francisco sanchez - Academia.edu (original) (raw)

Papers by francisco sanchez

PLoS ONE, 2014

To what extent do cholesterol-rich lipid platforms modulate the supramolecular organization of th... more To what extent do cholesterol-rich lipid platforms modulate the supramolecular organization of the nicotinic acetylcholine receptor (AChR)? To address this question, the dynamics of AChR particles at high density and its cholesterol dependence at the surface of mammalian cells were studied by combining total internal reflection fluorescence microscopy and singleparticle tracking. AChR particles tagged with a monovalent ligand, fluorescent a-bungarotoxin (aBTX), exhibited two mobile pools: i) a highly mobile one undergoing simple Brownian motion (16%) and ii) one with restricted motion (,50%), the rest being relatively immobile (,44%). Depletion of membrane cholesterol by methyl-a-cyclodextrin increased the fraction of the first pool to 22% and 33% after 15 and 40 min, respectively; the pool undergoing restricted motion diminished from 50% to 44% and 37%, respectively. Monoclonal antibody binding results in AChR crosslinking-internalization after 2 h; here, antibody binding immobilized within minutes ,20% of the totally mobile AChR. This proportion dramatically increased upon cholesterol depletion, especially during the initial 10 min (83.3%). Thus, antibody crosslinking and cholesterol depletion exhibited a mutually synergistic effect, increasing the average lifetime of cell-surface AChRs,10 s to ,20 s. The instantaneous (microscopic) diffusion coefficient D 2-4 of the AChR obtained from the MSD analysis diminished from ,0.001 mm 2 s 21 to ,0.0001-0.00033 mm 2 s 21 upon cholesterol depletion, ,30% of all particles falling into the stationary mode. Thus, muscle-type AChR exhibits heterogeneous motional regimes at the cell surface, modulated by the combination of intrinsic (its supramolecular organization) and extrinsic (membrane cholesterol content) factors.

IEEE EDUCON 2010 Conference, 2010

In this paper, a review of the educational research that is being developed in Spain is realized ... more In this paper, a review of the educational research that is being developed in Spain is realized in the areas of Electrical, Electronics, Telecommunications and Informatics through the works presented to the prizes CESEI (Spanish Chapter of the Education Society of the IEEE) in his three editions. There are two categories of candidates to the prizes, one for the Doctoral Thesis and the second for the Final Degree (or Master) Projects. An analysis of the working areas, the subjects covered as well as the conferences and journals where the results are published has been done. The main goal of this paper is to have a general vision about the work done in such areas of educational research in Spain that will be very interesting for academic staff and researchers.

IEEE EDUCON 2010 Conference, 2010

This paper shows the activities of the Technical Committee of the CESEI (Spanish Chapter of the I... more This paper shows the activities of the Technical Committee of the CESEI (Spanish Chapter of the IEEE Education Society). The CESEI is focused on the development of the education in engineering, mainly Electric and Computer Engineering, and the Technical Committee is devoted to contribute to its awareness and dissemination. As in other interdisciplinary fields, the engineering education field involves several

IEEE EDUCON 2010 Conference, 2010

This paper shows the results of a survey performed in Spain about the different functionalities o... more This paper shows the results of a survey performed in Spain about the different functionalities of e-learning platforms. This survey was filled in by a group of teachers, experts in Engineering Education along all Spain, through the Spanish Chapter of the IEEE Education Society. The paper shows the opinion on several aspects about the e-learning functionalities, such as knowledge level, usage level, usefulness, etc., as well as the most used platforms. One of the objectives of this work is to create a reflexive debate in the international community about the e-Learning platform use.

Molecules, 2010

The catalytic effect of micelles, polymers (such as DNA, polypeptides) and nanoparticles, saturab... more The catalytic effect of micelles, polymers (such as DNA, polypeptides) and nanoparticles, saturable receptors (cyclodextrins and calixarenes) and more complex systems (mixing some of the above mentioned catalysts) have been reviewed. In these microheterogeneous systems the observed changes in the rate constants have been rationalized using the Pseudophase Model. This model produces equations that can be derived from the Brönsted equation, which is the basis for a more general formulation of catalytic effects, including electrocatalysis. When, in the catalyzed reaction one of the reactants is in the excited state, the applicability (at least formally) of the Pseudophase Model occurs only in two limiting situations: the lifetime of the fluorophore and the distributions of the quencher and the probe are the main properties that define the different situations.

Journal of Mathematical Economics, 2002

In this paper we study the problem of distributing a given amount among a set of agents, accordin... more In this paper we study the problem of distributing a given amount among a set of agents, according to their performance in a set of issues. In contrast with multi-issue allocation situations where each agent claims some of the amount, in this model the distribution must take into account how each agent behaves on some issues. We characterize a family of solutions for this problem using the well-known additivity, equal treatment and efficiency properties, adapting them to our context. If we want a solution that satisfies two additional properties, reduction and proportional, another problem arises: we need to look for a system of prices for a unity of each issue. Also, we apply classical bargaining theory techniques for the problem and some results are shown.