6,817 research outputs found
Health Care Reform for Children With Public Coverage
Compares private and public coverage for low-income children. Explores the implications of proposed changes to Medicaid and State Children's Health Insurance Programs and creation of an insurance exchange for their coverage and access to health care
The Role of Consciousness in Memory
Conscious events interact with memory systems in learning, rehearsal and retrieval (Ebbinghaus 1885/1964; Tulving 1985). Here we present hypotheses that arise from the IDA computional model (Franklin, Kelemen and McCauley 1998; Franklin 2001b) of global workspace theory (Baars 1988, 2002). Our primary tool for this exploration is a flexible cognitive cycle employed by the IDA computational model and hypothesized to be a basic element of human cognitive processing. Since cognitive cycles are hypothesized to occur five to ten times a second and include interaction between conscious contents and several of the memory systems, they provide the means for an exceptionally fine-grained analysis of various cognitive tasks. We apply this tool to the small effect size of subliminal learning compared to supraliminal learning, to process dissociation, to implicit learning, to recognition vs. recall, and to the availability heuristic in recall. The IDA model elucidates the role of consciousness in the updating of perceptual memory, transient episodic memory, and procedural memory. In most cases, memory is hypothesized to interact with conscious events for its normal functioning. The methodology of the paper is unusual in that the hypotheses and explanations presented are derived from an empirically based, but broad and qualitative computational model of human cognition
The structure of frontoparallel haptic space is task dependent
In three experiments, we investigated the structure of frontoparallel haptic space. In the first experiment, we asked blindfolded participants to rotate a matching bar so that it felt parallel to the reference bar, the bars could be at various positions in the frontoparallel plane. Large systematic errors were observed, in which orientations that were perceived to be parallel were not physically parallel. In two subsequent experiments, we investigated the origin of these errors. In Experiment 2, we asked participants to verbally report the orientation of haptically presented bars. In this task, participants made errors that were considerably smaller than those made in Experiment 1. In Experiment 3, we asked participants to set bars in a verbally instructed orientation, and they also made errors significantly smaller than those observed in Experiment 1. The data suggest that the errors in the matching task originate from the transfer of the reference orientation to the matching-bar position
Detecting Common Dynamics in Transitory Components
This paper considers VAR/VECM models for variables exhibiting cointegration and common features in the transitory components. While the presence of cointegration reduces the rank of the long-run multiplier matrix, other types of common features lead to rank reduction in the short-run dynamics. These common transitory components arise when linear combination of the first differenced variables in a cointegrated VAR are white noise. This paper offers a reinterpretation of the traditional approach to testing for common feature dynamics, namely checking for a singular covariance matrix for the transitory components. Instead, the matrix of short-run coefficients becomes the focus of the testing procedure thus allowing a wide range of tests for reduced rank in parameter matrices to be potentially relevant tests of common transitory components. The performance of the different methods is illustrated in a Monte Carlo analysis which is then used to reexamine an existing empirical study. Finally, this approach is applied to analyze whether one would observe common dynamics in standard DSGE models.Transitory components, common features, reduced rank, cointegration.
Dimensional Crossover of Dilute Neon inside Infinitely Long Single-Walled Carbon Nanotubes Viewed from Specific Heats
A simple formula for coordinates of carbon atoms in a unit cell of a
single-walled nanotube (SWNT) is presented and the potential of neon (Ne)
inside an infinitely long SWNT is analytically derived under the assumption of
pair-wise Lennard-Jones potential between Ne and carbon atoms. Specific heats
of dilute Ne inside infinitely long (5, 5), (10, 10), (15, 15) and (20, 20)
SWNT's are calculated at different temperatures. It is found that Ne inside
four kinds of nanotubes exhibits 3-dimensional (3D) gas behavior at high
temperature but different behaviors at low temperature: Ne inside (5, 5)
nanotube behaves as 1D gas but inside (10, 10), (15, 15), and (20, 20)
nanotubes behaves as 2D gas. Furthermore, at ultra low temperature, Ne inside
(5, 5) nanotube still displays 1D behavior but inside (10, 10), (15, 15), and
(20, 20) nanotubes behaves as lattice gas.Comment: 10 pages, 5 figure
Quasi-one and two-dimensional transitions of gases adsorbed on nanotube bundles
Grand canonical Monte Carlo simulations have been performed to determine the
adsorption behavior of Ar and Kr atoms on the exterior surface of a rope
(bundle) consisting of many carbon nanotubes. The computed adsorption isotherms
reveal phase transitions associated with the successive creation of quasi-one
dimensional lines of atoms near and parallel to the intersection of two
adjacent nanotubes.Comment: 12 pages, 6 figures, submitted to J. Chem. Phy
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