A collective scattering system for measuring electron gyroscale fluctuations on the National Spherical Torus Experiment

A collective scattering system has been installed on the National Spherical Torus Experiment (NSTX) to measure electron gyroscale fluctuations in NSTX plasmas. The system measures fluctuations with k(perpendicular to)rho(e)less than or similar to 0.6 and k(perpendicular to)less than or similar to 20 cm(-1). Up to five distinct wavenumbers are measured simultaneously, and the large toroidal curvature of NSTX plasmas provides enhanced spatial localization. Steerable optics can position the scattering volume throughout the plasma from the magnetic axis to the outboard edge. Initial measurements indicate rich turbulent dynamics on the electron gyroscale. The system will be a valuable tool for investigating the connection between electron temperature gradient turbulence and electron thermal transport in NSTX plasmas.X1137sciescopu

Leitfaden Saatgutgesundheit im Ökologischen Landbau - Ackerkulturen

Im "Leitfaden Saatgutgesundheit im Ökologischen Landbau – Ackerkulturen" werden ausgewählte saatgutbürtige Krankheiten von ackerbaulichen Kulturen samt vorbeugenden und direkten Regulierungsmöglichkeiten vorgestellt

Exploring the Effects of Non-traditional Narrative Video Ads on Tourism Intentions Among Viewers with and without Previous Destination Experience.

Tourism is a storying and narrative experience that weaves multiple accounts about travel destinations, sites, and people into consumer expectations and perceptions of what is authentic in a travel experience (Chronis 2012a, Moscardo 2010, Bruner 2005). Story-telling narratives use the natural link of human experience often shared with others (Zhong et al. 2017, Mossberg 2008, McCabe and Foster 2006) and have become a helpful communication tool for understanding and promoting tourism (Zhong, Yun, Busser, and Baloglu 2017). Story-telling narration provides a valuable framework in which the destination is portrayed as believable and authentic to potential tourists (Kim and Yuon 2017). Our research has two main objectives: 1.) to explore the influence of narrative video advertisements on perceptions of authenticity, and 2.) to determine the role of individual differences and their effects on perceptions of authenticity. Our study\u27s two ads were specifically designed to feature attributes not commonly part of the City\u27s authentic historical appeal. As such, the focus of the ads could be perceived as less authentic by the viewer. We examine the role of narrative story-telling in shaping positive perceptions of authenticity for advertisements that explore non-traditional tourism appeals. We further explore how the viewer\u27s prior visits to the Cityinfluence perceptions of authenticity and subsequent ad effectiveness. The promotion of non-historic features was designed to influence repeat visits with something new to experience and potential visitors who might be more interested in non-historic experiences. Previous visitors might not be open to stories related to activities that were not necessarily related to their previous visits and find the ad less authentic but still respond to new experiences\u27 potential

Perceived Masculinity/Femininity of Managers and the Feedback Environment

Past research suggests that the masculinity/femininity of a supervisor plays a role in the effectiveness of his/her leadership in organizations. This study looked into the relationship between the perceived masculinity and femininity of supervisors by employees and the feedback environment. The data for the research were collected from 66 men and 78 women in the United States who were working 20 or more hours per week using Amazon’s Mechanical Turk website. The survey was the combination of the supervisor subscale of the Feedback Environment Scale (FES) and a slightly modified version of the Personal Attributes Questionnaire (PAQ). Each of the seven dimensions of the Feedback Environment Scale were correlated with the ratings on the Personal Attributes Questionnaire. The results identified a relationship between the perceived masculinity and femininity of supervisors and the feedback environment. It was also discovered that femininity significantly correlated more with the feedback environment than masculinity

Islands of conformational stability for Filopodia

Filopodia are long, thin protrusions formed when bundles of fibers grow outwardly from a cell surface while remaining closed in a membrane tube. We study the subtle issue of the mechanical stability of such filopodia and how this depends on the deformation of the membrane that arises when the fiber bundle adopts a helical configuration. We calculate the ground state conformation of such filopodia, taking into account the steric interaction between the membrane and the enclosed semiflexible fiber bundle. For typical filopodia we find that a minimum number of fibers is required for filopodium stability. Our calculation elucidates how experimentally observed filopodia can obviate the classical Euler buckling condition and remain stable up to several tens of . We briefly discuss how experimental observation of the results obtained in this work for the helical-like deformations of enclosing membrane tubes in filopodia could possibly be observed in the acrosomal reactions of the sea cucumber Thyone, and the horseshoe crab Limulus. Any realistic future theories for filopodium stability are likely to rely on an accurate treatment of such steric effects, as analysed in this work

Electron gyroscale fluctuation measurements in National Spherical Torus Experiment H-mode plasmas

A collective scattering system has measured electron gyroscale fluctuations in National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 40, 557 (2000)] H-mode plasmas to investigate electron temperature gradient (ETG) turbulence. Observations and results pertaining to fluctuation measurements in ETG-stable regimes, the toroidal field scaling of fluctuation amplitudes, the relation between fluctuation amplitudes and transport quantities, and fluctuation magnitudes and k-spectra are presented. Collectively, the measurements provide insight and guidance for understanding ETG turbulence and anomalous electron thermal transport. (C) 2009 American Institute of Physics. [doi:10.1063/1.3262530]X116sciescopu

Short-scale turbulent fluctuations driven by the electron-temperature gradient in the national spherical torus experiment

Measurements with coherent scattering of electromagnetic waves in plasmas of the National Spherical Torus Experiment indicate the existence of turbulent fluctuations in the range of wave numbers k(perpendicular to)rho(e)=0.1-0.4, corresponding to a turbulence scale length nearly equal to the collisionless skin depth. Experimental observations and agreement with numerical results from a linear gyrokinetic stability code support the conjecture that the observed turbulence is driven by the electron-temperature gradient.X1155sciescopu

Observations of Reduced Electron Gyroscale Fluctuations in National Spherical Torus Experiment H-Mode Plasmas with Large E X B Flow Shear

Electron gyroscale fluctuation measurements in National Spherical Torus Experiment H-mode plasmas with large toroidal rotation reveal fluctuations consistent with electron temperature gradient (ETG) turbulence. Large toroidal rotation in National Spherical Torus Experiment plasmas with neutral beam injection generates ExB flow shear rates comparable to ETG linear growth rates. Enhanced fluctuations occur when the electron temperature gradient is marginally stable with respect to the ETG linear critical gradient. Fluctuation amplitudes decrease when the ExB flow shear rate exceeds ETG linear growth rates. The observations indicate that ExB flow shear can be an effective suppression mechanism for ETG turbulence.X1129sciescopu

Improved Algorithms for Approximate String Matching (Extended Abstract)

The problem of approximate string matching is important in many different areas such as computational biology, text processing and pattern recognition. A great effort has been made to design efficient algorithms addressing several variants of the problem, including comparison of two strings, approximate pattern identification in a string or calculation of the longest common subsequence that two strings share. We designed an output sensitive algorithm solving the edit distance problem between two strings of lengths n and m respectively in time O((s-|n-m|)min(m,n,s)+m+n) and linear space, where s is the edit distance between the two strings. This worst-case time bound sets the quadratic factor of the algorithm independent of the longest string length and improves existing theoretical bounds for this problem. The implementation of our algorithm excels also in practice, especially in cases where the two strings compared differ significantly in length. Source code of our algorithm is available at http://www.cs.miami.edu/\~dimitris/edit_distanceComment: 10 page