1,950 research outputs found
From sensorimotor dependencies to perceptual practices: making enactivism social
Proponents of enactivism should be interested in exploring what notion of action best captures the type of action-perception link that the view proposes, such that it covers all the aspects in which our doings constitute and are constituted by our perceiving. This article proposes and defends the thesis that the notion of sensorimotor dependencies is insufficient to account for the reality of human perception, and that the central enactive notion should be that of perceptual practices. Sensorimotor enactivism is insufficient because it has no traction on socially dependent perceptions, which are essential to the role and significance of perception in our lives. Since the social dimension is a central desideratum in a theory of human perception, enactivism needs a notion that accounts for such an aspect. This article sketches the main features of the Wittgenstein-inspired notion of perceptual practices as the central notion to understand perception. Perception, I claim, is properly understood as woven into a type of social practices that includes food, dance, dress, music, etc. More specifically, perceptual practices are the enactment of culturally structured, normatively rich techniques of commerce of meaningful multi- and inter-modal perceptible material. I argue that perceptual practices explain three central features of socially dependent perception: attentional focus, aspects’ saliency, and modal-specific harmony-like relations
Raman frequency shift in oxygen functionalized carbon nanotubes
In terms of lattice dynamics theory, we study the vibrational properties of
the oxygen-functionalized single wall carbon nanotubes (O-SWCNs). Due to the
C-O and O-O interactions, many degenerate phonon modes are split and even some
new phonon modes are obtained, different from the bare SWCNs. A distinct Raman
shift is found in both the radial breathing mode and G modes, depending not
only on the tube diameter and chirality but also on oxygen coverage and
adsorption configurations. With the oxygen coverage increasing, interesting, a
nonmonotonic up- and down-shift is observed in G modes, which is contributed to
the competition between the bond expansion and contraction, there coexisting in
the functionalized carbon nanotube.Comment: 4 pages, 3 figures, 1 tabl
Band gap engineering by functionalization of BN sheet
From first principles calculations, we investigate the stability and physical
properties of single layer h-BN sheet chemically functionalized by various
groups viz. H, F, OH, CH3, CHO, CN, NH2 etc. We find that full
functionalization of h-BN sheet with these groups lead to decrease in its
electronic band gap, albeit to different magnitudes varying from 0.3 eV to 3.1
eV, depending upon the dopant group. Functionalization by CHO group, in
particular, leads to a sharp decrease in the electronic band gap of the
pristine BN sheet to ~ 0.3 eV, which is congenial for its usage in transistor
based devices. The phonon calculations on these sheets show that frequencies
corresponding to all their vibrational modes are real (positive), thereby
suggesting their inherent stability. The chemisorption energies of these groups
to the B and N atoms of the sheet are found to lie in the range of 1.5 -6 eV.Comment: 15 pages, 2 figures PRB(submitted
Egalitarian justice and expected value
According to all-luck egalitarianism, the differential distributive effects of both brute luck, which defines the outcome of risks which are not deliberately taken, and option luck, which defines the outcome of deliberate gambles, are unjust. Exactly how to correct the effects of option luck is, however, a complex issue. This article argues that (a) option luck should be neutralized not just by correcting luck among gamblers, but among the community as a whole, because it would be unfair for gamblers as a group to be disadvantaged relative to non-gamblers by bad option luck; (b) individuals should receive the warranted expected results of their gambles, except insofar as individuals blamelessly lacked the ability to ascertain which expectations were warranted; and (c) where societal resources are insufficient to deliver expected results to gamblers, gamblers should receive a lesser distributive share which is in proportion to the expected results. Where all-luck egalitarianism is understood in this way, it allows risk-takers to impose externalities on non-risk-takers, which seems counterintuitive. This may, however, be an advantage as it provides a luck egalitarian rationale for assisting ‘negligent victims’
Toward Citizen Centricity: Leveraging the Citizens Academy to Foster Inclusive, Sustainable, and Generative Civic Engagement in Midland, MI
This service learning project aims to utilize positive psychology research to foster inclusive, sustainable, and generative civic engagement among residents of Midland, Michigan. We conceptualize civic engagement as an outgrowth of social capital, and we leverage the constructs of mattering, fairness, belonging, and bridging to offer positive interventions aimed at increasing Midland’s social capital. Specifically, we propose several changes to evolve the city government’s existing educational civic leadership program called the Citizens Academy. First, we suggest adjusting the academy’s recruitment process to expand access and inclusion by increasing the number and diversity of participants. Second, we introduce a more participatory and citizen-centered approach to the program content that builds on Midland’s four strategic pillars as a guiding framework. We offer four positive psychology-based exercises to be interwoven into the Citizens Academy curriculum: Strengths and Values, Community Exploration Guide, Citizen-to-Citizen Coaching, and Storytelling. Third, we recommend a Civic Engagement Scale as a simple tool to measure initial outcomes. It is our hope that this service learning project will serve not only as an initial catalyst for Midland’s goal of increasing civic engagement, but as a model for other cities and communities looking to utilize the science of positive psychology to effect large-scale change
Thermal depinning of fluxons in discrete Josephson rings
We study the thermal depinning of single fluxons in rings made of Josephson
junctions. Due to thermal fluctuations a fluxon can be excited from its energy
minima and move through the array, causing a voltage across each junction. We
find that for the initial depinning, the fluxon behaves as a single particle
and follows a Kramers-type escape law. However, under some conditions this
single particle description breaks down. At low values of the discreteness
parameter and low values of the damping, the depinning rate is larger than the
single particle result would suggest. In addition, for some values of the
parameters the fluxon can undergo low-voltage diffusion before switching to the
high-voltage whirling mode. This type of diffusion is similar to phase
diffusion in a single junction, but occurs without frequency-dependent damping.
We study the switching to the whirling state as well
Spin-dependent resonant tunneling through semimetallic ErAs quantum wells
Resonant tunneling through semimetallic ErAs quantum wells embedded in GaAs
structures with AlAs barriers was recently found to exhibit an intriguing
behavior in magnetic fields which is explained in terms of tunneling selection
rules and the spin-polarized band structure including spin-orbit coupling.Comment: 4 pages, figures supplied as self-unpacking figures.uu, uses
epsfig.sty to incorporate figures in preprin
Cortical Thickness and Subcortical Gray Matter Reductions in Neuropsychiatric Systemic Lupus Erythematosus
Within systemic lupus erythematosus (SLE) patients can be divided into groups with and without central nervous system involvement, the latter being subcategorized as neuropsychiatric systemic lupus erythematosus (NPSLE). While a number of research groups have investigated NPSLE, there remains a lack of consistent application of this diagnostic criteria within neuroimaging studies. Previous neuroimaging research suggests that SLE patients have reduced subcortical and regional gray matter volumes when compared to controls, and that these group differences may be driven by SLE patients with neuropsychiatric symptoms. The current study sought to compare measures of cortical thickness and subcortical structure volume between NPSLE, SLE, and healthy controls. We hypothesized that patients with NPSLE (N = 21) would have thinner cortex and reduced subcortical gray matter volumes when compared to SLE (N = 16) and control subjects (N = 21). All subjects underwent MRI examinations on a 1.5 Tesla Siemens Sonata scanner. Anatomical reconstruction and segmentation were performed using the FreeSurfer image analysis suite. Cortical and subcortical volumes were extracted from FreeSurfer and analyzed for group differences, controlling for age. The NPSLE group exhibited decreased cortical thickness in clusters of the left frontal and parietal lobes as well as in the right parietal and occipital lobes compared to control subjects. Compared to the SLE group, the NPSLE group exhibited comparable thinning in clusters of the frontal and temporal lobes. Controlling for age, we found that between group effects for subcortical gray matter structures were significant for the thalamus (F = 3.06, p = .04), caudate nucleus (F = 3.19, p = .03), and putamen (F = 4.82, p = .005). These results clarify previous imaging work identifying cortical atrophy in a mixed SLE and NPSLE group, and suggest that neuroanatomical abnormalities are specific to SLE patients diagnosed with neuropsychiatric symptoms. Future work should help elucidate the underlying mechanisms underlying the emerging neurobiological profile seen in NPSLE, as well as clarify the apparent lack of overlap between cortical thinning and functional activation results and other findings pointing to increased functional activation during cognitive tasks
Impact of time-ordered measurements of the two states in a niobium superconducting qubit structure
Measurements of thermal activation are made in a superconducting, niobium
Persistent-Current (PC) qubit structure, which has two stable classical states
of equal and opposite circulating current. The magnetization signal is read out
by ramping the bias current of a DC SQUID. This ramping causes time-ordered
measurements of the two states, where measurement of one state occurs before
the other. This time-ordering results in an effective measurement time, which
can be used to probe the thermal activation rate between the two states.
Fitting the magnetization signal as a function of temperature and ramp time
allows one to estimate a quality factor of 10^6 for our devices, a value
favorable for the observation of long quantum coherence times at lower
temperatures.Comment: 14 pages, 4 figure
Multi-component Transparent Conducting Oxides: Progress in Materials Modelling
Transparent conducting oxides (TCOs) play an essential role in modern
optoelectronic devices through their combination of electrical conductivity and
optical transparency. We review recent progress in our understanding of
multi-component TCOs formed from solid-solutions of ZnO, In2O3, Ga2O3 and
Al2O3, with a particular emphasis on the contributions of materials modelling,
primarily based on Density Functional Theory. In particular, we highlight three
major results from our work: (i) the fundamental principles governing the
crystal structures of multi-component oxide structures including (In2O3)(ZnO)n,
named IZO, and (In2O3)m(Ga2O3)l(ZnO)n, named IGZO; (ii) the relationship
between elemental composition and optical and electrical behaviour, including
valence band alignments; (iii) the high-performance of amorphous oxide
semiconductors. From these advances, the challenge of the rational design of
novel electroceramic materials is discussed.Comment: Part of a themed issue of Journal of Physics: Condensed Matter on
"Semiconducting Oxides". In Press (2011
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