The Professor-Tutor of Teaching "Prácticum" Like Professional User of Media

En este artículo presentamos un somero resumen de los resultados más interesantes obtenidos en una tesis doctoral denominada “Uso de los medios en el Prácticum de Magisterio”. Estos versan sobre la utilización que hacen de los medios y recursos los profesores-tutores durante el periodo en el que el estudiante de magisterio esta realizando las prácticas bajo su asesoría y supervisión.This article shows a brief resume about the more interesting results gotten in a doctoral thesis titled: “The use of the technological and traditional resources during the teacher training Practicum”. In this text, we analyse the data obtain about the use of this resources by the tutor-teachers when they are tutoring student-teachers

Influencia de la expropiación forzosa en la disponibilidad de terrenos para la ejecución de obras de modernización de regadíos

La evolución de la economía del país, ha hecho que los tipos de interés hayan disminuido de manera continuada en los últimos años. El hecho de que la determinación del valor de expropiación desde el año 2.007 se lleve a cabo mediante capitalización de rentas y que, por lo tanto, el valor de indemnización dependa del tipo de interés, ha ocasionado un efecto económico difícil para las partes beneficiarias en una expropiación. En este trabajo se estudia la evolución de la normativa, se cuantifican los resultados para el caso de una finca concreta de una explotación de algodón de regadío en el valle del Guadalquivir y se analizan los resultados. En el estudio puede observarse que en los últimos ocho años, el valor de mercado de la tierra ha seguido una tendencia a la baja. Por el contrario, el valor de indemnización por expropiación de la misma se ha disparado, lo que hace inviable a las comunidades de regantes la participación en la modernización de regadíos, así como a la Administración la aplicación del Plan Hidrológico Nacional o Plan Nacional de Regadíos. Estas circunstancias han hecho que, en octubre de 2.015 (Ley de carreteras) y noviembre de 2.015 (Texto refundido de Ley de Suelo), la legislación haya intentado paliar la situación, aunque sigue siendo insuficiente. Por ello se proponen algunas medidas a modo de conclusión al final del trabajo.The evolution of the country's economy has made that interest rates have decreased continuously in recent years. The fact that since the year 2007 the determination of the value of expropriation is being carried out through revenue capitalization, in which the indemnification value depends on the interest rate, has caused a difficult economic impact in the recipient parties of an expropriation. In this paper we study the evolution of the expropriation regulations as well as the assessment of the amount of money corresponding to the expropriation of a farm dedicated the production of cotton in the Guadalquivir valley. In the study it can be seen that over the last eight years the market value of the land has followed a downward trend. On the other hand, the value of compensation for land expropriation has been triggered, making infeasible to the irrigation communities their participation in the modernization of the irrigation systems and hinders the Administration the implementation of the National Hydrological Plan or the National Irrigation Plan. These circumstances have led the Government to try to alleviate the situation with new regulations (road act of October 2015 and revised text of law of soil of November 2015) which remain insufficient. Therefore some legislative proposals are given as conclusions at the end of this work

Survival, differentiation, and neuroprotective mechanisms of human stem cells complexed with neurotrophin-3-releasing pharmacologically active microcarriers in an ex vivo model of parkinson’s disease

© AlphaMed Press 2015. Stem cell-based regenerative therapies hold great potential for the treatment of degenerative disorders such as Parkinson’s disease (PD). We recently reported the repair and functional recovery after treatment with human marrow-isolated adult multilineage inducible (MIAMI) cells adhered to neurotrophin-3 (NT3) releasing pharmacologically active microcarriers (PAMs) in hemiparkinsonian rats. In order to comprehend this effect, the goal of the present work was to elucidate the survival, differentiation, and neuroprotective mechanisms of MIAMI cells and human neural stem cells (NSCs), both adhering to NT3-releasing PAMs in an ex vivo organotypic model of nigrostriatal degeneration made from brain sagittal slices. It was shown that PAMs led to a marked increase in MIAMI cell survival and neuronal differentiation when releasing NT3. A significant neuroprotective effect of MIAMI cells adhering to PAMs was also demonstrated. NSCs barely had a neuroprotective effect and differentiated mostly into dopaminergic neuronal cells when adhering to PAM-NT3. Moreover, those cells were able to release dopamine in a sufficient amount to induce a return to baseline levels. Reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay analyses identified vascular endothelial growth factor (VEGF) and stanniocalcin-1 as potential mediators of the neuroprotective effect of MIAMI cells and NSCs, respectively. It was also shown that VEGF locally stimulated tissue vascularization, which might improve graft survival, without excluding a direct neuroprotective effect of VEGF on dopaminergic neurons. These results indicate a prospective interest of human NSC/PAM and MIAMI cell/PAM complexes in tissue engineering for PD.Spanish Ministry of Economy and Competitiveness (Grant SAF2010-17167), a grant from the Comunidad de Madrid (Grant S2011-BMD-2336), and Instituto de Salud Carlos III (Redes Tematicas de Investigacion Cooperativa en Salud RD12/0019/0013) to A.M.S.Peer Reviewe

A finite element-based machine learning approach for modeling the mechanical behavior of the breast tissues under compression in real-time

[EN] This work presents a data-driven method to simulate, in real-time, the biomechanical behavior of the breast tissues in some image-guided interventions such as biopsies or radiotherapy dose delivery as well as to speed up multimodal registration algorithms. Ten real breasts were used for this work. Their deformation due to the displacement of two compression plates was simulated off-line using the finite element (FE) method. Three machine learning models were trained with the data from those simulations. Then, they were used to predict in real-time the deformation of the breast tissues during the compression. The models were a decision tree and two tree-based ensemble methods (extremely randomized trees and random forest). Two different experimental setups were designed to validate and study the performance of these models under different conditions. The mean 3D Euclidean distance between nodes predicted by the models and those extracted from the FE simulations was calculated to assess the performance of the models in the validation set. The experiments proved that extremely randomized trees performed better than the other two models. The mean error committed by the three models in the prediction of the nodal displacements was under 2 man, a threshold usually set for clinical applications. The time needed for breast compression prediction is sufficiently short to allow its use in real-time (< 0.2 s).This work has been funded by the Spanish Ministry of Economy and Competitiveness (MINECO) through research projects TIN2014-52033-R and DPI2013-40859-R with the support of European FEDER funds.Martínez Martínez, F.; Rupérez Moreno, MJ.; Martínez-Sober, M.; Solves Llorens, JA.; Lorente, D.; Serrano-Lopez, A.; Martinez-Sanchis, S.... (2017). A finite element-based machine learning approach for modeling the mechanical behavior of the breast tissues under compression in real-time. Computers in Biology and Medicine. 90:116-124. https://doi.org/10.1016/j.compbiomed.2017.09.019S1161249

The stellar spheroid, the disk, and the dynamics of the cosmic web

Astrophysical Journal Letters 800.2 (2015): L30 reproduced by permission of the AASModels of the advanced stages of gravitational instability predict that baryons that form the stellar populations of current galaxies at z = 0 displayed a web-like structure at high z, as part of the cosmic web (CW). We explore details of these predictions using cosmological hydrodynamical simulations. When the stellar populations of the spheroid and disk components of simulated late-type galaxies are traced back separately to high zs we found CW-like structures where spheroid progenitors are more evolved than disk progenitors. The distinction between the corresponding stellar populations, as driven by their specific angular momentum content j, can be explained in terms of the CW evolution, extended to two processes occurring at lower z. First, the spheroid progenitors strongly lose j at collapse, which contrasts with the insignificant j loss of the disk progenitors. The second is related to the lack of alignment, at assembly, between the spheroid-to-be material and the already settled proto-disk, in contrast to the alignment of disk-to-be material, in some cases resulting from circumgalactic, disk-induced gravitational torques. The different final outcomes of these low-z processes have their origins in the different initial conditions driven by the CW dynamicsThis work was partially supported by the MICINN and MINECO (Spain) through the grants AYA2009-12792-C03-02, AYA2009-12792-C03-03, and AYA2012-31101 from the PNAyA, as well as by the "Supercomputación y e-Ciencia" Consolider-Ingenio CSD2007-0050 project. A.O. was financially supported through a FPI contract from AYA2009-12792-C03-03 and C.B.B. through a contract from AYA2012-3110

On studying the interaction between different stent models and rabbit tracheal tissue: numerical, endoscopic and histological comparison

Stenting technique is employed worldwide for treating atherosclerotic vessel and tracheal stenosis. Both diseases can be treated by means of metallic stents which present advantages but are affected by the main problem of restenosis of the stented area. In this study we have built a rabbit trachea numerical model and we have analyzed it before and after insertion and opening of two types of commercial stent: a Zilver® FlexTM Stent and a WallStentTM. In experimental parallel work, two types of stent were implanted in 30 New Zealand rabbits divided in two groups of 10 animals corresponding to each stent type and a third group made up of 10 animals without stent. The tracheal wall response was assessed by means of computerized tomography by endoscopy, macroscopic findings and histopathological study 90 days after stent deployment. Three idealized trachea models, one model for each group, were created in order to perform the computational study. The animal model was used to validate the numerical findings and to attempt to find qualitative correlations between numerical and experimental results. Experimental findings such as inflammation, granuloma and abnormal tissue growth, assessed from histomorphometric analyses were compared with derived numerical parameters such as wall shear stress (WSS) and maximum principal stress. The direct comparison of these parameters and the biological response supports the hypothesis that WSS and tensile stresses may lead to a greater tracheal epithelium response within the stented region, with the latter seeming to have the dominant role. This study may be helpful for improving stent design and demonstrates the feasibility offered by in-silico investigated tracheal structural and fluid dynamics

Deciphering the unique structure and acylation pattern of Posidonia oceanica lignin

Copyright © 2020 American Chemical Society. Lignins from different parts of the seagrass Posidonia oceanica-namely sheaths, rhizome, and roots-as well as from fibrous balls from P. oceanica detritus were isolated and thoroughly characterized by pyrolysis coupled with gas chromatography/mass spectrometry, derivatization followed by reductive cleavage, two-dimensional nuclear magnetic resonance spectroscopy, and gel permeation chromatography. The lignins of P. oceanica were enriched in guaiacyl (G) over syringyl (S) units, with S/G ratios ranging from 0.1 (fibrous balls) to 0.5 (rhizome). β-O-4′ ethers and phenylcoumarans were the most abundant lignin substructures, followed by resinols, and minor amounts of dibenzodioxocins and spirodienones. Moreover, all lignins were found to be highly I-Acylated (up to 44% of total units), mainly with p-hydroxybenzoates but also, to a lesser extent, with acetates. The data indicated that this acylation extensively occurred in both G-and S-lignin units, contrary to what happens in palms, poplar, and willow, where p-hydroxybenzoates overwhelmingly appear at the I-position of S-units

Electron-phonon renormalization of the absorption edge of the cuprous halides

Compared to most tetrahedral semiconductors, the temperature dependence of the absorption edges of the cuprous halides (CuCl, CuBr, CuI) is very small. CuCl and CuBr show a small increase of the gap $E_0$ with increasing temperature, with a change in the slope of $E_0$ vs. $T$ at around 150 K: above this temperature, the variation of $E_0$ with $T$ becomes even smaller. This unusual behavior has been clarified for CuCl by measurements of the low temperature gap vs. the isotopic masses of both constituents, yielding an anomalous negative shift with increasing copper mass. Here we report the isotope effects of Cu and Br on the gap of CuBr, and that of Cu on the gap of CuI. The measured isotope effects allow us to understand the corresponding temperature dependences, which we also report, to our knowledge for the first time, in the case of CuI. These results enable us to develop a more quantitative understanding of the phenomena mentioned for the three halides, and to interpret other anomalies reported for the temperature dependence of the absorption gap in copper and silver chalcogenides; similarities to the behavior observed for the copper chalcopyrites are also pointed out.Comment: 14 pages, 5 figures, submitted to Phys. Rev.