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We propose a new dynamic flow imaging using 320-detector row CT, and investigate the assessment of coronary flow in aneurysms of Kawasaki disease in adulthood.
Six patients with Kawasaki disease and coronary aneurysms associated (26.7 years old) and six controls were enrolled. Dynamic coronary CT angiography with 320-row CT was continuously performed at mid-diastole throughout 15–25 cardiac cycles with prospective Electrocardiogram gating after injection of contrast media. Dynamic data sets of 15–25 cycles were computed into 90–100 data sets by motion coherence image processing. Next, time–density curves for coronary arteries were calculated for all the phases. On the basis of the maximum slope method, coronary flow index was defined as the ratio of the maximum upslope of the attenuation of coronary arteries to the upslope of the attenuation of ascending aorta on the time–density curves. Coronary flow indexes for the proximal and distal sites of coronary arteries and intra-aneurysm were measured.
Sexual dimorphism is thought to have evolved via selection on both sexes. Ostracodes display sexual shape dimorphism in adult valves; however, no previous studies have addressed temporal changes on evolutionary timescales or examined the relationships between sexual shape dimorphism and selection pressure and between sexual shape dimorphism and juvenile shape. Temporal changes in sexually dimorphic traits result from responses of these traits to selection pressure. Using the Gaussian mixture model for the height/length ratio, a valve-shape parameter, we identified sexual differences in the valve shape of Krithe dolichodeira s.l. from deep-sea sediments of the Paleocene (62.6–57.6 Ma) and estimated the proportion of females in the fossil populations at 11 time intervals. Because the proportion of females in a population is altered by the mortality rate of adult males, it is reflective of selection pressure on males. We attempted to correlate the height/length ratios between the sexes with the proportion of females, taking into consideration that the valve shape was not linked with the selection pressure on males. In time-series data of the height/length ratio, both sexes indicate no significant changes on evolutionary timescales, even though the sex ratio of the population changed from female skewed to male skewed during the late Paleocene. The sexual shape dimorphism was not driven by sexual selection. The static allometry between the height/length ratio and length indicates that the sexual shape dimorphism did not function for sexual display. The absence of change over time in the female allometric slope suggests that the evolution of valve shape was constrained by stasis.
We developed a new GaN on SiC growth method by metalorganic vapour phase epitaxy (MOVPE) using of a single 2-dimension-growth step. Prior to epitaxy, to inhibit pre-reaction of Si-face SiC substrate with TMGa and NH3, TMAl was flowed without NH3. 1.5 μm of undoped crack-free GaN was grown on 6H-SiC (Si-face). Without buffer layer, the vertical resistance of GaN/SiC structure was found to be around 82.1Ω as determined by I-V characteristic. Further reduction in vertical resistance is expected by growth of n-GaN (1.5μm)/SiC structure (300μm). We also expect a SiC-based GaN heterostructure vertical FET will achieve high power and high switching speed performance.
We investigated the effect of the chemical etching on light-emitting porous silicon. It is well known that the treatment with the mixture of HF acid and ethanol noticeably enhances photoluminescent efficiency but the mechanism is not clarified yet. We found that ethanol plays a key role to oxidize silicon hydride species that dissolves with the aid of HF acid. In addition, the chemical treatment with methanol or propanol instead of ethanol gave the same result.
Thermodynamic calculations of the reaction between hydrated OPC phases and saline groundwater indicate an elevated pH > 13, which is not associated with the well known initial release of the alkalis. Instead, the pH elevation is attributed to the generation of OH− accompanied with the precipitation of Friedel's salt (Ca3Al2O6·CaCl2·10H2O; AFm-Cl2) from the reaction of portlandite (Ca(OH)2;CH) and hydrogarnet (Ca3Al2O6·6H2O; C3AH6) with chloride ions from the saline groundwater. If such a reaction mechanism were to occur in the context of the geological disposal of radioactive wastes, the impact of a hyper alkaline plume on other barrier components, such as a bentonite buffer, could be significant. Experimental investigations were therefore conducted using only portlandite and hydrogarnet to represent hydrated OPC and NaCl solution to represent a saline groundwater. The pH elevation was confirmed and showed good agreement with the thermodynamic calculations. The experiments were repeated using hardened OPC paste to confirm this reaction mechanism in the presence of other hydrated OPC phases. In this case, however, the pH elevation was not as high as expected. This deviation can be explained by the residual aluminum, after being partially consumed by AFt and/or AFm, not being wholly assigned to hydrogarnet and a better agreement between the thermodynamic calculations and the experimentally measured results can be made assuming a fraction of aluminum is incorporated into the C-S-H gel phase.
Effects of an implosion nonuniformity with [ell ] = 1 ([ell ]:
Legendre polynomial mode number) on the hot spark formation
were investigated in a series of direct-drive implosion experiments
at the Gekko-Xll glass laser (Yamanaka et al., 1987).
The implosion dynamics and the performance from the early to
final stage of the implosion were observed with a variety of
X-ray imaging and neutron diagnostics. A drive nonuniformity
in the implosion with [ell ] = 1 was observed in the shape of
the accelerated target at the early stage of the implosion.
At the final stage of the implosion, the resultant nonuniformity
with [ell ] = 1 was also observed as a geometrical shift of core
plasmas from the center of the chamber. The observed neutron
yield and X-ray emission properties at the final stage of the
implosion were significantly degraded with an increase of the
implosion nonuniformity with [ell ] = 1. The experimental results
were compared with one-dimensional (1-D) and two-dimensional
(2-D) hydrodynamic simulations. As a result, it was found that
the implosion nonuniformity with [ell ] = 1 shifts the whole
implosion dynamics towards its direction and prevents the
confinement of the gas fuel considerably. However, the
experimentally observed degradation in the hot spark formation,
such as reductions in neutron yield and features in X-ray emission,
can be reproduced in 2-D simulations not with an asymmetric
perturbation of [ell ] = 1 only but with multimode nonuniformities
such as [ell ] = 1 coupled with some additional middle-mode ones
(e.g., [ell ] = 6). Such a complex spike structure caused by
the multimode nonuniformities was found to be essential for
the experimentally observed rapid cooling of the hot spark.
Forty-seven mucocoeles of the ethmoid and/or sphenoid sinuses (33 males, 14 females) were operated on during the 10-years period from 1980 through 1989. Thirty-seven cases were post-operative mucocoele, while the remaining 10 were so-called primary mucocoeles. None of the cases had a history of facial trauma. In the majority of post-operative cases, the mucocoele develops 15–24 years after initial surgery. Paranasal sinus surgery in young patients (teenagers) may lead to a mucocoele due to post-operative scarring in the surgical wound. The principal symptoms include globe displacement, double vision, headache, deep orbital pain, a mass in the supero-medial quadrant of the orbit, visual disturbance, etc. Sufficient opening of the mucocoele wall by the endonasal approach is recommended for surgical treatment of ethmoidal and sphenoidal mucocoeles
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