Objective To investigate the effect of repetitive magnetic stimulation (rMS) of the spinal cord on limb angiogenesis in healthy rats and explore its implication for the treatment of lymphedema. Method Twelve adult male Sprague-Dawley rats were divided into four groups as follows: sham rMS followed by tissue harvest 5 minutes later (group 1, n=2), 1 Hz rMS and tissue harvest 5 minutes later (group 2, n=3), 20 Hz rMS and tissue harvest 5 minutes later (group 3, n=3), 20 Hz rMS and tissue harvest 30 minutes later (group 4, n=4). Animals were treated with 20-minute rMS with 120% of the motor threshold on their left side of upper lumbar spinal cord. Expression of angiogenic factors, that is, Akt, phospho-Akt (pAkt), endothelial nitric oxide synthase (eNOS), phospho-eNOS (p-eNOS) were measured by western blot. Bilateral hindlimb muscles (quadriceps and gastrocnemius) were harvested. Results Expression of Akt in left quadriceps increased in group 4 compared with group 2 and 3 (3.4 and 5.3-fold each, p=0.026). Expression of eNOS in left plus right quadriceps markedly increased in group 3 and 4 compared with group 1 and 2 (p=0.007). Expressions of eNOS, Akt and p-eNOS, pAkt in gastrocnemius were not comparable between four groups (p>0.05). Conclusion Repetitive magnetic stimulation of the spinal cord may exert an angiogenic effect closely linked to lymphangiogenesis. It has clinical implication for the possible therapy of lymphedema caused by breast, cervical or endometrial cancer operation. Future studies with the specific lymphatic endothelial cell markers are required to confirm the effect of rMS on lymphangiogenesis.

In electric vehicle (EV) charging applications, maintaining high efficiency over a wide output voltage range is considered the most challenging mission. Pulse width modulation (PWM) controlled resonant converter can be a nice candidate, because its output voltage boosting capability is independent to the resonant tank components. However, it reveals its limitation showing efficiency drop between two resonant points. This paper proposes a resonant converter with "sequential PWM" achieving multiple resonant points while doubling the output voltage. The proposed converter significantly reduces turnoff loss and maximum resonant current by having multiple resonant points while doubling the output voltage. Accordingly, proposed converter maintains competitive high efficiency over a wide output voltage range.INDEX TERMS EV charger, resonant converter, wide voltage range 0

No abstract