Marital split-up and widowhood in old age: Differential impact on psychological and social well-being

Marital split-up and spousal loss are among the most stressful critical life events. Numerous studies have documented their detrimental effects on well-being, yet the large individual differences in psychological adaptation are still not well understood. Whereas in old age bereavement is normative and can be anticipated, divorce is an “off-time” transition for this age group. In contrast to bereavement which has been amply studied, research on later life divorce is still missing despite the increasing relevance of the topic due to the significant increase of divorces in older age. Based on a modified and extended view of Amato’s divorce-stress-adjustment model (2000), the aim of this contribution is to explore the differential impact of marital split-up and widowhood in older age on psychological (life satisfaction) and social well-being (social loneliness), and the adaptation to these critical life events. Our analyses are based on data gathered in a questionnaire study, which is part of the Swiss National Centre of Competence in Research LIVES. In a first step we compared three groups of individuals aged 60 to 75 years: a sample of 251 persons with a marital split-up (127 women; 123 men), a sample of 270 widowed persons (170 women; 100 men), and a group of 221 continuously married people (110 women; 111 men), which served as control group. In a second step, we investigated the role of socio-demographic variables, intrapersonal and interpersonal resources and variables of the context of loss as predictors for the psychological adaptation to a marital break-up and loss in old age. First results by ANCOVA indicate significant differences with regard to life satisfaction among the three groups, with divorced persons with the lowest scores, followed by the bereaved ones, and the married controls with the highest. Regarding social loneliness, divorced individuals report higher social loneliness than the bereaved group and the married controls (no significant difference between widowed and the married). In both loss groups, financial and intrapersonal resources, as well as the emotional valence of the loss are the most important predictors for the psychological and social adaptation. However, happiness in the past relationship is an important resource regarding the indicators for adaptation for the widowers, but not for individuals with a marital dissolution.

Expression, purification, and structural insights for the human uric acid transporter, GLUT9, using the Xenopus laevis oocytes system.

The urate transporter, GLUT9, is responsible for the basolateral transport of urate in the proximal tubule of human kidneys and in the placenta, playing a central role in uric acid homeostasis. GLUT9 shares the least homology with other members of the glucose transporter family, especially with the glucose transporting members GLUT1-4 and is the only member of the GLUT family to transport urate. The recently published high-resolution structure of XylE, a bacterial D-xylose transporting homologue, yields new insights into the structural foundation of this GLUT family of proteins. While this represents a huge milestone, it is unclear if human GLUT9 can benefit from this advancement through subsequent structural based targeting and mutagenesis. Little progress has been made toward understanding the mechanism of GLUT9 since its discovery in 2000. Before work can begin on resolving the mechanisms of urate transport we must determine methods to express, purify and analyze hGLUT9 using a model system adept in expressing human membrane proteins. Here, we describe the surface expression, purification and isolation of monomeric protein, and functional analysis of recombinant hGLUT9 using the Xenopus laevis oocyte system. In addition, we generated a new homology-based high-resolution model of hGLUT9 from the XylE crystal structure and utilized our purified protein to generate a low-resolution single particle reconstruction. Interestingly, we demonstrate that the functional protein extracted from the Xenopus system fits well with the homology-based model allowing us to generate the predicted urate-binding pocket and pave a path for subsequent mutagenesis and structure-function studies.

Muon reconstruction efficiency and momentum resolution of the ATLAS experiment in proton-proton collisions at √s = 7 TeV in 2010

This paper presents a study of the performance of the muon reconstruction in the analysis of proton–proton collisions at √s = 7TeV at theLHC, recorded by the ATLAS detector in 2010. This performance is described in terms of reconstruction and isolation efficiencies and momentum resolutions for different classes of reconstructed muons. The results are obtained from an analysis of J/ψ meson and Z boson decays to dimuons, reconstructed from a data sample corresponding to an integrated luminosity of 40 pb−1. The measured performance is compared to Monte Carlo predictions and deviations from the predicted performance are discussed.

Marital breakup in later adulthood and self-rated health: a cross-sectional survey in Switzerland

This research examines the impact of relationship status on self-rated health (SRH) by taking into account intrapersonal and social resources. Data stem from a Swiss-based survey of 1355 participants aged 40-65 years. Three groups are compared: continuously married (n = 399), single divorcees (n = 532) and repartnered divorcees (n = 424). Linear regression models are used to examine the predictive role of relationship status on SRH and to investigate the moderating role of intrapersonal and social resources on SRH. Single divorcees show the lowest SRH scores, whereas their repartnered counterparts reported scores comparable to the continuously married – even after controlling for socio-demographic and economic variables. Although single divorcees reported higher levels of loneliness and agreeableness in addition to lower levels of resilience when compared with the other groups, none of these variables had a significant modification effect on SRH. Our results underscore the positive effect of relationship status on SRH, and contribute new insights on the impact of later-life divorce. Given the growing number of divorcees, related public health challenges are likely to increase.

Marital stability, satisfaction and well-being in old age: Variability and continuity in long-term continuously married older persons

Objectives: Recent research shows that the well-documented positive effects of marital stability on well-being and health outcomes are conditional upon the quality of marriage. To date, few studies have explored the relationship between marital satisfaction, well-being and health among very long-term married individuals. This study aims at identifying groups of long-term married persons with respect to marital satisfaction and comparing them longitudinally concerning their well-being outcomes, marital stressors, personality and socio-demographic variables. Method: Data are derived from a survey (data collection 2012 and 2014) with 374 continuously married individuals at wave 1 (mean age: 74.2 years, length of marriage: 49.2 years) and 252 at wave 2. Cluster analyses were performed comparing the clusters with regard to various well-being outcomes. The predictive power of cluster affiliation and various predictors at wave 1 on well-being outcomes at wave 2 was tested using regression analyses. Results: Two groups were identified, one happily the other unhappily married, with the happily married scoring higher on all well-being and health outcomes. Regression analyses revealed that group affiliation at wave 1 was not any longer predictive of health, emotional loneliness and hopelessness two years later, when taking into account socio-demographic variables, psychological resilience and marital strain, whereas it remained an important predictor of life satisfaction and social loneliness. Conclusion: Marital satisfaction is associated with health and well-being in older couples over time, whereas psychological resilience and marital strain are major predictors explaining the variance of these outcomes.

Marital breakup in later adulthood and self-rated health: a cross-sectional survey in Switzerland

Objectives This research examines the impact of relationship status on self-rated health (SRH) by taking into account intrapersonal and social resources. Methods Data stem from a Swiss-based survey of 1355 participants aged 40–65 years. Three groups are compared: continuously married (n = 399), single divorcees (n = 532) and repartnered divorcees (n = 424). Linear regression models are used to examine the predictive role of relationship status on SRH and to investigate the moderating role of intrapersonal and social resources on SRH. Results Single divorcees show the lowest SRH scores, whereas their repartnered counterparts reported scores comparable to the continuously married—even after controlling for socio-demographic and economic variables. Although single divorcees reported higher levels of loneliness and agreeableness in addition to lower levels of resilience when compared with the other groups, none of these variables had a significant moderation effect on SRH. Conclusions Our results underscore the positive effect of relationship status on SRH, and contribute new insights on the impact of later-life divorce. Given the growing number of divorcees, related public health challenges are likely to increase.

Psychological adaptation to spousal bereavement in old age. The role of trait resilience, marital history, and context of death

This research examined the effect of marital status and gender on various indicators of psychological adaptation, namely depressive symptoms, loneliness, and life satisfaction. It further explores the role of trait resilience, marital history, and context of death for predicting These outcomes in bereaved individuals. Four hundred eighty widowed individuals aged between 60 and 89 were compared with 759 married peers. Main effects were found for marital status and gender for all indicators. The regression analyses illustrate the multifaceted structure of psychological adaptation. Trait resilience is a key factor in adapting to spousal bereavement, whereas marital history and the context are secondary.

Genetic diversity and differentiation follow secondary succession in a multi-species study on woody plants from subtropical China

Aims: Species diversity and genetic diversity may be affected in parallel by similar environmental drivers. However, genetic diversity may also be affected independently by habitat characteristics. We aim at disentangling relationships between genetic diversity, species diversity and habitat characteristics of woody species in subtropical forest. Methods: We studied 11 dominant tree and shrub species in 27 plots in Gutianshan, China, and assessed their genetic diversity (Ar) and population differentiation (F’ST) with microsatellite markers. We tested if Ar and population specific F’ST were correlated to local species diversity and plot characteristics. Multi-model inference and model averaging were used to determine the relative importance of each predictor. Additionally we tested for isolation-by-distance and isolation-by-elevation by regressing pairwise F’ST against pairwise spatial and elevational distances. Important findings: Genetic diversity was not related to species diversity for any of the study species. Thus, our results do not support joint effects of habitat characteristics on these two levels of biodiversity. Instead, genetic diversity in two understory shrubs, Rhododendron simsii and Vaccinium carlesii, was affected by plot age with decreasing genetic diversity in successionally older plots. Population differentiation increased with plot age in Rhododendron simsii and Lithocarpus glaber. This shows that succession can reduce genetic diversity within, and increase genetic diversity between populations. Furthermore, we found four cases of isolation-by-distance and two cases of isolation-by-elevation. The former indicates inefficient pollen and seed dispersal by animals whereas the latter might be due to phenological asynchronies. These patterns indicate that succession can affect genetic diversity without parallel effects on species diversity and that gene flow in a continuous subtropical forest can be restricted even at a local scale.

Trust-ware: A Methodology to Analyze, Design, and Secure Trust and Reputation Systems

Entendemos por inteligencia colectiva una forma de inteligencia que surge de la colaboración y la participación de varios individuos o, siendo más estrictos, varias entidades. En base a esta sencilla definición podemos observar que este concepto es campo de estudio de las más diversas disciplinas como pueden ser la sociología, las tecnologías de la información o la biología, atendiendo cada una de ellas a un tipo de entidades diferentes: seres humanos, elementos de computación o animales. Como elemento común podríamos indicar que la inteligencia colectiva ha tenido como objetivo el ser capaz de fomentar una inteligencia de grupo que supere a la inteligencia individual de las entidades que lo forman a través de mecanismos de coordinación, cooperación, competencia, integración, diferenciación, etc. Sin embargo, aunque históricamente la inteligencia colectiva se ha podido desarrollar de forma paralela e independiente en las distintas disciplinas que la tratan, en la actualidad, los avances en las tecnologías de la información han provocado que esto ya no sea suficiente. Hoy en día seres humanos y máquinas a través de todo tipo de redes de comunicación e interfaces, conviven en un entorno en el que la inteligencia colectiva ha cobrado una nueva dimensión: ya no sólo puede intentar obtener un comportamiento superior al de sus entidades constituyentes sino que ahora, además, estas inteligencias individuales son completamente diferentes unas de otras y aparece por lo tanto el doble reto de ser capaces de gestionar esta gran heterogeneidad y al mismo tiempo ser capaces de obtener comportamientos aún más inteligentes gracias a las sinergias que los distintos tipos de inteligencias pueden generar. Dentro de las áreas de trabajo de la inteligencia colectiva existen varios campos abiertos en los que siempre se intenta obtener unas prestaciones superiores a las de los individuos. Por ejemplo: consciencia colectiva, memoria colectiva o sabiduría colectiva. Entre todos estos campos nosotros nos centraremos en uno que tiene presencia en la práctica totalidad de posibles comportamientos inteligentes: la toma de decisiones. El campo de estudio de la toma de decisiones es realmente amplio y dentro del mismo la evolución ha sido completamente paralela a la que citábamos anteriormente en referencia a la inteligencia colectiva. En primer lugar se centró en el individuo como entidad decisoria para posteriormente desarrollarse desde un punto de vista social, institucional, etc. La primera fase dentro del estudio de la toma de decisiones se basó en la utilización de paradigmas muy sencillos: análisis de ventajas e inconvenientes, priorización basada en la maximización de algún parámetro del resultado, capacidad para satisfacer los requisitos de forma mínima por parte de las alternativas, consultas a expertos o entidades autorizadas o incluso el azar. Sin embargo, al igual que el paso del estudio del individuo al grupo supone una nueva dimensión dentro la inteligencia colectiva la toma de decisiones colectiva supone un nuevo reto en todas las disciplinas relacionadas. Además, dentro de la decisión colectiva aparecen dos nuevos frentes: los sistemas de decisión centralizados y descentralizados. En el presente proyecto de tesis nos centraremos en este segundo, que es el que supone una mayor atractivo tanto por las posibilidades de generar nuevo conocimiento y trabajar con problemas abiertos actualmente así como en lo que respecta a la aplicabilidad de los resultados que puedan obtenerse. Ya por último, dentro del campo de los sistemas de decisión descentralizados existen varios mecanismos fundamentales que dan lugar a distintas aproximaciones a la problemática propia de este campo. Por ejemplo el liderazgo, la imitación, la prescripción o el miedo. Nosotros nos centraremos en uno de los más multidisciplinares y con mayor capacidad de aplicación en todo tipo de disciplinas y que, históricamente, ha demostrado que puede dar lugar a prestaciones muy superiores a otros tipos de mecanismos de decisión descentralizados: la confianza y la reputación. Resumidamente podríamos indicar que confianza es la creencia por parte de una entidad que otra va a realizar una determinada actividad de una forma concreta. En principio es algo subjetivo, ya que la confianza de dos entidades diferentes sobre una tercera no tiene porqué ser la misma. Por otro lado, la reputación es la idea colectiva (o evaluación social) que distintas entidades de un sistema tiene sobre otra entidad del mismo en lo que respecta a un determinado criterio. Es por tanto una información de carácter colectivo pero única dentro de un sistema, no asociada a cada una de las entidades del sistema sino por igual a todas ellas. En estas dos sencillas definiciones se basan la inmensa mayoría de sistemas colectivos. De hecho muchas disertaciones indican que ningún tipo de organización podría ser viable de no ser por la existencia y la utilización de los conceptos de confianza y reputación. A partir de ahora, a todo sistema que utilice de una u otra forma estos conceptos lo denominaremos como sistema de confianza y reputación (o TRS, Trust and Reputation System). Sin embargo, aunque los TRS son uno de los aspectos de nuestras vidas más cotidianos y con un mayor campo de aplicación, el conocimiento que existe actualmente sobre ellos no podría ser más disperso. Existen un gran número de trabajos científicos en todo tipo de áreas de conocimiento: filosofía, psicología, sociología, economía, política, tecnologías de la información, etc. Pero el principal problema es que no existe una visión completa de la confianza y reputación en su sentido más amplio. Cada disciplina focaliza sus estudios en unos aspectos u otros dentro de los TRS, pero ninguna de ellas trata de explotar el conocimiento generado en el resto para mejorar sus prestaciones en su campo de aplicación concreto. Aspectos muy detallados en algunas áreas de conocimiento son completamente obviados por otras, o incluso aspectos tratados por distintas disciplinas, al ser estudiados desde distintos puntos de vista arrojan resultados complementarios que, sin embargo, no son aprovechados fuera de dichas áreas de conocimiento. Esto nos lleva a una dispersión de conocimiento muy elevada y a una falta de reutilización de metodologías, políticas de actuación y técnicas de una disciplina a otra. Debido su vital importancia, esta alta dispersión de conocimiento se trata de uno de los principales problemas que se pretenden resolver con el presente trabajo de tesis. Por otro lado, cuando se trabaja con TRS, todos los aspectos relacionados con la seguridad están muy presentes ya que muy este es un tema vital dentro del campo de la toma de decisiones. Además también es habitual que los TRS se utilicen para desempeñar responsabilidades que aportan algún tipo de funcionalidad relacionada con el mundo de la seguridad. Por último no podemos olvidar que el acto de confiar está indefectiblemente unido al de delegar una determinada responsabilidad, y que al tratar estos conceptos siempre aparece la idea de riesgo, riesgo de que las expectativas generadas por el acto de la delegación no se cumplan o se cumplan de forma diferente. Podemos ver por lo tanto que cualquier sistema que utiliza la confianza para mejorar o posibilitar su funcionamiento, por su propia naturaleza, es especialmente vulnerable si las premisas en las que se basa son atacadas. En este sentido podemos comprobar (tal y como analizaremos en más detalle a lo largo del presente documento) que las aproximaciones que realizan las distintas disciplinas que tratan la violación de los sistemas de confianza es de lo más variado. únicamente dentro del área de las tecnologías de la información se ha intentado utilizar alguno de los enfoques de otras disciplinas de cara a afrontar problemas relacionados con la seguridad de TRS. Sin embargo se trata de una aproximación incompleta y, normalmente, realizada para cumplir requisitos de aplicaciones concretas y no con la idea de afianzar una base de conocimiento más general y reutilizable en otros entornos. Con todo esto en cuenta, podemos resumir contribuciones del presente trabajo de tesis en las siguientes. • La realización de un completo análisis del estado del arte dentro del mundo de la confianza y la reputación que nos permite comparar las ventajas e inconvenientes de las diferentes aproximación que se realizan a estos conceptos en distintas áreas de conocimiento. • La definición de una arquitectura de referencia para TRS que contempla todas las entidades y procesos que intervienen en este tipo de sistemas. • La definición de un marco de referencia para analizar la seguridad de TRS. Esto implica tanto identificar los principales activos de un TRS en lo que respecta a la seguridad, así como el crear una tipología de posibles ataques y contramedidas en base a dichos activos. • La propuesta de una metodología para el análisis, el diseño, el aseguramiento y el despliegue de un TRS en entornos reales. Adicionalmente se exponen los principales tipos de aplicaciones que pueden obtenerse de los TRS y los medios para maximizar sus prestaciones en cada una de ellas. • La generación de un software que permite simular cualquier tipo de TRS en base a la arquitectura propuesta previamente. Esto permite evaluar las prestaciones de un TRS bajo una determinada configuración en un entorno controlado previamente a su despliegue en un entorno real. Igualmente es de gran utilidad para evaluar la resistencia a distintos tipos de ataques o mal-funcionamientos del sistema. Además de las contribuciones realizadas directamente en el campo de los TRS, hemos realizado aportaciones originales a distintas áreas de conocimiento gracias a la aplicación de las metodologías de análisis y diseño citadas con anterioridad. • Detección de anomalías térmicas en Data Centers. Hemos implementado con éxito un sistema de deteción de anomalías térmicas basado en un TRS. Comparamos la detección de prestaciones de algoritmos de tipo Self-Organized Maps (SOM) y Growing Neural Gas (GNG). Mostramos como SOM ofrece mejores resultados para anomalías en los sistemas de refrigeración de la sala mientras que GNG es una opción más adecuada debido a sus tasas de detección y aislamiento para casos de anomalías provocadas por una carga de trabajo excesiva. • Mejora de las prestaciones de recolección de un sistema basado en swarm computing y odometría social. Gracias a la implementación de un TRS conseguimos mejorar las capacidades de coordinación de una red de robots autónomos distribuidos. La principal contribución reside en el análisis y la validación de las mejoras increméntales que pueden conseguirse con la utilización apropiada de la información existente en el sistema y que puede ser relevante desde el punto de vista de un TRS, y con la implementación de algoritmos de cálculo de confianza basados en dicha información. • Mejora de la seguridad de Wireless Mesh Networks contra ataques contra la integridad, la confidencialidad o la disponibilidad de los datos y / o comunicaciones soportadas por dichas redes. • Mejora de la seguridad de Wireless Sensor Networks contra ataques avanzamos, como insider attacks, ataques desconocidos, etc. Gracias a las metodologías presentadas implementamos contramedidas contra este tipo de ataques en entornos complejos. En base a los experimentos realizados, hemos demostrado que nuestra aproximación es capaz de detectar y confinar varios tipos de ataques que afectan a los protocoles esenciales de la red. La propuesta ofrece unas velocidades de detección muy altas así como demuestra que la inclusión de estos mecanismos de actuación temprana incrementa significativamente el esfuerzo que un atacante tiene que introducir para comprometer la red. Finalmente podríamos concluir que el presente trabajo de tesis supone la generación de un conocimiento útil y aplicable a entornos reales, que nos permite la maximización de las prestaciones resultantes de la utilización de TRS en cualquier tipo de campo de aplicación. De esta forma cubrimos la principal carencia existente actualmente en este campo, que es la falta de una base de conocimiento común y agregada y la inexistencia de una metodología para el desarrollo de TRS que nos permita analizar, diseñar, asegurar y desplegar TRS de una forma sistemática y no artesanal y ad-hoc como se hace en la actualidad. ABSTRACT By collective intelligence we understand a form of intelligence that emerges from the collaboration and competition of many individuals, or strictly speaking, many entities. Based on this simple definition, we can see how this concept is the field of study of a wide range of disciplines, such as sociology, information science or biology, each of them focused in different kinds of entities: human beings, computational resources, or animals. As a common factor, we can point that collective intelligence has always had the goal of being able of promoting a group intelligence that overcomes the individual intelligence of the basic entities that constitute it. This can be accomplished through different mechanisms such as coordination, cooperation, competence, integration, differentiation, etc. Collective intelligence has historically been developed in a parallel and independent way among the different disciplines that deal with it. However, this is not enough anymore due to the advances in information technologies. Nowadays, human beings and machines coexist in environments where collective intelligence has taken a new dimension: we yet have to achieve a better collective behavior than the individual one, but now we also have to deal with completely different kinds of individual intelligences. Therefore, we have a double goal: being able to deal with this heterogeneity and being able to get even more intelligent behaviors thanks to the synergies that the different kinds of intelligence can generate. Within the areas of collective intelligence there are several open topics where they always try to get better performances from groups than from the individuals. For example: collective consciousness, collective memory, or collective wisdom. Among all these topics we will focus on collective decision making, that has influence in most of the collective intelligent behaviors. The field of study of decision making is really wide, and its evolution has been completely parallel to the aforementioned collective intelligence. Firstly, it was focused on the individual as the main decision-making entity, but later it became involved in studying social and institutional groups as basic decision-making entities. The first studies within the decision-making discipline were based on simple paradigms, such as pros and cons analysis, criteria prioritization, fulfillment, following orders, or even chance. However, in the same way that studying the community instead of the individual meant a paradigm shift within collective intelligence, collective decision-making means a new challenge for all the related disciplines. Besides, two new main topics come up when dealing with collective decision-making: centralized and decentralized decision-making systems. In this thesis project we focus in the second one, because it is the most interesting based on the opportunities to generate new knowledge and deal with open issues in this area, as well as these results can be put into practice in a wider set of real-life environments. Finally, within the decentralized collective decision-making systems discipline, there are several basic mechanisms that lead to different approaches to the specific problems of this field, for example: leadership, imitation, prescription, or fear. We will focus on trust and reputation. They are one of the most multidisciplinary concepts and with more potential for applying them in every kind of environments. Besides, they have historically shown that they can generate better performance than other decentralized decision-making mechanisms. Shortly, we say trust is the belief of one entity that the outcome of other entities’ actions is going to be in a specific way. It is a subjective concept because the trust of two different entities in another one does not have to be the same. Reputation is the collective idea (or social evaluation) that a group of entities within a system have about another entity based on a specific criterion. Thus, it is a collective concept in its origin. It is important to say that the behavior of most of the collective systems are based on these two simple definitions. In fact, a lot of articles and essays describe how any organization would not be viable if the ideas of trust and reputation did not exist. From now on, we call Trust an Reputation System (TRS) to any kind of system that uses these concepts. Even though TRSs are one of the most common everyday aspects in our lives, the existing knowledge about them could not be more dispersed. There are thousands of scientific works in every field of study related to trust and reputation: philosophy, psychology, sociology, economics, politics, information sciences, etc. But the main issue is that a comprehensive vision of trust and reputation for all these disciplines does not exist. Every discipline focuses its studies on a specific set of topics but none of them tries to take advantage of the knowledge generated in the other disciplines to improve its behavior or performance. Detailed topics in some fields are completely obviated in others, and even though the study of some topics within several disciplines produces complementary results, these results are not used outside the discipline where they were generated. This leads us to a very high knowledge dispersion and to a lack in the reuse of methodologies, policies and techniques among disciplines. Due to its great importance, this high dispersion of trust and reputation knowledge is one of the main problems this thesis contributes to solve. When we work with TRSs, all the aspects related to security are a constant since it is a vital aspect within the decision-making systems. Besides, TRS are often used to perform some responsibilities related to security. Finally, we cannot forget that the act of trusting is invariably attached to the act of delegating a specific responsibility and, when we deal with these concepts, the idea of risk is always present. This refers to the risk of generated expectations not being accomplished or being accomplished in a different way we anticipated. Thus, we can see that any system using trust to improve or enable its behavior, because of its own nature, is especially vulnerable if the premises it is based on are attacked. Related to this topic, we can see that the approaches of the different disciplines that study attacks of trust and reputation are very diverse. Some attempts of using approaches of other disciplines have been made within the information science area of knowledge, but these approaches are usually incomplete, not systematic and oriented to achieve specific requirements of specific applications. They never try to consolidate a common base of knowledge that could be reusable in other context. Based on all these ideas, this work makes the following direct contributions to the field of TRS: • The compilation of the most relevant existing knowledge related to trust and reputation management systems focusing on their advantages and disadvantages. • We define a generic architecture for TRS, identifying the main entities and processes involved. • We define a generic security framework for TRS. We identify the main security assets and propose a complete taxonomy of attacks for TRS. • We propose and validate a methodology to analyze, design, secure and deploy TRS in real-life environments. Additionally we identify the principal kind of applications we can implement with TRS and how TRS can provide a specific functionality. • We develop a software component to validate and optimize the behavior of a TRS in order to achieve a specific functionality or performance. In addition to the contributions made directly to the field of the TRS, we have made original contributions to different areas of knowledge thanks to the application of the analysis, design and security methodologies previously presented: • Detection of thermal anomalies in Data Centers. Thanks to the application of the TRS analysis and design methodologies, we successfully implemented a thermal anomaly detection system based on a TRS.We compare the detection performance of Self-Organized- Maps and Growing Neural Gas algorithms. We show how SOM provides better results for Computer Room Air Conditioning anomaly detection, yielding detection rates of 100%, in training data with malfunctioning sensors. We also show that GNG yields better detection and isolation rates for workload anomaly detection, reducing the false positive rate when compared to SOM. • Improving the performance of a harvesting system based on swarm computing and social odometry. Through the implementation of a TRS, we achieved to improve the ability of coordinating a distributed network of autonomous robots. The main contribution lies in the analysis and validation of the incremental improvements that can be achieved with proper use information that exist in the system and that are relevant for the TRS, and the implementation of the appropriated trust algorithms based on such information. • Improving Wireless Mesh Networks security against attacks against the integrity, confidentiality or availability of data and communications supported by these networks. Thanks to the implementation of a TRS we improved the detection time rate against these kind of attacks and we limited their potential impact over the system. • We improved the security of Wireless Sensor Networks against advanced attacks, such as insider attacks, unknown attacks, etc. Thanks to the TRS analysis and design methodologies previously described, we implemented countermeasures against such attacks in a complex environment. In our experiments we have demonstrated that our system is capable of detecting and confining various attacks that affect the core network protocols. We have also demonstrated that our approach is capable of rapid attack detection. Also, it has been proven that the inclusion of the proposed detection mechanisms significantly increases the effort the attacker has to introduce in order to compromise the network. Finally we can conclude that, to all intents and purposes, this thesis offers a useful and applicable knowledge in real-life environments that allows us to maximize the performance of any system based on a TRS. Thus, we deal with the main deficiency of this discipline: the lack of a common and complete base of knowledge and the lack of a methodology for the development of TRS that allow us to analyze, design, secure and deploy TRS in a systematic way.

Viviendas productivas

El presente trabajo recoge los resultados de una investigación sobre la «vivienda productiva», es decir, de la casa como lugar de trabajo. Dicha investigación se ha ocupado de explorar cómo influyen las cotidianeidades doméstico-laborales actuales —junto con sus arquitecturas y los urbanismos que estas generan— en la sociedad, en especial en temas sociales centrales como la construcción de las subjetividades, y de una vida en comunidad. Asimismo, explora cómo podrían influir en un futuro. La hipótesis sobre la que se trabaja, y que finalmente se intenta demostrar, consiste en que, en la territorialidad múltiple de lo laboral, la vivienda, como plataforma doméstica multiusos, productiva y reproductiva de la que muchas personas disponen, desempeña un papel nodal, y es posible que en el futuro su papel sea aún más importante y más visible. La vivienda productiva funciona como una infraestructura urbana desde la cual se construyen diferentes tipos de bienes materiales e inmateriales, pero sobre todo formas de relación, sociales y productivas con otros, además de imaginarios y afectos. La vivienda como infraestructura productiva y reproductiva es tanto «fábrica fundamental de lo social», como nos enseña Silvia Federici, como «fábrica de lo urbano». El trabajo en casa, como parte de diferentes dinámicas «dispersas» del trabajo que se dan en la actualidad, presenta tanto problemáticas y desafíos importantes, como capitales y posibilidades sociales. Por un lado, puede facilitar una absorción de tipo «24/7» vinculada a las lógicas de producción dispersa y consumo dominantes además de la que se da por las dinámicas patriarcales tradicionales, y en múltiples casos situaciones de evidente asimetría y de explotación laboral. También puede propiciar situaciones socialmente extendidas o impuestas de soledad y aislamiento. Sin embargo, está asimismo vinculado al surgimiento de espacios de experimentación tanto en soledad como en compañía, de cooperación y de intercambio, además de a la evidente posibilidad de construir rutinas propias y, por tanto, una subjetividad laboral propia. Por otro lado, frente a la idea general y homogénea del trabajador casero como un sujeto mayoritariamente aislado de su entorno, las jornadas de trabajo de los trabajadores caseros estudiados presentan una gran diversidad. Estas pueden conllevar aislamiento y exclusión, así como acompañar diferentes formas de construcción de una ciudadanía activa, tanto en solitario, como mediante formas de participación activa en la construcción de una vida en comunidad. En esta investigación se analizan, pues, desafíos y oportunidades de estas espacialidades del trabajo y, a través de este análisis, se indaga en el papel de los marcos físicos, organizativos y simbólicos actuales para la vivienda y para la ciudad pensada desde los trabajadores caseros. Al mismo tiempo se exploran nuevos tipos de vivienda y urbanismos que puedan quizás acompañar procesos sociales de inclusión, así como de emancipación, cooperación e intercambio y, en general, nuevas formas de vecindad y bienestar compartido en los ámbitos doméstico-productivos. Metodológicamente, las singularidades presentes en las realidades estudiadas invitan además a explorar protocolos de análisis, métodos de diseño, de gestión y gobierno que, desde lo micro, puedan dialogar con lo cotidiano y sus singularidades. Diego Barajas, autor de la tesis, es arquitecto dedicado a la práctica, a la investigación y la docencia. Su trabajo se focaliza en explorar el carácter mediador de la arquitectura frente a lo cotidiano y sus microrrealidades. Es profesor de proyectos de urbanismo en la IE School of Architecture y es miembro de Husos, una plataforma de investigación y diseño orientada a la innovación en arquitectura y urbanismo, con sede en Madrid. Es el autor del libro Dispersion, A Study of Global Mobility and the Dynamics of a Fictional Urbanism (Episode Publishers, Róterdam, 2003). Sus trabajos teóricos y de investigación han aparecido en libros y revistas internacionales tales como The Domestic and The Foreign in Architecture (010 Publishers, 2008), Public Spheres, a Europan Discussion (Europan9, 2007), Photoespaña 05 (La Fábrica, Madrid, 2005), Domus, Volume, Abitare, Architese, Plot, y Summa+. Su trabajo se ha expuesto en la Bienal de Venecia (selección principal), la Bienal de Róterdam, la Fundación Tapies, Photoespaña, entre otros y es parte de la colección permanente del FRAC Centre en Orleans y del Historisch Museum de Róterdam entre otros. Antes de estudiar en Róterdam, se gradúa con Honores en la Universidad de los Andes en 1999 y su tesis de grado de arquitectura recibe la máxima distinción como proyecto de Grado Meritorio. ABSTRACT The present study records an investigation into the «productive house», or the home as a workplace. This investigation looks at how working from home, its architectures, and the urban dynamics generated around it influence daily life and the construction of society. It also explores what influences home-based work might have in the future, particularly in central themes such as the biopolitical construction of subjectivities and community life. The central hypothesis revolves around the idea that the home, as a multi-use infrastructure that most of us have access to, plays a fundamental role in the contemporary work sphere, due to —or even in spite of— the omnipresence of work in practically every moment and area of our daily lives, and might play a main role in the future. The home functions as a kind of hub from which we create different kinds of material and immaterial goods, but above all relationships with others, both social and productive, as well as imaginaries and affections. The home, as a machine for production and reproduction, is as much a main «factory of the social» as Silvia Federici describes it, as a «factory of the urban». Working from home, as one of several «dispersed» work dynamics that are part of the contemporary world of work, presents as many important problematics and challenges as it does possibilities and social capital. On the one hand, it can contribute to kind of «24/7» absorption linked both to the logistics of the current dispersed production and consumption, and to that of traditional patriarchal dynamics, and in some cases even clearly asymmetrical situations that exploit the workforce. It can also lead to the socially widespread phenomena of isolation and loneliness, at times imposed upon home-based workers. However, by the same token, it is also linked to the growth of experimental spaces of cooperation and exchange, both solitary and in company, as well as the clear possibility of constructing individualised routines and, therefore, a personal laboural subjectivity. On the other hand, contrary to the generalised, homogenous idea of a home-based worker who is mostly isolated from his or her environment, the working days of those we studied went hand in hand with different ways of building subjectivities. This could be as much in exclusion and isolation as through building an active citizenship, at times in solitary and at times actively participating in the construction of communal life. In this investigation, therefore, the challenges and opportunities of the home as workplace have been analysed, and through this analysis we have inquired into the role of current physical, organisational and symbolic frameworks for the home and for the city from the perspective of home workers. At the same time we have explored new types of homes and of town planning that could perhaps accompany social processes of diversity and inclusion as well as emancipation, cooperation and exchange and, in general, new forms of shared welfare in productive domestic environments. Methodologically, the singularities present in the cases studied also invite us to explore protocols of analysis, methods of design, management and government that, from the micro level, could dialogue with the peculiarities of day-to-day life. The author of this thesis, Diego Barajas, is an architect dedicated to practice, investigation and teaching. His work is focussed on exploring the mediating nature of architecture and the built environment in terms of daily life and its microrealities. He is professor of urban projects at the IE School of Architecture and member of Husos, a platform for investigation and town planning based in Madrid. He is the author of the book Dispersion, A Study of Global Mobility and the Dynamics of a Fictional Urbanism (Episode Publishers, Rotterdam, 2003) and his theoretical works and investigations have appeared in books such as The Domestic and The Foreign in Architecture (010 Publishers, 2008), Public Spheres, a Europan Discussion (Europan9, 2007), Photoespaña 05 (La Fábrica, Madrid, 2005), and in international magazines such as Domus, Volume, Abitare, Architese, Plot and Summa+. His work has been exhibited in places such as the Venice Biennial (main selection), the Rotterdam Biennial, the Tapies Foundation and Photoespaña, among others, and forms part of the permanent collection of the FRAC Centre in Orleans and the Historisch Museum of Rotterdam. Before studying in Rotterdam, he graduated with Honours from the University of the Andes in 1999, and his architecture degree thesis received the maximum distinction of Meritorious Graduation Project.

Necessidades sociais de idosos em diferentes contextos de inserção : estudo comparativo na cidade de Samora Correia

Dissertação apresentada para a obtenção do grau de mestre na área de Educação Social e Intervenção Comunitária

REFLEXOS INDIVIDUAIS DO USO PESSOAL E EXCESSIVO DE COMUNICADORES INSTANTÂNEOS NO AMBIENTE DE TRABALHO

A Internet está inserida no cotidiano do indivíduo, e torna-se cada vez mais acessível por meio de diferentes tipos de dispositivos. Com isto, diversos estudos foram realizados com o intuito de avaliar os reflexos do seu uso excessivo na vida pessoal, acadêmica e profissional. Esta dissertação buscou identificar se a perda de concentração e o isolamento social são alguns dos reflexos individuais que o uso pessoal e excessivo de aplicativos de comunicação instantânea podem resultar no ambiente de trabalho. Entre as variáveis selecionadas para avaliar os aspectos do uso excessivo de comunicadores instantâneos tem-se a distração digital, o controle reduzido de impulso, o conforto social e a solidão. Através de uma abordagem de investigação quantitativa, utilizaram-se escalas aplicadas a uma amostra de 283 pessoas. Os dados foram analisados por meio de técnicas estatísticas multivariadas como a Análise Fatorial Exploratória e para auferir a relação entre as variáveis, a Regressão Linear Múltipla. Os resultados deste estudo confirmam que o uso excessivo de comunicadores instantâneos está positivamente relacionado com a perda de concentração, e a variável distração digital exerce uma influência maior do que o controle reduzido de impulso. De acordo com os resultados, não se podem afirmar que a solidão e o conforto social exercem relações com aumento do isolamento social, devido à ausência do relacionamento entre os construtos.

Reciprocal subtraction differential RNA display: An efficient and rapid procedure for isolating differentially expressed gene sequences

A reciprocal subtraction differential RNA display (RSDD) approach has been developed that permits the rapid and efficient identification and cloning of both abundant and rare differentially expressed genes. RSDD comprises reciprocal subtraction of cDNA libraries followed by differential RNA display. The RSDD strategy was applied to analyze the gene expression alterations resulting during cancer progression as adenovirus-transformed rodent cells developed an aggressive transformed state, as documented by elevated anchorage-independence and enhanced in vivo oncogenesis in nude mice. This approach resulted in the identification and cloning of both known and a high proportion (>65%) of unknown sequences, including cDNAs displaying elevated expression as a function of progression (progression-elevated gene) and cDNAs displaying suppressed expression as a function of progression (progression-suppressed gene). Sixteen differentially expressed genes, including five unknown progression-elevated genes and six unknown progression-suppressed genes, have been characterized. The RSDD scheme should find wide application for the effective detection and isolation of differentially expressed genes.

Mapping of contact sites in complex formation between transducin and light-activated rhodopsin by covalent crosslinking: Use of a photoactivatable reagent

Interaction of light-activated rhodopsin with transducin (T) is the first event in visual signal transduction. We use covalent crosslinking approaches to map the contact sites in interaction between the two proteins. Here we use a photoactivatable reagent, N-[(2-pyridyldithio)-ethyl], 4-azido salicylamide. The reagent is attached to the SH group of cytoplasmic monocysteine rhodopsin mutants by a disulfide-exchange reaction with the pyridylthio group, and the derivatized rhodopsin then is complexed with T by illumination at λ >495 nm. Subsequent irradiation of the complex at λ310 nm generates covalent crosslinks between the two proteins. Crosslinking was demonstrated between T and a number of single cysteine rhodopsin mutants. However, sites of crosslinks were investigated in detail only between T and the rhodopsin mutant S240C (cytoplasmic loop V-VI). Crosslinking occurred predominantly with Tα. For identification of the sites of crosslinks in Tα, the strategy used involved: (i) derivatization of all of the free cysteines in the crosslinked proteins with N-ethylmaleimide; (ii) reduction of the disulfide bond linking the two proteins and isolation of all of the Tα species carrying the crosslinked moiety with a free SH group; (iii) adduct formation of the latter with the N-maleimide moiety of the reagent, maleimido-butyryl-biocytin, containing a biotinyl group; (iv) trypsin degradation of the resulting Tα derivatives and isolation of Tα peptides carrying maleimido-butyryl-biocytin by avidin-agarose chromatography; and (v) identification of the isolated peptides by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. We found that crosslinking occurred mainly to two C-terminal peptides in Tα containing the amino acid sequences 310–313 and 342–345.

Gene genealogies and population variation in plants

Early in the development of plant evolutionary biology, genetic drift, fluctuations in population size, and isolation were identified as critical processes that affect the course of evolution in plant species. Attempts to assess these processes in natural populations became possible only with the development of neutral genetic markers in the 1960s. More recently, the application of historically ordered neutral molecular variation (within the conceptual framework of coalescent theory) has allowed a reevaluation of these microevolutionary processes. Gene genealogies trace the evolutionary relationships among haplotypes (alleles) with populations. Processes such as selection, fluctuation in population size, and population substructuring affect the geographical and genealogical relationships among these alleles. Therefore, examination of these genealogical data can provide insights into the evolutionary history of a species. For example, studies of Arabidopsis thaliana have suggested that this species underwent rapid expansion, with populations showing little genetic differentiation. The new discipline of phylogeography examines the distribution of allele genealogies in an explicit geographical context. Phylogeographic studies of plants have documented the recolonization of European tree species from refugia subsequent to Pleistocene glaciation, and such studies have been instructive in understanding the origin and domestication of the crop cassava. Currently, several technical limitations hinder the widespread application of a genealogical approach to plant evolutionary studies. However, as these technical issues are solved, a genealogical approach holds great promise for understanding these previously elusive processes in plant evolution.