs throughout the lifetime in rodents, we used RGB retroviruses to study the temporary course of these alterations in newborn DGCs of female Tau VLW mice. In addition, retroviruses that encode either PSD95:GFP or Syn:GFP revealed striking alterations in the afferent and efferent connectivity of newborn Tau VLW DGCs, and monosynaptic retrograde rabies virus tracing showed that these cells are disconnected from distal brain regions and local sources of excitatory innervation. However, the same cells exhibited a predominance of local inhibitory innervation. Accordingly, the expression of presynaptic and postsynaptic markers of inhibitory synapses was markedly increased in the DG of Tau VLW mice and FTD patients. Moreover, an increased number of neuropeptide Y-positive interneurons in the DG correlated with a reduced number of activated egr-1 + DGCs in Tau VLW mice. Finally, we tested the therapeutic potential of environmental enrichment and chemoactivation to reverse these alterations in mice. Both strategies reversed the morphological alterations of newborn DGCs and partially restored their connectivity in a mouse model of the disease. Moreover, our data point to remarkable morphological similarities between the DGCs of Tau VLW mice and FTD patients.Fil: Terreros Roncal, Julia. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Flor García, Miguel. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Moreno Jiménez, Elena P.. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Pallas Bazarra, Noemí. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Rábano, Alberto. No especifíca;Fil: Sah, Nirnath. National Institutes of Health; Estados UnidosFil: Van Praag, Henriette. National Institutes of Health; Estados UnidosFil: Giacomini, Damiana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Schinder, Alejandro Fabián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Ávila, Jesús. Universidad Autónoma de Madrid. Facultad de Ciencias; EspañaFil: Llorens Martín, Maria. Universidad Autónoma de Madrid. Facultad de Ciencias; Españ