Nucleation and growth of crystals at the intermediate stage of phase transformations in binary melts

An exact analytical solution of integro-differential equations, which describe the phase transitions in supercooled binary melts, is constructed with allowance for fluctuating rates of crystal growth. A complete solution of the corresponding Fokker–Planck and balance equations is found for arbitrary nucleation kinetics and growth rates of crystals. In limiting cases, the obtained solutions transform to earlier known solutions for a special form of diffusivity in the space of crystal sizes and purely kinetic and “diffusion-kinetic” growth rates of nuclei.     

Revisiting the Gain–Loss Separability Assumption in Prospect Theory

A fundamental assumption of prospect theory is gain–loss separability (GLS)—the assertion that the overall utility of a prospect can be expressed as a function of the utilities of its positive and negative components. Violations of GLS may potentially limit the generalization of results from studies of single‐domain prospects to mixed prospects and systematically distort the predictions of the theory. Violations also have implications for how choices with positive and negative components should be presented to decision makers. Previous studies, using different elicitation methods, have documented different rates, and types, of systematic violations of GLS. We discuss the differences between two specific elicitation methods—binary choice and certainty equivalents—and report results of a new study of GLS using both methods and randomly generated prospects. We compare the extent and nature of GLS violations under the two elicitation methods using between‐subject and within‐subject analyses. We find (i) systematic violations of GLS under both methods, (ii) higher rates of violations under choice, (iii) higher sensitivity to the outcomes for the certainty equivalents, which is consistent with the predictions of the scale‐compatibility hypothesis, and (iv) different patterns of violations under the two methods, which are explained by method‐specific preferences. We discuss the psychological mechanisms underlying the findings and the implications for presenting information with gain and loss components. Copyright © 2012 John Wiley & Sons, Ltd.     

Structural heterogeneity in a binary Pd–Si metallic glass

A Pd₈₁Si₁₉ bulk metallic glassy rod with a diameter of 4.5 mm was produced by water quenching the fluxed alloy. Despite a negative heat of mixing between Pd and Si elements and very simple components constituting the binary Pd–Si glass-forming system, structural heterogeneity was induced either by slow cooling of a liquid or sub-T_g annealing of glassy ribbons. The sub-T_g annealing experiments evidenced that a more ordered amorphous phase emerged from the original glassy matrix. Our work provides an alternative way to tune the microstructure of metallic glasses by subsequent thermal treatment on an as-prepared single glassy phase.     

Subliminal primes for global or local processing influence judgments of vehicular traffic

Previous studies on semantic priming show that briefly presented words can unconsciously manipulate subjects’ mental states, behaviors, and attitudes. Here we evaluated whether semantic primes can also manipulate the breadth of subjects’ visual attention. We primed participants with briefly presented words that indicate either broadness or narrowness; each prime was followed by either a large or a small picture of a street intersection with vehicles, and participants had to indicate in which order the vehicles were legally allowed to pass the intersection. Participants responded to large pictures faster when primed with words denoting broadness, and to small pictures faster when primed with words denoting narrowness. From this we concluded that semantic priming can be effectively applied to manipulate the breadth of attention, which could be exploited in real-world scenarios.     

Uniform Test Assembly

In educational practice, a test assembly problem is formulated as a system of inequalities induced by test specifications. Each solution to the system is a test, represented by a 0–1 vector, where each element corresponds to an item included (1) or not included (0) into the test. Therefore, the size of a 0–1 vector equals the number of items n in a given item pool. All solutions form a feasible set—a subset of 2 ⁿ vertices of the unit cube in an n-dimensional vector space. Test assembly is uniform if each test from the feasible set has an equal probability of being assembled. This paper demonstrates several important applications of uniform test assembly for educational practice. Based on Slepian’s inequality, a binary program was analytically studied as a candidate for uniform test assembly. The results of this study establish a connection between combinatorial optimization and probability inequalities. They identify combinatorial properties of the feasible set that control the uniformity of the binary programming test assembly. Computer experiments illustrating the concepts of this paper are presented.     

影响驾驶安全的驾驶员危险知觉研究述评

危险知觉是指驾驶员对交通情境中的潜在危险进行识别并做出反应的一种能力。目前,驾驶员危险知觉测量主要使用反应时、眼动或主观评定三种测量方法。在测量中,这三种方法各有优缺点,并出现相互结合的研究趋势。为了提高我国交通安全性,结合国外在提高驾驶员危险预期能力和改善视觉搜索模式两个方面的应用研究,未来国内研究可以在探索危险知觉的认知加工特点、影响因素及加快测量技术的商品化应用等方面加以深入。     

Is Justice Binary?: A Free‐Will‐Related Exploration

Abstract: This article asks whether justice is binary, whether matters are either‐or with respect to it. This question has been inexplicably neglected, and the elementary conceptual work has not been done. We consider this question through exploring the implications of free‐will‐related justice. We see that there are actually two questions of very different scope here, and that two distinct notions of binarity need to be distinguished. In the process, the plausibility of considering justice as a binary notion is evaluated.     

Upper limb movement analysis during gait in multiple sclerosis patients

PurposeGait disorders in multiple sclerosis (MS) are well studied; however, no previous study has described upper limb movements during gait. However, upper limb movements have an important role during locomotion and can be altered in MS patients due to direct MS lesions or mechanisms of compensation. The aim of this study was to describe the arm movements during gait in a population of MS patients with low disability compared with a healthy control group.MethodsIn this observational study we analyzed the arm movements during gait in 52 outpatients (mean age: 39.7 ± 9.6 years, female: 40%) with relapsing-remitting MS with low disability (mean EDSS: 2 ± 1) and 25 healthy age-matched controls using a 3-dimension gait analysis.ResultsMS patients walked slower, with increased mean elbow flexion and decreased amplitude of elbow flexion (ROM) compared to the control group, whereas shoulder and hand movements were similar to controls. These differences were not explained by age or disability.ConclusionUpper limb alterations in movement during gait in MS patients with low disability can be characterized by an increase in mean elbow flexion and a decrease in amplitude (ROM) for elbow flexion/extension. This upper limb movement pattern should be considered as a new component of gait disorders in MS and may reflect subtle motor deficits or the use of compensatory mechanisms.     

Multivariate pattern analysis of event-related potentials predicts the subjective relevance of everyday objects

Potentially decision-relevant stimuli have been proposed to undergo immediate semantic processing. The current study investigated whether information regarding the general desirability (‘Wanting’) of visually presented ‘everyday’ objects was rapidly and automatically processed. Participants completed a foreground task while their electroencephalogram (EEG) was recorded, and task-irrelevant images were presented in the background. Following this, participants rated the images with regards to Wanting and the potentially related attributes of Relevance, Familiarity, Aesthetic Pleasantness and Time Reference. Multivariate pattern classification was used to predict the ratings from patterns of EEG data. Prediction of Wanting and Relevance was possible between 100 and 150 ms following stimulus presentation. The other dimensions could not be predicted. Wanting and Relevance ratings were highly correlated and displayed similar feature weight maps. The current results suggest that the general desirability and subjective relevance of everyday objects is rapidly and automatically processed for a wide range of visual stimuli.