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A study of the peen forming of thin stainless steel metal foils (50 μm thick) using a solid-state ps-pulsed laser, emitting at a wavelength of 1064 nm was conducted. The pitch distance between consecutive laser pulses was kept constant by tuning the laser repetition rate from 0.4 to 10 kHz, and subsequently the scanning speed. The induced bending angle and the radius of curvature were used to measure the effect of the treatment. Their dependence on the pulse energy, the treated area, the distance between lines, and the laser repetition rate was studied. High repetition rates do not allow the sample to cool down, affecting the bending to the point of being negligible. An FEM simulation and experiments were carried out to prove that the increase in temperature due to high repetition rate can relax the stresses induced by laser peen treatment, thus preventing bending in the sample.

En este artículo se hace un estudio descriptivo de la experiencia espiritual que tienen los estudiantes de la Universidad Pontificia Bolivariana de Medellín, teniendo en cuenta el trasfondo teórico que ofrece el giro teológico de la fenomenología francesa y la escala para evaluar la experiencia espiritual diaria (DSES) de Lynn G. Underwood (1999); las variables que se tomaron en este estudio fueron la edad, el género, la carrera y los puntajes de la escala, teniendo en cuenta los efectos conductuales de la experiencia divina como variables de criterio. Se tomó una muestra de 317 estudiantes de 25 carreras, con edades entre los 17 y los 55 años, de los cuales 269 (85% de la muestra) tienen entre 17 y 23 años de edad. En los resultados, la discusión y las conclusiones, se presenta un análisis de la espiritualidad según los valores arrojados por la escala, leídos bajo el lente de la experiencia mística y la fenomenología de la donación. En efecto, la aproximación a Dios que ofrece la ontoteología es fija, invariable y conceptual; mientras que la mística no pretende explicar quién es Dios, sino relacionarse con él, experimentarlo y gozar de sus efectos, que ineluctablemente redundan en el amor al otro.

Laser-induced forward transfer for high-viscosity—of Pa·s—pastes differ from standard LIFT processes in its dynamics. In most techniques, the transference after setting a great gap does not modify the shape acquired by the fluid, so it stretches until it breaks into droplets. In contrast, there is no transferred material when the gap is bigger than three times the paste thickness in LIFT for high-viscosity pastes, and only a spray is observed on the acceptor using this configuration. In this work, the dynamics of the paste have been studied using a finite-element model in COMSOL Multiphysics, and the behavior of the paste varying the gap between the donor and the acceptor substrates has also been modeled. The paste bursts for great gaps, but it is confined when the acceptor is placed close enough. The obtained simulations have been compared with a previous work, in which the paste structures were photographed. The analysis of the simulations in terms of speed allows for predicting the burst of the paste—spray regime—and the construction of a printability map regarding the gap between the substrates.

The Ni-hard alloys white-cast irons are generally used for high wear work. Among them, those with better impact resistance because of its low carbon content compared to the rest of the family, are studied in this paper. One experimental technique of characterizing the metallic materials is the microstructural study. Several metallographic attacks intended to reveal qualitatively each microconstituent that forms the alloy, as well as the segregation and solidification structure of casting, are studied in this article. The use of color metallography is fundamental in this case to distinguish clearly the microconstituents. The main objective of this paper is to propose a series of attacks that identify each one of the microconstituents present in the alloy that has not been reported up to date.

The aromatic metabolites derived from yeast metabolism determine the characteristics of aroma and taste in wines, so they are considered of great industrial interest. Volatile esters represent the most important group and therefore, their presence is extremely important for the flavor profile of the wine. In this work, we use and compare two Saccharomyces cerevisiae yeast strains: P29, typical of sparkling wines resulting of second fermentation in a closed bottle; G1, a flor yeast responsible for the biological aging of Sherry wines. We aimed to analyze and compare the effect of endogenous CO2 overpressure on esters metabolism with the proteins related in these yeast strains, to understand the yeast fermentation process in sparkling wines. For this purpose, protein identification was carried out using the OFFGEL fractionator and the LTQ Orbitrap, following the detection and quantification of esters with gas chromatograph coupled to flame ionization detector (GC-FID) and stir-bar sorptive extraction, followed by thermal desorption and gas chromatography-mass spectrometry (SBSE-TD-GC-MS). Six acetate esters, fourteen ethyl esters, and five proteins involved in esters metabolism were identified. Moreover, significant correlations were established between esters and proteins. Both strains showed similar behavior. According to these results, the use of this flor yeast may be proposed for the sparkling wine production and enhance the diversity and the typicity of sparkling wine yeasts.

Epidemiological and clinical studies have reported that olive oil reduces the incidence of cardiovascular disease. However, the mechanisms involved in this beneficial effect have not been delineated. The endothelium plays an important role in blood pressure regulation through the release of potent vasodilator and vasoconstrictor agents such as nitric oxide (NO) and endothelin-1 (ET-1), respectively, events that are disrupted in type 2 diabetes. Extra virgin olive oil contains polyphenols, compounds that exert a biological action on endothelial function. This study analyzes the effects of olive oil polyphenols on endothelial dysfunction using an in vitro model that simulates the conditions of type 2 diabetes. Our findings show that high glucose and linoleic and oleic acids decrease endothelial NO synthase phosphorylation, and consequently intracellular NO levels, and increase ET-1 synthesis by ECV304 cells. These effects may be related to the stimulation of reactive oxygen species production in these experimental conditions. Hydroxytyrosol and the polyphenol extract from extra virgin olive oil partially reversed the above events. Moreover, we observed that high glucose and free fatty acids reduced NO and increased ET-1 levels induced by acetylcholine through the modulation of intracellular calcium concentrations and endothelial NO synthase phosphorylation, events also reverted by hydroxytyrosol and polyphenol extract. Thus, our results suggest a protective effect of olive oil polyphenols on endothelial dysfunction induced by hyperglycemia and free fatty acids.

Eicosanoids participate in the regulation of cellular proliferation. Thus, we observed that prostaglandin E2 interaction with membrane receptors is involved in the control of 3T6 fibroblast growth induced by serum. However, our results suggested that another arachidonic acid pathway might be implicated in these events. Our results show that 3T6 fibroblasts synthesized hydroxyeicosatetraenoic acids (HETEs) such as 12-HETE through the cytochrome P-450 (CYP450) pathway. However, 3T6 fibroblasts did not produce leukotriene B4 (LTB4), and lipoxygenase inhibitors and LT antagonists failed to inhibit 3T6 fibroblast growth induced by FBS. In contrast, we observed that CYP450 inhibitors such as SKF-525A, 17-octadecynoic acid, 1-aminobenzotriazole, and 6-(2-propargyloxyphenyl)hexanoic acid reduced 12(S)-HETE levels, 3T6 fibroblast growth, and DNA synthesis induced by FBS. The impairment of DNA synthesis and 3T6 fibroblast growth induced by SKF-525A were reversed by exogenous addition of HETEs. Moreover, we report that 5-HETE, 12(S)-HETE, and 15(S)-HETE are mitogenic on 3T6 fibroblast in the absence of another growth factor, and this effect was dependent on the activation of the phosphatidylinositol-3-kinase pathway. In conclusion, our results show that HETEs, probably produced by CYP450, are involved in the control of 3T6 fibroblast growth.

El paisaje, considerado desde la perspectiva sistémica, se concibe como un complejo territorial que puede ser sometido a análisis siguiendo distintas fórmulas de aproximación al mismo. A pesar de las diferencias que se observan entre estos modelos de acercamiento, todos ellos se fundamentan en el análisis integrado de los componentes del paisaje y de sus mutuas relaciones. Las técnicas de integración conducentes a la obtención de unidades sistémicas de paisaje y a la delimitación espacial de las mismas encuentran un aliado excepcional en los SIG. Tanto en el procedimiento de «superposición» como en el de «combinación cartográfica» el empleo de los Sistemas de Información Geográfica representa un avance sustantivo en la instrumentalización del método. En esta comunicación pretendemos concretar el uso de esta herramienta de análisis espacial para cada una de las fases que componen la secuencia metodológica de identificación y cartografía de geosistemas o geocomplejos y, para ello, presentaremos su aplicación a la cuenca vertiente del río Guadix.