Exponential Divergence and Long Time Relaxation in Chaotic Quantum Dynamics

Phase space representations of the dynamics of the quantal and classical cat map are used to explore quantum--classical correspondence in a K-system: as $\hbar \to 0$, the classical chaotic behavior is shown to emerge smoothly and exactly. The quantum dynamics near the classical limit displays both exponential separation of adjacent distributions and long time relaxation, two characteristic features of classical chaotic motion.Comment: 10 pages, ReVTeX, to appear in Phys. Rev. Lett. 13 figures NOT included. Available either as LARGE (uuencoded gzipped) postscript files or hard-copies from [email protected]

Developmental activities that contribute to creative decision making in skilled soccer players

The ability to produce creative decisions during match-play is a key attribute of team sports players (Memmert & Roca, 2019). Yet, very few researchers have studied how this type of creative behavior is acquired and developed in the sporting domain. The aim of this study was to assess the link between sport-specific creative decision making and prior engagement in developmental activities in skilled adult soccer players. Players were classified as either high- or low-creative decision makers based on their performance on an established soccer-specific video-based creativity test. Their decisions on the test were measured using the three observation criteria for creativity of originality, flexibility, and fluency. We used retrospective recall questionnaires to collect participation history data on their engagement in soccer and other sport development activities. Results showed that the high-creative decision-making group accumulated significantly more hours per year (M = 345 h · year – 1) in free, unstructured soccer-specific play activity during childhood and early adolescence (6-15 years of age) when compared to those classified as low-creative (M = 192 h · year – 1). No differences were reported for hours per year in soccer-specific formal practice or competition between the two groups throughout their development. Moreover, hours accumulated in other sports and milestones achieved did not differentiate groups. Our findings suggest that informal unorganized, free play in the primary sport is positively associated with and necessary for the development of superior levels of creative decision making in this sport

Ethanol triggers grape gene expression leading to anthocyanin accumulation during berry ripening

Recent studies have shown that low doses of ethanol stimulate the maturation of some fruits. The present work showed that spraying Cabernet Sauvignon grapes, with 5% ethanol at veraison enhances the anthocyanin accumulation. Veraison is the time when the berries turn from green to purple. HPLC analysis showed a marked increase in the total concentrations of the derivatives of delphinidin, cyanidin, petunidin, peonidin and malvidin from the fourth day after the ethanol treatment until harvest. This was not linked to a difference in berry weight in comparison to controls. Two distinct expression patterns were found for anthocyanin biosynthesis genes in the treated and untreated berries. For one group, consisting of chalcone synthase, flavanone-3-hydroxylase, dihydroxyflavonol-4-reductase and leucoanthocyanidin dioxygenase, the expression was inhibited or unchanged by the ethanol treatment, whereas for UDP glucose-flavonoid 3-O-glucosyltransferase (UFGT) there was a marked increase in expression from 1 to 20 days after ethanol treatment. These results suggest that the UFGT gene is a key factor in the observed anthocyanin accumulation following ethanol treatment

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Developmental activities that contribute to creativity in soccer players

Introduction: The most skilled soccer players create excitement for spectators when they touch the ball because they often produce unique, creative actions during match-play. The ability to produce creative decisions in game situations is a key attribute of team sports players (Memmert & Roca, 2019). Yet very few researchers have studied how this type of creative behavior is acquired and developed in the sporting domain. The aim of this study was to assess the link between sport-specific creative decision making and prior engagement in developmental activities in skilled adult soccer players. Methods: Players were classified as either high- or low-creative decision makers based on their performance on an established soccer-specific video-based creativity test. Their solutions on the test were measured using the three observation criteria for creativity of originality, flexibility, and fluency of decisions. We used retrospective recall questionnaires to collect participation history data on their engagement in soccer and other sport development activities. Results: The high-creative group spent significantly more average hours per year (M = 345 h · year – 1) in free, unstructured soccer-specific play activity during childhood and early adolescence (i.e., 6-15 years of age) when compared with their low-creative counterparts (M = 192 h · year – 1). No differences were reported for hours per year in soccer-specific formal practice or competition between the two groups throughout their development. Moreover, hours accumulated in other sports, as well as milestones achieved, did not differentiate groups. Conclusion: Our findings suggest that informal unorganized, free play in the primary sport is positively associated with and necessary for the development of superior levels of creative decision making in this sport

A Comparison of Survey Methods for Documenting Presence of Myotis leibii (Eastern Small-Footed Bats) at Roosting Areas in Western Virginia

Many aspects of foraging and roosting habitat of Myotis leibii (Eastern Small-Footed Bat), an emergent rock roosting-obligate, are poorly described. Previous comparisons of effectiveness of acoustic sampling and mist-net captures have not included Eastern Small-Footed Bat. Habitat requirements of this species differ from congeners in the region, and it is unclear whether survey protocols developed for other species are applicable. Using data from three overlapping studies at two sampling sites in western Virginia’s central Appalachian Mountains, detection probabilities were examined for three survey methods (acoustic surveys with automated identification of calls, visual searches of rock crevices, and mist-netting) for use in the development of “best practices” for future surveys and monitoring. Observer effects were investigated using an expanded version of visual search data. Results suggested that acoustic surveys with automated call identification are not effective for documenting presence of Eastern Small-Footed Bats on talus slopes (basal detection rate of 0%) even when the species is known to be present. The broadband, high frequency echolocation calls emitted by Eastern Small-Footed Bat may be prone to attenuation by virtue of their high frequencies, and these factors, along with signal reflection, lower echolocation rates or possible misidentification to other bat species over talus slopes may all have contributed to poor acoustic survey success. Visual searches and mist-netting of emergent rock had basal detection probabilities of 91% and 75%, respectively. Success of visual searches varied among observers, but detection probability improved with practice. Additionally, visual searches were considerably more economical than mist-netting