Replication strategies and the evolution of cooperation by exploitation

Introducing the concept of replication strategies this paper studies the evolution of cooperation in populations of agents whose offspring follow a social strategy that is determined by a parent's replication strategy. Importantly, social and replication strategies may differ, thus allowing parents to construct their own social niche, defined by the behaviour of their offspring. We analyse the co-evolution of social and replication strategies in well-mixed and spatial populations. In well-mixed populations, cooperation-supporting equilibria can only exist if the transmission processes of social strategies and replication strategies are completely separate. In space, cooperation can evolve without complete separation of the timescales at which both strategy traits are propagated. Cooperation then evolves through the presence of offspring exploiting defectors whose presence and spatial arrangement can shield clusters of pure cooperators

Resting-state functional connectivity following a single dose treatment with CB1 neutral antagonist tetrahydrocannabivarin (THCv) in healthy volunteers

BACKGROUND: The cannabinoid cannabinoid type 1 (CB1) neutral antagonist tetrahydrocannabivarin (THCv) has been suggested as a possible treatment for obesity, but without the depressogenic side-effects of inverse antagonists such as Rimonabant. However, how THCv might affect the resting state functional connectivity of the human brain is as yet unknown. METHOD: We examined the effects of a single 10mg oral dose of THCv and placebo in 20 healthy volunteers in a randomized, within-subject, double-blind design. Using resting state functional magnetic resonance imaging and seed-based connectivity analyses, we selected the amygdala, insula, orbitofrontal cortex, and dorsal medial prefrontal cortex (dmPFC) as regions of interest. Mood and subjective experience were also measured before and after drug administration using self-report scales. RESULTS: Our results revealed, as expected, no significant differences in the subjective experience with a single dose of THCv. However, we found reduced resting state functional connectivity between the amygdala seed region and the default mode network and increased resting state functional connectivity between the amygdala seed region and the dorsal anterior cingulate cortex and between the dmPFC seed region and the inferior frontal gyrus/medial frontal gyrus. We also found a positive correlation under placebo for the amygdala-precuneus connectivity with the body mass index, although this correlation was not apparent under THCv. CONCLUSION: Our findings are the first to show that treatment with the CB1 neutral antagonist THCv decreases resting state functional connectivity in the default mode network and increases connectivity in the cognitive control network and dorsal visual stream network. This effect profile suggests possible therapeutic activity of THCv for obesity, where functional connectivity has been found to be altered in these regions

Neural signals of “intensity” but not “wanting” or “liking” of rewards may be trait markers for depression

We have shown previously that particpants “at risk” of depression have decreased neural processing of reward suggesting this might be a neural biomarker for depression. However, how the neural signal related to subjective experiences of reward (wanting, liking, intensity) might differ as trait markers for depression, is as yet unknown. Using SPM8 parametric modulation analysis the neural signal related to the subjective report of wanting, liking and intensity was compared between 25 young people with a biological parent with depression (FH) and 25 age/gender matched controls. In a second study the neural signal related to the subjective report of wanting, liking and intensity was compared between 13 unmedicated recovered depressed (RD) patients and 14 healthy age/gender matched controls. The analysis revealed differences in the neural signal for wanting, liking and intensity ratings in the ventral striatum, dmPFC and caudate respectively in the RD group compared to controls . Despite no differences in the FH groups neural signal for wanting and liking there was a difference in the neural signal for intensity ratings in the dACC and anterior insula compared to controls. These results suggest that the neural substrates tracking the intensity but not the wanting or liking for rewards and punishers might be a trait marker for depression

Observe, Coach, Assist, and Report: An Emerging Framework for Integrating Unregulated Healthcare Providers into Interdisciplinary Healthcare Teams

Background: Unregulated healthcare providers known as personal support workers (PSWs) provide the majority of home care services in Ontario, Canada. However, there is little direction to guide their activities as members of interdisciplinary healthcare teams. The purpose of this study was to explore and describe the role of PSWs in interdisciplinary evidence-based stroke care.Methods and Findings: A concurrent triangulation mixed-methods design was used. Data sources included surveys (N = 270), chart audits (N = 234), interviews (N = 28), focus groups (N = 7), textbook review, an advisory committee (N = 14), and knowledge fairs (N = 112). PSWs can participate in team-based stroke care by observing vital information about clients in their homes, coaching clients to follow care plans, assisting to implement recommendations made by other healthcare providers, and reporting client progress, challenges, needs, and preferences to the healthcare team.Conclusions: The Observe, Coach, Assist, and Report (OCAR) themes have the potential to be used as a framework to guide improvements in intra-team communication, information sharing, and awareness of the PSW role, in order to support a more integrated home care experience for clients and families. Next steps include pilot testing the OCAR framework at the point of care in various settings to enhance interdisciplinary collaboration that is inclusive of PSWs

The impacts of human activity on mammals in a community forest near the Dja Biosphere Reserve in Cameroon

Human activity in African tropical rainforests continues to threaten wild mammals. Many rural communities are dependent on hunting, yet there is a widespread lack of baseline data on ecology and the sustainability of hunting. We investigated the impacts of human activity on mammal species composition and distributions within a community forest surrounding a village in the buffer zone of the Dja Biosphere Reserve in south-east Cameroon. We conducted a camera-trap survey in August–November 2017 and detected 24 mammal species, including Critically Endangered western lowland gorilla Gorilla gorilla gorilla, Endangered central African chimpanzee Pan troglodytes troglodytes and Endangered tree pangolin Phataginus tricuspis. We used occupancy analysis to explore relationships between indicators of human activity (distance to a road and the Reserve), habitat quality (distance to the river and tree cover) and the distributions of species. We found that the local distribution of threatened mammals was not apparently limited by human activity, and proximity to the road did not negatively influence occupancy for any species. However, most of the Reserve's large species were not detected, including the African forest elephant Loxodonta cyclotis and the largest ungulates, and the occupancy of two species commonly hunted for wild meat was positively correlated with distance from the village, indicating hunting may be unsustainable. Our results show that the community forest provides habitat for threatened species outside the Reserve and in close proximity to people. However, effective conservation management will require continued monitoring and research to determine whether current rates of hunting are sustainable

Observe, Coach, Assist, and Report: An Emerging Framework for Integrating Unregulated Healthcare Providers into Interdisciplinary Healthcare Teams

Background: Unregulated healthcare providers known as personal support workers (PSWs) provide the majority of home care services in Ontario, Canada. However, there is little direction to guide their activities as members of interdisciplinary healthcare teams. The purpose of this study was to explore and describe the role of PSWs in interdisciplinary evidence-based stroke care.Methods and Findings: A concurrent triangulation mixed-methods design was used. Data sources included surveys (N = 270), chart audits (N = 234), interviews (N = 28), focus groups (N = 7), textbook review, an advisory committee (N = 14), and knowledge fairs (N = 112). PSWs can participate in team-based stroke care by observing vital information about clients in their homes, coaching clients to follow care plans, assisting to implement recommendations made by other healthcare providers, and reporting client progress, challenges, needs, and preferences to the healthcare team.Conclusions: The Observe, Coach, Assist, and Report (OCAR) themes have the potential to be used as a framework to guide improvements in intra-team communication, information sharing, and awareness of the PSW role, in order to support a more integrated home care experience for clients and families. Next steps include pilot testing the OCAR framework at the point of care in various settings to enhance interdisciplinary collaboration that is inclusive of PSWs