Global payoff uncertainty and risk dominance

Choice Theory

Global games and equilibrium selection

Game Theory;Equilibrium Theory

Equilibrium selection in stag hunt games

Game Theory

A self-regulation perspective on avoidance and persistence behaviour in chronic pain: new theories, new challenges?

Objective: Behavioral factors such as avoidance and persistence have received massive theoretical and empirical attention in the attempts to explain chronic pain and disability. The determinants of these pain behaviors remain, however, poorly understood. We propose a self-regulation perspective to increase our understanding of pain-related avoidance and persistence. Methods: A narrative review. Results: We identified several theoretical views that may help explaining avoidance and persistence behavior, and organized these views around 4 concepts central in self-regulation theories: (1) identity, (2) affective-motivational orientation, (3) goal cognitions, and (4) coping. The review shows that each of these self-regulation perspectives allows for a broadened view in which pain behaviors are not simply considered passive consequences of fear, but proactive strategies to regulate the self when challenged by pain. Discussion: Several implications and challenges arising from this review are discussed. In particular, a self-regulation perspective does not consider avoidance and persistence behavior to be intrinsically adaptive or maladaptive, but argues that their effects on disability and well-being rather depend on the goals underlying these behaviors. Such view would require a shift in how avoidance and persistence behavior are assessed and approached in clinical interventions

Standardising the clinical assessment of coronal knee laxity

Clinical laxity tests are used for assessing knee ligament injuries and for soft tissue balancing in total knee arthroplasty. This study reports the development and validation of a quantitative technique of assessing collateral knee laxity through accurate measurement of potential variables during routine clinical examination. The hypothesis was that standardisation of a clinical stress test would result in a repeatable range of laxity measurements.Non- invasive infrared tracking technology with kinematic registration of joint centres gave real-time measurement of both coronal and sagittal mechanical tibiofemoral alignment. Knee flexion, moment arm and magnitude of the applied force were all measured and standardised. Three clinicians then performed six knee laxity examinations on a single volunteer using a target moment of 18Nm. Standardised laxity measurements had small standard deviations (within 1.1°) for each clinician and similar mean values between clinicians, with the valgus laxity assessment (mean of 3°) being slightly more consistent than varus (means of 4° or 5°).The manual technique of coronal knee laxity assessment was successfully quantified and standardised, leading to a narrow range of measurements (within the accuracy of the measurement system). Minimising the subjective variables of clinical examination could improve current knowledge of soft tissue knee behaviour

Gynodioecy in <i>Plantago lanceolata</i>:VI. Functions of cytokinins in growth, development, and reproduction of two sex types

Theoretical models predict that male sterile plants of gynodioecious species should show at least some compensation for their disadvantage of not reproducing as males through female component of fitness. In this study, growth, development, and reproduction of a hermaphrodite and a male sterile family of Plantago lanceolata L. were compared under controlled conditions. The male sterile plants produced more and longer spikes and had relatively longer styles. The male sterile plants achieved their final biomass sooner, by an earlier formation of side rosettes, and flowered earlier. The hypothesis was tested as to whether cytokinins in the plants are involved as a pleiotropic factor in either or both sex expression and the various plant characteristics associated with the male sterile phenotype. The roots of the male sterile plants had higher concentrations of putative zeatin riboside than the roots of the hermaphroditic plants, as quantified by an enzyme-linked immunoassy after separation of cytokinins by high performance liquid chromatography. Spraying the plants with benzyladenine did not affect internal cytokinin concentrations or sex expression. Benzyladenine spray increased the growth rate of the main rosette and stimulated floral initiation. Our results indicate that cytokinins are possibly involved in determining the morphological differences between sex types in this species