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Responding to the emotions of others: Age differences in facial expressions and age-specific associations with relational connectedness.
Responding prosocially to the emotion of others may become increasingly important in late life, especially as partners and friends encounter a growing number of losses, challenges, and declines. Facial expressions are important avenues for communicating empathy and concern, and for signaling that help is forthcoming when needed. In a study of young, middle-aged, and older adults, we measured emotional responses (facial expressions, subjective experience, and physiological activation) to a sad, distressing film clip and a happy, uplifting film clip. Results revealed that, relative to younger adults, older adults showed more sadness and confusion/concern facial expressions during the distressing film clip. Moreover, for older adults only, more sadness and fewer disgust facial expressions during the distressing film clip were associated with higher levels of relational connectedness. These findings remained stable when accounting for subjective emotional experience, physiological activation, and trait empathy in response to the film clip. When examining the uplifting film clip, older adults showed more happiness facial expressions relative to younger adults at trend levels. More facial expressions of happiness were associated with higher levels of relational connectedness, but unlike the effect of sadness expressions, this was not moderated by age. These findings underscore an important adaptive social function of facial expressions-particularly in response to the distress of others-in late life. (PsycINFO Database Record (c) 2019 APA, all rights reserved)
A Plasma {\beta} Transition Within a Propagating Flux Rope
We present a 2.5D MHD simulation of a magnetic flux rope (FR) propagating in
the heliosphere and investigate the cause of the observed sharp plasma beta
transition. Specifically, we consider a strong internal magnetic field and an
explosive fast start, such that the plasma beta is significantly lower in the
FR than the sheath region that is formed ahead. This leads to an unusual FR
morphology in the first stage of propagation, while the more traditional view
(e.g. from space weather simulations like Enlil) of a `pancake' shaped FR is
observed as it approaches 1 AU. We investigate how an equipartition line,
defined by a magnetic Weber number, surrounding a core region of a propagating
FR can demarcate a boundary layer where there is a sharp transition in the
plasma beta. The substructure affects the distribution of toroidal flux, with
the majority of the flux remaining in a small core region which maintains a
quasi-cylindrical structure. Quantitatively, we investigate a locus of points
where the kinetic energy density of the relative inflow field is equal to the
energy density of the transverse magnetic field (i.e. effective tension force).
The simulation provides compelling evidence that at all heliocentric distances
the distribution of toroidal magnetic flux away from the FR axis is not linear;
with 80% of the toroidal flux occurring within 40% of the distance from the FR
axis. Thus our simulation displays evidence that the competing ideas of a
pancaking structure observed remotely can coexist with a quasi-cylindrical
magnetic structure seen in situ.Comment: 11 pages of text + 6 figures. Accepted to ApJ on 16 Oct 201
Polar Field Reversal Observations with Hinode
We have been monitoring yearly variation in the Sun's polar magnetic fields
with the Solar Optical Telescope aboard {\it Hinode} to record their evolution
and expected reversal near the solar maximum. All magnetic patches in the
magnetic flux maps are automatically identified to obtain the number density
and magnetic flux density as a function of th total magnetic flux per patch.
The detected magnetic flux per patch ranges over four orders of magnitude
( -- Mx). The higher end of the magnetic flux in the polar
regions is about one order of magnitude larger than that of the quiet Sun, and
nearly that of pores. Almost all large patches ( Mx) have the
same polarity, while smaller patches have a fair balance of both polarities.
The polarity of the polar region as a whole is consequently determined only by
the large magnetic concentrations. A clear decrease in the net flux of the
polar region is detected in the slow rising phase of the current solar cycle.
The decrease is more rapid in the north polar region than in the south. The
decrease in the net flux is caused by a decrease in the number and size of the
large flux concentrations as well as the appearance of patches with opposite
polarity at lower latitudes. In contrast, we do not see temporal change in the
magnetic flux associated with the smaller patches ( Mx) and that of
the horizontal magnetic fields during the years 2008--2012.Comment: 21 pages, 7 figures. Accepted for publication in Ap
A Symmetric Generalization of Linear B\"acklund Transformation associated with the Hirota Bilinear Difference Equation
The Hirota bilinear difference equation is generalized to discrete space of
arbitrary dimension. Solutions to the nonlinear difference equations can be
obtained via B\"acklund transformation of the corresponding linear problems.Comment: Latex, 12 pages, 1 figur
Direct observation of a highly spin-polarized organic spinterface at room temperature
The design of large-scale electronic circuits that are entirely
spintronics-driven requires a current source that is highly spin-polarised at
and beyond room temperature, cheap to build, efficient at the nanoscale and
straightforward to integrate with semiconductors. Yet despite research within
several subfields spanning nearly two decades, this key building block is still
lacking. We experimentally and theoretically show how the interface between Co
and phthalocyanine molecules constitutes a promising candidate. Spin-polarised
direct and inverse photoemission experiments reveal a high degree of spin
polarisation at room temperature at this interface. We measured a magnetic
moment on the molecules's nitrogen pi orbitals, which substantiates an
ab-initio theoretical description of highly spin-polarised charge conduction
across the interface due to differing spinterface formation mechanims in each
spin channel. We propose, through this example, a recipe to engineer simple
organic-inorganic interfaces with remarkable spintronic properties that can
endure well above room temperature
Integrable equations in nonlinear geometrical optics
Geometrical optics limit of the Maxwell equations for nonlinear media with
the Cole-Cole dependence of dielectric function and magnetic permeability on
the frequency is considered. It is shown that for media with slow variation
along one axis such a limit gives rise to the dispersionless Veselov-Novikov
equation for the refractive index. It is demonstrated that the Veselov-Novikov
hierarchy is amenable to the quasiclassical DBAR-dressing method. Under more
specific requirements for the media, one gets the dispersionless
Kadomtsev-Petviashvili equation. Geometrical optics interpretation of some
solutions of the above equations is discussed.Comment: 33 pages, 7 figure
Hugoniot measurement of diamond under laser shock compression up to 2 Tpa
Copyright 2006 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 13(5), 052705, 2006 and may be found at http://dx.doi.org/10.1063/1.220519
Functional characterization of a melon alcohol acyl-transferase gene family involved in the biosynthesis of ester volatiles. Identification of the crucial role of a threonine residue for enzyme activity
Volatile esters, a major class of compounds contributing to the aroma of many fruit, are synthesized by
alcohol acyl-transferases (AAT). We demonstrate here that, in Charentais melon (Cucumis melo var.
cantalupensis), AAT are encoded by a gene family of at least four members with amino acid identity ranging
from 84% (Cm-AAT1/Cm-AAT2) and 58% (Cm-AAT1/Cm-AAT3) to only 22% (Cm-AAT1/Cm-AAT4).
All encoded proteins, except Cm-AAT2, were enzymatically active upon expression in yeast and show
differential substrate preferences. Cm-AAT1 protein produces a wide range of short and long-chain acyl
esters but has strong preference for the formation of E-2-hexenyl acetate and hexyl hexanoate. Cm-AAT3
also accepts a wide range of substrates but with very strong preference for producing benzyl acetate.
Cm-AAT4 is almost exclusively devoted to the formation of acetates, with strong preference for cinnamoyl
acetate. Site directed mutagenesis demonstrated that the failure of Cm-AAT2 to produce volatile esters is
related to the presence of a 268-alanine residue instead of threonine as in all active AAT proteins. Mutating
268-A into 268-T of Cm-AAT2 restored enzyme activity, while mutating 268-T into 268-A abolished
activity of Cm-AAT1. Activities of all three proteins measured with the prefered substrates sharply increase
during fruit ripening. The expression of all Cm-AAT genes is up-regulated during ripening and inhibited in
antisense ACC oxidase melons and in fruit treated with the ethylene antagonist 1-methylcyclopropene
(1-MCP), indicating a positive regulation by ethylene. The data presented in this work suggest that the
multiplicity of AAT genes accounts for the great diversity of esters formed in melon
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