The contemporary global language “extinction crisis” has been analyzed by several influential linguists using concepts from ecology. In this article we study different reaction-diffusion models to explain the dynamics of language competition. We are mainly interested in situations where one language has a status advantage compared with the other. We consider previous applications of competition models from ecology, with particular attention to the implications of the “carrying capacity” term in such models. We derive existence as well as stability conditions for (...) the equilibria of the models considered, and show that depending on environmental conditions both situations—coexistence of competing languages or extinction of the less advantageous language—are possible. (shrink)

In resistance training, the use of predicting proximity to momentary task failure, and repetitions in reserve scales specifically, is a growing approach to monitoring and controlling effort. However, its validity is reliant upon accuracy in the ability to predict MF which may be affected by congruence of the perception of effort compared with the actual effort required. The present study examined participants with at least 1 year of resistance training experience predicting their proximity to MF in two different experiments using (...) a deception design. Within each experiment participants performed four trials of knee extensions with single sets to their self-determined repetition maximum and MF. For the first experiment participants used loads equal to 70% of a one repetition maximum performed in a separate baseline session. Aiming to minimize participants between day variability in repetition performances, in the second separate experiment they used loads equal to 70% of their daily isometric maximum voluntary contraction. Results suggested that participants typically under predicted the number of repetitions they could perform to MF with a meta-analytic estimate across experiments of 2.0 [95%CIs 0.0 to 4.0]. Participants with at least 1 year of resistance training experience are likely not adequately accurate at gauging effort in submaximal conditions. This suggests that perceptions of effort during resistance training task performance may not be congruent with the actual effort required. This has implications for controlling, programming, and manipulating the actual effort in resistance training and potentially on the magnitude of desired adaptations such as improvements in muscular hypertrophy and strength. (shrink)

Tests of models of reciprocal interactions of testosterone and behaviour patterns in honour subcultures, if based on adult samples measured at a single point in time, would be aided by measures of behaviour in such samples that indirectly index basal testosterone levels at earlier developmental ages, for example, hand preference and other measures of cerebral dominance. Such models raise questions about the social preconditions of honour subcultures, and their indirect effects on health.

Understanding how conceptual structures inform stone tool production and use would help us resolve the issue of a pongid-hominid dichotomy in brain organisation and cognitive ability. Evidence from ideational apraxia suggests that the planning of linguistic and manipulative behaviours is not colocalized in homologous circuits. An alternative account in terms of the evolutionary expansion of the whole prefrontal-premotor area may be more plausible.