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Objective: This study analyzes the therapeutic effect of arthroscopy-assisted minimally invasive surgery in patients with tibial plateau fractures (TPFs) and its influence on knee function and range of motion (ROM) recovery. Methods: This study enrolled 84 patients with TPFs admitted to the researchers' hospital between March 2021 and May 2022 as the study subjects, including 42 patients treated with open reduction and internal fixation (observation group) and 42 patients treated with arthroscopy-assisted minimally invasive surgery (experimental group). Then, perioperative indexes, knee symptom scores, knee function scores, knee ROM, and postoperative complications were compared between these two groups. Results: Surgery time was significantly shorter, intraoperative bleeding was less, and the time of the first off-bed activity was signally earlier in the experimental group than in the observation group (P < .05). All postoperative Lysholm and Rasmussen scores in both groups increased compared with preoperative scores, and the degree of increase was higher in the experimental group than in the observation group (P < .05). The range of flexion, extension, and internal/external rotation angles of patients was more extensive in both groups after surgery than before surgery, and the improvement of the experimental group was greater than that of the observation group (P < .05). The experimental group had a considerably lower incidence of postoperative complications than the observation group (P < .05). Conclusion: Arthroscopy-assisted minimally invasive surgery is highly effective in treating TPFs. Specifically, this surgery further improves knee symptoms, promotes the recovery of knee function, elevates knee ROM, and reduces the risk of postoperative complications compared to traditional open reduction and internal fixation.
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Film cooling technology is of great significance to enhance the performance of aero-engines and extend service life. With the increasing requirements for film cooling efficiency, researchers and engineers have carried out a lot of work on the precision and digital measurement of cooling holes. Based on the above, this paper outlines the importance and principles of film cooling technology and reviews the evolution of cooling holes. Also, this paper details the traditional measurement methods of the cooling hole used in current engineering scenarios with their limitations and categorizes digital measurement methods into five main types, including probing measurement technology, optical measurement technology, infrared imaging technology, computer tomography (CT) scanning technology, and composite measurement technology. The five types of methods and integrated automated measurement platforms are also analyzed. Finally, through a generalize and analysis of cooling hole measurement methods, this paper points out technical challenges and future trends, providing a reference and guidance for forward researches.
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Absolute distance measurements based on optical frequency combs (OFCs) have greatly promoted advances in both science and technology, owing to the high precision, large non-ambiguity range (NAR), and a high update rate. However, cyclic error, which is extremely difficult to eliminate, reduces the linearity of measurement results. In this study, we quantitatively investigated the impact of cyclic error on absolute distance measurement using OFCs based on two types of interferometry: synthetic wavelength interferometry and single-wavelength interferometry. The numerical calculations indicate that selecting a suitable reference path length can minimize the impact of cyclic error when combining the two types of interferometry. Recommendations for selecting an appropriate synthetic wavelength to address the tradeoff between achieving a large NAR and minimizing the risk of failure when combining the two methods are provided. The results of this study are applicable not only in absolute distance measurements but also in other applications based on OFCs, such as surface profile, vibration analysis, etc.
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Lithium metal batteries hold great promise for promoting energy density and operating at low temperatures, yet they still suffer from insufficient Li compatibility and slow kinetic, especially at ultra-low temperatures. Herein, we rationally design and synthesize a new amphiphilic solvent, 1,1,2,2-tetrafluoro-3-methoxypropane, for use in battery electrolytes. The lithiophilic segment is readily to solvate Li+ to induce self-assembly of the electrolyte solution to form a peculiar core-shell-solvation structure. Such unique solvation structure not only largely improves the ionic conductivity to allow fast Li+ transport and lower the desolvation energy to enable facile desolvation, but also leads to the formation of a highly robust and conductive inorganic SEI. The resulting electrolyte demonstrates high Li efficiency and superior cycling stability from room temperature to -40 °C at high current densities. Meanwhile, anode-free high-voltage cell retains 87 % capacity after 100 cycles.
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A high-energy and low repetition rate dispersion-mapped amplifier similariton oscillator with a large net intracavity anomalous dispersion and a linear cavity configuration is demonstrated experimentally at 1 µm. The numerical results confirm that self-similar evolution is accomplished in the gain fiber, and both the parabolic- and Gauss-shaped pulses can be emitted at different ports of the cavity, respectively. The maximum output power of 820 mW at a repetition rate of 8.6 MHz under a pump power of 12.76 W, corresponding to a pulse energy as high as of 95 nJ has been obtained.
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Yb-doped fluoride crystals are of important another Yb-doped laser materials besides Yb-doped oxide, which are becoming one of interests for developing tunable lasers and ultrafast lasers. In this paper, the systematic and contrastive experiments of the optical spectral characteristics are presented for two types of home-made novel Yb-doped fluoride laser crystals, namely, Yb-doped CaF2-SrF2 mixed crystal and co-doped Yb, Y:CaF2 single crystal. The fluorescent features of Yb-doped CaF2-SrF2 mixed crystal and co-doped Yb, Y:CaF2 single crystal are apparently different by the fluorescence experiment. The physical mechanism of these fluorescence spectra were analyzed and proposed. The influence of doping concentrations of active Yb(3+) ions or co-doping Y ions on the absorption of Yb-doped CaF2-SrF2 mixed crystal and co-doped Yb, Y:CaF2 single crystal was experimentally investigated, and the optimal values of doping concentrations of active Yb(3+) ions or co-doping Y ions in the two types of fluoride laser crystals were obtained. Continuous-wave laser operation for the two novel fluoride laser crystals has been achieved in three-mirror-folded resonator using a laser diode as the pump source. Therein, the laser operation for the co-doped Yb, Y:CaF2 crystal is demonstrated for the first time. For the two types of fluoride laser crystals (four samples), the input-output power relational curves, the optical slope efficiencies and the laser spectra were demonstrated by the laser experiments. By comparisons between the two types of fluoride laser crystals in the absorbability, fluorescence and laser spectra, laser threshold and slope efficiency of the continuous-wave laser operation, the results show that the best one of the four samples in spectral and laser characteristics is co-doped 3at%Yb, 6at% Y:CaF2 single crystal, which has an expected potential in the application. The research results provide available references for improving further laser performance of Yb-doped fluoride crystals.
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1,2-Dimethoxyethane (DME) has been considered as the most promising electrolyte solvent for Li-metal batteries (LMBs). However, challenges arise from insufficient Li Coulombic efficiency (CE) and poor anodic stability associated with DME-based electrolytes. Here, we proposed a rational molecular design methodology to tailor electrolyte solvation for stable LMBs, where shortening the middle alkyl chain of the solvent could reduce the chelation ability, while increasing the terminal alkyl chain of the solvent could increase the steric hindrance, affording a diethoxymethane (DEM) solvent with ultra-weak solvation ability. When serving as a single solvent for electrolyte, a peculiar solvation structure dominated by contact ion pairs (CIPs) and aggregates (AGGs) was achieved even at a regular salt concentration of 1 m, which gives rise to anion-derived interfacial chemistry. This illustrates an unprecedentedly high Li||Cu CE of 99.1% for a single-salt single-solvent (non-fluorinated) electrolyte at â¼1 m. Moreover, this 1 m DEM-based electrolyte also remarkably suppresses the anodic dissolution of Al current collectors and significantly improves the cycling performance of high-voltage cathodes. This work opens up new frontiers in engineering electrolytes toward stable LMBs with high energy densities.
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Chromium (Cr(VI)) is highly toxic and carcinogenic. Cr(VI) water pollution has become more and more serious. This article reports on a study in which lotus seed pods (LSP), an agricultural waste product, was used to efficiently remove Cr(VI) from an aqueous solution, and the carbonization product of LSP after the removal of Cr(VI) (CPLSP) can be regarded as a resource containing Cr. Cr(VI) removed by LSP fits a pseudo-second-order model. pH levels greatly influence the amount of Cr removed. The maximum removal of Cr(VI) by LSP in aqueous solution was 153.85 mg/g. The possible removal mechanism is absorption, redox, and reabsorption based upon SEM/EDS, FT-IR, and XPS spectra results. The Cr content of CPLSP was 42.95% by ammonium persulfate oxidation titrimetric method. These results suggest that LSP can be an excellent, low cost, biomaterial for removing and enriching Cr(VI) from an aqueous solution. PRACTITIONER POINTS: Lotus seed pods are an efficient adsorbent for Cr(VI) from aqueous solutions. The Cr removal by lotus seed pods occurs via absorption, redox, and reabsorption. Cr can be captured after the pods are carbonized. Lotus seed pods can be applied to the removal and enrichment of Cr(VI) from waste water.
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Lotus , Poluentes Químicos da Água , Purificação da Água , Adsorção , Cromo , Concentração de Íons de Hidrogênio , Cinética , Sementes , Soluções , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Osteoarthritis (OA) is the most common form of arthritis and is caused by the breakdown of joint cartilage. The present study aimed to investigate an effective method for the treatment of OA. It was demonstrated that, compared with other patients, patients with OA exhibited lower mRNA expression levels of SMAD family member 2 (SMAD2). MicroRNA (miR)4865p was predicted to bind with SMAD2, which was verified by dualluciferase reporter assay. Compared withcontrol patients who had no known history of OA or rheumatoid arthritis, patients with OA exhibited higher miR4865p expression level. Treatment with miR4865p mimics inhibited proliferation and migration of CHON001 human chondrocytes, and also inhibited the expression levels of type II collagen and aggrecan. However, treatment with a miR4865p inhibitor promoted proliferation and migration, and the expression of type II collagen and aggrecan. Short interfering RNAdirected silencing of SMAD2 reversed the upregulated proliferation and migration and the expression level of type II collagen and aggrecan induced by the miR4865p inhibitor. In conclusion, the results of the present study indicated that miR4865p was upregulated in OA and may inhibit chondrocyte proliferation and migration by suppressing SMAD2.