239 research outputs found
"Competing Micro Economic Theories Of Industrial Profits: An Empirical Approach"
Contrary to the impression given by most textbooks, microeconomics is not a homogeneous discipline. At least two major alternative theories exist which account for the long-run behavior of industrial prices and the between economic sectors in ways which are distinct from standard neoclassical explanations. Both Post Keynesian and Classical (Marxian/NeoRicardian) approaches to economics have developed a growing literature on microfoundations in recent years (see, e.g. Eichner, 1985; Dumenil & Levy, 1985).
Low temperature dielectric relaxation in ordinary perovskite ferroelectrics: enlightenment from high-energy x-ray diffraction
Ordinary ferroelectrics exhibit a second order phase transition that is characterized by a sharp peak in the dielectric permittivity at a frequency-independent temperature. Furthermore, these materials show a low temperature dielectric relaxation that appears to be a common behavior of perovskite systems. Tetragonal lead zirconate titanate is used here as a model system in order to explore the origin of such an anomaly, since there is no consensus about the physical phenomenon involved in it. Crystallographic and domain structure studies are performed from temperature dependent synchrotron x-ray diffraction measurement. Results indicate that the dielectric relaxation cannot be associated with crystallographic or domain configuration changes. The relaxation process is then parameterized by using the Vogel–Fulcher–Tammann phenomenological equation. Results allow us to hypothesize that the observed phenomenon is due to changes in the dynamic behavior of the ferroelectric domains related to the fluctuation of the local polarization.Postprint (author's final draft
Classical and Neoclassical Elements in Industrial Organization
Industrial organization studies of pricing are examined, focusing on the formative debates of 1950-70. It is argued that most of these studies unknowingly adopted a mixture of classical and neoclassical theory, leading to three types of confusions. First, over what measure of profitability is equalized in competitive equilibrium. Second, over what period of time profitability differentials must be studied. Third, over the correct conclusions to be drawn for industry phenomena from firm studies of profitability. The paper concludes by questioning the practicability of a purely neoclassical theoretical grounding for industrial economists, since they abandon this approach in their empirical work.
Evaluación de algunos efectos de la extracción tradicional de bromelias sobre la herpetofauna de los bosques de Chanal, Chiapas
During the celebration of Niño Florero in Chiapas every December, bromeliads are collected to form floral offerings to Baby Jesus. In this process amphibians and reptiles are killed causing losses of those organisms in the pine-oak forests. Fieldwork was carried out in the forests of Chanal, Chiapas; and consisted of direct sampling of bromeliads and interviews to plant collectors. We found that the most sacrificed animal is an endemic species, Abronia lythrochila. We propose three conservation strategies to achieve sustainability in the long term: volume reduction of bromeliads’ extraction, environmental education workshops and the establishment of protected zones.During the celebration of Niño Florero in Chiapas every December, bromeliads are collected to form floral offerings to Baby Jesus. In this process amphibians and reptiles are killed causing losses of those organisms in the pine-oak forests. Fieldwork was carried out in the forests of Chanal, Chiapas; and consisted of direct sampling of bromeliads and interviews to plant collectors. We found that the most sacrificed animal is an endemic species, Abronia lythrochila. We propose three conservation strategies to achieve sustainability in the long term: volume reduction of bromeliads’ extraction, environmental education workshops and the establishment of protected zones
Extra-Virgin Olive Oil Modifies the Changes Induced in Non-Nervous Organs and Tissues by Experimental Autoimmune Encephalomyelitis Models
This study reveals the existence of oxidative stress (reactive oxygen species (ROS)) in non-nervous organs and tissues in multiple sclerosis (MS) by means of a model of experimental autoimmune encephalomyelitis (EAE) in rats. This model reproduces a similar situation to MS, as well as its relationship with intestinal microbiota starting from the changes in bacterial lipopolysaccharide levels (LPS) in the outer wall of the gram-negative bacteria. Finally, the administration of extra-virgin olive oil (EVOO), hydroxytirosol (HT), and oleic acid (OA) exert beneficial effects. Twenty-five Dark Agouti two-month-old male rats, weighing around 190 g, were distributed into the following groups: Control, EAE (experimental autoimmune encephalomyelitis group), EAE + EVOO, EAE + HT, and EAE + OA. The glutathione redox system with the EAE was measured in heart, kidney, liver, and small and large intestines. The LPS and the correlation with oxidative stress in the small and large intestines were also investigated. The results showed that (1) the oxidative damage in the EAE model affects non-nervous organs and tissues; (2) The LPS is related to inflammatory phenomena and oxidative stress in the intestinal tissue and in other organs; (3) The administration of EVOO, HT, and OA reduces the LPS levels at the same time as minimizing the oxidative damage; (4) EVOO, HT, and OA improve the disease’s clinical score; and (5) on balance, EVOO offers a better neuroprotective effect
Cytokines in clinical cancer immunotherapy
Cytokines are soluble proteins that mediate cell-to-cell communication. Based on the discovery of the potent anti-tumour activities of several pro-inflammatory cytokines in animal models, clinical research led to the approval of recombinant interferon-alpha and interleukin-2 for the treatment of several malignancies, even if efficacy was only modest. These early milestones in immunotherapy have been followed by the recent addition to clinical practice of antibodies that inhibit immune checkpoints, as well as chimeric antigen receptor T cells. A renewed interest in the anti-tumour properties of cytokines has led to an exponential increase in the number of clinical trials that explore the safety and efficacy of cytokine-based drugs, not only as single agents, but also in combination with other immunomodulatory drugs. These second-generation drugs under clinical development include known molecules with novel mechanisms of action, new targets, and fusion proteins that increase half-life and target cytokine activity to the tumour microenvironment or to the desired effector immune cells. In addition, the detrimental activity of immunosuppressive cytokines can be blocked by antagonistic antibodies, small molecules, cytokine traps or siRNAs. In this review, we provide an overview of the novel trends in the cytokine immunotherapy field that are yielding therapeutic agents for clinical trials
Mineria de datos en inteligencia de negocios
Este proyecto tiene por objetivos: [a] definir un marco teórico que permita determinar de qué manera, los sistemas inteligentes puede utilizarse para descubrir automáticamente descripciones cualitativas de una base de datos que mejoren la calidad de la inteligencia de negocio, [b] determinar la calidad (por contraste con expertos del dominio) del conocimiento cualitativo inferido automáticamente y [c] desarrollar técnicas y fases metodológicas que mejoren el proceso de minería de datos con énfasis en la inteligencia de negocio.Eje: Agentes y Sistemas InteligentesRed de Universidades con Carreras en Informática (RedUNCI
Mineria de datos en inteligencia de negocios
Este proyecto tiene por objetivos: [a] definir un marco teórico que permita determinar de qué manera, los sistemas inteligentes puede utilizarse para descubrir automáticamente descripciones cualitativas de una base de datos que mejoren la calidad de la inteligencia de negocio, [b] determinar la calidad (por contraste con expertos del dominio) del conocimiento cualitativo inferido automáticamente y [c] desarrollar técnicas y fases metodológicas que mejoren el proceso de minería de datos con énfasis en la inteligencia de negocio.Eje: Agentes y Sistemas InteligentesRed de Universidades con Carreras en Informática (RedUNCI
Variability and power enhancement of current controlled resistive switching devices
Producción CientíficaIn this work, the unipolar resistive switching behaviour of Ni/HfO2/Si(n+) devices is studied. The structures are characterized using both current and voltage sweeps, with the device resistance and its cycle-to-cycle variability being analysed in each case. Experimental measurements indicate a clear improvement on resistance states stability when using current sweeps to induce both set and reset processes. Moreover, it has been found that using current to induce these transitions is more efficient than using voltage sweeps, as seen when analysing the device power consumption. The same results are obtained for devices with a Ni top electrode and a bilayer or pentalayer of HfO2/Al2O3 as dielectric. Finally, kinetic Monte Carlo and compact modelling simulation studies are performed to shed light on the experimental results.Junta de Andalucía - FEDER (B-TIC-624-UGR20)Consejo Superior de Investigaciones Científicas (CSIC) (project 20225AT012)Ramón y Cajal (grant RYC2020-030150-I
Planeación y estrategia de Ferris en el simulador de negocios capstone
En este documento se presenta el trabajo realizado en el simulador de negocios Capstone, en donde se dirigió una empresa de sensores llamada Ferris. Se presenta la planeación estratégica que se aplicó, su desarrollo y los resultados.ITESO, A.C
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