1,174 research outputs found
Conduction of activity between muscles in the terminal region of the common bile duct and in the neighboring duodenum
The relationship between muscle activity at the terminal region of the common bile duct and the duodenal muscle was examined in rabbits. The rhythmic muscle activity in the terminal region was synchronous with duodenal muscle activity. The activity of the latter muscle preceded the former. The activity at the terminal region synchronous with the rhythmic activity of the duodenal muscle sometimes disappeared spontaneously. The muscle activity of the ampulla and the spincter at the terminal region was sometimes independently lost. The conduction of excitation from the duodenal muscle to the terminal region appeared to be performed at several sites. The existence of a "conduction-shunt path" between the terminal region and the duodenum, as well as between the ampulla and the sphincter appeared probably. Some quantitative differences were found between the spincter, ampulla and duodenum in inhibitory effects to stimulation of splanchnic nerves and reflex effects and to excitatory effects of cholecystokinin-pancreoxymin and caerulein. These results seem to indicate that the sympathetic nerves and the intramural cholinergic neurones controlling these region carry out activities quantitatively different from each other.</p
The Effect of Self-gravity of Gas on Gas Fueling in Barred Galaxies with a Supermassive Black Hole
In our previous paper, we have shown that a gas disk in the nuclear region of
a barred galaxy which contains a central supermassive black hole (SMBH) rapidly
evolves into a nuclear gas ring by the effect of an additional inner Lindblad
resonance caused by the SMBH. In this paper, we investigate the fate of the gas
ring, involving self-gravity of gas, using two-dimensional hydrodynamical
simulations. We find that the gas ring becomes gravitationally unstable for a
gas surface density of gas above a critical value, and fragments into several
gas clumps. Some denser clumps increase their mass via the accretion of the
surrounding gas and collisions with other clumps, and finally a very massive
gas clump (10^7 M_sun) is formed. Due to the torque from the most massive
clump, a part of the gas in the ring loses its angular momentum and falls into
the galactic center. As a result, a nuclear gas disk (50 pc) is formed around
the SMBH. The accretion rate for pc attains about 1 M_sun/yr for
3.5*10^7 yr. At the final phase of the bar-driven fueling, self-gravity is
crucial for the angular momentum transfer of the gas. This is a new mechanism
for gas fueling to the vicinity of the SMBH.Comment: 14 pages, 7 figures, AASTeX, submitted to Ap
Large time behavior and optimal decay estimate for solutions to the generalized Kadomtsev--Petviashvili--Burgers equation in 2D
We consider the Cauchy problem for the generalized
Kadomtsev--Petviashvili--Burgers equation in 2D. This is one of the nonlinear
dispersive-dissipative type equations, which has a spatial anisotropic
dissipative term. Under some suitable regularity assumptions on the initial
data , especially the condition , it is known that the solution to this problem decays at
the rate of in the -sense. In this paper, we
investigate the more detailed large time behavior of the solution and construct
the approximate formula for the solution at . Moreover, we obtain
a lower bound of the -norm of the solution and prove that the decay
rate of the solution given in the previous work to be
optimal.Comment: 23 page
Sedimentary environments of mangrove swamp in the Funaura Bay, Iriomote Island, Okinawa Prefecture, Southwest Japan
The distribution of conch shell contained in clastic sediments in the mangrove swamps in the Funaura Bay, Iriomote Island, Okinawa Prefecture was studied. The sediments in the mangrove swamp are mainly composed of up to 90% sands. The sand clasts are inferred to be derived from the sandstone of Miocene Yaeyama Group. The conch shells are richer in the muddy fraction than the sandy fraction. Many Terebralia palustris inhabit the mangrove swamp. However few dead shells were also observed in the sediments. Effect of selective transportation hermit crabs is considered to be the cause of this distribution
Electronic Videoendoscopy of Laryngeal Lesions Using a New Type of Rhinolarynx Endoscope Portion
Patients with laryngeal lesions were observed and the lesions were recorded with an
electronic videoendoscope system using the PENTAX EPM-3300 video processor and the
PENTAX VNL-1330 endoscope portion. The electronic videoendoscope system differs
from the conventional fiberoptic endoscope connected to a video camera in that a small
monochrome charge-coupled device (CCD) chip is built in the tip of the endoscope portion.
The PENTAX VNL-1330 rhinolarynx endoscope portion has a tip and insertion tube of
approximately 4mm in outer diameter to allow its introduction through the nasal passages
into the larynx. The dynamic color images provided by this system were superior to those
obtained by a conventional rhinolarynx flexible fiberscope connected to a video camera in
both quality and resolution of detail. This system should be useful in diagnosing laryngeal
lesions
The Effect of a Central Supermassive black hole on the Gas Fuelling
When a supermassive black hole exists in the centre of a galaxy, an
additional inner Lindblad resonance (ILR) exists inside the usual ILRs. We
study gas dynamics in a weakly barred potential with a central supermassive
black hole by using 2D numerical simulations, and we investigate the effect of
the additional ILR on fuelling gas into nuclear starburst regions or AGNs. Our
numerical results show that strong trailing spiral shocks are formed at the
resonance region, and the gas in the shock region is rapidly fuelled into a
central region and make a nuclear gas ring. As a result, a large amount of gas
is concentrated in the nuclear region beyond the ILR in a dynamical time scale.Comment: 7 pages, 14 Postscript figures, LaTeX 2.09, requires mn.sty, to be
published in MNRA
Clinical Experience With a New Type of Rhino-Larynx Electronic Endoscope PENTAX VNL-1530
We observed recordings of pictures obtained from patients with diseases of the larynx by using a new type of rhino-larynx electronic endoscope, PENTAXVNL-1530 connected to a video processor, PENTAX
EPM-3300 (Asahi Optical Co., Ltd.). The electronic endoscope differs from the fiberoptic endoscope
in that it contains a small light-sensitive charge coupled device (CCD) chip that is attached
to the tip of the endoscope. This electronic endoscope has the smallest CCD camera of 5.1 mm in diameter,
in the tip portion, and can be passed through the nasal passage into the laryngeal cavity. The
dynamic image provided by this system is superior to that obtained by a flexible laryngofiberscope
in resolution of the detail
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