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AC loss is a critical issue for high-temperature superconducting (HTS) applications. Earlier studies have focused on ac loss in HTS conductors carrying sinusoidal currents. However, HTS conductors in some applications carry non-sinusoidal currents, and hence it is essential to study ac loss under those conditions. This study presents simulated ac loss of a REBCO stack and coil winding carrying currents with square, trapezoidal, and triangular waveforms. The simulation method is based on the T-A formulation implemented in COMSOL Multiphysics 6.0. AC loss dependence on frequency and n-value is also investigated. The simulation results show ac loss varies with current waveforms for both the stack and coil winding—loss magnitude is largest under square waveform, followed by trapezoidal, sinusoidal, and triangular waveform. Surprisingly, ac loss of the stack decreases with increasing frequency as f−2/n, while f−1/n for the coil winding. The difference between the ac loss values in the stack and coil winding under different current waveforms becomes smaller with increasing n-value. With an infinitely large n-value, the difference in the ac loss values for all different waveforms may disappear, as the critical state model suggests.

The purpose of the present study was to assess the prevalence of various types of malocclusions in a group of female patients with adolescent idiopathic scoliosis (AIS), as well as the association between occlusal anomalies and the side, location, and severity of the spine deformity. The study group was comprised of 60 females aged 12–16 years with AIS and 54 healthy controls. Apart from clinical examination, alginate impressions and wax bites were taken. Occlusal traits were assessed on the casts in maximum intercuspation. Data were statistically analyzed with a significance taken as p < 0.05. All patients with AIS showed at least one abnormal orthodontic trait, while 9 (16.7%) patients from the control group had dentition free from any orthodontic anomaly. The difference was statistically significant (p = 0.0032). In the sagittal dimension, patients with AIS had a higher frequency of bilateral distocclusion and unilateral mesiocclusion as compared to the control group (p = 0.0004 and p = 0.0034, respectively). They also showed crowding, increased overjet and overbite more often than healthy age- mates (p = 0.0417, p = 0.0121, and p = 0.0166, respectively). Regarding the association between site, side, or severity of scoliosis and the occurrence of the malocclusion, asymmetric molar occlusion was more frequently observed in patients with right convex (p = 0.0149), while unilateral mesiocclusion, appeared more often in patients with the thoracic apex of the curve (p = 0.0349). The results emphasize a need for collaboration between orthopedists and orthodontists in the complex medical care for scoliotic individuals. Orthodontic treatment can alleviate negative impact that a malocclusion has on the oral health, aesthetics, and psychological well-being of this vulnerable group of patients.