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Networks of social interactions are the substrate upon which civilizations are built. Often, we create new bonds with people that we like or feel that our relationships are damaged through the intervention of third parties. Despite their importance and the huge impact that these processes have in our lives, quantitative scientific understanding of them is still in its infancy, mainly due to the difficulty of collecting large datasets of social networks including individual attributes. In this work, we present a thorough study of real social networks of 13 schools, with more than 3,000 students and 60,000 declared positive and negative relationships, including tests for personal traits of all the students. We introduce a metric—the “triadic influence”—that measures the influence of nearest neighbors in the relationships of their contacts. We use neural networks to predict the sign of the relationships in these social networks, extracting the probability that two students are friends or enemies depending on their personal attributes or the triadic influence. We alternatively use a high-dimensional embedding of the network structure to also predict the relationships. Remarkably, using the triadic influence (a simple one-dimensional metric) achieves the best accuracy, and adding the personal traits of the students does not improve the results, suggesting that the triadic influence acts as a proxy for the social compatibility of students. We postulate that the probabilities extracted from the neural networks—functions of the triadic influence and the personalities of the students—control the evolution of real social networks, opening an avenue for the quantitative study of these systems. [ABSTRACT FROM AUTHOR]

Copyright of Eutopía: Revista de Desarrollo Económico Territorial is the property of Eutopia: Revista de Desarrollo Economico Territorial and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Neotropical Mammalogy / Mastozoologia Neotropical is the property of Sociedad Argentina para el Estudio de los Mamiferos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recent studies have shown that long non-coding RNAs (lncRNAs) have key functions during breast cancer development. Considering the complexity of IncRNAs regulatory network, the identification of novel and functional lncRNAs associated with breast cancer is thus very important. By using Agilent LncRNA Human Gene Expression Microarray, we identified a number of lncRNAs that were differentially expressed in breast cancer compared to their corresponding adjacent tissues. According to the microarray, the expression of p10247, henceforth named as lncRNA-BCHE (standing for lncRNA high expressed in breast cancer), was found to be uniformly higher in all the five breast cancer tissues tested, and this was further confirmed in 56 breast cancer tissues by real-time RT-PCR. The function of lncRNA-BCHE in breast cancer cells was tested by knockdown and over-expression experiments in vitro. We also analyzed the public cohorts of breast cancer patients on the Kaplan Meier plotter platform. Clinical analysis revealed that the expression of lncRNA-BCHE was significantly correlated with advanced clinical stage and lymph node metastasis. Our data indicate that lncRNA-BCHE regulates the growth, migration and invasion of breast cancer cells. In addition, we found that these functions are mediated, at least in part, by the regulation of integrin subunit beta 1 (ITGB1) levels. The expression of ITGB1 serves as a negative prognostic factor and metastasis risk predictor in breast cancer, irrespective of subtype and therapeutic regimen. In summary, our results suggest that lncRNA-BCHE is an oncogenic lncRNA enhancing the growth and metastatic potential of breast cancer cells, and a potential predictor of breast cancer metastatic progression. [ABSTRACT FROM AUTHOR]

In this paper, we study how the pro-social impact due to the vigilance by other individuals is conditioned by both environmental and evolutionary effects. To this aim, we consider a known model where agents play a Prisoner's Dilemma Game (PDG) among themselves and the pay-off matrix of an individual changes according to the number of neighbors that are "vigilant", i.e., how many neighbors watch out for her behavior. In particular, the temptation to defect decreases linearly with the number of vigilant neighbors. This model proved to support cooperation in specific conditions, and here we check its robustness with different topologies, microscopical update rules and initial conditions. By means of many numerical simulations and few theoretical considerations, we find in which situations the vigilance by the others is more effective in favoring cooperative behaviors and when its influence is weaker. [ABSTRACT FROM AUTHOR]

Copyright of MediSur is the property of Centro Provincial de Informacion de Ciencias Medicas de Cinfuegos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MediSur is the property of Centro Provincial de Informacion de Ciencias Medicas de Cinfuegos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents an agent-based model designed to explore the development of cooperation in hunter-fisher-gatherer societies that face a dilemma of sharing an unpredictable resource that is randomly distributed in space. The model is a stylised abstraction of the Yamana society, which inhabited the channels and islands of the southernmost part of Tierra del Fuego (Argentina-Chile). According to ethnographic sources, the Yamana developed cooperative behaviour supported by an indirect reciprocity mechanism: whenever someone found an extraordinary confluence of resources, such as a beached whale, they would use smoke signals to announce their find, bringing people together to share food and exchange different types of social capital. The model provides insight on how the spatial concentration of beachings and agents’ movements in the space can influence cooperation. We conclude that the emergence of informal and dynamic communities that operate as a vigilance network preserves cooperation and makes defection very costly. [ABSTRACT FROM AUTHOR]

Background It is estimated, there are around 370 million indigenous people in the world. For 2017, 5.4% of tuberculosis cases in Colombia occurred in the indigenous population (IP), while in the Cauca region, it was 32% and only 19.3% of new cases were detected. This is the second region with the highest proportion of IP in Colombia. This could affect the fulfillment of the aims of the Colombian Strategic Plan Towards the End of TB. Our aim was to evaluate the pulmonary tuberculosis (PTB) care cascade in IP of Cauca and identified gaps in the cascade. Methods Mixed methods (explanatory sequential desing). In the quantitative phase, the care cascade was evaluated. In the qualitative phase we sought to explain the gaps in the cascade. Tuberculosis program information and semi-structured interviews were used. Results In the care cascade in IP, 202 cases of presumptive PTB (New smear-positive expected) were estimated. A gap of undiagnosed cases of 47.5% was found (n = 96). This gap was explained by poor quality of the Acid-Fast Bacillus Smear, failures in the identification of presumptive tuberculosis, limited access to diagnostic methods, poor training and high turnover of healthcare workers were identified as possible explanations. Conclusions The efforts of the tuberculosis control program in the IP should focus on reducing the gap of undiagnosed cases. Key messages The PTB in IP could affect the fulfillment of the goals of the program. Approximately half of the expected cases were not detected during 2016-2017. [ABSTRACT FROM AUTHOR]

Congestible goods describe situations in which a group of people share or use a public good that becomes congested or overexploited when demand is low. We study experimentally a congestible goods problem of relevance for parking design, namely how people choose between a convenient parking lot with few spots and a less convenient one with unlimited space. We find that the Nash equilibrium predicts reasonably well the competition for the convenient parking when it has few spots, but not when it has more availability. We then show that the Rosenthal equilibrium, a bounded-rational approach, is a better description of the experimental results accounting for the randomness in the decision process. We introduce a dynamical model that shows how Rosenthal equilibria can be approached in a few rounds of the game. Our results give insights on how to deal with parking problems such as the design of parking lots in central locations in cities and open the way to better understand similar congestible goods problems in other contexts. [ABSTRACT FROM AUTHOR]

The problem of public good provision is central in economics and touches upon many challenging societal issues, ranging from climate change mitigation to vaccination schemes. However, results which are supposed to be applied to a societal scale have only been obtained with small groups of people, with a maximum group size of 100 being reported in the literature. This work takes this research to a new level by carrying out and analysing experiments on public good games with up to 1000 simultaneous players. The experiments are carried out via an online protocol involving daily decisions for extended periods. Our results show that within those limits, participants' behaviour and collective outcomes in very large groups are qualitatively like those in smaller ones. On the other hand, large groups imply the difficulty of conveying information on others' choices to the participants. We thus consider different information conditions and show that they have a drastic effect on subjects' contributions. We also classify the individual decisions and find that they can be described by a moderate number of types. Our findings allow to extend the conclusions of smaller experiments to larger settings and are therefore a relevant step forward towards the understanding of human behaviour and the organisation of our society. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Understanding whether the size of the interacting group has an effect on cooperative behavior has been a major topic of debate since the seminal works on cooperation in the 1960s. Half a century later, scholars have yet to reach a consensus, with some arguing that cooperation is harder in larger groups, while others that cooperation is easier in larger groups, and yet others that cooperation attains its maximum in intermediate size groups. Here we add to this field of work by reporting a two-treatment empirical study where subjects play a Public Goods Game with a Critical Mass, such that the return for full cooperation increases linearly for early contributions and then stabilizes after a critical mass is reached (the two treatments differ only on the critical mass). We choose this game for two reasons: it has been argued that it approximates real-life social dilemmas; previous work suggests that, in this case, group size might have an inverted-U effect on cooperation, where the pick of cooperation is reached around the critical mass. Our main innovation with respect to previous experiments is that we implement a within-subject design, such that the same subject plays in groups of different size (from 5 to 40 subjects). Groups are formed at random at every round and there is no feedback. This allows us to explore if and how subjects change their choice as a function of the size of the group. We report three main results, which partially contrast what has been suggested by previous work: in our setting (i) the critical mass has no effect on cooperation; (ii) group size has a positive effect on cooperation; (iii) the most chosen option (played by about 50% of the subjects) is All Defection, followed by All Cooperation (about 10% of the subjects), whereas the rest have a slight trend to switch preferentially from defection to cooperation as the group size increases. [ABSTRACT FROM AUTHOR]

We study the influence that resource availability has on cooperation in the context of hunter-gatherer societies. This paper proposes a model based on archaeological and ethnographic research on resource stress episodes, which exposes three different cooperative regimes according to the relationship between resource availability in the environment and population size. The most interesting regime represents moderate survival stress in which individuals coordinate in an evolutionary way to increase the probabilities of survival and reduce the risk of failing to meet the minimum needs for survival. Populations self-organise in an indirect reciprocity system in which the norm that emerges is to share the part of the resource that is not strictly necessary for survival, thereby collectively lowering the chances of starving. Our findings shed further light on the emergence and evolution of cooperation in hunter-gatherer societies. [ABSTRACT FROM AUTHOR]