Output subsidies and quotas under uncertainty and firm heterogeneity

This paper studies the relative efficiency of two kinds of regulations, quantity restrictions (quotas) and output subsidies, in an imperfectly competitive market under the existence of two sources of uncertainty: uncertainty in both costs and prices. We find that when the two sources of uncertainty are independently distributed, the output subsidy instrument has comparative advantage over the quantity instrument. However, when we take into account the possibility of correlation between the random components and across firms marginal costs, we find that a positive (negative) correlation tends to favor the quantity (subsidy) instrument. Finally, we show that when the correlation is positive, it is possible to find situations in which the quantity instrument has comparative advantage over the subsidy instrument.Cost uncertainty, demand uncertainty, firm heterogeneity, output subsidy and quantity instruments

How to automate a kinematic mount using a 3D printed Arduino-based system

We demonstrate a simple, flexible and cost-effective system to automatize most of the kinematic mounts available nowadays on the market. It combines 3D printed components, an Arduino board, stepper motors, and simple electronics. The system developed can control independently and simultaneously up to ten stepper motors using commands sent through the serial port, and it is suitable for applications where optical realignment using flat mirrors is required on a periodic basis.Comment: 9 pages, 8 figure

Optical sectioning in induced coherence tomography with frequency-entangled photons

We demonstrate a different scheme to perform optical sectioning of a sample based on the concept of induced coherence [Zou et al., Phys. Rev. Lett. 67, 318 (1991)]. This can be viewed as a different type of optical coherence tomography scheme where the varying reflectivity of the sample along the direction of propagation of an optical beam translates into changes of the degree of first-order coherence between two beams. As a practical advantage the scheme allows probing the sample with one wavelength and measuring photons with another wavelength. In a bio-imaging scenario, this would result in a deeper penetration into the sample because of probing with longer wavelengths, while still using the optimum wavelength for detection. The scheme proposed here could achieve submicron axial resolution by making use of nonlinear parametric sources with broad spectral bandwidth emission.Comment: Published version. 11 pages, 9 figure

Effect of a long-term consumption of two healthy dietary models on the progression of carotid atherosclerosis in patients with coronary heart disease

Antecedentes La enfermedad cardiovascular (ECV) continúa siendo la principal causa de mortalidad en los países desarrollados siendo, la enfermedad coronaria, la principal causa de todas sus manifestaciones. Aunque el manejo de los factores de riesgo cardiovascular tradicionales, tales como la hipertensión arterial, la diabetes mellitus tipo 2 (DM2), o el tabaquismo, juega un papel crucial en la prevención de eventos primarios y recurrencias de ECV, no se logra, en la práctica clínica, reducir por completo el riesgo de recurrencia de eventos cardiovasculares en pacientes que presentan enfermedad coronaria ya establecida. Por tanto, la búsqueda de biomarcadores de enfermedad que permitan mejorar el diagnóstico y pronóstico de estos pacientes, así como el desarrollo de nuevas terapias, constituyen los principales objetivos de investigación cardiovascular. En este sentido, el estilo de vida y los hábitos dietéticos han demostrado ser un potente modulador en el riesgo cardiovascular. Sin embargo, actualmente no existe un consenso sobre el mejor patrón dietético en el contexto de prevención secundaria ECV. La dieta mediterránea es un modelo de dieta reconocido por sus beneficios para la salud. Si bien, la eficacia de la dieta mediterránea en la reducción del riesgo cardiovascular se ha demostrado, hasta la fecha, sólo en prevención primaria con alto riesgo cardiovascular. La evaluación del grosor de la íntima-media de ambas arterias carótidas comunes (GIM-CC), a través de técnicas de ultrasonido en modo B, constituye un método clínico no invasivo y bien validado, considerado un marcador subrogado de aterosclerosis subclínica y un buen predictor de eventos cardiovasculares. Hipótesis En este proyecto de tesis doctoral, nuestra hipótesis de estudio es que el consumo a largo plazo de una dieta mediterránea rica en aceite de oliva virgen extra, en comparación con una dieta cardiosaludable baja en grasas y rica en carbohidratos complejos, produciría una mejoría en el grado de aterosclerosis carotídea, evaluada mediante la determinación del GIM-CC, en pacientes con enfermedad coronaria establecida. Este efecto podría explicarse por el potencial beneficio de los componentes de la dieta mediterránea en la patogénesis de la aterosclerosis. La hipótesis nula es que nuestro estudio no logre demostrar diferencias en el GIM-CC entre ambos modelos dietéticos. Objetivos Determinar si el consumo a largo plazo de una dieta mediterránea rica en aceite de oliva virgen extra, en comparación con una dieta baja en grasas y rica en carbohidratos complejos, reduciría el grado de aterosclerosis carotídea, mediante la evaluación del grosor de la íntima-media de ambas arterias carótidas comunes, en pacientes con enfermedad coronaria establecida. Objetivos secundarios: - Analizar el efecto del consumo a largo plazo de una dieta mediterránea rica en aceite de oliva virgen extra, en comparación con una dieta baja en grasas y rica en carbohidratos complejos, en marcadores relacionados con la progresión de la aterosclerosis, como el número y la altura de placas carotídeas en pacientes con enfermedad coronaria establecida. - Evaluar la contribución de diferentes factores, tanto relativos a la dieta (composición en macronutrientes e ingesta energética) como inherentes al propio paciente (parámetros antropométricos, clínicos y bioquímicos) en los cambios en el grosor de la íntima-media de ambas arterias carótidas comunes tras la ingesta de ambas intervenciones dietéticas. Población, diseño y metodología El estudio CORDIOPREV es un ensayo clínico aleatorizado, simple ciego, en pacientes con enfermedad coronaria establecida. Del total de pacientes incluidos en el estudio (n = 1002), 939 completaron la evaluación del GIM-CC al inicio del estudio, siendo aleatorizados a seguir una dieta mediterránea (35% de grasas, 22% ácidos grasos monoinsaturados y 55% de carbohidratos). Se realizaron medidas del GIM-CC a los 5 y a los 7 años de seguimiento, así como la cuantificación del número y altura de placas carotídeas. Durante el seguimiento se evaluaron cambios antropométricos, bioquímicos, así como la cuantificación plasmática de ácidos grasos como biomarcador de adherencia a ambos modelos dietéticos. Resultados El consumo a largo plazo (5 años) de un modelo de dieta mediterránea produjo una reducción del GIM-CC, en comparación con los valores basales, con un descenso medio de -0,027 ± 0,008 mm; (p 55% carbohydrate). Measurements of IMT-CC were performed at 5 and 7 years of follow-up, as well as quantification of carotid plaque height and number. During follow-up, anthropometric and biochemical changes were assessed, as well as plasma fatty acid quantification as a biomarker of adherence to both dietary models. Results Long-term consumption of a Mediterranean diet pattern (5 years) resulted in a reduction in IMT-CC, compared to baseline, with a mean decrease of -0.027 ± 0.008 mm; (p <0.001), which was maintained at 7 years (mean decrease of -0.031 ± 0.008 mm; p <0.001). The low-fat diet had no effect on IMT-CC. In addition, the Mediterranean diet resulted in a greater reduction in carotid IMT-CC and carotid plaque height compared to the low-fat diet during the follow-up (5 and 7 years). Multiple linear regression analyses showed that baseline IMT-CC had the strongest association with changes in IMT-CC after dietary intervention. Conclusions Long-term consumption of a Mediterranean diet, rich in extra virgin olive oil, compared to a low-fat diet rich in complex carbohydrates, reduces carotid atherosclerosis by inducing a reduction in the intima-media thickness of both common carotid arteries in patients with established coronary artery disease. These results reinforce the clinical benefits of the Mediterranean diet in the context of CVD in secondary prevention

Espesores de la Facies Keuper en la Rama Castellana de la Cordillera Ibérica , Prebético y Subbético frontal

Durante el período comprendido entre junio de 1988 y de 1989, una UTE de ADARO-INTECSA se dedicó a la realización del Proyecto denominado Ibérica-Levante, dentro del Proyecto ERA de la Empresa Nacional de Residuos Radiactivos (ENRESA), destinado a la búsqueda de emplazamientos rocosos aptos para un eventual almacenamiento, fundamentalmente en las intercalaciones de halita de la facies Keuper. Este artículo recoge parte de las conclusiones obtenidas

Experimental investigation and modelling of biodiesel combustion in engines with late direct injection strategy

The combination of alternate fuels, such as biodiesel, and low-temperature combustion (LTC) constitutes a promising solution to reduce pollutant emission and to avoid dependence on fossil fuels. However, this concept requires additional research to optimise LTC of biodiesel over wider operating ranges, specifically including the implementation of numerical models to assist in the development of these engines. In this work, an experimental analysis was carried out assessing both thermal performance and emissions derived from the LTC of diesel/biodiesel blends with late direct injection. Furthermore, this analysis allowed implementing a predictive tool to characterise in-cylinder pressure trace under this operation strategy. This model was coupled with an empirical law to simulate heat release during the combustion process. Least squares method was applied to fit this empirical law to experimental data involving different conditions in terms of percentages of rapeseed biodiesel in the fuel blend, rotational speed, fuel/air equivalence ratio and percentages of external exhaust gas recirculation. To build the predictive model, a multiple regression methodology was used to correlate the law parameters with the operating conditions. Finally, a validation process based on the simulation of in-cylinder pressure trace was developed, revealing that the predictions agreed well with the experimental data. This suggests that the proposed model is able to satisfactorily predict the LTC of diesel/biodiesel blends within the test range.Junta de Andalucía - Consejería de Economía AT17-5934-USUniversidad de Cádiz PB2022-04

Mechanical analysis of Genoa 03 stirling engine

Due to the new technologies development based on renewable sources of energy, in recent years Stirling engines have become very important in the energetic sector. Many of them do not allow the use of fluid lubricants and, thus, the effect of friction losses is important. For this purpose, a mathematical model has been developed based on the force balance in the crankshaft using the pressure distribution in the cylinders. The aim of this work is to characterize the mechanical losses in a Genoa 03 Stirling engine using a numerical model and experimentally via the drag method. The results of this model have been compared with those obtained experimentally on Genoa 03 Stirling engine. In the experimental results, a proportional increase in friction torque due to the average pressure and the speed of the crankshaft is observed. The first of these is caused by an increase of dry friction forces and the second, by the viscous friction between the working fluid and the inner walls of the engine. Also in this paper, irreversible processes in a beta type Stirling engine have been investigated in order to highlight the impact of losses on mechanical power and its performance. This article develops the first study of the mechanical losses of Genoa 03 experimental Stirling engine, which has an output power of 3 kW. Although the model response follows the same trends as the experiments, those simplifications provide errors which become more significant as the engine speed increases.Ministerio de Economía y Competitividad ENE2013-43465-

Cambio climático y paleohidrogeología

El concepto de almacenamiento geológico profundo para residuos radiactivos de alta actividad o con radionucleidos de vida larga cifra una parte importante de su seguridad a largo plazo en el comportamiento del medio geológico. El inventario de fenómenos, sucesos y procesos (FEPs) a tener en cuenta en la evaluación del almacenamiento permite agrupar los factores que intervienen en la evolución del sistema geológico en dos grupos: los que denominamos factores geodinámicos internos, cuyo origen se encuentra en la corteza terrestre y en el manto, y los factores geodinámicos externos, que dependen de manera más o menos directa de la radiación solar y de la composición y dinámica de los fluidos terrestres, en particular de la atmósfera y de la hidrosfera

Relevant aspects for an EF3-Evaluation of e-cognocracy

The search for an appropriate response to the new challenges and needs posed by the Knowledge Society in the area of public decisions has led to the development of a number of participation models whose value must be assessed and analysed in an integral manner. Using a theoretical model based on structural equations, the present work identifies the relevant factors for an EF3-approach to the democracy model named e-Cognocracy: it comprises a conjoint evaluation of its effectiveness (doing what is right), efficacy (achieving goals) and efficiency (doing things correctly). The model was applied to a real-life e-Cognocracy experience undertaken in the municipality of Cadrete, Zaragoza. The evaluation resulted in the extraction and identification of a series of relationships that allow the advancement of an EF3-participation acceptance model, in line with the TAM model of Davis and the work of Delone and MacLean, which can be used for the integral evaluation of any e-participation model

A Technique for Distributed Systems Specification

In this paper we show how an object-oriented specification language is usefvl for the specification of distributed systems. The main constructors in this language are the objects. An object consists of a state, a behaviour and a set of transition rules between states. The specification is composed by three sections: definition of algebraic data types to represent the domain of object attributes, definition of classes that group objects with common features, and definition of relationships among classes. We show two possible styles for defining the behaviour of objects, in one hand we use a transition system (state oriented) and in the other hand we use an algebraic model of processes description (constraint oriented). We illustrate the paper with the specification of the dining philosophers problem, a typical example in distributed programming