Gowdy T3T^3 Cosmological Models in N=1 Supergravity

We investigate the canonical quantization of supergravity N=1 in the case of a midisuperspace described by Gowdy $T^3$ cosmological models. The quantum constraints are analyzed and the wave function of the universe is derived explicitly. Unlike the minisuperspace case, we show the existence of physical states in midisuperspace models. The analysis of the wave function of the universe leads to the conclusion that the classical curvature singularity present in the evolution of Gowdy models is removed at the quantum level due to the presence of the Rarita-Schwinger field.Comment: 25 pages and 2 figure

"Behind the Ecce Homo," Rural Development Policy and the Effects of Depopulation on the Preservation of Spanish Heritage

The ongoing process of rural depopulation that Europe has experienced during the 20th century has had a considerably negative effect on the conservation of vernacular and historic buildings located in rural areas. Although this is a continental phenomenon, it seems to be especially prevalent in Southern Europe, and particularly in Spain. Taking the infamous restoration of the "Ecce Homo" fresco in the town of Borja (Zaragoza) as a starting point, this thesis aims to examine this problem, explore its magnitude, and identify challenges and opportunities to incorporate historic preservation into existing policies for rural development. The primary aim of this thesis is to build more knowledge and understanding about this issue, which has been the focus of very limited scholarly research. Therefore, this thesis includes a detailed description of depopulation and rural heritage in the European and Spanish context, based on an extensive literature review and supplemented by the study of a particular Spanish rural area, the "comarcas" of Daroca, Jiloca, and Molina. In addition, a thorough policy review is presented, analyzing the extent to which historic preservation has been considered as part of the existing rural development policies at the European, Spanish, and regional levels. Finally, a series of research- and policy- related recommendations are proposed

Quasi-homogeneous black hole thermodynamics

Although the fundamental equations of ordinary thermodynamic systems are known to correspond to first-degree homogeneous functions, in the case of non-ordinary systems like black holes the corresponding fundamental equations are not homogeneous. We present several arguments, indicating that black holes should be described by means of quasi-homogeneous functions of degree different from one. In particular, we show that imposing the first-degree condition leads to contradictory results in thermodynamics and geometrothermodynamics of black holes. As a consequence, we show that in generalized gravity theories the coupling constants like the cosmological constant, the Born-Infeld parameter or the Gauss-Bonnet constant must be considered as thermodynamic variables

Effects of whey protein concentrate on shelf life of cookies using corn and sunflower oils

The objective of this work was to study the effect of whey protein concentrate (WPC) on shelf life of cookies using corn and sunflower oils as fat source. Wheat flour was partially replaced by WPC with levels of 5, 7.5, 10 and 15 %. A User Defined Design was used and the three following responses were measured: peroxide index (meqO2/kg), flavour (score from 1-10) and rancidity (detectable and non-detectable) at 0, 7, 14, 21 and 70 days of storage. Results show that during storage peroxide index (PI) increases in all cookies samples. However a significant decrease was found when corn oil was used instead of sunflower oil and when the level of WPC goes from 0% to 15%. Regarding sensory evaluation, all cookies were evaluated as acceptable (scored flavour ≥ 6) and no rancid flavour was perceived, except for two samples which were assigned with 5 and rancid flavour was considered as detectable; these samples correspond to cookies evaluated at day 70, elaborated with sunflower oil and the lowest dose of WPC. No significant differences were found in cookies flavour prepared with different oils. On the other hand and relative to the level of WPC replacement, differences were found by the panel at days 0 and 7, a reduction in assigned score when WPC dose was increased, however this difference was not significant in the subsequent assessment days. According to research results, an increase in stability was clearly obtained in cookies elaborated with corn oil and the highest concentration of WPC.Fil: Erben, Melina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Sanchez, Hugo Diego. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; ArgentinaFil: Osella, Carlos Alberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentin

Curvature as a Measure of the Thermodynamic Interaction

We present a systematic and consistent construction of geometrothermodynamics by using Riemannian contact geometry for the phase manifold and harmonic maps for the equilibrium manifold. We present several metrics for the phase manifold that are invariant with respect to Legendre transformations and induce thermodynamic metrics on the equilibrium manifold. We review all the known examples in which the curvature of the thermodynamic metrics can be used as a measure of the thermodynamic interaction

The determinants of changes in the organization of production: Evidence from Spanish plant-level data

In this paper we empirically examine the determinants of changes in the organization of production using detailed information on a data set from a new plant-level survey of 1003 plants covering the full range of manufacturing industries in Spain. In particular, and among many other things, survey respondents were asked how service outsourcing practices had changed in the last three years. The answer to this question is indicative of the changes in the importance of backward integration for each of the plants studied. Using other information provided in the survey, we relate the reported changes in outsourcing to changes in other relevant dimensions as possible determinants of the boundaries of the firm. These dimensions are: plant size, downstream market power, cost of inputs, price and quality of the final good and technological progress. Our findings show that outsourcing increases are strongly positively correlated with increases in market share and in market competition. We also find that outsourcing increases when plants face simultaneous increases in product quality and product prices and that it decreases when plants face simultaneous increases in market share and market competition. Finally, we find that multi-plant and one-plant firms adjust their outsourcing practices differently to outside changes. Since neither TCE nor PRT theories of vertical integration fully explain the patterns found in our data, we close this paper by following Adam Smith's claim that the extent of the market seems to be the only factor consistently limiting the degree of specialization in our setting.outsourcing; vertical integration; competition; manufacturing plants;

Nonconventional Ca(OH) ₂ treatment of bamboo for the reinforcement of cement composites

This study compares the structural and morphological changes in Guadua angustifolia Kunth (GAK) fiber prepared in three different ways (chips, barkless and crushed) when non-conventional alkaline treatment is applied. Moreover, it shows the improvement of mechanical properties of cement composites reinforced with these treated fibers. The three different preparations of Guadua were treated with a saturated solution of calcium hydroxide (5%) at 125 °C and 1.25 kPa for 3 h to remove non-cellulosic compounds. Then, their chemical, morphological, and structural properties were examined. The fibers exhibiting the higher delignification rate were selected to prepare cement composite boards, whose mechanical properties were successively compared with those of composites reinforced with untreated G. angustifolia fibers. The water/cement ratios of the cement mixed with the Ca(OH)2-treated and the untreated fibers were, respectively, around 0.3 and 0.25. The flexural strength and toughness of the two composites were evaluated after 7, 28, and 90 days of curing. The calcium hydroxide treatment showed higher efficiency in removing non-cellulosic materials when performed on crushed bamboo; moreover, the mechanical properties of the composites reinforced with the treated fibers were higher than those mixed with the untreated ones. After 90 days of curing, the flexural strength increased by around 40% and the toughness became three times higher (p < 0.05). The mechanical improvement by the Ca(OH)2 treatment of G. angustifolia fibers demonstrates its potential for the fabrication of cement composites