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In this work, the single-event burnout (SEB) performance and reasons of the proposed 900V SiC quasi-vertical double diffusion MOSFET with deepened drain (T-QVDMOSFET) are analyzed from the spatial distribution of physical quantities such as power density, lattice temperature and total current density by 2-D numerical simulation, and a SEB-hardened structure (TB-QVDMOSFET) with buried oxygen layer (BOX) and heavily doped N-type current expansion layer (CSL) inside the device is proposed. Simulation results indicate that when heavy-ion with linear energy transfer (LET) of 0.5pC/ $\mu $ m strikes the device, the primary cause of SEB in the SiC T-QVDMOSFET is the high transient current density and electric field at the trench gate corner. This phenomenon leads to increased power dissipation, resulting in excessive temperatures that ultimately cause thermal failure. The BOX and a heavily doped N-type CSL added in the SEB-hardened structure change the current flow path, and the transient current concentrated in the region is dispersed. This modification reduces the high current density and power dissipation at the trench corner, thereby significantly enhancing the device’s resistance to SEB. Compared to the original device, the SEB threshold voltage is increased from 270V to 478V, marking a 77% improvement.

BackgroundSjögren’s syndrome (SS) is a systemic autoimmune disease, with major symptoms including dry mouth and dry eyes, for which there is no effective treatment. Recent studies have demonstrated that mesenchymal stem cells (MSCs) are effective in the treatment of SS, but the efficacy of allogeneic MSCs is affected by variability among different cell donors, and they are easily cleared by the immune system of the recipient. Autologous MSCs are one of the ideal options for the treatment of SS; however, their function decreases with age. Regenerative fibroblast (rFib) is a type of new MSC obtained through chemical reprogramming technology from skin fibroblasts. In this study, we report the safety and efficacy of intravenous infusion of autologous rFib in a volunteer with SS.Case reportIn March 2021, the volunteer was diagnosed with SS due to positive anti-SSB antibodies, lymphocyte infiltration in the lip gland, dry eyes, and a large area of purpura in both lower limbs. From May 2021 to November 2022, she received allogeneic Umbilical cord mesenchymal stem cells (UCMSC) therapy (5.0 × 107 UCMSCs per time, totaling 10 infusions), but her condition did not improve. In May 2023, the rFib for the volunteer was prepared, meeting the quality standard of T/CSCB0003-2021 Human Mesenchymal Stem Cells. Between October 2023 and June 2024, the volunteer received a total of 12 intravenous transfusions of autologous rFib. After the treatments, the volunteer experienced no recurrence of purpura in both lower limbs. Symptoms of dry mouth, dry eyes, and fatigue were relieved. ESR, B lymphocytes, rheumatoid factor IgM, and IgA declined, while the proportion of NK cells increased, and most of the cytokines returned to normal levels. In vitro experiments showed that rFib could significantly inhibit the proliferation of T lymphocytes after PHA stimulation. No adverse effects were associated with the use of rFib in the volunteer during the clinical trial.SummaryThe results of this clinical trial indicate that intravenous injections of autologous rFib are both safe and effective for treating SS. Autologous rFib may be more suitable for treating autoimmune diseases than allogeneic MSCs.

Objective To identify risk factors associated with postoperative shoulder joint dysfunction in patients who underwent surgical intervention for acromioclavicular (AC) joint dislocation, with the aim of enhancing preoperative counselling, surgical planning, and postoperative management to optimize functional outcomes. Methods Patients who underwent surgery for AC joint dislocation between January 2018 and January 2023 at a hospital orthopaedic centre were enrolled into this retrospective study. Inclusion criteria were patients aged ≥18 years with a documented AC joint dislocation who underwent surgical treatment and had a minimum follow-up period >1 year. Patients with pre-existing shoulder conditions, prior shoulder surgeries, or incomplete medical records were excluded. Visual Analog Scale pain score ≥5 and Constant-Murley Score ≤70 was considered indicative of shoulder joint dysfunction. Statistical analyses included univariate and multivariate logistic regression to identify independent risk factors for postoperative shoulder joint dysfunction. Results Among 208 included patients, 56 (27%) exhibited shoulder joint dysfunction at the final follow-up. High-energy injury mechanisms, combined coracoclavicular ligament injuries, and lack of coronal plane congruity were identified as significant predictors of postoperative dysfunction. Specifically, high-energy injuries (odds ratio [OR] 5.493, 95% confidence interval [CI] 2.068, 14.590), combined coracoclavicular ligament injuries (OR 0.118, 95% CI 0.032, 0.432), and lack of coronal plane congruity (OR 2.540, 95% CI 1.197, 5.387) were associated with an increased risk of poor shoulder function postoperatively. Other factors, such as age, injury mechanism, and postoperative exercise compliance also contributed to the outcomes. Level of evidence: iv. Conclusions Injury mechanism, ligamentous injuries, and joint congruity are important in determining postoperative shoulder function. Accurate joint reduction and diligent postoperative rehabilitation are crucial for optimal recovery. These findings provide valuable insights for improving patient care and surgical outcomes in AC joint dislocation treatment. Further research is needed to validate these findings and explore additional factors that may influence postoperative shoulder function.

The emergence of tissue engineering provides an alternative therapeutic strategy for various regeneration. It is the crucial step for choosing an ideal scaffold to support the cellular behaviors of various functional cells. Various biomaterials have been found or synthesized and applied to tissue repair. Among these biomaterials, as a natural-derived material, decellularized extracellular matrix (dECM) derived from cells, tissues, and organs is attracting more and more interest due to its good biocompatibility, biodegradability, and the ability to mimic a microenvironment similar to extracellular matrix. More and more researchers utilized dECM derived from cells, tissues, and organs to fabricate tissue-engineered scaffolds to repair musculoskeletal tissues, since the bioactive molecules of dECM, such as fibrous proteins, proteoglycans, and adhesive glycoproteins, could provide various bioactive cues for tissue regeneration and remodeling. The physiochemical properties of dECM can be enhanced by changing decellularization and modification techniques. In addition, dECM can act as carriers of drugs, factors, or exosomes, delivering agents to injured tissues and promoting tissue repair and regeneration. Therefore, we conduct this review to discuss the current status and challenges of dECM in repairing the musculoskeletal system. Furthermore, the fabrication and modification of dECM were also discussed in our study.

A generalized three-dimensional mathematical model is built to study the influences of channel parameters (channel angle, channel section diameter, and channel distance) on the molten steel flow, heat transfer, and inclusion removal in the induction heating tundish. The results demonstrate that as the channel angle increases, the flow of molten steel in the discharging chamber gradually slows down. When the channel angle is 6°, the temperature of the discharging chamber is slightly lower than when the channel angles are 2° and 4°. When the channel angle is 2°, the inclusion removal rate is lower than when the channel angles are 4° and 6°, while the latter two have little difference. As the channel section diameter increases, the flow of molten steel in the discharging chamber gradually slows down. When the channel section diameter is 100 mm, the temperature distribution in the discharging chamber is uneven. While the temperature distributions of the discharging chamber are even and similar, when the channel section diameters are 150 and 200 mm. As the channel section diameter increases, the removal rate of inclusion gradually decreases. The variation of channel distance has little effect on the temperature distribution of the discharging chamber. When the channel distance is 600 mm, the removal rate of inclusion is lower than when the channel distances are 1,000 and 1,400 mm. Moreover, for the latter two, the removal rates of inclusions have little difference. For this model, the best channel angle is 4°, the best channel section diameter is 150 mm, and the best channel distance is 1,000 mm.