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The geometrical structure, defect formation energies, electrical and optical properties of C and/or Cr doped anatase TiO2 are calculated by GGA + U method under the framework of density functional theory. The relationship between band structure and light absorption is revealed. The results show that the lattice is obviously distorted after doping, and the stability of C and Cr co‐doping is higher than just Cr doping, second only to Cr doped TiO2. The contribution of C is forming impurity energy levels, and the contribution of Cr is to reduce the band gap in the single doped system. In the co‐doped system, Cr atoms are used as donor impurities and C atoms act as acceptor impurities. The impurity energy is composed of C 2p and Cr 3d orbital hybridization, which reduces the band gap and promotes the separation of the impurity levels. C and Cr co‐doping expands the light absorption of TiO2 to the entire visible region, thereby increasing the absorption coefficient and effectively enhancing the photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

Background: Lumbar radicular pain (LRP) is a common but challenging clinical symptom. Pulsed radiofrequency (PRF), a neuromodulation technique that uses short pulses of radiofrequency current, is effective in treating various pain disorders. However, few studies have been conducted on the effects of PRF and its modifying parameters., Objectives: Our study aimed to determine the intraoperative parameters of PRF of the lumbar dorsal root ganglion (DRG) that are related to clinical effects in patients with LRP unresponsive to transforaminal epidural steroid injections (TFESI)., Study Design: Prospective double-blind randomized controlled trial, pilot study., Setting: Single medical center in the Republic of Korea., Methods: Patients were allocated to one of 2 groups, high-voltage (60 V) or standard-voltage (45 V), according to the preset maximum voltage at which the active tip temperature does not exceed 42°C. Intraoperative parameters, such as output current, sensory threshold, and impedance, were measured. The primary outcomes were radicular pain intensity, physical functioning, global improvement and satisfaction with treatment, and adverse events. The assessments were performed up to 3 months postprocedure., Results: The patients in the standard-voltage group showed significant improvements in the Numeric Rating Scale pain score (P = 0.007) and Oswestry Disability Index (ODI) (P = 0.008) scores at 3 months post-PRF; however, no difference was observed in the high-voltage group. Among the intraoperative parameters, the output current showed a significant negative linear relationship with analgesic efficacy. The output current also showed a significant association with pain intensity (P = 0.005, R2 = 0.422) and ODI score (P = 0.004, R2 = 0.427) at 3 months postprocedure in a multiple regression analysis. The optimal cut-off value of the output current to lower pain intensity after 3 months was 163.5 mA with a sensitivity of 87.5%, specificity of 100%, and an area under the receiver operating characteristic curve value of 0.92 (95% CI. 0.76 - 1.00)., Limitations: Limitations of our study include an imbalance of baseline characteristics, small sample sizes, and short follow-up periods., Conclusions: Lower output currents during PRF application to the lumbar DRG were associated with greater analgesic effects in patients who did not respond to therapeutic TFESI.

Objectives: In this study, we aimed to provide a more valuable diagnostic parameter and more equivocal assessment of the diagnostic potential of patellofemoral pain syndrome (PFPS) by comparing the quadriceps tendon cross-sectional area (QTCSA) with the quadriceps tendon thickness (QTT), a traditional measure of quadriceps tendon hypertrophy., Patients and Methods: Between March 2014 and August 2020, a total of 30 patients with PFPS (16 males, 14 females; mean age, 30.4±11.2 years; range, 16 to 49 years) and 30 healthy individuals (19 males, 11 females; mean age: 30.8±13.8 years; range, 17 to 62 years) who underwent knee magnetic resonance imaging (MRI) were retrospectively analyzed. T1-weighted turbo spin-echo transverse MRI scans were obtained. The QTCSA was measured on the axial angled phases of the images by drawing outlines, and the QTT was measured at the most hypertrophied quadriceps tendon., Results: The mean QTT and QTCSA in the patients with PFPS (6.33±0.80 mm and 155.77±36.60 mm2, respectively) were significantly higher than those in the control group (5.77±0.36 mm and 111.90±24.10 mm2, respectively; p<0.001, for both). The receiver operating characteristic curve was used to confirm the sensitivities and specificities for both the QTT and QTCSA as predictors of PFPS. The optimal diagnostic cut-off value for QTT was 5.98 mm, with a sensitivity of 66.7%, a specificity of 70.0%, and an area under the curve (AUC) of 0.75 (range, 0.62 to 0.88). The optimal diagnostic cut-off value for QTCSA was 121.04 mm2, with a sensitivity of 73.3%, a specificity of 70.0%, and an AUC of 0.83 (range, 0.74 to 0.93)., Conclusion: Based on our study results, the QTCSA seems to be a more reliable diagnostic indicator for PFPS than QTT.

The hydrochlorination process is a necessary technological step for the production of polycrystalline silicon using the Siemens method. In this work, the adsorption behaviors of silicon tetrachloride (SiCl 4 ), silicon dichloride (SiCl 2 ), dichlorosilane (SiH 2 Cl 2 ), trichlorosilane (SiHCl 3 ), HCl, and H 2 on the Si(100) surface were investigated by first-principles calculations. The different adsorption sites and adsorption orientations were taken into account. The adsorption energy, charge transfer, and electronic properties of different adsorption systems were systematically analyzed. The results show that all of the molecules undergo dissociative chemisorption at appropriate adsorption sites, and SiHCl 3 has the largest adsorption strength. The analysis of charge transfer indicates that all of the adsorbed molecules behave as electron acceptors. Furthermore, strong interactions can be found between gas molecules and the Si(100) surface as proved by the analysis of electronic properties. In addition, SiCl 2 can be formed by the dissociation of SiCl 4 , SiH 2 Cl 2 , and SiHCl 3 . The transformation process from SiCl 4 to SiCl 2 is exothermic without any energy barrier. While SiH 2 Cl 2 and SiHCl 3 can be spontaneously dissociated into SiHCl 2 , SiHCl 2 should overcome about 110 kJ/mol energy barrier to form SiCl 2 . Our works can provide theoretical guidance for hydrochlorination of SiCl 4 in the experimental method., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)