Quantum paradox of choice: More freedom makes summoning a quantum state harder

The properties of quantum information in space-time can be investigated by studying operational tasks. In one such task, summoning, an unknown quantum state is supplied at one point, and a call is made at another for it to be returned at a third. Hayden-May recently proved necessary and sufficient conditions for guaranteeing successful return of a summoned state for finite sets of call and return points when there is a guarantee of at most one summons. We prove necessary and sufficient conditions when there may be several possible summonses and complying with any one constitutes success. We show there is a "quantum paradox of choice" in summoning: the extra freedom in completing the task makes it strictly harder. This intriguing result has practical applications for distributed quantum computing and cryptography and also implications for our understanding of relativistic quantum information and its localization in space-time.This work was partially supported by an FQXi grant and by Perimeter Institute for Theoretical Physics. Research at Perimeter Institute is supported by the Government of Canada through Industry Canada and by the Province of Ontario through the Ministry of Research and Innovation.This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by the American Physical Society

Universality of fixation probabilities in randomly structured populations

The stage of evolution is the population of reproducing individuals. The structure of the population is known to affect the dynamics and outcome of evolutionary processes, but analytical results for generic random structures have been lacking. The most general result so far, the isothermal theorem, assumes the propensity for change in each position is exactly the same, but realistic biological structures are always subject to variation and noise. We consider a finite population under constant selection whose structure is given by a variety of weighted, directed, random graphs; vertices represent individuals and edges interactions between individuals. By establishing a robustness result for the isothermal theorem and using large deviation estimates to understand the typical structure of random graphs, we prove that for a generalization of the Erdős-Rényi model, the fixation probability of an invading mutant is approximately the same as that of a mutant of equal fitness in a well-mixed population with high probability. Simulations of perturbed lattices, small-world networks, and scale-free networks behave similarly. We conjecture that the fixation probability in a well-mixed population, (1 − r−1)/(1 − r−n), is universal: for many random graph models, the fixation probability approaches the above function uniformly as the graphs become large

Temporal and spatial variation in active layer depth in the McMurdo Sound Region, Antarctica

A soil climate monitoring network, consisting of seven automated weather stations, was established between 1999 and 2003, ranging from Minna Bluff to Granite Harbour and from near sea level to about 1700m on the edge of the polar plateau. Active layer depth was calculated for each site for eight successive summers from 1999/2000 to 2006/2007. The active layer depth varied from year to year and was deepest in the warm summer of 2001–02 at all recording sites. No trends of overall increase or decrease in active layer depth were evident across the up-to-eight years of data investigated. Average active layer depth decreased with increasing latitude from Granite Harbour (778S, active layer depth of.90 cm) to Minna Bluff (78.58S, active layer depth of 22 ± 0.4 cm), and decreased with increasing altitude from Marble Point (50m altitude, active layer depth of 49 ± 9 cm) through to Mount Fleming (1700m altitude, active layer depth of 6 ± 2 cm). When all data from the sites were grouped together and used to predict active layer depth the mean summer air temperature, mean winter air temperature, total summer solar radiation and mean summer wind speed explained 73% of the variation (R250.73)

A Systematic Review of Neuropsychological Rehabilitation for Prospective Memory Deficits as a Consequence of Acquired Brain Injury

AcceptedArticleThis is the author accepted manuscript. The final version is available from Cambridge University Press via the DOI in this record.Objective: Prospective memory (PM) impairments are common following acquired brain injury (ABI). PM is the ability to keep a goal in mind for future action and interventions have the potential to increase independence. This review aimed to evaluate studies examining PM rehabilitation approaches in adults and children with ABI. Method: Relevant literature was identified using PsycARTICLES (1894 to present), PsycINFO (1880 to present), the Cochrane Library (1972 to present), MEDLINE PubMed, reference lists from relevant journal articles, and searches of key journals. Literature searches were conducted using variants of the terms brain injury, stroke, encephalitis, meningitis, and tumour, combined with variants of the terms rehabilitation and prospective memory. Results: Of the 435 papers identified, 11 were included in the review. Findings demonstrated a variety of interventions to alleviate PM deficits, including compensatory strategies (e.g., external memory aids) that provide either content-specific or content-free cueing, and remediation strategies (e.g., meta-cognitive training programmes) aimed at improving the self-monitoring of personal goals. Risk of bias for individual studies was considered and the strengths and limitations of each of the included studies and the review itself were discussed. Conclusions: Interventions utilised with adults can be effective; PM abilities can be improved by utilising simple reminder systems and performance can be generalised to facilitate everyday PM functioning. There is, however, a lack of research of PM interventions conducted with children with ABI, and paediatric interventions need to consider on-going cognitive maturation

The Academic Outcomes of Working Memory and Metacognitive Strategy Training in Children: A Double-Blind Randomised Controlled Trial

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.Working memory training has been shown to improve performance on untrained working memory tasks in typically developing children, at least when compared to nonadaptive training; however, there is little evidence that it improves academic outcomes. The lack of transfer to academic outcomes may be because children are only learning skills and strategies in a very narrow context, which they are unable to apply to other tasks. Metacognitive strategy interventions, which promote metacognitive awareness and teach children general strategies that can be used on a variety of tasks, may be a crucial missing link in this regard. In this double-blind randomised controlled trial, 95 typically developing children aged 9-14 years were allocated to three cognitive training programmes that were conducted daily after-school. One group received Cogmed working memory training, another group received concurrent Cogmed and metacognitive strategy training, and the control group received adaptive visual search training, which better controls for expectancy and motivation than non-adaptive training. Children were assessed on four working memory tasks, reading comprehension, and mathematical reasoning before, immediately after, and three months after training. Working memory training improved working memory and mathematical reasoning relative to the control group. The improvements in working memory were maintained three months later and these were significantly greater for the group that received metacognitive strategy training, compared to working memory training alone. Working memory training is a potentially effective educational intervention when provided in addition to school; however, future research will need to investigate ways to maintain academic improvements long-term and to optimise metacognitive strategy training to promote fartransfer.Economic and Social Research Council (ESRC

The Time Scale of Evolutionary Innovation

A fundamental question in biology is the following: what is the time scale that is needed for evolutionary innovations? There are many results that characterize single steps in terms of the fixation time of new mutants arising in populations of certain size and structure. But here we ask a different question, which is concerned with the much longer time scale of evolutionary trajectories: how long does it take for a population exploring a fitness landscape to find target sequences that encode new biological functions? Our key variable is the length, of the genetic sequence that undergoes adaptation. In computer science there is a crucial distinction between problems that require algorithms which take polynomial or exponential time. The latter are considered to be intractable. Here we develop a theoretical approach that allows us to estimate the time of evolution as function of We show that adaptation on many fitness landscapes takes time that is exponential in even if there are broad selection gradients and many targets uniformly distributed in sequence space. These negative results lead us to search for specific mechanisms that allow evolution to work on polynomial time scales. We study a regeneration process and show that it enables evolution to work in polynomial time

Behavioural activation written self-help to improve mood, wellbeing and quality of life in people with dementia supported by informal carers (PROMOTE): study protocol for a single-arm feasibility study.

Background: Increases in life expectancy have resulted in a global rise in dementia prevalence. Dementia is associated with poor wellbeing, low quality of life and increased incidence of mental health difficulties such as, low mood or depression. However, currently there is limited access to evidence-based psychological interventions for people with dementia experiencing low mood and poor wellbeing. Behavioural activation-based self-help, supported by informal carers and guided by mental health professionals, may represent an effective and acceptable solution. Methods/design: The present study is a Phase II (feasibility) single-arm trial informed by the MRC Complex Interventions Research Methods Framework. Up to fifty dementia participant/informal carer dyads will be recruited from a variety of settings including primary care, dementia-specific health settings, and community outreach. People living with dementia will receive behavioural activation based self-help and be supported by their informal carer who has received training in the skills required to support the self-help approach. In turn, during the use of the intervention the informal carer will be guided by mental health professionals to help them work through the materials and problem solve any difficulties. Consistent with the objectives of feasibility studies, outcomes relating to recruitment from different settings, employment of different recruitment methods, attrition, data collection procedures, clinical delivery and acceptability of the intervention will be examined. Clinical outcomes for people with dementia (symptoms of depression and quality of life) and informal carers (symptoms of depression and anxiety, carer burden and quality of life) will be measured pretreatment and at 3 months post-treatment allocation. Discussion: This study will examine the feasibility and acceptability of a novel behavioural activation-based self-help intervention designed to promote wellbeing and improve low mood in people living with dementia, alongside methodological and procedural uncertainties associated with research-related procedures. As determined by pre-specified progression criteria, if research procedures and the new intervention demonstrate feasibility and acceptability, results will then be used to inform the design of a pilot randomised controlled trial (RCT) to specifically examine remaining methodological uncertainties associated with recruitment into a randomised controlled design.This study is collaboratively funded by Cornwall Foundation Partnership Trust, South West Peninsula Academic Health Sciences Network and the University of Exeter

Children and Adolescents' Ingroup Biases and Developmental Differences in Evaluations of Peers Who Misinform

This is the final version. Available from Frontiers Media via the DOI in this record. The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Previous developmental research shows that young children display a preference for ingroup members when it comes to who they accept information from - even when that information is false. However, it is not clear how this ingroup bias develops into adolescence, and how it affects responses about peers who misinform in intergroup contexts, which is important to explore with growing numbers of young people on online platforms. Given that the developmental span from childhood to adolescence is when social groups and group norms are particularly important, the present study took a Social Reasoning Developmental Approach. This study explored whether children and adolescents respond differently to a misinformer spreading false claims about a peer breaking COVID-19 rules, depending on (a) the group membership of the misinformer and their target and (b) whether the ingroup had a "critical" norm that values questioning information before believing it. 354 United Kingdom-based children (8-11 years old) and adolescents (12-16 years old) read about an intergroup scenario in which a peer spreads misinformation on WhatsApp about a competitor. Participants first made moral evaluations, which asked them to judge and decide whether or not to include the misinformer, with follow-up "Why?" questions to capture their reasoning. This was followed by asking them to attribute intentions to the misinformer. Results showed that ingroup preferences emerged both when participants morally evaluated the misinformer, and when they justified those responses. Participants were more likely to evaluate an ingroup compared to an outgroup misinformer positively, and more likely to accuse an outgroup misinformer of dishonesty. Adolescents attributed more positive intentions to the misinformer compared with children, with children more likely to believe an outgroup misinformer was deliberately misinforming. The critical norm condition resulted in children making more positive intentionality attributions toward an ingroup misinformer, but not an outgroup misinformer. This study's findings highlight the importance of shared group identity with a misinformer when morally evaluating and reasoning about their actions, and the key role age plays in intentionality attributions surrounding a misinformer when their intentions are ambiguous.University of Exete