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The development of a new method to determine the presence of the organoarsenic additives p -arsanilic acid (ASA), roxarsone (ROX) and nitarsone (NIT) in livestock feeds by high performance liquid chromatography coupled to ultraviolet oxidation hydride generation atomic fluorescence spectrometry (HPLC-UV/HG-AFS) after microwave assisted extraction (MAE) was proposed. Chromatographic separation was achieved on a C18 column with 2% acetic acid/methanol (96:4, v/v) as the mobile phase. The limits of detection (LODs) were 0.13, 0.09 and 0.08 mg L −1 , and the limits of quantification (LOQs) were 0.44, 0.30 and 0.28 mg L −1 . The relative standard deviations (RSDs) for ASA, ROX and NIT determined from five measurements of the mixed calibration standard were 3.3, 5.3, and 5.4%, respectively. MAE extraction of phenylated arsenic compounds using 1.5 M H 3 PO 4 at 120 °C for 45 min allowed for maximum recoveries (%) of total arsenic (As) and organoarsenic species, with no degradation of these compounds. The extraction of total As was approximately 97%, and the As species recoveries were between 95.2 and 97.0%. The results of the analysis were validated using mass balance by comparing the sum of extracted As with the total concentration of As in the corresponding samples. The method was successfully applied to determine the presence of these compounds in feed samples. ASA was the only As species detected in chicken feed samples, with a concentration between 0.72 and 12.91 mg kg −1 .

Resumen. En el Servicio Medico Forense de la Procuraduria de Justicia del Estado de Nuevo Leon, se revisaron siete cadaveres y/o fragmentos de humanos, de los cuales se sospechaba la presencia de sustancias toxicas. Se realizaron estudios toxicologicos para rastrear psicotropicos, estupefacientes y alcohol etilico. Se recolectaron larvas de Cochliomya macellaria (Fabricius), Chrysomya rufifacies Macquart), Sarcophaga haemorrhoidalis (Fallen), y Musca domestica (Linnaeus). Se detecto cocaina en las larvas obtenidas de cuatro cadaveres, con excepcion del sarcofagido, por medio de un Cromatografo de Liquidos de Alta Resolucion.

The air PM2.5 concentration and its heavy metal content (Fe, Pb, Mn, Ni, As) were measured in the Metropolitan Area of Monterrey, Mexicoin Mexico, an area that is characterized by both very active and diverse industrial activity and intense highway traffic and industrial activity. The 24-h PM2.5 samples were collected in two different zones during a 1-year-long measurement program (February 2008–February 2009). The year PM2.5 average was above 15 μg/m3 exceeding Mexican and international standards. The difference of PM2.5 in each zone was not statistically significant. The greatest metal content was for iron, followed by lead, manganese, nickel and arsenic. The difference in metal content for Pb, Mn, and As was statistically significant.

La presente investigación se encuentra enmarcada dentro del paradigma interpretativo y el enfoque cualitativo, cuya finalidad es analizar e interpretar el uso de la retroactividad y su aplicabilidad como Sanción frente a la Injustificacion del Pago de la Cuota de Alimentos para menores por parte de los Obligados Legalmente en Colombia. La evasión injustificada de los obligados legalmente a dar alimentos Constituye, tanto en el marco jurídico nacional como en el internacional, una grave violación a los derechos de los niños, las niñas y los adolescentes, razón por la cual, categorías como la familia, la descendencia (menores de edad) y la obligación alimentaria dentro del núcleo familiar, son definidas, reguladas y protegidas por instrumentos normativos. Por ello, no requiere que exista causación efectiva de un daño al bien jurídico protegido de ejecución continuada, pues atentación contra la norma persiste hasta tanto se dé cumplimiento a la obligación. Por su parte la Corte Constitucional, Corte Suprema de Justicia y el Consejo de Estado mencionan que la obligación alimentaria está fundamentada en el principio de solidaridad, según el cual los miembros de la familia tienen la obligación de suministrar la subsistencia a aquellos integrantes de la misma que no están en capacidad de asegurársela por sí mismos. En Colombia la retroactividad se constituye como una herramienta cuya finalidad es la de brindar mayores garantías a los derechos de las personas ante ciertas situaciones anteriores a la promulgación de la ley que se encuentra rigiendo en el momento de sus acontecimientos, siempre y cuando el legislador lo contemple así. Es decir, su implementación se debe dar en beneficio del derecho de alimentos de menores, será complementaria para su protección integral y el disfrute de este derecho, así como la reducción de la evasión, coadyuvando a su adecuado sostenimiento y a su desarrollo integral.

Cr

Cr3+-doped TiO2 nanoparticles (Ti-Cr) were synthesized by microwave-assisted sol-gel method. The Ti-Cr catalyst was characterized by X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, N2 adsorption-desorption analysis, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and zetametry. The anatase mesoporous Ti-Cr material exhibited a specific surface area of 54.5 m2/g. XPS analysis confirmed the proper substitution of Ti4+ cations by Cr3+ cations in the TiO2 matrix. The particle size was of average size of 17 nm for the undoped TiO2 but only 9.5 nm for Ti-Cr. The Cr atoms promoted the formation of hydroxyl radicals and modified the surface adsorptive properties of TiO2 due to the increase in surface acidity of the material. The photocatalytic evaluation demonstrated that the Ti-Cr catalyst completely degraded (4-chloro-2-methylphenoxy) acetic acid under visible light irradiation, while undoped TiO2 and P25 allowed 45.7% and 31.1%, respectively. The rate of degradation remained 52% after three cycles of catalyst reuse. The higher visible light photocatalytic activity of Ti-Cr was attributed to the beneficial effect of Cr3+ ions on the TiO2 surface creating defects within the TiO2 crystal lattice, which can act as charge-trapping sites, reducing the electron−hole recombination process.

En este documento se estudia el problema de la vivienda de interés social, VIS, en Bogotá asociada al precio del suelo. Se revisan algunos postulados que han tenido un impacto sobre el problema de manejo del precio del suelo. Se parte de la revisión de la estructura de asentamiento poblacional de la ciudad como evidencia de la desequilibrada ocupación y oferta de bienes urbanos. La perspectiva cuantitativa utilizada indica que la incorporación de suelo urbano no tiene el efecto señalado de bajar los precios. La dinámica de los precios del suelo muestra un comportamiento inercial de estos, derivados de la racionalidad algo ingenua de los propietarios. La asociación con la evolución de la construcción indica que los constructores y su tendencia a capturar rentas de anticipación los lleva a cometer errores si no se preveen los ciclos. A pesar de ser una industria con una organización competitiva existe evidencia de un componente no explicado del precio que puede ser igualmente una renta, en este caso tecnológica. This document analyzes the issue of social interest housing in Bogotá related with land prices. Additionally, some postulates that have had an impact over land pricing issues have been reviewed. As a starting point it has been reviewed the population settlement structure in the city as an evidence of the unbalanced occupation and offer of property. The quantitative perspective used shows that the incorporation of urban land does not have the aforementioned effect of lowering prices. The dynamic of land prices shows an inertial behavior of such, derived from the somehow naïve rationality of the owners. The association with the construction evolution shows the tendency of constructors to capture rent anticipation, leads them to make mistakes if cycles are not foreseen. Although being an industry with a competitive organization, there is evidence of a non explained element of pricing that may be a rent, in this case a technological one.

Convenio de Asociacion 244 de 2014 entre la Universidad Sergio Arboleda y el Departamento Administrativo del Deporte, la Recreacion, la Actividad Fisica y el Aprovechamiento del Tiempo Libre - Coldeportes En este libro se presentan los principales resultados de la ejecucion del proyecto de investigacion en el marco del Convenio 244 de 2014 entre Coldeportes y la Universidad Sergio Arboleda. La pretension de este libro resultado de investigacion es sintetizar los principales insumos que permitiran, a los tomadores de decision y a los actores que componen el Sistema Nacional del Deporte, llevar a cabo el proceso de agendamiento, formulacion o reformulacion de la politica publica del deporte en Colombia.

Full and unambiguous assignment of all 1H- and 13C-NMR resonances of the isomers due to restricted C-N amide bond rotation of N-formyl-o-toluidine and N,N'-bis-formyl-o-tolidine in DMSO-d6 is reported. The cis-isomer predominates in the equilibrium mixture of both compounds as 1D-NOE difference experiments show.

In this work, nitrogen-doped ZnO material was synthesized by the sol-gel method using zinc acetate as the precursor and urea as the nitrogen source (15, 20, 25 and 30% wt.). For comparative purposes, bare ZnO was also prepared. The influence of N doping on structural, morphological, optical and photocatalytic properties was investigated. The synthesized catalysts were characterized by XRD, SEM-EDS, diffuse reflectance UV-Vis spectroscopy, BET and XPS analysis. The photocatalytic activity of N-doped ZnO catalysts was evaluated during the degradation of a mixture of herbicides (2,4-D and picloram) under visible radiation ≥400 nm. The photo-absorption wavelength range of the N-doped ZnO samples was shifted to longer wavelength compared to those of the unmodified ZnO. Among different amounts of dopant agent, the 30% N-doped ZnO material showed higher visible-light activity compared with pure ZnO. Several degradation by-products were identified by using HPLC and ESI-MS/MS. The enhancement of visible photocatalytic activity of the N-doped ZnO semiconductor could be mainly due to their capability in reducing the electron-hole pair recombination.

In this study, a multisyringe chromatography system (MSC) using a C18 monolithic column was proposed for the on-line monitoring of the photocatalytic degradation of isoniazid (INH, 10 mg L −1 ) and pyrazinamide (PYRA, 5 mg L −1 ) mixtures in aqueous solution using a small sample volume (200 μL) with an on-line filtration device in a fully automated approach. During the photocatalytic oxidation using TiO 2 or ZnO semiconductor materials, total organic carbon (TOC) and the formed intermediates were analyzed off-line using ion chromatography, ion exclusion HPLC, and ESI-MS/MS. The results showed that TiO 2 exhibits a better photocatalytic activity than ZnO under UV irradiation (365 nm) for the degradation of INH and PYRA mixtures, generating 97% and 92% degradation, respectively. The optimal oxidation conditions were identified as pH 7 and 1.0 g L −1 of TiO 2 as catalyst. The mineralization of the initial organic compounds was confirmed by the regular decrease in TOC, which indicated 63% mineralization, and the quantitative release of nitrate and nitrite ions, which represent 33% of the nitrogen in these compounds. The major intermediates of INH degradation included isonicotinamide, isonicotinic acid, and pyridine, while the ESI-MS/MS analysis of PYRA aqueous solution after photocatalytic treatment showed the formation of pyrazin-2-ylmethanol, pyrazin-2-ol, and pyrazine. Three low-molecular weight compounds, acetamide, acetic acid and formic acid, were detected during INH and PYRA decomposition. PYRA was more resistant to photocatalytic degradation due to the presence of the pyrazine ring, which provides greater stability against OH attack.

Resumen Introducción. El efecto colateral del "progreso" irresponsable ha traído como consecuencia un aumento en la concentración de los gases de efecto invernadero (GEI), los cuales tienen diferente contribución al cambio climático en función de su concentración en la atmósfera y su potencial de calentamiento global. La Convención Marco de Naciones Unidas sobre el Cambio Climático, realizada en 1992, fue la base para las negociaciones que se plasmaron en el Protocolo de Kioto en el año 1997. Este Protocolo se basa en una premisa fundamental: reconocer responsabilidades compartidas pero diferenciadas, en donde los países industrializados, que son los grandes generadores de GEI y responsables mayoritarios del calentamiento global, sean también los principales responsables de remediar esta situación. Objetivo. Fortalecer la penetración de los proyectos de MDL, aprovechando las oportunidades que ofrece el consolidado mercado regulado del carbono. Metodología. Se expone un marco conceptual del cambio climático y se compilan las bases normativas y técnicas del MDL. El estudio, además, contempla una revisión del estado del arte del MDL en Colombia, contextualizando esta realidad con otros países de la región, y se presentan proyecciones del mercado regulado para el desarrollo de estos proyectos. Resultados. Considerando el potencial geográfico e industrial de Colombia, la reducción de GEI (en última instancia CER generados) está muy por debajo de las expectativas de una nación con fuertes sectores agroindustriales, mineros y energéticos, todos sectores de alta generación de GEI. Por tanto, existe un potencial no aprovechado por el país. Conclusiones. Colombia está por debajo de su potencialidad de penetración de proyectos de Mecanismo de Desarrollo Limpio debido principalmente a i) Desconocimiento de los tomadores de decisiones de las oportunidades del mercado del carbono, principalmente por falta de difusión y capacitación, ii) Altos precios asociados a la elaboración e implementación de este tipo de proyectos, y iii) Falta de instrumentos de financiación para desarrollar proyectos sostenibles. Abstract Introduction. The collateral effect of irresponsible "progress" has brought as a consequence an increase of the greenhouse gases (GHG), which contribute in several ways to climate change given their concentrations in the atmosphere and their potential of global warming. The United Nations Framework Convention on Climate Change, celebrated in 1992, was the base for the negotiations contained by the Kyoto Protocol in 1997. This protocol is based on a fundamental premise: To recognize shared but differentiated responsibilities in which industrialized nations, which generate most of the GHG and are thus the ones with the main responsibility of global warming, must also lead the solution of the situation. Objective. To strengthen the Clean Development Mechanisms (CDM) projects, harnessing the opportunities offered by the consolidation of the regulated market of carbon. Methodology. A conceptual framework of the climate change is exposed and the regulatory and technical bases of CDM are compiled. The study, also, includes a revision of CDM´s state of the art in Colombia, providing a context of this reality with other countries from the region, and introduces projections of the regulated market in order to foresee strategies for their strengthening, their penetration and their divulgation among the Colombian sectors. Results. Considering Colombia´s geographical and industrial potential, the greenhouse gases reduction (finally CER generated) is way below the expectations of a country with strong agricultural and livestock, mining and energy sectors, which are all great greenhouse gases generators. There is, therefore, a potential not exploited by the country. Conclusions. Colombia is below its potential for the penetration of CDM projects, mainly due to: i) Lack of knowledge of decision makers about the opportunities carbon market has, especially because of a lack of information and training, ii) High prices associated to the elaboration and implementation of this type of projects and iii), Lack of financial instruments to develop sustainable projects. Resumo Introdução. O efeito colateral do "progresso" irresponsável trouxe como consequência um aumento na concentração dos gases de efeito estufa (GEI), os quais têm diferente contribuição à mudança climática em função de sua concentração na atmosfera e seu potencial de aquecimento global. A Convenção Marco de Nações Unidas sobre a Mudança Climática, realizada em 1992, foi a base para as negociações que se plasmaram no Protocolo de Kioto no ano 1997. Este Protocolo se baseia numa premissa fundamental: reconhecer responsabilidades compartilhadas mas diferenciadas, em onde os países industrializados, que são os grandes geradores de GEI e responsáveis maioritários do aquecimento global, devem ser também os principais responsáveis de remediar esta situação. Objetivo. Fortalecer a penetração dos projetos de MDL, aproveitando as oportunidades que oferece o consolidado mercado regulado do carbono. Metodologia. Se expõe um marco conceitual da mudança climática e se compilam as bases normativas e técnicas do MDL. O estudo ademais contempla uma revisão do estado da arte do MDL na Colômbia, contextualizando esta realidade com outros países da região, e se apresentam projeções do mercado regulado para o desenvolvimento destes projetos.Resultados.Os achados permitem elaborar os fundamentos para o progresso de estratégias de fortalecimento, penetração e difusão nos diferentes setores colombianos. Resultados. Considerando o potencial geográfico e industrial da Colômbia, a redução de GEI (em última instância CER gerados) está muito por embaixo das expectativas de uma nação com fortes setores agroindustriais, mineiros e energéticos, todos setores de alta geração de GEI. Por tanto existe um potencial não aproveitado pelo país. Conclusões. A Colômbia está por embaixo de sua potencialidade de penetração de projetos de Mecanismo de Desenvolvimento Limpo devido principalmente a: i) Desconhecimento dos tomadores de decisões das oportunidades do mercado do carbono, principalmente por falta de difusão e capacitação, ii) Altos preços associados à elaboração e implementação deste tipo de projetos, e iii) Falta de instrumentos de financiamento para desenvolver projetos sustentáveis.

Chrysomya rufifacies (Macquart) is widely known as a colonizer on corpses. In the state of Nuevo Leon, Mexico, it has been usually found as part of the cadaveric fauna of human corpses, in “necro” traps with pigs, and in bottle traps with carrion. In the archives of the Attorney General of the State of Nuevo Leon, there is abundant evidence that criminals have used organophosphate and carbamate insecticides to poison persons and cause death. The trial was conducted at the Facultad de Ciencias Biologicas of Universidad Autonoma de Nuevo Leon and Instituto de Criminalistica y Servicios Periciales …

Magíster en Economía del Medio Ambiente y los Recursos Naturales Maestría

Peroxisomicine A1 (PA1) is a dimeric hydroxyanthracenone isolated from fruits of plants belonging to the genus Karwinskia. Showing selective toxicity between malignant and benign cell lines, it is currently under screening as an antineoplastic agent. Very little is known about its mechanism of action. In the present work the extent of binding of this substance with Bovine Serum Albumin (BSA) and Human Serum Albumin (HSA) at pH 7.2 and 7.4 has been evaluated using the spectrophotometric method. Absorbance of PA1 was altered by the presence of albumin and this property was used to generate binding isotherms. The investigation was carried out at four different temperatures. The data were analyzed by assuming two types of binding sites. Results indicated that PA1 binds to both albumins at physiological pH, which is reflected by the affinity constants of the order of 105. There are two types of binding sites in the albumin for PA1; with the electrostatic forces being discarded, the hydrophobic and hydrogen bond are more probable. Binding with HSA is stronger than with BSA.