Polarization-insensitive phase-modulated metasurface using single thermally stimulated vanadium dioxide chip.

Considering that typically more than two pin diodes or other tunable elements are required in the unit cell of polarization-insensitive reconfigurable metasurfaces (RMs), this paper proposes a new approach to design a polarization-insensitive RM unit using only one VO2 chip. A polarization-insensitive phase-modulated metasurface (PMM) using single VO2 chip is presented. The surface layer is composed of an outer ring and an inner cross, with a VO2 chip loaded at the connection of the cross. As the VO2 chip can be connected with the metal patch on all sides, only one VO2 chip is used in this polarization-insensitive design. By thermally controlling VO2 chips switch between low-resistance and high-resistance states, the PMM achieves a 1-bit phase shift within 180° ± 37° from 7.85 to 15 GHz. A prototype is fabricated and measured, and the measured results have verified the correction of the design and analysis of the designed PMM.

[Clinical observation on deep-oblique acupuncture with long needle at Guanyuan (CV 4) for urinary retention].

OBJECTIVE: To observe differences of clinical therapeutic effects between deep-oblique acupuncture with long needle and regular perpendicular acupuncture at Guanyuan (CV 4) for urinary retention to explore standard acupuncture method in clinic. METHODS: One hundred and thirty-two cases of urinary retention were randomly divided into an observation group (78 cases) and a control group (54 cases). Needles with 75 mm in length were deeply and obliquely inserted into Guanyuan (CV 4) in the observation group while needles with 40 mm in length were perpendicularly inserted. Clinical therapeutic effects in two groups were observed. RESULTS: After treatment the total effective rate was 80.8% (63/78) in the observation group and 57.4% (31/54) in the control group, which had significant difference between two groups (P<0.05). The curative effect of postpartum retention of urine was obviously superior to that of postoperative and prostate-induced urinary retention in the ebservation group, and the effect of urinary retention due to different etiology in the observation was also superior to that in the control group in the ebservation group [in the observation group total effective rate was 88.6% (47/53) in postpartum retention of urine, 50.0% (3/6) in prostate-induced urinary retention and 68.4% (13/19) in orthopedic postoperative retention of urine while in the control group total effective rate was 69.4% (25/36) in postpartum retention of urine, 20.0% (1/5) in prostate-induced urinary retention and 38.5% (5/13) in orthopedic postoperative retention of urine)]. CONCLUSION: The deep-oblique acupuncture with long needle at Guanyuan (CV 4) has significant curative effect on urinary retention in clinic, especially for patients with postpartum urinary retention, which could be taken as standard acupuncture method.