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Surface adjustment is an important process in the phosphating process before painting， and its effect directly affects the phosphating crystal morphology. In order to clarify the adsorption property of surface conditioning agent for phosphating on the surface of high strength steel，the exsisting state of elements on the surface of high strength steel was analyzed by X-ray photoelectron spectroscopy (XPS)，scanning electron microscope (SEM)， focused ion beam (FIB) and transmission electron microscope (TEM)， and the adsorption properties of oxides on the surface of high strength steel to the surface conditioning agent particles were analyzed by absorption kynetic experiment. Furthermore， a brief phosphating treatment was performed on the surface of the high strength steel after surface adjustment to examine the initial nucleation state of phosphate. Results showed that the oxides with the highest contents on the surface of high strength steel were Fe2O3 and MnO. Compared with Fe2O3， MnO had a stronger adsorption capacity for surface conditioning agent particles， and could adsorb surface conditioning agent particles preferentially in competitive adsorption. Combining the above-mentioned results with the morphology and element distribution of the surface and cross section of the high-strength steel， it could be proved that the MnO on the surface of the high strength steel was the key to the adsorption of surface conditioning agent particles， and the initial deposition of phosphate occurred at the sites with the surface conditioning agent particles.

Lateral compressions of (n, n) and (n, 0) single-walled carbon nanotube (SWCNT) bundles are simulated by density functional theory. Feasible transition pathways are verified by the body-centered tetragonal C4 (bct-C4) phase from the (4, 4) bundle and the carbon-centered orthorhombic C8 (Cco-C8) phase from (6, 6) and (8, 8) bundles. Three new phases, the sp3-hybridized phases Cco-C16 from the (4, 0) bundle and Cco-C32 from the (8, 0) bundle, the hexagonal phase Hex-C24 composed of sp2- and sp3-hybridized carbons from the (6, 0) bundle, under non-proportional triaxial loading are predicted. Measured hardness values for Cco-C16/C32 exceed 40 GPa, indicating super-hardness. Electronic band structures of Cco-C16/C32 exhibit a 3.64 eV bandgap, while Hex-C24 exhibits metallic carbon properties. Our results provide the potential phase transition pathways of SWCNT bundles under non-proportional compression. [ABSTRACT FROM AUTHOR]

Atherosclerosis, a lipid‐driven chronic inflammatory disorder, is a significant global health concern associated with high rates of morbidity and mortality, imposing a substantial societal burden. The purpose of this study is to investigate the possible molecular mechanisms of atherosclerosis and identify potential therapeutic targets. We conducted an integrated bioinformatics analysis using data from peripheral blood mononuclear cell and TISSUE databases obtained from the Gene Expression Omnibus, to identify key genes associated with the progression of atherosclerosis. Here, IRF8 was found to be a key gene in atherosclerosis patients. Silencing IRF8 with small interfering RNA reduced inflammation in endothelial cells. This suggests IRF8 is a crucial biomarker for immune infiltration in atherosclerosis advance. [ABSTRACT FROM AUTHOR]

The analysis and evaluation of missile operational effectiveness is an effective means for comprehensive evaluation of missile weapon system performance. Single air-to-air missile is easy to be interfered by the environment and limited by the target in the process of air combat. The cooperative operation of multiple air-to-air missiles can enrich the operation style and improve the strike efficiency. On the basis of the existing single missile effectiveness evaluation methods, an efficiency evaluation method based on missile parameters, considering the miss distance of multiple missiles and missile formation structure is proposed. The simulation and evaluation analysis are carried out with the AIM-120D to verify the effectiveness of the method.

Graphene nanoribbon woven fabrics (GNWFs) with excellent mechanical properties are promising for ballistic armor materials. The dynamic response of single-layer and bilayer GNWFs under nano-projectile impact at high-speed (4–5 km s−1) is investigated by molecular dynamics simulations. Results show that the woven structure is determined by the bandwidth and gap spacing, which influences the deformation/fracture and motion coupling effects of the crossed nanoribbons and the ballistic performance of GNWF. Owing to the perturbation of the van der Waals (vdW) interface between nanoribbons, the specific penetration energy of GNWFs reaches 16.02 MJ kg−1, which is much higher than that of single-layer graphene (10.80 MJ kg−1) and bilayer graphene (10.07 MJ kg−1). The peculiarities of woven structure minimize the damage of GNWFs, on the one hand, the reversibility of vdW interactions and the entanglement of nanoribbons provide GNWFs a certain self-healing ability. On the other hand, the porous nanostructure of twist-stacked bilayer GNWFs tends to be uniform and dense with the twist angle, which improves the impact resistance. This study provides more understanding of the ballistic properties of GNWFs and the design of nano-fabrics based on two-dimensional materials. [ABSTRACT FROM AUTHOR]

The atomistic behavior and mechanical properties of twisted graphene/h-BN (T-GBN) heterostructures under hydrostatic high-pressure is investigated using density functional theory with the Perdew–Burke–Ernzerhof functional. Systematic explorations of T-GBN heterostructures with different twist angles (9.43°, 13.17°, and 21.78° characterized by moiré patterns) reveal that stable phases, denoted as Moiré-BC2N (m-BC2N), are formed. Notably, the m-BC2N (21.78°) phase maintains perfect sp3 hybridization, even upon complete relaxation to zero pressure, and its mechanical stability is confirmed; comprehensive mechanical evaluations unveil the crystal anisotropic attributes, further highlighting its exceptionally high hardness. Specifically, m-BC2N (21.78°) demonstrates an impressive hardness of 74.7 GPa. Furthermore, electronic structure analysis of m-BC2N exhibits wide bandgaps (Eg), , comparable to diamond, while m-BC2N (9.43°) exhibits a lower bandgap,. This study sheds light on designing novel BCN ternary structures with outstanding mechanical properties under high pressures. [ABSTRACT FROM AUTHOR]

Background. Negative-pressure wound therapy is applied increasingly to manage closed wounds. However, no consensus has been reached with regard to surgical site infection and wound complication. Aim. To evaluate the effect of negative pressure therapy on closed wounds after orthopedic surgeries. Methods. PubMed, EMBASE, Cochrane Library, and MEDLINE databases were searched from 1966 to January 2019; the references in the identified studies were also searched. Results. Ten studies on arthroplasty and 3 studies on fractures were included. Significantly few infections appeared in the negative pressure group (odds ratio [OR] = 0.28, 95% confidence interval [CI] = 0.18-0.46, P < .001; I2 = 0%, P = .80). There was no significant difference for other complications (OR = 0.54, 95% CI = 0.21-1.39, P = .20; I2 = 81%, P < .001). Few patients needed reoperation in the negative pressure group (OR = 0.28, 95% CI = 0.14-0.53, P < .001; I2 = 0%, P = .82). Conclusion. Negative pressure therapy can decrease surgical site infection and reoperation of closed incisions. [ABSTRACT FROM AUTHOR]

In this paper, jute/PLA composites were prepared by using twin‐screw extrusion, and injection molding with weight percent of jute fibers was 10%. A saline solution (pH = 7.48 ± 0.1) was prepared adding 0.05 g/mL of sodium chloride. A solution of NaOH with pH = 8.53 ± 0.1 was also prepared. Its water absorption, pH value, and mechanical properties were measured and differential scanning calorimetry, gel permeation chromatography, scanning electron microscopy were performed to analyze the aging mechanism of jute/PLA composite in saline and alkaline solution at 23°C. The results showed that the weight gain for jute/PLA composite immersed in alkaline solution was higher than that immersed in saline solution. The pH of alkaline solution declined faster than saline solution due to the neutralization of alkali and lactic acid, which produced from the hydrolysis of PLA. All the aged composites have a decline on mechanical properties in both solutions due to the degradation of jute fiber, PLA, and the interface between fiber and matrix. Mechanical strength of the composites under alkaline environment was lower than that of the composites under saline environment after aging. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most malignant and aggressive glioma, which has a very poor prognosis. Temozolomide (TMZ) is still a first‐line treatment, but resistance is inevitable even in MGMT‐deficient glioblastoma cells. The aims of this study were to comprehend the effect of TMZ on nucleus and the underlying mechanism of acquired TMZ resistance in MGMT‐deficient GBM. We show the changes of nuclear proteome in the MGMT‐deficient GBM U87 cells treated with TMZ for 1 week. Label‐free–based quantitative proteomics were used to investigate nuclear protein abundance change. Subsequently, gene ontology function annotation, KEGG pathway analysis, protein‐protein interaction (PPI) network construction analysis of DAPs, and immunofluorescence were applied to validate the quality of proteomics. In total, 457 (455 gene products) significant DAPs were identified, of which 327 were up‐regulated and 128 were down‐regulated. Bioinformatics analysis uncovered RAD50, MRE11, UBR5, MSH2, MSH6, DDB1, DDB2, RPA1, RBX1, CUL4A, and CUL4B mainly enriched in DNA damage repair related pathway and constituted a protein‐protein interaction network. Ribosomal proteins were down‐regulated. Cells were in a stress‐responsive state, while the entire metabolic level was lowered. Significance of the study: In U87 cell treated with TMZ for 1 week, which resulted in DNA damage, we found various proteins dysregulated in the nucleus. Some proteins related to the DNA damage repair pathway were up‐regulated, and there was a strong interaction. We believe this is the potential clues of chemotherapy resistance in tumour cells. These proteins can be used as indicators of tumour resistance screening in the future. [ABSTRACT FROM AUTHOR]