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Objective To explore the feasibility and rationality of advanced integrated two-stage laparoscopic simulation training course in standardized training of surgical residents. Methods From December 2019 to December 2021, the advanced integrated two-stage laparoscopic simulation training course was carried out among 2019—2020 surgical residents who received standardized training in our hospital. The course was divided into two stages. In the first stage, BEST (best essential surgical technology training) course, adopted Darwin® endoscopic training system, Tianyan® endoscopic training system, Microport® 3D laparoscopic training system and simple simulative models were used. The second stage, BEST PLUS course, same platform as that in BEST course and in vitro animal models were used. The questionnaire survey method (before and after class questionnaire) was adopted to evaluate the curriculum setting, such as curriculum form, simulators, teaching method, time arrangement, curriculum difficulty, training effect, curriculum satisfaction and so on. Results A total of 37 surgical residents completed the two-stage course training and the questionnaire survey. The overall satisfaction rate with the curriculum setting was 100%. There were 32 residents (86.5%) thought that first stage training course could significantly improve their clinical skills, 35 residents (94.6%) thought that second stage training course could significantly improve their clinical skills, and 36 resident (97.3%) thought that the first stage curriculum could significantly help them improve performance in the second stage curriculum. Conclusions The trainees had a high degree of recognition and satisfaction for the advanced integrated two-stage laparoscopic simulation training course. The overall design of course was reasonable and feasible, and was attractive to trainees.

Background The 'Learn, See, Practice, Prove, Do, Maintain' (LSPPDM) pedagogical framework is an evidence-based framework developed through a careful review and synthesis of the literature. The purpose of the study was to explore the effectiveness and applicability of the LSPPDM pedagogical framework in the laparoscopic training course for surgical residents. Methods Prospective study of surgical residents who underwent standardized surgical residency training in a single institution from December 2020 to December 2022. Trainees were randomized to either the pedagogical group (6-step LSPPDM pedagogical framework) or traditional group (2-step traditional approach with twice-weekly lectures and a weekly laparoscopic operating skills session). The Global Operative Assessment of Laparoscopic Skills scale was used for technical skills, and the Non-Technical Skills for Surgeons assessment form was used for non-technical skills. Results Sixty trainees were randomized. The pedagogical group scored higher on subjective perception (P < 0.050) and the theoretical assessment (mean(s.d.) 41.83(6.66)) than those in the traditional group (37.83(5.77)) (P = 0.016). Trainees in the pedagogical group took less time to complete the assessment of models, had fewer failures and higher scores, took less time to complete laparoscopic sutures and knots, showed better proficiency with laparoscopic instruments, and completed at higher quality (P < 0.050). Trainees performing laparoscopic cholecystectomy in animal models demonstrated higher technical and non-technical skill scores in the pedagogical group (P < 0.050). 'Tissue handling' and 'Decision making' were common areas for improvement for both groups of trainees. Conclusions The LSPPDM pedagogical framework is feasible and demonstrated improvements in technical and non-technical skills in surgical trainees compared to a traditional training programme. [ABSTRACT FROM AUTHOR]

Models that predict tool life based on wear mechanism knowledge are typically inaccurate, as the use of simplified model parameters can have a significant effect on this prediction. While a tool life prediction model based on sample cutting data is limited to specific working conditions, which makes tool life prediction difficult to generalize, and needs a large amount of historical data as support. In this paper, the empirical formula of tool life based on wear mechanism knowledge was combined with a neural network, which can significantly improve prediction accuracy. Firstly, a concept of tool life grade is proposed, and its classification standard is outlined. Secondly, a prediction model based on the empirical life formula and experimental data was established. Thirdly, a tool wear prediction model based on a convolutional neural network (CNN) was established through the real-time tool condition data, and the corresponding life compensation strategy can be determined by comparing this with the historical data. Finally, the empirical life grade was adjusted to obtain the real-time tool life grade. A case example shows that the data-driven knowledge-guided prediction model can significantly improve the recognition accuracy of tool life grade. [ABSTRACT FROM AUTHOR]

The radioactive particle chain is a linear array of 125I particles and placed in a tubular conduit. The dose distribution of the particle chain is similar to the shape of a cylinder. It may be adapted to the tumors in the lumen and exerts the radiotherapy effect that may not be achieved by single particles. This article aims to review the history of 125I radioactive particle chains, dose distribution, placement methods and clinical application.

Objectives: To evaluate the safety and effectiveness of computed tomography (CT)-guided radioactive 125I seeds brachytherapy (RISB) for lung oligometastases (LO) from colorectal cancer (CRC). Methods: Data for 144 LOs from 70 CRC patients who underwent CT-guided RISB were retrospectively analyzed. The primary endpoints were progression-free survival (PFS) and overall survival (OS), and the secondary endpoints were technical success, local control rate (LCR), and complications. Kaplan–Meier method was used for survival analysis. Cox model was used to identify the independent predictors of poor prognosis. Results: The RISB procedures were successfully performed in all patients, and the success rate was 100%. The median follow-up was 27.8 months. The median PFS was 10.0 months (95% CI: 8.9–11.1) and the 1- and 2-year PFS rates were 32.9% and 5.9%, respectively. On multivariate analysis, serum carcinoembryonic antigen (CEA) ≤ 15 ng/ml (P = 0.048), middle-high differentiated pathological classification (P = 0.015), primary TNM stages I-III (P = 0.001), LO number ≤ 2 (P < 0.001) and cumulative gross tumor volume (GTV) ≤ 40 cm3 (P < 0.001) showed superior PFS. The median OS was 30.8 months (95% CI: 27.1–34.4) and the 1-, 2-, and 3-year OS rates were 95.7%, 67.4%, and 42.5%, respectively. On multivariate analysis, serum CEA ≤ 15 ng/ml (P = 0.004), middle-high differentiated pathological classification (P < 0.001), primary TNM stages I-III (P < 0.001), LO number ≤ 2 (P < 0.001), cumulative GTV ≤ 40 cm3 (P < 0.001) and system treatments combined with chemotherapy and target therapy (P < 0.001) showed superior OS. The LCR for 3, 6, and 12 months was 97.9%, 91.0%, and 83.6%, respectively. There were 4 cases of pneumothorax at 5.7% that required drainage. Conclusions: RISB for LO from CRC is safe and effective, and serum CEA, TNM stage, LO number, cumulative GTV, and system treatments should be emphasized for long OS. Key points: • CT-guided RISB is a new treatment for lung oligometastases from CRC. • RISB can be an alternative therapy for patients who are unsuitable for surgery, ablation, or SBRT. • Serum CEA, TNM stage, LO number, cumulative GTV, and system treatments are prognostic factors. • RISB is a safe method with a curative effect. [ABSTRACT FROM AUTHOR]

The conditions of cutting tool wear in the machining process have a great influence on the dimension accuracy and surface integrity of a workpiece. Real-time tool condition monitoring can alert a worker to changes in a tool in time before tool failure occurs to reduce downtime and improve product quality. However, traditional monitoring methods are no longer able to meet the requirements of real-time monitoring in current intelligent manufacturing. Therefore, an online monitoring method based on deep learning to monitor the cutting tool conditions is proposed In this research. In this monitoring model, one-dimensional wide-kernel convolution is used to filter the high-frequency noise in the multi-dimensional raw signals, and then a deep residual convolution layer is adopted to adaptively extract the multi-dimensional spatial features of the signals, and a gated recurrent unit (GRU) layer with an attention mechanism is employed to adaptively extract the hidden temporal features of the sequence data and adaptively assign the corresponding weights, and finally, a regression layer is used to predict the wear value of the tool according to the extracted features. The PHM 2010 challenge dataset is used to illustrate and evaluate this proposed method. The experiment results show that the proposed method can accurately predict the future flank wear values in real time based on the acquired multi-dimensional signals and avoid the complexity of the manual feature extraction. [ABSTRACT FROM AUTHOR]

High‐cutting performance is an essential metric for improving the suitability of materials for industrial applications. Herein, the machining properties of stone‐plastic composite are assessed through a finite element method to explore orthogonal cutting behavior by diamond cutters. The key aspects examined in this work are the effects of tool geometry and cutting parameters on the cutting force, temperature, chip formation, von Mises stress, and surface quality finish. Primary findings show that chip continuity increases proportionally with increase in rake angle but decreases with cutting speed and depth. Meanwhile, both cutting stability and surface quality are negatively correlated with cutting speed and depth but positively correlated with rake angle. These results support the adoption of cutting conditions using greater rake angle, higher cutting speed, and shallower cutting depth to obtain higher cutting performance, that is, greater cutting stability and surface quality in the finishing machining of stone‐plastic composites. [ABSTRACT FROM AUTHOR]

Immune checkpoint inhibitors (ICIs) targeting PD-1 or PD-L1 have emerged as a revolutionary treatment strategy for human cancer patients. However, as the response rate to ICI therapy varies widely among different types of tumours, we are beginning to gain insight into the mechanisms as well as biomarkers of therapeutic response and resistance. Numerous studies have highlighted the dominant role of cytotoxic T cells in determining the treatment response to ICIs. Empowered by recent technical advances, such as single-cell sequencing, tumour-infiltrating B cells have been identified as a key regulator in several solid tumours by affecting tumour progression and the response to ICIs. In the current review, we summarized recent advances regarding the role and underlying mechanisms of B cells in human cancer and therapy. Some studies have shown that B-cell abundance in cancer is positively associated with favourable clinical outcomes, while others have indicated that they are tumour-promoting, implying that the biological function of B cells is a complex landscape. The molecular mechanisms involved multiple aspects of the functions of B cells, including the activation of CD8+ T cells, the secretion of antibodies and cytokines, and the facilitation of the antigen presentation process. In addition, other crucial mechanisms, such as the functions of regulatory B cells (Bregs) and plasma cells, are discussed. Here, by summarizing the advances and dilemmas of recent studies, we depicted the current landscape of B cells in cancers and paved the way for future research in this field. [ABSTRACT FROM AUTHOR]

Background: Myocardial ischemia/reperfusion injury is associated with adverse cardiovascular outcomes after acute myocardial infarction. However, the molecular mechanism of ischemia/reperfusion injury remains unclear. Mitochondria dysfunction is a participant in and regulator of myocardial ischemia-reperfusion injury. However, the molecular mechanisms involved in this process are not yet fully understood. We previously reported that Notch1 can reduce mitochondrial lysis, reduce myocardial infarct size, and inhibit ventricular remodeling. Herein, we explore the role of the downstream target Notch1 in mitochondrial regulation. Methods: This study constructs an ischemic/reperfusion injury rat model and a hypoxia/reoxygenation cell model. The expression of PTEN is detected by real-time PCR, Western blot, and immunofluorescence staining. Cell viability is analyzed with CCK-8. Apoptosis level is detected via the TUNEL assay, and mitochondrial fission/fusion is analyzed with MitoTracker Green staining. Cardiac troponin I (cTnI), lactate dehydrogenase (LDH), superoxide dismutase (SOD), and CK levels of creatine kinase-MB (CK) are measured with ELISA kits. Results: We found that PETN-Pink1-Parkin signaling is inhibited by Notch1 I/R in injured neonatal cardiomyocytes and hearts, i.e., via the inhibition of mitochondrial dysfunction and fragmentation. With the recure of PTEN or Pink1, the protective effect of Notch1 was largely diminished. Conclusion: These results suggest that N1ICD acts protectively against ischemic reperfusion injury by suppressing PTEN-Pink1-mediated mitochondrial dysfunction and fragmentation. [ABSTRACT FROM AUTHOR]

Ischemic preconditioning (IPC), and ischemic postconditioning (IPost) have a significant protective effect on myocardial ischemia/reperfusion (MI/R) injury by alleviating oxidative stress and mitochondrial disturbances, although the underlying molecular mechanisms are unclear. The study was to demonstrate that cardioprotection against anoxia/reoxygenation (A/R) injury is transduced via the Notch1/Hes1/VDAC1 signaling pathway. Using mass spectrometry and tandem affinity purification (TAP), to screen for differentially expressed proteins associated with Hes1, followed by standard bioinformatics analysis. The co‐immunoprecipitation (Co‐IP) assay confirmed an interaction between Hes1 and VDAC1 proteins. H9c2 cells were transfected with Hes1 adenoviral N‐terminal TAP vector (AD‐NTAP/Hes1) and Hes1‐short hairpin RNA adenoviral vector (AD‐Hes1‐shRNA) to establish A/R injury, IPC, and IPost models, respectively. The expression of Hes1 and VDAC1 proteins were measured by western blot analysis, while the levels of reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), and apoptosis were evaluated by flow cytometry. AD‐NTAP/Hes1 can activate the exogenous protein expression of Hes1, thus decreasing creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) activity and promoting cell viability. The study found that VDAC1 was a potential target protein for Hes1 and the overexpression of Hes1 protein expression downregulated protein expression levels of VDAC1, reduced ROS production, stabilized ΔΨm, and inhibited apoptosis in H9c2 cells. Additionally, downregulation of Hes1 protein expression also upregulated VDAC1 protein expression, increased ROS production, imbalanced ΔΨm, promoted cell apoptosis, and attenuated the cardioprotection afforded by IPC and IPost. The Notch1/Hes1 signaling pathway activated by IPC/IPost can directly downregulate the protein expression of VDAC1 and consequently relieve A/R injury. [ABSTRACT FROM AUTHOR]

Traditional welding quality inspection methods for pipelines and pressure vessels are time-consuming, labor-intensive, and suffer from false and missed inspection problems. With the development of smart manufacturing, there is a need for fast and accurate in-situ inspection of welding quality. Therefore, detection models with higher accuracy and lower computational complexity are required for technical support. Based on that, an in-situ weld surface defect recognition method is proposed in this paper based on an improved lightweight MobileNetV2 algorithm. It builds a defect classification model with MobileNetV2 as the backbone of the network, embeds a Convolutional Block Attention Module (CBAM) to refine the image feature information, and reduces the network width factor to cut down the number of model parameters and computational complexity. The experimental results show that the proposed weld surface defect recognition method has advantages in both recognition accuracy and computational efficiency. In summary, the method in this paper overcomes the limitations of traditional methods and achieves the goal of reducing labor intensity, saving time, and improving accuracy. It meets the actual needs of in-situ weld surface defect recognition for pipelines, pressure vessels, and other industrial complex products. [ABSTRACT FROM AUTHOR]

The hallmark feature of Diabetes mellitus (DM) is hyperglycemia which can lead to excess production of reactive oxygen species (ROS) in the myocardium, contributing to diabetic cardiomyopathy (DCM). Nuclear factor erythroid2‐related factor2 (Nrf2), a transcriptional activator, enhances its ability to resist oxidative stress by activating multiple downstream anti‐oxidants, anti‐inflammatory proteins, and detoxifying enzymes. However, the mechanism of Nrf2 signaling in HG‐induced DCM is unclear. In this study, we used HG pretreated H9c2 cells as the experimental basis in vitro, and established a high fat‐diet, streptozotocin (STZ) induced Type 2 diabetic rat model in vivo. Meanwhile, we used shRNA‐Nrf2 and curcumin (CUR) (as an activator) to affect H9c2 cells, to verify the role of the Nrf2 signaling pathway in DCM. The results showed that the excessive production of ROS caused by HG, which could inhibit the activation of Nrf2‐related signaling, resulting in a decrease in cell energy metabolism and an increase in cell apoptosis. Surprisingly, we found that the activation of the Nrf2 signaling pathway significantly increased cardiomyocyte viability, reduced ROS formation, increased antioxidant enzyme activity, and inhibited cardiomyocyte apoptosis. In conclusion, these findings conclusively infer that CUR activation of the Nrf2/HO‐1 signaling pathway exerts myocardial protection by reducing ROS formation. [ABSTRACT FROM AUTHOR]