Empirical study of correlated survival times for recurrent events with proportional hazards margins and the effect of correlation and censoring.

Background: In longitudinal studies where subjects experience recurrent incidents over a period of time, such as respiratory infections, fever or diarrhea, statistical methods are required to take into account the within-subject correlation. Methods: For repeated events data with censored failure, the independent increment (AG), marginal (WLW) and conditional (PWP) models are three multiple failure models that generalize Cox"s proportional hazard model. In this paper, we revise the efficiency, accuracy and robustness of all three models under simulated scenarios with varying degrees of within-subject correlation, censoring levels, maximum number of possible recurrences and sample size. We also study the methods performance on a real dataset from a cohort study with bronchial obstruction. Results: We find substantial differences between methods and there is not an optimal method. AG and PWP seem to be preferable to WLW for low correlation levels but the situation reverts for high correlations. Conclusions: All methods are stable in front of censoring, worsen with increasing recurrence levels and share a bias problem which, among other consequences, makes asymptotic normal confidence intervals not fully reliable, although they are well developed theoretically.

Rockfall susceptibility assessment and remote geological mapping with LiDAR point clouds

Characterizing the geological features and structures in three dimensions over inaccessible rock cliffs is needed to assess natural hazards such as rockfalls and rockslides and also to perform investigations aimed at mapping geological contacts and building stratigraphy and fold models. Indeed, the detailed 3D data, such as LiDAR point clouds, allow to study accurately the hazard processes and the structure of geologic features, in particular in vertical and overhanging rock slopes. Thus, 3D geological models have a great potential of being applied to a wide range of geological investigations both in research and applied geology projects, such as mines, tunnels and reservoirs. Recent development of ground-based remote sensing techniques (LiDAR, photogrammetry and multispectral / hyperspectral images) are revolutionizing the acquisition of morphological and geological information. As a consequence, there is a great potential for improving the modeling of geological bodies as well as failure mechanisms and stability conditions by integrating detailed remote data. During the past ten years several large rockfall events occurred along important transportation corridors where millions of people travel every year (Switzerland: Gotthard motorway and railway; Canada: Sea to sky highway between Vancouver and Whistler). These events show that there is still a lack of knowledge concerning the detection of potential rockfalls, making mountain residential settlements and roads highly risky. It is necessary to understand the main factors that destabilize rocky outcrops even if inventories are lacking and if no clear morphological evidences of rockfall activity are observed. In order to increase the possibilities of forecasting potential future landslides, it is crucial to understand the evolution of rock slope stability. Defining the areas theoretically most prone to rockfalls can be particularly useful to simulate trajectory profiles and to generate hazard maps, which are the basis for land use planning in mountainous regions. The most important questions to address in order to assess rockfall hazard are: Where are the most probable sources for future rockfalls located? What are the frequencies of occurrence of these rockfalls? I characterized the fracturing patterns in the field and with LiDAR point clouds. Afterwards, I developed a model to compute the failure mechanisms on terrestrial point clouds in order to assess the susceptibility to rockfalls at the cliff scale. Similar procedures were already available to evaluate the susceptibility to rockfalls based on aerial digital elevation models. This new model gives the possibility to detect the most susceptible rockfall sources with unprecented detail in the vertical and overhanging areas. The results of the computation of the most probable rockfall source areas in granitic cliffs of Yosemite Valley and Mont-Blanc massif were then compared to the inventoried rockfall events to validate the calculation methods. Yosemite Valley was chosen as a test area because it has a particularly strong rockfall activity (about one rockfall every week) which leads to a high rockfall hazard. The west face of the Dru was also chosen for the relevant rockfall activity and especially because it was affected by some of the largest rockfalls that occurred in the Alps during the last 10 years. Moreover, both areas were suitable because of their huge vertical and overhanging cliffs that are difficult to study with classical methods. Limit equilibrium models have been applied to several case studies to evaluate the effects of different parameters on the stability of rockslope areas. The impact of the degradation of rockbridges on the stability of large compartments in the west face of the Dru was assessed using finite element modeling. In particular I conducted a back-analysis of the large rockfall event of 2005 (265'000 m3) by integrating field observations of joint conditions, characteristics of fracturing pattern and results of geomechanical tests on the intact rock. These analyses improved our understanding of the factors that influence the stability of rock compartments and were used to define the most probable future rockfall volumes at the Dru. Terrestrial laser scanning point clouds were also successfully employed to perform geological mapping in 3D, using the intensity of the backscattered signal. Another technique to obtain vertical geological maps is combining triangulated TLS mesh with 2D geological maps. At El Capitan (Yosemite Valley) we built a georeferenced vertical map of the main plutonio rocks that was used to investigate the reasons for preferential rockwall retreat rate. Additional efforts to characterize the erosion rate were made at Monte Generoso (Ticino, southern Switzerland) where I attempted to improve the estimation of long term erosion by taking into account also the volumes of the unstable rock compartments. Eventually, the following points summarize the main out puts of my research: The new model to compute the failure mechanisms and the rockfall susceptibility with 3D point clouds allows to define accurately the most probable rockfall source areas at the cliff scale. The analysis of the rockbridges at the Dru shows the potential of integrating detailed measurements of the fractures in geomechanical models of rockmass stability. The correction of the LiDAR intensity signal gives the possibility to classify a point cloud according to the rock type and then use this information to model complex geologic structures. The integration of these results, on rockmass fracturing and composition, with existing methods can improve rockfall hazard assessments and enhance the interpretation of the evolution of steep rockslopes. -- La caractérisation de la géologie en 3D pour des parois rocheuses inaccessibles est une étape nécessaire pour évaluer les dangers naturels tels que chutes de blocs et glissements rocheux, mais aussi pour réaliser des modèles stratigraphiques ou de structures plissées. Les modèles géologiques 3D ont un grand potentiel pour être appliqués dans une vaste gamme de travaux géologiques dans le domaine de la recherche, mais aussi dans des projets appliqués comme les mines, les tunnels ou les réservoirs. Les développements récents des outils de télédétection terrestre (LiDAR, photogrammétrie et imagerie multispectrale / hyperspectrale) sont en train de révolutionner l'acquisition d'informations géomorphologiques et géologiques. Par conséquence, il y a un grand potentiel d'amélioration pour la modélisation d'objets géologiques, ainsi que des mécanismes de rupture et des conditions de stabilité, en intégrant des données détaillées acquises à distance. Pour augmenter les possibilités de prévoir les éboulements futurs, il est fondamental de comprendre l'évolution actuelle de la stabilité des parois rocheuses. Définir les zones qui sont théoriquement plus propices aux chutes de blocs peut être très utile pour simuler les trajectoires de propagation des blocs et pour réaliser des cartes de danger, qui constituent la base de l'aménagement du territoire dans les régions de montagne. Les questions plus importantes à résoudre pour estimer le danger de chutes de blocs sont : Où se situent les sources plus probables pour les chutes de blocs et éboulement futurs ? Avec quelle fréquence vont se produire ces événements ? Donc, j'ai caractérisé les réseaux de fractures sur le terrain et avec des nuages de points LiDAR. Ensuite, j'ai développé un modèle pour calculer les mécanismes de rupture directement sur les nuages de points pour pouvoir évaluer la susceptibilité au déclenchement de chutes de blocs à l'échelle de la paroi. Les zones sources de chutes de blocs les plus probables dans les parois granitiques de la vallée de Yosemite et du massif du Mont-Blanc ont été calculées et ensuite comparés aux inventaires des événements pour vérifier les méthodes. Des modèles d'équilibre limite ont été appliqués à plusieurs cas d'études pour évaluer les effets de différents paramètres sur la stabilité des parois. L'impact de la dégradation des ponts rocheux sur la stabilité de grands compartiments de roche dans la paroi ouest du Petit Dru a été évalué en utilisant la modélisation par éléments finis. En particulier j'ai analysé le grand éboulement de 2005 (265'000 m3), qui a emporté l'entier du pilier sud-ouest. Dans le modèle j'ai intégré des observations des conditions des joints, les caractéristiques du réseau de fractures et les résultats de tests géoméchaniques sur la roche intacte. Ces analyses ont amélioré l'estimation des paramètres qui influencent la stabilité des compartiments rocheux et ont servi pour définir des volumes probables pour des éboulements futurs. Les nuages de points obtenus avec le scanner laser terrestre ont été utilisés avec succès aussi pour produire des cartes géologiques en 3D, en utilisant l'intensité du signal réfléchi. Une autre technique pour obtenir des cartes géologiques des zones verticales consiste à combiner un maillage LiDAR avec une carte géologique en 2D. A El Capitan (Yosemite Valley) nous avons pu géoréferencer une carte verticale des principales roches plutoniques que j'ai utilisé ensuite pour étudier les raisons d'une érosion préférentielle de certaines zones de la paroi. D'autres efforts pour quantifier le taux d'érosion ont été effectués au Monte Generoso (Ticino, Suisse) où j'ai essayé d'améliorer l'estimation de l'érosion au long terme en prenant en compte les volumes des compartiments rocheux instables. L'intégration de ces résultats, sur la fracturation et la composition de l'amas rocheux, avec les méthodes existantes permet d'améliorer la prise en compte de l'aléa chute de pierres et éboulements et augmente les possibilités d'interprétation de l'évolution des parois rocheuses.

Territorialisation des politiques énergétiques dans l'agglomération franco-valdo-genevoise : la planification énergétique comme opportunité de réaménagement des zones frontières ?

La présente recherche traite des défis posés à l'action publique territoriale par la transition énergétique, transition désormais érigée au rang de priorité par les autorités françaises et suisses, comme plus globalement européennes. Elle prend pour cela appui sur une analyse des démarches de planification énergétique territoriale menées entre 2007 et 2014 sur le territoire franco-valdo-genevois (agglomération du « Grand-Genève »). Considérées comme des laboratoires d'expérimentation de la territorialisation des politiques énergétiques, ces démarches sont ici examinées selon une perspective institutionnaliste et pragmatiste visant à mettre lumière les éléments qui interviennent dans la délimitation du champ des possibles en matière d'action publique énergétique et territoriale. Ce positionnement découle des évolutions observées sur le territoire franco-valdo-genevois durant la période d'étude (chapitre 1). Il découle plus précisément du constat de récurrence de certains points de blocage rencontrés aussi bien dans les démarches de planification énergétique elles-mêmes que dans les travaux méthodologiques qui ont pu être réalisés parallèlement à ces démarches, dans le but d'en affiner les outils techniques et organisationnels de mise en oeuvre. Ainsi, le point de départ de la présente recherche est le constat selon lequel on peine tout autant à construire des solutions énergétiques appropriables et réalisables par les acteurs des territoires concernés qu'à reconfigurer les outils de production de ces solutions. De ce constat découle l'intérêt porté aux cadres institutionnels qui régissent ces planifications énergétiques territoriales. Définis comme l'ensemble des repères - formels et informels - qui rendent possibles en même temps qu'ils contraignent les interactions territorialisées entre les acteurs, ces cadres institutionnels sont placés au coeur de la grille de (re)lecture des expériences de planification énergétique territoriale établie au chapitre 2 de la thèse. En référence aux concepts institutionnalistes et pragmatistes sur lesquels elle prend appui, cette grille conduit à appréhender ces expériences comme autant d'enquêtes contribuant, à travers le travail de mobilisation et construction de représentations territoriales auquel elles donnent lieu, à l'équipement sociocognitif d'un champ d'intervention territorial spécifique. Partant de l'hypothèse selon laquelle les potentialités comme les limites associées à l'équipement sociocognitif de ce champ orientent les possibilités d'action collective, la réflexion consiste en une application de cette grille à une trentaine d'expériences de planification énergétique territoriale. Cette application s'effectue en deux temps, correspondant à deux niveaux de lecture de ces démarches. Le premier porte sur les dispositifs organisationnels et les modalités d'interactions entre les cultures d'action qu'elles réunissent (chapitre 3). Le second se concentre davantage sur les supports cognitifs (représentations territoriales) autour desquels se structurent ces interactions (chapitre 4). Présentés dans le dernier chapitre de la thèse (chapitre 5), les enseignements tirés de ce travail de réexamen des démarches franco-valdo-genevoises de planification énergétique territoriale sont de deux ordres. Ils portent d'abord sur les caractéristiques des cadres institutionnels existants, la manière dont ils orientent ces démarches et délimitent les évolutions possibles dans les modes d'action collective et plus particulièrement d'action publique qui y sont associés. Mais ils portent aussi sur les potentiels de changement associés à ces démarches, et sur les pistes envisageables pour mieux valoriser es potentiels, dont l'activation passe par des évolutions profondes des systèmes institutionnels en place. -- In France as in Switzerland, local authorities stand out as leading players of energy transition, a transition that requires an important renewal of public intervention instruments. It is the stakes and the conditions of such a renewal that the present work aims to examine, based on the experiments of territorial energy planning led on the franco-valdo-genevan cross-border territory. Conceived as initiatives of relocation of the energy supply system, these energy planning initiatives are examined through an institutionalist and pragmatic « reading template ». This « reading template » consists of seeing these energy planning initiatives as pragmatist inquiries aiming, through a collective work of cognitive equipment of the territorial franco-valdo-genevan field of intervention, at the reconstruction of the means of coordination between people about their material, organizational and political territory. It opens towards a double reading of the energy planning initiatives. The first one concentrates on the organizational dimension of these inquiries - i.e. on the cultures of action which they gather and the modalities of interaction between them - whereas the second focuses on the cognitive substance which represents the medium of the interactions. This double reading provides insights at various levels. The first one concerns the (cognitive) territorial field of intervention that these energy-planning experiments contribute to draw. A field which, although better and better characterized in its technical dimensions, remains at the same time limited and " deformed " so that it values more the fossil energy systems, from which we want to release ourselves, than the renewable ones, which we would like to replace them with. The second level of teaching concerns the processes of production of territorial knowledge (PPTK) which presides over the demarcation and « equipment » of the territorial field of intervention. Examined through the institutional norms and the culture of action at stake in them, this PPTK turns out to create a sociocognitive "cross-border" area, the kind of area that could shelter the desired reconfigurations...on the condition that they are beforehand correctly "equipped", in cognitive and also in organizational terms. The determining factor for the quality of this equipment is concentrated in the third category of teaching. Starting with the opportunities created by these energy planning experiments concerning the renewal of public intervention instruments, these elements also allow us to take a new look at the urban area project under construction in this cross-border territory, a project th t shows itself closely linked to the energy experiments through a common challenge of territorialisation.

Engineering Geology for Society and Territory: volume 2: landslide processes

This book is one out of 8 IAEG XII Congress volumes, and deals with Landslide processes, including: field data and monitoring techniques, prediction and forecasting of landslide occurrence, regional landslide inventories and dating studies, modeling of slope instabilities and secondary hazards (e.g. impulse waves and landslide-induced tsunamis, landslide dam failures and breaching), hazard and risk assessment, earthquake and rainfall induced landslides, instabilities of volcanic edifices, remedial works and mitigation measures, development of innovative stabilization techniques and applicability to specific engineering geological conditions, use of geophysical techniques for landslide characterization and investigation of triggering mechanisms. Focuses is given to innovative techniques, well documented case studies in different environments, critical components of engineering geological and geotechnical investigations, hydrological and hydrogeological investigations, remote sensing and geophysical techniques, modeling of triggering, collapse, runout and landslide reactivation, geotechnical design and construction procedures in landslide zones, interaction of landslides with structures and infrastructures and possibility of domino effects. The Engineering Geology for Society and Territory volumes of the IAEG XII Congress held in Torino from September 15-19, 2014, analyze the dynamic role of engineering geology in our changing world and build on the four main themes of the congress: environment, processes, issues, and approaches.

An interactive web-GIS tool for risk analysis: a case study in the Fella River basin, Italy

This paper presents a prototype of an interactive web-GIS tool for risk analysis of natural hazards, in particular for floods and landslides, based on open-source geospatial software and technologies. The aim of the presented tool is to assist the experts (risk managers) in analysing the impacts and consequences of a certain hazard event in a considered region, providing an essential input to the decision-making process in the selection of risk management strategies by responsible authorities and decision makers. This tool is based on the Boundless (OpenGeo Suite) framework and its client-side environment for prototype development, and it is one of the main modules of a web-based collaborative decision support platform in risk management. Within this platform, the users can import necessary maps and information to analyse areas at risk. Based on provided information and parameters, loss scenarios (amount of damages and number of fatalities) of a hazard event are generated on the fly and visualized interactively within the web-GIS interface of the platform. The annualized risk is calculated based on the combination of resultant loss scenarios with different return periods of the hazard event. The application of this developed prototype is demonstrated using a regional data set from one of the case study sites, Fella River of northeastern Italy, of the Marie Curie ITN CHANGES project.

Analysis of space-time environmental data in complex regions

This thesis develops a comprehensive and a flexible statistical framework for the analysis and detection of space, time and space-time clusters of environmental point data. The developed clustering methods were applied in both simulated datasets and real-world environmental phenomena; however, only the cases of forest fires in Canton of Ticino (Switzerland) and in Portugal are expounded in this document. Normally, environmental phenomena can be modelled as stochastic point processes where each event, e.g. the forest fire ignition point, is characterised by its spatial location and occurrence in time. Additionally, information such as burned area, ignition causes, landuse, topographic, climatic and meteorological features, etc., can also be used to characterise the studied phenomenon. Thereby, the space-time pattern characterisa- tion represents a powerful tool to understand the distribution and behaviour of the events and their correlation with underlying processes, for instance, socio-economic, environmental and meteorological factors. Consequently, we propose a methodology based on the adaptation and application of statistical and fractal point process measures for both global (e.g. the Morisita Index, the Box-counting fractal method, the multifractal formalism and the Ripley's K-function) and local (e.g. Scan Statistics) analysis. Many measures describing the space-time distribution of environmental phenomena have been proposed in a wide variety of disciplines; nevertheless, most of these measures are of global character and do not consider complex spatial constraints, high variability and multivariate nature of the events. Therefore, we proposed an statistical framework that takes into account the complexities of the geographical space, where phenomena take place, by introducing the Validity Domain concept and carrying out clustering analyses in data with different constrained geographical spaces, hence, assessing the relative degree of clustering of the real distribution. Moreover, exclusively to the forest fire case, this research proposes two new methodologies to defining and mapping both the Wildland-Urban Interface (WUI) described as the interaction zone between burnable vegetation and anthropogenic infrastructures, and the prediction of fire ignition susceptibility. In this regard, the main objective of this Thesis was to carry out a basic statistical/- geospatial research with a strong application part to analyse and to describe complex phenomena as well as to overcome unsolved methodological problems in the characterisation of space-time patterns, in particular, the forest fire occurrences. Thus, this Thesis provides a response to the increasing demand for both environmental monitoring and management tools for the assessment of natural and anthropogenic hazards and risks, sustainable development, retrospective success analysis, etc. The major contributions of this work were presented at national and international conferences and published in 5 scientific journals. National and international collaborations were also established and successfully accomplished. -- Cette thèse développe une méthodologie statistique complète et flexible pour l'analyse et la détection des structures spatiales, temporelles et spatio-temporelles de données environnementales représentées comme de semis de points. Les méthodes ici développées ont été appliquées aux jeux de données simulées autant qu'A des phénomènes environnementaux réels; nonobstant, seulement le cas des feux forestiers dans le Canton du Tessin (la Suisse) et celui de Portugal sont expliqués dans ce document. Normalement, les phénomènes environnementaux peuvent être modélisés comme des processus ponctuels stochastiques ou chaque événement, par ex. les point d'ignition des feux forestiers, est déterminé par son emplacement spatial et son occurrence dans le temps. De plus, des informations tels que la surface bru^lée, les causes d'ignition, l'utilisation du sol, les caractéristiques topographiques, climatiques et météorologiques, etc., peuvent aussi être utilisées pour caractériser le phénomène étudié. Par conséquent, la définition de la structure spatio-temporelle représente un outil puissant pour compren- dre la distribution du phénomène et sa corrélation avec des processus sous-jacents tels que les facteurs socio-économiques, environnementaux et météorologiques. De ce fait, nous proposons une méthodologie basée sur l'adaptation et l'application de mesures statistiques et fractales des processus ponctuels d'analyse global (par ex. l'indice de Morisita, la dimension fractale par comptage de boîtes, le formalisme multifractal et la fonction K de Ripley) et local (par ex. la statistique de scan). Des nombreuses mesures décrivant les structures spatio-temporelles de phénomènes environnementaux peuvent être trouvées dans la littérature. Néanmoins, la plupart de ces mesures sont de caractère global et ne considèrent pas de contraintes spatiales com- plexes, ainsi que la haute variabilité et la nature multivariée des événements. A cet effet, la méthodologie ici proposée prend en compte les complexités de l'espace géographique ou le phénomène a lieu, à travers de l'introduction du concept de Domaine de Validité et l'application des mesures d'analyse spatiale dans des données en présentant différentes contraintes géographiques. Cela permet l'évaluation du degré relatif d'agrégation spatiale/temporelle des structures du phénomène observé. En plus, exclusif au cas de feux forestiers, cette recherche propose aussi deux nouvelles méthodologies pour la définition et la cartographie des zones périurbaines, décrites comme des espaces anthropogéniques à proximité de la végétation sauvage ou de la forêt, et de la prédiction de la susceptibilité à l'ignition de feu. A cet égard, l'objectif principal de cette Thèse a été d'effectuer une recherche statistique/géospatiale avec une forte application dans des cas réels, pour analyser et décrire des phénomènes environnementaux complexes aussi bien que surmonter des problèmes méthodologiques non résolus relatifs à la caractérisation des structures spatio-temporelles, particulièrement, celles des occurrences de feux forestières. Ainsi, cette Thèse fournit une réponse à la demande croissante de la gestion et du monitoring environnemental pour le déploiement d'outils d'évaluation des risques et des dangers naturels et anthro- pogéniques. Les majeures contributions de ce travail ont été présentées aux conférences nationales et internationales, et ont été aussi publiées dans 5 revues internationales avec comité de lecture. Des collaborations nationales et internationales ont été aussi établies et accomplies avec succès.

An analysis of the evolution of hydrometeorological extremes in newspapers: the case of Catalonia, 1982-2006

This contribution analyzes the evolution of perception of certain natural hazards over the past 25 years in a Mediterranean region. Articles from newspapers have been used as indicator. To this end a specific Spanish journal has been considered and an ACCESS database has been created with the summarized information from each news item. The database includes data such as the location of each specific article in the newspaper, its length, the number of pictures and figures, the headlines and a summary of the published information, including all the instrumental data. The study focused on hydrometeorological extremes, mainly floods and droughts, in the northeast of the Iberian Peninsula. The number of headlines per event, trends and other data have been analyzed and compared with "measured" information, in order to identify any bias that could lead to an erroneous perception of the phenomenon. The SPI index (a drought index based on standardized accumulated precipitation) has been calculated for the entire region, and has been used for the drought analysis, while a geodatabase implemented on a GIS built for all the floods recorded in Catalonia since 1900 (INUNGAMA) has been used to analyze flood evolution. Results from a questionnaire about the impact of natural hazards in two specific places have been also used to discuss the various perceptions between rural and urban settings. Results show a better correlation between the news about drought or water scarcity and SPI than between news on floods in Catalonia and the INUNGAMA database. A positive trend has been found for non-catastrophic floods, which is explained by decrease of the perception thresholds, the increase of population density in the most flood-prone areas and changes in land use.

Avaluació dels nivells de nitrats i duresa a l'aigua de consum a quatre zones d'Espanya participants a l'estudi epidemiològic Infància i Medi Ambientl (INMA)

L’aigua és un dels components bàsics per a la vida i una font d’exposició a contaminants ubiqua, ja que tota la població en consumeix. L’estudi epidemiològic INMA avaluarà si l’exposició a nitrats durant l’embaràs i a la duresa de l’aigua durant la infància es relaciona amb el baix pes al néixer i l’èczema atòpica, respectivament. Objectiu: Fer una avaluació dels nivells de nitrats i duresa de l’aigua en aigua de consum de la població de l’estudi INMA. Metodologia: l’estudi descriptiu realitzat a quatre de les set cohorts INMA, a Astúries, Guipúscoa, Sabadell i València. S’ha recopilat dades dels nivells de nitrats i duresa a l’aigua de consum dels municipis durant el període d’interès (2003 al 2008 i 2004 al 2012), a través d’ajuntaments i companyies d’aigua. S’ha calculat la mitjana, la desviació estàndard, el màxim i el mínim dels nivells de nitrat i de duresa en total i segons l’àrea geogràfica, l’any i l’estació. A Sabadell s’han fet tres mostrejos d’aigua per analitzar la duresa a diferents punts de la ciutat. Resultats: el nivell promig de nitrats (mg/L NO3-) és de 4,2 a Astúries, 4,0 a Guipúscoa, 9,2 a Sabadell i 15,2 a València. El nivell promig de duresa (mg/L CaCO3) és de 89,1 a Astúries, 132,7 al Guipúscoa, 178,3 a València i 230,9 a Sabadell. En l’anàlisi que es va realitzar a Sabadell, es detecta una duresa lleugerament inferior a la reportada sense variabilitat geogràfica. No s’observa una pauta clara de variabilitat estacional ni de variabilitat temporal tant per nitrats com per duresa. Conclusions: S’ha detectat variabilitat en els nivells de nitrats i duresa de l’aigua a les zones d’estudi. Els nivells de nitrats són moderats i els més alts es troben a zones agrícoles de València. La duresa de l’aigua és força alta degut al domini calcari dels subsòls de les zones d’estudi.

Food Safety Testing: Rapid Molecular Methods for Chemical and Biological Hazards

The central goal of food safety policy in the European Union (EU) is to protect consumer health by guaranteeing a high level of food safety throughout the food chain. This goal can in part be achieved by testing foodstuffs for the presence of various chemical and biological hazards. The aim of this study was to facilitate food safety testing by providing rapid and user-friendly methods for the detection of particular food-related hazards. Heterogeneous competitive time-resolved fluoroimmunoassays were developed for the detection of selected veterinary residues, that is coccidiostat residues, in eggs and chicken liver. After a simplified sample preparation procedure, the immunoassays were performed either in manual format with dissociation-enhanced measurement or in automated format with pre-dried assay reagents and surface measurement. Although the assays were primarily designed for screening purposes providing only qualitative results, they could also be used in a quantitative mode. All the developed assays had good performance characteristics enabling reliable screening of samples at concentration levels required by the authorities. A novel polymerase chain reaction (PCR)-based assay system was developed for the detection of Salmonella spp. in food. The sample preparation included a short non-selective pre-enrichment step, after which the target cells were collected with immunomagnetic beads and applied to PCR reaction vessels containing all the reagents required for the assay in dry form. The homogeneous PCR assay was performed with a novel instrument platform, GenomEra^™, and the qualitative assay results were automatically interpreted based on end-point time-resolved fluorescence measurements and cut-off values. The assay was validated using various food matrices spiked with sub-lethally injured Salmonella cells at levels of 1-10 colony forming units (CFU)/25 g of food. The main advantage of the system was the exceptionally short time to result; the entire process starting from the pre-enrichment and ending with the PCR result could be completed in eight hours. In conclusion, molecular methods using state-of-the-art assay techniques were developed for food safety testing. The combination of time-resolved fluorescence detection and ready-to-use reagents enabled sensitive assays easily amenable to automation. Consequently, together with the simplified sample preparation, these methods could prove to be applicable in routine testing.

Aplicació de tècniques geofísiques electromagnètiques a la localització de zones afectades per abocaments incontrolats de residus

Increase of the metropolitan area of cities provoking a progressive settlement of zones that previously had a different territorial use. These zones are usually located within city houndaries and for many years have been affected hy the waste of many kinds of residues. Qualitative analysis of the electrical behaviour of soil, based on maps and cross sections of apparent conductivity, allows us to locate anomalies generated by the wastes. Moreover, the electrornagnetic techniques (EM-31 and EM-34 Geonics devices) are cheaper than other survey methods. Two examples in the campus of the University of Girona, in the southern area of Girona city, illustrate the environmental problem and the applicability of the geophysical method

Geomorphological mapping of granite zones in the province of Girona (Catalunya, Spain)

Since 1978, the unity of Geodynamics of the University of Girona has been publishing a series of detailed geological and geomorphological maps of different municipal terms of the Province of Girona, mainly on the scale of 1:10.000, situated for the major part in the Littoral and Prelittoral mountain ranges of the Cadena Costera Catalana. These mountain ranges are constituted of materials belonging to the palaeozoic era, basically metamorphous and igneous rocks (plutomc and hypoabyssal rocks)

Effects of solar activity and climate variability on large floods in Switzerland

The paper presents the variability of major floods in Switzerland for the period 1800-2008 from a summer index (INU). The index is constructed from the damage caused by flooding, with the aim of establishing the possible influence of the solar and climate variability on the major floods. The coincidence of flood-rich periods with those observed in other regions of different climate and fluvial regimes suggests that climate forcings and changes in the general circulation of the atmosphere are those who govern the appearance of these high-frequency temporal clusters.