2,299 research outputs found

    On the anonymity risk of time-varying user profiles.

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    Websites and applications use personalisation services to profile their users, collect their patterns and activities and eventually use this data to provide tailored suggestions. User preferences and social interactions are therefore aggregated and analysed. Every time a user publishes a new post or creates a link with another entity, either another user, or some online resource, new information is added to the user profile. Exposing private data does not only reveal information about single users’ preferences, increasing their privacy risk, but can expose more about their network that single actors intended. This mechanism is self-evident in social networks where users receive suggestions based on their friends’ activities. We propose an information-theoretic approach to measure the differential update of the anonymity risk of time-varying user profiles. This expresses how privacy is affected when new content is posted and how much third-party services get to know about the users when a new activity is shared. We use actual Facebook data to show how our model can be applied to a real-world scenario.Peer ReviewedPostprint (published version

    On web user tracking of browsing patterns for personalised advertising

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    This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Parallel, Emergent and Distributed Systems on 19/02/2017, available online: http://www.tandfonline.com/doi/abs/10.1080/17445760.2017.1282480On today’s Web, users trade access to their private data for content and services. App and service providers want to know everything they can about their users, in order to improve their product experience. Also, advertising sustains the business model of many websites and applications. Efficient and successful advertising relies on predicting users’ actions and tastes to suggest a range of products to buy. Both service providers and advertisers try to track users’ behaviour across their product network. For application providers this means tracking users’ actions within their platform. For third-party services following users, means being able to track them across different websites and applications. It is well known how, while surfing the Web, users leave traces regarding their identity in the form of activity patterns and unstructured data. These data constitute what is called the user’s online footprint. We analyse how advertising networks build and collect users footprints and how the suggested advertising reacts to changes in the user behaviour.Peer ReviewedPostprint (author's final draft

    Proyecto de comprensión musical: el Rock´n Roll

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    Este Trabajo Fin de Grado se centra en la realización de un proyecto de comprensión en la etapa de Educación Infantil, basado en un tema de gran actualidad e indudables posibilidades didácticas como es el rock´n roll. A la hora de plantearlo, se ha contrastado la información aportada por diversos autores acerca de este tema y se ha diseñado una serie de actividades para llevarlo a cabo dentro del aula.Grado en Educación Infanti

    Diabetic Retinopathy: Two Faces Of The Same Coin

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    We report two contrasting cases of diabetic retinopathy to illustrate vascular and retinal abnormalities in this condition. In the first case, mild diabetic retinopathy is diagnosed in an asymptomatic patient with diabetes mellitus of recent onset. The second patient has severe diabetic retinopathy, causing vision loss as a consequence of poor metabolic control

    On content-based recommendation and user privacy in social-tagging systems

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    Recommendation systems and content filtering approaches based on annotations and ratings, essentially rely on users expressing their preferences and interests through their actions, in order to provide personalised content. This activity, in which users engage collectively has been named social tagging, and it is one of the most popular in which users engage online, and although it has opened new possibilities for application interoperability on the semantic web, it is also posing new privacy threats. It, in fact, consists of describing online or offline resources by using free-text labels (i.e. tags), therefore exposing the user profile and activity to privacy attacks. Users, as a result, may wish to adopt a privacy-enhancing strategy in order not to reveal their interests completely. Tag forgery is a privacy enhancing technology consisting of generating tags for categories or resources that do not reflect the user's actual preferences. By modifying their profile, tag forgery may have a negative impact on the quality of the recommendation system, thus protecting user privacy to a certain extent but at the expenses of utility loss. The impact of tag forgery on content-based recommendation is, therefore, investigated in a real-world application scenario where different forgery strategies are evaluated, and the consequent loss in utility is measured and compared.Peer ReviewedPostprint (author’s final draft

    Consequences of climate change on mental health

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    Treball Final de Grau en Psicologia. Codi: PS1048. Curs: 2020/2021Climate change is the cause of alterations in the climate and the environment, which can cause extreme events such as droughts and floods. Thus, this factor endangers the survival of many species and ecosystems. Furthermore, climate change can be a major threat to the identity of the communities whose way of life is dependent on the environment. For this reason, this bibliographic review focuses on the psychological consequences that climate change has on mental health. The direct impacts of this phenomenon, such as forest fires, or indirect impacts such as repeated exposure to information about changes in the environment, can cause emotional disturbances. Some of these consequences could be anxiety, alterations in mood or psychoterratic syndromes. A risk factor could be a high degree of neuroticism, while a protective factor would be a high level of openness. Therefore, it would be convenient to investigate psychological interventions which would allow us to face it in a more adaptive way. These strategies could be focused on promoting resilience and behavioural commitment in the face of the challenge posed by this phenomenon. Likewise, it would be advisable to develop policies that make it possible to achieve goal number 13 of the UN Sustainable Development Goals, that is, to adopt urgent measures to combat climate change and its effects.El cambio climático es la causa de las alteraciones en el clima y en el medio ambiente, que pueden provocar eventos extremos como sequías e inundaciones. Por lo que, este factor pone en peligro la supervivencia de muchas especies y ecosistemas. Además, el cambio climático puede ser una gran amenaza para la identidad de las comunidades cuya forma de vida depende del medio ambiente. Por ello, esta revisión bibliográfica se centra en las consecuencias psicológicas que tiene el cambio climático en la salud mental. Los impactos directos de este fenómeno, como los incendios forestales o los impactos indirectos como la exposición repetida a información referente a las transformaciones que sufre el medio ambiente, pueden provocar alteraciones emocionales. Algunas de estas consecuencias pueden ser ansiedad, alteraciones del estado de ánimo o síndromes psicoterráticos. Un factor de riesgo podría ser un alto grado de neuroticismo, mientras que un factor protector sería un alto nivel de apertura. Por lo que, sería conveniente investigar intervenciones psicológicas que nos permitieran afrontarlo de una forma más adaptativa. Estas estrategias podrían estar enfocadas a promover la resiliencia y el compromiso conductual ante el desafío que plantea este fenómeno. Asimismo, sería recomendable desarrollar políticas que permitan alcanzar la meta número 13 de los Objetivos de Desarrollo Sostenible de la ONU, es decir, adoptar medidas urgentes para combatir el cambio climático y sus efectos

    Influence of organic matter and CO2 supply on bioremediation of heavy metals by Chlorella vulgaris and Scenedesmus almeriensis in a multimetallic matrix

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    Producción CientíficaThis research evaluated the influence of organic matter (OM) and CO2 addition on the bioremediation potential of two microalgae typically used for wastewater treatment: Chlorella vulgaris (CV) and Scenedesmus almeriensis (SA). The heavy metal (HM) removal efficiencies and biosorption capacities of both microalgae were determined in multimetallic solutions (As, B, Cu, Mn, and Zn) mimicking the highest pollutant conditions found in the Loa river (Northern Chile). The presence of OM decreased the total biosorption capacity, specially in As (from 2.2 to 0.0 mg/g for CV and from 2.3 to 1.7 mg/g for SA) and Cu (from 3.2 to 2.3 mg/g for CV and from 2.1 to 1.6 mg/g for SA), but its influence declined over time. CO2 addition decreased the total HM biosorption capacity for both microalgae species and inhibited CV growth. Finally, metal recovery using different eluents (HCl, NaOH, and CaCl2) was evaluated at two different concentrations. HCl 0.1 M provided the highest recovery efficiencies, which supported values over 85% of As, 92% of Cu, and ≈100% of Mn and Zn from SA. The presence of OM during the loaded stage resulted in a complete recovery of As, Cu, Mn, and Zn when using HCl 0.1 M as eluent.Gobierno regional de Castilla y León (UIC 071, CLU 2017-09 and VA080G18)Ministerio de Ciencia, Innovación y Universidades (project CTQ2017-84006-C3-1-R)Unión Europea - FEDER (CLU 2017-09 and CTQ2017-84006-C3-1-R

    Proliferative Diabetic Retinopathy and Hemovitreous: Red Flag for Blindness

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    The scars produced by the impact of laser photocoagulation appear as grey retinal round marks surrounding the temporal vascular arcades. Multiple dot and blot hemorrhages and microaneurysms can be seen in the posterior pole. There are two types of white abnormalities: multiple lipid exudate deposition near the macula and a couple of cotton-wool spots temporal to the optic disk. An abnormal tissue emerges from the optic nerve head as well as new vessels, which cannot be properly seen because of hemovitreou

    Continuous polyhydroxybutyrate production from biogas in an innovative two‐stage bioreactor configuration

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    Producción CientíficaBiogas biorefineries have opened up new horizons beyond heat and electricityproduction in the anaerobic digestion sector. Added‐value products such aspolyhydroxyalkanoates (PHAs), which are environmentally benign and potentialcandidates to replace conventional plastics, can be generated from biogas. Thiswork investigated the potential of an innovative two‐stage growth‐accumulationsystem for the continuous production of biogas‐based polyhydroxybutyrate (PHB)usingMethylocystis hirsutaCSC1 as cell factory. The system comprised twoturbulent bioreactors in series to enhance methane and oxygen mass transfer: acontinuous stirred tank reactor (CSTR) and a bubble column bioreactor (BCB) withinternal gas recirculation. The CSTR was devoted to methanotrophic growth undernitrogen balanced growth conditions and the BCB targeted PHB productionunder nitrogen limiting conditions. Two different operational approaches underdifferent nitrogen loading rates and dilution rates were investigated. A balancednitrogen loading rate along with a dilution rate (D) of 0.3 day−1resulted in the moststable operating conditions and a PHB productivity of ~53 g PHB m−3day−1.However, higher PHB productivities (~127 g PHB m−3day−1)wereachievedusingnitrogen excess at a D = 0.2 day−1. Overall, the high PHB contents (up to 48% w/w)obtained in the CSTR under theoretically nutrient balanced conditions and the poorprocess stability challenged the hypothetical advantages conferred by multistagevs single‐stage process configurations for long‐term PHB production.Ministerio de Ciencia e Innovación under (BES-2016-077160) contract and (project CTM2015-70442-R)Junta de Castilla y León and EU-FEDER program (UIC 315, CLU 2017-09
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