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In this study, the impact of principal stress states on the stress characteristics and initial failure of the rock mass surrounding a three-center arch opening was investigated using complex variable function methods and Discrete Element Method (DEM) numerical modeling. First, the mapping function of the opening was determined using the trigonometric interpolation method, and the influence of the number of terms in the mapping function on its accuracy was revealed. Based on this, the far-field stress state of the underground rock mass was characterized by the ratio of the minimum to maximum principal stress (λ) and the angle (β) between the principal stress and the vertical direction. This stress state was then converted into normal and shear stresses. Using complex variable function theory, the stress characteristics at the boundary of the opening under different stress states were analyzed. Finally, DEM numerical modeling was employed to study the initial failure characteristics at the boundary of the opening and its relationship with the stress distribution. The results indicate that the lateral pressure coefficient significantly affects the stability of the opening by influencing stress concentration around the surrounding rock. Low lateral pressure coefficients lead to tensile stress concentration at the boundary perpendicular to the maximum principal stress. As the coefficient increases, tensile stress decreases, and compressive stress areas expand. While the principal stress direction has a minor effect on stress concentration, it notably impacts stress distribution at the boundary. When λ < 1.0 and β = 45°, stress distribution asymmetry is most pronounced, with the highest compressive stress. The early failure distribution aligns with stress concentration areas, validating the use of stress analysis in predicting opening stability and failure characteristics. [ABSTRACT FROM AUTHOR]

In this study, we introduced the chaos game optimization-artificial neural network (CGO-ANN) model as a novel approach for predicting peak particle velocity (PPV) induced by mine blasting. The CGO-ANN model is compared with other established methods, including the particle swarm optimization-artificial neural network (PSO-ANN), the genetic algorithm-artificial neural network (GA-ANN), single ANN, and the USBM empirical model. The aim is to demonstrate the superiority of the CGO-ANN model for PPV prediction. Utilizing a dataset comprising 180 blasting events from the Tonglushan Copper Mine in China, we investigated the performance of each model. The results showed that the CGO-ANN model outperforms other models in terms of prediction accuracy and robustness. This study highlights the effectiveness of the CGO-ANN model as a promising tool for PPV prediction in mining operations, contributing to safer and more efficient blasting practices. [ABSTRACT FROM AUTHOR]

This letter presents a new filtering technique for interferometric synthetic aperture radar (InSAR) phase images. Traditional local denoising algorithms all suffer from the drawback of removing texture detail information. In contrast, several nonlocal methods have attained good performance in InSAR applications. However, these methods only take radiometric similarity. The patch-based locally optimal Wiener filter (PLOW) utilizes both geometrically and radiometrically similar patch information by clustering analysis and nonlocal filtering; thus, it can better balance between detail preservation and denoising. Nevertheless, PLOW itself is not fitted for InSAR. In this letter, we modify and improve the original algorithm while considering the coherence coefficient and the characteristics of InSAR. This new method provides better filtering results, but with a higher computational cost. Moreover, we introduce the box dimension in fractal geometry as a new index. Experiments on simulated and real data demonstrate that this algorithm outperforms traditional denoising methods. [ABSTRACT FROM PUBLISHER]

High‐throughput sequencing has sparked increased research interest in RNA modifications, particularly tRNA methylation, and its connection to various diseases. However, the precise mechanisms underpinning the development of these diseases remain largely elusive. This review sheds light on the roles of several tRNA methylations (m1A, m3C, m5C, m1G, m2G, m7G, m5U, and Nm) in diverse biological functions, including metabolic processing, stability, protein interactions, and mitochondrial activities. It further outlines diseases linked to aberrant tRNA modifications, related enzymes, and potential underlying mechanisms. Moreover, disruptions in tRNA regulation and abnormalities in tRNA‐derived small RNAs (tsRNAs) contribute to disease pathogenesis, highlighting their potential as biomarkers for disease diagnosis. The review also delves into the exploration of drugs development targeting tRNA methylation enzymes, emphasizing the therapeutic prospects of modulating these processes. Continued research is imperative for a comprehensive comprehension and integration of these molecular mechanisms in disease diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Background: The optimal surgical approach for intermediate-risk papillary thyroid carcinoma (IR-PTC) (according to ATA definition), whether total thyroidectomy (TT) or lobectomy (LT), has remained a contentious clinical gray area for several decades. This systematic review and meta-analysis aim to provide robust evidence and address this clinical dilemma comprehensively., Materials and Methods: A comprehensive literature search was conducted in Pubmed, Embase, Web of Science, and the Cochrane Library from 1st January 2009 to 29th December 2023 to evaluate the impact of different surgical options (TT or LT) on patients with IR-PTC. The primary outcomes included survival, recurrence rates, and postoperative complications. I2 and sensitivity analysis was used to explore the heterogeneity., Results: A total of 8 studies involving 2984 participants were included in this meta-analysis and systematic review. The results indicated that LT was a superior choice for mitigating complications compared to TT [risk ratio (RR), 0.32; 95% CI: 0.24-0.44, P <0.01], particularly for transient complications (RR, 0.24; 95% CI: 0.08-0.65, P <0.01), such as the transient parathyroid dysfunction (RR, 0.04; 95% CI: 0.01-0.15, P <0.01). However, TT did not increase the risk of recurrent laryngeal nerve palsy (RR, 0.78; 95% CI: 0.24-2.47, P =0.67), hemorrhage/seroma (RR, 0.77; 95% CI: 0.48-1.25, P =0.30), and permanent complications (RR, 0.18; 95% CI: 0.02-1.42, P =0.10). Besides, both LT and TT presented similar effect on survival outcomes (overall survival: RR, 1.00; 95% CI: 0.97-1.03, P =0.92, disease-specific survival: RR, 0.99; 95% CI: 0.97-1.02, P =0.69, recurrence-free survival: RR, 1.00; 95% CI: 0.96-1.05, P =0.86), recurrence (RR, 1.05; 95% CI: 0.76-1.46, P =0.76)., Conclusion: The present meta-analysis revealed that TT did not yield improved outcomes in IR-PTC patients, but was associated with an increased incidence of temporary complications. In light of these findings, it may be advisable to consider LT as the optimal choice for IR-PTC patients., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Objective: This study aimed to evaluate the combination of SDF-1 and KLD-12 to form self-assembling polypeptide and its effect on osteogenic differentiation., Methods: ELISA assay was performed to detect whether KLD-12 composite SDF-1 self-assembled polypeptide was successfully prepared. BMSCs were isolated and characterized by Flow cytometry. MTT assays, Calcein-AM/PI fluorescence staining, and Glycosaminoglycans (GAGs) measurement were carried out to detect cell viability after cells exposed to KLD-12 composite SDF-1 selfassembled polypeptide. The migration of cells induced by KLD-12 composite SDF-1 selfassembled polypeptide was also examined by transwell assay and Immunoblot. Osteogenic differentiation of cells stimulated with KLD-12 composite SDF-1 self-assembled polypeptide was analyzed by Immunoblot, Alizarin Red Staining, and Alkaline Phosphatase activity. Additionally, immunoblot and immunofluorescence assays were performed to investigate the effects of the polypeptide on the Wnt/β-catenin pathway., Results: KLD-12 composite SDF-1 self-assembled polypeptide was successfully prepared and identified. In addition, we isolated and characterized mouse mesenchymal stem BMSCs. Our data further revealed that KLD-12 combined with SDF-1 self-assembled polypeptide improved the survival of BMSCs and promoted cell migration. Moreover, the self-assembled polypeptide induced osteogenic differentiation of BMSCs. Mechanically, we found that the self-assembled polypeptide activated the Wnt/β-catenin pathway, therefore promoting the differentiation and migration of BMSCs., Conclusion: Our proposed treatment can potentially be effective for bone defects., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: To investigate the value of the neutrophil-to-lymphocyte ratio (NLR) and Interleukin 18 (IL-18) level in patients with deep vein thrombosis after receiving surgery for spinal degeneration; and we explore their significance in clinical practice., Methods: This study was conducted in 296 patients who were treated in our hospital for spinal degeneration. After surgery, these patients were followed up for 1 month. After performing the color Doppler ultrasound examination, patients were divided into the thrombus group (n = 72) and the non-thrombus group (n = 224) based on the occurrence of deep vein thrombosis. Baseline data, NLR values and IL-18 levels before surgery, and at 1, 3, 5, and 7 days after surgery were compared between the two groups. Logistic regression analysis was implemented to analyze the risk factors for postoperative deep vein thrombosis. Patients in the thrombosis group were allocated to the mild, moderate, and severe group on the basis of the degree of thrombosis. NLR values and IL-18 levels at 3 days after surgery were compared among the three groups. The correlations between both NLR value and IL-18 level and the severity of deep vein thrombosis were analyzed with Pearson correlation. Receiver operating characteristic curve was used to assess the clinical value of NLR value and IL-18 level at 3 days after surgery in predicting postoperative deep vein thrombosis., Results: There were significant differences concerning age, the history of diabetes, and obesity between the two groups (all P<0.05). NLR values and IL-18 levels in both groups after surgery were increased when compared with before surgery (all P<0.01). In addition, NLR values and IL-18 levels reached a peak at 3 days after surgery. Compared with the non-thrombus group, NLR values and IL-18 levels in the thrombus group at 1, 3, 5, and 7 days after surgery were increased (all P<0.01). NLR value and IL-18 level in the thrombosis group at 3 days after surgery were increased with a worsened degree of thrombosis. In other words, both NLR value and IL-18 level were positively correlated with the degree of deep vein thrombosis. The results of logistic regression analysis displayed that age ≥60 years old, body mass index ≥23 kg/m 2 , NLR value >4.34%, and IL-18 level >115.71 ng/mL were independent risk factors for postoperative deep vein thrombosis. The results of the ROC curve showed that the area under curves, which represent the formation of postoperative deep vein thrombosis, were above 0.7 when using NLR value and IL-18 level at 3 days after surgery (both P<0.001)., Conclusion: Compared with the non-thrombus group, NLR value and IL-18 level in the thrombosis group after receiving surgery for spinal degeneration are significantly increased. In addition, the more severe the thrombosis is, the higher the NLR value and IL-18 level at 3 days after surgery. Therefore, NLR value and IL-18 level at 3 days after surgery have certain clinical value in predicting postoperative deep vein thrombosis and prognosis., Competing Interests: None., (AJTR Copyright © 2021.)