Evolution Reinforces Cooperation with the Emergence of Self-Recognition Mechanisms: an empirical study of the Moran process for the iterated Prisoner's dilemma

We present insights and empirical results from an extensive numerical study of the evolutionary dynamics of the iterated prisoner's dilemma. Fixation probabilities for Moran processes are obtained for all pairs of 164 different strategies including classics such as TitForTat, zero determinant strategies, and many more sophisticated strategies. Players with long memories and sophisticated behaviours outperform many strategies that perform well in a two player setting. Moreover we introduce several strategies trained with evolutionary algorithms to excel at the Moran process. These strategies are excellent invaders and resistors of invasion and in some cases naturally evolve handshaking mechanisms to resist invasion. The best invaders were those trained to maximize total payoff while the best resistors invoke handshake mechanisms. This suggests that while maximizing individual payoff can lead to the evolution of cooperation through invasion, the relatively weak invasion resistance of payoff maximizing strategies are not as evolutionarily stable as strategies employing handshake mechanisms

Reinforcement Learning Produces Dominant Strategies for the Iterated Prisoner's Dilemma

We present tournament results and several powerful strategies for the Iterated Prisoner's Dilemma created using reinforcement learning techniques (evolutionary and particle swarm algorithms). These strategies are trained to perform well against a corpus of over 170 distinct opponents, including many well-known and classic strategies. All the trained strategies win standard tournaments against the total collection of other opponents. The trained strategies and one particular human made designed strategy are the top performers in noisy tournaments also

A realist evaluation of a multi-component program with disengaged students

Periods spent in the absence of education, employment, or training (NEET) are associated with adverse psychological wellbeing, social marginalisation, and premature mortality. Implementing effective programs to re-engage young people who are classified, or are at risk of becoming NEET, is of importance to these individuals, family, and society. We conducted a realist evaluation to understand how, and under which circumstances a multi-component program may impact the engagement, behavioural, and psychosocial outcomes of disengaged students at risk of becoming NEET. During the early project phase, a narrative review of the literature and key stakeholder discussions were conducted to develop our initial program theories regarding how the program was expected to achieve its outcomes. Participant observations, video footage, and forty-two interviews were then conducted with teachers and students to form context-mechanism-outcome configurations and to refine these theories. Overall, refined program theories relating to positions of authority, the power of collective experience, exploration of possible life directions, constructivist pedagogies and active learning, and the endorsement of an ethic of caring and strengths-based orientation were developed. Collectively, our findings provide a detailed understanding of the architecture of programs that may benefit disengaged students and help inform the design of future programs aimed at reducing disaffection

The role of micrornas in the development of hospital acquired infection in polytrauma patients

Introduction Traumatic injury is associated with immunosuppression and an increased risk of developing nosocomial infections. However, the immune regulatory mechanisms involved remain unclear. Objectives 1) To describe genome-wide alterations in micro RNA (miRNA) expression following severe trauma. 2) To explore the potential role of miRNAs in mediating the post-traumatic immunosuppressive phenotype and their potential role in enhancing the risk of nosocomial infections. Methods Patients requiring ICU care following traumatic injury were recruited. Whole blood was collected within 2 hours of injury and 24 hours later. Total RNA (containing miRNAs) was isolated utilising PAX Gene and RNA extraction kits (Qiagen). miRNA-sequencing was performed with the Illumina HiSeq2500, and sequences were aligned to the human GRCh37 reference genome. Data analysis was carried out using the DESEQ2 package in R, and miRNAs were considered significantly altered with an adjusted p value of < 0.05. Functional enrichment analysis was performed using Ingenuity Pathway Analysis (IPA) on all miRNAs reaching an adjusted p value of < 0.1. mRNA targets of interest were identified using miRBase and TargetScan (http://www.mirbase.org, http://www.targetscan.org). Results 49 patients were recruited and 25 patients developed nosocomial infections. Expression of 139 miRNAs was significantly altered between 2 hours and 24 hours following injury, with miR-146b, a key inhibitor of pro-inflammatory pathways[1], upregulated to the greatest degree. Figure 1 presents miRNAs that differ between those patients who developed nosocomial infections and those who did not. miR-144-5p was significantly different between the two groups at both time points. a large percentage of mRNA targets for miR-144 are involved the Cell-mediated Immune Response (Figure 2), including the B-cell receptor complex, p38MAPK, GATA3, IgG, BCL6 and the T-cell receptor. in addition, we have previously shown that the miR-374 family of miRNAs is linked to increased IL-10 expression in trauma patients[2]. IPA highlights Cancer, Haematological Disease, Immunological and Inflammatory Disease and Organismal Injury and Abnormalities as important pathways altered between infected and non-infected patients. Conclusions These data provide a miRNA signature of severely injured trauma patients who develop hospital acquired infection compared to those who do not, and identify the miR-144 and miR-374b families as being of particular interest for future studies of trauma-induced immune dysfunction

Keeping Girls in Sport: A Two-Part Evaluation of an E-Learning Program for Coaches and Activity Leaders

The purpose of this study was twofold: first, to identify who engaged with the Keeping Girls in Sport e-learning program and, second, to evaluate coach and activity leaders’ perceptions of the program and their perceived learnings gained from completing the program. An explanatory sequential mixed-method design was adopted. First, an online survey was distributed to all individuals who had participated in the program. In total, 511 (33% response rate) completed the survey. Quantitative survey data were analysed using descriptive statistics. Subsequently, interviews were conducted with 20 survey respondents. A realist logic of analysis was applied to the qualitative data, and context–mechanism–outcome configurations were formed. Overall, survey findings indicated that most participants identified as women (56%), coaches (69%), and were between 40 and 49 years of age (37%). In general, participants had positive perceptions of the program. Participants perceived that the accessibility and flexibility of the program increased opportunities to engage with content and, thus, their learning. They described improvements in knowledge and perspective regarding working with female athletes. This increase in knowledge provided participants with confidence to establish trusting and positive relationships with others, specifically parents. Nevertheless, participants highlighted a need for more tailored but also more expansive programs

Giant Strengthening of Superconducting Pairing in Metallic Nanoclusters

The presence of shell structure and the accompanying high level degeneracy leads to a strengthening of the pairing interaction in some metallic nanoclusters and ions. It is predicted that for some specific systems one can expect a large increase in the values of the critical temperature and other parameters

Unsupervised multi-word term recognition in Welsh

This paper investigates an adaptation of an existing system for multi-word term recognition, originally developed for English, for Welsh. We overview the modifications required with a special focus on an important difference between the two representatives of two language families, Germanic and Celtic, which is concerned with the directionality of noun phrases. We successfully modelled these differences by means of lexico–syntactic patterns, which represent parameters of the system and, therefore, required no re–implementation of the core algorithm. The performance of the Welsh version was compared against that of the English version. For this purpose, we assembled three parallel domain–specific corpora. The results were compared in terms of precision and recall. Comparable performance was achieved across the three domains in terms of the two measures (P = 68.9%, R = 55.7%), but also in the ranking of automatically extracted terms measured by weighted kappa coefficient (k = 0.7758). These early results indicate that our approach to term recognition can provide a basis for machine translation of multi-word terms