69 research outputs found
Diseño de un plan de mercadeo para la comercialización y el posicionamiento del filtro purificador y ahorrador de agua para llave de cocina “Purify” en la ciudad de Pereira
La formulación de este proyecto de investigación se enfoca en diseño de un plan de mercadeo para la comercialización y el posicionamiento del filtro purificador y ahorrador de agua para llave de cocina “Purify” en la ciudad de Pereira. Este planteamiento nace a partir de que actualmente ha crecido la tendencia de bienestar en el hogar; sin embargo, muy pocas personas conocen los filtros purificadores de agua Purify y sus beneficios. Se crea la necesidad de indagar y atender los comentarios de los clientes con el fin de ofrecer el producto en almacenes de cadena, grandes superficies y tener un punto de venta directo en la ciudad. Por esta razón se procedió a encuestar, analizar y observar una muestra de la población total de Pereira, en la que se tiene una alta expectativa de generar nuevos prospectos de negocios y tener nuevos clientes a través de un punto de venta directo en almacenes de cadena y grandes superficies, para que la empresa pueda extenderse geográficamente en el municipio de Pereira, y así los clientes puedan visitar los mostradores de venta y obtengan asesoramiento, capacitación y muestra de los filtros purificadores de agua Purify. Finalmente, para este trabajo, se diseñó un plan de mercado, con el objetivo de abrir nuevos mercados potenciales, desarrollando estrategias, tácticas y herramientas para su implementación
Aula virtual para las ciencias sociales
La implementación de algunas herramientas de la web 2.0 en el proceso de enseñanza y aprendizaje en el área de las ciencias sociales específicamente y haciendo uso del estándar (Utilizo coordenadas, escalas y convenciones para ubicar los fenómenos históricos y culturales en mapas y planos de representación) surge como propuesta pedagógica mediatizada, cuyo objetivo es analizar qué impacto generan las TIC dentro de los procesos escolares de la institución Educativa Centenario específicamente en el grado 5to para la elaboración de una herramienta pedagógica que facilite a los estudiantes la aprehensión de los contenidos académicos.
Esta herramienta busca evidenciar que impacto genera el entorno virtual “Aula Virtual para las ciencias sociales” apoyados en algunas herramientas de la Web 2.0 (plataforma google, Wix, Educaplay, youtube, blog, street view, Facebook) que posibilitan la construcción del conocimiento de manera eficaz en el desarrollo de la temática a trabajar
Mast Cell and Astrocyte Hemichannels and Their Role in Alzheimer\u27s Disease, ALS, and Harmful Stress Conditions
Considered relevant during allergy responses, numerous observations have also identified mast cells (MCs) as critical effectors during the progression and modulation of several neuroinflammatory conditions, including Alzheimer\u27s disease (AD) and amyotrophic lateral sclerosis (ALS). MC granules contain a plethora of constituents, including growth factors, cytokines, chemokines, and mitogen factors. The release of these bioactive substances from MCs occurs through distinct pathways that are initiated by the activation of specific plasma membrane receptors/channels. Here, we focus on hemichannels (HCs) formed by connexins (Cxs) and pannexins (Panxs) proteins, and we described their contribution to MC degranulation in AD, ALS, and harmful stress conditions. Cx/Panx HCs are also expressed by astrocytes and are likely involved in the release of critical toxic amounts of soluble factors-such as glutamate, adenosine triphosphate (ATP), complement component 3 derivate C3a, tumor necrosis factor (TNFalpha), apoliprotein E (ApoE), and certain miRNAs-known to play a role in the pathogenesis of AD, ALS, and other neurodegenerative disorders. We propose that blocking HCs on MCs and glial cells offers a promising novel strategy for ameliorating the progression of neurodegenerative diseases by reducing the release of cytokines and other pro-inflammatory compounds
Huella de carbono: implementación de estrategias en el Índice Sustentable en México
Objetivo: esta investigación tiene como propósito fundamental presentar un estudio sobre la integración de estrategias relacionadas con la huella de carbono en las empresas que cotizan en la Bolsa Mexicana de Valores y aparecen en el índice sustentable. Método: para el desarrollo de la misma, se empleó un estudio de carácter descriptivo con un diseño no experimental en la cual se analizó la implementación de estrategias relacionadas con los inventarios de carbono de treinta (30) empresas listadas en el Índice de Precios y Cotizaciones Sustentable de la Bolsa Mexicana de Valores. Resultados y Discusiones: se encontró que la implementación de dichas estrategias varía según la empresa; sin embargo, existen diversos puntos en las que la mayoría coinciden. El principal hallazgo es que la mayor parte de las empresas del índice participan en proyectos internacionales de reportes de sustentabilidad y de disposición abierta de información relacionada con su huella de carbono e impacto en el cambio climático. Conclusiones: no obstante, lograr las metas establecidas de reducción de emisiones de gases de efecto invernadero con relación a los acuerdos internacionales requiere de grandes esfuerzos, formalización de políticas y voluntad de parte de las empresas, los consumidores y las instituciones gubernamentales
Análisis in vivo de la vasculopatía arterial pulmonar mediante ultrasonido intravascular (IVUS) en pacientes con insuficiencia respiratoria crónica evaluados para trasplante pulmonar
El objetivo del estudio es evaluar el remodelado estructural y funcional de las arterias pulmonares asociado a insuficiencia respiratoria crónica severa, mediante ecografía intravascular (IVUS). Se incluyeron 80 pacientes en estudio pretrasplante pulmonar a los que se les realizó cateterismo cardiaco derecho e IVUS de una arteria pulmonar de mediano calibre. A través del IVUS se determinó el módulo elástico, pulsatilidad y porcentaje de fibrosis arterial. La insuficiencia respiratoria crónica se asoció a una vasculopatía arterial pulmonar severa, independientemente de la presencia de hipertensión pulmonar. Los pacientes con EPOC (enfermedad pulmonar obstructiva crónica) presentaban un mayor grado de fibrosis arterial, mientras que los pacientes con EPID (enfermedad pulmonar intersticial difusa) presentaban mayor rigidez arterial.L'objectiu de l'estudi és avaluar el remodelat estructural i funcional de les artèries pulmonars associat a insuficiència respiratòria crònica severa, mitjançant ecografia intravascular (IVUS). Es van incloure 80 malalts en estudi pretrasplant pulmonar als quals se'ls va realitzar cateterisme cardiac dret i IVUS d'una artèria pulmonar de mig calibre. A través del IVUS es va determinar el mòdul elàstic, pulsatilitat i percentatge de fibrosi arterial. La insuficiència respiratòria crònica es va associar a una vasculopatia arterial pulmonar severa, independentment de la presència d'hipertensió pulmonar. Els malalts amb MPOC (malatia pulmonar obstructiva crònica) presentaven un major grau de fibrosi arterial, mentre que els malalts amb MPID (malaltia pulmonar intersticial difusa) presentaven major rigidesa arterial
Widespread loss of the silencing epigenetic mark H3K9me3 in astrocytes and neurons along with hippocampal-dependent cognitive impairment in C9orf72 BAC transgenic mice
Background: Hexanucleotide repeat expansions of the G4C2 motif in a non-coding region of the C9ORF72 gene are the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Tissues from C9ALS/FTD patients and from mouse models of ALS show RNA foci, dipeptide-repeat proteins, and notably, widespread alterations in the transcriptome. Epigenetic processes regulate gene expression without changing DNA sequences and therefore could account for the altered transcriptome profiles in C9ALS/FTD; here, we explore whether the critical repressive marks H3K9me2 and H3K9me3 are altered in a recently developed C9ALS/FTD BAC mouse model (C9BAC). Results: Chromocenters that constitute pericentric constitutive heterochromatin were visualized as DAPI- or Nucblue-dense foci in nuclei. Cultured C9BAC astrocytes exhibited a reduced staining signal for H3K9me3 (but not for H3K9me2) at chromocenters that was accompanied by a marked decline in the global nuclear level of this mark. Similar depletion of H3K9me3 at chromocenters was detected in astrocytes and neurons of the spinal cord, motor cortex, and hippocampus of C9BAC mice. The alterations of H3K9me3 in the hippocampus of C9BAC mice led us to identify previously undetected neuronal loss in CA1, CA3, and dentate gyrus, as well as hippocampal-dependent cognitive deficits. Conclusions: Our data indicate that a loss of the repressive mark H3K9me3 in astrocytes and neurons in the central nervous system of C9BAC mice represents a signature during neurodegeneration and memory deficit of C9ALS/FTD. © 2020 The Author(s).Indexación: Scopu
Mature iPSC-derived astrocytes of an ALS/FTD patient carrying the TDP43A90V mutation display a mild reactive state and release polyP toxic to motoneurons
Astrocytes play a critical role in the maintenance of a healthy central nervous system and astrocyte dysfunction has been implicated in various neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). There is compelling evidence that mouse and human ALS and ALS/FTD astrocytes can reduce the number of healthy wild-type motoneurons (MNs) in co-cultures or after treatment with astrocyte conditioned media (ACM), independently of their genotype. A growing number of studies have shown that soluble toxic factor(s) in the ACM cause non-cell autonomous MN death, including our recent identification of inorganic polyphosphate (polyP) that is excessively released from mouse primary astrocytes (SOD1, TARDBP, and C9ORF72) and human induced pluripotent stem cells (iPSC)-derived astrocytes (TARDBP) to kill MNs. However, others have reported that astrocytes carrying mutant TDP43 do not produce detectable MN toxicity. This controversy is likely to arise from the findings that human iPSC-derived astrocytes exhibit a rather immature and/or reactive phenotype in a number of studies. Here, we have succeeded in generating a highly homogenous population of functional quiescent mature astrocytes from control subject iPSCs. Using identical conditions, we also generated mature astrocytes from an ALS/FTD patient carrying the TDP43A90V mutation. These mutant TDP43 patient-derived astrocytes exhibit key pathological hallmarks, including enhanced cytoplasmic TDP-43 and polyP levels. Additionally, mutant TDP43 astrocytes displayed a mild reactive signature and an aberrant function as they were unable to promote synaptogenesis of hippocampal neurons. The polyP-dependent neurotoxic nature of the TDP43A90V mutation was further confirmed as neutralization of polyP in ACM derived from mutant TDP43 astrocytes prevented MN death. Our results establish that human astrocytes carrying the TDP43A90V mutation exhibit a cell-autonomous pathological signature, hence providing an experimental model to decipher the molecular mechanisms underlying the generation of the neurotoxic phenotype
Mathematical modeling of the dynamic storage of iron in ferritin
<p>Abstract</p> <p>Background</p> <p>Iron is essential for the maintenance of basic cellular processes. In the regulation of its cellular levels, ferritin acts as the main intracellular iron storage protein. In this work we present a mathematical model for the dynamics of iron storage in ferritin during the process of intestinal iron absorption. A set of differential equations were established considering kinetic expressions for the main reactions and mass balances for ferritin, iron and a discrete population of ferritin species defined by their respective iron content.</p> <p>Results</p> <p>Simulation results showing the evolution of ferritin iron content following a pulse of iron were compared with experimental data for ferritin iron distribution obtained with purified ferritin incubated <it>in vitro </it>with different iron levels. Distinctive features observed experimentally were successfully captured by the model, namely the distribution pattern of iron into ferritin protein nanocages with different iron content and the role of ferritin as a controller of the cytosolic labile iron pool (cLIP). Ferritin stabilizes the cLIP for a wide range of total intracellular iron concentrations, but the model predicts an exponential increment of the cLIP at an iron content > 2,500 Fe/ferritin protein cage, when the storage capacity of ferritin is exceeded.</p> <p>Conclusions</p> <p>The results presented support the role of ferritin as an iron buffer in a cellular system. Moreover, the model predicts desirable characteristics for a buffer protein such as effective removal of excess iron, which keeps intracellular cLIP levels approximately constant even when large perturbations are introduced, and a freely available source of iron under iron starvation. In addition, the simulated dynamics of the iron removal process are extremely fast, with ferritin acting as a first defense against dangerous iron fluctuations and providing the time required by the cell to activate slower transcriptional regulation mechanisms and adapt to iron stress conditions. In summary, the model captures the complexity of the iron-ferritin equilibrium, and can be used for further theoretical exploration of the role of ferritin in the regulation of intracellular labile iron levels and, in particular, as a relevant regulator of transepithelial iron transport during the process of intestinal iron absorption.</p
Decoupling of soil nutrient cycles as a function of aridity in global drylands
18 páginas.- 10 figuras.- 72 referencias.- Online Content Any additional Methods, Extended Data display items and Source Data are available in the online version of the paper; references unique to these
sections appear only in the online paper..- Puede conseguir el texto completo en el Portal de la producción científica de la Universidad Complutense de Madrid https://produccioncientifica.ucm.es/documentos/5ec78dc52999520a1d557660 .- o en lel respositorio institucional CONICET digital https://ri.conicet.gov.ar/bitstream/handle/11336/29204/CONICET_Digital_Nro.ead4e2ed-0da6-4041-814b-259e8f27bbf6_D.pdf?sequence=5&isAllowed=yThe biogeochemical cycles of carbon (C), nitrogen (N) and phosphorus (P) are interlinked by primary production, respiration and decomposition in terrestrial ecosystems1. It has been suggested that the C, N and P cycles could become uncoupled under rapid climate change because of the different degrees of control exerted on the supply of these elements by biological and geochemical processes1,2,3,4,5. Climatic controls on biogeochemical cycles are particularly relevant in arid, semi-arid and dry sub-humid ecosystems (drylands) because their biological activity is mainly driven by water availability6,7,8. The increase in aridity predicted for the twenty-first century in many drylands worldwide9,10,11 may therefore threaten the balance between these cycles, differentially affecting the availability of essential nutrients12,13,14. Here we evaluate how aridity affects the balance between C, N and P in soils collected from 224 dryland sites from all continents except Antarctica. We find a negative effect of aridity on the concentration of soil organic C and total N, but a positive effect on the concentration of inorganic P. Aridity is negatively related to plant cover, which may favour the dominance of physical processes such as rock weathering, a major source of P to ecosystems, over biological processes that provide more C and N, such as litter decomposition12,13,14. Our findings suggest that any predicted increase in aridity with climate change will probably reduce the concentrations of N and C in global drylands, but increase that of P. These changes would uncouple the C, N and P cycles in drylands and could negatively affect the provision of key services provided by these ecosystems.This research is supported by the European Research Council (ERC) under the European Community's Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement no. 242658 (BIOCOM), and by the Ministry of Science and Innovation of the Spanish Government, grant no. CGL2010-21381. CYTED funded networking activities (EPES, Acción 407AC0323). M.D.-B. was supported by a PhD fellowship from the Pablo de Olavide University.Peer reviewe
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