2,118 research outputs found
Respuestas de los consumidores a los hoteles certificados medioambientalmente: el efecto moderador de la conciencia medioambiental sobre la formación de intenciones comportamentales
Este estudio desarrolla un modelo que explora la relación entre las prácticas verdes, la imagen verde, la conciencia medioambiental y las intenciones comportamentales de los clientes en un contexto hotelero certificado. Para testar empíricamente el modelo propuesto se realizaron 502 encuestas personales a clientes hoteleros en España. Los resultados muestran como las percepciones de los clientes sobre las prácticas verdes tienen un efecto directo y positivo en la imagen verde de las compañías hoteleras. Al mismo tiempo, esta imagen influye directa y positivamente sobre las intenciones de comportamiento de los clientes hacia los hoteles certificados medioambientalmente. También se demuestra que cuanto mayor sea la conciencia medioambiental de los consumidores, mayor será su intención de hospedarse, realizar comentarios positivos y pagar una prima por alojarse en hoteles certificados. Por último, la conciencia medioambiental ejerce un efecto moderador sobre la relación causal entre la imagen verde y las intenciones comportamentales.This study develops a model that investigates the relationship among green practices, green image, environmental consciousness and the behavioral intentions of customers in a certified hotel context. The study examines the direct and the moderating role of environmental consciousness in the formation of behavioral intentions based on green initiatives. To test the proposed model empirically, 502 personal surveys of hotel customers were conducted in Spain. The findings show that customer perceptions of green practices have a positive direct effect on a hotel´s green image. At the same time, this environmental image has positive direct effects on customer behavioral intentions towards certified hotels. The authors also found that the higher the environmental consciousness of consumers, the greater their intention to stay, to spread positive word-of-mouth and pay a premium for environmentally-certified hotels. Finally, consumer environmental consciousness also exerts a moderating effect on the causal relationship between green image and behavioral intentions
Analysis of the rear leg rotation movement during the fencing lunge
The most relevant aulhois of fencing agree on the extension of the rear leg's knee from the on guard position, which is the ona thai provides ihe real speed to the lunge, and the extension of the arm only serves to drive the points towards the target. All the authors coincide thai it is important to keep the whole sole of the rear Foot supported on the Boor, keeping the same direction and without sliding it during the movernent, being the only one support that assures a really fast and balanced lunge, allowing the return to the on guard position or to continue towards ahead. Nevertheless, in a competition it may be observed that there are just a few fencers that keep the position of the feet in 90° angle during the lunge, as proposed in the fencing books. From this situation, we try to know if the rotation movement of the rear leg improve the speed of the Mass Centre and the weapon
Topografía inducida en recubrimientos a partir de híbridos y compuestos sílice/polímero: superhidrofobia, transparencia y estabilidad mecánica
Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física Aplicada. Fecha de lectura. Fecha de lectura: 28-10-201
Control biológico de cría yesificada
La cría yesificada es una micosis invasiva ocasionada por el hongo heterotálico Ascosphaera apis que afecta exclusivamente a las larvas de las abejas. La enfermedad tiene difusión mundial y en la Argentina se halla diseminada en todas las áreas donde se realiza apicultura. Se estudió la potencialidad de 249 cepas de bacterias esporuladas aeróbicas aisladas de miel como agentes biocontroladores del hongo mediante un ensayo en disco central en condiciones de laboratorio. Se seleccionaron como mejores antagonistas 10 cepas bacterianas las que se evaluaron contra 10 aislamientos de A. apis. Un ANOVA y posterior comparación de medias por LSD mostró a las cepas B. subtilis (m329), B. megaterium (m435) y B. circulans Fr 231 y m448b como las más eficaces en controlar el desarrollo del hongo
Medium-frequency electrical resistance sintering of oxidized C.P. iron powder
Commercially pure (C.P.) iron powders with a deliberate high degree of oxidation were consolidated by medium-frequency electrical resistance sintering (MF-ERS). This is a consolidation technique where pressure, and heat coming from a low-voltage and high-intensity electrical current, are simultaneously applied to a powder mass. In this work, the achieved densification rate is interpreted according to a qualitative microscopic model, based on the compacts global porosity and electrical resistance evolution. The effect of current intensity and sintering time on compacts was studied on the basis of micrographs revealing the porosity distribution inside the sintered compact. The microstructural characteristics of compacts consolidated by the traditional cold-press and furnace-sinter powder metallurgy route are compared with results of MF-ERS consolidation. The goodness of MF-ERS versus the problems of conventional sintering when working with oxidized powders is analyzed. The electrical consolidation can obtain higher densifications than the traditional route under non-reducing atmospheres.Ministerio de Economía y Competitividad DPI2015-69550-C2-1-PMinisterio de Economía y Competitividad DPI2015-69550-C2-2-
Perceived Video Quality Estimation from Spatial and Temporal Information Contents and Network Performance Parameters in IPTV
The paper proposes a model for estimation of perceived video quality in IPTV, taking as input both video coding and network Quality of Service parameters. It includes some fitting parameters that depend mainly on the information contents of the video sequences. A method to derive them from the Spatial and Temporal Information contents of the sequences is proposed. The model may be used for near real-time monitoring of IPTV video quality
Spray Pyrolysis Processing for Optoelectronic Applications
Spray pyrolysis is a low-cost and simple technique for the fabrication of high-quality transparent and conducting oxide thin films for different optoelectronic applications. The fabrication method, structural, morphological, and electro-optical properties of fluorine-doped tin oxide (FTO) and tin-doped indium oxide (ITO) films have been investigated. The deposited films have low resistivity and high transparency. Applications of such films are shown in high-efficiency surface-barrier photodetectors and solar cells, where the films serve as an active and antireflection electrode. A short description of other undoped and doped oxide films such as ZnO and TiO2 fabricated by spray pyrolysis is presented
Fracture toughness of cemented carbides obtained by electrical resistance sintering
The unique combination of hardness, toughness and wear resistance exhibited by WC-Co cemented carbides (hardmetals) has made them a preeminent material choice for extremely demanding applications, such as metal cutting/forming tools or mining bits, in which improved and consistent performance together with high reliability are required. The high fracture toughness values exhibited by hardmetals are mainly due to ductile ligament bridging and crack deflection (intrinsic to carbides). In this work two WC-Co grades obtained by using the electric resistance sintering technique are studied. The relationships between the process parameters (cobalt volume fraction, sintering current and time, die materials, etc.), the microstructural characteristics (porosity, cobalt volume fraction, carbide grain size, binder thickness and carbide contiguity) and mechanical properties (Vickers hardness and fracture toughness) are established and discussed. Also the presence of microstructural anisotropy and residual stresses is studied. The sintering process at 7 kA, 600 ms and 100 MPa, in an alumina die, followed by a treatment of residual stress relief (800 °C, 2 h in high vacuum), allows to obtain WC-Co pellets with the best balance between an homogeneous microstructure and mechanical behaviour.EU for funding this research with in the framework of the EU 7th Framework FoF.NMP.2013-10 608729 EFFIPRO Projec
SYSTEMIC ADMINISTRATION OF EPOTHYLONE-D RECUES MEMORY AND AMELIORATES ALZHEIMER’S DISEASE-LIKE PATHOLOGY IN APP/PS1 MICE
Aims
Cognitive and memory decline in Alzheimer's disease (AD) patients is highly related to synaptic dysfunction and neuronal loss. Tau hyperphosphorylation destabilizes microtubules leading to axonal transport failure, accumulation of autophagy/vesicular material and the generation of dystrophic neurites, thus contributing to axonal/synaptic dysfunction. In this study, we analyzed the effect of a microtubule-stabilizing drug in the progression of the disease in an APP751SL/PS1M146L transgenic model.
Method
APP/PS1 mice (3 month-old) were weekly treated with 2 mg/kg intraperitoneal injections of Epothilone-D (Epo-D) for 3 months. Vehicle-injected animals were used as controls. For memory performance, animals were tested on the object-recognition tasks, Y-maze and Morris water maze. Levels of Abeta, ubiquitin, AT8 and synaptic markers were analyzed by Western-blot. Hippocampal plaque burden, dystrophic and synaptic loadings were quantified after immunostaining by image analysis.
Results
Epo-D treated mice showed a significant improvement in the performance of hippocampus-associated cognitive tests compared to controls. This memory recovery correlated with a significant reduction in the AD-like hippocampal pathology. Abeta, APP and ubiquitin levels were significantly reduced in treated animals, and a decrease in both the plaque loading and the axonal pathology was also found. Finally, synaptic levels were significantly preserved in treated animals in comparison with controls.
Conclusion
Epo-D treatment promotes synaptic and cognitive improvement, reduces the accumulation of extracellular Abeta and the associated neuritic pathology in the hippocampus of APP/PS1 model. Therefore, microtubule stabilizing drugs could be considered therapeutical candidates to slow down AD progression.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Supported by FIS-PI15/00796 (AG), FIS-PI15/00957(JV) and co-financed by FEDER funds from European Union
Epothilone-d rescues cognition and attenuates alzheimer’s disease-like pathology in APP/PS1 mice
AIMS: Cognitive decline in Alzheimer's disease (AD) patients has been linked to synaptic damage and neuronal loss. Hyperphosphorylation of tau protein destabilizes microtubules leading to the accumulation of autophagy/vesicular material and the generation of dystrophic neurites, thus contributing to axonal/synaptic dysfunction. In this study, we analyzed the effect of a microtubule-stabilizing compound in the progression of the disease in the hippocampus of APP751SL/PS1M146L transgenic model.
METHODS: APP/PS1 mice (3 month-old) were treated with a weekly intraperitoneal injection of 2 mg/kg epothilone-D (Epo-D) for 3 months. Vehicle-injected animals were used as controls. Mice were tested on the Morris water maze, Y-maze and object-recognition tasks for memory performance. Abeta, AT8, ubiquitin and synaptic markers levels were analyzed by Western-blots. Hippocampal plaque, synaptic and dystrophic loadings were quantified by image analysis after immunohistochemical stainings.
RESULTS: Epo-D treated mice exhibited a significant improvement in the memory tests compared to controls. The rescue of cognitive deficits was associated to a significant reduction in the AD-like hippocampal pathology. Levels of Abeta, APP and ubiquitin were significantly reduced in treated animals. This was paralleled by a decrease in the amyloid burden, and more importantly, in the plaque-associated axonal dystrophy pathology. Finally, synaptic levels were significantly restored in treated animals compared to controls.
CONCLUSION: Epo-D treatment promotes synaptic and spatial memory recovery, reduces the accumulation of extracellular Abeta and the associated neuritic pathology in the hippocampus of APP/PS1 model. Therefore, microtubule stabilizing drugs could be considered therapeutical candidates to slow down AD progression.
Supported by FIS-PI12/01431 and PI15/00796 (AG),FIS-PI12/01439 and PI15/00957(JV)Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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