644 research outputs found
Effect of Perceptual Factors in the Relationship between a Referent and Objects around the Referent on Young Childrenās Interpretation of Word Meanings
The purpose of this study was to examine the effect of perceptual factors in the relationship between a referent and objects around the referent on young childrenās interpretation of word meanings. Participants were 60 children aged 5 years (35 girls, 25 boys; mean age: 5 years 7 months). They participated in a task of interpreting the meaning of nonsense words with high and low inclusiveness conditions. Participants were likely to perceive that objects around the target object included the target object in the high inclusiveness condition. On the other hand, they were not likely to do so in the low inclusiveness condition. As a result, in the high inclusiveness condition, they were likely to speculate that the nonsense label was the name for the target taken together with the object around the target, while in the low inclusiveness condition, they understood it as the name of the target item. The results showed that detailed perceptual factors, such as inclusiveness of the referent and objects around the referent, affected childrenās language development process
Cepheids and other short-period variables near the Galactic Centre
We report the result of our near-infrared survey of short-period variable
stars (P<60d) in a field-of-view of 20'x30' towards the Galactic Centre.
Forty-five variables are discovered and we classify the variables based on
their light curve shapes and other evidence. In addition to 3 classical
Cepheids reported previously, we find 16 type II Cepheids, 24 eclipsing
binaries, one pulsating star with P=0.265d (RR Lyr or delta Sct) and one
Cepheid-like variable whose nature is uncertain. Eclipsing binaries are
separated into the foreground objects and those significantly obscured by
interstellar extinction. One of the reddened binaries contains an O-type
supergiant and its light curve indicates an eccentric orbit. We discuss the
nature and distribution of type II Cepheids as well as the distance to the
Galactic Centre based on these Cepheids and other distance indicators. The
estimates of R0(GC) we obtained based on photometric data agree with previous
results obtained with kinematics of objects around the GC. Furthermore, our
result gives a support to the reddening law obtained by Nishiyama and
collaborators, A(Ks)/E(H-Ks)=1.44, because a different reddening law would
result in a rather different distance estimate.Comment: 13 pages, 10 figures, 7tables, accepted for publication in MNRA
Generating Visual Information for Motion Sickness Reduction Using a Computational Model Based on SVC Theory
With the advancements in automated driving, there is concern that motion
sickness will increase as non-driving-related tasks increase. Therefore,
techniques to reduce motion sickness have drawn much attention. Research
studies have attempted to estimate motion sickness using computational models
for controlling it. Among them, a computational model for estimating motion
sickness incidence (MSI) with visual information as input based on subjective
vertical conflict theories was developed. In addition, some studies attempt to
mitigate motion sickness by controlling visual information. In particular, it
has been confirmed that motion sickness is suppressed by matching head movement
and visual information. However, there has been no research on optimal visual
information control that suppresses motion sickness in vehicles by utilizing
mathematical models. We, therefore, propose a method for generating optimal
visual information to suppress motion sickness caused from vehicle motion by
utilizing a motion sickness model with vestibular and visual inputs. To confirm
the effectiveness of the proposed method, we investigated changes in the motion
sickness experienced by the participants according to the visual information
displayed on the head-mounted display. The experimental results suggested that
the proposed method mitigates the motion sickness of the participants
Effect of Objects Surrounding a Referent on Young Childrenās Interpretation of Word Meanings
This study examined the effect of objects surrounding a referent on young children's interpretation of word meanings. In Study 1, 50 children aged 5 years (28 females, 22 males; mean age: 5 years 8 months, SD: 2.37) took part in a novel label task wherein they were given a novel word for a target object with its surrounding object in two conditions, namely, high ordinariness (e.g., an elephant in a cage) or low ordinariness (e.g., an elephant riding in a car). The participants in both conditions tended to interpret the novel word as a name denoting the target object and its surrounding object. In Study 2, which used the same task, 50 children aged 5 yearsĀ (26 females, 24 males; mean age: 5 years 8 months, SD: 2.47) were given a novel word for a target object with its surrounding object in two conditions, namely high proximity (e.g., an elephant in a cage) or low proximity (e.g., an elephant near a tree). Participants in the high proximity condition tended to interpret the novel word as referring to a name that incorporated the target item and its surrounding object. In contrast, the participants in low proximity condition tended to interpret the novel word as referring to the name of the target object only (e.g., āelephantā). These results suggest that perceptual factors, such as the proximity of the referent and its surrounding objects, influence word learning in young children. The findings are discussed with respect to young childrenās word learning in everyday life.Ā
Specific modification at the C-terminal lysine residue of the green fluorescent protein variant, GFPuv, expressed in Escherichia coli
Green fluorescent protein (GFP) is amenable to recombinant expression in various kinds of cells and is widely used in life science research. We found that the recombinant expression of GFPuv, a commonly-used mutant of GFP, in E. coli produced two distinct molecular species as judged by in-gel fluorescence SDS-PAGE. These molecular species, namely form I and II, could be separately purified by anion-exchange chromatography without any remarkable differences in the fluorescence spectra. Mass spectrometric analyses revealed that the molecular mass of form I is almost the same as the calculated value, while that of form II is approximately 1 Da larger than that of form I. Further mass spectrometric top-down sequencing pinpointed the modification in GFPuv form II, where the epsilon-amino group of the C-terminal Lys238 residue is converted into the hydroxyl group. No equivalent modification was observed in the native GFP in jellyfish Aequorea victoria, suggesting that this modification is not physiologically relevant. Crystal structure analysis of the two species verified the structural identity of the backbone and the vicinity of the chromophore. The modification found in this study may also be generated in other GFP variants as well as in other recombinant expression systems
Near-infrared circular polarization survey in star-forming regions : Correlations and trends
We have conducted a systematic near-infrared circular polarization (CP) survey in star-forming regions, covering high-mass, intermediate-mass, and low-mass young stellar objects. All the observations were made using the SIRPOL imaging polarimeter on the Infrared Survey Facility 1.4 m telescope at the South African Astronomical Observatory. We present the polarization properties of 10 sub-regions in 6 star-forming regions. The polarization patterns, extents, and maximum degrees of linear and circular polarizations are used to determine the prevalence and origin of CP in the star-forming regions. Our results show that the CP pattern is quadrupolar in general, the CP regions are extensive, up to 0.65 pc, the CP degrees are high, up to 20%, and the CP degrees decrease systematically from high- to low-mass young stellar objects. The results are consistent with dichroic extinction mechanisms generating the high degrees of CP in star-forming regions.Peer reviewe
Distortion of Magnetic Fields in a Starless Core II: 3D Magnetic Field Structure of FeSt 1-457
Three dimensional (3D) magnetic field information on molecular clouds and
cores is important for revealing their kinematical stability (magnetic support)
against gravity which is fundamental for studying the initial conditions of
star formation. In the present study, the 3D magnetic field structure of the
dense starless core FeSt 1-457 is determined based on the near-infrared
polarimetric observations of the dichroic polarization of background stars and
simple 3D modeling. With an obtained angle of line-of-sight magnetic
inclination axis of and previously
determined plane-of-sky magnetic field strength of
, the total magnetic field strength for FeSt 1-457 is derived to be
. The critical mass of FeSt 1-457, evaluated using
both magnetic and thermal/turbulent support is
, which is identical to the observed core mass, . We thus conclude that the stability of
FeSt 1-457 is in a condition close to the critical state. Without infalling gas
motion and no associated young stars, the core is regarded to be in the
earliest stage of star formation, i.e., the stage just before the onset of
dynamical collapse following the attainment of a supercritical condition. These
properties would make FeSt 1-457 one of the best starless cores for future
studies of the initial conditions of star formation.Comment: Accepted to the Astrophysical Journal (ApJ
The Distance to the Galactic Center Derived From Infrared Photometry of Bulge Red Clump Stars
On the basis of the near infrared observations of bulge red clump stars near
the Galactic center, we have determined the galactocentric distance to be R_0 =
7.52 +- 0.10 (stat) +- 0.35 (sys) kpc. We observed the red clump stars at |l| <
1.0 deg and 0.7 deg < |b| < 1.0 deg with the IRSF 1.4 m telescope and the
SIRIUS camera in the H and Ks bands. After extinction and population
corrections, we obtained (m - M)_0 = 14.38 +- 0.03 (stat) +- 0.10 (sys). The
statistical error is dominated by the uncertainty of the intrinsic local red
clump stars' luminosity. The systematic error is estimated to be +- 0.10
including uncertainties in extinction and population correction, zero-point of
photometry, and the fitting of the luminosity function of the red clump stars.
Our result, R_0 = 7.52 kpc, is in excellent agreement with the distance
determined geometrically with the star orbiting the massive black hole in the
Galactic center. The recent result based on the spatial distribution of
globular clusters is also consistent with our result. In addition, our study
exhibits that the distance determination to the Galactic center with the red
clump stars, even if the error of the population correction is taken into
account, can achieve an uncertainty of about 5%, which is almost the same level
as that in recent geometrical determinations.Comment: 14 pages, 4 figures, accepted by Ap
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