13 research outputs found
Plastic deformation of polycrystals of Co
The plastic behaviour of Co3(Al, W) polycrystals with the L12 structure has been investigated in compression from 77 to 1273 K. The yield stress exhibits a rapid decrease at low temperatures (up to room temperature) followed by a plateau (up to 950 K), then it increases anomalously with temperature in a narrow temperature range between 950 and 1100 K, followed again by a rapid decrease at high temperatures. Slip is observed to occur exclusively on {111} planes at all temperatures investigated. The rapid decrease in yield stress observed at low temperatures is ascribed to a thermal component of solid-solution hardening that occurs during the motion of APB-coupled dislocations whose core adopts a planar, glissile structure. The anomalous increase in yield stress is consistent with the thermally activated cross-slip of APB-coupled dislocations from (111) to (010), as for many other L12 compounds. Similarities and differences in the deformation behaviour and operating mechanisms among Co3(Al, W) and other L12 compounds, such as Ni3Al and Co3Ti, are discussed
Development of a Serial Order in Speech Constrained by Articulatory Coordination
<div><p>Universal linguistic constraints seem to govern the organization of sound sequences in words. However, our understanding of the origin and development of these constraints is incomplete. One possibility is that the development of neuromuscular control of articulators acts as a constraint for the emergence of sequences in words. Repetitions of the same consonant observed in early infancy and an increase in variation of consonantal sequences over months of age have been interpreted as a consequence of the development of neuromuscular control. Yet, it is not clear how sequential coordination of articulators such as lips, tongue apex and tongue dorsum constrains sequences of labial, coronal and dorsal consonants in words over the course of development. We examined longitudinal development of consonant-vowel-consonant(-vowel) sequences produced by Japanese children between 7 and 60 months of age. The sequences were classified according to places of articulation for corresponding consonants. The analyses of individual and group data show that infants prefer repetitive and fronting articulations, as shown in previous studies. Furthermore, we reveal that serial order of different places of articulations within the same organ appears earlier and then gradually develops, whereas serial order of different articulatory organs appears later and then rapidly develops. In the same way, we also analyzed the sequences produced by English children and obtained similar developmental trends. These results suggest that the development of intra- and inter-articulator coordination constrains the acquisition of serial orders in speech with the complexity that characterizes adult language.</p></div
The developmental changes in serial order in articulation of consonants obtained by the analysis of individual and group data for Japanese.
<p>Middle and right columns show developmental curves obtained by the analysis of individual and group data for Japanese, respectively. Each row indicates (i) repetitions, (ii) fronting, (ii) intra-organ articulations, and (iv) inter-organ articulations. In the middle column, circles, squares and triangles denote relative ratio of each type of CVC patterns produced by child B, child C and child D, respectively. Black, gray and silver curves indicate that developmental curves of child B, child C and child D, respectively. In the right column, circles and lines denotes relative ratio of each type of CVC patterns obtained from pooled data and developmental curves of them, respectively. The shaded areas indicate periods between onset and offset of the developmental changes. We defined the onsets and offsets as months at which a value of curves exceeded 1/3 and 2/3, respectively.</p
The developmental curve of each fronting pattern in Japanese.
<p>The black, gray and silver lines show developmental curves of the labial-vowel-coronal, labial-vowel-dorsal, and coronal-vowel-dorsal sequences, respectively. The circles, squares and triangles show raw fronting indices of the labial-vowel-coronal, labial-vowel-dorsal and coronal-vowel-dorsal sequences, respectively.</p
The classification of serial order in articulations in the previous and present studies.
<p>(A) The place of articulations for consonants and vowels, and articulatory organs involved in each consonant. Depending on the horizontal position of the tongue, vowels are categorized into three types including front, center and back. This figure illustrates three places of articulations, including labial, coronal and dorsal. Labial consonants are mainly articulated by the lips and jaw. Coronal consonants are mainly articulated by the tongue apex and jaw. Dorsal consonants are mainly articulated by the tongue dorsum and jaw. (B) Three consonant-vowel patterns preferred by infants in early development. Focusing on three consonantal and vowel categories, theoretically speaking, it is possible to produce nine consonant-vowel sequences. However, infants prefer three out of those nine possible sequences: labial-center, coronal-front, and dorsal-back <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078600#pone.0078600-MacNeilage1" target="_blank">[11]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0078600#pone.0078600-MacNeilage2" target="_blank">[12]</a>. (C) Serial order in articulation of consonants in consonant-vowel-consonant(-vowel) sequences. In the present study, focusing on the relationship among articulators producing adjacent consonants, we divided sequences into four categories: (i) Sequences consists of consonants produced at the same place of articulation. (ii) Sequences produced by movements from more anterior place to posterior one. (iii) Sequences consist of coronal and dorsal consonants, which are articulated by the same organ but different places (intra-organ articulations). (iv) Sequences consist of labial and coronal/dorsal consonants, which are articulated by different organs: lips and tongue (inter-organ articulations).</p
The developmental curve of each fronting pattern in English.
<p>The black, gray and silver lines show developmental curves of the labial-vowel-coronal, labial-vowel-dorsal, and coronal-vowel-dorsal sequences, respectively. The circles, squares and triangles show raw fronting indices of the labial-vowel-coronal, labial-vowel-dorsal and coronal-vowel-dorsal sequences, respectively.</p
Programed Self-Decomposition Model And Artificial Life
We had proposed a biological hypothesis "programed self-decomposition (PSD) model" which assumes that a self-decomposition mechanism is programed in each cell of all creatures on the earth and contributes to the restoration of the original state of the terrestrial ecosystem[2--6]. In this article, the overview of the researches on PSD model and the newest results of both biochemical and computer experiments are reported. 1 Programed Self-Decomposition Model 1.1 Restoration of the original state of ecosystem Action of life can hardly be attained without depriving a given substance and energy and occupying a given space from the environment where it takes place. The terrestrial ecosystem forms an open system in the sense that energy is supplied by the sun and wasted heat is released to extraterrestial space. Conversely, it has a characteristic of being almost a closed system in respect that substance and space are both limited. Accordingly, to keep on stably maintaining action of life ..
Precursors of Dancing and Singing to Music in Three- to Four-Months-Old Infants
<div><p>Dancing and singing to music involve auditory-motor coordination and have been essential to our human culture since ancient times. Although scholars have been trying to understand the evolutionary and developmental origin of music, early human developmental manifestations of auditory-motor interactions in music have not been fully investigated. Here we report limb movements and vocalizations in three- to four-months-old infants while they listened to music and were in silence. In the group analysis, we found no significant increase in the amount of movement or in the relative power spectrum density around the musical tempo in the music condition compared to the silent condition. Intriguingly, however, there were two infants who demonstrated striking increases in the rhythmic movements via kicking or arm-waving around the musical tempo during listening to music. Monte-Carlo statistics with phase-randomized surrogate data revealed that the limb movements of these individuals were significantly synchronized to the musical beat. Moreover, we found a clear increase in the formant variability of vocalizations in the group during music perception. These results suggest that infants at this age are already primed with their bodies to interact with music via limb movements and vocalizations.</p></div
Spontaneous vocalizations of infants during the music condition “Go Trippy” by WANICO feat. Jake Smith (red) and in the silent condition where no auditory stimulus was present (blue).
<p>Error bars indicate standard errors (SE) among the participants. (<b>A</b>) No significant difference was found in mean duration of vocalization per minute between the silent and music conditions (Wilcoxon signed-rank test, <i>Z</i> = 1.62, <i>p</i> = 0.11). (<b>B</b>) Typical time series of fundamental (F<sub>0</sub>, black lines) and formant frequencies (F<sub>1</sub> and F<sub>2</sub>, cyan and magenta lines, respectively) within utterances. (<b>C, D</b>) Mean F<sub>0</sub> and F<sub>1</sub> was significantly higher in the music condition than in the silent condition (<i>Z</i> = 2.39, *<i>p</i><0.05; <i>Z</i> = 2.06, *<i>p</i><0.05, respectively). (<b>E, F</b>) There were no significant differences in mean F<sub>2</sub> and SD of F<sub>0</sub> (<i>Z</i> = 1.92, <i>p</i> = 0.06; <i>Z</i> = 1.16, <i>P</i> = 0.25, respectively). (<b>G, H</b>) SD of F<sub>1</sub> and F<sub>2</sub> were significantly higher in the music condition than in the silent condition (<i>Z</i> = 3.43, **<i>p</i><0.001; <i>Z</i> = 3.48, **<i>p</i><0.001, respectively).</p
Significant synchronization in right leg movements of ID1 during the music condition “Everybody” (108.7 BPM) (Video S3).
<p>(<b>A</b>) Sound wave of the auditory stimulus (yellow) with the detected beat onsets (red vertical lines). (<b>B</b>) Observed (left) and phase-randomized (right) position data <i>s</i><sub>pos</sub> (<i>t</i>) along the Y coordinate axis when the infant moved continuously over a period of three seconds (defined as a <i>moving section</i>). (<b>C</b>) Instantaneous phase of the musical beat <i>φ</i><sub>music</sub> (<i>t</i>) calculated from the detected beat onsets. (<b>D</b>) Instantaneous phase of the motion <i>φ</i><sub>motion</sub> (<i>t</i>). (<b>E</b>) Relative phase <i>φ</i><sub>rel</sub> (<i>t</i>) between motion and the musical beat. (<b>F</b>) Circular histograms of <i>φ</i><sub>rel</sub> (<i>t</i>). (<b>G</b>) Monte-Carlo statistics showed that the observed synchronization index (magenta line) was above the 95% confidence interval of the surrogate synchronization indexes (blue lines) calculated from the 10,000 phase-randomized position data: The observed movement was significantly synchronized to the musical beat.</p