Suchergebnisse

En este ensayo, se lleva a cabo una confrontación de dos importantes filósofos y luchadores anti-fascistas que comparten la tesis de que la filosofía de Marx es una "filosofía de la praxis", sin embargo, su reflexión discurre por dos vías: en el caso de Sánchez Vázquez precisando el concepto de praxis y planteando diversas formas de ella como praxis creadora en el arte y la sociedad; problemas de la relación entre ética y política, racionalidad y violencia y en el caso de Gramsci desarrollando su teoría de los intelectuales, el bloque histórico, la hegemonía, nueva concepción de la filosofía, guerra de posiciones, guerra de movimiento, catarsis y otras categorías. Se concluye con la necesidad de dar lugar a una nueva concepción unificadora de la filosofía de la praxis.

Desde sus inicios, el movimiento estudiantil mexicano "#YoSoy132", surgido al calor de la reciente contienda electoral, ubicó como uno de sus objetivos principales la lucha por la democratización de los medios de comunicación.

In the first part of a debate on a book by Victor Flores Olea & Abelardo Marina, A Critique of Globalism. Domination and Liberation in Our Times (Mexico: FCE, 1999), the authors are commended for their well documented & incisive treatment of globalization. Among the many issues discussed in the book, the topics of modern reason & Mexico are examined in detail here. Offered are an extensive diagnosis of globalization & its consequences, along with a search for possible alternatives. J. Sadler

In diesem Artikel wird der Versuch unternommen, zu bestimmen, was das Wesen der lateinamerikanischen Philosophie im 20. Jahrhundert ausmacht, welche sozialen Funktionen sie erfüllt und welche Perspektiven sich ihr bieten. Da mit diesem Anliegen auch die philosophischen Hauptströmungen herangezogen und deren historische Abfolge und damit Fragen der Periodisierung diskutiert werden, vermittelt die Arbeit ein gerafftes Panorama der Philosophiegeschichte in Lateinamerika in diesem Jahrhundert

El agua es un bien escaso e imprescindible para las diferentes actividades del hombre. Los usos del agua generan demandas del recurso hídrico dentro de una cuenca hidrográfica. Así mismo, cada cuenca hidrográfica presenta una oferta hídrica que en ocasiones resulta ser inferior a las demandas de agua y es en esta situación cuando se recurenaobrashidráulicascomoembalses,reservorios,azudes,entreotrosparaatenderalademandaapesarde una limitada oferta hídrica. Los embalses constituyen un elemento esencial para la regulación de los recursos hidráulicos y contribuyen de manera muy significativa al progreso de la humanidad. El presente artículo trata sobre algunos elementos técnicos, económicos, sociales y ambientales que son importantes resaltar en la proyección de un embalse. El propósito es orientar y dar elementos de juicio a la opinión pública en general y recordar dichos elementos especialmente a los tomadores de decisión, en lo que se refiere a la proyección y estudiosdeviabilidadparalaconstruccióndeunembalseendeterminadaregión.Comoestudiodecasoseanaliza la posibilidad de un embalse en el Departamento del Quindío, localizada en la región cafetera de Colombia, situaciónquehageneradodiferentesexpectativaseincertidumbresengranpartedelapoblacióndelaregión.

The combination of light‐emitting diodes (LEDs) and rare earth (RE) phosphors as color‐converting layers comprises the basis of solid‐state lighting. Indeed, most LED lamps include a photoluminescent coating made of phosphor material, i.e., crystalline matrix suitably doped with RE elements, to produce white light from a blue or ultraviolet LED chip. Transparent phosphor‐based films constitute starting materials for new refined emitters that allow different photonic designs to be implemented. Among the different photonic strategies typically employed to tune or enhance emission, surface texturing has proved its versatility and feasibility in a wide range of materials and devices. However, most of the nanofabrication techniques cannot be applied to RE phosphors directly because of their chemical stability or because of their cost. The first monolithic patterned structure of down‐shifting nanophosphors with square arrays of nanoholes with different lattice parameters is reported in this study. It is shown that a low‐cost soft‐nanolithography procedure can be applied to red‐emitting nanophosphors (GdVO4:Eu3+ nanocrystals) to tune their emission properties, attaining a twofold directional enhancement of the emitted light at predesigned emission wavelengths in specific directions. ; This project received funding from the Spanish Ministry of Economy and Competitiveness under grant MAT2017‐88584‐R (AEI/FEDER, UE) and PID2019‐106860GB‐I00 (AEI/FEDER, UE), the excellence program SEV‐2015‐0496, and the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (NANOPHOM, grant agreement no. 715832 and ENLIGHTMENT, grant no. 637116). P.M acknowledges financial support from an FPI contract (2017) of the MICINN (Spain) cofounded by the ESF and the UAB. E.C.O. acknowledges the Spanish Ministry of Universities for the funding through an FPU program (FPU19/00346). ; Peer reviewed

Among the different approaches to humidity sensing available, those based on fluorescent signals are gathering a great deal of attention due to their fast response and versatility of detection and design. So far, all proposals have focused on the use of luminescent probes whose emission is either triggered or inhibited by the presence of water that reacts or alters their chemical environment, hence inducing the signal change. Here, a novel concept in fluorescent humidity sensing based on combining stimuli-responsive photonic resonators with molecular fluorescent probes is introduced. The resonator is assembled from humidity-swellable antimony phosphate nanosheets embedding a planar light-emitting probe, whose emission is dramatically modified by the changes that ambient humidity causes in its photonic environment. Guided by "in silico" optical design of the resonator architecture and subsequent experimental realization, two embodiments of fluorescent photonic humidity sensors featuring turn-on and turn-off detection schemes are presented. The interplay between the luminescent properties of an emitter and its photonic environment implies a fundamental advantage as the emitters are not chemically altered during the detection process. At the same time, it paves the way toward a new generation of photonic humidity sensors which can conveniently be interfaced with common fluorescence detection schemes. ; Financial support granted by the Max Planck Society, the University of Munich (LMU), the Center for NanoScience (CeNS), the Deutsche Forschungsgemeinschaft (DFG) through the Cluster of Excellence Nanosystems Initiative Munich (NIM), the European Research Council under the European Union's Seventh Framework Programme (FP7/2007‐2013)/ERC Grant Agreement No. 307081 (POLIGHT), and the Spanish Ministry of Economy and Competitiveness under grant MAT2014‐54852‐R is gratefully acknowledged. A.J.‐S. acknowledges the Spanish Ministry of Economy and Competitiveness for funding through an FPI program under the project MAT2011‐23593.

The effect of ration size on muscle fatty acid (FA) composition and mRNA expression levels of key regulatory enzymes of lipid and lipoprotein metabolism have been addressed in juveniles of gilthead sea bream fed a practical diet over the course of an 11-week trial. The experimental setup included three feeding levels: (i) full ration until visual satiety, (ii) 70 % of satiation and (iii) 70 % of satiation with the last 2 weeks at the maintenance ration. Feed restriction reduced lipid content of whole body by 30 % and that of fillet by 50 %. In this scenario, the FA composition of fillet TAG was not altered by ration size, whereas that of phospholipids was largely modified with a higher retention of arachidonic acid and DHA. The mRNA transcript levels of lysophosphatidylcholine acyltransferases, phosphatidylethanolamine N-methyltransferase and FA desaturase 2 were not regulated by ration size in the present experimental model. In contrast, mRNA levels of stearoyl-CoA desaturases were markedly down-regulated by feed restriction. An opposite trend was found for a muscle-specific lipoprotein lipase, which is exclusive of fish lineage. Several upstream regulatory transcriptions were also assessed, although nutritionally mediated changes in mRNA transcripts were almost reduced to PPARα and β, which might act in a counter-regulatory way on lipolysis and lipogenic pathways. This gene expression pattern contributes to the construction of a panel of biomarkers to direct marine fish production towards muscle lean phenotypes with increased retentions of long-chain PUFA. Copyright © The Authors 2012. ; The present study was funded by the Spanish MICINN (AQUAFAT, AGL2009-07797, Predictive modelling of flesh FA composition in cultured fish species with different muscle lipid content; AQUAGENOMICS, CSD2007-00002, Improvement of aquaculture production by the use of biotechnological tools) and the European Union (ARRAINA, FP7-KBBE-2011-5-288925, Advanced research initiatives for nutrition and aquaculture) projects. Additional funding was obtained from the 'GeneralitatValenciana' (research grant PROMETEO 2010/006). ; Peer Reviewed

Herein we realize an optical design that optimizes the performance of bifacial solar cells without modifying any of the usually employed components. In order to do so, dielectric scatterers of controlled size and shape have been successfully integrated in the working electrodes of dye-sensitized solar cells (DSSCs), resulting in bifacial devices of outstanding performance. Power conversion efficiencies (PCEs) as high as 6.7% and 5.4% have been attained under front and rear illumination, respectively, which represent a 25% and a 33% PCE enhancement with respect to an 8 mm-thick standard solar cell electrode using platinum as the catalytic material. The remarkable bifacial character of our approach is demonstrated by the high rear/front efficiency ratio attained, around 80%, which is among the largest reported for this sort of device. The proposed optimized design is based on a Monte Carlo approach in which the multiple scattering of light within the cell is fully accounted for. We identified that the spherical shape of the scatterers is the key parameter controlling the angular distribution of the scattering, the most efficient devices being those in which the inclusions provide a narrow forward-oriented angular distribution of the scattered light. ; Funding for the development of the research leading to these results was received from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no. 307081 (POLIGHT) and the Spanish Ministry of Economy and Competitiveness under grant MAT2014-54852-R. JMMM acknowledges the Spanish Ministry of Education, Culture and Sport for the funding through an FPU program. AJS acknowledges the Spanish Ministry of Economy and Competitiveness for funding through an FPI program under the project MAT2011–23593. YL acknowledges the funding from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007-2013/under REA grant agreement no. 622533. ; We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI) ; Peer reviewed

Seven isoproteic and isolipidic semi-purified diets were formulated to assess specific nutrient deficiencies in sulphur amino acids (SAA), n-3 long-chain PUFA (n-3 LC-PUFA), phospholipids (PL), P, minerals (Min) and vitamins (Vit). The control diet (CTRL) contained these essential nutrients in adequate amounts. Each diet was allocated to triplicate groups of juvenile gilthead sea bream fed to satiety over an 11-week feeding trial period. Weight gain of n-3 LC-PUFA, P-Vit and PL-Min-SAA groups was 50, 60-75 and 80-85 % of the CTRL group, respectively. Fat retention was decreased by all nutrient deficiencies except by the Min diet. Strong effects on N retention were found in n-3 LC-PUFA and P fish. Combined anaemia and increased blood respiratory burst were observed in n-3 LC-PUFA fish. Hypoproteinaemia was found in SAA, n-3 LC-PUFA, PL and Vit fish. Derangements of lipid metabolism were also a common disorder, but the lipodystrophic phenotype of P fish was different from that of other groups. Changes in plasma levels of electrolytes (Ca, phosphate), metabolites (creatinine, choline) and enzyme activities (alkaline phosphatase) were related to specific nutrient deficiencies in PL, P, Min or Vit fish, whereas changes in circulating levels of growth hormone and insulin-like growth factor I primarily reflected the intensity of the nutritional stressor. Histopathological scoring of the liver and intestine segments showed specific nutrient-mediated changes in lipid cell vacuolisation, inflammation of intestinal submucosa, as well as the distribution and number of intestinal goblet and rodlet cells. These results contribute to define the normal range of variation for selected biometric, biochemical, haematological and histochemical markers. © 2015 The Authors. ; This study was funded by the European Union (ARRAINA, FP7-KBBE-2011-5-288925, Advanced Research Initiatives for Nutrition and Aquaculture) projects. Additional funding was obtained from the Spanish MINECO (MI2-Fish, AGL2013-48560) and from Generalitat Valenciana (PROMETEO FASE II-2014/085). G. F. B.-L. was a recipient of a Spanish PhD fellowship from the Diputación Provincial de Castellón. ; Peer Reviewed

Four isoproteic/isolipidic plant protein-based diets were formulated to assess the lasting effects of feed additives and low fish meal (FM) and fish oil (FO) diet formulations on gilthead sea bream growth performance. FM was included at 23% in the control diet (D1) and at 3% in the other three diets (D2, D3, D4). Added oil was either FO (D1) or a blend of vegetable oils replacing 58% (D2) and 84% (D3, D4 diets) of FO. A commercial sodium butyrate preparation (NOREL, 70-BP) was added to the D4 diet at 0.4%. Each diet was allocated to triplicate groups of juvenile fish fed to satiety over an 8-month feeding trial (May-December). All fish grew efficiently from 15. g of initial body weight to 296-320. g with an overall feed efficiency (FE) of 0.95-1.01, although fish fed D3 and D4 diets showed transient growth impairments over the course of the first four weeks of the trial. Data on biometric indexes, whole body composition, haematology and blood biochemistry revealed a strong effect of sampling time in fish sampled at mid-summer (August) and late autumn (December). In contrast, the diet effect was mostly reduced to a few blood parameters. Low inclusion levels of FM reduced plasma haemoglobin levels (D2, D3), but these effects were reversed by butyrate supplementation (D4). The same phenomena occurred for total cholesterol with the highest circulating concentration of choline and IGF-I in fish fed the D4 diet during their summer growth spurt. At the transcriptional level, gene expression profiling of liver and skeletal muscle with a PCR-array of 87 growth markers provided additional evidence for an overall well-growth condition in all of the experimental groups. Up to 73 genes were found at detectable levels in the liver tissue, but only 13 were differentially expressed. Likewise, 84 genes were actively transcribed in the skeletal muscle, but only nine were differentially expressed in at least one experimental group. Butyrate supplementation reversed the up-regulated expression of inflammatory cytokines (TNFα) and muscle markers of cellular morphogenesis and protein breakdown (CDH15, CAPN3, PSMA5, PSMB1, UBE2N) in the muscle of fish fed the extreme D3 diet. These results support the use of low FM/FO diets alone or supplemented with feed additives, which have the potential to improve or reverse metabolic steady-states. Statement of relevance: Butyrate effect on low fish meal/fish oil diets. ; This study was funded by the European Union (ARRAINA, FP7-KBBE-2011-5-288925, Advanced research initiatives for nutrition and aquaculture) projects. Additional funding was obtained from the Spanish MINECO (MI2-Fish, AGL2013-48560) and from Generalitat Valenciana (PROMETEO FASE II-2014/085). ; Peer Reviewed