Limb apparent motion perception: modification by tDCS, and clinically or experimentally altered bodily states

Limb apparent motion perception (LAMP) refers to the illusory visual perception of a moving limb upon observing two rapidly alternating photographs depicting the same limb in two different postures. Fast stimulus onset asynchronies (SOAs) induce the more visually guided perception of physically impossible movements. Slow SOAs induce the perception of physically possible movements. According to the motor theory of LAMP, the latter perception depends upon the observers’ sensorimotor representations. Here, we tested this theory in two independent studies by performing a central (study 1) and peripheral (study 2) manipulation of the body’s sensorimotor states during two LAMP tasks. In the first sham-controlled transcranial direct current stimulation between-subject designed study, we observed that the dampening of left sensorimotor cortex activity through cathodal stimulation biased LAMP towards the more visually guided perception of physically impossible movements for stimulus pairs at slow SOAs. In the second, online within-subject designed study, we tested three participant groups twice: (1) individuals with an acquired lower limb amputation, either while wearing or not wearing their prosthesis; (2) individuals with body integrity dysphoria (i.e., with a desire for amputation of a healthy leg) while sitting in a regular position or binding up the undesired leg (to simulate the desired amputation); (3) able-bodied individuals while sitting in a normal position or sitting on one of their legs. We found that the momentary sensorimotor state crucially impacted LAMP in all groups. Taken together, the results of these two studies substantiate the motor theory of LAMP.

Increase of efficiency of actuators of spacecraft thermal control system in outer space

The article deals with the methods of transfer of thermal energy of electric heaters to the nodes and devices of non-pressurized spacecraft, which are part of the spacecraft in the target orbits in the conditions of regular use. The basic technical characteristics of perspective electric heaters for operating conditions are developed, the model of regular position of electric heaters allowing to define ways of increase of efficiency and efficiency of electric heaters is developed. The main results of the development of flexible film electric heaters various design using materials produced by the domestic industry and manufactured using a new method based on the method of photolithography and etching the resistive layer, allowing to implement new functionality and improve efficiency of electric heaters, the experiments confirming the calculations in conditions simulating operational influences on electric heaters. The using of flexible film electric heaters increased efficiency in the existing and future spacecraft can improve the efficiency of the thermal control system as a whole, improves manufacturability.

De plaats van het voorzetselvoorwerp

This paper presents the results of a corpus study of Dutch complement PPs. On the basis of a collection of 3400 occurrences in negative sentences, the four major word order patterns (regular position, scrambling order, topicalization and extraposition) are studied, both in main and subordinate clauses, and linked to the properties of the prepositional phrases, in particular weight and definiteness. Greater weight corresponds to higher likelihood of extraposition, and definiteness to higher likelihood of scrambling and topicalization. This corresponds well with earlier studies of word order variation in Dutch, but had not been established for the class of complement PPs. Among definite phrases, PPs with so-called R-pronouns, such as hieraan ‘here-on’ and daarvan ‘thereof’ showed especially high preferences for topicalization and scrambling. Negative sentences were selected for this study to avoid cases where regular order and scrambling order could not be distinguished due to lack of adverbial elements in the middle field. The data set is temporally stratified. This made it possible to study changes over time, and the most robust finding was a continuous retreat of the scrambling order throughout the period 1700-2014.

REWRITING SYSTEMS IN ALTERNATING KNOT GROUPS

Every tame, prime and alternating knot is equivalent to a tame, prime and alternating knot in regular position, with a common projection. In this work, we show that the augmented Dehn presentation of the knot group of a tame, prime, alternating knot in regular position, with a common projection has a finite and complete rewriting system. This provides an algorithm for solving the word problem with this presentation and we find an algorithm for solving the word problem with the Dehn presentation also.

First Principles Calculation of Cooperative Atom Migration in L12 Ni3Al

ABSTRACTRecent Monte-Carlo simulations of order relaxations in L12-ordered Ni3Al reproduced the simultaneous action of two processes as experimentally observed by residual resistometry. It was shown that the fast process is related to the fast annihilation/creation of nearest neighbour antisite pairs. These findings are now strongly corroborated by a new supercell approach of ab initio quantum mechanical calculations describing the simultaneous displacement of Ni and Al atoms on their way to their respective antisite positions. Studies of single jumps suggest that such a cooperative migration of Ni and Al is necessary in order to prevent Al antisites from jumping back into their regular position. Relaxation of neighbouring atoms was taken into account. Thus, a minimum migration barrier of about 3 eV was derived which together with the calculated formation enthalpy of a Ni vacancy of 1.5 eV amounts to 4.5 eV, in remarkable agreement with the high activation enthalpy of 4.6 eV as observed experimentally.

What Are the Functional Orthographic Units in Chinese Word Recognition: The Stroke or the Stroke Pattern?

We present evidence that the visual analysis of Chinese characters by skilled readers is based upon well-defined orthographic constituents. These functional units are the recurrent, integral stroke-patterns, not the individual strokes as previously thought. The speed of simultaneous “same-different” comparisons of Chinese characters is affected by the number of these orthographic units and, for “different” judgements, by the proportion of mismatching units, but not by the number of individual strokes. We further define a category of orthographic unit, referred to here as the “lexical radical”, which requires strict positional regularity within each composite character. Violation of positional regularity results in illegal non-characters. In contrast, recombination of orthographic units (stroke patterns) with the lexical radical in its regular position forms a regular pseudocharacter. We show that real characters are matched faster than pseudocharacters and non-characters—a word superiority effect in Chinese. Pseudocharacters are matched faster than non-characters, a pseudoword advantage in Chinese. We also present evidence suggesting that individual stroke patterns may be better recognized in real characters than in pseudocharacters and non-characters—a word superiority effect in terms of unit recognition. These results support the hypothesis that the functional orthographic unit in the recognition of Chinese characters, comparable to the letter in alphabetic word recognition, is the recurring integral stroke pattern.