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In order to compare the clinical effects of different access surgical approaches in the treatment of Schatzker type V and VI tibial plateau fractures, a total of 68 patients with Schatzker type V and VI tibial plateau fractures involving the posterior-lateral aspect admitted to our hospital from January 2020 to January 2022 were grouped based on the different surgical access approaches, of which Patients treated with medial combined posterior-lateral approach were recorded as Group A (n=34), and patients treated with posterior medial inverted L incision combined with anterior-lateral approach were recorded as Group B (n=34). The surgical indexes (operation time, intraoperative blood loss) of the two groups were observed and compared, and the clinical efficacy of the patients was evaluated based on the New York Surgical Hospital (HSS) scores and imaging review, as well as the postoperative complications and the quality of life of the patients. Through the experiment, the operation time and intraoperative blood loss index of group A were better than that of group B (P < 0.05); the HSS scores of the two groups were significantly improved with time (P < 0.05), and at the same time, based on the follow-up observation, there was no significant difference between the HSS scores of the two groups of patients in the period of 3, 6, and 12 months of follow-up (P > 0.05); up to the time of the last follow-up visit, the patients of the two groups had received the imaging examination, and no The mean knee range of motion in group A was 126. 32°±5. 48° (0-7°; 114-139°), and the mean knee range of motion in group B was 127.56°±6.78° (0-10°; 113-140°), and there was no statistically significant difference in the knee range of motion between the two groups (t=0.05). Range of motion was not statistically different (t=0.829, P=0.409); the incidence of postoperative complications in Group A was 14.71% (5/34) was slightly higher than the incidence of postoperative complications in Group B was 11.76% (4/34), but this difference was not significant (x2=0.128, P=0.720); the quality of life of patients in the two groups was improved over time (P 0.05). The above results showed that the operation time and intraoperative bleeding of the medial combined posterior-lateral approach were less than that of the posterior medial inverted L incision combined anterior-lateral approach. Still, there was no significant difference between the two in terms of clinical efficacy and safety. The choice of surgical approach should be determined by combining the characteristics of fracture morphology, the objective conditions of instrumentation, and the patient’s individuality.

The sudden outbreak of COVID-19 occurred in China at a time when colleges and universities would begin the Spring semester, and the complete lockdown of the entire country made it impossible for campuses to open after the one-month long winter vacation. Under the guidance of the Central Government's Ministry of Education, which is the highest authority of Chinese educational systems and is the supreme policy maker, all schools, including colleges and universities, moved classes online. Since the move was at such a short-notice and in a less prepared manner, the effectiveness of it remained a concern for administrators, teachers and students as a whole. This paper, using the quantitative and qualitative data provided by a Chinese university survey, aims to analyze the factors commonly used in academic researches to measure the effectiveness of its online classes under such an emergency circumstance, with perceptions of both students and teachers. The paper discusses the issues through its findings, by comparison of teaching vs. learning effectiveness, online vs. face-to-face classrooms. It further explores the solutions to improve online teaching and learning environment, and suggests that after the pandemic is over the online classes shall not be a new normal in Chinese higher education.

Poly(vinylidene fluoride) (PVDF)-based composite solid electrolytes (CSEs) are attracting widespread attention due to their superior electrochemical and mechanical properties. However, the PVDF has a strong polar group -CF2-, which easily continuously reacts with lithium metal, resulting in the instability of the solid electrolyte interface (SEI), which intensifies the formation of lithium dendrites. Herein, Tetrafluoro-1,4-benzoquinone (TFBQ) was selected as an additive in trace amounts to the PVDF/Li-based electrolytes. TFBQ uniformly formed lithophilic quinone lithium salt (Li2TFBQ) in the SEI. Li2TFBQ has high lithium-ion affinity and low potential barrier and can be used as the dominant agent to guide uniform lithium deposition. The results showed that PVDF/Li-TFBQ 0.05 with a mass ratio of PVDF to TFBQ of 1:0.05 had the highest ionic conductivity of 2.39 × 10−4 S cm−1, and the electrochemical stability window reached 5.0 V. Moreover, PVDF/Li-TFBQ CSE demonstrated superior lithium dendrite suppression, which was confirmed by long-term lithium stripping/sedimentation tests over 2000 and 650 h at a current of 0.1 and 0.2 mA cm−2, respectively. The assembled solid-state LiNi0.6Co0.2Mn0.2O2||Li cell showed an excellent performance rate and cycle stability at 30 °C. This study greatly promotes the practical research of solid-state electrolytes. [ABSTRACT FROM AUTHOR]

All-inorganic layered halide perovskite CsPb2Br5 has many potential applications due to its interesting optical properties and long-term stability. However, its photoluminescence mechanism remains controversial due to the contradiction between its indirect bandgap nature and experimental observation of efficient green emission. The optical properties of CsPb2Br5 are highly dependent on the sample quality and preparation method, which is partially responsible for the controversy. Here, we prepared high-quality millimeter sized CsPb2Br5 single crystals using a saturated solvent evaporation crystallization method. The non-emissive CsPb2Br5 single crystals were found to convert into highly efficient green emitters with emission enhancement of up to four orders of magnitude by a simple thermal annealing process or irradiation with UV light or femtosecond laser pulses via multi-photon absorption. Through comprehensive characterization studies and theoretical calculations, a mechanism of the thermally induced indirect-to-direct bandgap transition associated with defect formation was proposed to explain the dramatic change in the optical properties of CsPb2Br5. [ABSTRACT FROM AUTHOR]

Because they are safer and less costly than state-of-the-art Li-ion batteries, aqueous zinc-ion batteries (AZIBs) have been attracting more attention in stationary energy storage and industrial energy storage. However, the electrochemical reaction of H + in all of the cathode materials of AZIBs has been puzzling until now. Herein, highly oriented VO 2 monocrystals grown on a Ti current collector (VO 2 -Ti) were rationally designed as the research model, and such a well-aligned VO 2 cathode also displayed excellent zinc-ion storage capability (e.g., a reversible capacity of 148.4 mAh/g at a current density of 2 A/g). To visualize the H + reaction process, we used time-of-flight secondary-ion mass spectrometry. With the benefit of such a binder-free and conductor-free electrode design, a clear and intuitive reaction of H + in a VO 2 cathode is obtained, which is quite significant for unraveling the accurate reaction mechanism of VO 2 in AZIBs.

An algorithm using wavelets and Kalman filtering method has been developed for QRS detection. The algorithm takes following steps: i) We use a RLS adaptive algorithm to establish a model of the electrocardiogram. Thus the algorithm can change its own model according to the change of the electrocardiogram. ii) Based on the model established in stage i), we combined the wavelet and Kalman Algorithm, decomposed the signal to several scales, filtering the signal in each scale. And then, iii)A decision rule is used to determine the QRS complex. The method was tested on ECG data form the MIT database, and experimental results show that the method is effective, and the influence of the noise can be eliminated.