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Biomedical magnesium alloys exhibit high specific strength, low density, proper elastic modulus, biodegradability, good biocompatibility and biomechanical compatibility, thus show extensive application perspective in bone fixation and cardiovascular stent.However, fast and nonuniform corrosion of magnesium alloys may easily cause the premature loss of mechanical integrity that restricts their clinical application in load bearing. In this paper, the research progress of magnesium alloys was systematically reviewed from the aspects of corrosion modes, the intrinsic and external factors affecting corrosion resistance, improvement of intrinsic corrosion resistance and surface modification, and the future development trend of corrosion resistance of biomedical magnesium alloys was prospected. On the one hand, the corrosion resistance of magnesium alloys can be improved by means such as low alloying, high purification and fine crystallization. On the other hand, reliable coatings are designed from the aspects of corrosion resistance, antibacterial and drug loading. In addition, corrosion media, flow field, stress and other in-body service factors should be considered comprehensively to study the corrosion degradation behavior and mechanism of magnesium alloy implanted devices.

Our study investigates the genetic mechanisms underlying the spotted leaf phenotype in rice, focusing on the spl43 mutant. This mutant is characterized by persistent reddish-brown leaf spots from the seedling stage to maturity, leading to extensive leaf necrosis. Using map-based cloning, we localized the responsible locus to a 330 Kb region on chromosome 2. We identified LOC_Os02g56000, named OsRPT5A, as the causative gene. A point mutation in OsRPT5A, substituting valine for glutamic acid, was identified as the critical factor for the phenotype. Functional complementation and the generation of CRISPR/Cas9-mediated knockout lines in the IR64 background confirmed the central role of OsRPT5A in controlling this trait. The qPCR results from different parts of the rice plant revealed that OsRPT5A is constitutively expressed across various tissues, with its subcellular localization unaffected by the mutation. Notably, we observed an abnormal accumulation of reactive oxygen species (ROS) in spl43 mutants by examining the physiological indexes of leaves, suggesting a disruption in the ROS system. Complementation studies indicated OsRPT5A's involvement in ROS homeostasis and catalase activity regulation. Moreover, the spl43 mutant exhibited enhanced resistance to Xanthomonas oryzae pv. oryzae (Xoo), highlighting OsRPT5A's role in rice pathogen resistance mechanisms. Overall, our results suggest that OsRPT5A plays a critical role in regulating ROS homeostasis and enhancing pathogen resistance in rice. [ABSTRACT FROM AUTHOR]

To compare the new zero-profile (Zero-P) fusion cage with regular cage and plate (CP) in the treatment of anterior cervical single-level cervical degenerative diseases. Patients operated from January 2013 to August 2018 were enrolled. They were divided into the Zero-P group (n = 74 cases) and CP groups (n = 116 cases). Follow-up assessment was at 1, 3, 12, and 24 months after surgery, including the incidence of dysphagia, visual analogue scale (VAS) score, Japanese orthopaedic association (JOA)score, C2-C7 Cobb angle, intervertebral disc height (IDH) and adjacent joint degeneration. The operation time and blood loss of patients in Zero-P group were less than those in the CP group, and there was no difference in hospitalization time. All 190 patients were followed up for 24 to 72 months, with an average of 35.29 months. In terms of clinical outcomes, vas and JOA scores of the two groups were significantly improved at one month and the last follow-up. The incidence of dysphagia in the Zero-P group was lower than that in the CP group. On radiological effects, Cobb angle and IDH showed significant correction in both groups, but the degeneration rate of adjacent joints in the Zero-P group was lower than the CP group. In ACDF, the clinical and radiological results of Zero-P and CP devices are satisfactory, but Zero-P cage may be superior in operation time, blood loss, the incidence of dysphagia and adjacent joint degeneration. [ABSTRACT FROM AUTHOR]

The red beds are widely distributed in Yunnan, Guizhou, Sichuan and Southeast Asia. This material is not suitable as subgrade filling due to seriously weathering and its softening characteristic after absorbing water. In the project of the section between Chengdu and Ya'an of Sichuan-Tibet Railway, the graded weakly weathered red-mudstone fragments was added to red beds subgrade fillers with specific proportion to improve size distribution and compactness of the material. The stress-strain characterization of improved red beds subgrade fillings has been obtained from laboratory test. A method of randomly generating fragment geometry model with concave convex polyhedron shape has been proposed. Based on the numerical compression model established by PFC3D, the proportion of different strong force chains during loading and probability density distribution at the peak intensity have been studied. The results show that the improved red beds subgrade fillings with the stone content of 50% performs better mechanically with good deformation characteristics, and its unconfined compressive strength is 421.9 kPa. The fragments form super chains easily by friction under bond strength of red clay and that strengthens the system. The mechanical properties degree of improved red beds subgrade fillers follows the order of the stone content 50%> 40%> 60%. Therefore, it is recommended to add 50% of weakly weathered red-mudstone fragment as the subgrade fillings when improving the red bed clay of the Sichuan-Tibet Railway.

Triethylamine (TEA) is an effective medium for inhibiting dye aggregation and improving the luminescence of dye-sensitized lanthanide-doped upconversion nanoparticles (UCNPs). However, excessive TEA will cause quenching of upconversion luminescence. In this paper, the possible mechanism of TEA affecting upconversion luminescence is discussed. It is found that TEA can enhance the nucleophilicity of the solvent, leading to dye shedding from the nanoparticles. Reducing the dielectric constant of the solvent can make TEA play a more positive role in upconversion luminescence and photostability of dye-sensitized UCNPs. When heptanol is selected as the solvent for CyBSO-sensitized β-NaYF4:20%Yb3+,2%Er3+ (UNs), TEA can increase the upconversion luminescence by 6.0 times relative to that in methanol. More importantly, the optimal content of TEA in heptanol is 3700 times more than that in methanol. Under the action of large amounts of TEA in heptanol, a novel upconversion nanoprobe for detecting ascorbic acid is developed with a limit of detection of 0.103 μM and high selectivity over potential interfering species. Meanwhile, the high concentration of TEA in heptanol can improve the photostability of CyBSO-sensitized UNs by 10.4 times, which is of paramount importance for the practical application of dye-sensitized UCNPs. [ABSTRACT FROM AUTHOR]

Background: The transoral endoscopic thyroidectomy by vestibular approach (TOETVA) has been developed for papillary thyroid carcinoma (PTC) treatment with satisfactory results. However, there were few malignant thyroid nodules ≥2 cm in previous studies of TOETVA. Therefore, we conducted this study to evaluate the results of treatment by TOETVA for PTC with tumor size ≥2 cm. Materials and Methods: The clinical characteristics and surgical outcomes of 10 PTC patients with tumor size ≥2 cm who underwent TOETVA in our center from June 2018 to August 2021 were, respectively, reviewed. Results: All 10 included PTC patients successfully underwent TOETVA and the mean tumor size was 2.5 ± 0.5 cm. The mean number lymph nodes dissected was 9.6 ± 2.9, and 3.1 ± 3.3 positive lymph nodes were discovered. Postoperatively, transient hypoparathyroidism was recorded in 2 patients (20%), transient recurrent laryngeal nerve injury was noted in 1 patient (10%), transient superior laryngeal nerve injury was noted in 1 patient (10%), and numb chin was identified in 1 patient (10%). The postoperative complications aforementioned recovered within 6 months. During a median follow-up of 23.8 ± 13.1 months, no other complications or tumor recurrence were found. Conclusions: TOETVA is feasible for PTC patients with tumor size ≥2 cm and satisfactory short-term surgical outcomes have achieved in this study. We suggested that experienced surgeons can gradually expand the indications for TOETVA. [ABSTRACT FROM AUTHOR]