Ambiguity Aversion, the Equity Premium and the Welfare Costs of Business Cycles

We examine the potential importance of consumer ambiguity aversion for asset prices and how consumption ‡fluctuations influence consumer welfare. First, considering a simple Mehra-Prescott-style endowment economy with a representative agent facing consumption fluctuations calibrated to match U.S. data, we study to what extent ambiguity aversion can deliver asset prices that are consistent with data: a high return on equity and a low return on riskfree bonds. For some configurations of preference parameters— a discount factor, a degree of relative risk aversion, and a measure of ambiguity aversion— we find that it can. Then, we use these parameter configurations to investigate how much consumers would be willing to pay to reduce endowment fluctuations to zero, thus delivering a Lucas-style welfare cost of fluctuations. These costs turn out to be very large: consumers are willing to pay over 10% of consumption in permanent terms.Ambiguity aversion; asset prices; business cycle

Landslide motion assessment including rate effects and thermal interactions: revisiting the Canelles landslide

The re-activation of a large (40 Mm3) landslide on the valley slopes of a reservoir motivated a research initiative to estimate the risk of a fast-sliding mass moving into the reservoir. A previous simplified analysis had suggested that a joint consideration of strain rate effects on friction and thermal pressurization phenomena in the sliding surface could provide a rational approach to answer the question raised. The paper describes first the capability of strain rate effects on friction to reproduce long-term creeping records of two real cases. The joint and coupled phenomena of creeping motion and thermal pressurization in shearing bands was incorporated into a material point method computational technique for hydromechanical analysis of porous materials. A representative cross section of the Canelles landslide was then analysed, profiting from previous finite element investigations of the landslide. It was found that a rapid rate of landslide acceleration could be a possibility under extreme external actions. However, it was also found that a moderate strain rate effect on the basal residual friction angle could create conditions that avoid the triggering of a fast motion.Peer ReviewedPostprint (author's final draft

Sciplore Mindmapping: Una forma fácil de organizar una revisión bibliográfica

Este tutorial, de carácter pedagógico, presenta de manera didáctica cómo organizar una revisión bibliográfica a través de mapas mentales utilizando el software libre SciPlore MindMapping. Este documento está diseñado para Investigadores, colaboradores estudiantes o cualquier persona que necesite realizar una revisión bibliográfica para realizar un trabajo de investigación.Mapas mentales, SciPlore Mindmapping,

Medellín imaginada desde la televisión. Los imaginarios en la serie de televisión “Muchachos a lo Bien”

Es innegable que la representación de la ciudad que aparece en los relatos audiovisuales tiende al estereotipo (la imagen de moda, los personajes de Medellín que aparecen en otras series de televisión, modelos, traficantes), sobretodo en los videos más vistos, los más impactantes. Y no es por asuntos temáticos, sino por asuntos de tratamiento y de narrativas; hasta de imaginarios. Es decir, las piezas audiovisuales tienden al mismo contenido. Sin embargo, para esta investigación, partimos del supuesto: la narrativa de “Muchachos a lo Bien” tiende a romper estos estereotipos y a presentar identidades más diversas que la mayoría de las narrativas propuestas en otras piezas.It is undeniable that the representation of the city that appears in the stories audiovisual tends to stereotype (the image of fashion, the characters in Medellin that appear in other television series, models, traffickers), especially in the videos most viewed, the most shocking. It is not by thematic issues, but by matters of treatment and narratives; until the imaginary. In other words, the pieces audiovisual tend to the same content

Notas: Ronald Dworkin y la democracia de partidos: Una propuesta de mejora

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La sostenibilidad de la política fiscal en América Latina: El caso de Colombia

Las finanzas del sector público colombiano mostraron déficits durante prácticamente todos los años del período 1980-1996. Este resultado no debe sorprender si se compara con la evolución fiscal de otros países de la región o del continente europeo en el mismo período, que también fue deficitaria.

Successful object encoding induces increased directed connectivity in presymptomatic early-onset Alzheimer's disease

Background: Recent studies report increases in neural activity in brain regions critical to episodic memory at preclinical stages of Alzheimer’s disease (AD). Although electroencephalography (EEG) is widely used in AD studies, given its non-invasiveness and low cost, there is a need to translate the findings in other neuroimaging methods to EEG. Objective: To examine how the previous findings using functional magnetic resonance imaging (fMRI) at preclinical stage in presenilin-1 E280A mutation carriers could be assessed and extended, using EEG and a connectivity approach. Methods: EEG signals were acquired during resting and encoding in 30 normal cognitive young subjects, from an autosomal dominant early-onset AD kindred from Antioquia, Colombia. Regions of the brain previously reported as hyperactive were used for connectivity analysis. Results: Mutation carriers exhibited increasing connectivity at analyzed regions. Among them, the right precuneus exhibited the highest changes in connectivity. Conclusion: Increased connectivity in hyperactive cerebral regions is seen in individuals, genetically-determined to develop AD, at preclinical stage. The use of a connectivity approach and a widely available neuroimaging technique opens the possibility to increase the use of EEG in early detection of preclinical AD.Postprint (author's final draft

A Sunscreen-Based Photocage for Carbonyl Groups

This is the peer reviewed version of the following article: M. Lineros-Rosa, M. A. Miranda, V. Lhiaubet-Vallet, Chem. Eur. J. 2020, 26, 7205, which has been published in final form at https://doi.org/10.1002/chem.202000123. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Photolabile protecting groups (PPGs) have been exploited in a wide range of chemical and biological applications, due to their ability to provide spatial and temporal control over light-triggered activation. In this work, we explore the concept of a new photocage compound based on the commercial UVA/UVB filter oxybenzone (OB; 2-hydroxy-4-methoxybenzophenone) for photoprotection and controlled release of carbonyl groups. The point here is that oxybenzone not only acts as a mere PPG, but also provides, once released, UV photoprotection to the carbonyl derivative. 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Light-induced controlled release of fragrance aldehydes from 1-alkoxy-9,10-anthraquinones for applications in functional perfumery. Flavour and Fragrance Journal, 21(3), 400-409. doi:10.1002/ffj.1728Levrand, B., & Herrmann, A. (2007). Controlled Light-Induced Release of Volatile Aldehydes and Ketones by Photofragmentation of 2-Oxo-(2-phenyl)acetates. CHIMIA International Journal for Chemistry, 61(10), 661-664. doi:10.2533/chimia.2007.661Griesbeck, A. G., Hinze, O., Görner, H., Huchel, U., Kropf, C., Sundermeier, U., & Gerke, T. (2012). Aromatic aldols and 1,5-diketones as optimized fragrance photocages. Photochemical & Photobiological Sciences, 11(3), 587. doi:10.1039/c2pp05286eBrinson, R. G., & Jones, P. B. (2004). Caged trans-4-Hydroxy-2-nonenal. Organic Letters, 6(21), 3767-3770. doi:10.1021/ol048478lBrinson, R. G., Hubbard, S. C., Zuidema, D. R., & Jones, P. B. (2005). Two new anthraquinone photoreactions. Journal of Photochemistry and Photobiology A: Chemistry, 175(2-3), 118-128. doi:10.1016/j.jphotochem.2005.03.027Blankespoor, R. L., DeVries, T., Hansen, E., Kallemeyn, J. M., Klooster, A. M., Mulder, J. A., … Vander Griend, D. A. (2002). Photochemical Synthesis of Aldehydes in the Solid Phase. The Journal of Organic Chemistry, 67(8), 2677-2681. doi:10.1021/jo025508uMcHale, W. A., & Kutateladze, A. G. (1998). An Efficient Photo-SET-Induced Cleavage of Dithiane−Carbonyl Adducts and Its Relevance to the Development of Photoremovable Protecting Groups for Ketones and Aldehydes. The Journal of Organic Chemistry, 63(26), 9924-9931. doi:10.1021/jo981697yLi, Z., Wan, Y., & Kutateladze, A. G. (2003). Dithiane-Based Photolabile Amphiphiles:  Toward Photolabile Liposomes1,2. Langmuir, 19(16), 6381-6391. doi:10.1021/la034188mMajjigapu, J. R. R., Kurchan, A. N., Kottani, R., Gustafson, T. P., & Kutateladze, A. G. (2005). 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Competitiveness of colombian departments observed from an economic geography perspective

ABSTARCT: In this paper, we analyze the regional competitiveness concept and its measurement using the old and New Trade Theory and the New Economic Geography. The analysis shows that the competitiveness has no sense when is applied to the goods market, while has sense (however, not in all situations) when is applied to the productive factors market. Contrary to most approaches and measurements of the competitiveness of Colombian departments, we show that is possible to obtain simple measures which, in addition to being consistent with the conceptual framework of economic geography, are the product of the combination of a small number of variables