6 research outputs found
Vitamin D improves autoimmune diseases by inhibiting Wnt signaling pathway
Abstract Objective In this study, we investigated the development of the Wnt signaling pathway in vitamin D (VitD) to improve systemic lupus erythematosus in mice to breakthrough clinical treatment approaches. Methods Body weight changes were recorded during rearing. Antinuclear antibodies (ANA), antiādsDNA, and antiāsnRNP were detected in the mouse serum using an enzymeālinked immunosorbent assay. Apoptosis of Th1 and Th2 immune cells in mice was detected using flow cytometry. Reverse transcription polymerase chain reaction was used to detect the expression of Tābet, GATA3, and Wnt3a mRNA in the spleens of each group. Western blot analysis was performed to detect the expression of Wnt1, pāĪ²ācatenin, Ī²ācatenin, glycogen synthase kinsase3Ī² (GSKā3Ī²), Wnt3a, cāmyc, and cyclin D1 protein in mice spleens. Ī²ācatenin in mice spleen was visualized using immunohistochemistry. Results VitD did not substantial reduce the body weight of MRL/LPR mice, whereas the inhibitor did. VitD notably decreased the concentrations of ANA, antiādoubleāstranded DNA, and antiāsnRNP in the serum of MRL/LPR mice and alleviated apoptosis of Th1 and Th2 cells. VitD markedly increased the expression of Tābet and GATA mRNA in the spleen of MRL/LPR mice and consequently increased the levels of Wnt3a and Ī²ācatenin. Western blot analysis revealed that the levels of GSKā3Ī², pāĪ²ācatenin, Wnt1, Wnt3a, cāmyc, and cyclin D1 could be reduced by VitD, compared with MRL/LPR. Immunohistochemistry demonstrated that the expression of Ī²ācatenin was the most pronounced in the spleen of MRL/LPR mice, and the expression level of Ī²ācatenin decreased substantially after VitD intervention. Conclusions VitD can further inhibit the nuclear translocation of Ī²ācatenin by downregulating the expression of Wnt ligands (Wnt1 and Wnt3a), which reduces the expression of the downstream target gene cyclin D1. Systemic lupus erythematosus in mice was improved by inhibiting the activation of Wnt/Ī²ācatenin signal pathway
Study on the Penetration Performance of a 5.8 mm Ceramic Composite Projectile
The penetration ability of a 5.8 mm standard projectile can be improved by inserting a ZrO2 ceramic ball with high hardness, high temperature, and pressure resistance at its head. Thereby, a ceramic composite projectile can be formed. A depth of penetration (DOP) experiment and numerical simulation were conducted under the same condition to study the armor-piercing effectiveness of a standard projectile and ceramic composite projectile on 10 mm Rolled Homogeneous Armor (RHA) and ceramic/Kevlar composite armor, respectively. The results show that both the ceramic composite and standard projectiles penetrated the armor steel target at the same velocity (850 m/s). The perforated areas of the former (Ļ5 mm & Ļ2 mm) were 2.32 and 2.16 times larger, respectively, than those of the latter. The residual core masses of these two projectiles (Ļ5 mm & Ļ2 mm) were enhanced by 30.45% and 22.23%. Both projectiles penetrated the ceramic/Kevlar composite armor at the same velocity (750 m/s). Compared with the standard projectile, the residual core masses of the ceramic composite one (Ć5 mm & Ć2 mm) were enhanced by 12.4% and 3.6%, respectively. This paper also analyzes the penetration mechanism of the ceramic composite projectile on target plates by calculating its impact pressure. The results show that the ceramic composite projectile outperformed the standard projectile in penetration tests. The research results are instructive in promoting the application of the ZrO2 ceramic composite in an armor-piercing projectile design
Study on the Penetration Performance of a 5.8 mm Ceramic Composite Projectile
The penetration ability of a 5.8 mm standard projectile can be improved by inserting a ZrO2 ceramic ball with high hardness, high temperature, and pressure resistance at its head. Thereby, a ceramic composite projectile can be formed. A depth of penetration (DOP) experiment and numerical simulation were conducted under the same condition to study the armor-piercing effectiveness of a standard projectile and ceramic composite projectile on 10 mm Rolled Homogeneous Armor (RHA) and ceramic/Kevlar composite armor, respectively. The results show that both the ceramic composite and standard projectiles penetrated the armor steel target at the same velocity (850 m/s). The perforated areas of the former (Ļ5 mm & Ļ2 mm) were 2.32 and 2.16 times larger, respectively, than those of the latter. The residual core masses of these two projectiles (Ļ5 mm & Ļ2 mm) were enhanced by 30.45% and 22.23%. Both projectiles penetrated the ceramic/Kevlar composite armor at the same velocity (750 m/s). Compared with the standard projectile, the residual core masses of the ceramic composite one (Ć5 mm & Ć2 mm) were enhanced by 12.4% and 3.6%, respectively. This paper also analyzes the penetration mechanism of the ceramic composite projectile on target plates by calculating its impact pressure. The results show that the ceramic composite projectile outperformed the standard projectile in penetration tests. The research results are instructive in promoting the application of the ZrO2 ceramic composite in an armor-piercing projectile design
The Influence of Closed-Cell W-Shaped Liner Parameters on the Penetration Performance of Integral Annular Shaped Charge
To further enhance the hole-opening ability of the metal jet formed by the annular shaped charge on the armored steel target, a new annular shaped charge structure of a closed-cell W-shaped charge liner is designed based on a certain penetration depth. The impact of the length-diameter ratio of the charge, the inverted cone angle, and the cone angle of the liner on the opening diameter of the annular metal jet are studied through the orthogonal optimization of the annular shaped charge structures carried out by numerical simulation, which shows that the inverted cone angle and the cone angle of the liner are among the main factors that affect penetration depth and the opening diameter of the annular jet, respectively. According to this, an optimum annular charge structure considering both penetration depth and opening diameter is designed and tested by experiments. According to the results, the optimized annular jet records an opening diameter of 0.83 CD (Charge Diameter) when it penetrates the armored steel target with a thickness of 0.53 CD. The experimental results are consistent with the numerical simulation. The research results have certain practical engineering significance for guiding the design of the front-stage annular shaped charge structure of the multi-effect destructive warhead
Study on the Penetration Power of ZrO2 Toughened Al2O3 Ceramic Composite Projectile into Ceramic Composite Armor
This work aims to improve the penetration ability of a 14.5 mm standard armor-piercing projectile into ceramic/armor steel (Al2O3/RHA) composite armor. To this end, ZrO2 toughened Al2O3(ZTA) is prepared as the material for bullet tips, utilizing in situ solidification injection molding that is realized via ceramic dispersant hydrolytic degradation. The penetration power of ZTA ceramic composite projectile, compared with standard armor, against 15 mm armor steel (RHA) and 30 mm Al2O3/RHA composite armor, is studied by ballistics testing combined with numerical simulation. The Tate theory is optimized and then employed to calculate the penetration depth and bullet core’s residual mass when ZTA ceramic composite projectile penetrates into Al2O3/RHA composite armor. The results show that when penetrating RHA of 15 mm, the penetration area of ZTA ceramic composite projectile into RHA increases by 27.59% and the exit area by 42.93%. While the standard projectile fails to penetrate the 30 mm Al2O3/RHA composite armor, the ZTA ceramic composite armor-piercing projectile succeeds, with the mass loss reduced by 66.67% over the standard one. The ZTA ceramic composite bullet has a better performance than the standard bullet in penetrating RHA and Al2O3/RHA composite armors. The test results, simulation, and theoretical analysis are consistent. This study has practical values for engineering applications to design new ceramic composite bullets