Bidding Games on Markov Decision Processes

In two-player games on graphs, the players move a token through a graph to produce an infinite path, which determines the qualitative winner or quantitative payoff of the game. In bidding games, in each turn, we hold an auction between the two players to determine which player moves the token. Bidding games have largely been studied with concrete bidding mechanisms that are variants of a first-price auction: in each turn both players simultaneously submit bids, the higher bidder moves the token, and pays his bid to the lower bidder in Richman bidding, to the bank in poorman bidding, and in taxman bidding, the bid is split between the other player and the bank according to a predefined constant factor. Bidding games are deterministic games. They have an intriguing connection with a fragment of stochastic games called randomturn games. We study, for the first time, a combination of bidding games with probabilistic behavior; namely, we study bidding games that are played on Markov decision processes, where the players bid for the right to choose the next action, which determines the probability distribution according to which the next vertex is chosen. We study parity and meanpayoff bidding games on MDPs and extend results from the deterministic bidding setting to the probabilistic one

A Multicomponent eHealth Intervention for Family Carers for People Affected by Psychosis: A Coproduced Design and Build Study

Background: Psychosis, including schizophrenia, is the most common severe mental illness affecting 1% of the population worldwide. A large number of people provide long-term support and care for a relative with psychosis. Although psychoeducational interventions, especially those delivered through a face-to-face group format, have an established evidence base for improving the caregiving experience, well-being, and health outcomes, large-scale implementation and access remain limited. There is a demand for such provision to be made through the internet for greater flexibility and wider access. Objective: This study aimed to integrate participatory research methodologies by the public, patients, and carers into the eHealth (electronic health) intervention design and build process to improve the product’s usability and acceptability. Methods: We adapted a structured eHealth intervention build method to include participatory research activities involving key stakeholders and end users to co-design and coproduce our intervention. An expert advisory group (EAG) comprising public involvement members led the formative design and build work using an agile build process. Carers independent from the study were consulted on the evolving drafts of the intervention prototype through focus group meetings. These results were fed back into the intervention build work continuously to ensure end users’ input inform every stage of the process. Results: An EAG comprising individuals with lived experience of psychosis, carers, health care professionals, researchers, voluntary organization workers, and eLearning experts (n=14) was established. A total of 4 coproduction workshops were held over 1 year during which the alpha and beta prototypes were designed and built through the participatory research work. Alongside this, 2 rounds of focus group study with carers (n=24, in 4 groups) were conducted to seek consultation on end users’ views and ideas to optimize the intervention design and usability. Finally, the EAG carried out a Web-based walk-through exercise on the intervention prototype and further refined it to make it ready for an online usability test. The final product contains multiple sections providing information on psychosis and related caregiving topics and interactive discussion forums with experts and peers for psychosocial support. It provides psychoeducation and psychosocial support for carers through the internet, promoting flexible access and individualized choices of information and support. Conclusions: The participatory research work led to the coproduction of a eHealth intervention called COPe-support (Carers fOr People with Psychosis e-support). We believe the study methodology, results, and output have optimized the intervention design and usability, fitting the end users’ needs and usage pattern. COPe-support is currently being tested for its effectiveness in promoting carers’ health outcome through an online randomized controlled trial. Trial Registration: ISRCTN Registry ISRCTN89563420; http://www.isrctn.com/ISRCTN8956342

Observations of the lunar plasma wake from the WIND spacecraft on December 27, 1994

On December 27, 1994, the WIND spacecraft crossed the lunar wake at a distance of 6.5 lunar radii ( RL ) behind the moon. The observations made were the first employing modem instruments and a high data rate. The SWE plasma instrument on WIND observed new aspects of the interaction between the solar wind and unmagnetized dielectric bodies. The plasma density decreased exponentially from the periphery of the wake towards its center as predicted by simple theory. Behind the moon two distinct cold ion beams were observed refilling the lunar cavity. The ions were accelerated along the direction of the magnetic field by an electric field of the order 2 × 10−4 volts/m. The region of plasma depletion was observed to extend beyond the light shadow, consistent with a rarefaction wave moving out from the wake into the undisturbed solar wind

The long-term prediction of return to work following serious accidental injuries: A follow up study

Background Considerable indirect costs are incurred by time taken off work following accidental injuries. The aim of this study was to predict return to work following serious accidental injuries. Method 121 severely injured patients were included in the study. Complete follow-up data were available for 85 patients. Two weeks post trauma (T1), patients rated their appraisal of the injury severity and their ability to cope with the injury and its job-related consequences. Time off work was assessed at one (T2) and three years (T3) post accident. The main outcome was the number of days of sick leave taken due to the accidental injury. Results The patients' appraisals a) of the injury severity and b) of their coping abilities regarding the accidental injury and its job-related consequences were significant predictors of the number of sick-leave days taken. Injury severity (ISS), type of accident, age and gender did not contribute significantly to the prediction. Conclusions Return to work in the long term is best predicted by the patients' own appraisal of both their injury severity and the ability to cope with the accidental injury

Infinite-Duration Poorman-Bidding Games

In two-player games on graphs, the players move a token through a graph to produce an infinite path, which determines the winner or payoff of the game. Such games are central in formal verification since they model the interaction between a non-terminating system and its environment. We study bidding games in which the players bid for the right to move the token. Two bidding rules have been defined. In Richman bidding, in each round, the players simultaneously submit bids, and the higher bidder moves the token and pays the other player. Poorman bidding is similar except that the winner of the bidding pays the “bank” rather than the other player. While poorman reachability games have been studied before, we present, for the first time, results on infinite-duration poorman games. A central quantity in these games is the ratio between the two players’ initial budgets. The questions we study concern a necessary and sufficient ratio with which a player can achieve a goal. For reachability objectives, such threshold ratios are known to exist for both bidding rules. We show that the properties of poorman reachability games extend to complex qualitative objectives such as parity, similarly to the Richman case. Our most interesting results concern quantitative poorman games, namely poorman mean-payoff games, where we construct optimal strategies depending on the initial ratio, by showing a connection with random-turn based games. The connection in itself is interesting, because it does not hold for reachability poorman games. We also solve the complexity problems that arise in poorman bidding games

The E Sibling Project - exploratory randomised controlled trial of an online multi-component psychoeducational intervention for siblings of individuals with first episode psychosis

Background:Siblings of individuals with first episode psychosis are natural partners to promote service users’recovery and are themselves vulnerable to mental ill health due to the negative impact of psychosis withinthe family. This study aims to develop and undertake a preliminary evaluation of the efficacy of an onlinemulti-component psychoeducational intervention for siblings of individuals with first episode psychosis. Theimpetus for the intervention arose from siblings' expressed needs for peer support and information on psychosis,coping and management strategies for common symptoms and ways to promote recovery. Methods/Design:The project design draws on the Medical Research Council framework for the design andevaluation of complex interventions. Mixed methods comprising collection of qualitative focus group data,systematic review and expert advisory group consultation are used to develop the theoretical basis for and designof the intervention. This protocol focuses on the modelling and piloting phase which uses a randomised controlledtrial with factorial design to test the efficacy of the intervention. Outcome data on participants’mental wellbeing,knowledge, perceived self-efficacy and experiences of caregiving will be assessed at baseline, at end of theintervention (10 weeks later) and at 10 week follow-up. In addition, a post-intervention semi-structured interviewwith 20% of the participants will explore their experiences and acceptability of the intervention. Discussion:This multi-component online psychoeducational intervention aims to enhance siblings' knowledgeabout psychosis and their coping capacity, thus potentially improving their own mental wellbeing and promotingtheir contribution to service users’recovery. The factorial design randomised controlled trial with a supplementaryprocess evaluation using semi-structured interviews and usage-monitoring will collect preliminary evidence ofefficacy, feasibility and acceptability, as well as feedback about the barriers and strategies to using such aninnovative resource. The RCT will provide data for estimating the likely effect size of the intervention on outcomesfor siblings and inform the development of a definitive future trial

Cryptosporidium Priming Is More Effective than Vaccine for Protection against Cryptosporidiosis in a Murine Protein Malnutrition Model

Cryptosporidium is a major cause of severe diarrhea, especially in malnourished children. Using a murine model of C. parvum oocyst challenge that recapitulates clinical features of severe cryptosporidiosis during malnutrition, we interrogated the effect of protein malnutrition (PM) on primary and secondary responses to C. parvum challenge, and tested the differential ability of mucosal priming strategies to overcome the PM-induced susceptibility. We determined that while PM fundamentally alters systemic and mucosal primary immune responses to Cryptosporidium, priming with C. parvum (106 oocysts) provides robust protective immunity against re-challenge despite ongoing PM. C. parvum priming restores mucosal Th1-type effectors (CD3+CD8+CD103+ T-cells) and cytokines (IFNγ, and IL12p40) that otherwise decrease with ongoing PM. Vaccination strategies with Cryptosporidium antigens expressed in the S. Typhi vector 908htr, however, do not enhance Th1-type responses to C. parvum challenge during PM, even though vaccination strongly boosts immunity in challenged fully nourished hosts. Remote non-specific exposures to the attenuated S. Typhi vector alone or the TLR9 agonist CpG ODN-1668 can partially attenuate C. parvum severity during PM, but neither as effectively as viable C. parvum priming. We conclude that although PM interferes with basal and vaccine-boosted immune responses to C. parvum, sustained reductions in disease severity are possible through mucosal activators of host defenses, and specifically C. parvum priming can elicit impressively robust Th1-type protective immunity despite ongoing protein malnutrition. These findings add insight into potential correlates of Cryptosporidium immunity and future vaccine strategies in malnourished children

HIV-related travel restrictions: trends and country characteristics

Introduction: Increasingly, HIV-seropositive individuals cross international borders. HIV-related restrictions on entry, stay, and residence imposed by countries have important consequences for this mobile population. Our aim was to describe the geographical distribution of countries with travel restrictions and to examine the trends and characteristics of countries with such restrictions. Methods: In 2011, data presented to UNAIDS were used to establish a list of countries with and without HIV restrictions on entry, stay, and residence and to describe their geographical distribution. The following indicators were investigated to describe the country characteristics: population at mid-year, international migrants as a percentage of the population, Human Development Index, estimated HIV prevalence (age: 15–49), presence of a policy prohibiting HIV screening for general employment purposes, government and civil society responses to having non-discrimination laws/regulations which specify migrants/mobile populations, government and civil society responses to having laws/regulations/policies that present obstacles to effective HIV prevention, treatment, care, and support for migrants/mobile populations, Corruption Perception Index, and gross national income per capita. Results: HIV-related restrictions exist in 45 out of 193 WHO countries (23%) in all regions of the world. We found that the Eastern Mediterranean and Western Pacific Regions have the highest proportions of countries with these restrictions. Our analyses showed that countries that have opted for restrictions have the following characteristics: smaller populations, higher proportions of migrants in the population, lower HIV prevalence rates, and lack of legislation protecting people living with HIV from screening for employment purposes, compared with countries without restrictions. Conclusion: Countries with a high proportion of international migrants tend to have travel restrictions – a finding that is relevant to migrant populations and travel medicine providers alike. Despite international pressure to remove travel restrictions, many countries continue to implement these restrictions for HIV-positive individuals on entry and stay. Since 2010, the United States and China have engaged in high profile removals. This may be indicative of an increasing trend, facilitated by various factors, including international advocacy and the setting of a UNAIDS goal to halve the number of countries with restrictions by 2015