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The Politics of Blood
In: Aztlán: international journal of Chicano studies research, Band 28, Heft 1, S. 39-74
In The Rag Doll Plagues ( 1992), Alejandro Morales employs the epidemic as a metaphor for sociocultural transformations initiated with the conquest of the Americas and continuing into the twenty-first century. The present essay centers on the trope of blood-in terms of the representation of plagues and the possibilities ofmiscegenation- in order to show how The Rag Doll Plagues highlights the fear of intercultural contact and the shortcomings of concepts such as mestizaje to resolve social inequalities, advocating instead a multicultural agenda able to address the socioeconomic complexities of contemporary society. Morales's assessment of different forms of transculturation is germane to current debates on cultural hybridity, issues of race and class, and the use of science and technology as forms of social control.
Factores socioeconómicos asociados al rendimiento académico de estudiantes universitarios
In: Dilemas contemporáneos: Educación, Política y Valores: Contemporary dilemmas: Education, Politics and Values
ISSN: 2007-7890
Este estudio observa si existe asociación entre el capital familiar de los estudiantes y algunos indicadores centrales de su formación profesional o que incidan en la misma, como la trayectoria escolar universitaria, el examen de ingreso a la educación superior EXANI-II, el promedio de bachillerato, y la reprobación en la universidad y el bachillerato. En total, 420 estudiantes de la UPSIN fueron contemplados, pero participaron 314. Se utilizó el análisis estadístico Rho de Spearman. Existe asociación entre el capital familiar de los estudiantes y la trayectoria escolar universitaria y el examen de ingreso a la educación superior. Las desventajas de los estudiantes vulnerables pueden estar impidiendo el acceso a la universidad y además el logro de mejores trayectorias escolares universitarias.
Aproximación al discurso episcopal en torno a la familia (el Concilio Vaticano II, y al episcopado latinoamericano y mexicano)
In: Secuencia: revista de historia y ciencias sociales, Heft 41, S. 095
ISSN: 2395-8464
<p>Se parte de la idea de que existe una pluralidad discursiva en el interior de la Iglesia católica, la cual necesita ser estudiada para comprender, en lo posible, cómo funcionan las propuestas de dicha institución . A partir de ahí, se ensaya un breve acercamiento al concepto de familia planteado en el discurso episcopal de algunos documentos, durante y poco después del Concilio Vaticano II</p>
Graph Similarity through Entropic Manifold Alignment
In this paper we decouple the problem of measuring graph similarity into two sequential steps. The first step is the linearization of the quadratic assignment problem (QAP) in a low-dimensional space, given by the embedding trick. The second step is the evaluation of an information-theoretic distributional measure, which relies on deformable manifold alignment. The proposed measure is a normalized conditional entropy, which induces a positive definite kernel when symmetrized. We use bypass entropy estimation methods to compute an approximation of the normalized conditional entropy. Our approach, which is purely topological (i.e., it does not rely on node or edge attributes although it can potentially accommodate them as additional sources of information) is competitive with state-of-the-art graph matching algorithms as sources of correspondence-based graph similarity, but its complexity is linear instead of cubic (although the complexity of the similarity measure is quadratic). We also determine that the best embedding strategy for graph similarity is provided by commute time embedding, and we conjecture that this is related to its inversibility property, since the inverse of the embeddings obtained using our method can be used as a generative sampler of graph structure. ; The work of the first and third authors was supported by the projects TIN2012-32839 and TIN2015-69077-P of the Spanish Government. The work of the second author was supported by a Royal Society Wolfson Research Merit Award.
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Análisis del desempeño docente y su influencia en el proceso de interaprendizaje de los estudiantes del primer año militar del curso de Aspirantes a Soldados, promoción 2012-2014, en la Escuela de Formación de Soldados del Ejército Vencedores del Cenepa. Propuesta alternativa
El desempeño docente en el aula es un factor determinante para lograr un aprendizaje significativo y duradero en los estudiantes. De allí que es imperativo que se realice un análisis al desempeño de los maestros para llegar a determinar las falencias y dificultades que se presentan durante el desarrollo de las actividades académica, esto con la finalidad de proponer un plan de capacitación que contribuya de manera significativa a mejorar la labor docente y sobre todo lograr que el proceso de interaprendizaje se desarrolle de manera activa y participativa, teniendo como ejes la investigación y el trabajo en equipo, aspectos que no solo facilitan un ambiente propicio para aprender, sino que permiten elevar la calidad educativa en la institución. Para obtener la información se aplicó encuestas al personal docente y estudiantes; obteniéndose como resultado que es necesario mejorar el desempeño de los docentes; por lo tanto se propone un plan de capacitación en diferentes temáticas cuyo propósito fundamental es mejorar su desempeño y de esta manera propiciar un ambiente óptimo para el desarrollo del proceso de interaprendizaje.
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Heat diffusion: thermodynamic depth complexity of networks
In this paper we use the Birkhoff–von Neumann decomposition of the diffusion kernel to compute a polytopal measure of graph complexity. We decompose the diffusion kernel into a series of weighted Birkhoff combinations and compute the entropy associated with the weighting proportions (polytopal complexity). The maximum entropy Birkhoff combination can be expressed in terms of matrix permanents. This allows us to introduce a phase-transition principle that links our definition of polytopal complexity to the heat flowing through the network at a given diffusion time. The result is an efficiently computed complexity measure, which we refer to as flow complexity. Moreover, the flow complexity measure allows us to analyze graphs and networks in terms of the thermodynamic depth. We compare our method with three alternative methods described in the literature (Estrada's heterogeneity index, the Laplacian energy, and the von Neumann entropy). Our study is based on 217 protein-protein interaction (PPI) networks including histidine kinases from several species of bacteria. We find a correlation between structural complexity and phylogeny (more evolved species have statistically more complex PPIs). Although our methods outperform the alternatives, we find similarities with Estrada's heterogeneity index in terms of network size independence and predictive power. ; F.E. and M.L. are funded by Project No. TIN2008-04416 of the Spanish Government. E.R.H. is funded by the EU FET Project SIMBAD and a Royal Society Wolfson Research Merit Award.
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Aerial obstacle detection with 3D mobile devices
In this paper, we present a novel approach for aerial obstacle detection (e.g. branches or awnings) using a 3D smartphone in the context of the visually impaired (VI) people assistance. This kind of obstacles are especially challenging because they cannot be detected by the walking stick or the guide dog. The algorithm captures the 3D data of the scene through stereo vision. To our knowledge, this is the first work that presents a technology able to obtain real 3D measures with smartphones in real time. The orientation sensors of the device (magnetometer and accelerometer) are used to approximate the walking direction of the user, in order to look for the obstacles only in such direction. The obtained 3D data are compressed and then linearized for detecting the potential obstacles. Potential obstacles are tracked in order to accumulate enough evidence to alert the user only when a real obstacle is found. In the experimental section, we show the results of the algorithm in several situations using real data and helped by VI users. ; J.M. Sáez and M.A. Lozano are supported by the University of Alicante research grant GRE10-21. F. Escolano is supported by the project TIN2012-32839 of the Spanish Government.
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Network embedding from the line graph: Random walkers and boosted classification
In this paper, we propose to embed edges instead of nodes using state-of-the-art neural/factorization methods (DeepWalk, node2vec, NetMF). These methods produce latent representations based on co-ocurrence statistics by simulating fixed-length random walks and then taking bags-of-vectors as the input to the Skip Gram Learning with Negative Sampling (SGNS). We commence by expressing commute times embedding as matrix factorization, and thus relating this embedding to those of DeepWalk and node2vec. Recent results showing formal links between all these methods via the spectrum of graph Laplacian, are then extended to understand the results obtained by SGNS when we embed edges instead of nodes. Since embedding edges is equivalent to embedding nodes in the line graph, we proceed to combine both existing formal characterizations of the line graphs and empirical evidence in order to explain why this embedding dramatically outperforms its nodal counterpart in multi-label classification tasks. ; M.A. Lozano, M. Curado and F. Escolano are funded by the project RTI2018-096223-B-I00 of the Spanish Government.
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Dirichlet densifiers for improved commute times estimation
In this paper, we develop a novel Dirichlet densifier that can be used to increase the edge density in undirected graphs. Dirichlet densifiers are implicit minimizers of the spectral gap for the Laplacian spectrum of a graph. One consequence of this property is that they can be used improve the estimation of meaningful commute distances for mid-size graphs by means of topological modifications of the original graphs. This results in a better performance in clustering and ranking. To do this, we identify the strongest edges and from them construct the so called line graph, where the nodes are the potential q −step reachable edges in the original graph. These strongest edges are assumed to be stable. By simulating random walks on the line graph, we identify potential new edges in the original graph. This approach is fully unsupervised and it is both more scalable and robust than recent explicit spectral methods, such as the Semi-Definite Programming (SDP) densifier and the sufficient condition for decreasing the spectral gap. Experiments show that our method is only outperformed by some choices of the parameters of a related method, the anchor graph, which relies on pre-computing clusters representatives, and that the proposed method is effective on a variety of real-world datasets. ; M. Curado, F. Escolano and M.A. Lozano are funded by the projects TIN2015-69077-P and BES2013-064482 of the Spanish Government.
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An efficient, dense and long-range marker system for the guidance of the visually impaired
In this paper, we address the problem of making a mobile/smartphone camera sensitive to distant fiducial markers. To this end, we carefully design a novel visual marker that is both dense and readable from large distances. The main novelty of the proposed marker is the combination of a quaternary color-based coding system with robust methods for reading the color patterns included in each frame once it is detected. These patterns include a CRC whose length grows linearly, whereas that of the message grows quadratically. Our experiments show that the proposed bundle marker-vision algorithm outperforms the alternatives in terms of distance and angle and also that it is very robust to changes in lighting conditions, thus making it a good intelligent system for guiding people with visual impairments in their day to day use of public transportation systems. ; This work is partially supported by the projects TIN2015-69077-P and RTI2018-096223-B-I00 of the Spanish Government and the grant INFO2016.08.ID+I.0019 from Instituto de Fomento de la Región de Murcia.
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Estudio de género sobre la intención emprendedora en la universidad tecnológica El Retoño, México
In: Telos: revista de estudios interdisciplinarios en ciencias sociales, Band 24, Heft 3, S. 749-769
ISSN: 2343-5763
El estudio tiene como objetivo conocer la Intención Emprendedora (IE) por género de los alumnos de la Universidad Tecnológica el Retoño, para determinar qué tan efectivas están siendo las estrategias para incentivarla. El emprendimiento es considerado como fuente de desarrollo económico y social, actualmente el número de mujeres emprendedoras va en aumento, investigaciones han demostrado que los estudios universitarios predominan en las mujeres que deciden emprender. Es por esto que en el presente trabajo se estudia la intención emprendedora de los estudiantes universitarios en dos puntos del tiempo cuatrimestre septiembre-diciembre 2019 (propedéutico) y cuatrimestre mayo-agosto 2020, mediante la aplicación de un instrumento, centrando la atención en la intención emprendedora por género. Utilizando la prueba no paramétrica de Friedman para medidas repetidas y la aproximación de F de Fisher para observaciones multivariadas. Los resultados obtenidos mostraron que la IE de las mujeres es mayor que la de los hombres, tanto en el cuatrimestre septiembre-diciembre 2019 como en el cuatrimestre mayo-agosto 2020, así mismo la IE de las mujeres se mantuvo en el mismo nivel durante los 2 periodos estudiados, con lo cual se puede inferir que la percepción de las mujeres universitarias para emprender está cambiando y va en aumento.
A temporal regulatory mechanism controls the different contribution of endoplasmic reticulum and plastidial ω-3 desaturases to trienoic fatty acid content during leaf development in soybean (Glycine max cv Volania)
10 Págs., 7 Figs. Available online 5 August 2013. The definitive version is available at: http://www.sciencedirect.com/science/journal/00319422 ; We analyzed the molecular mechanism controlling ω-3 fatty acid desaturases during seed germination and leaf development in soybean. During germination, soybean seeds were characterized by a high 18:2Δ9,12 level (more than 50%) and reduced 18:3Δ9,12,15 content (10%). Interestingly, transcripts from all endoplasmic reticulum (GmFAD3A and GmFAD3B) and plastidial (GmFAD7-1/GmFAD7-2 or GmFAD8-1/GmFAD8-2) desaturase genes were detected during seed germination. Upon germination, soybean trifoliate leaf development was accompanied by an increase in linolenic acid (18:3Δ9,12,15). Our data showed that transcripts corresponding to the endoplasmic reticulum ω-3 desaturases GmFAD3A and GmFAD3B decreased with leaf development. No changes in the expression profile of the plastidial ω-3 desaturases GmFAD7-1 and GmFAD7-2 genes were detected. On the contrary, GmFAD8-2 transcript levels increased while GmFAD8-1 transcripts decreased during leaf development. Given this expression profile, our data suggested the existence of a temporal regulatory mechanism controlling ω-3 desaturases during leaf development in which the endoplasmic reticulum ω-3 desaturases would be more important in young leaves while plastidial ω-3 desaturases might contribute to 18:3Δ9,12,15 production in mature leaves. Photosynthetic cell cultures showed 18:3Δ9,12,15 levels similar to those from leaves. No changes in the 18:3Δ9,12,15 content or expression of the ω-3 desaturase genes were detected along the cell culture cycle. A comparison of our data with those available in Arabidopsis or wheat suggested that the regulatory mechanism controlling the expression and activity of both endoplasmic reticulum and plastidial desaturases during leaf development might differ among plant species. ; This work was supported by the Consejo Superior de Investigaciones Científicas (CSIC, Grant PIE 2006 4-OI-004) to M.A. and Spanish Ministry of Science and Innovation (Grants AGL2008-00733 and AGL2011-23574) to R.P. B.L. and A.R. were recipient of a predoctoral fellowship from the JAE-CSIC program and V.A. was recipient of a predoctoral fellowship from the Aragón Government. ; Peer reviewed
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The GmFAD7 gene family from soybean: identification of novel genes and tissue-specific conformations of the FAD7 enzyme involved in desaturase activity
40 Pag., 8 Fig. The definitive version is available at: http://jxb.oxfordjournals.org/ ; The FAD7 gene encodes a ω3 fatty acid desaturase which catalyses the production of trienoic fatty acids (TAs) in plant chloroplasts. A novel GmFAD7 gene (named GmFAD7-2) has been identified in soybean, with high homology to the previously annotated GmFAD7 gene. Genomic sequencing analysis together with searches at the soybean genome database further confirmed that both GmFAD7 genes were located in two different loci within the soybean genome, suggesting that the soybean ω3 plastidial desaturase FAD7 is encoded by two different paralogous genes. Both GmFAD7-1 and GmFAD7-2 genes were expressed in all soybean tissues examined, displaying their highest mRNA accumulation in leaves. This expression profile contrasted with GmFAD3A and GmFAD3B mRNA accumulation, which was very low in this tissue. These results suggested a concerted control of plastidial and reticular ω3 desaturase gene expression in soybean mature leaves. Analysis of GmFAD7 protein distribution in different soybean tissues showed that, in mature leaves, two bands were detected, coincident with the higher expression level of both GmFAD7 genes and the highest 18:3 fatty acid accumulation. By contrast, in seeds, where FAD7 activity is low, specific GmFAD7 protein conformations were observed. These GmFAD7 protein conformations were affected in vitro by changes in the redox conditions of thiol groups and iron availability. These results suggest the existence of tissue-specific post-translational regulatory mechanisms affecting the distribution and conformation of the FAD7 enzymes related with the control of its activity. ; This work was supported by the Aragón Government (PIP 140/2008) and the Spanish Ministry of Science and Innovation (Grants BFU2005-07422-CO2-01 and AGL2008-00733). VA was the recipient of a predoctoral fellowship from the Aragón Government. BL was the recipient of a predoctoral fellowship from the JAE-CSIC Program. ; Peer reviewed
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Influence of meteorological phenomena on worldwide aircraft accidents in the period 1967-2010
This is the pre-peer reviewed version of the following article: Mazon, J., Rojas, J. I., Lozano, M., Pino, D., Prats, X. and Miglietta, M. M. (2017), Influence of meteorological phenomena on worldwide aircraft accidents, 1967–2010. Met. Apps. doi:10.1002/met.1686, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/met.1686/abstract. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; Based on the information available in databases from relevant national and international organizations from 1967 to 2010, an Aviation Weather Accidents Database (AWAD) was built. According to the AWAD, the weather is the primary cause in a growing percentage of annual aircraft accidents: from about 40% in 1967 to almost 50% in 2010. While the absolute number of fatalities and injured people due to aircraft accidents has decreased significantly, the percentage of fatalities and injured people in accidents attributed to the weather shows a slight increase in the studied period. The influence of turbulence, clear air turbulence, wind shear, low visibility, rain, icing, snow and storms on aircraft accidents was analysed, considering the different phases of flight, the meteorological seasons of the year and the spatial distribution over four zones of the Earth. These zones were defined following meteorological and climatological criteria, instead of using the typical political criteria. A major part of the accidents and accidents attributed to the weather occur in latitudes between 12º and 38º in both hemispheres. It is concluded that actions aimed at reducing the risk associated with low visibility, rain and turbulence, in this order, should have priority to achieve the most significant improvements in air transport safety. ; Postprint (author's final draft)
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