Wetting Transitions Displayed by Persistent Active Particles

A lattice model for active matter is studied numerically, showing that it displays wettings transitions between three distinctive phases when in contact with an impenetrable wall. The particles in the model move persistently, tumbling with a small rate $\alpha$, and interact via exclusion volume only. When increasing the tumbling rates $\alpha$, the system transits from total wetting to partial wetting and unwetting phases. In the first phase, a wetting film covers the wall, with increasing heights when $\alpha$ is reduced. The second phase is characterized by wetting droplets on the wall with a periodic spacing between them. Finally, the wall dries with few particles in contact with it. These phases present nonequilibrium transitions. The first transition, from partial to total wetting, is continuous and the fraction of dry sites vanishes continuously when decreasing the tumbling rate $\alpha$. For the second transition, from partial wetting to dry, the mean droplet distance diverges logarithmically when approaching the critical tumbling rate, with saturation due to finite-size effects

Preferencias del consumidor hacia la carne bovina en Chile : Importancia del país de origen, corte, envasado, marca y precio

A study was carried out to evaluate preferences for two cuts, four countries of origin, two forms of presentation, brand and different prices of beef cattle among supermarket buyers in southern Chile, and to distinguish the existence of different market segments, through a survey of 800 people. Using a fractional factorial design for conjoint analysis, it was determined overall that the origin was more important (44.5%) than price (20.8%), form of presentation (12.2%), cut (12.0%) and brand (10.5%), with preference for Chilean and Argentinean striploin, packaged on trays, with no brand at medium price. Using a cluster analysis, three market segments were distinguished. The largest (52.3%) placed great importance on origin and preferred the highest price. The second (27.5%) also valued origin with the greatest preference for Argentinean beef, and it was the only group that preferred the ribeye as the cut. The third (20.5%) placed the greatest importance on price, and was the only group that preferred Paraguayan meat. The segments differed in the importance of eating meat for their personal well-being. The low importance of packaging and brand indicates poorly developed marketing of this product. In order to properly insert brand beef in the Chilean market, communication strategies must be implemented that identify the product with superior quality and that position the brand in the consumer's mind.Se evaluaron las preferencias hacia dos cortes, cuatro países de origen, dos formas de presentación, marca y distintos precios de carne bovina en compradores de supermercados del sur de Chile, y la existencia de diferentes segmentos de mercado, mediante una encuesta a 800 personas. Mediante análisis conjunto de diseño factorial fraccionado se determinó, en general, que el origen fue más importante (44,5%), que el precio (20,8%), la forma de presentación (12,2%), corte (12,0%) y marca (10,5%), con preferencia por el lomo liso chileno y argentino, envasado en bandejas, sin marca a un precio medio. Mediante análisis cluster se distinguieron tres segmentos de mercado. El mayoritario (52,3%) dio alta importancia al origen y prefirió el precio mayor. El segundo (27,5%) también valoró el origen con la mayor preferencia por la carne argentina y fue el único que prefirió el lomo vetado al corte. El tercero (20,5%) dio mayor importancia al precio, siendo el único que prefirió la carne paraguaya. Los segmentos difirieron en la importancia asignada al consumo de carne para su bienestar personal. La baja importancia del envase y de la marca indica un bajo desarrollo comercial en este producto. Para lograr una adecuada penetración de carne bovina con nombre de marca en el mercado chileno, se deben implementar estrategias comunicacionales que identifiquen el producto con una calidad superior y que posicionen la marca en la mente del consumidor.Fil: Schnettler, Berta. Universidad de La Frontera (Chile). Facultad de Ciencias Agropecuarias y Forestales. Departamento de Producción Agropecuaria.Fil: Sepúlveda, Néstor. Universidad de La Frontera (Chile). Facultad de Ciencias Agropecuarias y Forestales. Departamento de Producción Agropecuaria.Fil: Sepúlveda, José. Chile. Universidad de La Frontera. Centro de Psicología Económica y del Consumo.Fil: Orellana, Ligia. Chile. Universidad de La Frontera. Centro de Psicología Económica y del Consumo.Fil: Miranda, Horacio. Universidad de La Frontera (Chile). Facultad de Ciencias Agropecuarias y Forestales. Departamento de Producción Agropecuaria.Fil: Lobos, Germán. Universidad de TalcaFil: Mora, Marcos. Universidad de Chile. Facultad de Ciencias Agronómicas. Departamento de Economía Agraria

Preferencias del consumidor hacia la carne bovina en Chile: Importancia del país de origen, corte, envasado, marca y precio

A study was carried out to evaluate preferences for two cuts, four countries of origin, two forms of presentation, brand and different prices of beef cattle among supermarket buyers in southern Chile, and to distinguish the existence of different market segments, through a survey of 800 people. Using a fractional factorial design for conjoint analysis, it was determined overall that the origin was more important (44.5%) than price (20.8%), form of presentation (12.2%), cut (12.0%) and brand (10.5%), with preference for Chilean and Argentinean striploin, packaged on trays, with no brand at medium price. Using a cluster analysis, three market segments were distinguished. The largest (52.3%) placed great importance on origin and preferred the highest price. The second (27.5%) also valued origin with the greatest preference for Argentinean beef, and it was the only group that preferred the ribeye as the cut. The third (20.5%) placed the greatest importance on price, and was the only group that preferred Paraguayan meat. The segments differed in the importance of eating meat for their personal well-being. The low importance of packaging and brand indicates poorly developed marketing of this product. In order to properly insert brand beef in the Chilean market, communication strategies must be implemented that identify the product with superior quality and that position the brand in the consumer's mind.Se evaluaron las preferencias hacia dos cortes, cuatro países de origen, dos formas de presentación, marca y distintos precios de carne bovina en compradores de supermercados del sur de Chile, y la existencia de diferentes segmentos de mercado, mediante una encuesta a 800 personas. Mediante análisis conjunto de diseño factorial fraccionado se determinó, en general, que el origen fue más importante (44,5%), que el precio (20,8%), la forma de presentación (12,2%), corte (12,0%) y marca (10,5%), con preferencia por el lomo liso chileno y argentino, envasado en bandejas, sin marca a un precio medio. Mediante análisis cluster se distinguieron tres segmentos de mercado. El mayoritario (52,3%) dio alta importancia al origen y prefirió el precio mayor. El segundo (27,5%) también valoró el origen con la mayor preferencia por la carne argentina y fue el único que prefirió el lomo vetado al corte. El tercero (20,5%) dio mayor importancia al precio, siendo el único que prefirió la carne paraguaya. Los segmentos difirieron en la importancia asignada al consumo de carne para su bienestar personal. La baja importancia del envase y de la marca indica un bajo desarrollo comercial en este producto. Para lograr una adecuada penetración de carne bovina con nombre de marca en el mercado chileno, se deben implementar estrategias comunicacionales que identifiquen el producto con una calidad superior y que posicionen la marca en la mente del consumidor

Evolutionary Plasticity of Habenular Asymmetry with a Conserved Efferent Connectivity Pattern

The vertebrate habenulae (Hb) is an evolutionary conserved dorsal diencephalic nuclear complex that relays information from limbic and striatal forebrain regions to the ventral midbrain. One key feature of this bilateral nucleus is the presence of left-right differences in size, cytoarchitecture, connectivity, neurochemistry and/or gene expression. In teleosts, habenular asymmetry has been associated with preferential innervation of left-right habenular efferents into dorso-ventral domains of the midbrain interpeduncular nucleus (IPN). However, the degree of conservation of this trait and its relation to the structural asymmetries of the Hb are currently unknown. To address these questions, we performed the first systematic comparative analysis of structural and connectional asymmetries of the Hb in teleosts. We found striking inter-species variability in the overall shape and cytoarchitecture of the Hb, and in the frequency, strength and to a lesser degree, laterality of habenular volume at the population level. Directional asymmetry of the Hb was either to the left in D. rerio, E. bicolor, O. latipes, P. reticulata, B. splendens, or to the right in F. gardneri females. In contrast, asymmetry was absent in P. scalare and F. gardneri males at the population level, although in these species the Hb displayed volumetric asymmetries at the individual level. Inter-species variability was more pronounced across orders than within a single order, and coexisted with an overall conserved laterotopic representation of left-right habenular efferents into dorso-ventral domains of the IPN. These results suggest that the circuit design involving the Hb of teleosts promotes structural flexibility depending on developmental, cognitive and/or behavioural pressures, without affecting the main midbrain connectivity output, thus unveiling a key conserved role of this connectivity trait in the function of the circuit. We propose that ontogenic plasticity in habenular morphogenesis underlies the observed inter-species variations in habenular asymmetric morphology

Fatty acid composition (MUFA and CLA) related with the G.878TC SCD gene polymor phism in abeerdeen angus steers

The composition of the fatty acids (FA) in meat is of great importance in the human diet. There are polyunsaturated and monounsaturated fatty acids (MUFA and PUFA) whose intake is reported as beneficial for a healthy diet. In addition, beef is of great importance as a functional food because it is an important source of conjugated linoleic acid (CLA), which has a key role in human health.Fil: Inostroza, Karla. Universidad de La Frontera (Chile)Fil: Larama, Giovanni . Universidad de La Frontera (Chile)Fil: Bravo, Silvana. Universidad de La Frontera (Chile)Fil: Sepúlveda, Néstor. Universidad de La Frontera (Chile

Methane dry reforming over Ni supported on pine sawdust activated carbon: Effects of support surface properties and metal loading

The influence of metal loading and support surface functional groups (SFG) on methane dry reforming (MDR) over Ni catalysts supported on pine-sawdust derived activated carbon were studied. Using pine sawdust as the catalyst support precursor, the smallest variety and lowest concentration of SFG led to best Ni dispersion and highest catalytic activity, which increased with Ni loading up to 3 Ni atoms nm-2. At higher Ni loading, the formation of large metal aggregates was observed, consistent with a lower "apparen" surface area and a decrease in catalytic activity. The H2/CO ratio rose with increasing reaction temperature, indicating that increasingly important side reactions were taking place in addition to MDR.Financial support was provided by CONICYT PFB-27 project (UDT-University of Concepción) and FONDECYT 1100884 grant

Efecto de la suplementación con aceite de canola sobre la expresión del gem SCD y el perfil lipídico de la carne de cordero

SCD es el gen clave de la síntesis de ácidos grasos monoinsaturados (MUFA) de la carne de cordero, ya que codifica para una enzima del mismo nombre que mediante los ácidos grasos C16:0 y C18:0 produce C16:1 y C18:1, respectivamente. No obstante, el porcentaje de MUFA de la carne de cordero es baja en comparación con los ácidos grasos saturados (SFA), que posiblemente son perjudiciales para la salud humana.Fil: Quiñones, John. Universidad de La Frontera (Chile)Fil: Díaz, Rommy. Universidad de La Frontera (Chile)Fil: Cancino, David. Universidad de La Frontera (Chile)Fil: Farías, Jorge. Universidad de La Frontera (Chile)Fil: Sepúlveda, Néstor. Universidad de La Frontera (Chile

Efectos del almacenamiento en frío y la crippreservación sobre los lípidos y la ultraestructura del espermatozoide de salmón del atlántico

Chile es el segundo productor mundial de Salmón del atlántico (Salmo salar). Una de las tecnologías más importantes en la cadena productiva del salmón corresponde al resguardo de la fertilidad de reproductores de alto valor. Las herramientas que existen para preservar este tipo de gametos consisten en almacenarlos en frio (4°C) o criopreservarlos (-196°C). La membrana de los espermatozoides está constituida por una serie de lípidos que son muy importantes para mantener su integridad y funcionalidad en los procesos de fertilización.Fil: Farías, José. Universidad de La Frontera (Chile).Fil: Díaz, Rommy . Universidad de La Frontera (Chile).Fil: Quiñones, John. Universidad de La Frontera (Chile).Fil: Cancino, David. Universidad de La Frontera (Chile).Fil: Sepúlveda, Néstor. Universidad de La Frontera (Chile)

Carbon nanotube-supported Ni–CeO2 catalysts. Effect of the support on the catalytic performance in the low-temperature WGS reaction

The low temperature water-gas shift (WGS) reaction has been studied over two commercial multiwall carbon nanotubes-supported nickel catalysts promoted by ceria. For comparison purposes, activated carbon-supported catalysts have also been studied. The catalytic performance and the characterization by N2 adsorption analysis, powder X-ray diffraction (XRD), temperature-programmed reduction with H2 (TPR-H2), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) analysis showed that the surface chemistry has an important effect on the dispersion of ceria. As a result, ceria was successfully dispersed over the carbon nanotubes (CNTs) with less graphitic character, and the catalyst afforded better activity in WGS than the catalyst prepared over massive ceria. Moreover, a 20 wt.% CeO2 loading over this support was more active than the analogous catalyst with a 40 wt.% loading. The ceria nanoparticles were smaller when the support was previously oxidized, however this resulted in a decrease of the activity.Financial support from CONICYT (Chile, Postdoc FONDECYT 3130483), Ministerio de Economía y Competitividad (Spain, MAT2010-21147 and MAT2013-45008-P) and Generalitat Valenciana (Spain, PROMETEOII/2014/004) is gratefully acknowledged