Tobin's imperfect asset substitution in optimizing general equilibrium

In this paper, we present a dynamic optimizing model that allows explicitly for imperfect substitutability between different financial assets. This is specified in a manner which captures Tobin's (1969) view that an expansion of one asset's supply affects both the yield on that asset and the spread or "risk premium" between returns on that asset and alternative assets. Our estimates of this model on U.S. data confirm that some of the observed deviations of long-term rates from the expectations theory of the term structure can be traced to movements in the relative stocks of financial assets. The richer aggregate demand and asset specifications imply that there exists an additional channel of monetary policy. Our results suggest that central bank operations exercise a modest influence on the relative prices of alternative financial securities, and so exert an extra effect on long-term yields and aggregate demand separate from their effect on the expected path of short-term rates.Monetary policy ; Macroeconomics

Sticky-price models and the natural rate hypothesis

A major criticism of standard specifications of price adjustment in models for monetary policy analysis is that they violate the natural rate hypothesis by allowing output to differ from potential in steady state. In this paper we estimate a dynamic optimizing business cycle model whose price-setting behavior satisfies the natural rate hypothesis. The price-adjustment specifications we consider are the sticky-information specification of Mankiw and Reis (2002) and the indexed contracts of Christiano, Eichenbaum, and Evans (2005). Our empirical estimates of the real side of the economy are similar whichever price adjustment specification is chosen. Consequently, the alternative model specifications deliver similar estimates of the U.S. output gap series, but the empirical behavior of the gap series differs substantially from standard gap estimates.Monetary policy ; Prices

Detection of inter-turn faults in multi-phase ferrite-PM assisted synchronous reluctance machine

Inter-turn winding faults in five-phase ferrite-permanent magnet-assisted synchronous reluctance motors (fPMa-SynRMs) can lead to catastrophic consequences if not detected in a timely manner, since they can quickly progress into more severe short-circuit faults, such as coil-to-coil, phase-to-ground or phase-to-phase faults. This paper analyzes the feasibility of detecting such harmful faults in their early stage, with only one short-circuited turn, since there is a lack of works related to this topic in multi-phase fPMa-SynRMs. Two methods are tested for this purpose, the analysis of the spectral content of the zero-sequence voltage component (ZSVC) and the analysis of the stator current spectra, also known as motor current signature analysis (MCSA), which is a well-known fault diagnosis method. This paper compares the performance and sensitivity of both methods under different operating conditions. It is proven that inter-turn faults can be detected in the early stage, with the ZSVC providing more sensitivity than the MCSA method. It is also proven that the working conditions have little effect on the sensitivity of both methods. To conclude, this paper proposes two inter-turn fault indicators and the threshold values to detect such faults in the early stage, which are calculated from the spectral information of the ZSVC and the line currentsPeer ReviewedPostprint (published version

Effects of extraction pH of chia protein isolates on functional properties

The aim of this work was to study the effect of the extraction pH on the functional properties of chia protein isolates (CPI). Samples were named as CPI10 or CPI12, according to their extraction pH, 10 or 12, respectively. Functional properties were significantly modified by the extraction pH. Color properties revealed that CPI12 presented a lower L* (47.8 ± 0.9 for CPI10 and 30 ± 1 for CPI12). Besides, a higher b* value was obtained for CPI12 (7.0 ± 0.3 for CPI12 and 5.6 ± 0.7 for CPI10), as a result of a higher ash content. CPI12 showed a higher WAC probably due to a higher exposure of polar amino acids (4.4 ± 0.1 g/g and 6.0 ± 0.2 g/g), whereas CPI10 showed a higher ability to bind oil (7.1 ± 0.2 g/g and 6.1 ± 0.2 g/g for CPI10 and CPI12, respectively). CPI10 proved more appropriate as an emulsion stabilizer than CPI12, which could be due to its higher surface hydrophobicity, protein solubility and negative net charge. The d4,3 (μm) was 29.5 ± 0.4 and 20.4 ± 0.3 in emulsions stabilized with CPI12 and CPI10, respectively. Although both isolates underwent heat gelation, they exhibited a weak gel behavior. Overall, CPI10 may be more suitable for the food industry as a meat replacer or extender.Fil: López, Débora Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Departamento de Química y Física. Área Fisicoquímica; ArgentinaFil: Ingrassia, Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Departamento de Química y Física. Área Fisicoquímica; ArgentinaFil: Busti, Pablo Andres. Universidad Nacional de Rosario; ArgentinaFil: Wagner, Jorge Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Spelzini, Darío. Universidad Nacional de Rosario; Argentina. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; ArgentinaFil: Boeris, Valeria. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario; Argentin

Improvements in CO2 Booster Architectures with Different Economizer Arrangements.

CO2 transcritical booster architectures are widely analyzed to be applied in centralized commercial refrigeration plants in consonance with the irrevocable phase-out of HFCs. Most of these analyses show the limitations of CO2 cycles in terms of energy e ciency, especially in warm countries. From the literature, several improvements have been proposed to raise the booster e ciency in high ambient temperatures. The use of economizers is an interesting technique to reduce the temperature after the gas cooler and to improve the energy e ciency of transcritical CO2 cycles. The economizer cools down the high pressure’s line of CO2 by evaporating the same refrigerant extracted from another point of the facility. Depending on the extraction point, some configurations are possible. In this work, di erent booster architectures with economizers have been analyzed and compared. From the results, the combination of the economizer with the additional compressor allows obtaining energy savings of up to 8.5% in warm countries and up to 4% in cold countries with regard to the flash-by-pass arrangement and reduce the volumetric displacement required of the MT compressors by up to 37%

Experimental determination of the optimum working conditions of a transcritical CO2 refrigeration plant with integrated mechanical subcooling

Subcooling methods for transcritical CO2 plants are being studied in order to improve their behavior. Among them, the Integrated Mechanical Subcooling system is one of the most promising owing that performs with high efficiency and it is a total-CO2 system. This work presents the experimental determination of the optimum working conditions of a transcritical CO2 plant working with an integrated mechanical subcooling system. The plant was tested at different pressure and subcooling conditions in order to optimize the COP of the plant and determine the optimal conditions for three ambient temperatures 25.0 °C, 30.4 °C and 35.1 °C and evaporation levels between −15.6 °C and −4.1 °C. Optimum operating conditions were determined and two correlations are proposed to determine the optimal pressure and subcooling as function the gas-cooler outlet temperature and the evaporation level

Liquid bridge breakages aboard SPACELAB-D1

The study of the stability of long liquid columns under microgravity was the purpose of one of the experiments carried out aboard Spacelab-Dl. In this paper a preliminary analysis of this experiment, mainly concerning the different liquid column breakages, is presented. As shown in the paper, the behaviour, both static and dynamic, of long liquid bridges can be accurately predicted by using available theoretical models

(PVA/chitosan/fucoidan)-ampicillin: A bioartificial polymeric material with combined properties in cell regeneration and potential antibacterial features

Chitosan, fucoidan, and polyvinyl alcohol are categorized as polymers with biomedical applications. Ampicillin, on the other hand, is considered as an important antibiotic that has shown effectivity in both gram-positive and gram-negative micro-organisms. The aforementioned polymers possess unique properties that are considered desirable for cell regeneration although they exhibit drawbacks that can affect their final application. Therefore, films of these biomaterials were prepared and they were characterized using FTIR, SEM, XRD, degree of swelling and solubility, and MTT assay. The statistical significance of the experiments was determined using a two-way analysis of variance (ANOVA) with p < 0.05. The characterization techniques demonstrated that the obtained material exhibits properties suitable for cell regeneration, and that a higher concentration of natural polymers promotes cells proliferation to a greater extent. The presence of PVA, on the other hand, is responsible for matrix stability and dictates the degree of swelling and solubility. The SEM images demonstrated that neither aggregations nor clusters were formed, which is favorable for the biological properties without detrimental to the morphological and physical features. Cell viability was comparatively similar in samples with and without antibiotic, and the physical and biological properties were not negatively affected. Indeed, the inherent bactericidal effect of chitosan was reinforced by the presence of ampicillin. The new material is an outstanding candidate for cell regeneration as a consequence of the synergic effect that each component provides to the blend. © 2019 by the author.Ministry of Education, Youth and Sports of the Czech Republic, Program NPU I [LO1504