Characteristics of Penetration Strength and Fracture Features under Nonuniform Stress Field around Borehole Surrounding Rock.

In the process of mining coal energy, the excavation of roadways and drilling causes the formation of a nonuniform stress field around the penetration holes, which will lead to a significant concentration of stress around the penetration hole. It even leads to the destruction of the surrounding rock of the penetration hole, affecting the integrity of the surrounding rock of the penetration hole. It has an effect on the strength of the rock obtained by the borehole penetration methods. Based on Abaqus software, the numerical model of borehole penetration was constructed by embedding cohesion elements between solid elements. After analyzing the simulation results obtained under different stress boundaries and penetration directions, the following findings are obtained. (1) Using the occurrence of cracks in the borehole surrounding rock as the criterion, the rock is categorized into either an elastic stress state or a plastic stress state after applying different stress boundary conditions. (2) When the borehole surrounding rock is in the elastic (plastic) stress state, the penetration strength increases (decreases) with the increase of lateral pressure coefficient. (3) In the elastic stress state, borehole surrounding rock's fracture area and crack penetration depth increase (decrease) with the increase of lateral pressure coefficient when the penetration direction is parallel (perpendicular) to the maximum principal stress. In the plastic stress state, the fracture area increases, while crack penetration depth decreases with higher lateral pressure coefficient.

Hybrid Ginseng-derived Extracellular Vesicles-Like Particles with Autologous Tumor Cell Membrane for Personalized Vaccination to Inhibit Tumor Recurrence and Metastasis.

Personalized cancer vaccines based on resected tumors from patients is promising to address tumor heterogeneity to inhibit tumor recurrence or metastasis. However, it remains challenge to elicit immune activation due to the weak immunogenicity of autologous tumor antigens. Here, a hybrid membrane cancer vaccine is successfully constructed by membrane fusion to enhance adaptive immune response and amplify personalized immunotherapy, which formed a codelivery system for autologous tumor antigens and immune adjuvants. Briefly, the functional hybrid vesicles (HM-NPs) are formed by hybridizing ginseng-derived extracellular vesicles-like particles (G-EVLPs) with the membrane originated from the resected autologous tumors. The introduction of G-EVLPs can enhance the phagocytosis of autologous tumor antigens by dendritic cells (DCs) and facilitate DCs maturation through TLR4, ultimately activating tumor-specific cytotoxic T lymphocytes (CTLs). HM-NPs can indeed strengthen specific immune responses to suppress tumors recurrence and metastasis including subcutaneous tumors and orthotopic tumors. Furthermore, a long-term immune protection can be obtained after vaccinating with HM-NPs, and prolonging the survival of animals. Overall, this personalized hybrid autologous tumor vaccine based on G-EVLPs provides the possibility of mitigating tumor recurrence and metastasis after surgery while maintaining good biocompatibility.

Effect of different fertilization strategies on the yield, quality of Euryales Semen and soil microbial community.

Introduction: Euryales Semen, a medicinal herb widely utilized in Asia, faces a critical constraint in its production, primarily attributed to fertilizer utilization. Understanding the impact of different fertilization schemes on Euryales Semen (ES) planting and exploring the supporting mechanism are crucial for achieving high yield and sustainable development of the ES planting industry. Methods: In this study, a field plot experiment was conducted to evaluate the effects of four different fertilization treatments on the yield and quality of ES using morphological characteristics and metabolomic changes. These treatments included a control group and three groups with different organic fertilizer to chemical fertilizer ratios (3:7, 5:5, and 7:3). The results of this study revealed the mechanisms underlying the effect of the different treatments on the yield and quality of Euryales Semen. These insights were achieved through analyses of soil physicochemical properties, soil enzyme activity, and soil microbial structure. Results: We found that the quality and yield of ES were the best at a ratio of organic fertilizer to chemical fertilizer of 7:3. The optimality of this treatment was reflected in the yield, soil available nitrogen, soil available phosphorus, and soil enzyme activity of ES. This ratio also increased soil microbial diversity, resulting in an increase and decrease in Proteobacteria and Firmicutes abundances, respectively. In addition, linear discriminant analysis showed that Chloroflexi, Gammaproteobacteria, and Hypocreales-incertae-sedis were significantly enriched in the ratio of organic fertilizer to chemical fertilizer of 7:3. Variance partitioning analysis showed that the soil properties, enzyme activities, and their interactions cumulatively can explain 90.80% of the differences in Euryales Semen yield and metabolome. In general, blending organic and chemical fertilizers at a 7:3 ratio can enhance soil fertility, boost Euryales Semen yield and quality, and bring forth conditions that are agriculturally beneficial to microbial (bacteria and fungi) dynamics. Discussion: This study initially revealed the scientific connotation of the effects of different fertilization patterns on the planting of Euryales Semen and laid a theoretical foundation for the study of green planting patterns of Euryales Semen with high quality and yield.

Dysregulation of Innate and Adaptive Immune Responses in Asymptomatic SARS-CoV-2 Infection with Delayed Viral Clearance.

Asymptomatic infection with SARS-CoV-2 is a major concern in the control of the COVID-19 pandemic. Many questions concerning asymptomatic infection remain to be answered, for example, what are the differences in infectivity and the immune response between asymptomatic and symptomatic infections? In this study, based on a cohort established by the Wuchang District Health Bureau of Wuhan in the early stage of the COVID-19 pandemic in Wuhan in 2019, we conducted a comprehensive analysis of the clinical, virological, immunological, and epidemiological data of asymptomatic infections. The major findings of this study included: 1) the asymptomatic cohort enrolled this study exhibited low-grade but recurrent activity of viral replication; 2) despite a lack of overt clinical symptoms, asymptomatic infections exhibited ongoing innate and adaptive immune responses; 3) however, the immune response from asymptomatic infections was not activated adequately, which may lead to delayed viral clearance. Given the fragile equilibrium between viral infection and host immunity, and the delayed viral clearance in asymptomatic individuals, close viral monitoring should be scheduled, and therapeutic intervention may be needed.

[BIOCOMPATIBILITY OF POLY-LACTIDE-CO-GLYCOLIDE/COLLAGEN TYPE I SCAFFOLD WITH RAT VAGINAL EPITHELIAL CELLS].

OBJECTIVE: To explore the biocompatibility of the poly-lactide-co-glycolide (PLGA)/collagen type I scaffold with rat vaginal epithelial cells, and the feasibility of using PLGA/collagen type I as scaffold to reconstruct vagina by the tissue engineering. METHODS: PLGA/collagen type I scaffold was prepared with PLGA covered polylysine and collagen type I. The vaginal epithelial cells of Sprague Dawley rat of 10-12 weeks old were cultured by enzyme digestion method. The vaginal epithelial cells of passage 2 were cultured in the leaching liquor of scaffold for 48 hours to detect its cytotoxicity by MTT. The vaginal epithelial cells were inoculated on the PLGA/collagen type I scaffold (experimental group) and PLGA scaffold (control group) to calculate the cell adhesion rate. Epithelial cells-scaffold complexes were implanted subcutaneously on the rat back. At 2, 4, and 8 weeks after implantation, the epithelial cells-scaffold complexes were harvested to observe the cell growth by HE staining and immunohistochemical analysis. The epithelial cells-scaffold complexes were transplanted to reconstruct vagina in 6 rats with vaginal defect. After 3 and 6 months, the vaginal length was measured and the appearance was observed. The neovagina tissues were harvested for histological evaluation after 6 months. RESULTS: The epithelial cells grew and proliferated well in the leaching liquor of PLGA/collagen type I scaffold, and the cytotoxicity was at grade 1. The cell adhesion rate on the PLGA/collagen type I scaffold was 71.8%±9.2%, which significantly higher than that on the PLGA scaffold (63.4%±5.7%) (t=2.195, P=0.005). The epithelial cells could grow and adhere to the PLGA/collagen type I scaffolds. At 2 weeks after implanted subcutaneously, the epithelial cells grew and proliferated in the pores of scaffolds, and the fibroblasts were observed. At 4 weeks, 1-3 layers epithelium formed on the surface of scaffold. At 8 weeks, the epithelial cells increased and arranged regularly, which formed the membrane-like layer on the scaffold. The keratin expression of the epithelium was positive. At 3 months after transplantation in situ, the vaginal mucosa showed pink and lustrous epithelialization, and the majority of scaffold degraded. After 6 months, the neovagina length was 1.2 cm, without obvious stenosis; the vaginal mucosa had similar appearance and epithelial layer to normal vagina, but it had less duplicature; there were nail-like processes in the basal layer, but the number was less than that of normal vagina. The immunohistochemistry staining for keratin was positive. CONCLUSION: The PLGA/collagen type I scaffolds have good cytocompatibility with the epithelial cells, and can be used as the biodegradable polymer scaffold of the vaginal tissue engineering.