Identifying meaningful facial configurations during iterative prisoner’s dilemma games

The contraction and relaxation of facial muscles in humans is widely assumed to fulfil communicative and adaptive functions. However, to date most work has focussed either on individual muscle movements (action units) in isolation or on a small set of configurations commonly assumed to express “basic emotions”. As such, it is as yet unclear what information is communicated between individuals during naturalistic social interactions and how contextual cues influence facial activity occurring in these exchanges. The present study investigated whether consistent patterns of facial action units occur during dyadic iterative prisoners’ dilemma games, and what these patterns of facial activity might mean. Using exploratory and confirmatory factor analyses, we identified three distinct and consistent configurations of facial musculature change across three different datasets. These configurations were associated with specific gameplay outcomes, suggesting that they perform psychologically meaningful context-related functions. The first configuration communicated enjoyment and the second communicated affiliation and appeasement, both indicating cooperative intentions after cooperation or defection respectively. The third configuration communicated disapproval and encouraged social partners not to defect again. Future work should validate the occurrence and functionality of these facial configurations across other kinds of social interaction

World History: Cultures, States, and Societies to 1500

Editor\u27s Description: World History: Cultures, States, and Societies to 1500 offers a comprehensive introduction to the history of humankind from prehistory to 1500. Authored by six USG faculty members with advance degrees in History, this textbook offers up-to-date original scholarship. It covers such cultures, states, and societies as Ancient Mesopotamia, Ancient Israel, Dynastic Egypt, India’s Classical Age, the Dynasties of China, Archaic Greece, the Roman Empire, Islam, Medieval Africa, the Americas, and the Khanates of Central Asia. It includes 350 high-quality images and maps, chronologies, and learning questions to help guide student learning. Its digital nature allows students to follow links to applicable sources and videos, expanding their educational experience beyond the textbook. It provides a new and free alternative to traditional textbooks, making World History an invaluable resource in our modern age of technology and advancement. Ancillary resources for this textbook were created under a Round 18 Continuous Improvement Grant.https://oer.galileo.usg.edu/history-textbooks/1001/thumbnail.jp

Environmental Perturbations that Cause Structural Changes in the SNARE Protein SNAP-25

Digitalitzat per Artypla

Identification of a triplet pair intermediate in singlet exciton fission in solution.

Singlet exciton fission is the spin-conserving transformation of one spin-singlet exciton into two spin-triplet excitons. This exciton multiplication mechanism offers an attractive route to solar cells that circumvent the single-junction Shockley-Queisser limit. Most theoretical descriptions of singlet fission invoke an intermediate state of a pair of spin-triplet excitons coupled into an overall spin-singlet configuration, but such a state has never been optically observed. In solution, we show that the dynamics of fission are diffusion limited and enable the isolation of an intermediate species. In concentrated solutions of bis(triisopropylsilylethynyl)[TIPS]--tetracene we find rapid (<100 ps) formation of excimers and a slower (∼ 10 ns) break up of the excimer to two triplet exciton-bearing free molecules. These excimers are spectroscopically distinct from singlet and triplet excitons, yet possess both singlet and triplet characteristics, enabling identification as a triplet pair state. We find that this triplet pair state is significantly stabilized relative to free triplet excitons, and that it plays a critical role in the efficient endothermic singlet fission process.H.L.S was supported by the Winton Programme for the Physics of Sustainability and A.J.M received funding from the Engineering and Physical Sciences Research Council.This is the accepted manuscript. The final version is available at http://www.pnas.org/content/112/25/7656.abstract

IL-17A both initiates, via IFNγ suppression, and limits the pulmonary type-2 immune response to nematode infection

Nippostrongylus brasiliensis is a well-defined model of type-2 immunity but the early lung-migrating phase is dominated by innate IL-17A production. In this study, we confirm previous observations that Il17a-KO mice infected with N. brasiliensis exhibit an impaired type-2 immune response. Transcriptional profiling of the lung on day 2 of N. brasiliensis infection revealed an increased Ifng signature in Il17a-KO mice confirmed by enhanced IFNγ protein production in lung lymphocyte populations. Depletion of early IFNγ rescued type-2 immune responses in the Il17a-KO mice demonstrating that IL-17A-mediated suppression of IFNγ promotes type-2 immunity. Notably, later in infection, once the type-2 response was established, IL-17A limited the magnitude of the type-2 response. IL-17A regulation of type-2 immunity was lung-specific and infection with Trichuris muris revealed that IL-17A promotes a type-2 immune response in the lung even when infection is restricted to the intestine. Together our data reveal IL-17A as a major regulator of pulmonary type-2 immunity such that IL-17A supports early development of a protective type-2 response by suppression of IFNγ but subsequently limits excessive type-2 responses. A failure of this feedback loop may contribute to conditions such as severe asthma, characterised by combined elevation of IL-17 and type-2 cytokines

Intergroup emotional exchange: Ingroup guilt and outgroup anger increase resource allocation in trust games

Intergroup exchanges are an integral part of social life but are compromised when one group pursues its interests at another group’s expense. The present research investigates whether expressing emotion can mitigate the negative consequences of such actions. We examine how emotions communicated by either an ingroup or outgroup member following an ingroup member’s breach of trust affect other ingroup members’ feelings of guilt and pride, and subsequent allocation of resources. In both studies, groups of participants played a two-round trust game with another group. In round one, they observed a member of their own group failing to reciprocate a trusting move by the outgroup. In Study 1 (N = 85), an outgroup member then communicated anger or disappointment, whereas in Study 2 (N = 164), an ingroup member then communicated happiness or guilt. Comparisons with no-emotion control conditions revealed that expressions of outgroup anger and ingroup guilt increased participants’ allocations to an outgroup member in round two. The effect of an outgroup member’s anger expression was mediated by participants’ diminished feelings of pride about the ingroup action, whereas the effect of an ingroup member’s guilt expression was mediated by participants’ own feelings of guilt. Taken together, these findings support a social appraisal approach and highlight the roles that pride and guilt can play in shaping intergroup resource allocations