Application of biogas slurries from energy crops to arable soils and their impact on carbon and nitrogen dynamics

The use of renewable primary products as co-substrate or single substrate for biogas production has increased consistently over the last few years. Maize silage is the preferential energy crop used for fermentation due to its high methane (CH4) yield per hectare. Equally, the by-product, namely biogas slurry (BS), is used with increasing frequency as organic fertilizer to return nutrients to the soil and to maintain or increase the organic matter stocks and soil fertility. Studies concerning the application of energy crop-derived BS on the carbon (C) and nitrogen (N) mineralization dynamics are scarce. Thus, this thesis focused on the following objectives: I) The determination of the effects caused by rainfall patterns on the C and N dynamics from two contrasting organic fertilizers, namely BS from maize silage and composted cattle manure (CM), by monitoring emissions of nitrous oxide (N2O), carbon dioxide (CO2) and CH4 as well as leaching losses of C and N. II) The investigation of the impact of differences in soil moisture content after the application of BS and temperature on gaseous emissions (CO2, N2O and CH4) and leaching of C and N compounds. III) A comparison of BS properties obtained from biogas plants with different substrate inputs and operating parameters and their effect on C and N dynamics after application to differently textured soils with varying application rates and water contents. For the objectives I) and II) two experiments (experiment I and II) using undisturbed soil cores of a Haplic Luvisol were carried out. Objective III) was studied on a third experiment (experiment III) with disturbed soil samples. During experiment I three rainfall patterns were implemented including constant irrigation, continuous irrigation with periodic heavy rainfall events, and partial drying with rewetting periods. Biogas slurry and CM were applied at a rate of 100 kg N ha-1. During experiment II constant irrigation and an irrigation pattern with partial drying with rewetting periods were carried out at 13.5°C and 23.5°C. The application of BS took place either directly before a rewetting period or one week after the rewetting period stopped. Experiment III included two soils of different texture which were mixed with ten BS’s originating from ten different biogas plants. Treatments included low, medium and high BS-N application rates and water contents ranging from 50% to 100% of water holding capacity (WHC). Experiment I and II showed that after the application of BS cumulative N2O emissions were 4 times (162 mg N2O-N m-2) higher compared to the application of CM caused by a higher content of mineral N (Nmin) in the form of ammonium (NH4+) in the BS. The cumulative emissions of CO2, however, were on the same level for both fertilizers indicating similar amounts of readily available C after composting and fermentation of organic material. Leaching losses occurred predominantly in the mineral form of nitrate (NO3-) and were higher in BS amended soils (9 mg NO3--N m-2) compared to CM amended soils (5 mg NO3--N m-2). The rainfall pattern in experiment I and II merely affected the temporal production of C and N emissions resulting in reduced CO2 and enhanced N2O emissions during stronger irrigation events, but showed no effect on the cumulative emissions. Overall, a significant increase of CH4 consumption under inconstant irrigation was found. The time of fertilization had no effect on the overall C and N dynamics. Increasing temperature from 13.5°C to 23.5°C enhanced the CO2 and N2O emissions by a factor of 1.7 and 3.7, respectively. Due to the increased microbial activity with increasing temperature soil respiration was enhanced. This led to decreasing oxygen (O2) contents which in turn promoted denitrification in soil due to the extension of anaerobic microsites. Leaching losses of NO3- were also significantly affected by increasing temperature whereas the consumption of CH4 was not affected. The third experiment showed that the input materials of biogas plants affected the properties of the resulting BS. In particular the contents of DM and NH4+ were determined by the amount of added plant biomass and excrement-based biomass, respectively. Correlations between BS properties and CO2 or N2O emissions were not detected. Solely the ammonia (NH3) emissions showed a positive correlation with NH4+ content in BS as well as a negative correlation with the total C (Ct) content. The BS-N application rates affected the relative CO2 emissions (% of C supplied with BS) when applied to silty soil as well as the relative N2O emissions (% of N supplied with BS) when applied to sandy soil. The impacts on the C and N dynamics induced by BS application were exceeded by the differences induced by soil texture. Presumably, due to the higher clay content in silty soils, organic matter was stabilized by organo-mineral interactions and NH4+ was adsorbed at the cation exchange sites. Different water contents induced highest CO2 emissions and therefore optimal conditions for microbial activity at 75% of WHC in both soils. Cumulative nitrification was also highest at 75% and 50% of WHC whereas the relative N2O emissions increased with water content and showed higher N2O losses in sandy soils. In summary it can be stated that the findings of the present thesis confirmed the high fertilizer value of BS’s, caused by high concentrations of NH4+ and labile organic compounds such as readily available carbon. These attributes of BS’s are to a great extent independent of the input materials of biogas plants. However, considerably gaseous and leaching losses of N may occur especially at high moisture contents. The emissions of N2O after field application corresponded with those of animal slurries.

Climate change and hunger as the challenges in the global food system

In the last decades, there has been a growing tendency towards international trade and globalisation, particularly leading to a significant increase in flows of agricultural commodities worldwide. From a macroeconomic perspective, the commodity projections are more optimistic than the previous years and the long run tendency shows an increasing demand for feedstock. However, the strong shifts of shocks and fluctuations (in terms of prices and volumes) are a concern to global food security, with the number of hungry people rising to nearly one billion. Agriculture is a main user of natural resources, and it has a strong link with rural societies and the environment. Forecasted impacts from climate change, limited productive endorsements and emerging rivals on crop production, such bio-energy, aggravate the panorama on food scarcity. In this context, it is a great challenge on farming and food systems to reduce global hunger and produce in sustainable ways adequate supplies for food, feed, and non-food uses. The main objective of this work is to question the sustainability of food and agriculture systems. It is particularly interesting to know its role and if it will be able to respond to a growing population with increasing food demand in a world where pressure on land, water and other natural resources are already evident, and, moreover, climate change will also condition and impact the outcome. Furthermore, a deeper focus will be set on developing countries, which are expected to emerge and take a leading role in the international arena. This short paper is structured as follows: Section I, “Introduction”, describes the social situation regarding hunger, Section II, “Global Context”, attempts to summarise the current scenario in the international trading scheme and present the emerging rivals for primary resources, and in Section III, “Climate Change”, presents an overview of possible changes in the sector and future perspectives in the field. Finally, in Section IV, “Conclusion”, the main conclusions are presented.

Water Resource Pollution and Impacts on the local livelihood: A case study of Beas River in Kullu District, India

The rivers are considered as the life line of any country since they make water available for our domestic, industrial and recreational functions. The quality of river water signifies the health status and hygienic aspects of a particular region, but the quality of these life lines is continuously deteriorating due to discharge of sewage, garbage and industrial effluents into them. Thrust on water demand has increased manifolds due to the increased population, therefore tangible efforts to make the water sources free from pollution is catching attention all across the globe. This paper attempts to highlight the trends in water quality change of River Beas, right from Manali to Larji in India. This is an important river in the state of Himachal Pradesh and caters to the need of water for Manali and Kullu townships, besides other surrounding rural areas. The Manali-Larji Beas river stretch is exposed to the flow of sewage, garbage and muck resulting from various project activities, thereby making it vulnerable to pollution. In addition, the influx of thousands of tourists to these towns also contributes to the pollution load by their recreational and other tourist related activities. Pollution of this river has ultimately affected the livelihood of local population in this region. Hence, water quality monitoring was carried out for the said stretch between January, 2010 and January, 2012 at 15 various locations on quarterly basis, right from the upstream of Manali town and up to downstream of Larji dam. Temperature, color, odor, D.O. , pH, BOD, TSS, TC and FC has been the parameters that were studied. This study gives the broad idea about the characteristics of water at locations in the said river stretch, and suggestions for improving water quality and livelihood of local population in this particular domain.

The prediction of seasonal and inter-annual climate variations and their impacts on the water resources in the eastern seaboard of Thailand

The research of this thesis dissertation covers developments and applications of short-and long-term climate predictions. The short-term prediction emphasizes monthly and seasonal climate, i.e. forecasting from up to the next month over a season to up to a year or so. The long-term predictions pertain to the analysis of inter-annual- and decadal climate variations over the whole 21st century. These two climate prediction methods are validated and applied in the study area, namely, Khlong Yai (KY) water basin located in the eastern seaboard of Thailand which is a major industrial zone of the country and which has been suffering from severe drought and water shortage in recent years. Since water resources are essential for the further industrial development in this region, a thorough analysis of the potential climate change with its subsequent impact on the water supply in the area is at the heart of this thesis research. The short-term forecast of the next-season climate, such as temperatures and rainfall, offers a potential general guideline for water management and reservoir operation. To that avail, statistical models based on autoregressive techniques, i.e., AR-, ARIMA- and ARIMAex-, which includes additional external regressors, and multiple linear regression- (MLR) models, are developed and applied in the study region. Teleconnections between ocean states and the local climate are investigated and used as extra external predictors in the ARIMAex- and the MLR-model and shown to enhance the accuracy of the short-term predictions significantly. However, as the ocean state – local climate teleconnective relationships provide only a one- to four-month ahead lead time, the ocean state indices can support only a one-season-ahead forecast. Hence, GCM- climate predictors are also suggested as an additional predictor-set for a more reliable and somewhat longer short-term forecast. For the preparation of “pre-warning” information for up-coming possible future climate change with potential adverse hydrological impacts in the study region, the long-term climate prediction methodology is applied. The latter is based on the downscaling of climate predictions from several single- and multi-domain GCMs, using the two well-known downscaling methods SDSM and LARS-WG and a newly developed MLR-downscaling technique that allows the incorporation of a multitude of monthly or daily climate predictors from one- or several (multi-domain) parent GCMs. The numerous downscaling experiments indicate that the MLR- method is more accurate than SDSM and LARS-WG in predicting the recent past 20th-century (1971-2000) long-term monthly climate in the region. The MLR-model is, consequently, then employed to downscale 21st-century GCM- climate predictions under SRES-scenarios A1B, A2 and B1. However, since the hydrological watershed model requires daily-scale climate input data, a new stochastic daily climate generator is developed to rescale monthly observed or predicted climate series to daily series, while adhering to the statistical and geospatial distributional attributes of observed (past) daily climate series in the calibration phase. Employing this daily climate generator, 30 realizations of future daily climate series from downscaled monthly GCM-climate predictor sets are produced and used as input in the SWAT- distributed watershed model, to simulate future streamflow and other hydrological water budget components in the study region in a multi-realization manner. In addition to a general examination of the future changes of the hydrological regime in the KY-basin, potential future changes of the water budgets of three main reservoirs in the basin are analysed, as these are a major source of water supply in the study region. The results of the long-term 21st-century downscaled climate predictions provide evidence that, compared with the past 20th-reference period, the future climate in the study area will be more extreme, particularly, for SRES A1B. Thus, the temperatures will be higher and exhibit larger fluctuations. Although the future intensity of the rainfall is nearly constant, its spatial distribution across the region is partially changing. There is further evidence that the sequential rainfall occurrence will be decreased, so that short periods of high intensities will be followed by longer dry spells. This change in the sequential rainfall pattern will also lead to seasonal reductions of the streamflow and seasonal changes (decreases) of the water storage in the reservoirs. In any case, these predicted future climate changes with their hydrological impacts should encourage water planner and policy makers to develop adaptation strategies to properly handle the future water supply in this area, following the guidelines suggested in this study.

Thermal Impacts on Building Integrated Photovoltaic (BIPV) (Electrical, Thermal and Mechanical Characteristics)

Ein Drittel des weltweiten gesamten Energiebedarfs wird durch Gebäude verbraucht. Um diesen Energiebedarf teilweise zu decken, den erheblichen Energieverbrauch zu reduzieren und weiterhin andere Gebäudefunktionen beizubehalten, ist Gebäudeintegrierte Photovoltaik (BIPV) eine der am besten geeigneten Lösungen für die Gebäudenanwendung. Im Bezug auf eine Vielzahl von Gestalltungsmöglichkeiten, sind die Randbedingungen der BIPV-Anwendungen eindeutig anders im Vergleich zu Standard-PV-Anwendungen, insbesondere bezüglich der Betriebstemperatur. Bisher gab es nicht viele Informationen zu den relevanten thermischen Auswirkungen auf die entsprechenden elektrischen Eigenschaften zusammen mit thermischen und mechanischen relevanten Gebäudenfunktionen. Die meisten Hersteller übernehmen diese Eigenschaften von entsprechenden PV-Modulen und konventionellen Bauprodukten Normen, die zur ungenauen System- und Gebäudeplanungen führen. Deshalb ist die Untersuchung des thermischen Einflusses auf elektrische, thermische sowie mechanische Eigenschaften das Hauptziel der vorliegenden Arbeit. Zunächst wird das Temperatur-Model mit dem Power-Balance-Konzept erstellt. Unter Berücksichtigung der variablen Installationsmöglichkeiten und Konfigurationen des Moduls wird das Model auf Basis dynamischer und stationär Eigenschaften entwickelt. Im Hinblick auf die dynamische Simulation können der Energieertrag und Leistung zusammen mit der thermischen Gebäudesimulation in Echtzeit simuliert werden. Für stationäre Simulationen können die relevanten Gebäudefunktionen von BIPV-Modulen sowohl im Sommer als auch im Winter simuliert werden. Basierend auf unterschiedlichen thermischen und mechanischen Last-Szenarien wurde darüber hinaus das mechanische Model zusammen mit Variationen von Belastungsdauer, Montagesystem und Verkapselungsmaterialien entwickelt. Um die Temperatur- und Mechanik-Modelle zu validieren, wurden die verschiedenen Prüfeinrichtungen zusammen mit neuen Testmethoden entwickelt. Bei Verwendung der Prüfanlage „PV variable mounting system“ und „mechanical testing equipment“ werden zudem die verschiedenen Szenarien von Montagesystemen, Modul-Konfigurationen und mechanischen Belastungen emuliert. Mit der neuen Testmethode „back-bias current concept“ können zum einen die solare Einstrahlung und bestimmte Betriebstemperaturen eingestellt werden. Darüber hinaus wurden mit den eingangs erwähnten validierten Modellen das jeweilige elektrische, thermische und mechanische Verhalten auf andere Konfigurationen bewertet. Zum Abschluss wird die Anwendung von Software-Tools bei PV-Herstellern im Hinblick auf die entsprechenden Modellentwicklungen thematisiert.

Factores de riesgo de caídas intrahospitalarias en pacientes de 65 años o mayores en la Fundación Cardioinfantil

Las caídas intrahospitalarias son un problema permanente que cada vez toma mayor importancia en los servicios de hospitalización de las instituciones de cuidado agudo, sin embargo no hay claridad sobre los factores de riesgo más importantes modificables ya que la mayoría de las escalas de medición y conductas de prevención son extrapoladas de los estudios realizados en instituciones de cuidado crónico. El problema cobra mayor importancia en esta época ya que su incidencia impacta en forma negativa los indicadores de calidad de una institución y genera discapacidad y muerte. Materiales y métodos: Es un estudio de casos y controles basado en los registros de caída y en las historias clínicas de una institución de cuidado agudo La Fundación Cardioinfantil – Instituto de Cardiología en Bogotá (Colombia). Se evaluaron las Historias clínicas y registros del comité de caídas intrahospitalarias de 479 pacientes 245 casos y 234 controles desde enero de 2002 a julio de 2010. Resultados: Se evaluaron 60 variables y se realizo una caracterización descriptiva del mecanismo de caída y las consecuencias de la caída. Se obtuvo como resultado 16 variables con OR significativos estadísticamente, de las cuales solo 6 terminaron la regresión logística con gran significancia estadística (p= menor 0.001), dentro de las cuales se destacan: Discapacidad, Diagnostico cardiovascular y delirium. Conclusiones: Existen factores de riesgo posiblemente modificables en instituciones de cuidado agudo entre los cuales hay comunes con centros de cuidado crónico y otros propios de hospitales entrenados para la atención del paciente agudo. Palabras clave: Caidas. Hospital. Lesiones. Factores de riesgo, casos y conttroles

Desarrollo de un nuevo protocolo de cirugía general, que disminuya las devoluciones de medicamentos e insumos al almacén de cirugía del Hospital Méderi

Esta tesis surge como una oportunidad de mejora en el almacén de cirugías del Hospital MÉDERI, debido a la recurrente devolución de medicamentos e insumos solicitados por las auxiliares de enfermería para las cirugías generales, lo cual repercute directamente en pérdidas de productividad laboral por los re-procesos, un aumento en los errores humanos y posibles pérdidas de medicamentos e insumos. Tras esta clara oportunidad de mejora, se toma la decisión de evaluar el proceso interno del almacén de cirugías con el fin de conocer el punto crítico que genera esta situación; dando como resultado los protocolos de cirugías, los cuales al haber sido diseñados varios años atrás basados en una demanda presentada en ese momento, no están acorde con la realidad que se vive actualmente el almacén de cirugía. Por lo tanto se decidió implementar un pronóstico de promedio móvil, para identificar la demanda real que se presentan en el Hospital MÉDERI, esto seguido de una identificación gráfica comparativa que permitiera definir el nuevo protocolo de cirugía general, lo cual permite disminuir la cantidad de material solicitado, con lo cual se generan disminuciones significativas en el inventario, perdidas y un aumento en la productividad.

Factores de riesgo para convulsiones tras cirugía cardiaca con acido tranexamico: estudio de casos y controles, FCI

La cirugía cardiaca con circulación extracorpórea tiene riesgo de lesión del sistema nervioso central que impacta negativamente el desenlace postoperatorio. Su espectro es variable siendo lo más frecuente la lesión isquémica. Sin embargo esta no es la única complicación neurológica, las convulsiones también tienen un impacto significativo sobre la morbimortalidad y se asocian a un incremento de la estancia hospitalaria. Mientras que los eventos isquémicos tras cirugía cardiaca están bien caracterizados, existen pocos datos acerca de las convulsiones postoperatorias de origen no isquémico. Dentro de las teorías postuladas para explicar estos fenómenos llama la atención el potencial epileptogénico de los medicamentos antifibrinolíticos, ampliamente utilizados con el objetivo de minimizar el sangrado y reducir la exposición a hemoderivados. Numerosos reportes sugieren que el ácido tranexámico puede inducir actividad convulsiva en el postoperatorio. El objetivo de este estudio retrospectivo de casos y controles fue examinar los factores asociados con convulsiones postoperatorias en pacientes sometidos a cirugía cardiaca con circulación extracorpórea que recibieron ácido tranexámico. Todos los pacientes sometidos a cirugía cardiaca con circulación extracorpórea entre Enero de 2008 y Diciembre de 2009 fueron identificados. Los casos se definieron como aquellos pacientes que convulsionaron y requirieron inicio de anticonvulsivantes dentro de las 48 horas post-quirúrgicas. Los criterios de exclusión incluyeron epilepsia preexistente y pacientes con alguna lesión isquémica nueva en neuroimágen. Los controles fueron seleccionados aleatoriamente a partir de la cohorte inicial. Se analizaron un total de 28 casos y 112 controles. Se evidenció una asociación entre disfunción renal, valores elevados de creatinina preoperatoria y convulsiones postoperatorias.

Análisis del rol de las empresas militares y de seguridad privada. Estudio de caso: Guerra en Irak 2003-2010

Las Empresas Militares y de Seguridad Privada (EMSP) se han caracterizado por prestar diferentes tipos de servicios en distintos escenarios internacionales y nacionales. Asimismo, por ofrecer una amplia gama de actividades que han sido útiles para quienes solicitan de ellas. En el caso especifico de la Guerra en Irak fue relevante debido a que el gobierno decidió contratar varias compañías que además de contar con cientos de empleados, llevaron a cabo funciones que antes habían sido efectuadas únicamente por las fuerzas militares o por empleados oficiales del gobierno estadounidense. De esta forma, por medio del presente estudio de caso se buscan analizar las tareas que fueron asignadas, dar a conocer datos referentes al número de contratistas en Irak, el valor de algunos contratos, las funciones que fueron cedidas a estas compañías, como también ver de qué modo afectó positiva o negativamente al gobierno de los Estados Unidos. No obstante, el estudio del caso de Irak dio la posibilidad de indagar acerca del cómo los Estados podrían utilizar de mejor forma los servicios de las EMSP sin perder el control o crear dependencia de estas.

Parada de seguridad: impacto en la cultura de seguridad del equipo quirúrgico de una institución de alta complejidad

Introducción: Las instituciones de Salud dentro de sus objetivos de servicio de alta calidad para los pacientes, deben considerar diversas estrategias que promuevan su Seguridad durante todo el proceso de atención; herramientas como la “Parada de Seguridad” promueven la seguridad en el proceso de atención quirúrgica. El uso de esta estrategia por parte de los profesionales de salud, debe ser promovido y evaluado continuamente para reforzar la Cultura de Seguridad, lo cual impacta de manera transversal la atención del usuario. Objetivo: Determinar el impacto de la implementación de la Parada de Seguridad sobre la calificación de Cultura de Seguridad en las salas de cirugía de una Institución acreditada de IV nivel en Bogotá. Metodología: Se realizó un estudio de intervención para la medición y comparación de la Calificación de la Encuesta de Cultura de Seguridad, antes y después de la aplicación de la Parada de Seguridad en las salas de cirugía en la Institución de estudio. Resultados: La encuesta obtuvo un puntaje global de 66.1% en la primera medición y 64% después de la intervención (p<0.001), se encontró diferencia significativa entre la primera y segunda medición. El análisis según las dimensiones de la encuesta y especialidad/área de trabajo, no evidenció diferencias significativas. Conclusiones: La implementación de estrategias orientadas a fortalecer la Seguridad del Paciente, modifican la percepción de Seguridad de los profesionales de Salud en los procesos de atención. Se deben realizar intervenciones y mediciones con mayor frecuencia para obtener resultados satisfactorios a largo plazo.

Rearrangement of the urban space in the sector of Saint Victorino and Saint Ines (Bogota) in relation with the dynamics of informality and marginality (1948-2010)

The present article analyze the urban transformations happened in the sector of Saint Victorino and Saint Ines in the city of Bogota D.C. between 1948 and 2010, making use of the "Genealogical Methodology" during the process of inquiry that allow to contrast the visions that are usually accepted of "progress" and "urban renovation" in the urban market context by the existence of a informal economic and a population in conditions of marginality that configures a good part of the "popular urban culture" of the Bogota in the 20th and 21st century. This vision permit to observe from various perspectives the changes that happened in this sector of the city, the impacts of the history facts occurred en this time period and, in special, the real effects of a rearrangement urban process that began in 1998 and has been prolonged to date, which has left a significant mark about the urban and social physiognomy of the place.

¿Impactó el programa de Tutores Pares a sus tutores?

Introducción: El programa de Tutores Pares-TP es una iniciativa creada en la EMCS de la Universidad del Rosario que brinda acompañamiento académico a través de estudiantes-tutores a pares menos avanzados. Éste entrega a sus Tutores sistemáticamente, herramientas para desempeñarse armónicamente en el ejercicio de guía y provee habilidades para el manejo del saber. Este estudio busca explorar posibles ´impactos´ generados tras la participación de estudiantes de medicina como TPs dentro de un programa estructurado. Materiales y métodos: Estudio cualitativo que involucró la construcción y aplicación de encuestas a grupos focales –TPs, Docentes y Familiares- creadas a partir de seis ejes/categorías que enmarcan al médico ideal. Las respuestas obtenidas de preguntas cerradas –en escala valorativa- y de naturaleza abierta fueron sometidas a análisis descriptivo –modas- y triangulación. Resultados: 41 tutores, agrupados en 4 grupos de análisis, evidenciaron un impacto general positivo con predominio en habilidades interpersonales (60%,65%,66%,45%, respectivamente), funciones/actividades basadas en la práctica y mejoramiento (57%,67%,60%,45%) y la forma como se emplean los conocimientos (47%,70%,67%,48%). Ocho docentes encuestados consideraron relevante el impacto del programa en habilidades interpersonales-(49%), conocimientos-(42%) y la interacción con colegas-(38%). En los padres de familia hay consenso en el cambio en habilidades interpersonales, funciones basadas en la práctica y mejoramiento y en actitudes-valores ético/morales. Dichos resultados están en paralelo con las observaciones plasmadas en las preguntas abiertas. Conclusiones: Se evidenció un impacto general positivo en la formación y desempeño profesional tras la participación como TPs dentro del programa; hallazgo que soporta aquellos publicados de experiencias académicas similares.

Neighborhood characteristics and the spatial concentration of crime: Evidence for Bogotá

Using a unique neighborhood crime dataset for Bogotá in 2011, this study uses a spatial econometric approach and examines the role of socioeconomic and agglomeration variables in explaining the variance of crime. It uses two different types of crime, violent crime represented in homicides and property crime represented in residential burglaries. These two types of crime are then measured in non-standard crime statistics that are created as the area incidence for each crime in the neighborhood. The existence of crime hotspots in Bogotá has been shown in most of the literature, and using these non-standard crime statistics at this neighborhood level some hotspots arise again, thus validating the use of a spatial approach for these new crime statistics. The final specification includes socioeconomic, agglomeration, land-use and visual aspect variables that are then included in a SARAR model an estimated by the procedure devised by Kelejian and Prucha (2009). The resulting coefficients and marginal effects show the relevance of these crime hotspots which is similar with most previous studies. However, socioeconomic variables are significant and show the importance of age, and education. Agglomeration variables are significant and thus more densely populated areas are correlated with more crime. Interestingly, both types of crimes do not have the same significant covariates. Education and young male population have a different sign for homicide and residential burglaries. Inequality matters for homicides while higher real estate valuation matters for residential burglaries. Finally, density impacts positively both crimes.

Poverty impacts of agricultural policy adjustments in an opening economy: the case of Colombia

We aim to contribute to the assessment of poverty impacts on the rural sector arising from agricultural policy adjustments in Colombia. For this we use an agriculture specialized static CGE model, jointly (sequentially) with a microsimulation model that allows for effective job relocation. Results indicate that the sectoral impact of the program implemented tends to be small and has considerable variability across crops. They also show that the highest impacts come from the irrigation and land improvements component of the program. Lastly, although it reduces poverty, poverty impacts are small and tend to concentrate in rural households toward the middle of the income distribution ladder.