199 research outputs found
Crystalline chiral condensates off the tricritical point in a generalized Ginzburg-Landau approach
We present an extensive study on inhomogeneous chiral condensates in QCD at
finite density in the chiral limit using a generalized Ginzburg-Landau (GL)
approach. Performing analyses on higher harmonics of one-dimensionally (1D)
modulated condensates, we numerically confirm the previous claim that the
solitonic chiral condensate characterized by Jacobi's elliptic function is the
most favorable structure in 1D modulations. We then investigate the possibility
of realization of several multidimensional modulations within the same
framework. We also study the phase structure far away from the tricritical
point by extending the GL functional expanded up to the eighth order in the
order parameter and its spatial derivative. On the same basis, we explore a new
regime in the extended GL parameter space and find that the Lifshitz point is
the point where five critical lines meet at once. In particular, the existence
of an intriguing triple point is demonstrated, and its trajectory consists of
one of those critical lines.Comment: 17 pages, 20 eps figures; (v2) corrected an error in computation of
eighth order coefficients; (v3) typos corrected, version to appear in Phys.
Rev.
Scalar field perturbation on six-dimensional ultra-spinning black holes
We have studied the scalar field perturbations on six-dimensional
ultra-spinning black holes. We have numerically calculated the quasinormal
modes of rotating black holes. Our results suggest that such perturbations are
stable.Comment: 8 pages, 6 figures; v2:typo corrected; v3:ref. corrected; v4:revise
Thick Domain Walls Intersecting a Black Hole
We discuss the gravitationally interacting system of a thick domain wall and
a black hole. We numerically solve the scalar field equation in the
Schwarzschild spacetime and show that there exist scalar field configurations
representing thick domain walls intersecting the black hole.Comment: 14 pages, 8 figure
Development of Flat Tube Heat Exchanger for Heat Pump Air Conditoner
We developed a new type of a heat pump outdoor unit using an aluminum flat tube heat exchanger in order to improve the energy saving capability of an air conditioner. There are several difficulties in keeping a desired drainage performance, frost formation performance, as well as even distribution of refrigerant, when applying the flat tube heat exchanger to heat pump outdoor units. In order to achieve the same drainage performance and the frost formation performance as those of conventional heat exchangers, we have adopted new plate fins with ellipse cutouts. Flat tubes were inserted in the ellipse cutouts, and the slit position on a plate fin was properly adjusted. In order to achieve the even distribution of refrigerant, an aluminum distributor and 3-way pipes were installed to the evaporator. In this report, first we describe features of the flat tube heat exchanger. Next, we present and explain experimental results of the air-side heat transfer coefficient and the air-side pressure drop on the condition of dry, wet, and frost state respectively. Moreover, we present experimental results of the total heat transfer performance, including the refrigerant performance, under the conditions of the condensation and the evaporation. Finally, we explain the heat transfer performance and the effect of the flat tube heat exchanger to a conventional one in the case that the developed heat exchanger was mounted in heat pump outdoor unit
Gastric Mucosal Changes Caused by Lugol's Iodine Solution Spray: Endoscopic Features of 64 Cases on Screening Esophagogastroduodenoscopy
Aim. To clarify the endoscopic mucosal change of the stomach caused by Lugol's iodine solution spray on screening esophagogastroduodenoscopy (EGD).
Methods. Sixty-four consecutive patients who underwent EGD for esophageal squamous cell
carcinoma screening were included in this study. The records for these patients included gastric
mucosa findings before and after Lugol's iodine solution was sprayed. The endoscopic findings of
the greater curvature of the gastric body were retrospectively analyzed based on the following
findings: fold thickening, exudates, ulcers, and hemorrhage. Results. Mucosal changes occurred after Lugol's solution spray totally in 51 patients (80%). Fold thickening was observed in all 51 patients (80%), and a reticular pattern of white lines was found on the surface of the thickened gastric folds found in 28 of the patients (44%). Exudates were observed in 6 patients (9%). Conclusion. The gastric mucosa could be affected by Lugol's iodine; the most frequent endoscopic finding of this effect is gastric fold thickening, which should not be misdiagnosed as a severe gastric disease
Effect of Visuospatial Attention on the Sensorimotor Gating System
The integration of multiple sensory modalities allows us to adapt to the environment of the outside world. It is widely known that visual stimuli interfere with the processing of auditory information, which is involved in the ability to pay attention. Additionally, visuospatial attention has the characteristic of laterality. It is unclear whether this laterality of visuospatial attention affects the processing of auditory stimuli. The sensorimotor gating system is a neurological process, which filters out unnecessary stimuli from environmental stimuli in the brain. Prepulse inhibition (PPI) is an operational measure of the sensorimotor gating system, which a weaker prestimulus (prepulse), such as a visual stimulus, inhibits the startle reflex elicited by a subsequent robust startling stimulus (pulse) such as a tone. Therefore, we investigated whether the visual stimulus from the left or right visual space affects the sensorimotor gating system in a “rest” task (low attentional condition) and a “selective attention” task (high attentional condition). In the selective attention task, we found that the target prepulse presented in the left and bilateral visual fields suppressed the startle reflex more than that presented in the right visual field. By contrast, there was no laterality of PPI in the no-target prepulse condition, and there was no laterality of PPI in the rest task. These results suggest that the laterality of visuospatial attention affects the sensorimotor gating system depending on the attentional condition. Moreover, the process of visual information processing may differ between the left and right brain
Instability of a membrane intersecting a black hole
The stability of a Nambu-Goto membrane at the equatorial plane of the
Reissner-Nordstr{\o}m-de Sitter spacetime is studied. The covariant
perturbation formalism is applied to study the behavior of the perturbation of
the membrane. The perturbation equation is solved numerically. It is shown that
a membrane intersecting a charged black hole, including extremely charged one,
is unstable and that the positive cosmological constant strengthens the
instability.Comment: 12 pages, 3 figures, to be published in Physical Review
A boundary value problem for the five-dimensional stationary rotating black holes
We study the boundary value problem for the stationary rotating black hole
solutions to the five-dimensional vacuum Einstein equation. Assuming the two
commuting rotational symmetry and the sphericity of the horizon topology, we
show that the black hole is uniquely characterized by the mass, and a pair of
the angular momenta.Comment: 16 pages, no figure
Thick domain walls around a black hole
We discuss the gravitationally interacting system of a thick domain wall and
a black hole. We numerically solve the scalar field equation in the
Schwarzschild spacetime and obtain a sequence of static axi-symmetric solutions
representing thick domain walls. We find that, for the walls near the horizon,
the Nambu--Goto approximation is no longer valid.Comment: 18 pages, 11 figures, one reference adde
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