Joseph Baker & Nick Wattie – new insights into the concept of innate talent in sport

In this target article, Joseph Baker and Nick Wattie revisited the review article on the evidence for innate talent published by Howe, Davidson and Sloboda 20 years ago, and focused mainly on whether this concept was reasonable and scientifically sound, and whether the concept of innate talent was valid also in the world of sport. The main article (CISS_3:006) is then discussed by five peer commentaries (CISS_4:102 – CISS_4:106), written by research experts in this field. Finally, Joseph Baker and Nick Wattie provided a closing response (CISS_4:108) acknowledging critiques, suggestions, and extensions brought forward by the commentators

Heterogeneous volatility cascade in financial markets

Using high frequency data, we have studied empirically the change of volatility, also called volatility derivative, for various time horizons. In particular, the correlation between the volatility derivative and the volatility realized in the next time period is a measure of the response function of the market participants. This correlation shows explicitly the heterogeneous structure of the market according to the characteristic time horizons of the differents agents. It reveals a volatility cascade from long to short time horizons, with a structure different from the one observed in turbulence. Moreover, we have developed a new ARCH-type model which incorporates the different groups of agents, with their characteristic memory. This model reproduces well the empirical response function, and allows us to quantify the importance of each group.Comment: 10 pages, 2 figures, To be published in Physica

What Dyadic Reparation Is Meant to Do: An Association with Infant Cortisol Reactivity

BACKGROUND The latency to reparation of interactive mismatches (interactive repair) is argued to regulate infant distress on a psychobiological level, and maternal anxiety disorders might impair infant regulation. SAMPLING AND METHODS A total of 46 dyads (19 mothers with an anxiety disorder, 27 controls) were analyzed for associations between interactive repair and infant cortisol reactivity during the Face-to-Face-Still-Face paradigm 3-4 months postpartum. Missing cortisol values (n = 16) were imputed. Analyses were conducted on both the original and the pooled imputed data. RESULTS Interactive repair during the reunion episode was associated with infant cortisol reactivity (original data: p 0.23). Additional stepwise regression analyses found that latency to repair during play (p < 0.01), an interaction between distress during the first trimester of pregnancy and latency to repair during reunion (p < 0.01) and infant self-comforting behaviors during the reunion episode (p = 0.04) made independent contributions to cortisol reactivity in the final regression model. CONCLUSIONS This is the first study demonstrating that interactive repair is related to infant psychobiological stress reactivity. The lack of a relation to maternal anxiety disorder may be due to the small sample size. However, this result emphasizes that infants respond to what they experience and not to the maternal diagnostic category

Superconducting Accelerating Cavity Pressure Sensitivity Analysis and Stiffening

The Soreq Applied Research Accelerator Facility (SARAF) design is based on a 40 MeV 5 mA light ions superconducting RF linac. Phase-I of SARAF delivers up to 2 mA CW proton beams in an energy range of 1.5 - 4.0 MeV. The maximum beam power that we have reached is 5.7 kW. Today, the main limiting factor to reach higher ion energy and beam power is related to the HWR sensitivity to the liquid helium coolant pressure fluctuations. The HWR sensitivity to helium pressure is about 60 Hz/mbar. The cavities had been designed, a decade ago, to be soft in order to enable tuning of their novel shape. However, the cavities turned out to be too soft. In this work we found that increasing the rigidity of the cavities in the vicinity of the external drift tubes may reduce the cavity sensitivity by a factor of three. A preliminary design to increase the cavity rigidity is presented

Effects of Maternal Anxiety Disorders on Infant Self-Comforting Behaviors: The Role of Maternal Bonding, Infant Gender and Age

Background/Aims: We investigated the links between maternal bonding, maternal anxiety disorders, and infant self comforting behaviors. Furthermore, we looked at the moderating roles of infant gender and age. Methods: Our sample (n = 69) comprised 28 mothers with an anxiety disorder (according to DSM-IV criteria) and 41 controls, each with their 2.5- to 8-month-old infant (41 females and 28 males). Infant behaviors were recorded during the Face-to-Face Still-Face paradigm. Maternal bonding was assessed by the Postpartum Bonding Questionnaire. Results: Conditional process analyses revealed that lower maternal bonding partially mediated between maternal anxiety disorders and increased self-comforting behaviors but only in older female infants (over 5.5 months of age). However, considering maternal anxiety disorders without the influence of bonding, older female infants (over 5.5 months of age) showed decreased rates of self-comforting behaviors, while younger male infants (under 3 months of age) showed increased rates in the case of maternal anxiety disorder. Conclusions: The results suggest that older female infants (over 5.5 months of age) are more sensitive to lower maternal bonding in the context of maternal anxiety disorders. Furthermore, results suggest a different use of self-directed regulation strategies for male and female infants of mothers with anxiety disorders and low bonding, depending on infant age. The results are discussed in the light of gender-specific developmental trajectories. (C) 2016 S. Karger AG, Basel

Partner orbits and action differences on compact factors of the hyperbolic plane. Part I: Sieber-Richter pairs

Physicists have argued that periodic orbit bunching leads to universal spectral fluctuations for chaotic quantum systems. To establish a more detailed mathematical understanding of this fact, it is first necessary to look more closely at the classical side of the problem and determine orbit pairs consisting of orbits which have similar actions. In this paper we specialize to the geodesic flow on compact factors of the hyperbolic plane as a classical chaotic system. We prove the existence of a periodic partner orbit for a given periodic orbit which has a small-angle self-crossing in configuration space which is a `2-encounter'; such configurations are called `Sieber-Richter pairs' in the physics literature. Furthermore, we derive an estimate for the action difference of the partners. In the second part of this paper [13], an inductive argument is provided to deal with higher-order encounters.Comment: to appear on Nonlinearit

Monte Carlo investigations of phase transitions: status and perspectives

Using the concept of finite-size scaling, Monte Carlo calculations of various models have become a very useful tool for the study of critical phenomena, with the system linear dimension as a variable. As an example, several recent studies of Ising models are discussed, as well as the extension to models of polymer mixtures and solutions. It is shown that using appropriate cluster algorithms, even the scaling functions describing the crossover from the Ising universality class to the mean-field behavior with increasing interaction range can be described. Additionally, the issue of finite-size scaling in Ising models above the marginal dimension (d*=4) is discussed.Comment: 23 pages, including 14 PostScript figures. Presented at StatPhys-Taiwan, August 9-16, 1999. Also available as PDF file at http://www.cond-mat.physik.uni-mainz.de/~luijten/erikpubs.htm