The nature and origin of syntactic recursion in natural languages is a topical problem. Important recent contributions include those of Johansson (2005), Parker (2006), Tomalin (2006; 2007), and Heine and Kuteva (2007). Syntactic recursion will here be discussed especially in relation to its cognate concept of iteration. Their basic common feature is plain structural repetition: “keep on emitti...

Environmental change can simultaneously cause abiotic stress and alter biological communities, yet adaptation of natural populations to co-changing environmental factors is poorly understood. We studied adaptation to acid and predator stress in six moor frog (Rana arvalis) populations along an acidification gradient, where abundance of invertebrate predators increases with increasing acidity of...

Visualization of CFD simulation data on unstructured, 3D grids poses several challenges. The wide range of real-world data set sizes and the geometric versatility within individual, unstructured CFD simulation models present special challenges to the engineers analyzing flow simulation results. Users also face perceptual problems such as occlusion, visual complexity, lack of directional cues, a...

The general theory of nuclear magnetic resonance (NMR) imaging of large electromagnetically active systems is considered. We emphasize particularly noninvasive geophysical applications such as the imaging of subsurface water content. We derive a general formula for the NMR response voltage, valid for arbitrary transmitter and receiver loop geometry and arbitrary conductivity structure of the me...

—Studies of prey responses to different predators are needed to investigate costs and benefits of particular antipredator responses and to unravel community-level effects on phenotypic plasticity. We reared laboratory-bred larvae of Arizona Tiger Salamanders, Ambystoma tigrinum nebulosum with either of two common predators, diving beetle larvae (Dytiscus sp.) or dragonfly naiads (Anax junius). ...