1,041 research outputs found

    The Multidimensional Study of Viral Campaigns as Branching Processes

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    Viral campaigns on the Internet may follow variety of models, depending on the content, incentives, personal attitudes of sender and recipient to the content and other factors. Due to the fact that the knowledge of the campaign specifics is essential for the campaign managers, researchers are constantly evaluating models and real-world data. The goal of this article is to present the new knowledge obtained from studying two viral campaigns that took place in a virtual world which followed the branching process. The results show that it is possible to reduce the time needed to estimate the model parameters of the campaign and, moreover, some important aspects of time-generations relationship are presented.Comment: In proceedings of the 4th International Conference on Social Informatics, SocInfo 201

    Sobre la biología del águila calzada Hieraëtus pennatus (Gmelin, 1788) en Navarra

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    Trata el presente trabajo de aspectos de la Biología del Águila calzada (Hieraétus pennatus) durante el período reproductor según observaciones realizadas en unos parajes de la zona media de Navarra. Comienza con la descripción del sistema de trabajo y posteriormente, se describe la especie, su habitat, distribución geográfica y estatus en Navarra. Según fechas de observación de los autores se trata de la fenología de migración. Un capítulo más extenso describe el comportamiento territorial y nupcial de la especie y se dan todos los datos básicos relativos a fechas de puesta de huevos, nacimiento de los pollos, período de dependencia con sus padres etc. Se citan observaciones originales relativas a la agresividad entre los pollos en varias especies de rapaces. Se dan datos sobre alimentación de las especies y el trabajo acaba describiendo los cambios de los individuos que compusieron una pareja de águilas calzadas que nidificó en el mismo bosque durante 17 años, pudiéndose estudiar, por ello, la productividad de tal pareja en dicho período de tiempo

    Effects of mindfulness-based cognitive therapy on mental disorders: a systematic review and meta-analysis of randomised controlled trials.

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    OBJECTIVE: Mindfulness-based cognitive therapy (MBCT) is a programme developed to prevent depression relapse, but has been applied for other disorders. Our objective was to systematically review and meta-analyse the evidence on the effectiveness and safety of MBCT for the treatment of mental disorders. METHODS: Searches were completed in CENTRAL, MEDLINE, EMBASE, LILACS, PsychINFO, and PsycEXTRA in March 2011 using a search strategy with the terms 'mindfulness-based cognitive therapy', 'mindfulness', and 'randomised controlled trials' without time restrictions. Selection criteria of having a randomised controlled trial design, including patients diagnosed with mental disorders, using MBCT according to the authors who developed MBCT and providing outcomes that included changes in mental health were used to assess 608 reports. Two reviewers applied the pre-determined selection criteria and extracted the data into structured tables. Meta-analyses and sensitivity analyses were completed. RESULTS: Eleven studies were included. Most of them evaluated depression and compared additive MBCT against usual treatment. After 1 year of follow-up MBCT reduced the rate of relapse in patients with three or more previous episodes of depression by 40% (5 studies, relative risk [95% confidence interval]: 0.61 [0.48, 0.79]). Other meta-analysed outcomes were depression and anxiety, both with significant results but unstable in sensitivity analyses. Methodological quality of the reports was moderate. CONCLUSION: Based on this review and meta-analyses, MBCT is an effective intervention for patients with three or more previous episodes of major depression

    Smartphone Applications to Support Tuberculosis Prevention and Treatment: Review and Evaluation

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    Background: Tuberculosis (TB) remains a major global health problem and is the leading killer due to a single infectious disease. Mobile health (mHealth)–based tools such as smartphone apps have been suggested as tools to support TB control efforts (eg, identification, contact tracing, case management including patient support). Objective: The purpose of this review was to identify and assess the functionalities of mobile apps focused on prevention and treatment of TB. Methods: We searched 3 online mobile app stores. Apps were included if they were focused on TB and were in English, Spanish, or Portuguese. For each included app, 11 functionalities were assessed (eg, inform, instruct, record), and searches were conducted to identify peer-review publications of rigorous testing of the available apps. Results: A total of 1332 potentially relevant apps were identified, with 24 meeting our inclusion criteria. All of the apps were free to download, but 7 required login and password and were developed for specific clinics, regional sites, or research studies. Targeted users were mainly clinicians (n=17); few (n=4) apps were patient focused. Most apps (n=17) had 4 or fewer functions out of 11 (range 1-6). The most common functionalities were inform and record (n=15). Although a number of apps were identified with various functionalities to support TB efforts, some had issues such as incorrect spelling and grammar, inconsistent responses to data entry, problems with crashing, or links to features that had no data. Of more concern, some apps provided potentially harmful information to patients, such as links to natural remedies for TB and natural healers. One-third of the apps (8/24) had not been updated for more than a year and may no longer be supported. Peer-reviewed publications were identified for only two of the included apps. In the gray literature (not found in the app stores), three TB-related apps were identified as in progress, being launched, or tested. Conclusions: Apps identified for TB prevention and treatment had minimal functionality, primarily targeted frontline health care workers, and focused on TB information (eg, general information, guidelines, and news) or data collection (eg, replace paper-based notification or tracking). Few apps were developed for use by patients and none were developed to support TB patient involvement and management in their care (eg, follow-up alerts/reminders, side effects monitoring) or improve interaction with their health care providers, limiting the potential of these apps to facilitate patient-centered care. Our evaluation shows that more refined work is needed to be done in the area of apps to support patients with active TB. Involving TB patients in treatment in the design of these apps is recommended

    The evolution of Balmer jump selected galaxies in the ALHAMBRA survey

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    We present a new color-selection technique, based on the Bruzual & Charlot models convolved with the bands of the ALHAMBRA survey, and the redshifted position of the Balmer jump to select star-forming galaxies in the redshift range 0.5 < z < 1.5. These galaxies are dubbed Balmer jump Galaxies BJGs. We apply the iSEDfit Bayesian approach to fit each detailed SED and determine star-formation rate (SFR), stellar mass, age and absolute magnitudes. The mass of the haloes where these samples reside are found via a clustering analysis. Five volume-limited BJG sub-samples with different mean redshifts are found to reside in haloes of median masses 1012.5±0.2M\sim 10^{12.5 \pm 0.2} M_\odot slightly increasing toward z=0.5. This increment is similar to numerical simulations results which suggests that we are tracing the evolution of an evolving population of haloes as they grow to reach a mass of 1012.7±0.1M\sim 10^{12.7 \pm 0.1} M_\odot at z=0.5. The likely progenitors of our samples at z\sim3 are Lyman Break Galaxies, which at z\sim2 would evolve into star-forming BzK galaxies, and their descendants in the local Universe are elliptical galaxies.Hence, this allows us to follow the putative evolution of the SFR, stellar mass and age of these galaxies. From z\sim1.0 to z\sim0.5, the stellar mass of the volume limited BJG samples nearly does not change with redshift, suggesting that major mergers play a minor role on the evolution of these galaxies. The SFR evolution accounts for the small variations of stellar mass, suggesting that star formation and possible minor mergers are the main channels of mass assembly.Comment: 14 pages, 10 figures. Submitted to A&A. It includes first referee's comments. Abstract abridged due to arXiv requirement

    Random Walks on Stochastic Temporal Networks

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    In the study of dynamical processes on networks, there has been intense focus on network structure -- i.e., the arrangement of edges and their associated weights -- but the effects of the temporal patterns of edges remains poorly understood. In this chapter, we develop a mathematical framework for random walks on temporal networks using an approach that provides a compromise between abstract but unrealistic models and data-driven but non-mathematical approaches. To do this, we introduce a stochastic model for temporal networks in which we summarize the temporal and structural organization of a system using a matrix of waiting-time distributions. We show that random walks on stochastic temporal networks can be described exactly by an integro-differential master equation and derive an analytical expression for its asymptotic steady state. We also discuss how our work might be useful to help build centrality measures for temporal networks.Comment: Chapter in Temporal Networks (Petter Holme and Jari Saramaki editors). Springer. Berlin, Heidelberg 2013. The book chapter contains minor corrections and modifications. This chapter is based on arXiv:1112.3324, which contains additional calculations and numerical simulation
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