Progress in electromechanically active polymers: selected papers from EuroEAP 2017:Editorial

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Cognitive Abilities in the Wild: Population-scale game-based cognitive assessment

Psychology and the social sciences are undergoing a revolution: It has become increasingly clear that traditional lab-based experiments fail to capture the full range of differences in cognitive abilities and behaviours across the general population. Some progress has been made toward devising measures that can be applied at scale across individuals and populations. What has been missing is a broad battery of validated tasks that can be easily deployed, used across different age ranges and social backgrounds, and employed in practical, clinical, and research contexts. Here, we present Skill Lab, a game-based approach allowing the efficient assessment of a suite of cognitive abilities. Skill Lab has been validated outside the lab in a crowdsourced population-size sample recruited in collaboration with the Danish Broadcast Company (Danmarks Radio, DR). Our game-based measures are five times faster to complete than the equivalent traditional measures and replicate previous findings on the decline of cognitive abilities with age in a large population sample. Furthermore, by combining the game data with an in-game survey, we demonstrate that this unique dataset has implication for key questions in social science, challenging the Jack-of-all-Trades theory of entrepreneurship and provide evidence for risk preference being independent of executive functioning.Comment: 11 pages, 4 figures, and 2 table

The pharmacokinetics of the interstitial space in humans

BACKGROUND: The pharmacokinetics of extracellular solutes is determined by the blood-tissue exchange kinetics and the volume of distribution in the interstitial space in the different organs. This information can be used to develop a general physiologically based pharmacokinetic (PBPK) model applicable to most extracellular solutes. METHODS: The human pharmacokinetic literature was surveyed to tabulate the steady state and equilibrium volume of distribution of the solutes mannitol, EDTA, morphine-6-glucuronide, morphine-3-glucuronide, inulin and β-lactam antibiotics with a range of protein binding (amoxicillin, piperacillin, cefatrizine, ceforanide, flucloxacillin, dicloxacillin). A PBPK data set was developed for extracellular solutes based on the literature for interstitial organ volumes. The program PKQuest was used to generate the PBPK model predictions. The pharmacokinetics of the protein (albumin) bound β-lactam antibiotics were characterized by two parameters: 1) the free fraction of the solute in plasma; 2) the interstitial albumin concentration. A new approach to estimating the capillary permeability is described, based on the pharmacokinetics of the highly protein bound antibiotics. RESULTS: About 42% of the total body water is extracellular. There is a large variation in the organ distribution of this water – varying from about 13% of total tissue water for skeletal muscle, up to 70% for skin and connective tissue. The weakly bound antibiotics have flow limited capillary-tissue exchange kinetics. The highly protein bound antibiotics have a significant capillary permeability limitation. The experimental pharmacokinetics of the 11 solutes is well described using the new PBPK data set and PKQuest. CONCLUSIONS: Only one adjustable parameter (systemic clearance) is required to completely characterize the PBPK for these extracellular solutes. Knowledge of just this systemic clearance allows one to predict the complete time course of the absolute drug concentrations in the major organs. PKQuest is freely available

The Electrical Breakdown Strength of Pre-stretched Elastomers, with and without Sample Volume Conservation

n practice, the electrical breakdown strength of dielectric electroactive polymers (DEAPs) determines the upper limit for transduction. During DEAP actuation, the thickness of the elastomer decreases, and thus the electrical field increases and the breakdown process is determined by a coupled electro-mechanical failure mechanism. A thorough understanding of the mechanisms behind the electro-mechanical breakdown process is required for developing reliable transducers. In this study, two experimental configurations were used to determine the stretch dependence of the electrical breakdown strength of polydimethylsiloxane (PDMS) elastomers. Breakdown strength was determined for samples with and without volume conservation and was found to depend strongly on the stretch ratio and the thickness of the samples. PDMS elastomers are shown to increase breakdown strength by a factor of ~3 when sample thickness decreases from 120 to 30 μm, while the biaxial pre-stretching (λ = 2) of samples leads similarly to an increase in breakdown strength by a factor of ~2.5

Anti-shock controller design for optical drives

In this paper, a dead-zone non-linear control strategy is developed and implemented in an optical drive (CD-RW) to improve anti-shock performance during playing and recording. An experimental platform has been realized to evaluate the shock resistance of the drives using a real-time interface system. This user-friendly platform not only provides an easy and flexible way for the evaluation of the non-linear controller but also allows a quick implementation and evaluation of new control algorithms for Optical Disc Drives. Experimental investigation on the CDRW drive shows that the dead-zone non-linear controller can improve the anti-shock performance by about 60%

Barley metal ion transport proteins involved in manganese acquisition and homeostasis

Manganese (Mn) toxicity is a major problem for plant growth, often caused by acidic soils leading to an excessive plant availability of Mn2+. However, Mn deficiency is also a major nutritional disorder, commonly observed on slightly alkaline soils, which are favoring oxidation of soluble Mn2+ to the plant unavailable form MnO2. The work reported here was initiated with the aim of identifying and characterizing barley Mn2+ transport proteins. Using yeast as a model system we have identified and characterized barley genes encoding Mn2+ transport proteins. The plasma membrane localized HvIRT1 protein is a broad range metal ion transporter. The HvIRT1 transcript expression was induced under Mn and Fe deficiency and the expression level was correlated with the Mn2+ uptake capacity, suggesting an important role of HvIRT1 in Mn2+ acquisition. Two additional genes encoding Mn2+ transport proteins were identified in a Mn2+ tolerance yeast assay; one belonging to the CDF family designated HvMTP8.1 and one homologous gene to the yeast CCC1, named HvVIT1. It is proposed that HvMTP8.1 has a role in Mn2+ efflux mechanisms into the apoplast whereas HvVIT1 are involved in Mn2+ sequestration into internal cellular compartments. The results presented provide the basis for an improved understanding of the mechanisms involved in Mn2+ acquisition and homeostasis in crop plants. This information will facilitate engineering of genotypes able to grow efficiently on marginal soils