21,541 research outputs found
Real Estate Agent Remarks: Help or Hype?
This article groups the remarks of a multiple listing service listing into common themes and then uses a hedonic pricing model to determine whether such comments are priced in a meaningful way. The comments provide information on the motivation of the seller, location of the property and physical improvements or defects. Most of the comments analyzed are statistically significant. Negative comments are associated with lower sales prices suggesting the helpful nature of comments. Some of the positive comments, however, including "new paint" and "good location" are also associated with lower sales prices suggesting that some comments may be better classified as hype.
Does alpha phase modulate visual target detection? Three experiments with tACS-phase-based stimulus presentation
In recent years, the influence of alpha (7â13 Hz) phase on visual processing has received a lot of attention. Magnetoâ/encephalography (M/EEG) studies showed that alpha phase indexes visual excitability and task performance. Studies with transcranial alternating current stimulation (tACS) aim to modulate oscillations and causally impact task performance. Here, we applied right occipital tACS (O2 location) to assess the functional role of alpha phase in a series of experiments. We presented visual stimuli at different preâdetermined, experimentally controlled, phases of the entraining tACS signal, hypothesizing that this should result in an oscillatory pattern of visual performance in specifically left hemifield detection tasks. In experiment 1, we applied 10 Hz tACS and used separate psychophysical staircases for six equidistant tACSâphase conditions, obtaining contrast thresholds for detection of visual gratings in left or right hemifield. In experiments 2 and 3, tACS was at EEGâbased individual peak alpha frequency. In experiment 2, we measured detection rates for gratings with (pseudoâ)fixed contrast. In experiment 3, participants detected brief luminance changes in a customâbuilt LED device, at eight equidistant alpha phases. In none of the experiments did the primary outcome measure over phase conditions consistently reflect a oneâcycle sinusoid. However, post hoc analyses of reaction times (RT) suggested that tACS alpha phase did modulate RT for specifically left hemifield targets in both experiments 1 and 2 (not measured in experiment 3). This observation requires future confirmation, but is in line with the idea that alpha phase causally gates visual inputs through cortical excitability modulation
Electroweak Symmetry Breaking From Monopole Condensation
We examine models where massless chiral fermions with both "electric" and
"magnetic" hypercharges could form condensates. When some of the fermions are
also electroweak doublets such condensates can break the electroweak gauge
symmetry down to electromagnetism in the correct way. Since ordinary
hypercharge is weakly coupled at the TeV scale, magnetic hypercharge is
strongly coupled and can potentially drive the condensation. Such models are
similar to technicolor, but with hypercharge playing the role of the
technicolor gauge group, so the standard model gauge group breaks itself. A
heavy top mass can be generated via the Rubakov-Callan effect and could thus
decouple the scale of flavor physics from the electroweak scale.Comment: Absence of pseudo-Goldstone bosons explain, discussion of the role of
flavor physics clarified, other minor changes. References adde
The Photonic Lantern
Photonic lanterns are made by adiabatically merging several single-mode cores
into one multimode core. They provide low-loss interfaces between single-mode
and multimode systems where the precise optical mapping between cores and
individual modes is unimportant.Comment: 45 pages; article unchanged, accepted for publication in Advances in
Optics and Photonic
Remote sensing in Iowa agriculture: Identification and classification of Iowa's crops, soils and forestry resources using ERTS-1 and complimentary underflight imagery
There are no author-identified significant results in this report
Analisis Produksi dan Pendapatan USAhatani Kacang Tanah di Kabupaten Tapanuli Utara (Studi Kasus: Desa Banuaji IV, Kecamatan Adiankoting)
Penelitian ini bertujuan untuk mengetahui sistem USAhatani kacang tanah, tingkat produksi kacang tanah, faktor-faktor yang mempengaruhi tingkat produksi dan pendapatan USAhatani kacang tanah, serta layak atau tidaknya USAhatani kacang tanah dikembangkan di Desa Banuaji IV, Kecamatan Adiankoting, Kabupaten Tapanuli Utara. Pengambilan sampel dilakukan secara simple random sampling dengan jumlah sampel 30 KK berasal dari 255 KK. Metode penelitian yang digunakan adalah: skoring; analisis data deskriptif; Fungsi produksi Cobb-Douglass dan regresi linear berganda ; Analisis Usahatani rasio R/C. Hasil penelitian menunjukkan sistem USAhatani kacang tanah belum sesuai dengan sistem USAhatani anjuran, tingkat produksi kacang tanah tergolong rendah, faktor-faktor produksi yang mempengaruhi tingkat produksi kacang tanah adalah pupuk Phonska, TSP dan jumlah tenaga kerja, sementara faktor biaya produksi yang berpengarh nyata terhadap pendapatan USAhatani kacang tanah adalah biaya penyusutan peralatan, USAhatani kacang tanah layak dikembangkan di lokasi penelitian
Influence of FK 506 (tacrolimus) on circulating CD4 <sup>+</sup> t cells expressing cd25 and cd45ra antigens in 19 patients with chronic progressive multiple sclerosis participating in an open label drug safety trial
We have taken the opportunity of a clinical trial of the potential efficacy and safety of FK 506 (tacrolimus) in chronic progressive multiple sclerosis (MS) to examine the influence of this potent new immunosuppressant on circulating T-lymphocytes in an otherwise healthy non-transplant population. Peripheral blood levels of subsets of CD4+ T lymphocytes expressing the activation molecule interleukin-2 receptor (p55 α chain; CD25) or the CD45RA isoform were determined sequentially in 19 patients that were treated continuously with oral FK 506 (starting dose 0.15 mg/kg/day) for 12 months. No significant change in the proportion of circulating CD25 + CD4+ cells was observed over the study period in which the mean trough plasma FK 506 level rose from 0.3 ±0.2 to 0.5 ±0.4 ng/ml. There was also no significant effect of FK 506 on the percentage of CD45RA + CD4 + cells in the peripheral blood at 12 months compared with pretreatment values. Analysis of a subgroup of 7 patients, who showed a sustained reduction in CD25 + CD4+ cells and a reciprocal increase in CD45RA* CD4 * cells for at least 6 months after start of treatment, did not reveal any difference in disability at one year compared with the treatment group as a whole. The side effects of FK 506 were mild and the overall degree of disability estimated by the mean Kurtzke expanded disability status scale (EDSS) score or the ambulation index did not deteriorate significantly in the 19 patients studied over the 12 months of FK 506 administration. © 1994 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted
Two-dimensional soliton cellular automaton of deautonomized Toda-type
A deautonomized version of the two-dimensional Toda lattice equation is
presented. Its ultra-discrete analogue and soliton solutions are also
discussed.Comment: 11 pages, LaTeX fil
Ground state of a large number of particles on a frozen topography
Problems consisting in finding the ground state of particles interacting with
a given potential constrained to move on a particular geometry are surprisingly
difficult. Explicit solutions have been found for small numbers of particles by
the use of numerical methods in some particular cases such as particles on a
sphere and to a much lesser extent on a torus. In this paper we propose a
general solution to the problem in the opposite limit of a very large number of
particles M by expressing the energy as an expansion in M whose coefficients
can be minimized by a geometrical ansatz. The solution is remarkably universal
with respect to the geometry and the interaction potential. Explicit solutions
for the sphere and the torus are provided. The paper concludes with several
predictions that could be verified by further theoretical or numerical work.Comment: 9 pages, 9 figures, LaTeX fil
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