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Music-reading expertise modulates the visual span for English letters but not Chinese characters.
Recent research has suggested that the visual span in stimulus identification can be enlarged through perceptual learning. Since both English and music reading involve left-to-right sequential symbol processing, music-reading experience may enhance symbol identification through perceptual learning particularly in the right visual field (RVF). In contrast, as Chinese can be read in all directions, and components of Chinese characters do not consistently form a left-right structure, this hypothesized RVF enhancement effect may be limited in Chinese character identification. To test these hypotheses, here we recruited musicians and nonmusicians who read Chinese as their first language (L1) and English as their second language (L2) to identify music notes, English letters, Chinese characters, and novel symbols (Tibetan letters) presented at different eccentricities and visual field locations on the screen while maintaining central fixation. We found that in English letter identification, significantly more musicians achieved above-chance performance in the center-RVF locations than nonmusicians. This effect was not observed in Chinese character or novel symbol identification. We also found that in music note identification, musicians outperformed nonmusicians in accuracy in the center-RVF condition, consistent with the RVF enhancement effect in the visual span observed in English-letter identification. These results suggest that the modulation of music-reading experience on the visual span for stimulus identification depends on the similarities in the perceptual processes involved
Regulation effects of exogenous gibberellin acid (GA3) on the formation of tomato (Solanum Lycoperscium) ovary locule and fasciated transcription
To fully understand the regulation effects of gibberellin on tomato (Solanum Lycoperscium) ovary locule formation and the fasciated transcription, two varieties: multi-locule âMLK1â and few- locule âFL1â which were highly different in locule number and fasciated transcriptional levels, were used in this study. By spraying GA3 and PAC (paclobutrazol; an inhibitor of gibberellin biosynthesis) with different concentrations, we found that GA3 increased the locule number, especially, in âMLK1â. At the same time, we chose the suitable treatment concentrations of GA3 and PAC (GA3, 80 mg·L-1, PAC, 80 mg·L-1) which were applied on the âMLK1â and âFL1â to analyze the fasciated transcriptional levels and we found that GA3 repressed the fasciated transcriptional level while PAC increased it. The results implied that the GA3 regulated the ovary locule formation through controlling the fasciated transcription levels.Keywords: Tomato, fasciated, GA3, locule numbe
An n-sided polygonal model to calculate the impact of cyber security events
This paper presents a model to represent graphically the impact of cyber
events (e.g., attacks, countermeasures) in a polygonal systems of n-sides. The
approach considers information about all entities composing an information
system (e.g., users, IP addresses, communication protocols, physical and
logical resources, etc.). Every axis is composed of entities that contribute to
the execution of the security event. Each entity has an associated weighting
factor that measures its contribution using a multi-criteria methodology named
CARVER. The graphical representation of cyber events is depicted as straight
lines (one dimension) or polygons (two or more dimensions). Geometrical
operations are used to compute the size (i.e, length, perimeter, surface area)
and thus the impact of each event. As a result, it is possible to identify and
compare the magnitude of cyber events. A case study with multiple security
events is presented as an illustration on how the model is built and computed.Comment: 16 pages, 5 figures, 2 tables, 11th International Conference on Risks
and Security of Internet and Systems, (CRiSIS 2016), Roscoff, France,
September 201
Gaussian Process Surrogate Models for Neural Networks
Not being able to understand and predict the behavior of deep learning systems makes it hard to decide what architecture and algorithm to use for a given problem. In science and engineering, modeling is a methodology used to understand complex systems whose internal processes are opaque. Modeling replaces a complex system with a simpler, more interpretable surrogate. Drawing inspiration from this, we construct a class of surrogate models for neural networks using Gaussian processes. Rather than deriving kernels for infinite neural networks, we learn kernels empirically from the naturalistic behavior of finite neural networks. We demonstrate our approach captures existing phenomena related to the spectral bias of neural networks, and then show that our surrogate models can be used to solve practical problems such as identifying which points most influence the behavior of specific neural networks and predicting which architectures and algorithms will generalize well for specific datasets
In Situ Structure Characterization in Slot-Die-Printed All-Polymer Solar Cells with Efficiency Over 9%
Herein, high-performance printed all-polymer solar cells (all-PSCs) based on a bulk-heterojunction (BHJ) blend film are demonstrated using PTzBI as the donor and N2200 as the acceptor. A slot-die process is used to prepare the BHJ blend, which is a cost-effective, high-throughput approach to achieve large-area photovoltaic devices. The real-time crystallization of polymers in the film drying process is investigated by in situ grazing incidence wide-angle X-ray scattering characterization. Printing is found to significantly improve the crystallinity of the polymer blend in comparison with spin coating. Moreover, printing with 1,8-diiodooctane as the solvent additive enhances the polymer aggregation and crystallization during solvent evaporation, eventually leading to multi-length-scale phase separation, with PTzBI-rich domains in-between the N2200 crystalline fibers. This unique morphology achieved by printing fabrication results in an impressively high power conversion efficiency of 9.10%, which is the highest efficiency reported for printed all-PSCs. These findings provide important guidelines for controlling film drying dynamics for processing all-PSCs
The effect of calcium on auxin depletion-induced tomato (Lycopersicon esculentum Mill.) pedicel abscission
Indole-3-acetic acid (IAA) and calcium are the most important factors that instigate plant organ abscission. This study aimed to elucidate the mechanisms that underlie the effects of IAA and calcium on delayed abscission in tomato. The results showed a clear trend towards reduced abscission rates with increased concentrations of IAA, and the applications on pedicel proximal or distal side also resulted in a different abscission. IAA combined with calcium significantly improved inhibition in contrast to IAA only, while IAA combined with magnesium exhibited little increased inhibition. 1-NNaphthylphthalamic acid (NPA), a polar auxin transport inhibitor, accelerated the abscission. IAA transported basipetally through an assay with 4 mm long pedicel sections indicated that the average transport intensity of [3H]-IAA applied to the distal pedicel end was 65 Bq hâ1 and the average velocity was 5.29 mm h-1. When the proximal side was incubated in [3H]-IAA, its average transport intensity reduced to 19.53 Bq hâ1 and the average velocity was only 1.92 mm h-1. Calcium treatment enhanced IAA transportation, as shown by significantly enhancing the transport intensity, but it had no effect on velocity.Keywords: Indole-3-acetic acid (IAA), calcium, abscission, tomat
Computational algebraic methods in efficient estimation
A strong link between information geometry and algebraic statistics is made
by investigating statistical manifolds which are algebraic varieties. In
particular it it shown how first and second order efficient estimators can be
constructed, such as bias corrected Maximum Likelihood and more general
estimators, and for which the estimating equations are purely algebraic. In
addition it is shown how Gr\"obner basis technology, which is at the heart of
algebraic statistics, can be used to reduce the degrees of the terms in the
estimating equations. This points the way to the feasible use, to find the
estimators, of special methods for solving polynomial equations, such as
homotopy continuation methods. Simple examples are given showing both equations
and computations. *** The proof of Theorem 2 was corrected by the latest
version. Some minor errors were also corrected.Comment: 21 pages, 5 figure
Implicit Mann approximation with perturbations for nonexpansive semigroups in CAT(0) spaces
Author name used in this publication: Tsz-leung Yip2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Multiscale correlative tomography: an investigation of creep cavitation in 316 stainless steel
Creep cavitation in an ex-service nuclear steam header Type 316 stainless steel sample is investigated through a multiscale tomography workflow spanning eight orders of magnitude, combining X-ray computed tomography (CT), plasma focused ion beam (FIB) scanning electron microscope (SEM) imaging and scanning transmission electron microscope (STEM) tomography. Guided by microscale X-ray CT, nanoscale X-ray CT is used to investigate the size and morphology of cavities at a triple point of grain boundaries. In order to understand the factors affecting the extent of cavitation, the orientation and crystallographic misorientation of each boundary is characterised using electron backscatter diffraction (EBSD). Additionally, in order to better understand boundary phase growth, the chemistry of a single boundary and its associated secondary phase precipitates is probed through STEM energy dispersive X-ray (EDX) tomography. The difference in cavitation of the three grain boundaries investigated suggests that the orientation of grain boundaries with respect to the direction of principal stress is important in the promotion of cavity formation
Growth and dislocation studies of ÎČ-HMX
Background: The defect structure of organic materials is important as it plays a major role in their crystal growth
properties. It also can play a subcritical role in âhot-spotâ detonation processes of energetics and one such
energetic is cyclotetramethylene-tetranitramine, in the commonly used beta form (ÎČ-HMX).
Results: The as-grown crystals grown by evaporation from acetone show prismatic, tabular and columnar habits, all
with {011}, {110}, (010) and (101) faces. Etching on (010) surfaces revealed three different types of etch pits, two of
which could be identified with either pure screw or pure edge dislocations, the third is shown to be an artifact of
the twinning process that this material undergoes. Examination of the {011} and {110} surfaces show only one type
of etch pit on each surface; however their natural asymmetry precludes the easy identification of their Burgers
vector or dislocation type. Etching of cleaved {011} surfaces demonstrates that the etch pits can be associated with
line dislocations. All dislocations appear randomly on the crystal surfaces and do not form alignments characteristic
of mechanical deformation by dislocation slip.
Conclusions: Crystals of ÎČ-HMX grown from acetone show good morphological agreement with that predicted by
modelling, with three distinct crystal habits observed depending upon the supersaturation of the growth solution.
Prismatic habit was favoured at low supersaturation, while tabular and columnar crystals were predominant at
higher super saturations. The twin plane in ÎČ-HMX was identified as a (101) reflection plane. The low plasticity of
ÎČ-HMX is shown by the lack of etch pit alignments corresponding to mechanically induced dislocation arrays.
On untwinned {010} faces, two types of dislocations exist, pure edge dislocations with b = [010] and pure screw
dislocations with b = [010]. On twinned (010) faces, a third dislocation type exists and it is proposed that these pits
are associated with pure screw dislocations with b = [010]
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