When Do We Learn to Cooperate? The Role of Social Learning in Social Dilemmas

In this paper, I look at the interaction between social learning and cooperative behavior. I model this using a social dilemma game with publicly observed sequential actions and asymmetric information about payoffs. I find that some informed agents in this model act, individually and without collusion, to conceal the privately optimal action. Because the privately optimal action is socially costly the behavior of informed agents can lead to a Pareto improvement in a social dilemma. In my model I show that it is possible to get cooperative behavior if information is restricted to a small but non-zero proportion of the population. Moreover, such cooperative behavior occurs in a nite setting where it is public knowledge which agent will act last. The proportion of cooperative agents within the population can be made arbitrarily close to 1 by increasing the infinite number of agents playing the game. Finally, I show that under a broad set of conditions that it is a Pareto improvement on a corner value, in the ex-ante welfare sense, for an interior proportion of the population to be informed.Asymmetric information, cooperation, efficiency, social learning, social dilemmas.

A computational study of the inclusion processes of cyclodextrins and cyclodextrin polymers

Cyclodextrins (CDs) are molecules that are composed of glucopyranose rings. Cyclodextrins can be formed from either 6, 7, or 8 glucopyranose units yielding, α-, β-, or y-Cyclodextrins respectively. Cyclodextrin polymers (COPs) can occur when glyceryl linkers are added to the previously mentioned cyclodextrins. CDs and COPs are hydrophilic, yet contain a hydrophobic cavity. This cavity allows for the binding of numerous guest molecules. Some practical purposes resulting from the host-guest interactions can be seen in cosmetology, food science, and pharmacy. Using the MacroModel Interactive Molecular Modeling System Version 5.0 we studied the binding of guest molecules to α-, β-, and y-CDs and CDPs. P-nitrophenol and p-hydroxylmethyl benzoate are bound to α-CD and α-CDP, a single pyrene is bound to β-CD and β-CDP, while two pyrenes can bind to the large cavity of y-CD and y-CDP. For all three CDPs, the number of glyceryl linker unit& was systematically varied from one to ten to look at the effect of chain length on the stability of clam-shell versus open-binding. Each structure is minimized in both a clam shell conformation, with the guest surrounded by two CDs connected by glyceryl linker units and in an open conformation, with the guest bound to only one CD of the CDP. An inverted position for open binding was also studied in α-CD and α-CDP. This position occurs when the ester group of p-hydroxylmethyl benzoate and rutro group of p-nitrophenol bind to the CD or COP as opposed to the hydroxyl groups. The results obtained show that open binding is most stable for α-, β-, and y-CDPs for all chain lengths, and that there is no optimal value or glyceryl units for dam-shell binding. The determination of whether the inverted position in open binding is preferable to the normal position is inconclusive

Clear and present danger: Brandenburg test after September 11, 2001

In a post-September 11, 2001 America and in light of the very real threat posed by radical Islamic terrorist, the courts must rethink the line between protected speech and incitement to violence. The Brandenburg test, which was previously understood to be the modern test to distinguish protected from unprotected advocacy, should be questioned. By examining the development of the Court\u27s First Amendment doctrine leading up to Brandenburg v. Ohio (1969), I establish that Brandenburg is ill fitted to be applied to advocacy of terrorism. In Brandenburg, the Court actually conflated two previously distinct speech tests-Judge Learned Hand\u27s incitement test and Justice Oliver Wendell Holmes\u27 clear and present danger test-without explaining how these two tests fit together. In addition, the Court founded Brandenburg on sandy soil. The Court failed to distinguish between the two traditions. They cited Hand\u27s incitement tradition as precedent for the clear and present danger test. In doing so, they credited Brandenburg\u27s imminence requirement to Hand\u27s direct incitement tradition, which did not include an imminence requirement. Therefore, Brandenburg should be abandoned. I conclude that the courts should apply the clear and present danger test and the direct incitement test separately according to the particular circumstances of each case. I will give two modern examples of advocacy of terrorism. I will show how the courts would be better off applying the clear and present danger test as developed by Holmes and Brandeis in one case and the direct incitement test as developed in by Judge Hand in the other. By taking a two test approach to advocacy of terrorism, the government will better posses the tools it needs to protect national security

Recovery and desistance : what the emerging recovery movement in the alcohol and drug area can learn from models of desistance from offending

In the last twenty years, the recovery movement in alcohol and other drugs (AOD) has emerged as a major influence on alcohol and drug policy and practice in the UK, US and Australia. In roughly the same period of time, the desistance movement has become increasingly prominent in academic criminology, and is increasingly influential in criminal justice practice, particularly in the area of probation. Furthermore, the populations involved in recovery and desistance research have significant overlap, yet there has been little shared learning across these areas. The current article explores the evolution of thinking around desistance and what lessons it might offer conceptual models of recovery. It will be argued that one of the most important shared assumptions relates to identity change, and the extent to which these identity changes are intrinsically social or 'relational'. The paper will advance a social identity model as a mechanism for understanding the journey to recovery or desistance and the centrality of reintegration into communities for a coherent model and public policy around addiction recovery

Predicting success with silicone-hydrogel contact lenses in new wearers

Purpose: to evaluate changes in tear metrics and ocular signs induced by six months of silicone-hydrogel contact lens wear and the difference in baseline characteristics between those who successfully continued in contact lens wear compared to those that did not. Methods: Non-invasive Keratograph, Tearscope and fluorescein tear break-up times (TBUTs), tear meniscus height, bulbar and limbal hyperaemia, lid-parallel conjunctival folds (LIPCOF), phenol red thread, fluorescein and lissamine-green staining, and lid wiper epitheliopathy were measured on 60 new contact lens wearers fitted with monthly silicone-hydrogels (average age 36 ± 14 years, 40 females). Symptoms were evaluated by the Ocular Surface Disease Index (OSDI). After six months full time contact lens wear the above metrics were re-measured on those patients still in contact lens wear (n= 33). The initial measurements were also compared between the group still wearing lenses after six months and those who had ceased lens wear (n= 27). Results: There were significant changes in tear meniscus height (p= 0.031), bulbar hyperaemia (p= 0.011), fluorescein TBUT (p= 0.027), corneal (p= 0.007) and conjunctival (p= 0.009) staining, LIPCOF (p= 0.011) and lid wiper epitheliopathy (p= 0.002) after six months of silicone-hydrogel wear. Successful wearers had a higher non-invasive (17.0 ± 8.2. s vs 12.0 ± 5.6. s; p= 0.001) and fluorescein (10.7 ± 6.4. s vs 7.5 ± 4.7. s; p= 0.001) TBUT than drop-outs, although OSDI (cut-off 4.2) was also a strong predictor of success. Conclusion: Silicone-hydrogel lenses induced significant changes in the tear film and ocular surface as well as lid margin staining. Wettability of the ocular surface is the main factor affecting contact lens drop-out. © 2013 British Contact Lens Association

Systems Medicine Disease: Disease Classification and Scalability Beyond Networks and Boundary Conditions

In order to accommodate the forthcoming wealth of health and disease related information, from genome to body sensors to population and the environment, the approach to disease description and definition demands re-examination. Traditional classification methods remain trapped by history; to provide the descriptive features that are required for a comprehensive description of disease, systems science, which realizes dynamic processes, adaptive response, and asynchronous communication channels, must be applied (Wolkenhauer et al., 2013). When Disease is viewed beyond the thresholds of lines and threshold boundaries, disease definition is not only the result of reductionist, mechanistic categories which reluctantly face re-composition. Disease is process and synergy as the characteristics of Systems Biology and Systems Medicine are included. To capture the wealth of information and contribute meaningfully to medical practice and biology research, Disease classification goes beyond a single spatial biologic level or static time assignment to include the interface of Disease process and organism response (Bechtel, 2017a; Green et al., 2017)

Life in recovery: a families’ perspective

Although the Life in Recovery series has provided valuable insights into the transformation of the lives of people in recov- ery and has helped to frame that by recovery method and approach, by gender and by location, it has not assessed the impact of recovery on those immediately surrounding the person in recovery. The Families Living in Addiction and Recovery (FLAR) survey was an attempt to address this by inviting family members to report on their experiences, as witnesses and in their own right as people going through their own version of recovery. Based on two half-day work- shops in London and Sheffield, a revised survey for family members was developed that assessed the family member ’ s observations of recovery and their own personal journey. In total, 1,565 surveys were completed and returned, reflecting much of the positive experience of the previous surveys. They also showed the extent of adverse effects of addiction and the subsequent benefits of recovery to family members. However, recovery is not a linear process, and much of the data in this article discusses the impact of user relapse on family member functioning. The implications for ongoing support for family members and further research around the recovery journeys of family members are discussed

The influence of flow discharge variations on the morphodynamics of a diffluence-confluence unit on a large river: Impacts of discharge variation on a diffluence-confluence unit

© 2017 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd. Bifurcations are key geomorphological nodes in anabranching and braided fluvial channels, controlling local bed morphology, the routing of sediment and water, and ultimately defining the stability of their associated diffluence–confluence unit. Recently, numerical modelling of bifurcations has focused on the relationship between flow conditions and the partitioning of sediment between the bifurcate channels. Herein, we report on field observations spanning September 2013 to July 2014 of the three-dimensional flow structure, bed morphological change and partitioning of both flow discharge and suspended sediment through a large diffluence–confluence unit on the Mekong River, Cambodia, across a range of flow stages (from 13 500 to 27 000 m 3 s −1 ). Analysis of discharge and sediment load throughout the diffluence–confluence unit reveals that during the highest flows (Q = 27 000 m 3 s −1 ), the downstream island complex is a net sink of sediment (losing 2600 ± 2000 kg s −1 between the diffluence and confluence), whereas during the rising limb (Q = 19 500 m 3 s −1 ) and falling limb flows (Q = 13 500 m 3 s −1 ) the sediment balance is in quasi-equilibrium. We show that the discharge asymmetry of the bifurcation varies with discharge and highlight that the influence of upstream curvature-induced water surface slope and bed morphological change may be first-order controls on bifurcation configuration. Comparison of our field data to existing bifurcation stability diagrams reveals that during lower (rising and falling limb) flow the bifurcation may be classified as unstable, yet transitions to a stable condition at high flows. However, over the long term (1959–2013) aerial imagery reveals the diffluence–confluence unit to be fairly stable. We propose, therefore, that the long-term stability of the bifurcation, as well as the larger channel planform and morphology of the diffluence–confluence unit, may be controlled by the dominant sediment transport regime of the system. © 2017 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd