electric vehicles. [1,2] However, the further scaled application of commercial LIBs encounters a "bottleneck": the overall energy density is approaching the ceiling due to the restriction of theoretical specific capacity of insertion-type oxide cathodes (≈250 mAh g −1 ) and graphite anodes (372 mAh −1 ). In order to satisfy the increasing demand for higher energy densities particularly under the extended application such as unmanned aerial vehicles, cargo aircraft, electric vehicles, and the exploration of novel storage system is of great significance. [3] Sulfur is earthabundant, low-cost, and environment friendly. More inspiring, lithium-sulfur batteries (LSBs) based on sulfur cathodes exhibit much higher theoretical specific capacity (1675 mAh g −1 ) through the multielectron redox reaction process, showing great potential for high-performance energy storage devices. [4] Despite the promising prospects, the practical application of LSBs is still impeded by several challenges, such as electrical insulation of sulfur and discharge products (Li 2 S/Li 2 S 2 ), severe shuttle effect of long-chain polysulfides (LiPSs, Li 2 S n , 4 ≤ n ≤ 8), low sulfur utilization, and large volume expansion (≈80%), which are critically fatal for the cycle stability and power density. [5] In the last decades, tremendous Lithium-sulfur batteries (LSBs) are severely impeded by their poor cycling stability and low sulfur utilization due to the inevitable polysulfide shuttle effect and sluggish reaction kinetics. This work reports a Mott-Schottky RGO-PANI/MoS 2 (RPM) heterogeneous layer modified separator for commercialsulfur-based LSBs through the vertical growth of molybdenum sulfide (MoS 2 ) arrays on the polyaniline (PANI) in situ reduced graphene oxide (RGO). Due to the synergistic effects of the "reservoir" constructed by MoS 2 and RGO-PANI, strong absorbability, high conductivity, and electrocatalytic activity, RPM exhibits a successive "trapping-interception-conversion" behavior toward lithium polysulfides. As a result, the LSBs assembled using a commercialsulfur as the cathode and RPM as modified layer exhibit high sulfur utilization (3.8 times higher than that of the unmodified separator at 5 C), excellent rate performance (553 mAh g −1 at 10 C), and outstanding high-rate cycle stability (524 mAh g −1 after 700 cycles at 5 C). Moreover, even at a high sulfur loading of 5.4 mg cm −2 , a favorable areal capacity of 3.8 mAh cm −2 is still maintained after 80 cycles. Theoretical calculations elucidate that such a systematic strategy can effectively suppress the shuttling effect and boost the catalytic conversion of intercepted polysulfides. This work may provide a feasible strategy to promote the practical application of commercial-sulfur-based LSBs.

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BackgroundIn anterior cervical discectomy and fusion (ACDF) surgery, drilling operation causes a high risk of tissue injury. This study aimed to present a novel feedback system based on sound pressure signals to identify drilling condition during ACDF.Material/MethodsACDF surgery was performed on the C4/5 segments of 6 porcine cervical specimens. The annulus fibrosus, endplate cartilage, sub-endplate cortical bone, and posterior longitudinal ligament (PLL) were drilled until penetration using a 2-mm high-speed burr. Sound pressure signals were collected using a microphone and dynamic signal analyzer. The recorded signals of different tissues were proceeded with lifting wavelet transform for extracting harmonic components. The frequencies of harmonic components are 1, 2, 3, 4, and 5 times higher than the motor frequency. The magnitude of harmonic components was calculated to identify different drilling conditions, along a broad spectrum of frequencies (1–5 kHz). For statistical analysis, one-way ANOVA (analysis of variance) and post hoc test (Dunnett’s T3) were performed.ResultsVery good demarcation was found among the signal magnitudes of different drilling conditions. Different drilling conditions do not present the same rate of variation of frequency. Differences in magnitude among all drilling conditions were statistically significant at certain frequency points (p<0.05). In 3 cases, one tissue could not be identified with respect to another (annulus fibrosus and endplate cartilage at 2 kHz, PLL and penetration at 3 kHz, annulus fibrosus and sub-endplate cortical bone at 5 kHz, p>0.05).ConclusionsSound pressure signals may provide an auxiliary feedback system for enhancing drilling operation in ACDF surgery, especially in minimally invasive surgery.

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Objective. This study aimed to optimize the CT images of anal fistula patients using a convolutional neural network (CNN) algorithm to investigate the anal function recovery. Methods. 57 patients with complex anal fistulas admitted to our hospital from January 2020 to February 2021 were selected as research subjects. Of them, CT images of 34 cases were processed using the deep learning neural network, defined as the experimental group, and the remaining unprocessed 23 cases were in the control group. Whether to process CT images depended on the patient’s own wish. The imaging results were compared with the results observed during the surgery. Results. It was found that, in the experimental group, the images were clearer, with DSC = 0.89, precision = 0.98, and recall = 0.87, indicating that the processing effects were good; that the CT imaging results in the experimental group were more consistent with those observed during the surgery, and the difference was notable ( P < 0.05 ). Furthermore, the experimental group had lower RP (mmHg), AMCP (mmHg) scores, and postoperative recurrence rate, with notable differences noted ( P < 0.05 ). Conclusion. CT images processed by deep learning are clearer, leading to higher accuracy of preoperative diagnosis, which is suggested in clinics.

BackgroundThe electrical properties of biological tissues differ depending on their physical properties. This study aimed to explore if bioelectrical impedance (modulus and phase) would discriminate tissues relevant to resection of the posterior longitudinal ligament (PLL) in anterior cervical decompression surgery.MethodsPLL resection via an anterior approach was performed on the C4/5 segments in six mini-pigs. The bioelectrical impedance measurements were performed for two tissue groups (annulus fibrosus, endplate cartilage, sub-endplate cortical bone, and PLL; PLL, dura mater, spinal cord, and nerve root) using a novel probe and a precision inductance-capacitance-resistance meter. For each group, impedance was analyzed in terms of modulus and phase along a broad spectrum of frequencies (200–3000 kHz) using a nonparametric statistical analysis (Kruskal-Wallis).ResultsThe analysis showed a clear difference among the tissues. The modulus and phase show the same changing trend with frequency and present lower values at higher frequencies. Among annulus fibrosus, endplate cartilage, sub-endplate cortical bone, and PLL, it was possible to discriminate each tissue at every frequency point, considering the phase (p < 0.05), while this was not always the case (i.e., annulus fibrosus vs PLL at frequency of 200 kHz, 400 kHz, and 3000 kHz, p > 0.05) for modulus. Among PLL, dura mater, spinal cord, and nerve root, for every comparison, a statistically significant difference was reported in the modulus, phase, or both (p < 0.05).ConclusionsThe results indicated the potential of bioelectrical impedance to provide real-time tissue differentiation and enhance safe PLL resection in anterior cervical decompression surgery, particularly in robot-assisted minimally invasive surgery (RMIS).

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