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Alginates are renewable materials with excellent biocompatibility and cost-effectiveness in comparison with other biodegradable polymers. However, these hydrogels have poor mechanical properties that restrict their applications in biomedical fields such as skin tissue engineering. In this regard, the study follows an enhanced engineering route to produce alginate-based films reinforced with different amounts (0, 0.1, 0.5, 1 and 2% w / w) of carbon nanofibers (CNFs) and characterize their physical and biological properties. The results of this study showed that these composites possess similar biological properties to neat alginate hydrogels. Thus, none of the synthesized composite materials were cytotoxic and no cell adhesion was observed on the films. Water sorption at the body temperature did not suffer strong changes with the incorporation of CNFs into the alginate matrix. The dynamic mechanical and tensile/compressive properties of calcium alginate significantly improved with the addition of even a very low amount of CNFs. Thus, the tensile and compression modulus of the calcium alginate films in the dry and hydrated state increases up to three and six times, respectively, with the addition of 2% w / w CNFs. In addition, the composites reinforced with the lowest CNFs content have the advantage of possessing more transparency and lower production costs. Unlabelled Image • Reinforced alginate-based composites for biomedical applications • Enhancement of dynamic mechanical and tensile/compressive performance • Nanocomposites with similar biological behavior than neat alginate hydrogels • Non-cytotoxic nanocomposites in human keratinocyte HaCaT cells [ABSTRACT FROM AUTHOR]

Highly porous poly(methyl methacrylate) (PMMA) with porosities ranging from 65 to 78% were synthesised at room temperature under UV light by the polymerisation in solution method with several cross-linker contents using ethylenglycol dimethacrylate. Bulk poly(methyl methacrylate) samples (non-porous) with the same cross-linker contents were also prepared as reference materials. The results of performing thermo-mechanical analysis, differential scanning calorimetry and water sorption isotherms showed that the mechanical performance and water sorption of highly porous PMMA depends on more on the microstructure (porosity) than on the material composition only in the glassy state. Furthermore, in this broad range of temperatures, the mechanical behaviour of highly porous PMMA, considered as a biphasic material composed of bulk PMMA and pores, can be perfectly predicted by Takayanagi's three-block model. For high water activities, surprisingly, water sorption decreased considerably in highly porous PMMA as compared with bulk PMMA due to the formation of water clusters. [ABSTRACT FROM AUTHOR]

The term "Fuenteovejuna" has been used by the media of Spain and Latin America to apply to events of very different natures that in some cases share little in common with Spanish Golden Age Lope de Vega's Fuente Ovejuna. Although most news publications highlight the raising of a group of people against a situation that they consider unfair, only a few news stories portray a violent situation of self-defense against the atrocities and barbarities of an unjust ruler, as is the case in Lope's work. This paper will study the way in which the comedy Fuente Ovejuna has been read by literary critics and used by the press, to study the image that the media offers of society. The analysis of approximately one hundred news stories will show that the issue of violence and self-defense is currently only present in those that take place in Latin America, where the word "Fuenteovejuna" is generally met with negative associations. In contrast, the research will demonstrate that Spanish media often uses the word "Fuenteovejuna" positively and uses it to refer to the nonviolent demonstrations of a multitude in political and social news, which often takes place in Spain. [ABSTRACT FROM AUTHOR]

Alginate-based materials hold great promise in bioengineering applications such as skin wound healing and scaffolds for tissue engineering. Nevertheless, cell adhesion of mammalian cells on these hydrophilic materials is very poor. In cases such as polycaprolactone, poly(hydroxy-3-butyrate-co-3-valerate) and gelatin, the incorporation of hydrophobic carbon nanofibers (CNFs) and hydrophilic graphene oxide (GO) has shown significant improvement of cell adhesion and proliferation. The incorporation of these carbon nanomaterials (CNMs) into alginate films can enhance their mechanical performance, wettability, water diffusion and antibacterial properties. Herein, we report the effect of adding these CNMs into alginate films on cell adhesion for the first time. Thus, the results of this study showed that these nanocomposites are non-cytotoxic in human keratinocyte HaCaT cells. Nevertheless, contrary to what has been reported for other polymers, cell adhesion on these advanced alginate-based composites was not improved. Therefore, both types of composite films possess similar biological behavior, in terms of cell adhesion and non-cytotoxicity, and enhanced physical and antibacterial properties in comparison to neat alginate for potential biomedical and bioengineering applications. [ABSTRACT FROM AUTHOR]

A series of alginate films was synthesised with several calcium chloride cross-linker contents (from 3 to 18% w/w) with and without a very low amount (0.1% w/w) of carbon nanofibers (CNFs) in order to reduce the production costs as much as possible. The results of this study showed a very significant enhancement of liquid water diffusion and mechanical compressive modulus for high calcium chloride contents when this minuscule amount of CNFs is incorporated into calcium alginate hydrogels. These excellent results are attributed to a double cross-linking process, in which calcium cations are capable of cross-linking both alginate chains and CNFs creating a reinforced structure exhibiting ultrafast water diffusion through carbon nanochannels. Thus, these excellent results render these new alginate composites very promising for many bioengineering fields in need of low-cost advanced hydrogels with superior water diffusion and compression properties. [ABSTRACT FROM AUTHOR]