Effects of radiofrequency electromagnetic field exposure on sleep quality

The use of wireless communication devices, which emit radiofrequency electromagnetic fields (RF-EMF), has increased in the past decades. According to the World Health Organization (WHO) mobile phone use is ubiquitous with an estimated 4.6 billion subscriptions globally. The missing knowledge about a biological mechanism and the attribution of non-specific symptoms of ill health to RF-EMF has led to an increased public concern about possible adverse health effects from this radiation. One of the most often reported symptoms due to RF-EMF exposure are sleep disturbances. In several randomised double-blind human laboratory studies, changes in the sleep electroencephalogram (EEG) after exposure to RF-EMF were observed. The impact of these small changes on sleep quality and therefore on general well-being is unclear. Previous epidemiological studies have used a cross-sectional design, which is not appropriate for establishing causal relationships between exposure and outcome. Studies with a cohort design are therefore needed. Additionally, exposure assessment was mostly inadequate or only parts of the real exposure situation were taken into account. Personal measurement devices (exposimeters) have become available a few years age. In large epidemiological studies, it is very time-consuming and costly to use such devices. Other exposure assessment methods are therefore needed. The main aim of this thesis was to investigate the association between personal RF-EMF exposure and sleep quality by using objective as well as subjective data. To predict personal exposure to RF-EMF a comprehensive exposure assessment method was applied. This thesis was part of the QUALIFEX project (a prospective cohort study on radiofrequency electromagnetic field exposure and health related quality of life) which is embedded in the National Research Program 57 (NRP-57) about non-ionising radiation. The health effect of RF-EMF exposure was investigated in a cohort study which consisted of a baseline survey in May 2008 and a follow-up survey one year later. Questionnaires entitled „Environment and Health“ were sent out to 1375 randomly selected study participants in the region of Basel (Switzerland). Information on sleep quality, on exposure relevant factors and on various confounding factors was collected. By means of a pre-study, which was not part of this thesis, a comprehensive exposure assessment method was developed. To predict personal exposure to far-field RF-EMF (e.g mobile phone base stations or radio transmitters), a validated full exposure prediction model was used which was developed based personal exposure measurements of 166 study participants who took part in a pre-study. Exposure to close to body sources was assessed using self-reported data on mobile phone and cordless phone use. Objective data of mobile phone use from network operators for participants who gave informed consent were additionally collected. For a nested sleep study, 120 participants out of the baseline survey took part in a nested sleep study to verify our previous results. Sleep quality and sleep behavior was assessed using actigraphy and exposure to RF-EMF was measured by means of personal exposimeters. For the baseline survey, mean calculated RF-EMF exposure to all relevant sources of all 1375 study participants was 0.12 mW/m2 (0.21 V/m). Exposure at the follow-up survey was 0.13 mW/m2 (0.22 V/m) and therefore comparable with the baseline exposure. No consistent association between RF-EMF exposure and self-reported sleep quality neither in the baseline analysis (cross-sectional analysis) nor in the cohort analysis (longitudinal analysis) was observed. In the nested sleep study, objective data on exposure and sleep quality did not yield any association between exposure and sleep quality. The QUALIFEX project was the first study which applied a cohort design to investigate the association between RF-EMF exposure and sleep quality. Additionally, we were able to verify our results of the cohort study with objective data obtained in a nested sleep study. Overall, we found no consistent association between self-reported as well as objectively measured sleep quality and exposure to relevant RF-EMF sources in everyday life. Our results increase the evidence for a true absence of an effect of RF-EMF exposure on sleep quality. Our study used a very comprehensive exposure assessment method which included far-field sources as well as close to body sources. In general, exposure levels were very small and changes between the baseline and the follow-up survey were marginal. Hence, with our study no conclusions can be drawn regarding potential health effects of higher exposure levels. In future studies, more data on long-term effects have to be collected. Additionally, the exposure situation in everyday life should be monitored because new technologies operating with RF-EMF are continuously arising

Modelization of generation cost and demand uncertainties in power system optimization problems and in nodal marginal price calculations

Tese de doutoramento. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto, Instituto Politécnico de Leiria. 200

Life cycle assessment of agre-food systems

Life Cycle Assessment (LCA) is the internationally recognized method to assess the environmental impacts of products and services. Its application to agri-food systems in developing or emerging contexts is recent and represents many challenges of scientific, partnerial and operational nature. With more than 10 years of scientific and field experience, the CIRAD LCA team has synthesized, with other internationally recognized experts, the best knowledge and approaches available to apply LCA under these conditions. This operational guide is a useful tool for LCA practitioners; it provides best practice recommendations to carry out LCA studies on agri-food products in developing and emerging contexts

Evaluación del potencial de sólidos monolíticos modificados con nanopartículas en técnicas de microextracción

1. Introducción o motivación de la tesis La Química Analítica es la ciencia que desarrolla, optimiza y aplica procesos de medida para obtener información sobre la composición y la naturaleza (bio)química de la materia. La etapa de tratamiento de la muestra es la que más afecta a la calidad de la información analítica, ya que se considera la principal fuente de error del proceso analítico. En general, las técnicas de tratamiento de muestra juegan un papel importante en la mejora de la sensibilidad, a través de la preconcentración de los analitos, y de la selectividad, por su aislamiento de la matriz de la muestra. La simplificación, automatización y miniaturización de esta etapa han sido tendencias clave que han marcado la evolución de esta disciplina en la última década. En este contexto, es necesario el desarrollo de nuevas fases extractantes más eficientes para que la reducción de dimensiones no afecte negativamente a las propiedades analíticas básicas [1, 2]. Los logros alcanzados en las técnicas de microextracción en fase sólida están en gran parte marcados por el empleo de nanopartículas y polímeros nanoestructurados [3-5]. Los sólidos monolíticos se han empleado con excelentes resultados como fases estacionarias en técnicas de separación debido a las excepcionales propiedades que les confiere su estructura continua, porosa y homogénea [6, 7]. Además, el proceso de fabricación es relativamente simple. En este contexto, la posibilidad de incorporar micro y nanomateriales permite combinar su elevada superficie específica con la alta porosidad y variabilidad funcional de los materiales monolíticos, favoreciendo la interacción con un determinado tipo de analitos [8].Teniendo en cuenta lo anteriormente expuesto, la Tesis Doctoral ha tenido como objetivo general la evaluación del potencial de los sólidos monolíticos modificados con nanoestructuras de carbono como material sorbente en técnicas de microextracción en fase sólida, culminando con el desarrollo de estructuras monolíticas formadas únicamente por nanopartículas. En concreto, se han llevado a cabo diferentes síntesis y estrategias para incorporar las nanopartículas en la matriz polimérica y, se han evaluado distintos formatos de microextracción para la resolución de problemas medioambientales, clínicos y/o de alimentos. Por último, se ha extendido el uso de estos materiales híbridos al ámbito de las separaciones cromatográficas. 2. Contenido de la investigación De acuerdo con el objetivo general, surgen diferentes objetivos específicos que se presentan a continuación: • Estudio bibliográfico como primera toma de contacto con el campo en el que se desarrolla la investigación. Esto se ha materializado en la publicación de una revisión crítica que constituye la Introducción de esta Tesis Doctoral. • Estudio de los procesos de inclusión de las nanopartículas en la matriz polimérica. Así, se estudiarán diferentes estrategias de introducción de las nanopartículas, tales como anclaje químico y fotoquímico a la superficie del polímero, así como atrapamiento de las nanopartículas en la estructura monolítica, que son ampliamente discutidas en el Bloque I. • Evaluación de diferentes formatos de microextracción, tal como se muestra en el Bloque II de esta Memoria. • Desarrollo de nuevas estrategias de síntesis que permitan obtener estructuras monolíticas formadas exclusivamente por nanopartículas de carbono. Esta investigación se recoge en el Bloque III. • Caracterización de los sólidos sintetizados mediante diversas técnicas instrumentales. Esto se ha llevado a cabo a lo largo de la Tesis Doctoral. • Aplicación de las unidades de extracción desarrolladas a la resolución de problemas medioambientales, clínicos y/o de alimentos, de manera transversal en el conjunto de publicaciones de esta Memoria. • Utilización de los sólidos sintetizados como fases estacionarias en separaciones cromatográficas, tal como se muestra en el Capítulo 2 de esta Memoria. 3. Conclusión El objetivo general y los objetivos específicos planteados en la presente Tesis Doctoral se han alcanzado con éxito. De este modo, se ha llevado a cabo la síntesis de nuevos materiales sorbentes que combinan polímeros monolíticos con nanopartículas de carbono, los cuales se han empleado como sorbentes en distintas técnicas de microextracción en fase sólida. Además, se ha realizado la caracterización de dichos materiales mediante técnicas tanto espectroscópicas como microscópicas. Las unidades de microextracción desarrolladas se han aplicado a la resolución de problemas en los ámbitos medioambientales, clínico y/o de alimentos

Efficiency and Sustainability of the Distributed Renewable Hybrid Power Systems Based on the Energy Internet, Blockchain Technology and Smart Contracts

The climate changes that are visible today are a challenge for the global research community. In this context, renewable energy sources, fuel cell systems, and other energy generating sources must be optimally combined and connected to the grid system using advanced energy transaction methods. As this book presents the latest solutions in the implementation of fuel cell and renewable energy in mobile and stationary applications such as hybrid and microgrid power systems based on energy internet, blockchain technology, and smart contracts, we hope that they are of interest to readers working in the related fields mentioned above

Bioinformatics

This book is divided into different research areas relevant in Bioinformatics such as biological networks, next generation sequencing, high performance computing, molecular modeling, structural bioinformatics, molecular modeling and intelligent data analysis. Each book section introduces the basic concepts and then explains its application to problems of great relevance, so both novice and expert readers can benefit from the information and research works presented here

Evaluation et réduction des risques sismiques liés à la liquéfaction : modélisation numérique de leurs effets dans l’ISS

Strong ground motions can trigger soil liquefaction that will alter the propagating signal and induce ground failure. Important damage in structures and lifelines has been evidenced after recent earthquakes such as Christchurch, New Zealand and Tohoku, Japanin 2011. Accurate prediction of the structures’ seismic risk requires a careful modeling of the nonlinear behavior of soil-structure interaction (SSI) systems. In general, seismic risk analysisis described as the convolution between the natural hazard and the vulnerability of the system. This thesis arises as a contribution to the numerical modeling of liquefaction evaluation and mitigation.For this purpose, the finite element method (FEM) in time domain is used as numerical tool. The main numerical model consists of are inforced concrete building with a shallow rigid foundation standing on saturated cohesionless soil. As the initial step on the seismic risk analysis, the first part of the thesis is consecrated to the characterization of the soil behavior and its constitutive modeling. Later on, some results of the model’s validation witha real site for the 1D wave propagation in dry conditions are presented. These are issued from the participation in the international benchmark PRENOLIN and concern the PARI site Sendaiin Japan. Even though very few laboratory and in-situ data were available, the model responses well with the recordings for the blind prediction. The second part, concerns the numerical modeling of coupling excess pore pressure (Δpw) and soil deformation. The effects were evaluated on the ground motion and on the structure’s settlement and performance. This part contains material from an article published in Acta Geotechnica (Montoya-Noguera andLopez-Caballero, 2015). The applicability of the models was found to depend on both the liquefaction level and the SSI effects.In the last part, an innovative method is proposed to model spatial variability added to the deposit due to soil improvement techniques used to strengthen soft soils and mitigate liquefaction. Innovative treatment processes such as bentonite permeations and biogrouting,among others have recently emerged.However, there remains some uncertainties concerning the degree of spatial variability introduced in the design and its effect of the system’s performance.This added variability can differ significantly from the inherent or natural variability thus, in this thesis, it is modeled by coupling FEM with a binary random field. The efficiency in improving the soil behavior related to the effectiveness of the method measured by the amount of soil changed was analyzed. Two cases were studied: the bearing capacity of a shallow foundation under cohesive soil and the liquefaction-induced settlement of a structure under cohesionless loose soil. The latter, in part, contains material published in GeoRisk journal (Montoya-Noguera and Lopez-Caballero, 2015). Due to the interaction between the two soils, an important variability is evidenced in the response. Additionally, traditional and advanced homogenization theories were used to predict the relation between the average efficiency and effectiveness. Because of the nonlinear soil behavior, the traditional theories fail to predict the response while some advanced theories which include the percolation theory may provide a good estimate. Concerning the effect of added spatial variability on soil liquefaction, different input motions were tested and the response of the whole was found to depend on the ratio of PHV and PHA of the input motion.La liquéfaction des sols qui est déclenchée par des mouvements sismiques forts peut modifier la réponse d’un site. Ceci occasionne des dégâts importants dans les structures comme a été mis en évidence lors des tremblements de terre récents tels que celui de Christchurch, Nouvelle-Zélande et du Tohoku, Japon. L’évaluation du risque sismique des structures nécessite une modélisation robuste du comportement non linéaire de sols et de la prise en compte de l’interaction sol-structure (ISS). En général, le risque sismique est décrit comme la convolution entre l’aléa et la vulnérabilité du système. Cette thèse se pose comme une contribution à l’étude, via une modélisation numérique, de l’apparition de la liquéfaction et à l’utilisation des méthodes pour réduire les dommages induits.A cet effet, la méthode des éléments finis(FEM) dans le domaine temporel est utilisée comme outil numérique. Le modèle principal est composé d’un bâtiment fondé sur un sable liquéfiable. Comme la première étape de l’analyse du risque sismique, la première partie de cette thèse est consacrée à la caractérisation du comportement du sol et à sa modélisation.Une attention particulière est donnée à la sensibilité du modèle à des paramètres numériques. En suite, le modèle est validé pour le cas d’une propagation des ondes 1D avec les mesures issus du benchmark international PRENOLIN sur un site japonais. D’après la comparaison, le modèle arrive à prédire les enregistrements dans un test en aveugle.La deuxième partie, concerne la prise en compte dans la modélisation numérique du couplage de la surpression interstitielle (Δpw)et de la déformation du sol. Les effets favorables ou défavorables de ce type de modélisation ont été évalués sur le mouvement en surface du sol lors de la propagation des ondes et aussi sur le tassement et la performance sismique de deux structures.Cette partie contient des éléments d’un article publié dans Acta Geotechnica (Montoya-Noguera and Lopez-Caballero, 2016). Il a été trouvé que l’applicabilité du modèle dépend à la fois du niveau de liquéfaction et des effets d’ISS.Dans la dernière partie, une méthode est proposée pour modéliser la variabilité spatiale ajoutée au dépôt de sol dû à l’utilisation des techniques pour diminuer le degré de liquéfaction. Cette variabilité ajoutée peut différer considérablement de la variabilité inhérente ou naturelle. Dans cette thèse, elle sera modélisée par un champ aléatoire binaire.Pour évaluer l’efficience du mélange, la performance du système a été étudiée pour différents niveaux d’efficacité, c’est-à-dire,différentes fractions spatiales en allant de non traitées jusqu’à entièrement traitées. Tout d’abord le modèle binaire a été testé sur un cas simple, tel que la capacité portante d’une fondation superficielle sur un sol cohérent.Après, il a été utilisé dans le modèle de la structure sur le sol liquéfiable. Ce dernier cas,en partie, a été publié dans la revue GeoRisk (Montoya-Noguera and Lopez-Caballero,2015). En raison de l’interaction entre les deux types de sols du mélange, une importante variabilité est mise en évidence dans la réponse de la structure. En outre, des théories classiques et avancées d’homogénéisation ont été utilisées pour prédire la relation entre l’efficience moyenne et l’efficacité. En raison du comportement non linéaire du sol, les théories traditionnelles ne parviennent pas à prédire la réponse alors que certaines théories avancées qui comprennent la théorie de la percolation peuvent fournir une bonne estimation. En ce qui concerne l’effet de la variabilité spatiale ajoutée sur la diminution du tassement de la structure, différents séismes ont été testés et la réponse globale semble dépendre de leur rapport de PHV et PHA