Project description:Predation risk can alter female mating decisions because the costs of mate searching and selecting attractive mates increase when predators are present. In response to predators, females have been found to plastically adjust mate preference within species, but little is known about how predators alter sexual isolation and hybridization among species. We tested the effects of predator exposure on sexual isolation between benthic and limnetic threespine sticklebacks (Gasterosteus spp.). Female discrimination against heterospecific mates was measured before and after females experienced a simulated attack by a trout predator or a control exposure to a harmless object. In the absence of predators, females showed increased aversion to heterospecifics over time. We found that predator exposure made females less discriminating and precluded this learned aversion to heterospecifics. Benthic and limnetic males differ in coloration, and predator exposure also affected sexual isolation by weakening female preferences for colourful males. Predator effects on sexual selection were also tested but predators had few effects on female choosiness among conspecific mates. Our results suggest that predation risk may disrupt the cognitive processes associated with mate choice and lead to fluctuations in the strength of sexual isolation between species.
Project description:ObjectiveTo describe rank reversal as a source of inconsistent interpretation intrinsic to indirect comparison (Bucher HC, Guyatt GH, Griffith LE, Walter SD. The results of direct and indirect treatment comparisons in meta-analysis of randomized controlled trials. J Clin Epi 1997;50:683-91) of treatments and to propose best practice.MethodsWe prove our main points with intuition, examples, graphs, and mathematical proofs. We also provide software and discuss implications for research and policy.ResultsWhen comparing treatments by indirect means and sorting them by effect size, three common measures of comparison (risk ratio, risk difference, and odds ratio) may lead to vastly different rankings.ConclusionsThe choice of risk measure matters when making indirect comparisons of treatments. The choice should depend primarily on the study design and the conceptual framework for that study.
Project description:Antiviral agents have been hailed to hold considerable promise for the treatment and prevention of emerging viral diseases like H5N1 avian influenza and SARS. However, antiviral drugs are not completely harmless, and the conditions under which individuals are willing to participate in a large-scale antiviral drug treatment program are as yet unknown. We provide population dynamical and game theoretical analyses of large-scale prophylactic antiviral treatment programs. Throughout we compare the antiviral control strategy that is optimal from the public health perspective with the control strategy that would evolve if individuals make their own, rational decisions. To this end we investigate the conditions under which a large-scale antiviral control program can prevent an epidemic, and we analyze at what point in an unfolding epidemic the risk of infection starts to outweigh the cost of antiviral treatment. This enables investigation of how the optimal control strategy is moulded by the efficacy of antiviral drugs, the risk of mortality by antiviral prophylaxis, and the transmissibility of the pathogen. Our analyses show that there can be a strong incentive for an individual to take less antiviral drugs than is optimal from the public health perspective. In particular, when public health asks for early and aggressive control to prevent or curb an emerging pathogen, for the individual antiviral drug treatment is attractive only when the risk of infection has become non-negligible. It is even possible that from a public health perspective a situation in which everybody takes antiviral drugs is optimal, while the process of individual choice leads to a situation where nobody is willing to take antiviral drugs.
Project description:The transcription factor MYB plays a pivotal role in haematopoietic homoeostasis and its aberrant expression is involved in the genesis and maintenance of acute myeloid leukaemia (AML). We have previously demonstrated that not all AML subtypes display the same dependency on MYB expression and that such variability is dictated by the nature of the driver mutation. However, whether this difference in MYB dependency is a general trend in AML remains to be further elucidated. Here, we investigate the role of MYB in human leukaemia by performing siRNA-mediated knock-down in cell line models of AML with different driver lesions. We show that the characteristic reduction in proliferation and the concomitant induction of myeloid differentiation that is observed in MLL-rearranged and t(8;21) leukaemias upon MYB suppression is not seen in AML cells with a complex karyotype. Transcriptome analyses revealed that MYB ablation produces consensual increase of MAFB expression in MYB-dependent cells and, interestingly, the ectopic expression of MAFB could phenocopy the effect of MYB suppression. Accordingly, in silico stratification analyses of molecular data from AML patients revealed a reciprocal relationship between MYB and MAFB expression, highlighting a novel biological interconnection between these two factors in AML and supporting new rationales of MAFB targeting in MLL-rearranged leukaemias.
Project description:The recent threat of bioterrorism has fueled debate on smallpox vaccination policy for the United States. Certain policy proposals call for voluntary mass vaccination; however, if individuals decide whether to vaccinate according to self-interest, the level of herd immunity achieved may differ from what is best for the population as a whole. We present a synthesis of game theory and epidemic modeling that formalizes this conflict between self-interest and group interest and shows that voluntary vaccination is unlikely to reach the group-optimal level. This shortfall results in a substantial increase in expected mortality after an attack.
Project description:Does stepping back to evaluate a situation from a distanced perspective lead us to be selfish or fair? This question has been of philosophical interest for centuries, and, more recently, the focus of extensive empirical inquiry. Yet, extant research reveals a puzzle: some studies suggest that adopting a distanced perspective will produce more rationally self-interested behavior, whereas others suggest that it will produce more impartial behavior. Here we adjudicate between these perspectives by testing the effects of adopting a third-person perspective on decision making in a task that pits rational self-interest against impartiality: the dictator game. Aggregating across three experiments (N = 774), participants who used third-person (i.e., distanced) vs. first-person (i.e., immersed) self-talk during the dictator game kept more money for themselves. We discuss these results in light of prior research showing that psychological distance can promote cooperation and fairmindedness and how the effect of psychological distance on moral decision-making may be sensitive to social context.
Project description:Spatial sign and rank-based methods have been studied in the recent literature, especially when the dimension is smaller than the sample size. In this paper, a classification method based on the distribution of rank functions for high-dimensional data is considered with extension to functional data. The method is fully nonparametric in nature. The performance of the classification method is illustrated in comparison with some other classifiers using simulated and real data sets. Supporting code in R are provided for computational implementation of the classification method that will be of use to others.
Project description:BackgroundAversive conditioning weakens the gratifying value of a comfort meal. The aim was to determine the effect of a cognitive intervention to reverse aversive conditioning and restore hedonic postprandial response.MethodsThis was a randomized, sham-controlled, single-blind, parallel study that was conducted on 12 healthy women (n = 6 in each group). The reward value of a comfort meal was measured on different days: at initial exposure, after aversive conditioning (administration of the same meal with a masked fat overload on the previous day) and after a cognitive intervention (disclosing the aversive conditioning paradigm in the test group vs. no explanation in the control group). The primary outcome, digestive wellbeing, was determined using graded scales at regular intervals before and after ingestion.ResultsAt initial exposure, the comfort meal produced a rewarding experience that was impaired using aversive conditioning; upon re-exposure to the original meal, the cognitive intervention increased meal wanting and liking; improved digestive wellbeing and mood; tended to reduce postprandial satiety, bloating/fullness; and abolished discomfort/pain, thereby restoring the hedonic value of the comfort meal. By contrast, sham intervention had no effects, and the postprandial sensations remained like the responses to the offending meal.ConclusionIn this proof-of-concept study, we demonstrate that in healthy women, a mild, short-term acquired aversion to a comfort meal can be reversed using a cognitive intervention.Clinicaltrialsgov ID: NCT05897411.
Project description:Altruism and the medical profession have been linked throughout the history of medicine. Students are drawn to the calling of medicine because of altruistic values, dedication to service, and the desire to alleviate suffering and promote healing. Despite a dedication to these values, altruism in medicine is threatened by empathy erosion that develops in the clinical years of medical school and an increasing rate of medical student burnout. Currently, there are two widespread movements in medicine aimed at addressing the dual loss of altruism and physician and student burnout-professionalism and wellness. Despite widespread recognition of the problems and programs aimed at improving them, there has been little headway, and even calls to abandon altruism in the modern marketplace of medicine. What is needed is not an abandonment of a fundamental, defining value of the profession, but a re-evaluation of the meaning of altruism in medicine and a framework that allows for students and physicians to provide altruistic care for a sustainable, rewarding career in the healing profession. This paper proposes the Enlightened Self-Interest in Altruism (ESIA) model as an ethical framework to allow medical students to synergize the interests of the self with those they serve in a mutually beneficial relationship to improve patient care and the healthcare system at large. The ESIA model acknowledges that egoism and altruism are intertwined, dynamic motivators of behavior. In the enlightened self-interest approach, the interests of the group are also the interests of the self. The physician-patient relationship is a dyad in which egoism and altruism may converge in an enlightened way that acknowledges that the interests of one are the interests of the whole. This is a paradigm shift from the historical view of egoism and altruism as opposing motivations. This paper will present the threats to altruism, explore the interface of egoism and altruism in a clinical vignette, and then present the ESIA framework as an educational approach to aligning the interests of providers and patients to prevent burnout and promote altruism.
Project description:BackgroundAltruism refers to acting in 'the best interest of patients, not self-interest'. With an observed discordance between the concept and practice of altruism, and increasing attention to 'pathologic altruism', the role of altruism is blurred in present day medical care. In this background, the required balance of altruistic attitude which needs to be fostered in medical students needs clarity. This problem may be best addressed by the practicing clinicians. The objectives of this study were to explore clinicians' understanding of altruism in the clinical context and to identify the key concepts of altruism which they felt, must be included in clinical practice.MethodsIt was an exploratory qualitative study to identify clinicians' understanding of altruism and the key practice points for altruism. Online semi-structured interviews were conducted from 18 clinicians through Zoom and transcribed using Otter. Open coding of interview transcripts was done using Atlas ti 8 and grouped by commonalities under sub themes and themes.ResultsThe main concepts regarding the clinicians' understanding of altruism were prioritizing patients' interest above oneself, favouring patients beyond routine duty and organized team work for practicing altruism. The essential practice areas identified for altruism were finding a balance between altruistic tendency and self/family life, identifying one's individual capacity for altruism, establishing teamwork for developing a workplace altruistic attitude, and facilitating patients beyond routine duty.ConclusionsAltruism is an important professionalism attribute for clinicians, however prioritizing patients interest requires a balanced approach so that it is effective and sustainable. Workplace altruistic cultures may be better promoted through organized team-based approach rather than individual efforts.