276 research outputs found
High-order Calderon multiplicative preconditioner for time domain electric field integral equations
Coxiella burnetii and Leishmania Mexicana Residing Within Similar Parasitophorous Vacuoles Elicit Disparate Host Responses
Coxiella burnetii is a bacterium that thrives in an acidic parasitophorous vacuole (PV) derived from lysosomes. Leishmania mexicana, a eukaryote, has also independently evolved to live in a morphologically similar PV. As Coxiella and Leishmania are highly divergent organisms that cause different diseases, we reasoned that their respective infections would likely elicit distinct host responses despite producing phenotypically similar parasite-containing vacuoles. The objective of this study was to investigate, at the molecular level, the macrophage response to each pathogen. Infection of THP-1 (human monocyte/macrophage) cells with Coxiella and Leishmania elicited disparate host responses. At 5 days post-infection, when compared to uninfected cells, 1057 genes were differentially expressed (746 genes up-regulated and 311 genes downregulated) in C. burnetii infected cells, whereas 698 genes (534 genes up-regulated and 164 genes down-regulated) were differentially expressed in L. mexicana infected cells. Interestingly, of the 1755 differentially expressed genes identified in this study, only 126 genes (∼7%) are common to both infections. We also discovered that 1090 genes produced mRNA isoforms at significantly different levels under the two infection conditions, suggesting that alternate proteins encoded by the same gene might have important roles in host response to each infection. Additionally, we detected 257 micro RNAs (miRNAs) that were expressed in THP-1 cells, and identified miRNAs that were specifically expressed during Coxiella or Leishmania infections. Collectively, this study identified host mRNAs and miRNAs that were influenced by Coxiella and/or Leishmania infections, and our data indicate that although their PVs are morphologically similar, Coxiella and Leishmania have evolved different strategies that perturb distinct host processes to create and thrive within their respective intracellular niches
“CUATRO ESQUINAS”: el juego tradicional cubano
The Cuban population, based on our popular councils, demands the recognition of the modality of the Four Corner (Ball at Hand), as Intangible Cultural Heritage of our country; given by its roots and massive practice in children, school, youth and social ages in neighborhoods and communities throughout the national territory, considered as a traditional Cuban game, a genuine expression of a pre-sports game inspired by baseball recognized as our National sport. On the other hand, we identify the need to systematize the theoretical and methodological underpinnings of this modality, its emergence and evolutionary development; in this sense there is no bibliography, which reflects the origins, antecedents or precedents in the practice of the ball at hand in our country; in consultation with several baseball specialists and the development of traditional Cuban games, all express their ignorance about the emergence of this modality; as well as intellectuals and personalities with knowledge and experience in Cuban traditions; however, the different ways of practicing in each locality are evident in our neighborhoods and communities; as a healthy recreational option that manifests spontaneously, promoting the development of physical abilities, technical-tactical skills and the formation of values; At the same time, it is necessary to identify the requirements in the technical and methodological order, its regulation and management strategy in the communities in the short, medium and long term; that condition the essence of traditional autochthonous game, as an expression of the intangible Cuban cultural heritage.La población cubana a partir de nuestros consejos populares, demanda el reconocimiento de la modalidad del Cuatro Esquina (Pelota a la Mano), como Patrimonio Cultural Inmaterial de nuestro país; dado por su arraigo y práctica masiva en las edades infantiles, escolares, juveniles y sociales en los barrios y las comunidades de todo el territorio nacional, considerado como juego tradicional cubano, expresión genuina de un juego pre-deportivo inspirado en el Béisbol reconocido como nuestro deporte nacional. Por otra parte se identifica la necesidad de sistematizar los sustentos teóricos y metodológicos de esta modalidad, su surgimiento y desarrollo evolutivo; en tal sentido no se cuenta con una bibliografía, que refleje los orígenes, antecedentes o precedentes en la práctica de la pelota a la mano en nuestro país; en consulta con varios especialistas del béisbol y el desarrollo de los juegos tradicionales cubanos, todos expresan su desconocimiento acerca del surgimiento de esta modalidad; así como también los intelectuales y personalidades con conocimientos y experiencias en las tradiciones cubanas; sin embargo, se evidencian en nuestros barrios y comunidades las diferentes formas de practicarse en cada localidad; como una sana opción recreativa que se manifiesta de manera espontánea, potenciando el desarrollo de capacidades físicas, habilidades técnico-tácticas y la formación de valores; a su vez es preciso identificar los requerimientos en el orden técnico y metodológico, su reglamentación y estrategia de gestión en las comunidades a corto, mediano y largo plazo; que condicionen la esencia de juego tradicional autóctono, como expresión del patrimonio cultural inmaterial cubano. 
A Read/Write Mechanism Connects p300 Bromodomain Function to H2A.Z Acetylation
Acetylation of the histone variant H2A.Z (H2A.Zac) occurs at active regulatory regions associated with gene expression. Although the Tip60 complex is proposed to acetylate H2A.Z, functional studies suggest additional enzymes are involved. Here, we show that p300 acetylates H2A.Z at multiple lysines. In contrast, we found that although Tip60 does not efficiently acetylate H2A.Z in vitro, genetic inhibition of Tip60 reduces H2A.Zac in cells. Importantly, we found that interaction between the p300-bromodomain and H4 acetylation (H4ac) enhances p300-driven H2A.Zac. Indeed, H2A.Zac and H4ac show high genomic overlap, especially at active promoters. We also reveal unique chromatin features and transcriptional states at enhancers correlating with co-occurrence or exclusivity of H4ac and H2A.Zac. We propose that differential H4 and H2A.Z acetylation signatures can also define the enhancer state. In conclusion, we show both Tip60 and p300 contribute to H2A.Zac and reveal molecular mechanisms of writer/reader crosstalk between H2A.Z and H4 acetylation through p300
Las alternativas ciudadanas para otros mundos posibles: pensamiento y experiencias
El documento está conformado por tres partes: la primera define algunos conceptos y expone ciertas teorías sobre el desarrollo y las alternativas (los artículos que componen este apartado son: "Diversidad y dinamismo de las alternativas ciudadanas", "¿Desarrollo alternativo o alternativas al desarrollo? repensando el concepto desde el territorio y el sur global"); la segunda, hace referencia a la construcción de algunas experiencias concretas relacionadas con las alternativas ciudadanas ("La gestión compleja del agua", "La alternativa educativa intercultural wixárika"; "Los procesos sociales en la construcción de alternativas a conflictos ambientales en la cuenca alta del río Santiago"). La tercera parte consiste en una propuesta de investigación sobre las alternativas ciudadanas ("Las alternativas ciudadanas: una propuesta de análisis").ITESO, A.C
Modelo para la optimización del costo de operación de un campo de pozos en acuíferos
Ramos-Arzola, L. C., Cabrera-Estupiñán, E., Molina-Pérez, D., Hernández-Valdés, A. O., & Marón-Domínguez, D. E. (mayo-junio, 2017). Modelo para la optimización del costo de operación de un campo de pozos en acuíferos. Tecnología y Ciencias del Agua, 8(3), 39-53.
El componente de mayor costo en la producción de agua subterránea en un sistema de suministro (una vez que los pozos están construidos) es el bombeo de agua desde los pozos. En la presente contribución se propone un nuevo módulo en MADA (modelo de administración de acuíferos), que se basa en la inclusión de un modelo de simulaciónoptimización para la minimización del costo de operación en acuíferos. La propuesta utiliza un modelo de simulación bidimensional del flujo del agua subterránea (AQÜIMPE) basado en el método de los elementos finitos. Se emplea el enfoque matriz respuesta para vincular AQÜIMPE con un problema de programación cuadrática, que se resuelve empleando la función quadprog del asistente matemático MATLAB. Se aplica el modelo en la administración de la explotación del acuífero Cuenca Sur y se obtiene una política de explotación que permite un 15% de ahorro del costo de bombeo en relación con el costo de la explotación real del año 2007. Además, el patrón de explotación obtenido satisface un conjunto de restricciones de demanda, de niveles en el acuífero y de capacidad instalada en cada pozo de explotación
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
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