Self-Selection Patterns among Return Migrants: Mexico 1990-2010

This paper analyzes the self-selection patterns among Mexican return migrants during the period from 1990 to 2010. Using census data, we can identify return migrants who have lived in the United States within the previous 5 years but who currently live in Mexico. To calculate the selection patterns, we non parametrically estimate the counterfactual wages that the return migrants would have experienced had they never migrated by using the wage structure of non migrants. We find evidence that the selection patterns change over time toward negative selection. For example, in 1990, the wages that the male return migrants would have experienced had they not migrated was 6 percent larger than the wages of male non migrants. However, by 2010, the difference had declined to -14 percent. The increasing negativity of the degree of selection is robust to the analysis of specific subgroups: rural and urban, men and women, and states with high migration rates and low migration rates. Moreover, the negative selection results for the period from 2000 to 2010 are robust to the use of different surveys that define a return migrant by using distinct characteristics. Additionally, we observe that the wages of return migrants are larger than those that the migrants would have obtained had they not migrated. This finding shows that migration has a positive effect on the Mexican economy.Mexican migration, self-selection, return migration, wages

Subjective Well-Being among Communities Left Behind by International Migrants

This article assesses the impact of international migration on the subjective well-being of communities of origin in Mexico. Using a representative national survey and an empirical strategy with instrumental variables, we find that higher migratory intensity, at the municipal level, increases life satisfaction among men and women. There is a negative effect on emotional states of women, but an improvement in emotional states of men. Without controlling for schooling, a variable affected by international migration, men have a lower satisfaction with their perspective of future. Overall, the evidence in Mexico shows that the effects of international migration in the communities of origin are complex and with differential effects based on gender

Bioremediation of a polycyclic aromatic hydrocarbons contaminated soil using an indigenous consortium

Polycyclic aromatic hydrocarbons (PAHs) include a group of organic priority pollutants of critical environmental and public health concern due to their toxic, genotoxic, mutagenic and carcinogenic properties. PAHs have been accumulated in the environment as a result of human activities. Bioremediation has become the most viable mechanism to reach the detoxification of contaminated sites. The objective of this study was to assess the capacity of an indigenous consortium enriched from an aged contaminated soil to biodegrade 16 PAHs, more concretely it was searched the complete removal of phenanthrene to CO2 and water.A PAHs degrading microbial consortium (OMC), isolated from a contaminated soil, was investigated for 16 PAHs biodegradation activity. The OMC consortium was able to biodegrade six of the 16 PAHs studied, reaching 100% for naphtalene acenaphthylene, acenaphthene, fluorine, phenanthrene, naphthalene, acenaphthylene, acenaphthene, anthracene and fluoranthene. However, 78.4 and 53.86 % were removed for anthracene and fluerenthrene respectively.Nine Strains were isolated from the OMC (PHE1,2,3,4,5,6,7,8,9). Isolated strains were tested to mineralise and in all cases the PHE concentration was drastically reduced. Once has been confirmed that indigenous bacteria were capable of degrading PAH and mineralising PHE were identified through 16S rDNA. Moreover, was proved the presence of genes including monooxygenase and dioxygenase by PCR amplification in the OMC and in the identified strains from the consortium. In OMC two of these genes were found: PAH RHDα GN and nahAC. However, in the isolated strains only one of the genes searched was identified: PAH RHDα GN, more specifically in Phe 8, Phe 4 and Phe 9.As result, it is shown that bacteria from a contaminated soil are active in biodegradation and mineralisation process, what makes the indigenous microbiota a powerful tool for bioremediation uses

¿Es realmente fácil unirse a la formalidad? Una aproximación con trayectorias laborales en el mercado laboral mexicano

More than half of Mexico's workforce is in informal economy; however, there are a high number of transitions from informal to formal employment in the short term, which has been interpreted as evidence that informality is an alternative to improve well-being. The main objective of this study is to analyze the employment conditions and job stability of employees who are inserted into the formal market, after starting their labor trajectory in the informal market. We use the Módulo de Trayectorias Laborales (MOTRAL) 2015, a survey with national representativeness of Mexican urban areas. We compare emplyment conditions and job stability in 2010 among formal employment using two groups: those who had their first job in informality and those who had their first job in formality. Transition matrices are built between first employment, employment in 2010, and 2015 to corroborate the high mobility found by previous literature; employment conditions and job stability are then analyzed with multivariate models. The results indicate that a significant proportion of those who started in informality subsequently had access to formal jobs. However, access to formal employment from informality occurs under conditions of disadvantages concerning access and job stability, without these subsequently disappearing. Then, the start of working life in informality is associated with permanent disadvantages in the labor market.Más de la mitad de la fuerza laboral mexicana se encuentra en la informalidad. Sin embargo, existe un elevado número de transiciones del empleo informal al empleo formal en el corto plazo, lo que se ha interpretado como evidencia de que la informalidad es una decisión óptima para incrementar el bienestar. El objetivo de este trabajo es analizar las condiciones de ingreso y estabilidad laboral de los empleados que se insertan a la formalidad, después de iniciar su trayectoria laboral en la informalidad. Se utiliza el Módulo de Trayectorias Laborales (MOTRAL) 2015, encuesta con representatividad nacional de las zonas urbanas mexicanas. Para ello se comparan las condiciones de ingreso y la estabilidad laboral en 2010 entre los trabajadores formales utilizando dos grupos: quienes tuvieron su primer empleo en la informalidad y quienes tuvieron su primer empleo en la formalidad. Se construyen matrices de transición entre el primer empleo, el empleo en 2010, y en 2015 para corroborar la alta movilidad encontrada por la literatura previa; posteriormente se analizan con modelos multivariados las condiciones de ingreso y la estabilidad laboral. Los resultados indican que una proporción significativa de quienes se iniciaron en la informalidad acceden posteriormente a empleos formales. Sin embargo, se encuentra que el acceso al empleo formal desde la informalidad ocurre en condiciones de desventajas en ingresos y contratación de largo plazo, sin que las desventajas desaparezcan posteriormente, por lo que el inicio de la vida laboral en la informalidad está asociado a desventajas permanentes en el mercado de trabajo

Creation of a complete horror level with its sound environment in Unreal Engine 4

Treball Final de Grau en Disseny i Desenvolupament de Videojocs. Codi: VJ1241. Curs acadèmic: 2016/2017A key point to the success of a game is the immersion that creates on the player through its environment, this refers to the playable levels and the soundtrack of the game [1]. Focusing on this matter is something very valuable for game makers. This Final Degree Project is about creating such engaging and explorable horror environment, as a demonstration of what can be done in a game without actually creating the whole game, but a demo. On this document, the demo will be referred to as a game. The main objective of this project is the creation of a complete and explorable 3D environment that creates tension and fear in whoever plays it. Specifically, it consists on a mountain which you are be able to explore and hear. It is set on night time, thus having the corresponding sounds of nocturnal animals and some added extras, that creates a tense atmosphere. This is entirely done on Unreal Engine

Reflexiones sobre la universidad nacional

Se presentan algunas reflexiones y comentarios con respecto a unas situaciones que he observado en la Universidad Nacional y que he tratado de analizar: Configuración en la sede de Santafé de Bogotá de tres instituciones desconectadas entre si, aumento de burocratización y papel de los Institutos Interfacultades en la Universidad. Enuncio unos principios fundamentales que deben caracterizar a una universidad.Some criticisms and analytical comments regarding specific facts at Universidad Nacional de Colombia are presented: three institutional entities at the University in Santafé de Bogotá with unrelated functions each other, an increased bureaucratic staff, the actual role of interfaculty institutes. Fundamental and basic characterization of the University are suggested and advocated

Comparación y detección de patrones de movimiento en video

Ingeniero (a) ElectrónicoPregrad

Influencia de arbustivas forrajeras nativas y diferentes fuentes amoniacales en el balance de nitrógeno de borregos

Tesis (Maestría en Ciencias Especialidad en Producción Animal) UANLUANLhttp://www.uanl.mx

La indeterminación normativa en el derecho tributario peruano a través de sus casos de lagunas y antinomias

Contrariamente a las perspectivas tradicionales que elaboran teorías y argumentos para sostener que el Derecho Tributario o bien no tiene lagunas jurídicas o que bien sí las tiene, nosotros hemos optado por una perspectiva distinta, que consiste en comprobar empíricamente mediante el análisis jurisprudencial, que el Tribunal Fiscal y del Tribunal Constitucional resuelven casos que inequívocamente califican como lagunas jurídicas y antinomias, aun cuando no lo digan formalmente e inclusive cuando lo nieguen expresamente, comprobando con ello que en el Derecho Tributario objetivamente existen supuestos de indeterminación normativa. Tradicionalmente se ha sostenido que en el Derecho Tributario no existen lagunas jurídicas, precisamente por ser completo a causa del principio de legalidad, reserva de ley y tipicidad, de los que se deriva una regla general excluyente o principio de cierre, que constituye derecho positivo y conforme al cual, lo no regulado no está fiscalmente gravado. Conforme a ello, cualquier caso relevante o bien tiene una regla específica que lo regula, o no la tiene. En este último caso, sería de aplicación la regla de cierre, que dispone la ausencia de gravamen. La tradicional reconstrucción del Derecho Tributario está elaborada sobre los caracteres del primigenio “Estado Legal de Derecho”, cuyas bases teóricas son las del positivismo teórico, que concebía al derecho como pleno, cerrado, autosuficiente y consistente; por ende, carente de lagunas y de antinomias. Sin embargo, desde poco antes de mediados del Siglo XX el modelo de estado ha evolucionado hacia el “Estado Constitucional de Derecho“ y sus bases teóricas también se han reformulado. Ahora se admite que la Constitución al igual que los principios tienen valor normativo. Hay control de la constitucionalidad de las leyes, lo que quiere decir que el legislador se puede equivocar. El principio de legalidad ha cedido su supremacía al principio de constitucionalidad. Se admite la incorporación de la moral al derecho, entre otros caracteres, conforme a los cuales, no hay objeción para admitir la existencia de lagunas en el Derecho Tributario, toda vez que las reglas son derrotables y los principios en conflicto se aplican por ponderación. Así por ejemplo, en la RTF 1479-10-2013 se da cuenta de un caso en el que se determinó incremento patrimonial no justificado, que constituye renta presunta, pero para el cual el sistema no contenía regla que fijara la alícuota que permita calcular el impuesto. Claramente es un caso de laguna normativa en el que no hay regla que establezca la tasa aplicable. Conforme a la reconstrucción del positivismo teórico, se debió haber resuelto que el supuesto no estaba gravado, en aplicación de la regla de cierre; sin embargo, el Tribunal Fiscal aplicando el principio nadie puede beneficiarse de su propia torpeza, resolvió disponiendo el gravamen y aplicando la escala progresiva acumulativa que está prevista para rentas de cuarta y quinta categoríaTesi