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To achieve specific construction requirements, such as the desired strength and flowability, the proportion of ultra-high performance concrete (UHPC) constituents must be carefully balanced. However, traditional concrete mixture design requires comprehensive trial-and-error experiments, which are cumbersome and costly. The requirements and objectives of a project may be contradictory, rendering the experimental design much more difficult. Therefore, to optimize the mixing ratio of UHPC, particle swarm optimization (PSO) was used to perform multi-objective optimization of the mechanical and flow properties of UHPC. The premise of comprehensive consideration of compressive strength and fluidity was given based on the Pareto optimality theory. The optimal ratio was validated through a combination of the macroscopic force phenomenon and microscopic mechanism. The findings show that the generated PSO algorithm model can simulate and analyze the complete relationship among all functional UHPC components, compressive strength, and fluidity and thus demonstrates its quite high accuracy and efficiency. The macro-micro test results indicate that the optimized UHPC ratio based on the PSO algorithm satisfies the best compressive strength and fluidity. The PSO algorithm can identify the direction for the optimization of the combination of UHPC multiple performance ratios. [ABSTRACT FROM AUTHOR]

The charge storage mechanism and capacity of supercapacitors completely depend on the electrochemical and mechanical properties of electrode materials. Herein, continuously reinforced carbon nanotube film (CNTF), as the flexible support layer and the conductive skeleton, was prepared via the floating catalytic chemical vapor deposition (FCCVD) method. Furthermore, a series of novel flexible self-supporting CNTF/polyaniline (PANI) nanocomposite electrode materials were prepared by cyclic voltammetry electrochemical polymerization (CVEP), with aniline and mixed-acid-treated CNTF film. By controlling the different polymerization cycles, it was found that the growth model, morphology, apparent color, and loading amount of the PANI on the CNTF surface were different. The CNTF/PANI-15C composite electrode, prepared by 15 cycles of electrochemical polymerization, has a unique surface, with a "sea-cucumber-like" 3D nanoprotrusion structure and microporous channels formed via the stacking of the PANI nanowires. A CNTF/PANI-15C flexible electrode exhibited the highest specific capacitance, 903.6 F/g, and the highest energy density, 45.2 Wh/kg, at the current density of 1 A/g and the voltage window of 0 to 0.6 V. It could maintain 73.9% of the initial value at a high current density of 10 A/g. The excellent electrochemical cycle and structural stabilities were confirmed on the condition of the higher capacitance retention of 95.1% after 2000 cycles of galvanostatic charge/discharge, and on the almost unchanged electrochemical performances after 500 cycles of bending. The tensile strength of the composite electrode was 124.5 MPa, and the elongation at break was 18.9%. [ABSTRACT FROM AUTHOR]

Objective: It aimed to investigate the difference in clinical efficacy between posterior cervical endoscopic discectomy (PCED) and Fenestration laminectomy discectomy (FLD) in cervical disc herniation (CDH)., Methods: This retrospective study analyzed 100 CDH patients undergoing nucleotomy and assigned them into the FLD and PCED groups, 50 cases for each group. The differences in operation time, intraoperative blood loss, skin incision, off-bed time, and hospital stay were evaluated. Numeric rating scales (NRS), Oswestry disability Index (ODI), Japanese Orthopaedic Association (JOA), excellent and good clinical efficacy, quality of life (QoL) SF-36 score, and complication rate were compared., Results: The results showed that compared with the FLD group, the PCED group had increased operation time, decreased intraoperative blood loss, skin incision length, off-bed time, and hospital stay (P < .01). Compared with the FLD group, the PCED group had decreased NRS and ODI scores and increased JOA scores at 1 d, 3 d, 1 month, 3 months, 6 months, 12 months, and 24 months after operation (P < .05). Compared with the FLD group, the excellent and good rate of the PCED group increased significantly after 6 months, 1 year, and 2 years (52.0% vs 64.0%, 58.0% vs. 80.0%, 68.0% vs 90.0%, P < .05). Relative to the FLD group, the physical function, emotional function, vitality, social function, and mental health score of the PCED group increased obviously at 2 years after operation (P < .01). The postoperative complication rate was 0% in both FLD and PCED groups. PCED has good long-term clinical efficacy in the treatment of CDH, with excellent recovery and high safety., Conclusion: PCED showed favorable long-term clinical efficacy in the treatment of CDH, with excellent recovery and high safety. Compared to FLD, PCED resulted in reduced intraoperative blood loss, shorter incision length, and faster recovery. It also led to improved pain scores, functional outcomes, and quality of life measures. The absence of postoperative complications further supports the use of PCED as an effective treatment option for CDH.

Background: Non-Hispanic Black (NHB) patients with early-onset colorectal cancer (EOCRC) are more likely to present with advanced-stage disease than their Non-Hispanic White (NHW) counterparts. To further elucidate whether differences in tumor biology or disparities in access to care may be responsible, we examined the association between race/ethnicity and initial stage of disease, time to diagnosis, and tumor characteristics among NHW and NHB patients with EOCRC cared for in a safety-net health care setting., Methods: We performed a retrospective cohort study of NHW and NHB patients diagnosed with primary EOCRC who received care at Boston Medical Center between January 2000 and May 2020. We compared demographics, risk factors, presenting signs/symptoms, time to diagnosis, health care utilization, and tumor characteristics (stage, grade, location, and mutational status)., Results: We identified 103 patients (mean age 41.5±7.2 y, 53.4% men), including 40 NHWs and 63 NHBs, with EOCRC. NHB and NHW patients were similar with respect to demographics, presenting signs/symptoms, and risk factor distribution. There were also no significant differences between NHWs and NHBs with respect to the advanced stage of disease at presentation (45.0% vs. 42.9%, P =0.83), the median time to diagnosis [152 d (IQR, 40 to 341) vs. 160 d (IQR, 61 to 312), P =0.79] or tumor characteristics, except for a predilection for proximal disease among NHBs (30.2% vs. 15.0%)., Conclusions: NHB patients were no more likely than NHW patients to present with advanced-stage disease, aggressive tumor histology, or experience delays in diagnosis within a safety-net health care system., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)