Patrimonialización de la alimentación, producción de un pueblo: la antigüedad como patrimonio mapuche

Este artículo busca describir y analizar el proceso de patrimonialización de la alimentación en Chile, en particular de productos y preparaciones asociados al pueblo mapuche, impulsado por el Estado. A través de observaciones en terreno y análisis de fuentes secundarias, se examinará la política patrimonial del Estado, los cambios en el pensamiento sobre el patrimonio, así como sus formatos de exhibición a lo largo de diez años. Finalmente, se propondrá que el peso del criterio de antigüedad en la selección del patrimonio se traduce en una representación de los mapuche como pueblo antiguo y origen legítimo del patrimonio nacional

Batch-Type Millimeter-Size Transformers for Miniaturized Power Applications

We have developed a novel batch-type technology for making three-dimensional (3-D) millimeter-sized transformers for ultrasmall low-power (0.1 to 1 Watt) applications. The technology uses the 3-D micropatterning of ferrite wafers by powder blasting to form the magnetic cores of the inductive devices, and combines these cores with electrical windings made by flex-foil printed circuit board technology. Microfabrication and assembly of the parts can be done in a batch process on a wafer/foil level, opening the way to further size reduction of the components. We have measured the inductive and resistive properties of our devices as a function of frequency and device geometry. The results clearly show the high potential of our technology for power applications in which small-size is important

Découpage de l'espace en unités pédopaysagères.

Il s'agit d'un modèle pour rendre compte de l'organisation des sols et des contraintes du milieu rural en mutation

Epitaxial growth and structural characterization of Pb(Fe1/2Nb1/2)O3 thin films

We have grown lead iron niobate thin films with composition Pb(Fe1/2Nb1/2)O3 (PFN) on (0 0 1) SrTiO3 substrates by pulsed laser deposition. The influence of the deposition conditions on the phase purity was studied. Due to similar thermodynamic stability spaces, a pyrochlore phase often coexists with the PFN perovskite phase. By optimizing the kinetic parameters, we succeeded in identifying a deposition window which resulted in epitaxial perovskite-phase PFN thin films with no identifiable trace of impurity phases appearing in the X-ray diffractograms. PFN films having thicknesses between 20 and 200 nm were smooth and epitaxially oriented with the substrate and as demonstrated by RHEED streaks which were aligned with the substrate axes. X-ray diffraction showed that the films were completely c-axis oriented and of excellent crystalline quality with low mosaicity (X-ray rocking curve FWHM<0.09). The surface roughness of thin films was also investigated by atomic force microscopy. The root-mean-square roughness varies between 0.9 nm for 50-nm-thick films to 16 nm for 100-nm-thick films. We also observe a correlation between grain size, surface roughness and film thickness.Comment: 13 Pages, 6 figures. To be published in J. Mag. Mag Mater. proceedings of EMRS200

Evaluación de dos fechas de siembra de Hibiscus cannabinus L. 'kenaf' (Malvaceae) en Villa del Totoral, Córdoba, Argentina

31-42El objetivo de este trabajo fue evaluar el rendimiento de fibra del cultivo de 'kenaf'en dos fechas de siembra en Villa del Totoral, Córdoba, Argentina. Se analizaron: altura de planta durante el ciclo del cultivo; diámetro basal y medio del tallo y altura a cosecha; rendimiento de fibra y contenido e índice de corteza. Se observó interacción altamente significativa entre año y fecha de siembra. En el primer año, las plantas de la siembra temprana presentaron mayores valores de altura, diámetro basal y medio y rendimiento, que las de la siembra tardía. Por el contrario en el segundo año, sólo se encontraron diferencias significativas entre fechas de siembra para ambos diámetros. El rendimiento correlacionó con altura, diámetros e índice de corteza y no con el contenido de corteza. Se sostiene que para obtener alto rendimiento de fibra de 'kenaf' en las condiciones ambientales del ensayo, es conveniente la siembra al inicio de la temporada de lluvias sin embargo, dependiendo de las condiciones ambientales, se puede esperar hasta fines de noviembre sin detrimento en los rendimientos

Synthesis and characterization of metal (M=Al or Ga) 2-phosphino (phenolate/benzenethiolate) complexes and their electrochemical behavior in the presence of CO2

A series of Group 13 complexes MLX2 (M = Al or Ga, L = SC6H4-2-PtBu2 or OC6H4-2-PtBu2, X = Me or C6F5) have been synthesized and characterized by multinuclear NMR spectroscopy and single crystal X-ray diffraction. Reactions of Me3Al or Me3Ga with an equivalent of either 2-tBu2P(C6H4)OH (1) or 2-tBu2P(C6H4)SH (5) resulted in the formation of four new (2,3,6, and 7), 4-coordinate dimethyl chelate (S,P or O,P) complexes via methane elimination. The dimethyl gallium complexes (3 and 7) underwent a further reaction with excess B(C6F5)3, and through ligand exchange (methyl/pentafluorophenyl), resulted in the disubstituted bis(pentafluorophenyl) analogs (4 and 8). Cyclic voltammetry (CV) experiments for all compounds in the presence of and the absence of (1–8) CO2 were performed. For compounds showing cathodic reduction waves under CO2 (2,3,4, and 6), bulk electrolysis experiments were performed. Electrochemical studies indicate that, for several compounds, a transient CO2 adduct is formed which undergoes a one-electron, irreversible (or partially irreversible) reduction to form an unstable radical anion

The power of monitoring: optimizing survey designs to detect occupancy changes in a rare amphibian population

Biodiversity conservation requires reliable species assessments and rigorously designed surveys. However, determining the survey effort required to reliably detect population change can be challenging for rare, cryptic and elusive species. We used a tropical bromeliad-dwelling frog as a model system to explore a cost-effective sampling design that optimizes the chances of detecting a population decline. Relatively few sampling visits were needed to estimate occupancy and detectability with good precision, and to detect a 30% change in occupancy with 80% power. Detectability was influenced by observer expertise, which therefore also had an effect on the sampling design – less experienced observers require more sampling visits to detect the species. Even when the sampling design provides precise parameter estimates, only moderate to large changes in occupancy will be detected with reliable power. Detecting a population change of 15% or less requires a large number of sites to be surveyed, which might be unachievable for range-restricted species occurring at relatively few sites. Unless there is high initial occupancy, rare and cryptic species will be particularly challenging when it comes to detecting small population changes. This may be a particular issue for long-term monitoring of amphibians which often display low detectability and wide natural fluctuations