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Quantitative evaluation of blasting damage has always been a matter of great concern to the engineering blasting field.In this paper, an active confining pressure and boundary constraint device is designed and developed to solve the problem of boundary constraint in traditional indoor small specimen blasting and punching problem caused by poor sealing effect.Based on CT scan and 3D reconstruction, the method of testing and calculating the rock damage after blasting is proposed.The method can be used to quantitatively evaluate and analyze the degree of damage and fracture after the rock specimen is blasted with small charge.Using the device and the method, the laboratory blasting test of red sand stone of small charge under different relative confining pressure was carried out, the CT scan and CT image binarization processing of the post-explosion specimen was carried out, and the rock specimen was reconstructed based on Mimics 10.01.It is found that the reconstructed model has strong similarity with the real post-explosion specimen.Finally, fractal dimension and damage degree are calculated.The research results provide a new idea for blasting damage evaluation.

Simple Summary: The brown planthopper (Nilaparvata lugens) is a major pest threatening rice crops, especially in Asia and Africa, causing damage and transmitting harmful viruses. Current control strategies, such as the use of chemical pesticides, are becoming increasingly ineffective due to the development of resistance in pest populations. RNA interference (RNAi) is a promising alternative for silencing essential genes in pests. This study focuses on the NlCPSF30 gene (homolog of mammalian CPSF30), which is crucial for mRNA processing in brown planthoppers. By using RNAi to knock down the NlCPSF30 gene, we observed marked reductions in survival rates and notable developmental defects in the pests. These findings highlight the potential of targeting NlCPSF30 for developing RNAi-based pest control strategies. The brown planthopper (Nilaparvata lugens) is a major pest threatening global rice production, significantly reducing yields annually. As N. lugens increasingly develops resistance to conventional control methods, such as chemical pesticides, there is an urgent need for innovative and sustainable pest management strategies. Cleavage and Polyadenylation Specificity Factor 30 (CPSF30) is a key protein involved in mRNA 3′ end processing, yet its function in N. lugens remains poorly understood. This study aims to elucidate the role of CPSF30 in the growth and development of N. lugens and evaluate its potential as a target for RNA interference (RNAi)-based pest control strategies. We cloned and characterized the cDNA sequence of NlCPSF30, which encodes a protein of 341 amino acids containing five CCCH zinc-finger domains and two CCHC zinc-knuckle domains. Sequence alignment revealed that NlCPSF30 is highly conserved among insect species, particularly in the zinc-finger domains essential for RNA binding and processing. Phylogenetic analysis showed that NlCPSF30 is closely related to CPSF30 proteins from other hemipteran species. Expression analysis indicated that NlCPSF30 is most highly expressed in the fat body and during the adult stage, with significantly higher expression in females than in males. RNAi-mediated silencing of NlCPSF30 in third-instar nymphs resulted in severe phenotypic abnormalities, including disrupted molting and increased mortality following injection of double-stranded RNA (dsRNA) targeting NlCPSF30. Moreover, it influenced the expression of genes associated with hormone regulation, namely NlHry, NlE93, and NlKr-h1. These results suggest that NlCPSF30 is integral to critical physiological processes, with its disruption leading to increased mortality. Our findings identify NlCPSF30 as an essential gene for N. lugens' survival and a promising target for RNAi-based pest management strategies. This study provides a valuable molecular target and theoretical insights for developing RNAi-based control methods against N. lugens. [ABSTRACT FROM AUTHOR]

Simple Summary: The brown planthopper is a major pest threatening rice crops in Asia, making it essential to identify target genes for RNAi-based pest control strategies. The Cleavage Stimulation Factor (CstF) complex, which plays a key role in mRNA 3′ end processing, is composed of several critical genes, and mutations in these genes can cause severe developmental defects, indicating their potential as targets. In this study, we identified homologs of the human CstF complex genes (NlCstF50, NlCstF64, and NlCstF77) in Nilaparvata lugens and investigated their functions using RNAi techniques. These genes are expressed throughout all developmental stages and various tissues, with particularly high levels in eggs and testes. Targeting these genes with RNAi resulted in significant mortality, decreased egg production, and lower hatch rates. These results suggest that NlCstF50, NlCstF64, and NlCstF77 could be effective targets for RNAi-based pest control strategies. The Cleavage Stimulation Factor (CstF) complex, consisting of three subunits, is essential for the 3′ end processing of precursor messenger RNA (pre-mRNA). In mammals, this complex includes CstF50, CstF64, and CstF77, named according to their molecular weights, and these proteins are conserved across many organisms. However, the functional roles of the three CstF genes (NlCstF50, NlCstF64, and NlCstF77) in Nilaparvata lugens, a major rice pest, have not been fully explored. This study identified and characterized the sequences of these genes, with proteins encoded by NlCstF50, NlCstF64, and NlCstF77 consisting of 439, 419, and 732 amino acids, respectively. These proteins are conserved among various insect species. Spatio-temporal expression analysis revealed that these genes are expressed at all developmental stages and in various tissues, with peak levels in eggs and testes. RNA interference (RNAi) targeting one or all three NlCstF genes resulted in a reduction in gene expression by 68% to 90% at 72 h post-injection, indicating that multi-gene dsRNA can achieve similar silencing outcomes as single-gene dsRNA. Knocking down one or all three NlCstF genes caused significant lethal phenotypes and molting disruptions. Mortality rates increased from 62.5% (dsNlCstF50) to 95.4% (dsNlCstF(50+64+77)). Additionally, silencing these genes reduced the number of eggs laid per female and hatch rates. These results highlight the critical role of NlCstF genes in the development and reproduction of N. lugens, suggesting their potential as targets for RNAi-based pest control strategies. [ABSTRACT FROM AUTHOR]

The main challenge for immune checkpoint blockade (ICB) therapy lies in immunosuppressive tumor microenvironment (TME). Repolarizing M2‐like tumor‐associated macrophages (TAMs) into inflammatory M1 phenotype is a promising strategy for cancer immunotherapy. Here, this study shows that the tumor suppressive protein SHISA3 regulates the antitumor functions of TAMs. Local delivery of mRNA encoding Shisa3 enables cancer immunotherapy by reprogramming TAMs toward an antitumoral phenotype, thus enhancing the efficacy of programmed cell death 1 (PD‐1) antibody. Enforced expression of Shisa3 in TAMs increases their phagocytosis and antigen presentation abilities and promotes CD8+ T cell‐mediated antitumor immunity. The expression of SHISA3 is induced by damage/pathogen‐associated molecular patterns (DAMPs/PAMPs) in macrophages via nuclear factor‐κB (NF‐κB) transcription factors. Reciprocally, SHISA3 forms a complex with heat shock protein family A member 8 (HSPA8) to activate NF‐κB signaling thus maintaining M1 polarization of macrophages. Knockout Shisa3 largely abolishes the antitumor efficacy of combination immunotherapy with Toll‐like receptor 4 (TLR4) agonist monophosphoryl lipid A (MPLA) and PD‐1 antibody. It further found that higher expression of SHISA3 in antitumoral TAMs is associated with better overall survival in lung cancer patients. Taken together, the findings describe the role of SHISA3 in reprogramming TAMs that ameliorate cancer immunotherapy. [ABSTRACT FROM AUTHOR]

In this study, the effects of preloaded uniaxial compressive stress and defect (prefabricated by laser cutting) curvature on blast-induced cracks and stress wave propagation were investigated in polymethyl methacrylate (PMMA) specimens using caustics theory. Based on the mathematical relationship between stress and optics, the fracture behavior (the propagation path, dynamic stress intensity factors (DSIFs), propagation velocity, initiation angle of the main crack, and damage degree between the defect and the blasthole) was calculated and analyzed quantitatively. The results show that the preloaded stress could mainly restrain the main crack propagation in the horizontal direction and reduce the initiation angle and damage degree at the defects. Meanwhile, the crack initiation position of the positive curvature defect was not at the end of the defect. In addition, the curvature of the defect significantly affected the blast-induced fracture compared to preloaded stresses. Comparing the main crack with other curvature defects, the DSIFs, velocity, crack arrest time, crack length, and horizontal offset distance of the main crack with negative curvature defect were the largest. The variation in the full stress field in the specimen under blasting and preloaded stress was simulated by a numerical model. The results show that the curvature of the defect has a significant effect on tensile waves at the end of defects, and the tensile stress from high to low was C-25, C0, and C25, in that order. [ABSTRACT FROM AUTHOR]