The excitation and stabilization of Alfvén eigenmodes and their impact on energetic ion confinement were investigated with negative ion based neutral beam injection at 330-360 keV into weak or reversed magnetic shear plasmas on JT-60U. Toroidicity induced Alfvén eigenmodes (TAEs) were observed in weak shear plasmas with ⟨βh⟩ ⩾ 0.1% and 0.4 ⩽ vb||/vA ⩽ 1. The stability of TAEs is consistent with predictions by the NOVA-K code. New burst modes and chirping modes were observed in the higher β regime of ⟨βh⟩ ⩾ 0.2%. The effect of TAEs, burst modes and chirping modes on fast ion confinement has been found to be small so far. It was found that a strongly reversed shear plasma with internal transport barrier suppresses AEs.
Results of fast particle experiments in JT-60U are presented. The fast particles were created with ICRF heating and negative ion based neutral beam injection (N-NBI) heating. With both heating systems Alfvén eigenmodes (AEs) were excited. The AEs that were excited with ICRF during sawtooth stabilization experiments are used to extract information about the magnetic safety profile in the plasma centre. These measurements are compared with motional Stark effect measurements and with sawtooth models. The first results on the radial mode structure of TAEs as measured with an X mode reflectometer system are also given. When the N-NBI beam was injected into a sawtoothing plasma, a significant increase in sawtooth period was observed. A survey is given of the bursting, chirping and stationary frequency modes that have been found in the Alfvén range of frequencies when N-NBI was injected. Most, but not all, of these modes scale with the Alfvén velocity. One group of modes that starts in the continuum and chirps up to the toroidicity induced Alfvén eigenmode (TAE) gap in typically 200 ms can be identified as resonant TAEs, whereas another group of modes appears as short bursts (up to 20 ms) in the Alfvén continuum.
Introduction: Warfarin and direct oral anticoagulants (DOACs) have been widely used in antithrombotic therapy. Although warfarin use has been suspected to be associated with osteoporosis risk, several studies have shown otherwise. Conversely, a few reports have found an association between DOACs and osteoporosis. This study therefore clarifies the association between oral anticoagulants and osteoporosis by analyzing real-world data using different methodologies, algorithms, and databases. Methods: Real-world data from the US Food and Drug Administration Adverse Event Reporting System (FAERS; 2004-2016) and Japanese administrative claims database (2005-2017; JMDC Inc., Tokyo) were used. Reporting odds ratio (ROR) and information component (IC) were calculated through disproportionality analysis (DPA) using reports recorded in the FAERS. Sequence symmetry analysis (SSA) was employed to calculate the adjusted sequence ratio (SR) using the JMDC Claims Database. For the adjusted SR and ROR, a significant signal was detected when the lower limit of the two-sided 95% confidence interval (CI) was more than 1. For the IC, a significant signal was detected when the lower limit of the 95% CI was more than 0. Results: DPA for warfarin found significant signals for osteoporosis in ROR (1.43, 95% CI: 1.32-1.54) and IC (0.50, 95% CI: 0.39-0.61). SSA showed a significant association between warfarin use and osteoporosis or bisphosphonate use. Moreover, a significant association was observed in males and females, albeit only for warfarin. Conclusion: Multi-methodological data mining revealed that warfarin use, not DOACs, is significantly associated with osteoporosis regardless of sex difference.
Thermus thermophilus HB8 expresses silica-induced protein (Sip) when cultured in medium containing supersaturated silicic acids. Using genomic information, Sip was identified as a Fe 3؉ -binding ABC transporter. Detection of a 1-kb hybridized band in Northern analysis revealed that sip transcription is monocistronic and that sip has its own terminator and promoter. The sequence of the sip promoter showed homology with that of the A -dependent promoter, which is known as a housekeeping promoter in HB8. Considering that sip is transcribed when supersaturated silicic acids are added, the existence of a repressor is presumed. DNA microarray analysis suggested that supersaturated silicic acids and iron deficiency affect Thermus cells similarly, and enhanced sip transcription was detected under both conditions. This suggested that sip transcription was initiated by iron deficiency and that the ferric uptake regulator (Fur) controlled the transcription. Three Fur gene homologues (TTHA0255, TTHA0344, and TTHA1292) have been annotated in the HB8 genome, and electrophoretic mobility shift assays revealed that the TTHA0344 product interacts with the sip promoter region. In medium containing supersaturated silicic acids, free Fe 3؉ levels were decreased due to Fe 3؉ immobilization on colloidal silica. This suggests that, because Fe 3؉ ions are captured by colloidal silica in geothermal water, Thermus cells are continuously exposed to the risk of iron deficiency. Considering that Sip is involved in iron acquisition, Sip production may be a strategy to survive under conditions of low iron availability in geothermal water. IMPORTANCEThe thermophilic bacterium Thermus thermophilus HB8 produces silica-induced protein (Sip) in the presence of supersaturated silicic acids. Sip has homology with iron-binding ABC transporter; however, the mechanism by which Sip expression is induced by silicic acids remains unexplained. We demonstrate that Sip captures iron and its transcription is regulated by the repressor ferric uptake regulator (Fur). This implies that Sip is expressed with iron deficiency. In addition, it is suggested that negatively charged colloidal silica in supersaturated solution absorbs Fe 3؉ ions and decreases iron availability. Considering that geothermal water contains ample silicic acids, it is suggested that thermophilic bacteria are always facing iron starvation. Sip production may be a strategy for surviving under conditions of low iron availability in geothermal water. S ilica (SiO 2 ) is one of the most abundant substances in the Earth's crust. In aqueous solution, silica dissolves as monosilicic acid, Si(OH) 4 , the solubility of which depends on conditions such as temperature, pH, and salt concentrations (1). In geothermal water at high temperature and pressure underground, silicic acids are in equilibrium with the quartz in rock layers, with concentrations reaching around 600 ppm at 300°C. When this geothermal water is discharged to the surface, where the solubility of amorphous silica is about 300 ppm...
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