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Improved V I Log(gf) Values and Abundance Determinations in the Photospheres of the Sun and Metal-Poor Star HD 84937
New emission branching fraction measurements for 836 lines of the first spectrum of vanadium (V I) are determined from hollow cathode lamp spectra recorded with the National Solar Observatory 1 m Fourier transform spectrometer (FTS) and a high-resolution echelle spectrometer. The branching fractions are combined with recently published radiative lifetimes from laser-induced fluorescence measurements to determine accurate absolute atomic transition probabilities for the 836 lines. The FTS data are also used to extract new hyperfine structure A coefficients for 26 levels of neutral vanadium. These new laboratory data are applied to determine the V abundance in the Sun and metal-poor star HD 84937, yielding log epsilon(V) = 3.956 +/- 0.004 (sigma = 0.037) based on 93 V I lines and log epsilon(V) = 1.89 +/- 0.03 (sigma = 0.07) based on nine Vi lines, respectively, using the Holweger-Muller 1D model. These new V I abundance values for the Sun and HD 84937 agree well with our earlier determinations based upon V II.NASA NNX10AN93GNSF AST-1211055, AST-1211585Astronom
Solid domains in lipid vesicles and scars
The free energy of a crystalline domain coexisting with a liquid phase on a
spherical vesicle may be approximated by an elastic or stretching energy and a
line tension term. The stretching energy generally grows as the area of the
domain, while the line tension term grows with its perimeter. We show that if
the crystalline domain contains defect arrays consisting of finite length grain
boundaries of dislocations (scars) the stretching energy grows linearly with a
characteristic length of the crystalline domain. We show that this result is
critical to understand the existence of solid domains in lipid-bilayers in the
strongly segregated two phase region even for small relative area coverages.
The domains evolve from caps to stripes that become thinner as the line tension
is decreased. We also discuss the implications of the results for other
experimental systems and for the general problem that consists in finding the
ground state of a very large number of particles constrained to move on a fixed
geometry and interacting with an isotropic potential.Comment: 7 pages, 6 eps figure
Angular dependence of domain wall resistivity in SrRuO films
is a 4d itinerant ferromagnet (T 150 K) with
stripe domain structure. Using high-quality thin films of SrRuO we study
the resistivity induced by its very narrow ( nm) Bloch domain walls,
(DWR), at temperatures between 2 K and T as a function of the
angle, , between the electric current and the ferromagnetic domains
walls. We find that which provides the first experimental
indication that the angular dependence of spin accumulation contribution to DWR
is . We expect magnetic multilayers to exhibit a similar
behavior.Comment: 5 pages, 5 figure
Subitizing with Variational Autoencoders
Numerosity, the number of objects in a set, is a basic property of a given
visual scene. Many animals develop the perceptual ability to subitize: the
near-instantaneous identification of the numerosity in small sets of visual
items. In computer vision, it has been shown that numerosity emerges as a
statistical property in neural networks during unsupervised learning from
simple synthetic images. In this work, we focus on more complex natural images
using unsupervised hierarchical neural networks. Specifically, we show that
variational autoencoders are able to spontaneously perform subitizing after
training without supervision on a large amount images from the Salient Object
Subitizing dataset. While our method is unable to outperform supervised
convolutional networks for subitizing, we observe that the networks learn to
encode numerosity as basic visual property. Moreover, we find that the learned
representations are likely invariant to object area; an observation in
alignment with studies on biological neural networks in cognitive neuroscience
Melting of Single Lipid Components in Binary Lipid Mixtures: A Comparison between FTIR Spectroscopy, DSC and Monte Carlo Simulations
Monte Carlo (MC) Simulations, Differential Scanning Calorimetry (DSC) and
Fourier Transform InfraRed (FTIR) spectroscopy were used to study the melting
behavior of single lipid components in two-component membranes of
1,2-Dimyristoyl-D54-sn-Glycero-3-Phosphocholine (DMPC-d54) and
1,2-Distearoyl-sn-Glycero-3-Phosphocholine (DSPC). Microscopic information on
the temperature dependent melting of the single lipid species could be
investigated using FTIR. The microscopic behavior measured could be well
described by the results from the MC simulations. These simulations also
allowed to calculate heat capacity profiles as determined with DSC. These ones
provide macroscopic information about melting enthalpies and entropy changes
which are not accessible with FTIR. Therefore, the MC simulations allowed us to
link the two different experimental approaches of FTIR and DSC.Comment: 12 pages, 5 figures, corrected typo in table 1 in which previously it
said Tm,1 instead of Tm,
Preschoolers' Precision of the Approximate Number System Predicts Later School Mathematics Performance
The Approximate Number System (ANS) is a primitive mental system of nonverbal representations that supports an intuitive sense of number in human adults, children, infants, and other animal species. The numerical approximations produced by the ANS are characteristically imprecise and, in humans, this precision gradually improves from infancy to adulthood. Throughout development, wide ranging individual differences in ANS precision are evident within age groups. These individual differences have been linked to formal mathematics outcomes, based on concurrent, retrospective, or short-term longitudinal correlations observed during the school age years. However, it remains unknown whether this approximate number sense actually serves as a foundation for these school mathematics abilities. Here we show that ANS precision measured at preschool, prior to formal instruction in mathematics, selectively predicts performance on school mathematics at 6 years of age. In contrast, ANS precision does not predict non-numerical cognitive abilities. To our knowledge, these results provide the first evidence for early ANS precision, measured before the onset of formal education, predicting later mathematical abilities
Ontogeny of Numerical Abilities in Fish
Background: It has been hypothesised that human adults, infants, and non-human primates share two non-verbal systems for enumerating objects, one for representing precisely small quantities (up to 3â4 items) and one for representing approximately larger quantities. Recent studies exploiting fishâs spontaneous tendency to join the larger group showed that their ability in numerical discrimination closely resembles that of primates but little is known as to whether these capacities are innate or acquired. Methodology/Principal Findings: We used the spontaneous tendency to join the larger shoal to study the limits of the quantity discrimination of newborn and juvenile guppies. One-day old fish chose the larger shoal when the choice was between numbers in the small quantity range, 2 vs. 3 fish, but not when they had to choose between large numbers, 4 vs. 8 or 4 vs. 12, although the numerical ratio was larger in the latter case. To investigate the relative role of maturation and experience in large number discrimination, fish were raised in pairs (with no numerical experience) or in large social groups and tested at three ages. Forty-day old guppies from both treatments were able to discriminate 4 vs. 8 fish while at 20 days this was only observed in fish grown in groups. Control experiments showed that these capacities were maintained after guppies were prevented from using non numerical perceptual variables that co-vary with numerosity. Conclusions/Significance: Overall, our results suggest the ability of guppies to discriminate small numbers is innate and i
Hand gesture-based interactive puppetry system to assist storytelling for children
© 2016 The Author(s)Digital techniques have been used to assist narrative and storytelling, especially in many pedagogical practices. With the rapid development of HCI techniques, saturated with digital media in their daily lives, young children, demands more interactive learning methods and meaningful immersive learning experiences. In this paper, we propose a novel hand gesture-based puppetry storytelling system which provides a more intuitive and natural human computer interaction method for young children to develop narrative ability in virtual story world. Depth motion sensing and hand gestures control technology is utilized in the implementation of user-friendly interaction. Young players could intuitively use hand gestures to manipulate virtual puppet to perform story and interact with different items in virtual environment to assist narration. Based on the result of the evaluation, this novel digital storytelling system shows positive pedagogical functions on childrenâs narrating ability as well as the competencies of cognitive and motor coordination. The usability of the system is preliminary examined in our test, and the results which showed that young children can benefit from playing with Puppet Narrator
Amicus Brief, Lebron v. Gottlieb Memorial Hospital
Illinois Public Act 82-280, § 2-1706.5, as amended by P.A. 94-677, § 330 (eff. Aug. 25, 2005), and as codified as 735 ILCS 5/2-1706.5(a), imposes a 1 million âcapâ on the noneconomic damages that may be awarded against a hospital, its affiliates, or their employees.
This brief will address two of the questions presented for review by the parties:
1. Does the cap violate the Illinois Constitutionâs prohibition on âspecial legislation,â Art. IV, § 3, because it unnecessarily, arbitrarily, and irrationally grants exceptional benefits and privileges exclusively to certain classes of tort defendants.
2. Does the cap violate the Illinois Constitutionâs guarantee of âequal protection,â Art. I, § 2, because it unnecessarily, arbitrarily, and irrationally imposes extraordinary burdens uniquely upon certain classes and sub-classes of tort plaintiffs
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