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Background The skin is the largest organ of the body and has multiple functions. Wounds remain a significant healthcare problem due to the large number of traumatic and pathophysiological conditions patients suffer. Methods Gene expression profiles of 37 biopsies collected from patients undergoing split-thickness skin grafts at five different time points were downloaded from two datasets (GSE28914 and GSE50425) in the Gene Expression Omnibus (GEO) database. Principal component analysis (PCA) was applied to classify samples into different phases. Subsequently, differentially expressed genes (DEGs) analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway functional enrichment analyses were performed, and protein–protein interaction (PPI) networks created for each phase. Furthermore, based on the results of the PPI, hub genes in each phase were identified by molecular complex detection combined with the ClueGO algorithm. Results Using principal component analysis, the collected samples were divided into four phases, namely intact phase, acute wound phase, inflammatory and proliferation phase, and remodeling phase. Intact samples were used as control group. In the acute wound phase, a total of 1 upregulated and 100 downregulated DEGs were identified. Tyrosinase (TYR), tyrosinase Related Protein 1 (TYRP1) and dopachrome tautomerase (DCT) were considered as hub genes and enriched in tyrosine metabolism which dominate the process of melanogenesis. In the inflammatory and proliferation phase, a total of 85 upregulated and 164 downregulated DEGs were identified. CHEK1, CCNB1 and CDK1 were considered as hub genes and enriched in cell cycle and P53 signaling pathway. In the remodeling phase, a total of 121 upregulated and 49 downregulated DEGs were identified. COL4A1, COL4A2, and COL6A1 were considered as hub genes and enriched in protein digestion and absorption, and ECM-receptor interaction. Conclusion This comprehensive bioinformatic re-analysis of GEO data provides new insights into the molecular pathogenesis of wound healing and the potential identification of therapeutic targets for the treatment of wounds.

The realization method of the explosion-proof three-level frequency conversion equipment for coal mine is introduced in this paper. The frequency conversion equipment uses diode clamped three-level inverter unit topology structure, it overcomes some disadvantages of two-level converter that harmonic content of voltage output is higher, electromagnetic interference is serious and on-off loss is higher. The frequency conversion equipment is suitable for coal mine high voltage and large power devices such as draught fan, pumps and belt conveyers.

Polyfunctional aziridine/polyester microcapsules as control-release waterborne cross-linker were synthesized by multiple emulsion-solvent evaporation method. The results show that, a lower surface free energy with shell polyester is more favourable for the formation of microcapsules. Full encapsulating microcapsules are synthesized with the polyester with a surface free energy of 34.5 mJ/m2. Shell-to-core feeding mass ratio has a significant influence on the morphology and core content of the resulting microcapsules. Well defined spherical microcapsules with uniform shell thickness and core content at around 22% are produced at a shell-to-core mass ratio of 1:1. When 2.5% of colloid stabilizer is used, hollow spherical microcapsules are obtained. A high solvent evaporation rate results in wrinkling and porosity of the microcapsules, and an evaporation rate equivalent to solvent elimination in about 2 h provides a uniform rate of surface hardening. The characterization of the microcapsules by SEM and FTIR demonstrates that polyfunctional aziridine is encapsulated at the centre of the microcapsule. The microcapsules synthesized can be broken at a high shear rate.

An initial model of the HBV epsilon RNA was built by the Biopolymer module of Insight II. While its three-dimensional structure was obtained through structure optimization based on molecular dynamics simulation, the two active sites were found. A comparison with the experimental result indicated that the active sites may be the binding sites of the epsilon RNA in the RT–epsilon interaction. The result will be helpful to further discussion about the mechanism of RT–epsilon interaction and the study of HBV genome replication.

The Magnetic and electric field effects of photoluminescence of excitons bound to nitrogen atom pairs in GaAs have been investigated for nitrogen δ-doped samples grown on (001) GaAs substrates. The excitons bound to nitrogen atom pairs produce a number of photoluminescence lines. However, these lines are much fewer than those observed in uniformly nitrogen-doped samples because of the limited spacing between two-dimensionally distributed nitrogen atoms. Among these lines, those appearing at 1.488, 1.476, and 1.428 eV are the most dominant. In this study, the characteristics of these dominant lines are investigated by an applying external field. The observed phenomena are explained by assuming that there is a continuous flow of excitons from a lower to a higher binding energy state under continuous excitation. Each photoluminescence line is found to split into two or more lines without applying an external field. The lines show a further split under a magnetic field and are finally quenched when the magnetic field is increased. The photoluminescence intensity of each line is modulated by the localization of excitons by a magnetic field and by the delocalization by an electric field.