Detection of Trending Topic Communities: Bridging Content Creators and Distributors

The rise of a trending topic on Twitter or Facebook leads to the temporal emergence of a set of users currently interested in that topic. Given the temporary nature of the links between these users, being able to dynamically identify communities of users related to this trending topic would allow for a rapid spread of information. Indeed, individual users inside a community might receive recommendations of content generated by the other users, or the community as a whole could receive group recommendations, with new content related to that trending topic. In this paper, we tackle this challenge, by identifying coherent topic-dependent user groups, linking those who generate the content (creators) and those who spread this content, e.g., by retweeting/reposting it (distributors). This is a novel problem on group-to-group interactions in the context of recommender systems. Analysis on real-world Twitter data compare our proposal with a baseline approach that considers the retweeting activity, and validate it with standard metrics. Results show the effectiveness of our approach to identify communities interested in a topic where each includes content creators and content distributors, facilitating users' interactions and the spread of new information.Comment: 9 pages, 4 figures, 2 tables, Hypertext 2017 conferenc

Predicting workout quality to help coaches support sportspeople

The support of a qualified coach is crucial to keep the motivation of sportspeople high and help them pursuing an active lifestyle. In this paper,we discuss the scenario in which a coach follows sportspeople remotely by means of an eHealth platform, named u4fit. Having to deal with several users at the same time, with no direct human contact, means that it is hard for coaches to quickly spot who, among the people she follows, needs a more timely support. To this end, in this paper we present an automated approach that analyzes the adherence of sportspeople to their planned workout routines. The approach is able to suggest to the coach the sportspeople who need earlier support due to a poor performance. Experiments on real data, evaluated through classic accuracy metrics, show the effectiveness of our approach

Régénération tissulaire guidée: observation ultrastructurale au microscope électronique à transmission et au microscope électronique à balayage

PTFE membranes are used for guided tissue regeneration in oder to treat angular bone defects or forcation involvements in surgical treatment.Ultrastructural investigations have been performed by means of electron transmission and scanning microscopy. In agreement with previous reports, fibroblast cells adhering to the reticular structure of PTFE membrane were observed; these were interposed among coagulated clusters of fibrinous material and blood cells round shaped. Elongated bacterial cells were always present in the microscope fields analysed.These observations were confirmed by means of transmission microscopy; moreover specific techniques enabled us to demonstrate that fibroblast cells were synthetizing collagene, which was present in the form of extracellular fibers mixed to fibrine clusters. Roundish and elongate bacterial cells were always observed both in the extracellular matrix and into macrophages.Les Auteurs ont effectué des recherches ultrastructurales au M.E.T. et au M.E.B. sur quelques membranes de PTFE employées pour guider la régénération tissulaire dans la correction de défauts osseux angulaires ou de la zone de la bifurcation radiculaire après traitement chirurgical.Les observations au M.E.B. ont confirmé celles que d’autres auteurs ont effectuées en mettant en évidence, à la surface des membranes des corps cellulaires de fibroblastes adhérents aux structures réticulaires du PTFE, mélangés à des amas coagulés de matériel fibrineux et à des éléments figurés du sang.En outre, la présence, dans les champs examinés, de corps bactériens à forme ronde et allongée, est constante, signe de contamination bactérienne.Au M.E.T., ces observations ont trouvé une correspondance exacte et les techniques spécifiques ont permis de démontrer que les cellules fibroblastes présentes sont en phase active de synthèse de collagène. Ce dernier apparaît amassé en position extracellulaire, mélangé aux amas de fibrine.De la même façon on a démontré la présence, aussi bien en position extra-cellulaire qu’à l’intérieur desmacrophages, des corps bactériens ronds et allongés

Preface to the special issue on harnessing personal tracking data for personalization and sense-making

Increasingly, people are making use of diverse digital services that create many types of personal data. The most recent addition to such services are self-tracking devices that are capable of creating very detailed personal activity records. The focus of this special issue is to explore how such activity records can be exploited to provide user-centric personalization services

Using Case-Based Reasoning to Predict Marathon Performance and Recommend Tailored Training Plans

The 28th International Conference on Case-Based Reasoning (ICCP 2020), Salamanca, Spain (held online due to coronavirus outbreak), 8-12 June 2020Training for the marathon, especially a first marathon, is always a challenge. Many runners struggle to find the right balance between their workouts and their recovery, often leading to sub-optimal performance on race-day or even injury during training. We describe and evaluate a novel case-based reasoning system to help marathon runners as they train in two ways. First, it uses a case-base of training/workouts and race histories to predict future marathon times for a target runner, throughout their training program, helping runners to calibrate their progress and, ultimately, plan their race-day pacing. Second, the system recommends tailored training plans to runners, adapted for their current goal-time target, and based on the training plans of similar runners who have achieved this time. We evaluate the system using a dataset of more than 21,000 unique runners and 1.5 million training/workout sessions.Science Foundation IrelandInsight Research Centre2020-10-06 JG: PDF replaced with correct versio

Modeling a mobile group recommender system for tourism with intelligent agents and gamification

To provide recommendations to groups of people is a complex task, especially due to the group’s heterogeneity and conflicting preferences and personalities. This heterogeneity is even deeper in occasional groups formed for predefined tour packages in tourism. Group Recommender Systems (GRS) are being designed for helping in situations like those. However, many limitations can still be found, either on their time-consuming configurations and excessive intrusiveness to build the tourists’ profile, or in their lack of concern for the tourists’ interests during the planning and tours, like feeling a greater liberty, diminish the sense of fear/being lost, increase their sense of companionship, and promote the social interaction among them without losing a personalized experience. In this paper, we propose a conceptual model that intends to enhance GRS for tourism by using gamification techniques, intelligent agents modeled with the tourists’ context and profile, such as psychological and socio-cultural aspects, and dialogue games between the agents for the post-recommendation process. Some important aspects of a GRS for tourism are also discussed, opening the way for the proposed conceptual model, which we believe will help to solve the identified limitations.This work was supported by the GrouPlanner Project (POCI-01-0145-FEDER-29178) and by National Funds through the FCT –Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within the Projects UID/CEC/00319/2019 and UID/EEA/00760/2019

NightSplitter: a scheduling tool to optimize (sub)group activities

International audienceHumans are social animals and usually organize activities in groups. However, they are often willing to split temporarily a bigger group in subgroups to enhance their preferences. In this work we present NightSplitter, an on-line tool that is able to plan movie and dinner activities for a group of users, possibly splitting them in subgroups to optimally satisfy their preferences. We first model and prove that this problem is NP-complete. We then use Constraint Programming (CP) or alternatively Simulated Annealing (SA) to solve it. Empirical results show the feasibility of the approach even for big cities where hundreds of users can select among hundreds of movies and thousand of restaurants

Magic-factor 1, a partial agonist of Met, induces muscle hypertrophy by protecting myogenic progenitors from apoptosis.

Hepatocyte Growth Factor (HGF) is a pleiotropic cytokine of mesenchymal origin that mediates a characteristic array of biological activities including cell proliferation, survival, motility and morphogenesis. Its high affinity receptor, the tyrosine kinase Met, is expressed by a wide range of tissues and can be activated by either paracrine or autocrine stimulation. Adult myogenic precursor cells, the so called satellite cells, express both HGF and Met. Following muscle injury, autocrine HGF-Met stimulation plays a key role in promoting activation and early division of satellite cells, but is shut off in a second phase to allow myogenic differentiation. In culture, HGF stimulation promotes proliferation of muscle precursors thereby inhibiting their differentiation