32,646 research outputs found
Computation of the order low-energy constants with tensor sources
We present the results of calculations of the and order
low-energy constants for the chiral Lagrangian with tensor sources for both two
and three flavors of pseudoscalar mesons. This is a generalization of our
previous work on similar calculations without tensor sources in terms of the
quark self-energy , based on the first principle derivation of the
low-energy effective Lagrangian and computation of the low-energy constants
with some rough approximations. With the help of partial integration and some
epsilon relations, we find that some order operators with tensor sources
appearing in the literature are related to each other. That leaves 98
independent terms for -flavor, 92 terms for three-flavor, and 65 terms for
two-flavor cases. We also find that the odd-intrinsic-parity chiral Lagrangian
with tensor sources cannot independently exist in any order of low-energy
expansion.Comment: 29 page
Spatio-Temporal Sentiment Hotspot Detection Using Geotagged Photos
We perform spatio-temporal analysis of public sentiment using geotagged photo
collections. We develop a deep learning-based classifier that predicts the
emotion conveyed by an image. This allows us to associate sentiment with place.
We perform spatial hotspot detection and show that different emotions have
distinct spatial distributions that match expectations. We also perform
temporal analysis using the capture time of the photos. Our spatio-temporal
hotspot detection correctly identifies emerging concentrations of specific
emotions and year-by-year analyses of select locations show there are strong
temporal correlations between the predicted emotions and known events.Comment: To appear in ACM SIGSPATIAL 201
Bending instability characteristics of double-walled carbon nanotubes
The bending instability characteristics of double-walled carbon nanotubes (DWNTs) of various configurations are studied using a hybrid approach in which the deformation-induced increase of the intratube interaction energy is modeled with the bending deformation energy using the elastic theory of beams. The intertube interaction energy is calculated using the van der Waals interatomic potential. This study shows that the bending instability may take place through the formation of a single kink in the midpoint of a DWNT or two kinks, placed symmetrically about the midpoint, depending on both the tube length and diameter. The double-kink mode is more favorable for longer DWNTs with the same diameter, and there exists a threshold length for a fixed diameter, below which the single-kink mode occurs at the onset of the bending instability and above which the double-kink mode prevails. The onset characteristic of bending instability is determined by the effectiveness of the intertube interaction in transferring the load from the outer tube onto the inner tube, and the load-transfer effectiveness increases with the increasing tube length. For a fixed length/diameter ratio, the load-transfer effectiveness is found to decrease with the increasing diameter for smaller tubes while it increases for larger tubes, and, thus, the double-kink mode can prevail for both small DWNTs and large DWNTs. ©2005 The American Physical Society.published_or_final_versio
Real Scalar Field Scattering with Polynomial Approximation around Schwarzschild-de Sitter Black-hole
As one of the fitting methods, the polynomial approximation is effective to
process sophisticated problem. In this paper, we employ this approach to handle
the scattering of scalar field around the Schwarzschild-de Sitter black-hole.
The complex relationship between tortoise coordinate and radial coordinate is
replaced by the approximate polynomial. The Schrdinger-like equation,
the real boundary conditions and the polynomial approximation construct a full
Sturm-Liouville type problem. Then this boundary value problem can be solved
numerically according to two limiting cases: the first one is the Nariai
black-hole whose horizons are close to each other, the second one is when the
horizons are widely separated. Compared with previous results (Brevik and
Tian), the field near the event horizon and cosmological horizon can have a
better description.Comment: revtex4 source file, 11 pages, 8 figure
Recommended from our members
Ozone Inhalation Attenuated the Effects of Budesonide on Aspergillus fumigatus-Induced Airway Inflammation and Hyperreactivity in Mice.
Inhaled glucocorticoids form the mainstay of asthma treatment because of their anti-inflammatory effects in the lung. Exposure to the air pollutant ozone (O3) exacerbates chronic airways disease. We and others showed that presence of the epithelial-derived surfactant protein-D (SP-D) is important in immunoprotection against inflammatory changes including those induced by O3 inhalation in the airways. SP-D synthesis requires glucocorticoids. We hypothesized here that O3 exposure impairs glucocorticoid responsiveness (including SP-D production) in allergic airway inflammation. The effects of O3 inhalation and glucocorticoid treatment were studied in a mouse model of allergic asthma induced by sensitization and challenge with Aspergillus fumigatus (Af) in vivo. The role of O3 and glucocorticoids in regulation of SP-D expression was investigated in A549 and primary human type II alveolar epithelial cells in vitro. Budesonide inhibited airway hyperreactivity, eosinophil counts in the lung and bronchoalveolar lavage (BAL) and CCL11, IL-13, and IL-23p19 release in the BAL of mice sensitized and challenged with Af (p < 0.05). The inhibitory effects of budesonide were attenuated on inflammatory changes and were completely abolished on airway hyperreactivity after O3 exposure of mice sensitized and challenged with Af. O3 stimulated release of pro-neutrophilic mediators including CCL20 and IL-6 into the airways and impaired the inhibitory effects of budesonide on CCL11, IL-13 and IL-23. O3 also prevented budesonide-induced release of the immunoprotective lung collectin SP-D into the airways of allergen-challenged mice. O3 had a bi-phasic direct effect with early (<12 h) inhibition and late (>48 h) activation of SP-D mRNA (sftpd) in vitro. Dexamethasone and budesonide induced sftpd transcription and translation in human type II alveolar epithelial cells in a glucocorticoid receptor and STAT3 (an IL-6 responsive transcription factor) dependent manner. Our study indicates that O3 exposure counteracts the effects of budesonide on airway inflammation, airway hyperreactivity, and SP-D production. We speculate that impairment of SP-D expression may contribute to the acute O3-induced airway inflammation. Asthmatics exposed to high ambient O3 levels may become less responsive to glucocorticoid treatment during acute exacerbations
Back reaction, covariant anomaly and effective action
In the presence of back reaction, we first produce the one-loop corrections
for the event horizon and Hawking temperature of the Reissner-Nordstr\"om black
hole. Then, based on the covariant anomaly cancelation method and the effective
action technique, the modified expressions for the fluxes of gauge current and
energy momentum tensor, due to the effect of back reaction, are obtained. The
results are consistent with the Hawking fluxes of a (1+1)-dimensional blackbody
at the temperature with quantum corrections, thus confirming the robustness of
the covariant anomaly cancelation method and the effective action technique for
black holes with back reaction.Comment: 17 page
Numerically efficient formulation for time-domain electromagnetic-semiconductor co-simulation for Fast-Transient Systems
published_or_final_versio
- …