RESUMEN
In response to the urgent need for advanced climate change mitigation tools, this study introduces an innovative CO2 gas sensor based on p-p-type heterostructures designed for effective operation at room temperature. This sensor represents a significant step forward, utilizing the synergistic effects of p-p heterojunctions to enhance the effective interfacial area, thereby improving sensitivity. The incorporation of CuO nanoparticles and rGO sheets also optimizes gas transport channels, enhancing the sensor's performance. Our CuO/rGO heterostructures, with 5 wt % rGO, have shown a notable maximum response of 39.6-500 ppm of CO2 at 25 °C, and a low detection limit of 2 ppm, indicating their potential as high-performance, room-temperature CO2 sensors. The prepared sensor demonstrates long-term stability, maintaining 98% of its initial performance over a 30-day period when tested at 1-day intervals. Additionally, the sensor remains stable under conditions of over 40% relative humidity. Furthermore, a first-principles study provides insights into the interaction mechanisms with CO2 molecules, enhancing our understanding of the sensor's operation. This research contributes to the development of CO2 monitoring solutions, offering a practical and cost-effective approach to environmental monitoring in the context of global climate change efforts.
RESUMEN
BACKGROUND: Windswept deformity (WSD) in relation to advanced osteoarthritis (OA) presents a significant surgical challenge in total knee arthroplasty (TKA). The primary goal of this study is to investigate the Prevalance of WSD associated osteoarthritis who have undergone total knee arthroplasty. The secondary goal is to explore the causes of WSD and its association with spinal deformity or leg length discrepancy in these patients. Finally, we evaluate the surgical outcomes of phenotype-considered kinematically aligned TKA (KA-TKA) in treating patients with WSD. METHODS: A review was conducted on data from 40 knees of 33 WSD patients who underwent phenotype-considered KA-TKA from August 2016 to December 2020. Patient demographics, associated diseases, preoperative and postoperative knee alignment angles, range of motion (ROM), Oxford Knee Score (OKS), and Knee Society Score (KSS) were collected and analyzed. Subgroup analysis for comparing the results between valgus and varus knees were also performed. RESULTS: Within the studied cohort of WSD patients, a substantial 64% displayed concomitant coronal spinal imbalance and 21% evidenced leg length discrepancy. Postoperative improvements were notable in knee alignments, ROM, OKS, and KSS following the application of the phenotype-considered KA-TKA approach. There were significant differences in the knee alignment angles, including mHKA, LDFA, and MPTA, between the valgus and varus side of knees (P = 0.018). However, no statistically significant difference were observed in the functional scores, comprising ROM, OKS, and KSS, between valgus and varus knees. CONCLUSIONS: A high percentage of patients with WSD exhibited coronal spinal imbalance and leg length discrepancy. Phenotype-considered KA-TKA effectively provided alignment targets for the treatment of both varus and valgus knees in patients with WSD, achieving excellent short-term outcomes and acceptable knee alignment.
RESUMEN
A theoretical model is developed to study the polarization mode dispersion effect in an electro-optic Mach-Zehnder interferometric (MZI) modulator. The Stokes parameters and differential group delay (DGD) of the output light of a MZI modulator can be analytically derived with the proposed model, which is based on a three-dimensional Maxwell's wave equation approach. The theoretical model is validated to the extent possible by comparing the theoretical results of the Stokes parameters and DGD with experimental measurements that are based on the wavelength-scanning method and the Jones matrix eigenanalysis method.