927 research outputs found
Cross-linguistic views of gesture usage
People have stereotypes about gesture usage. For instance, speakers in East Asia are not supposed to gesticulate, and it is believed that Italians gesticulate more than the British. Despite the prevalence of such views, studies that investigate these stereotypes are scarce. The present study examined peopleĂs views on spontaneous gestures by collecting data from five different countries. A total of 363 undergraduate students from five countries (France, Italy, Japan, the Netherlands and USA) participated in this study. Data were collected through a two-part questionnaire. Part 1 asked participants to rate two characteristics of gesture: frequency and size of gesture for 13 different languages. Part 2 asked them about their views on factors that might affect the production of gestures. The results showed that most participants in this study believe that Italian, Spanish, and American English speakers produce larger gestures more frequently than other language speakers. They also showed that each culture group, even within Europe, put weight on a slightly different aspect of gestures
Coherent oscillations of electrons in tunnel-coupled wells under ultrafast intersubband excitation
Ultrafast intersubband excitation of electrons in tunnell-coupled wells is
studied depending on the structure parameters, the duration of the infrared
pump and the detuning frequency. The temporal dependencies of the photoinduced
concentration and dipole moment are obtained for two cases of transitions: from
the single ground state to the tunnel-coupled excited states and from the
tunnel-coupled states to the single excited state. The peculiarities of
dephasing and population relaxation processes are also taken into account. The
nonlinear regime of the response is also considered when the splitting energy
between the tunnel-coupled levels is renormalized by the photoexcited electron
concentration. The dependencies of the period and the amplitude of oscillations
on the excitation pulse are presented with a description of the nonlinear
oscillations damping.Comment: 8 pages, 12 figure
Optical Conductivity and Electronic Structure of CeRu4Sb12 under High Pressure
Optical conductivity [s(w)] of Ce-filled skutterudite CeRu4Sb12 has been
measured at high pressure to 8 GPa and at low temperature, to probe the
pressure evolution of its electronic structures. At ambient pressure, a
mid-infrared peak at 0.1 eV was formed in s(w) at low temperature, and the
spectral weight below 0.1 eV was strongly suppressed, due to a hybridization of
the f electron and conduction electron states. With increasing external
pressure, the mid-infrared peak shifts to higher energy, and the spectral
weight below the peak was further depleted. The obtained spectral data are
analyzed in comparison with band calculation result and other reported physical
properties. It is shown that the electronic structure of CeRu4Sb12 becomes
similar to that of a narrow-gap semiconductor under external pressure.Comment: 8 pages, 9 figure
Composition of Ices in Low-Mass Extrasolar Planets
We study the formation conditions of icy planetesimals in protoplanetary
disks in order to determine the composition of ices in small and cold
extrasolar planets. Assuming that ices are formed from hydrates, clathrates,
and pure condensates, we calculate their mass fractions with respect to the
total quantity of ices included in planetesimals, for a grid of disk models. We
find that the composition of ices weakly depends on the adopted disk
thermodynamic conditions, and is rather influenced by the initial composition
of the gas phase. The use of a plausible range of molecular abundance ratios
and the variation of the relative elemental carbon over oxygen ratio in the gas
phase of protoplanetary disks, allow us to apply our model to a wide range of
planetary systems. Our results can thus be used to constrain the icy/volatile
phase composition of cold planets evidenced by microlensing surveys,
hypothetical ocean-planets and carbon planets, which could be detected by Corot
or Kepler.Comment: Accepted for publication in The Astrophysical Journa
Changes Over Time in Absolute and Relative Socioeconomic Differences in Smoking: A Comparison of Cohort Studies From Britain, Finland, and Japan
INTRODUCTION: Socioeconomic differences in smoking over time and across national contexts are poorly understood. We assessed the magnitude of relative and absolute social class differences in smoking in cohorts from Britain, Finland and Japan over 5-7 years. METHODS: The British Whitehall II study (n=4350), Finnish Helsinki Health Study (n=6328), and Japanese Civil Servants Study (n=1993) all included employed men and women aged 35-68 at baseline in 1997-2002. Follow-up was in 2003-2007 (mean follow-up 5.1, 6.5 and 3.6 years, respectively). Occupational social class (managers, professionals and clerical employees) was measured at baseline. Current smoking and covariates (age, marital status, body mass index and self-rated health) were measured at baseline and follow-up. We assessed relative social class differences using the Relative Index of Inequality (RII) and absolute differences using the Slope Index of Inequality (SII). RESULTS: Social class differences in smoking were found in Britain and Finland, but not in Japan. Age-adjusted relative differences at baseline ranged from RII 3.08 (95% confidence interval 1.99-4.78) among Finnish men to 2.32 (1.24-4.32) among British women, with differences at follow-up greater by 8-58%. Absolute differences remained stable and varied from SII 0.27 (0.15-0.40) among Finnish men to 0.10 (0.03-0.16) among British women. Further adjustment for covariates had modest effects on inequality indices. CONCLUSIONS: Large social class differences in smoking persisted among British and Finnish men and women, with widening tendencies in relative differences over time. No differences could be confirmed among Japanese men or women
Multipole State of Heavy Lanthanide Filled Skutterudites
We discuss multipole properties of filled skutterudites containing heavy
lanthanide Ln from a microscopic viewpoint on the basis of a seven-orbital
Anderson model. For Ln=Gd, in contrast to naive expectation, quadrupole moments
remain in addition to main dipole ones. For Ln=Ho, we find an exotic state
governed by octupole moment. For Ln=Tb and Tm, no significant multipole moments
appear at low temperatures, while for Ln=Dy, Er, and Yb, dipole and
higher-order multipoles are dominant. We briefly discuss possible relevance of
these multipole states with actual materials.Comment: 5 pages, 3 figure
Anomalous negative excursion of carbon isotope in organic carbon after the last Paleoproterozoic glaciation in North America
Early Paleoproterozoic time (2.5â2.0 Ga) spanned a critical phase in Earth's history, characterized by repeated glaciations and an increase in atmospheric oxygen (the Great Oxidation Event (GOE)). Following the last and most intense glaciation of this period, marine carbonates record a large positive excursion of ÎŽ^(13)C value (termed the âLomagundi eventâ) between about 2.2 and 2.1 Ga coinciding with the global appearances of red beds and sulfates, which suggest an accumulation of high levels of atmospheric oxygen. Here we report the discovery of large negative excursions of ÎŽ^(13)C in organic matter (down to â55â°) from quartzose sandstones (of the Marquette Range and the Huronian Supergroups, North America) intermediate in age between the last Paleoproterozoic glaciation and the possible onset of the Lomagundi event. The negative excursion is concomitant with the appearance of intensely weathered quartzose sandstones, which may represent hot and humid conditions. There are some interpretations that potentially explain the negative excursions: (1) redeposition of older ^(13)C-depleted kerogen, (2) later post-depositional infiltration of oil, (3) active methane productions by methanogens in shallow-marine environments, or (4) dissociation of methane hydrate. If the latter two were the case, they would provide clues for understanding the environmental change connecting the intense glaciation and an increase in oxygen
Scalar order: possible candidate for order parameters in skutterudites
Phenomenological Landau analysis shows that the properties of ordered phases
in some skutterudites are consistently accounted for by a scalar order
parameter which preserves the cubic symmetry, even in the ordered phase. A
universal value is found for the anisotropy ratio of the transition temperature
in a magnetic field, homogeneous magnetization, and induced staggered
magnetization. The difference in magnetic behavior between PrFeP and
PrRuP near their phase transitions is explained within a single
framework. For the low-field phase of PrFeP, the scalar order with
the symmetry can explain (i) the absence of field induced dipoles
perpendicular to the magnetic field, (ii) isotropic magnetic susceptibility in
the ordered phase, (iii) the field angle dependence of the transition
temperature, and (iv) the splitting pattern of the P nuclear magnetic
resonance (NMR) spectra. It is proposed how the order parameter in
SmRuP is identified by NMR analysis of a single crystal.Comment: 4 pages, 4 figure
Spin fluctuations in CuGeO probed by light scattering
We have measured temperature dependence of low-frequency Raman spectra in
CuGeO, and have observed the quasi-elastic scattering in the
polarization above the spin-Peierls transition temperature. We attribute it to
the fluctuations of energy density in the spin system. The magnetic specific
heat and an inverse of the magnetic correlation length can be derived from the
quasi-elastic scattering. The inverse of the magnetic correlation length is
proportional to at high temperatures. We compare the
specific heat with a competing- model. This model cannot explain
quantitatively both the specific heat and the magnetic susceptibility with the
same parameters. The origin of this discrepancy is discussed.Comment: 17 pages, REVTeX, 5 Postscript figures; in press in PR
Enhanced Impurity Scattering due to Quantum Critical Fluctuations
It is shown on the basis of the lowest order perturbation expansion with
respect to critical fluctuations that the critical fluctuations give rise to an
enhancement of the potential scattering of non-magnetic impurities. This
qualitatively accounts for the enhancement of the resistivity due to impurities
which has been observed in variety of systems near the quantum critical point,
while the higher order processes happen to give much larger enhancement as seen
from the Ward identity arguments. The cases with dynamical critical exponent
=2 and =3 are discussed explicitly.Comment: Submitted to J. Phys. Soc. Jpn. on 27 September, 200
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