The low-to-high confinement mode transition (L-H transition) is one of the key elements in achieving a self-sustained burning fusion reaction. Although there is no doubt that the mean and/or ...oscillating radial electric field plays a role in triggering and sustaining the edge transport barrier, the detailed underlying physics are yet to be unveiled. In this special topic paper, the remarkable progress achieved in recent years is reviewed for two different aspects: (i) the radial electric field driving procedure and (ii) the turbulent transport suppression mechanism. Experimental observations in different devices show possible conflicting natures for these phenomena, which cannot be resolved solely by conventional paradigms. New insights obtained by combining different model concepts successfully reconcile these conflicts.
•50 mm-diameter Sn-doped (001) β-Ga2O3 crystals were grown in the VB furnace with ambient air.•Dislocation densities was widely distributed across a wafer from 100 to 2000/cm2.•FWHM values was also ...widely distributed across a wafer from 10 to 50 arcsec.•A carrier density of 3.6 × 1018/cm3 were obtained from a 0.1 mol% Sn-doped crystal.•The obtained (001) n-type wafers might be useful for epitaxial growth substrate.
50 mm-diameter Sn-doped β-Ga2O3 crystals with growth orientation perpendicular to (001) plane were grown with the newly-developed resistance heating vertical Bridgeman furnace using platinum–rhodium alloy crucibles in ambient air. Weak low angle grain boundaries and several small grains were detected on the both-side mirror-polished 50 mm-diameter (001) wafer, using high resolution refraction x-ray topography. However, no imperfections were observed over the whole wafer area when using crossed polarizer analysis. Measured values of both the full width at half maximum and the dislocation densities were widely distributed in the wafer, ranging from 10 to 50 arcsec and 100 to 2000 /cm2 respectively with no distinctive correlations among them. The Sn-doped crystals with concentrations ranging from 5 × 1017 to 5 × 1018 atom/cm3 could be grown by Sn-doping in a range from 0.05 to 0.1 mol%, and (001) oriented, 50 mm-diameter n-type oxide semiconductor wafers with a carrier density of 3.6 × 1018 /cm3, a mobility of 60 cm2/Vsec and a resistivity of 0.03 Ω-cm, were obtained from a 0.1 mol% Sn-doped crystal.
To investigate the role of Piezo1 and Piezo2 in surgically induced osteoarthritis (OA) in mice.
Male conditional knockout (cKO) mice missing Piezo1 and Piezo2 in the joint using Gdf5-Cre transgenic ...mice were induced with post-traumatic OA by destabilization of the medial meniscus (DMM) of the right knee joint at 12 weeks of age. The severity of OA was histologically assessed at 24 weeks of age. OA-associated pain was evaluated by static weight bearing analysis. Additionally, articular chondrocytes isolated from cKO mice were exposed to fluid flow shear stress (FFSS) to evaluate the expression of OA-associated genes.
Mice with conditional deletion of Piezo1 and Piezo2 showed normal joint development with no overt histological changes in the knee joint at 12 weeks and 24 weeks. DMM surgery induced moderate to severe OA in both control and cKO mice (median OARSI score: control, 4.67; cKO, 4.23, P = 0.3082), although a few cKO mice showed milder OA. Pain assessment by static weight-bearing analysis suggested Piezo ablation in the joint has no beneficial effects on pain. FFSS increased the expression of OA-related genes both in control and cKO mice to similar extents.
Piezo1 and Piezo2 are not essential for normal joint development. Genetic ablation of Piezo channels did not confer evident protective effects on OA progression in mice. In vitro data suggests that different mechanotransducers other than Piezo channels mediate FFSS in mechanical stress-induced gene expression.
Probiotics have been used to treat gastrointestinal disorders. However, the effect of orally intubated probiotics on oral disease remains unclear. We assessed the potential of oral administration of ...Lactobacillus gasseri SBT2055 (LG2055) for Porphyromonas gingivalis infection. LG2055 treatment significantly reduced alveolar bone loss, detachment and disorganization of the periodontal ligament, and bacterial colonization by subsequent P. gingivalis challenge. Furthermore, the expression and secretion of TNF-α and IL-6 in gingival tissue was significantly decreased in LG2055-administered mice after bacterial infection. Conversely, mouse β-defensin-14 (mBD-14) mRNA and its peptide products were significantly increased in distant mucosal components as well as the intestinal tract to which LG2055 was introduced. Moreover, IL-1β and TNF-α production from THP-1 monocytes stimulated with P. gingivalis antigen was significantly reduced by the addition of human β-defensin-3. These results suggest that gastrically administered LG2055 can enhance immunoregulation followed by periodontitis prevention in oral mucosa via the gut immune system; i.e., the possibility of homing in innate immunity.
A resistance heating vertical Bridgeman (VB) furnace able to maintain high temperatures up to 1830 °C in ambient air was developed to suppress weight loss of both the crucible and raw material Ga2O3. ...Large-size 50 mm diameter β-Ga2O3 crystals with a growth orientation perpendicular to (1 0 0) plane were grown by the VB growth process in platinum-rhodium alloy crucibles using this furnace. The total weight loss during a VB growth run is very small, amounting to less than 1% of the total weight of the platinum-rhodium alloy crucible and the Ga2O3 raw material.
A new approach to β-Ga2O3 single crystal growth was studied, using the vertical Bridgman (VB) method in ambient air, while measuring the β-Ga2O3 melting temperature and investigating the effects of ...crucible composition and shape. β-Ga2O3 single crystals 25mm in diameter were grown in platinum–rhodium alloy crucibles in ambient air, with no adhesion of the crystals to the crucible wall. Single crystal growth without a crystal seed was realized by (100) faceted growth with a growth direction perpendicular to the (100) faceted plane.
•Single-crystal growth of β-Ga2O3 was studied by the vertical Bridgman (VB) method.•β-Ga2O3 crystals were grown in platinum–rhodium alloy crucibles in ambient air.•Single crystals with (100) faceted plane were grown without seeding.•Growth direction of the crystals grown was perpendicular to the (100) faceted plane.
A new type of self-sustained divertor oscillation is discovered in the Large Helical Device stellarator, where the peripheral plasma is detached from material diverters by means of externally applied ...perturbation fields. The divertor oscillation is found to be a self-regulation of an isolated magnetic field structure (the magnetic island) width induced by a drastic change in a poloidal inhomogeneity of the plasma radiation across the detachment-attachment transitions. A predator-prey model between the magnetic island width and a self-generated local plasma current (the bootstrap current) is introduced to describe the divertor oscillation, which successfully reproduces the experimental observations.
We derive a variety of exact black hole solutions in a subclass of Horndeski's scalar–tensor theory possessing shift symmetry,
$\phi \to \phi +c$
, and reflection symmetry,
$\phi \to -\phi $
. The ...theory admits two arbitrary functions of
$X:=-(\partial \phi)^2/2$
, and our solutions are constructed without specifying the concrete form of the two functions, implying that black hole solutions in specific scalar–tensor theories found in the literature can be extended to a more general class of theories with shift symmetry. Our solutions include a black hole in the presence of an effective cosmological constant, the Nariai spacetime, the Lifshitz black hole, and other nontrivial solutions, all of which exhibit nonconstant scalar-field profiles.
For solid-state spin qubits, single-gate rf readout can minimize the number of gates required for scale-up since the readout sensor can integrate into the existing gates used to manipulate the ...qubits. However, state-of-the-art topological error correction codes benefit from the ability to resolve the qubit state within a single shot, that is, without repeated measurements. Here, we demonstrate single-gate, single-shot readout of a singlet-triplet spin state in silicon, with an average readout fidelity of 82.9% at 3.3 kHz measurement bandwidth. We use this technique to measure a tripletT−to singletS0relaxation time of 0.62 ms in precision donor quantum dots in silicon. We also show that the use of rf readout does not impact the spin lifetimes (S0toT−decay remained approximately 2 ms at zero detuning). This establishes single-gate sensing as a viable readout method for spin qubits.
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