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Objectives: This study aims to clarify the effect of ferroptosis by P. gingivalis on periodontal epithelium impairment and potential mechanisms. Materials and methods: The expression of epithelial junction proteins (CDH1, OCLN, ZO-1), FTL and GPX4 in healthy and periodontitis tissues was analyzed using bioinformatics analysis and validated in vivo. An in vitro model was constructed to evaluate ferroptosis by mitochondria morphology, content of iron and GSH, and level of lipid peroxidation, FTL, GPX4 and SLC7A11. The iron concentration was changed with iron chelator DFO and iron supplementation FAC. The epithelial impairment was assessed by protein expression. To investigate the mechanism, si-MYB (a negative transcription factor of SLC7A11) and GPX4 inhibitor RSL3 were employed. Results: CDH1, OCLN, ZO-1 and GPX4 expression was decreased, while FTL expression was elevated in periodontitis tissues. Infected cells showed ferroptosis change of the mitochondria with higher level of lipid peroxidation, iron, FTL and lower level of GPX4, GSH, SLC7A11. FAC augmented ferroptosis and weakened epithelial junction, while DFO exhibited a counteractive effect. Silencing MYB rescued SLC7A11, GPX4 and epithelial junction proteins, which was hindered by RSL3. Conclusions: Our study demonstrated that P. gingivalis weakened the oral epithelial barrier by causing ferroptosis via inhibiting SLC7A11/GSH/GPX4 axis. [ABSTRACT FROM AUTHOR]

Background: Non‐Hodgkin lymphoma (NHL) is one of the most common haematologic malignancies in the world. Despite substantial efforts to identify causes and risk factors for NHL, its aetiology is largely unclear. Autoimmune diseases have long been considered potential risk factors for NHL. We carried out Mendelian randomisation (MR) analyses to examine whether genetically predicted susceptibility to ten autoimmune diseases (Behçet's disease, coeliac disease, dermatitis herpetiformis, lupus, psoriasis, rheumatoid arthritis, sarcoidosis, Sjögren's syndrome, systemic sclerosis, and type 1 diabetes) is associated with risk of NHL. Methods: Two‐sample MR was performed using publicly available summary statistics from cohorts of European ancestry. For NHL and four NHL subtypes, we used data from UK Biobank, Kaiser Permanente cohorts, and FinnGen studies. Results: Negative associations between type 1 diabetes and sarcoidosis and the risk of NHL were observed (odds ratio [OR] 0.95, 95% confidence interval [CI]: 0.92–0.98, p = 5 × 10−3, and OR 0.92, 95% CI: 0.85–0.99, p = 2.8 × 10−2, respectively). These findings were supported by the sensitivity analyses accounting for potential pleiotropy and weak instrument bias. No significant associations were found between the other eight autoimmune diseases and NHL risk. Conclusion: These findings suggest that genetically predicted susceptibility to type 1 diabetes, and to some extent sarcoidosis, might reduce the risk of NHL. However, future studies with different datasets, approaches, and populations are warranted to further examine the potential associations between these autoimmune diseases and the risk of NHL. [ABSTRACT FROM AUTHOR]

A method for the oxidation life analysis of SiC/SiC composite structures was proposed to predict the oxidation life of ceramic matrix composite (CMC) components. In this paper, multiscale diffusion–oxidation simulation of the CMCs' structure can be carried out by establishing the equivalent diffusion coefficient model, to get the microscopic oxidation morphology parameters at each point. Based on the results, the residual stiffness is calculated with the homogenization method. Then, the residual stiffness is taken as the material parameter of element to calculate the stress distribution after oxidation in the CMC structure. And the residual strength of CMCs was calculated by progressive damage analysis. The oxidation life of CMC component is analyzed by judging the failure condition of each element. Finally, the oxidation life prediction of the CMC adjustment sheet under specific loading environment is realized, which is about 1 200 h. The results show that this method is feasible for the calculation of hot end parts under actual complex loads. [ABSTRACT FROM AUTHOR]

The titanium-containing oxide film has attracted attention due to the phenomenon of self-sealing pores. The influences of fluorotitanate (K2TiF6), phytic acid (H12Phy) and sodium fluoride(NaF) concentrations as well as final voltage on corrosion resistance of oxide film were investigated by an orthogonal experiment with four factors and three levels. The coating performances were characterized by using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and electrochemical methods. The results show that the sequence of processing factors on the corrosion resistance of oxide film is H12Phy concentration > NaF concentration > final voltage > K2TiF6 concentration. Anodic coatings are mainly composed of TiO2, MgF2, Mg2PO4F and Mg2TiO4. Micro-arc oxidation (MAO) coating can significantly improve the corrosion resistance of magnesium alloy. However, with the prolonging of immersion time, the coating corrosion resistance decreases.

Cognitive diagnostic assessment (CDA) intends to identify learners' strengths and weaknesses in latent cognitive attributes to provide personalized remedial instructions. Previous CDA studies on English as a Foreign Language (EFL)/English as a Second Language (ESL) writing have adopted dichotomous cognitive diagnostic models (CDMs) to analyze data from checklists using simple yes/no judgments. Compared to descriptors with multiple levels, descriptors with only yes/no judgments were considered too absolute, potentially resulting in misjudgment of learners' writing ability. However, few studies have used polytomous CDMs to analyze graded response data from rating scales to diagnose writing ability. This study applied polytomous CDMs to diagnose 1166 EFL learners' writing performance scored with a three-level rating scale. The sG-DINA model was selected after comparing model-data fit statistics of multiple polytomous CDMs. The results of classification accuracy indices and item discrimination indices further demonstrated that sG-DINA had good performance on identifying learners' strengths and weaknesses. The generated diagnostic information at group and individual levels was further synthesized into a personalized diagnostic report, although its usefulness still requires further investigation. The findings provided evidence for the feasibility of applying polytomous CDM in EFL writing assessment. [ABSTRACT FROM AUTHOR]

Calcium phosphate (Ca–P) coatings provide an effective approach in current research and the clinical application of Mg alloys by endowing them with improved corrosion resistance, biocompatibility, and even bioactivity. Ca-containing coatings were prepared on AZ31B magnesium alloys using the micro-arc oxidation (MAO) technique and a combination of ethylenediaminetetraacetic acid calcium disodium (EDTA–Ca), calcium glycerophosphate (GP–Ca), calcium gluconate (CaGlu2), and calcium lactate (CaLac2) as the Ca source in a near-neutral solution. The respective and mutual impacts of the four calcium salts on the formation and properties of the coatings were investigated. Experimental results indicated that GP–Ca was more decisive than EDTA–Ca, CaGlu2, and CaLac2 in the formation, morphology, and, therefore, the corrosion resistance of the coatings. GP–Ca alone could not effectively incorporate Ca2+ ions into the coatings but it could combine with EDTA–Ca, CaGlu2, and CaLac2 to bring a synergistic effect in improving the Ca content of the coatings. The bifunctional structure of CaGlu2 and CaLac2, containing hydroxyl groups and carboxylic groups with anchoring effects, enabled them to enhance the Ca content of the coatings. However, due to minor differences in functional group orientation, CaGlu2 was a little more efficient than CaLac2 in increasing Ca content, while CaLac2 was a little more efficient than CaGlu2 in improving the corrosion resistance of the coatings. Finally, the total concentration of the four calcium salts, [Ca2+]T, should be controlled at a proper level; otherwise, excessively high [Ca2+]T would produce localized microbumps originating from coating ablation, eventually deteriorating the corrosion resistance of the coatings. [ABSTRACT FROM AUTHOR]

Suicide among college students, as a subgroup of young people, has received increasing attention in recent years. Exploring the determination of protective and risk factors related to suicide is imperative to understanding the reason for committing suicide and how to take action. We examined loneliness and school belonging as predictors of suicide risk (viz., suicidal behavior and depression) in college students in China by a cross-sectional study. In total, 393 college students participated in the study. The results of hierarchical regression analyses that controlled for age and sex indicated that school belonging buffers the negative effects of loneliness on suicidal behavior and depression. Evidence of a significant loneliness × school belonging interaction as a predictor of both suicidal behavior and depression was found. The present findings show that school belonging represents a positive psychological resource that should be considered in understanding suicide risk among college students in China. More attention should be given to improving the school belonging of college students. [ABSTRACT FROM AUTHOR]