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A functional comparison of three human SAPKs with fungal Hog1p was undertaken, using Saccharomyces cerevisiae as a heterologous expression system. We characterized the role of mammalian MAP kinases in sensitivity to both osmotic and oxidative stress of a S. cerevisiae hog1 mutant. Western blot analyses indicated that S. cerevisiae can only phosphorylate mammalian MAP kinases in response to osmotic stress but not to oxidative stress, while morphogenetic defects characteristic of hog1 mutants under hyperosmotic stress are only suppressed by fungal and not mammalian Hog1p. Our data demonstrate the functional conservation of MAPKs although they also evidence differential aspects among the three human SAPKs and the fungal MAPKs.  相似文献   
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Food lipid major components are usually analyzed by individual methodologies using diverse extractive procedures for each class. A simple and fast extractive procedure was devised for the sequential analysis of vitamin E, cholesterol, fatty acids, and total fat estimation in seafood, reducing analyses time and organic solvent consumption. Several liquid/liquid-based extractive methodologies using chlorinated and non-chlorinated organic solvents were tested. The extract obtained is used for vitamin E quantification (normal-phase HPLC with fluorescence detection), total cholesterol (normal-phase HPLC with UV detection), fatty acid profile, and total fat estimation (GC-FID), all accomplished in <40 min. The final methodology presents an adequate linearity range and sensitivity for tocopherol and cholesterol, with intra- and inter-day precisions (RSD) from 3 to 11 % for all the components. The developed methodology was applied to diverse seafood samples with positive outcomes, making it a very attractive technique for routine analyses in standard equipped laboratories in the food quality control field.  相似文献   
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This paper presents the work carried out within the European project RENAISSANCE‐ITN, which was dedicated to the development of innovative polyelectrolytes for energy and environmental applications. Within the project different types of innovative polyelectrolytes were synthesized such as poly(ionic liquid)s coming from renewable or natural ions, thiazolium cations, catechol functionalities or from a new generation of cheap deep eutectic monomers. Further, macromolecular architectures such as new poly(ionic liquid) block copolymers and new (semi)conducting polymer/polyelectrolyte complexes were also developed. As the final goal, the application of these innovative polymers in energy and the environment was investigated. Important advances in energy storage technologies included the development of new carbonaceous materials, new lignin/conducting polymer biopolymer electrodes, new iongels and single‐ion conducting polymer electrolytes for supercapacitors and batteries and new poly(ionic liquid) binders for batteries. On the other hand, the use of innovative polyelectrolytes in sustainable environmental technologies led to the development of new liquid and dry water, new materials for water cleaning technologies such as flocculants, oil absorbers, new recyclable organocatalyst platforms and new multifunctional polymer coatings with antifouling and antimicrobial properties. All in all this paper demonstrates the potential of poly(ionic liquid)s for high‐value applications in energy and enviromental areas. © 2017 Society of Chemical Industry  相似文献   
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One of the most important research topics in the area of Intelligent Manufacture Systems (IMS) is the automatic detection of tool breakage, wear of chipping during the cutting process. Sensor-based techniques are available for cutting force measurements, but there are drawbacks in this approach in cost and idle times. This work proposes a sensorless monitoring system for tool monitoring in order to detect breakage and chipping by exploiting the wavelet transform and a neural network. Previous works have made use of these tools for monitoring several machining parameters, but we propose an integrated low-cost approach to detect quickly the changes in the tool integrity for monitoring. The system output produces an accurate detection of the tool integrity that enables the system to prevent damage due to tool breakage. This approach allows for an industrial solution to be developed.  相似文献   
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In this study, a novel kind of hybrid pigment based on nanoclays and dyes was synthesized and characterized. These nanoclay‐based pigments (NCPs) were prepared at the laboratory with sodium montmorillonite nanoclay (NC) and methylene blue (MB). The cation‐exchange capacity of NC exchanged with MB was varied to obtain a wide color gamut. The synthesized nanopigments were thoroughly characterized. The NCPs were melt‐mixed with linear low‐density polyethylene (PE) with an internal mixer. Furthermore, samples with conventional colorants were prepared in the same way. Then, the properties (mechanical, thermal, and colorimetric) of the mixtures were assessed. The PE–NCP samples developed better color properties than those containing conventional colorants and used as references, and their other properties were maintained or improved, even at lower contents of dye compared to that with the conventional colorants. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
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The catalytic activity of different heterogeneous sulfonic acid-modified catalysts has been assayed in the simultaneous esterification of FFA and transesterification of triglycerides of crude palm oil (FFA content of 5.6 wt%) with methanol, demonstrating the applicability of this kind of acid solids to the one-step production of biodiesel from FFA-containing vegetable oils. The yield towards fatty acid methyl esters (FAMEs) obtained over these acid materials is enhanced when increasing the acid strength of the catalytic site. Likewise, the use of mesostructured supports has been shown as a factor improving the catalytic performance as compared with macroporous sulfonic acid-based resins, likely due to an enhancement of the mass transfer rates of large molecules, such as triglycerides, within the catalyst structure. Thus, the combination of the open mesoporous structure of a SBA-15 silica support with relatively strong arenesulfonic acid sites leads to a material able to yield high conversion of triglycerides and free fatty acids. Furthermore, a study on the transesterification reaction of crude palm oil with methanol through a surface response analysis has provided as optimal conditions the following: temperature 160 °C, catalyst loading 5.1 wt% referred to the amount of palm oil, and methanol to oil molar ratio 30. Under these conditions, almost 90% of the starting oil is converted to FAME after reacting for just 2 h of reaction. Likewise, surface response analysis has evidenced a strong interaction between temperature and methanol to oil ratio.  相似文献   
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