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Further investigation of fast ion effects on turbulence and transport in the fast ion regulated enhancement (FIRE) mode discharge (Han et al 2022 Nature 609 269–275) was performed in this work as a continuation of a previous study (Kim et al 2023 Nucl. Fusion 63 124001) that showed that the dominant turbulence suppression mechanism by fast ions is the dilution effect in the FIRE mode discharge. The current study includes (i) the impact of the fast ion relevant mode observed in the simulation of thermal energy flux, (ii) dilution effects by fast ions compared to dilution effects by other species, and (iii) fast ion effects on electron-scale turbulence. First, nonlinear gyrokinetic simulation results show that turbulence is significantly suppressed even without the fast ion relevant mode, indicating that the impact of this mode on thermal transport is not significant in this discharge. Second, further analysis on the dilution effects shows the three following results: Turbulence is not completely suppressed by the reduced main ion density fraction effect due to impurities; the reduction in energy flux can be limited by a certain impurity mode that is destabilized by a high impurity density gradient from adjusting the main ion density gradient; electrons can contribute to turbulence suppression through the main ion density gradient change, although this effect is less significant compared to other species. Third, we observe that two fast ion effects can influence the linear growth rate of the electron-scale turbulence mode. The growth rate decreases by an increase in ${\beta _*}\left( { \equiv \left( { - 8\pi /{B^2}} \right){\text{d}}p/{\text{d}}r} \right)$ and increases by dilution effects, suggesting that fast ion effects on electron-scale turbulence can differ depending on the operation scenario, such as the fast ion fraction. The comprehensive analysis performed in this study can enhance our understanding of fast ion physics, required for burning plasma operation in the future.

“Genome-based precision feeding” is a concept that involves the application of customised diets to different genetic groups of cattle. We investigated the effects of the genomic estimated breeding value (gEBV) and dietary energy to protein ratio (DEP) on growth performance, carcass traits, and lipogenic gene expression in Hanwoo (Korean cattle) steers. Forty-four Hanwoo steers (BW = 636 kg, age = 26.9 months) were genotyped using the Illumina Bovine 50 K BeadChip. The gEBV was calculated using genomic best linear unbiased prediction. Animals were separated into high gEBV of marbling score or low-gMS groups based on the upper and lower 50% groupings of the reference population, respectively. Animals were assigned to one of four groups in a 2 × 2 factorial arrangement: high gMS/high DEP (0.084 MJ/g), high gMS/low DEP (0.079 MJ/g), low gMS/high DEP, and low gMS/low DEP. Steers were fed concentrate with a high or low DEP for 31 weeks. The BW tended to be higher (0.05

We report experimental observations on the effect of plasma boundary shaping towards balanced double-null (DN) configuration on the plasma performance in KSTAR. The transition from a single-null to a DN configuration resulted in improved plasma performance, manifested through changes in the pedestal region, decreased density, and core MHD activity variation. Specifically, the DN transition led to a wider and higher pedestal structure, accompanied by grassy edge-localized modes (ELMs) characteristics. The density decrease was a prerequisite for performance enhancement during DN shaping, increasing fast ion confinement. Optimizing the plasma near the core region was associated with the suppression of sawtooth instabilities and the occurrence of fishbone modes during the DN transition. Integrated modeling demonstrated that secondary effects of the DN shaping could increase core thermal energy confinement.

This letter provides a new physical insight into the fast ion effects on turbulence in plasmas having a high fast ion fraction and peaked fast ion density profile. We elucidate turbulence stabilization mechanisms by fast ions that result in internal transport barrier formation in the fast ion regulated enhancement mode plasma. Both linear and nonlinear gyrokinetic simulations show that the dominant turbulence suppression mechanisms are the dilution effects. In particular, we find that turbulence can be sufficiently suppressed solely by an inverted main ion density gradient due to fast ions, for the first time. New physical findings reported here improve our understanding of fast ion effects on turbulence, essential for fusion energy production where . Moreover, they will open up a new methodology to control plasma turbulence applicable to a wide range of plasma confinement regimes.

This paper deals with one of the origins and trigger mechanisms responsible for the observed performance enhancements in the hybrid scenario experiments conducted in Korea Superconducting Tokamak Advanced Research (KSTAR). The major contribution to the performance improvement comes from a broader and higher pedestal formation. The increase of fast ion pressure due to a plasma density decrease also contributes substantially to the global beta. Although the reduced core plasma volume resulting from the pedestal expansion has a negative effect on the core thermal energy, a considerable confinement improvement observed in the inner core region limits the degradation. The one significant characteristic of high-performance discharges is the presence of Coherent Edge-localized Mode (CEM) activity. CEM is triggered during the pedestal recovery phase between typical ELM crashes and has been found to be related to the increase of particle and heat transport. It appears to underlie two commonly observed phenomena in high-performance hybrid scenario discharges in KSTAR; pedestal broadening and continuous density decrease. Despite the associated transport increase, CEM activities can induce performance enhancement. With the pedestal broadening, ELM crashes become delayed and weakened, which, in turn, allows for a higher pedestal. Moreover, the density decrease directly increases fast ion pressure by extending the beam-slowing-down time. The linear gyrokinetic analysis reveals that the increase of fast ions could initiate positive feedback loops, leading to the stabilization of Ion Temperature Gradient mode in the inner core region.

In this study, the electromagnetic characteristics of the insulated (INS), non-insulated (NI), and metal-clad (MC) racetrack coils are examined in a time-varying magnetic field. The delay in the generation of induced current and the amount of induced current when the coils are exposed to the time-varying magnetic field have been thoroughly examined. Additionally, the electromagnetic stability of each test coil was investigated under an overcurrent condition in the presence of an external magnetic ripple field. We also performed an AC loss test to investigate the effects of an MC layer on the magnitude of the AC loss. Based on the test results, the feasibility of using an MC winding technique for developing a highly stable high-temperature superconducting wind turbine generator with an enhanced electromagnetic response was thoroughly examined

A one-year-old, 2.6 kg, spayed female Maltese dog was referred with passage of faeces coming from the vulva, repeated vaginal discharge and vaginitis. Through physical examination, contrast radiograph and vaginoscopic exploration, the dog was diagnosed with rectovaginal fistula which was surgically corrected. After midline perineal incision, the rectovaginal fistula was isolated and transected. The vaginal and rectal defects were closed separately, but dehiscence of the surgical region took place three days after surgery. For the second operation, the rectal segment containing the fistula was removed by transanal rectal pull-through, and anastomosis was performed. Total follow-up time was 10 months and no sign of recurrence was reported. Early postoperative complications included perineal soiling and wound dehiscence, but the long-term outcome was good. This case is the first report of surgical correction of a rectovaginal fistula in a dog with a normal anus.

The objective of this study was to evaluate the in vitro efficacy of a topical skin cream containing a mixture of emu oil, jojoba oil, avocado oil, and tea tree oil against the canine skin pathogens Staphylococcus pseudintermedius and Malassezia pachydermatis. Three S. pseudintermedius isolates from dogs and a type strain of M. pachydermatis were used. Based on the standards of the Clinical and Laboratory Standards Institute, the minimal inhibitory concentration (MIC) and the minimal bactericidal/fungicidal concentration (MBC/MFC) were determined. In addition, microbial inactivation time was determined for both pathogens. The MICs against S. pseudintermedius and M. pachydermatis were 0.23% and 0.63%, while the MBC/MFCs were 7.5% and 5%, respectively. In assessments of the microbial inactivation time, after 12 h of incubation with the cream, the growth of both pathogens was completely inhibited. These results suggest that the skin cream tested here can be used as a substitute for generally used antibiotic/antifungal agents.

An eleven-year-old, 3-kg, intact female Maltese was presented for depression, anorexia and dyspnoea. Thoracic radiographs showed right-side pleural effusion, a vesicular emphysema pattern and consolidation of the right middle lung lobe. A presumptive diagnosis of lung lobe torsion (LLT) in the right middle lobe was made using a computed tomography scan. Thoracoscopic exploration was performed without one-lung ventilation in the right hemithorax. Pleural fluid and engorgement of the torsed lung lobe were observed. A total lung lobectomy of the right middle lung lobe was performed with a thoracoscopic-assisted procedure using hem-o-lok clips applied to the hilus. The dog was discharged three days after surgery, and no recurrence of the clinical signs of disease related to the respiratory system was observed during the follow-up time period of six months. Based on these findings, we conclude that thoracoscopic-assisted lung lobectomy using hem-o-lok clips is a minimally invasive surgical alternative to thoracotomy and successful operative intervention for lung lesions in small breed dogs.

Spectroscopic ellipsometry is used to characterize four different microcrystalline silicon films, which were fabricated by crystallizing a-Si: H films predeposited on glass substrates using solid phase crystallization. The dielectric function of silicon microcrystallites showed systematic broadening and shrinking of the peak features corresponding to the E1 and E2 critical points.