1,076 research outputs found
The importance of detailed epigenomic profiling of different cell types within organs.
The human body consists of hundreds of kinds of cells specified from a single genome overlaid with cell type-specific epigenetic information. Comprehensively profiling the body's distinct epigenetic landscapes will allow researchers to verify cell types used in regenerative medicine and to determine the epigenetic effects of disease, environmental exposures and genetic variation. Key marks/factors that should be investigated include regions of nucleosome-free DNA accessible to regulatory factors, histone marks defining active enhancers and promoters, DNA methylation levels, regulatory RNAs, and factors controlling the three-dimensional conformation of the genome. Here we use the lung to illustrate the importance of investigating an organ's purified cell epigenomes, and outline the challenges and promise of realizing a comprehensive catalog of primary cell epigenomes
A comparative study of experimental configurations in synchrotron pair distribution function
The identification and quantification of amorphous components and nanocrystalline phases
with very small crystal sizes, smaller than ~3 nm, within samples containing crystalline phases is
very challenging. However, this is important as there are several types of systems that contain these
matrices: building materials, glass-ceramics, some alloys, etc. The total scattering synchrotron pair
distribution function (PDF) can be used to characterize the local atomic order of the nanocrystalline
components and to carry out quantitative analyses in complex mixtures. Although the resolution in
momentum transfer space has been widely discussed, the resolution in the interatomic distance space
has not been discussed to the best of our knowledge. Here, we report synchrotron PDF data collected at
three beamlines in different experimental configurations and X-ray detectors. We not only discuss the
effect of the resolution in Q-space, Qmax ins of the recorded data and Qmax of the processed data, but we
also discuss the resolution in the interatomic distance (real) space. A thorough study of single-phase
crystalline nickel used as standard was carried out. Then, selected cement-related samples including
anhydrous tricalcium and dicalcium silicates, and pastes derived from the hydration of tricalcium
silicate and ye’elimite with bassanite were analyzed.This work is part of the PhD of Mr. Jesus D. Zea-Garcia. This work was supported by Spanish MINECO and FEDER [BIA2017-82391-R research project and I3 [IEDI-2016-0079] program]
Effect of ultrasound intensification on the supercritical fluid extraction of phytochemicals from Agave salmiana bagasse
[EN] The aim of this work was to evaluate the effect of ultrasound on supercritical fluid extraction for the recovery of antioxidants and saponins from agave bagasse as a green extraction technique. When a mass load of 0.086 g/cm(3) was used, ultrasound effect was not observed, due to sample swelling and compaction within the cell. For 0.043 g/cm(3), the intensification effect of ultrasound was significant (p < 0.05) and its magnitude depended on the transducer geometry. For a multiplate transducer geometry, antioxidant capacity increased from 12.18 +/- 1.01 to 20.91 +/- 1.66 mu mol TE/g; and saponins from 19.05 +/- 1.67 to 61.59 +/- 1.99 mu g/g, when ultrasound was applied. Although the amount of bioactives extracted is low, the use of a multiplate transducer design was able to intensify the supercritical fluid extraction of phytochemicals from agave bagasse. Consequently, this type of transducer can become an alternative for the application of ultrasound on the supercritical fluid extraction of other suitable agro-industrial by-productsThe authors are grateful for the financial support from CONACYT CVU 270166, Mexico; NutriOmics Chair from Tecnologico de Monterrey, Mexico; and Nutrigenomics Research Chair from Fundacion FEMSA, Mexico. We thank the technical support from the ASPA group technicians and Albino Vargas from AGMEL S.A de C.V for donating agave bagasse for this projectSantos-Zea, L.; Gutierrez-Uribe, JA.; Benedito Fort, JJ. (2019). Effect of ultrasound intensification on the supercritical fluid extraction of phytochemicals from Agave salmiana bagasse. The Journal of Supercritical Fluids. 144:98-107. https://doi.org/10.1016/j.supflu.2018.10.013S98107144Pereira, C. G., & Meireles, M. A. A. (2009). Supercritical Fluid Extraction of Bioactive Compounds: Fundamentals, Applications and Economic Perspectives. Food and Bioprocess Technology, 3(3), 340-372. doi:10.1007/s11947-009-0263-2HERRERO, M., CIFUENTES, A., & IBANEZ, E. (2006). Sub- and supercritical fluid extraction of functional ingredients from different natural sources: Plants, food-by-products, algae and microalgaeA review. Food Chemistry, 98(1), 136-148. doi:10.1016/j.foodchem.2005.05.058Farías-Campomanes, A. M., Rostagno, M. A., & Meireles, M. A. A. (2013). Production of polyphenol extracts from grape bagasse using supercritical fluids: Yield, extract composition and economic evaluation. The Journal of Supercritical Fluids, 77, 70-78. doi:10.1016/j.supflu.2013.02.006Cruz, M. V., Paiva, A., Lisboa, P., Freitas, F., Alves, V. D., Simões, P., … Reis, M. A. M. (2014). Production of polyhydroxyalkanoates from spent coffee grounds oil obtained by supercritical fluid extraction technology. Bioresource Technology, 157, 360-363. doi:10.1016/j.biortech.2014.02.013Riera, E., Blanco, A., García, J., Benedito, J., Mulet, A., Gallego-Juárez, J. A., & Blasco, M. (2010). High-power ultrasonic system for the enhancement of mass transfer in supercritical CO2 extraction processes. Physics Procedia, 3(1), 141-146. doi:10.1016/j.phpro.2010.01.020Rodríguez, Ó., Ortuño, C., Simal, S., Benedito, J., Femenia, A., & Rosselló, C. (2014). Acoustically assisted supercritical CO2 extraction of cocoa butter: Effects on kinetics and quality. The Journal of Supercritical Fluids, 94, 30-37. doi:10.1016/j.supflu.2014.06.017Santos-Zea, L., Antunes-Ricardo, M., Gutierrez-Uribe, J. A., García-Pérez, J. V., & Benedito, J. (2018). Effect of ultrasound transducer design on the acoustically-assisted supercritical fluid extraction of antioxidants from oregano. Ultrasonics Sonochemistry, 47, 47-56. doi:10.1016/j.ultsonch.2018.04.019Pasquel Reátegui, J. L., Machado, A. P. da F., Barbero, G. F., Rezende, C. A., & Martínez, J. (2014). Extraction of antioxidant compounds from blackberry (Rubus sp.) bagasse using supercritical CO2 assisted by ultrasound. The Journal of Supercritical Fluids, 94, 223-233. doi:10.1016/j.supflu.2014.07.019Santos, P., Aguiar, A. C., Barbero, G. F., Rezende, C. A., & Martínez, J. (2015). Supercritical carbon dioxide extraction of capsaicinoids from malagueta pepper (Capsicum frutescens L.) assisted by ultrasound. Ultrasonics Sonochemistry, 22, 78-88. doi:10.1016/j.ultsonch.2014.05.001Dias, A. L. B., Arroio Sergio, C. S., Santos, P., Barbero, G. F., Rezende, C. A., & Martínez, J. (2016). Effect of ultrasound on the supercritical CO2 extraction of bioactive compounds from dedo de moça pepper (Capsicum baccatum L. var. pendulum). Ultrasonics Sonochemistry, 31, 284-294. doi:10.1016/j.ultsonch.2016.01.013Balachandran, S., Kentish, S. E., Mawson, R., & Ashokkumar, M. (2006). Ultrasonic enhancement of the supercritical extraction from ginger. Ultrasonics Sonochemistry, 13(6), 471-479. doi:10.1016/j.ultsonch.2005.11.006Riera, E., Golás, Y., Blanco, A., Gallego, J. A., Blasco, M., & Mulet, A. (2004). Mass transfer enhancement in supercritical fluids extraction by means of power ultrasound. Ultrasonics Sonochemistry, 11(3-4), 241-244. doi:10.1016/j.ultsonch.2004.01.019Bitencourt, R. G., Queiroga, C. L., Montanari Junior, Í., & Cabral, F. A. (2014). Fractionated extraction of saponins from Brazilian ginseng by sequential process using supercritical CO2, ethanol and water. The Journal of Supercritical Fluids, 92, 272-281. doi:10.1016/j.supflu.2014.06.009Luo, D., Qiu, T., & Lu, Q. (2007). Ultrasound-assisted extraction of ginsenosides in supercritical CO2 reverse microemulsions. Journal of the Science of Food and Agriculture, 87(3), 431-436. doi:10.1002/jsfa.2716Hurtado-Benavides, A., Dorado A., D., & Sánchez-Camargo, A. del P. (2016). Study of the fatty acid profile and the aroma composition of oil obtained from roasted Colombian coffee beans by supercritical fluid extraction. The Journal of Supercritical Fluids, 113, 44-52. doi:10.1016/j.supflu.2016.03.008Hu, A., Zhao, S., Liang, H., Qiu, T., & Chen, G. (2007). Ultrasound assisted supercritical fluid extraction of oil and coixenolide from adlay seed. Ultrasonics Sonochemistry, 14(2), 219-224. doi:10.1016/j.ultsonch.2006.03.005Fornari, T., Vicente, G., Vázquez, E., García-Risco, M. R., & Reglero, G. (2012). Isolation of essential oil from different plants and herbs by supercritical fluid extraction. Journal of Chromatography A, 1250, 34-48. doi:10.1016/j.chroma.2012.04.051Antunes-Ricardo, M., Gutiérrez-Uribe, J. A., & Guajardo-Flores, D. (2017). Extraction of isorhamnetin conjugates from Opuntia ficus-indica (L.) Mill using supercritical fluids. The Journal of Supercritical Fluids, 119, 58-63. doi:10.1016/j.supflu.2016.09.003A., N.-Z., & F., S.-T. (2009). Agaves as a Raw Material: Recent Technologies and Applications. Recent Patents on Biotechnology, 3(3), 185-191. doi:10.2174/187220809789389144Escalante, A., López Soto, D. R., Velázquez Gutiérrez, J. E., Giles-Gómez, M., Bolívar, F., & López-Munguía, A. (2016). Pulque, a Traditional Mexican Alcoholic Fermented Beverage: Historical, Microbiological, and Technical Aspects. Frontiers in Microbiology, 7. doi:10.3389/fmicb.2016.01026Caspeta, L., Caro-Bermúdez, M. A., Ponce-Noyola, T., & Martinez, A. (2014). Enzymatic hydrolysis at high-solids loadings for the conversion of agave bagasse to fuel ethanol. Applied Energy, 113, 277-286. doi:10.1016/j.apenergy.2013.07.036Pinos-Rodríguez, J. M., Aguirre-Rivera, J. R., García-López, J. C., Rivera-Miranda, M. T., González-Muñoz, S., López-Aguirre, S., & Chávez-Villalobos, D. (2006). Use of «Maguey» (Agave salmianaOtto ex. Salm-Dick) as Forage for Ewes. Journal of Applied Animal Research, 30(2), 101-107. doi:10.1080/09712119.2006.9706596Figueroa, L., Santos-Zea, L., Escalante, A., & Gutiérrez-Uribe, J. (2017). Mass Spectrometry-Based Metabolomics of Agave Sap (Agave salmiana) after Its Inoculation with Microorganisms Isolated from Agave Sap Concentrate Selected to Enhance Anticancer Activity. Sustainability, 9(11), 2095. doi:10.3390/su9112095Puente-Garza, C. A., Espinosa-Leal, C. A., & García-Lara, S. (2018). Steroidal Saponin and Flavonol Content and Antioxidant Activity during Sporophyte Development of Maguey (Agave salmiana). Plant Foods for Human Nutrition, 73(4), 287-294. doi:10.1007/s11130-018-0684-zPulido, R., Bravo, L., & Saura-Calixto, F. (2000). Antioxidant Activity of Dietary Polyphenols As Determined by a Modified Ferric Reducing/Antioxidant Power Assay. Journal of Agricultural and Food Chemistry, 48(8), 3396-3402. doi:10.1021/jf9913458Santos-Zea, L., Leal-Díaz, A. M., Jacobo-Velázquez, D. A., Rodríguez-Rodríguez, J., García-Lara, S., & Gutiérrez-Uribe, J. A. (2016). Characterization of concentrated agave saps and storage effects on browning, antioxidant capacity and amino acid content. Journal of Food Composition and Analysis, 45, 113-120. doi:10.1016/j.jfca.2015.10.005Santos-Zea, L., Rosas-Pérez, A. M., Leal-Díaz, A. M., & Gutiérrez-Uribe, J. A. (2016). Variability in Saponin Content, Cancer Antiproliferative Activity and Physicochemical Properties of Concentrated Agave Sap. Journal of Food Science, 81(8), H2069-H2075. doi:10.1111/1750-3841.13376Mancilla-Margalli, N. A., & López, M. G. (2002). Generation of Maillard Compounds from Inulin during the Thermal Processing of Agave tequilana Weber Var. azul. Journal of Agricultural and Food Chemistry, 50(4), 806-812. doi:10.1021/jf0110295Monroy, Y. M., Rodrigues, R. A. F., Sartoratto, A., & Cabral, F. A. (2016). Influence of ethanol, water, and their mixtures as co-solvents of the supercritical carbon dioxide in the extraction of phenolics from purple corn cob ( Zea mays L.). The Journal of Supercritical Fluids, 118, 11-18. doi:10.1016/j.supflu.2016.07.019Li, B., Xu, Y., Jin, Y.-X., Wu, Y.-Y., & Tu, Y.-Y. (2010). Response surface optimization of supercritical fluid extraction of kaempferol glycosides from tea seed cake. Industrial Crops and Products, 32(2), 123-128. doi:10.1016/j.indcrop.2010.04.002Liu, S., Yang, F., Zhang, C., Ji, H., Hong, P., & Deng, C. (2009). Optimization of process parameters for supercritical carbon dioxide extraction of Passiflora seed oil by response surface methodology. The Journal of Supercritical Fluids, 48(1), 9-14. doi:10.1016/j.supflu.2008.09.013Barrales, F. M., Rezende, C. A., & Martínez, J. (2015). Supercritical CO2 extraction of passion fruit (Passiflora edulis sp.) seed oil assisted by ultrasound. The Journal of Supercritical Fluids, 104, 183-192. doi:10.1016/j.supflu.2015.06.006Eric, K., Raymond, L. V., Huang, M., Cheserek, M. J., Hayat, K., Savio, N. D., … Zhang, X. (2013). Sensory attributes and antioxidant capacity of Maillard reaction products derived from xylose, cysteine and sunflower protein hydrolysate model system. Food Research International, 54(2), 1437-1447. doi:10.1016/j.foodres.2013.09.034Sun, Y., Wei, L., Wang, J., Bi, J., Liu, Z., Wang, Y., & Guo, Z. (2010). Optimization of supercritical fluid extraction of saikosaponins from Bupleurum falcatum
with orthogonal array design. Journal of Separation Science, 33(8), 1161-1166. doi:10.1002/jssc.200900529Chen, Y., Xie, M.-Y., & Gong, X.-F. (2007). Microwave-assisted extraction used for the isolation of total triterpenoid saponins from Ganoderma atrum. Journal of Food Engineering, 81(1), 162-170. doi:10.1016/j.jfoodeng.2006.10.01
La generación de conocimiento para los procesos curriculares: un proceso de formación de cuadros
Informe final de un proyecto de gestión del conocimiento vinculado con la formación de cuadros para los procesos curriculares. Integra el conjunto de experiencias sistematizadas en torno al proceso de intervención del proyecto; dichas experiencias se organizan en cuatro capítulos. En el primero, se presenta el planteamiento del problema, se describen las problemáticas de los procesos curriculares y la habilitación académica, así como los propósitos y finalidades desde la gestión del conocimiento. En el segundo, se describe el marco contextual en el que se desarrolló el proyecto; dicha descripción se realiza desde los planos universitarios y del programa académico donde ocurrió la intervención. En este mismo capítulo, se entretejen los marcos teóricos provenientes de la gestión del conocimiento y de los procesos curriculares. En el tercer capítulo, se plantea el plan de trabajo y se integran cada una de las etapas para el desarrollo del proyecto. En el cuarto, se describe el desarrollo del proceso, se integran los resultados de la construcción de la comunidad de práctica, del mapeo del conocimiento y uso del conocimiento. Dichos resultados se analizan desde la teoría de la gestión del conocimiento con la intención de que las experiencias de este proyecto contribuyan a la conformación de un campo teórico necesario
Nuevas técnicas de adquisición y tratamiento de imágenes para el desarrollo de la instrumentación biomédica: Impacto social en el sector salud
En la actualidad, instituciones de carácter gubernamental y privado ofrecen financiamiento económico en investigaciones cien-tíficas y tecnológicas dedicadas a la mejora de las áreas de mayor impacto en la sociedad, donde la salud es una de estas. Aunque la salud también está relacionada con el estado de completo bienes-tar físico/mental, y no solamente a la ausencia de afecciones o en-fermedades, aquí centraremos la discusión en la investigación relacionada con las enfermedades humanas. En este campo, algu-nas instituciones gubernamentales han establecido áreas priorita-rias de salud entre las cuales el cáncer es una de ellas. El cáncer es una de las enfermedades que tiene un gran impacto en la co-munidad en términos de morbilidad, mortalidad y costos. Por ejemplo en Colombia, en el año 2006, 13,9% de las defunciones en hombres y 19,3% de las muertes en mujeres fueron por cáncer (Piñeros et al., 2011)
La innovación curricular y los académicos en la universidad pública estatal mexicana: procesos de Incorporación a sus prácticas
La presente investigación muestra los resultados de un estudio con académicos coordinadores de academias en una Universidad Publica Estatal, donde se busca identificar e interpretar el proceso de incorporación de las innovaciones curriculares a las prácticas educativas, así como el sentido que subyace y las formas que la innovación va obteniendo en el quehacer cotidiano.
Dentro del proceso de investigación se establece un marco teórico y contextual a nivel nacional de las políticas que se han implementado respecto a la innovación educativa y curricular. Se establece un proceso de revisión teórica con base a la teoría de Pierre Bourdieu, para construir un conjunto de categorías apreciativas.
Al final se encuentran resultados categoriales que pueden ser usados en otros contextos para identificar, analizar y generar estrategias que generen mejores formas de incorporación a la práctica profesional los procesos de innovación.ITESO, A. C
What determines adult cognitive skills?: Impacts of preschooling, schooling, and post-schooling experiences in Guatemala
"Most investigations into the importance and determinants of adult cognitive skills assume that (1) they are produced primarily by schooling, and (2) schooling is statistically predetermined or exogenous. This study uses longitudinal data collected in Guatemala over 35 years to investigate production functions for adult cognitive skills—that is, reading-comprehension skills and nonverbal cognitive skills—as being dependent on behaviorally determined preschooling, schooling, and post-schooling experiences. We use an indicator of whether the child was stunted (child height-for-age Z-scoreHuman capital, cognitive skills, Stunting, work experience, Development, Education, Gender, Health and nutrition,
Lithium-doped silk fibroin films for application in electrochromic devices
Silk fibroin (SF) is a commonly available natural biopolymer produced in specialized glands of arthropods,
with a long history of use in textile production and also in health cares. The exceptional intrinsic properties
of these fibers, such as self-assembly, machinability, biocompatibility, biodegradation or non-toxicity, offer a
wide range of exciting opportunities [1].
It has long been recognized that silk can be a rich source of inspiration for designing new materials with
tailored properties, enhanced performance and high added value for targeted applications, opening exciting
new prospects in the domain of materials science and related technological fields, including bio-friendly
integration, miniaturization and multifunctionalization. In recent years it has been demonstrated that fibroin
is an excellent material for active components in optics and photonics devices. Progress in new technological
fields such as optics, photonics and electronics are emerging [2,3].
The incorporation of polymer electrolytes as components of various devices (advanced batteries, smart
windows, displays and supercapacitors) offers significant advantages with respect to traditional electrolytes,
including enhanced reliability and improved safety. SF films are particularly attractive in this context. They
have near-perfect transparency across the VIS range, surface flatness (together with outstanding mechanical
robustness), ability to replicate patterned substrates and their thickness may be easily tailored from a few
nanometers to hundreds of micrometers through spin-casting of a silk solution into subtract. Moreover,
fibroin can be added to other biocomponents or salts in order to modify the biomaterial properties leading to
optimized and total different functions.
Preliminary tests performed with a prototype electrochromic device (ECD) incorporating SF films doped
with lithium triflate and lithium tetrafluoroborate (LiTFSI and LiBF4, respectively) as electrolyte and WO3 as
cathodic electrochromic layer, are extremely encouraging. Aiming to evaluate the performance of the ion
conducting SF membranes doped with LiTFSI and LiBF4 (SF-Li), small ECDs with
glass/ITO/WO3/SF-Li/CeO2-TiO2/ITO/glass configuration were assembled and characterized. The device
exhibited, after 4500 cycles, the insertion of charge at -3.0 V reached –1.1 mC.cm-2
in 15 s. After 4500 cycles
the window glass-staining, glass/ITO/WO3/Fibrin-Li salts electrolyte/CeO2-TiO2/ITO/glass configuration
was reversible and featured a T 8 % at λ = 686 n
Minimal Algorithmic Information Loss Methods for Dimension Reduction, Feature Selection and Network Sparsification
We introduce a family of unsupervised, domain-free, and (asymptotically)
model-independent algorithms based on the principles of algorithmic probability
and information theory designed to minimize the loss of algorithmic
information, including a lossless-compression-based lossy compression
algorithm. The methods can select and coarse-grain data in an
algorithmic-complexity fashion (without the use of popular compression
algorithms) by collapsing regions that may procedurally be regenerated from a
computable candidate model. We show that the method can preserve the salient
properties of objects and perform dimension reduction, denoising, feature
selection, and network sparsification. As validation case, we demonstrate that
the method preserves all the graph-theoretic indices measured on a well-known
set of synthetic and real-world networks of very different nature, ranging from
degree distribution and clustering coefficient to edge betweenness and degree
and eigenvector centralities, achieving equal or significantly better results
than other data reduction and some of the leading network sparsification
methods. The methods (InfoRank, MILS) can also be applied to applications such
as image segmentation based on algorithmic probability.Comment: 23 pages in double column including Appendix, online implementation
at http://complexitycalculator.com/MILS
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