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Background: This study evaluated the radiological and clinical outcomes of bone grafts using fourth and fifth extensor compartmental arteries (4+5 ECAs) for the treatment of Kienböck's disease. Materials and Methods: In total, 21 patients (12 men and 9 women; mean age, 41 years; range, 19–59 years) were followed for a mean of 33 months. Radiological images were analyzed for the Lichtman stage, carpal height ratio, radioscaphoid angle, and Stahl's index. Clinical evaluation included range of motion, visual analog scale (VAS) score, grip strength, modified Mayo wrist score (MMWS), Lichtman outcome score, and Disabilities of the Arm, Shoulder and Hand (DASH) score. At the time of surgery, 6, 14, and 1 patients had Lichtman stages II, IIIA, and IIIB, respectively. Results: At the final follow-up visit, grip strength had improved from 65.4% to 79.7%, wrist extension had improved from 43° to 57°, and flexion had improved from 42° to 50°. There were no significant changes in the carpal height ratio, Stahl's index, or radioscaphoid angle. The mean VAS score was 1.7, and the mean DASH score was 6.9. The mean MMWS was 87.9, with excellent and good outcomes in 6 and 11 patients, respectively. Satisfactory Lichtman outcome scores were observed in 81%. Body mass index had a strong correlation and age had a weak correlation with MMWS (coefficient=−0.534, P=.013, and coefficient=−0.393, P=.078, respectively). Conclusion: The 4+5 ECA bone graft is effective for the treatment of Kienböck's disease in young patients with low body mass index. [Orthopedics. 2024;47(6)e292–e296.] [ABSTRACT FROM AUTHOR]

Lithium (Li) metal, with its unparalleled theoretical capacity and lowest electrochemical potential, is a promising anode material for rechargeable batteries. Yet, challenges such as dendrite formation, severe electrode volume change, and ongoing Li consumption impede its practical adoption. To address these challenges, a novel approach is introduced, harnessing the switchable electrical conductivity of a nanoporous current collector for Li metal anode. A vertically aligned Nickel‐catecholate (VANC) is directly grown on the copper foil as the nanoporous current collector, and the Li intercalation and de‐intercalation of VANC reversibly decrease and increase the electrical conductivity in the direction perpendicular to the electrode, respectively. The switchable conductivity induces uniform deposition and stripping of Li metal without forming dendrite and dead Li during the Li plating/stripping process and thus enables high coulombic efficiency of over 98% even after 200 cycles. This nanoporous structure with switchable conductivity will open up a new path for reliable lithium metal anode for rechargeable battery applications. [ABSTRACT FROM AUTHOR]

This study compared the results of endoscopic cubital tunnel release (eCuTR) with those of open cubital tunnel release (oCuTR) for the management of cubital tunnel syndrome (CuTS). In this retrospective study, 35 patients underwent eCuTR or oCuTR. Group I and group II consisted of 16 patients undergoing eCuTR and 19 patients undergoing oCuTR, respectively. Patients were asked to report paresthesia and pain, and electromyography was performed. The Dellon and Bishop classifications were used. The Disabilities of the Arm, Shoulder and Hand (DASH) and visual analog scale (VAS) pain scores were recorded, as well as the key pinch strength and two-point discrimination. The incision length and operation duration were noted. The mean follow-up was 39 months. The mean operating time was longer in the endoscopy group (43 vs 22 minutes). Overall, 34.3% (n=12) of the cases were classified as Dellon grade II and 65.7% (n=23) were classified as Dellon grade III. According to the Bishop score, excellent or good results were obtained for 75% of the patients in the eCuTR group and 78.9% of the patients in the oCuTR group. In the eCuTR and oCuTR groups, all outcome measures improved after surgery: DASH score (preoperative, 37.7 vs 30.7; postoperative, 15.4 vs 20), VAS score (preoperative, 7.8 vs 7.3; postoperative, 4.3 vs 4.1), pinch strength (preoperative, 74 vs 66; postoperative, 93 vs 84), and two-point discrimination (preoperative, 5.6 vs 6.6; postoperative, 4.9 vs 4.5). No significant difference was apparent between the two techniques in outcomes. However, the endoscopic release had a higher reoperation rate and took twice as long to perform despite having a shorter incision. [Orthopedics. 2024;47(3):e119–e124.] [ABSTRACT FROM AUTHOR]

A self-switched biasing quadrature voltage-controlled oscillator (VCO) is presented. It is implemented by directly injecting the oscillation signal of one VCO core into the other VCO core through the divided tail current sources without additional active devices for coupling. The proposed coupling structure automatically switches the NMOS field-effect transistors used in VCO cores and current sources from strong inversion to accumulation. Since the deep switching of MOSFETs was reported to physically reduce flicker noise, the proposed quadrature VCO (QVCO) is expected to improve the phase noise performance, which is confirmed experimentally. The designed QVCO using 0.18-[micro]m CMOS technology operates from 1.86 to 2.2 GHz with a 17% frequency tuning range. The measured phase noise is from -129.1 to -134.5 dBc/Hz at a 1-MHz offset, which is really close to ideal simulation results with the NMOS model disabling the flicker noise components. The average measured phase noise is 7.2 dB below the simulated one with a flicker noise model, which verifies the physical reduction of flicker noise by deep switching of the MOSFET. The phase noise figure-of-merit ranges from 179 to 185 over the entire tuning range. The QVCO dissipates 20 mA from a 1.8-V supply. Index Terms--CMOS, current source splitting (CSS), phase noise, quadrature, self-switched biasing (SSB), voltage-controlled oscillator (VCO).

A high-power CMOS switch using a novel adaptive voltage swing distribution method in a multistack field-effect transistor (FET) scheme is proposed. The proposed adaptive voltage swing distribution method in multistack FETs is very effective in preventing unwanted channel formation with low control voltage supply in OFF-state FETs. This, in turn, increases power-handling capability when a large-signal voltage swing is applied. In the proposed CMOS switch, the behavior of the voltage swing in OFF-state multistack FETs shows a difference with respect to the level of input voltage swing. The characteristics of voltage swing distribution and leakage channel formation in the CMOS switch is fully analyzed with incorporation of the novel adaptive voltage swing distribution method into a three-stacked nMOS Rx switch in a standard 0.18-[micro]m triple-well CMOS process. In addition, linearity of the proposed technique is verified through the measurement data of the single-pole double-throw switches that employ the proposed technique in the Rx switch. Two different types of configurations are implemented and characterized at the Rx switches, which consist of four-stacked nMOS devices, to demonstrate the method of minimizing voltage stress issues on one of the multistacked FETs. Layout consideration was also taken to prevent interference between leakage signals at the substrate. The measured performance of the proposed design shows an input 0.3-dB compression point of 33.5 dBm at 1.9 GHz. To the best of our knowledge, this is the highest power-handling capability of a CMOS switch in a standard CMOS process ever reported. The insertion losses of the Tx and Rx switches are 1.6 and 1.9 dB, respectively, at 1.9 GHz. The isolation of the Tx and Rx switches is around 20 and 30 dB, respectively, at 1.9 GHz. Index Terms--Adaptive voltage swing distribution method, body-floating technique, CMOS switch, high-power switch, triple well.

This paper presents the design and analysis of low flicker-noise RF mixers in a 0.18-[micro]m CMOS process for C-band direct-conversion receivers. The low flicker-noise mixers are implemented by incorporating a double-balanced Gilbert-type configuration, the RF leakageless current bleeding technique, and the resonating technique for the tail capacitance. First, a double-balanced Gilbert-type mixer using the current bleeding technique has been fabricated and measured for lowering flicker corner frequency. Second, a double-balanced Gilbert-type mixer using the current bleeding technique with one resonating inductor has been designed to improve conversion gain and flicker-noise performance. Third, by using two separate inductors at the node between the current bleeding device and local oscillator switches, conversion gain and flicker-noise performance are significantly improved. A conventional Gilbert-type mixer without any technique has also been fabricated and measured for comparative purposes. The Gilbert-type mixer using the current bleeding technique with two resonating inductors has a measured conversion gain of 16.1 dB, a measured input third-order intercept point of -5 dBm, a measured noise figure of 9.8 dB at 1 MHz, and a flicker corner frequency of 125 kHz while consuming only 7 mW of dc power. To the best of our knowledge, the proposed mixer shows the lowest flicker corner frequency (125 kHz) with more than 15 dB of conversion gain in the CMOS process. Index Terms--CMOS mixer, current bleeding, direct-conversion receiver, flicker noise, Gilbert-type mixer.