4,577 research outputs found
A Study on the Body Insulators for the Bushing for HTS Devices at Cryogenic Temperature
AbstractA bushing for high temperature superconducting devices (HTS bushing) is important because of applying high voltage to the cable or the winding of the transformer. It is cooled with liquid nitrogen (LN2) and is insulated with various insulators. For the development of the HTS bushing, it is necessary to know the fundamental characteristics of various insulators at cryogenic temperature.The electrical characteristics of the breakdown were studied under AC and impulse voltages. Also, the mechanical characteristics such as tensile strength in air and LN2 were studied. It was confirmed that GFRP is excellent not only electrical characteristics but also mechanical characteristics in LN2
Optical spectroscopy of gan microcavities with thicknesses controlled using a plasma etch-back
The effect of an etch-back step to control the cavity length within GaN-based microcavities formed between two dielectric Bragg mirrors was investigated using photoluminescence and reflectivity. The structures are fabricated using a combination of a laser lift-off technique to separate epitaxial III-N layers from their sapphire substrates and electron-beam evaporation to deposit silica/zirconia multilayer mirrors. The photoluminescence measurements reveal cavity modes from both etched and nonetched microcavities. Similar cavity finesses are measured for 2.0 and 0.8 mm GaN cavities fabricated from the same wafer, indicating that the etchback has had little effect on the microcavity quality. For InGaN quantum well samples the etchback is shown to allow controllable reduction of the cavity length. Two etch steps of 100 nm are demonstrated with an accuracy of approximately 5%. The etchback, achieved using inductively coupled plasma and wet chemical etching, allows removal of the low-quality GaN nucleation layer, control of the cavity length, and modification of the surface resulting from lift-off
Brane Fluctuation and anomalous muon magnetic moment
We study the effects of extra dimensions on the muon anomalous magnetic
moment with brane fluctuation. Since the coupling is naturally suppressed if
brane fluctuation is considered by exponential softening factor for heavier
states, the contribution from the whole Kaluza-Klein graviton tower is shown to
be finite. The recent BNL E821 result is accomodated with
dimensional gravitational scale, , in the range of
TeV (), and TeV () with the brane
tension parameter , in the range TeV.Comment: 8 pages, LaTeX, 2 eps Figures, references added, version to appear in
PL
Damping mechanism for the strongly renormalized -axis charge transport in high- cuprate superconductors
We analyze the -axis infrared reflectivity of
LaSrCuO single crystals. The plasma edge near 6 meV,
observed below , is due to Cooper-pair tunneling. This low value of the
plasma edge is consistent with the -axis plasma frequency () obtained
from LDA calculations ( eV) if we take into account that the
single-particle charge transport along the axis is strongly incoherent both
above and below . We find no evidence for a reduction of the -axis
scattering rate () below . Our investigation suggests
, which is exactly opposite to the clean limit.
VSGD.94.6.1Comment: 4 pages, figures on request. Revtex, version 2, Materials Science
Center Internal Report Number VSGD.94.6.
Changes in microarchitectural characteristics at the tibial epiphysis induced by collagen-induced rheumatoid arthritis over time
10.2147/CIA.S35202Clinical Interventions in Aging7373-38
Superior pre-osteoblast cell response of etched ultrafine-grained titanium with a controlled crystallographic orientation
Ultrafine-grained (UFG) Ti for improved mechanical performance as well as its surface modification enhancing biofunctions has attracted much attention in medical industries. Most of the studies on the surface etching of metallic biomaterials have focused on surface topography and wettability but not crystallographic orientation, i.e., texture, which influences the chemical as well as the physical properties. In this paper, the influences of texture and grain size on roughness, wettability, and pre-osteoblast cell response were investigated in vitro after HF etching treatment. The surface characteristics and cell behaviors of ultrafine, fine, and coarse-grained Ti were examined after the HF etching. The surface roughness during the etching treatment was significantly increased as the orientation angle from the basal pole was increased. The cell adhesion tendency of the rough surface was promoted. The UFG Ti substrate exhibited a higher texture energy state, rougher surface, enhanced hydrophilic wettability, and better cell adhesion and proliferation behaviors after etching than those of the coarse- and fine-grained Ti substrates. These results provide a new route for enhancing both mechanical and biological performances using etching after grain refinement of Ti. ? The Author(s) 2017.115Ysciescopu
Efficacy and tolerability of the Galanin Analog NAX 5055 in the multiple-hit rat model of symptomatic infantile spasms
Infantile spasms are seizures manifesting in infantile epileptic encephalopathies that are associated with poor epilepsy and cognitive outcomes. The current therapies are not always effective or are associated with serious side effects. Early cessation of spasms has been proposed to improve long-term outcomes. To identify new therapies for infantile spasms with rapid suppression of spasms, we are using the multiple-hit rat model of infantile spasms, which is a model of refractory infantile spasms. Here, we are testing the efficacy and tolerability of a single dose of the galanin receptor 1 preferring analog, NAX 5055, in the multiple-hit model of spasms. To induce the model, postnatal day 3 (PN3) male Sprague-Dawley rats underwent right intracerebral infusions of doxorubicin and lipopolysaccharide; p-chlorophenylalanine was then injected intraperitoneally (i.p.) at PN5. After the onset of spasms at PN4, 11-14 rats/group were injected i.p. with either NAX 5055 (0.5, 1, 2, or 4mg/kg) or vehicle. Video monitoring for spasms included a 1h pre-injection period, followed by 5h of recording post-injection, and two 2h sessions on PN5. The study was conducted in a randomized, blinded manner. Neurodevelopmental reflexes were assessed daily as well as at 2h after injection. Respiratory function, heart rate, pulse distension, oximetry and blood glucose were measured 4h after injection. The relative expression of GalR1 and GalR2 mRNA over β-actin in the cerebral cortex and hippocampus was determined with real time reverse transcription polymerase chain reaction. There was no acute effect of NAX 5055 on spasm frequency after the single dose of NAX 5055 (n=11-13 rats/group, following exclusions). Neurodevelopmental reflexes, vital signs, blood glucose measured 4h post-injection, and survival were not affected. A reduction in pulse and breath distention of unclear clinical significance was observed with the 7mg/kg NAX 5055 dose. GalR1 mRNA was present in the cerebral cortex and hippocampus of PN4 and adult rats. The hippocampal - but not the cortical - GalR1 mRNA expression was significantly lower in PN4 pups than in adults. GalR1 mRNA was also at least 20 times less abundant in the PN4 cortex than GalR2 mRNA. In conclusion, a single dose of NAX 5055 has no acute efficacy on spasms or toxicity in the multiple hit rat model of medically refractory infantile spasms. Our findings cannot exclude the possibility that repetitive NAX 5055 administration may show efficacy on spasms. The higher expression of GalR2 in the PN4 cortex suggests that GalR2-preferring analogs may be of interest to test for efficacy on spasms
Alteration patterns of trabecular bone microarchitectural characteristics induced by osteoarthritis over time
10.2147/CIA.S32513Clinical Interventions in Aging7303-31
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