The Impact of Public and Private Job Training in Colombia

The authors present various matching estimators of the impact on earnings for individuals who attended public and private job training programs in Colombia. The authors estimate propensity scores by controlling for the wide variety of personal and socioeconomic background variables of those individuals. The effect of training, measured by the mean impact of the treatment on the treated, shows that: (i) for youths, no institution has a significant impact in the short or long run except private institutions for males; the scope of the data, however, limits the reliability of the result; (ii) for adult males, neither SENA nor the other public institutions have a significant impact in the short or long run; (iii) for SENAtrained adult females there are positive but not significant impacts in the short run and greater and close to significant effects in the long run. All other public institutions have a higher impact that is significant in the long-run; (iv) for adults trained at private institutions there are large and significant effects in both the short and long run, but for adult males in the short run the effects are smaller and only barely significant. In addition, neither short nor long courses provided by SENA seem to have a significant impact on earnings. In general, females benefit more from both short and long courses than males. Finally, a cost-benefit analysis shows that under the assumption of direct unitary costs equal to SENA, private institutions are more profitable than public institutions, which are in turn more profitable than SENA.Program evaluation, selection bias, job training programs

Probing Split Supersymmetry with Cosmic Rays

A striking aspect of the recently proposed split supersymmetry is the existence of heavy gluinos which are metastable because of the very heavy squarks which mediate their decay. In this paper we correlate the expected flux of these particles with the accompanying neutrino flux produced in inelastic $pp$ collisions in distant astrophysical sources. We show that an event rate at the Pierre Auger Observatory of approximately 1 yr$^{-1}$ for gluino masses of about 500 GeV is consistent with existing limits on neutrino fluxes. The extremely low inelasticity of the gluino-containing hadrons in their collisions with the air molecules makes possible a distinct characterization of the showers induced in the atmosphere. Should such anomalous events be observed, we show that their cosmogenic origin, in concert with the requirement that they reach the Earth before decay, leads to a lower bound on their proper lifetime of the order of 100 years, and consequently, to a lower bound on the scale of supersymmetry breaking, $\Lambda_{\rm SUSY} >2.6 \times 10^{11}$ GeV. Obtaining such a bound is not possible in collider experiments.Comment: Version to be published in Phys. Rev.

Investification in Latin America: problematising the letting market in the Chilean case

Se introduce el fenómeno de la inversionistificación como marco de análisis crítico para desentrañar las problemáticas asociadas al aumento de propietarios en un mercado de arriendos reducidos como parte de factores que inciden en el aumento de precio de arriendos. El contexto neoliberal chileno con un mercado de arriendos desregulados ofrece interesantes alcances al problema de la vivienda y el arriendo en ciudades de la región. El método se divide en dos partes. A nivel nacional se ha utilizado un método estadístico descriptivo a partir de la encuesta CASEN entre 2009 y 2017 para detectar cuánto ha variado la cantidad de hogares que perciben ingresos por arriendo de propiedades urbanas en este periodo. Para profundizar el análisis, se selecciona un barrio con heterogeneidad en valores de arriendo para estudiarlo mediante técnicas de evaluación de rentabilidad financiera (Yield y VAN). Los resultados de este estudio indican que ha aumentado la concentración de ingresos por arriendo de propiedades urbanas en el 10% más rico y que en el barrio estudiado para todos los casos se observa una rentabilidad financiera alta. Con esto se demuestra la existencia de inversionistificación en Santiago y se ofrecen algunas alternativas de política pública.The article introduces how investification serve as an analytical framework for unpinning the increase of the buy-to-let phenomenon in a reduced letting market that produces a rise in letting prices. The Chilean neoliberal context and the dis-regulated condition of property-rent markets provides a chance for reviewing the insights of how housing and letting are undermining the affordability in the Latin American region. The first part is centred on an explorative statistical analysis based on CASEN survey 2009-2017 to identify the variations in the household whose incomes come from letting urban properties. To deepen the analysis, the second part explores the financial profitability of letting business in a specific borough of Santiago. This analysis employs two financial methods: the Yield and the Net Present Value (NPV). The results indicate that there is a higher concentration of this type of business in the wealthiest 10% while the profitability of letting business is high. These results demonstrate the existence of investificacion in Santiago and some public policy alternatives are offered to engage in a broader international discussion

Investification en el mercado de la vivienda: estudio exploratorio en Santiago de Chile

El presente estudio aborda el fenómeno de la investificación en el mercado de arriendo del Gran Santiago. Para ello se utiliza un enfoque metodológico cuantitativo por regresiones geográficamente ponderadas. A través de la recopilación y análisis de datos de transacciones y de indicadores urbanos, se exploran los patrones de localización de inversiones residenciales con relación a funciones urbanas específicas a nivel de zonas censales. El análisis revela que la proximidad a instituciones de educación superior, la estabilidad en los precios de arriendo y la presencia de personas mayores son factores determinantes en la selección de propiedades para inversión. Estos hallazgos evidencian la transformación del paisaje urbano como espacios de renta para el capital y destaca la creciente segmentación socioespacial, subrayando así la necesidad de regulaciones que atiendan las implicancias del investification en la dinámica urbana del Gran Santiago.This study uses a quantitative methodological approach with geographically weighted regressions to address the phenomenon of investification in the Greater Santiago rental market. Using the collection and analysis of transaction data and urban indicators, the location patterns of residential investments are explored for specific urban functions at the census tract level. The analysis reveals that proximity to higher education institutions, stability in rental prices, and the presence of older adults are determining factors in the selection of investment properties. These findings evidence the transformation of the urban landscape as rental spaces for capital and highlight the growing socio-spatial segmentation, thus underlining the need for regulations that address the implications of investification in the urban dynamics of Greater Santiago

Cosmology from String Theory

We explore the cosmological content of Salam-Sezgin six dimensional supergravity, and find a solution to the field equations in qualitative agreement with observation of distant supernovae, primordial nucleosynthesis abundances, and recent measurements of the cosmic microwave background. The carrier of the acceleration in the present de Sitter epoch is a quintessence field slowly rolling down its exponential potential. Intrinsic to this model is a second modulus which is automatically stabilized and acts as a source of cold dark matter with a mass proportional to an exponential function of the quintessence field (hence realizing VAMP models within a String context). However, any attempt to saturate the present cold dark matter component in this manner leads to unacceptable deviations from cosmological data -- a numerical study reveals that this source can account for up to about 7% of the total cold dark matter budget. We also show that (1) the model will support a de Sitter energy in agreement with observation at the expense of a miniscule breaking of supersymmetry in the compact space; (2) variations in the fine structure constant are controlled by the stabilized modulus and are negligible; (3) ``fifth''forces are carried by the stabilized modulus and are short range; (4) the long time behavior of the model in four dimensions is that of a Robertson-Walker universe with a constant expansion rate (w = -1/3). Finally, we present a String theory background by lifting our six dimensional cosmological solution to ten dimensions.Comment: Version to be published in Physical Review

Reliability evaluation of III-V concentrator solar cells

Concentrator solar cells have been proposed as an interesting way of reducing the cost of photovoltaic electricity. However, in order to compete with conventional solar modules it is necessary not only to reduce costs but also to evaluate and increase the present reliability. Concentrator solar cells work at higher temperature, solar radiation and current stress than conventional solar cells and a carefully reliability analysis is needed. In this paper a reliability analysis procedure, that is being developed, is presented

Upper Main Sequence Stars with Anomalous Abundances. The HgMn stars HR 3273, HR 8118 HR 8567 and HR 8937

Este trabajo es parte de un estudio para verificar posibles tendencias de las abundancias en estrellas HgMn con los parámetros estelares, rotación y edad. Presentamos un análisis de las estrellas HR 3273, HR 8118, HR 8567 y HR 8937. Utilizamos espectros echelle tomados con el telescopio de 2.1 m del CASLEO y modelos de atmósferas de ATLAS9. El He resultó por debajo del valor solar para las estrellas HgMn. El O resultó levemente sobreabundante en HR 3273 y HR 8567. MgII resultó por debajo excepto para HR 8118. El SiII resultó aproximadamente solar en HR 8118 y HR 8937, y por debajo en HR 3273 y HR 8567. El Fe resultó levemente sobreabundante en HR 8118 y HR 8937 y subabundante en HR 3273 y HR 8567. Las especies Sc, Ti, Cr, Mn, Sr, Y y Zr resultaron sobreabundantes mientras que el Ni resultó estar por debajo del valor solar.This work is part of our current study for verifying a possible relation between abundances of HgMn stars with stellar parameters, rotation and age. We present an analysis of the stars HR 3273, HR 8118, HR 8567 and HR 8937. We used echelle spectra taken with the CASLEO 2.1 m telescope and ATLAS9 model atmospheres. HeI was underabundant for the HgMn stars. O was slightly underabundant in HR 3273 and HR 8567. MgII was underabundant except for HR 8118. SiII was close to solar in HR 8118 and HR 8937, and underabundant in HR 3273 and HR 8567. Fe was slightly underabundant in HR 3273 and HR 8567, and slightly overabundant in HR 8118 and HR 8937. The species Sc, Ti, Cr, Mn, Sr, Y and Zr were overabundant while Ni was underabundant.Fil: Saffe, Carlos. Consejo Nacional de Investigaciones Cientiâ­ficas y Tecnicas. Centro Cientifico Tecnologico San Juan. Instituto de Ciencias Astronomicas de la Tierra y del Espacio; ArgentinaFil: Nuñez, Natalia Edith. Consejo Nacional de Investigaciones Cientiâ­ficas y Tecnicas. Centro Cientifico Tecnologico San Juan. Instituto de Ciencias Astronomicas de la Tierra y del Espacio; ArgentinaFil: Levato, Orlando Hugo. Consejo Nacional de Investigaciones Cientiâ­ficas y Tecnicas. Centro Cientifico Tecnologico San Juan. Instituto de Ciencias Astronomicas de la Tierra y del Espacio; Argentin

Estudio sobre el consumo de alcohol y drogas en los estudiantes de las unidades educativas de la ciudad del Tena en el periodo 2013-2015

Showing the consumption of psychotropic substances as a public, social and economic health and the need for reliable, consistent and technically structured information, which serves as support for developing business projects, campaigns and other activities that reduce, and prevent the concienticen first use of such products, concerned about this problem this research work will serve as a tool to make decisions more focused to counteract this problem in students from schools in the city of Tena was prepared; scientific research methodology was used, specifically a descriptive method by which consumption levels especially snuff, alcohol was determined along with other psychotropic substances, besides the early age at which young students begin their consumption brought is identified by curiosity or because someone causes them this idea. The present research aims to identify the problem to somehow educate young people the negative effects on them and society.Mostrando el consumo de sustancias psicotrópicas como un problema de salud pública, social y económico y la necesidad de contar con información confiable, consistente y técnicamente estructurada, que sirva como sustento hábil para elaborar proyectos, campañas y demás actividades que disminuyan, concienticen y prevengan el inicio del consumo de dichos productos, preocupados por este problema se elaboró el presente trabajo investigativo que servirá como herramienta para tomar las decisiones más enfocadas para contrarrestar dicha problemática en los estudiantes de los colegios de la ciudad de Tena; para la investigación se empleó la metodología científica, específicamente un método descriptivo por el cual se determinó niveles de consumo especialmente de tabaco, alcohol junto a otras sustancias psicotrópicas, además se identifica la temprana edad en la que los jóvenes estudiantes empiezan sus consumos llevados por curiosidad o porque alguien les induce esta idea. Con la presente investigación se propone conocer el problema para de alguna manera concienciar a los jóvenes los efectos negativos que tienen sobre ellos y la sociedad

Reliability Improvement in III-V Concentrator Solar Cells by Means of Perimeter Protection

This paper presents the evolution in the strategy to assess the reliability of III-V solar cells and a new thermal ageing test carried out over GaAs single junction solar cells at three different temperatures (130, 150 and 170° C). The perimeter of the solar cells has been protected with silicone, which seems to be an effective way of enhancing the reliability of the solar cells. A preliminary analysis of the results indicates a mean time to failure (MTTF) one order of magnitude larger than the one obtained in a previous thermal test with the perimeter uncoated