Study on the Mechanical Properties of 3D-Printed Sand Mold Specimens with Complex Hollow Structures.

Casting, as a fundamental process in metal forming, finds widespread applications in the manufacturing industry. The advent of 3D printing hollow sand mold technology presents a novel method for casting technology to revolutionize traditional dense sand molds, offering increased flexibility in achieving quality control and improvement in casting processes. Consequently, this study delves into an examination of the mechanical strengths of 3D-printed sand molds with complex hollow structures and further investigates the influence of hollow sand mold concession on castings. The results indicate that compressive and high-temperature residual tensile and bending strengths vary in hollow structures. Multi-layer shells have greater high-temperature residual tensile, compressive, and bending strengths than truss hollow sand molds with roughly the same hollow volume fraction. Compared to dense sand molds, hollow sand molds, which have a lower mechanical strength, have better retractability, which helps reduce the residual stress and crack tendency of castings. The breaking of hollow structures is limited to local areas, unlike the penetrative cracking of dense sand molds. The I-beam-shaped casting test results indicate that a hollow structure is beneficial for the preservation of the integrity of a sand mold during the casting process. Compared to dense and truss hollow molds, a multi-layer shell hollow sand structure has the comprehensive advantages that it improves retractability while maintaining strength relatively well, reduces the residual stress, and avoids cracks in castings and itself.

Simultaneous catalytic oxidation of toluene and CO over Cu-V/Al-Ce catalysts: Physicochemical properties-activity relationship and simultaneous oxidation mechanism.

Cu-V/Al-Ce with varying ratios of Al2O3/CeO2 were prepared to study the simultaneous catalytic oxidation of toluene and CO. Experimental results show that Cu-V/20Al-80Ce exhibits optimal simultaneous oxidation activity and good durability. This superior performance is related to Cu-Ce, V-Ce, and Al-Ce interactions, which facilitate the exposure of active centers, the creation of oxygen vacanicies, and efficient electron transfer. The mutual influence between toluene and CO during the simultaneous oxidation is then demonstrated. Toluene hinders CO oxidation through the competitive adsorption and the consumption of reactive oxygen species. CO enhances toluene oxidation, which is comprehensively explained by affecting the competition between the desorption and oxidation of benzaldehyde. Despite the mutual influence between toluene and CO, the pathways of CO and toluene oxidation are mutually independent. Toluene oxidation proceeds sequentially from toluene to benzyl alcohol, benzaldehyde, benzoate, and finally to CO2. Before being completely oxidized to CO2, CO is initially converted to carboxylic acid, hydrogen carbonate, free carbonate ion, bidentate formate, and monodentate carbonate.

Trends in survival of ovarian clear cell carcinoma patients from 2000 to 2015.

Purpose: To analyze changes in survival outcomes in patients with ovarian clear cell carcinoma (OCCC) treated consecutively over a 16-year period using a population-based cohort. Methods: We conducted a retrospective analysis of OCCC from 2000 to 2015 using data from the Surveillance, Epidemiology, and End Results (SEER) program. The ovarian cancer-specific survival (OCSS) and overall survival (OS) were analyzed according to the year of diagnosis. Joinpoint Regression Program, Kaplan-Meier analysis, and multivariate Cox regression analyses were used for statistical analysis. Results: We included 4257 patients in the analysis. The analysis of annual percentage change in OCSS (P=0.014) and OS (P=0.006) showed that patients diagnosed in later years had significantly better outcomes compared to those diagnosed in early years. The results of the multivariate Cox regression analyses showed that the year of diagnosis was the independent prognostic factor associated with OCSS (P=0.004) and had a borderline effect on OS (P=0.060). Regarding the SEER staging, the OCSS (P=0.017) and OS (P=0.004) of patients with distant stage showed a significant trend toward increased, while no significant trends were found in the survival of patients with localized or regional stage diseases. Similar trends were found in those aged <65 years or those treated with surgery and chemotherapy. However, no statistically significant changes in the survival rate were found in those aged ≥65 years or those receiving surgery alone regardless of SEER stage during the study period. Conclusions: Our study observed a significant increase in the survival outcomes in OCCC from 2000 to 2015, and patients aged <65 years and those with distant stage experienced a greater improvement in survival.

SUMOylation of GMFB regulates its stability and function in retinal pigment epithelial cells under hyperglycemia.

BACKGROUND: Glia maturation factor beta (GMFB) is a growth and differentiation factor that acts as an intracellular regulator of signal transduction pathways. The small ubiquitin-related modifier (SUMO) modification, SUMOylation, is a posttranslational modification (PTM) that plays a key role in protein subcellular localization, stability, transcription, and enzymatic activity. Recent studies have highlighted the importance of SUMOylation in the inflammation and progression of numerous diseases. However, the relationship between GMFB and SUMOylation is unclear. RESULTS: Here, we report for the first time that GMFB and SUMO1 are markedly increased in retinal pigment epithelial (RPE) cells at the early stage of diabetes mellitus (DM) under hyperglycemia. The GMFΒ protein could be mono-SUMOylated by SUMO1 at the K20, K35, K58 or K97 sites. SUMOylation of GMFB led to its increased protein stability and subcellular translocation. Furthermore, deSUMOylation of GMFΒ downregulates multiple signaling pathways, including the Jak-STAT signaling pathway, p38 pathway and NF-kappa B signaling pathway. CONCLUSIONS: This work provides novel insight into the role of SUMOylated GMFB in RPE cells and provides a novel therapeutic target for diabetic retinopathy (DR).

RIPK4 Promotes Cell Invasion and the Epithelial-Mesenchymal Transition in Ovarian Cancer.

OBJECTIVE: To investigate the clinical role and biological function of receptor-interacting protein kinase 4 (RIPK4) in ovarian cancer (OC). METHODS: We conducted a comprehensive analysis of the expression and prognostic role of RIPK4 in OC using various public databases including The Cancer Genome Atlas, Oncomine, and Kaplan-Meier plotter. In vitro studies included wound healing, cell migration and invasion, cell proliferation, and cell apoptosis assays as well as vascular mimicry experiments. In vivo studies were conducted using subcutaneous and intraperitoneal xenografts. RESULTS: Our findings revealed that RIPK4 was significantly overexpressed in OC tissue compared to normal ovarian tissue. Moreover, the overexpression of RIPK4 was associated with advanced-stage disease and a poor prognosis in OC patients. RIPK4 silencing resulted in significant inhibition of intraperitoneal tumor growth, invasion, and vascular mimicry in OC cells. Furthermore, downregulation of RIPK4 inhibited the epithelial-mesenchymal transition of OC cells both in vitro and in vivo by promoting the expression of E-cadherin and inhibiting the expression of N-cadherin. CONCLUSION: The results of this study suggest that RIPK4 may function as an oncogene in the development and prognosis of OC.