Association between GIS-based exposure to urban air pollution during pregnancy and birth weight in the INMA Sabadell Cohort

Background: There is growing evidence that traffic-related air pollution reduces birth weight. Improving exposure assessment is a key issue to advance in this research area.Objective: We investigated the effect of prenatal exposure to traffic-related air pollution via geographic information system (GIS) models on birth weight in 570 newborns from the INMA (Environment and Childhood) Sabadell cohort.Methods: We estimated pregnancy and trimester-specific exposures to nitrogen dioxide and aromatic hydrocarbons [benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene (BTEX)] by using temporally adjusted land-use regression (LUR) models. We built models for NO2 and BTEX using four and three 1-week measurement campaigns, respectively, at 57 locations. We assessed the relationship between prenatal air pollution exposure and birth weight with linear regression models. We performed sensitivity analyses considering time spent at home and time spent in nonresidential outdoor environments during pregnancy.Results: In the overall cohort, neither NO2 nor BTEX exposure was significantly associated with birth weight in any of the exposure periods. When considering only women who spent < 2 hr/day in nonresidential outdoor environments, the estimated reductions in birth weight associated with an interquartile range increase in BTEX exposure levels were 77 g [95% confidence interval (CI), 7–146 g] and 102 g (95% CI, 28–176 g) for exposures during the whole pregnancy and the second trimester, respectively. The effects of NO2 exposure were less clear in this subset.Conclusions: The association of BTEX with reduced birth weight underscores the negative role of vehicle exhaust pollutants in reproductive health. Time–activity patterns during pregnancy complement GIS-based models in exposure assessment.

GIS-based debris flow source and runout susceptibility assessment from DEM data - a case study in NW Nicaragua

In October 1998, Hurricane Mitch triggered numerous landslides (mainly debris flows) in Honduras and Nicaragua, resulting in a high death toll and in considerable damage to property. The potential application of relatively simple and affordable spatial prediction models for landslide hazard mapping in developing countries was studied. Our attention was focused on a region in NW Nicaragua, one of the most severely hit places during the Mitch event. A landslide map was obtained at 1:10 000 scale in a Geographic Information System (GIS) environment from the interpretation of aerial photographs and detailed field work. In this map the terrain failure zones were distinguished from the areas within the reach of the mobilized materials. A Digital Elevation Model (DEM) with 20 m×20 m of pixel size was also employed in the study area. A comparative analysis of the terrain failures caused by Hurricane Mitch and a selection of 4 terrain factors extracted from the DEM which, contributed to the terrain instability, was carried out. Land propensity to failure was determined with the aid of a bivariate analysis and GIS tools in a terrain failure susceptibility map. In order to estimate the areas that could be affected by the path or deposition of the mobilized materials, we considered the fact that under intense rainfall events debris flows tend to travel long distances following the maximum slope and merging with the drainage network. Using the TauDEM extension for ArcGIS software we generated automatically flow lines following the maximum slope in the DEM starting from the areas prone to failure in the terrain failure susceptibility map. The areas crossed by the flow lines from each terrain failure susceptibility class correspond to the runout susceptibility classes represented in a runout susceptibility map. The study of terrain failure and runout susceptibility enabled us to obtain a spatial prediction for landslides, which could contribute to landslide risk mitigation.

Detection of Body Dump Sites and Clandestine Burials: a GIS-Based Landscape Approach

Forensic archaeology has been of inestimable help in the location and excavation of clandestine burials (Hunter 1996a:16-17, 1996b; Killam 2004; Levine et al. 1984). Landscape archaeology techniques have been adapted and widely applied for such purposes. In this article, an adaptation of one of the most common applications of archaeological GIS, that is predictive site location, is applied to the detection of body dump sites and clandestine burial sites, bringing together in the process the fields of landscape archaeology, forensic sciences, and GIS.

Forma Tarraconis: GIS aplicado a la arqueología urbana

Desde aquel incipiente interés renacentista del siglo XVI hasta la profesionalización de la arqueología en la actualidad, la ingente actividad realizada en Tarragona ha necesitado de formas de registrarla y organizarla, a fin de ser estudiada en el contexto diacrónico general de la ciudad. Esta tarea se ha visto favorecida en el último decenio del siglo pasado por la aparición y adopción de una herramienta informática que no fue diseñada específicamente para la Arqueología. El GIS o SIG, se ha convertido en un instrumento básico e indispensable para cualquier ciudad que tenga un mínimo bagaje patrimonial. Prueba de ello son las publicaciones de Cartas Arqueológicas obtenidas a partir de este software, o sin ir mucho más lejos, los trabajos presentados en este simposio. Presentamos a continuación la experiencia de Tarragona en la creación de un programa, bajo soporte GIS, para la gestión de la actividad arqueológica. Previamente contextualizaremos esta experiencia ya que es justa heredera de iniciativas individuales y de equipos y proyectos previos que trataron, con mucha menor suerte que no éxito, de organizar y poner orden en la maltrecha documentación arqueológica de nuestra ciudad. Describiremos posteriormente las funcionalidades básicas de este programa, su arquitectura y las aplicaciones realizadas en el desarrollo de sendos proyectos de estudio de la ciudad. En este último caso nos centraremos, principalmente, en el proyecto Planimetria Arqueològica de Tàrraco, impulsado por el Museu d’Història del Ayuntamiento de Tarragona y el Institut Català d’Arqueologia Clàssica, y que ha contado con la colaboración de la Generalitat de Catalunya para su edición. Seguidamente veremos como el uso de la información en capas registrada en el GIS combinada con la inclusión de la cartografía histórica de una ciudad permiten el análisis de problemas arqueológicos irresolubles sólo con los datos estrictamente arqueológicos. En este caso se aplicará sobre la validación de la morfología urbana de Tarraco propuesta por Macias (2000a). Por último se hará una reflexión sobre cuales podrían ser las mejoras aplicables sobre el programa, en previsión de futuras revisiones del mismo.

Restitución 3D de la topografía de la antigua ciudad de Tarraco en un entorno SIG: propuestas metodológicas y primeros resultados

Durante los últimos años el Institut Català d’Arquelogia Clàssica, el Museu d’Història de Tarragona, contando con la colaboración de la Generalitat de Catalunya, han desarrallado el proyecto Planimetría Arqueológica de Tárraco, destinado a la elaboración de una planta arqueológica global en la cual se recogieran intervenciones y noticias referentes a los hallazgos arqueológicos existentes. Este trabajo fue publicado utilizando como plataforma de trabajo un SIG construido para tal fin (Macias et al. 2007). Sin embargo, un problema de difícil solución arqueológica venía dado por las transformaciones urbanísticas de la ciudad, sufridas en su mayor parte a lo largo de los siglos XIX y XX. Éstas habían provocado la pérdida irremediable de gran parte de la elevación que acogiera la ciudad romana, cambiando substancialmente su aspecto original. Ante esta situación y como proyecto paralelo a la realización de la Planimetría Arqueológica de Tarragona se plantearon formas de cubrir este vacío. Se presenta en esta comunicación una propuesta metodológica para la reconstrucción de los grandes «vacíos topográficos » originados por la evolución urbanística de Tarragona mediante la obtención e integración en un SIG de diversos tipos de información documental. En estas zonas rebajadas no resulta posible la obtención de información estratigráfica y arqueológica, por lo que es imprescindible la definición de vías metodológicas alternativas basadas en la extrapolación de datos extraídos de la cartografía histórica, panorámicas del XVI o fotografías tomadas en los siglos XIX y XX. Esta técnica permite aplicar los resultados obtenidos en los nuevos análisis interpretativos, complementando así la interpretación arqueológica de la topografía urbana de la ciudad romana. A partir de esta información, y aplicando funciones y técnicas de interpolación propias de un GIS, se propone aquí un modelo de relieve de la ciudad de Tarraco.

The Application of 3D Reconstruction Techniques in the Analysis of Ancient Tarraco’s Urban Topography

The widespread implementation of GIS-based 3D topographical models has been a great aid in the development and testing of archaeological hypotheses. In this paper, a topographical reconstruction of the ancient city of Tarraco, the Roman capital of the Tarraconensis province, is presented. This model is based on topographical data obtained through archaeological excavations, old photographic documentation, georeferenced archive maps depicting the pre-modern city topography, modern detailed topographical maps and differential GPS measurements. The addition of the Roman urban architectural features to the model offers the possibility to test hypotheses concerning the ideological background manifested in the city shape. This is accomplished mainly through the use of 3D views from the main city accesses. These techniques ultimately demonstrate the ‘theatre-shaped’ layout of the city (to quote Vitrubius) as well as its southwest oriented architecture, whose monumental character was conceived to present a striking aspect to visitors, particularly those arriving from the sea.

Model-based diagnosis system: application to constructed wetlands

Report for the scientific sojourn carried out at the Model-based Systems and Qualitative Reasoning Group (Technical University of Munich), from September until December 2005. Constructed wetlands (CWs), or modified natural wetlands, are used all over the world as wastewater treatment systems for small communities because they can provide high treatment efficiency with low energy consumption and low construction, operation and maintenance costs. Their treatment process is very complex because it includes physical, chemical and biological mechanisms like microorganism oxidation, microorganism reduction, filtration, sedimentation and chemical precipitation. Besides, these processes can be influenced by different factors. In order to guarantee the performance of CWs, an operation and maintenance program must be defined for each Wastewater Treatment Plant (WWTP). The main objective of this project is to provide a computer support to the definition of the most appropriate operation and maintenance protocols to guarantee the correct performance of CWs. To reach them, the definition of models which represent the knowledge about CW has been proposed: components involved in the sanitation process, relation among these units and processes to remove pollutants. Horizontal Subsurface Flow CWs are chosen as a case study and the filtration process is selected as first modelling-process application. However, the goal is to represent the process knowledge in such a way that it can be reused for other types of WWTP.

Desarrollo de nuevas Funcionalidades para la Aplicación WebMap del GIS Corporativo de una empresa de distribución de agua en alta

La present memòria és el resultat del Projecte final del Màster en Tecnologia de la Informació Geogràfica, realitzat en la Universitat Autònoma de Barcelona, curs 2007-2009. Aquest document és per a il•lustrar el treball realitzat en a l'empresa Auding en conjunt en col•laboració amb la Universitat Autònoma de Barcelona. L'objectiu del projecte va ser és la creació de noves funcionalitats per a un GIS corporatiu d'una empresa de distribució d'aigua en alta. Aquest GIS és estratègic, doncs ja que permet millorar el tractament de la informació, la difusió de les dades, la planificació i la presa de decisions corporatiu.

Implantació d'una solució SIG per al'ajuda a la presa de decisions perl'explotació de recursos del subsòl

Aquest projecte té com a objectiu la implementació d¿un Sistema d¿InformacióGeogràfic (SIG) que permeti ajudar en la presa de decisions per l¿explotació derecursos del subsòl.

Construcció d'un GIS de base municipal amb assignació automàtica del nom de carrer a les illes d'habitatges de la població de Terrassa

Aquest treball fi de carrera es basa en un estudi i posterior aplicació dels sistemes d'informació geogràfica (GIS), branca que pertany a l'àrea de les bases de dades.

Personalized touristic routes implementing semantic web on GIS

Nowadays, when a user is planning a touristic route is very difficult to find out which are the best places to visit. The user has to choose considering his/her preferences due to the great quantity of information it is possible to find in the web and taking into account it is necessary to do a selection, within small time because there is a limited time to do a trip. In Itiner@ project, we aim to implement Semantic Web technology combined with Geographic Information Systems in order to offer personalized touristic routes around a region based on user preferences and time situation. Using ontologies it is possible to link, structure, share data and obtain the result more suitable for user's preferences and actual situation with less time and more precisely than without ontologies. To achieve these objectives we propose a web page combining a GIS server and a touristic ontology. As a step further, we also study how to extend this technology on mobile devices due to the raising interest and technological progress of these devices and location-based services, which allows the user to have all the route information on the hand when he/she does a touristic trip. We design a little application in order to apply the combination of GIS and Semantic Web in a mobile device.

Alternation and Cooperation in a Two-party System: Implications for Resource-Based Developing Economies

This paper studies cooperation in a political system dominated by two opportunistic parties competing in a resource-based economy. Since a binding agreement as an external solution might be difficult to enforce due to the close association between the incumbent party and the government, the paper explores the extent to which co-operation between political parties that alternate in office can rely on self-enforcing strategies to provide an internal solution. We show that, for appropriate values of the probability of re-election and the discount factor cooperation in maintaining the value of a state variable is possible, but fragile. Another result is that, in such political framework, debt decisions contain an externality element linked to electoral incentives that creates a bias towards excessive borrowing.

Improving college access and success for low-income students: Evidence from a large need-based grant program

Using comprehensive administrative data on France's single largest financialaid program, this paper provides new evidence on the impact of large-scaleneed-based grant programs on the college enrollment decisions, persistenceand graduation rates of low-income students. We exploit sharp discontinuitiesin the grant eligibility formula to identify the impact of aid on student outcomesat different levels of study. We find that eligibility for an annual cashallowance of 1,500 euros increases college enrollment rates by up to 5 percentagepoints. Moreover, we show that need-based grants have positive effectson student persistence and degree completion.

Social reciprocity measures based on dyadic discrepancies: Methodological review and software development

This paper examines statistical analysis of social reciprocity at group, dyadic, and individual levels. Given that testing statistical hypotheses regarding social reciprocity can be also of interest, a statistical procedure based on Monte Carlo sampling has been developed and implemented in R in order to allow social researchers to describe groups and make statistical decisions.