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AbstractThe complete mitochondrial genome sequence of Goniurosaurus varius is 17778 bp in length (GenBank accession number OQ992199), containing 13 protein-coding genes, 2 rRNA genes, and 22 tRNA genes. The gene order and orientation are identical to those of other Eublepharidae species in the GenBank database. Seven protein-coding genes (COX2, COX3, ND1, ND2, ND3, ND4 and CYTB) exhibit incomplete stop codon ‘T.’ Phylogenetic analysis revealed the monophyly of Goniurosaurus and Eublepharidae and suggested that G. varius is closely related to the lineage composed of G. luii and G. liboensis. Distinct from other published Eublepharidae species, G. varius contains an extra non-coding region between tRNA-Thr and tRNA-Pro, which may be formed by gene rearrangements. The complete mitochondrial genome will be helpful for further studies on the population genetics of this species and phylogenetic analyses of Eublepharidae.

Flattening large-diameter cylindrical heat pipes to fabricate thin heat pipes can significantly improve their heat transfer performance in theory, but their appropriate wick structures and thermal performance are still unclear. In this work, a novel composite wick structure sintered from spiral woven mesh and orthogonal woven mesh was developed for large-diameter thin flattened heat pipes. Their diameter and thickness were 8 and 1.0 mm, respectively. Seven types of wick structures for the experimental heat pipes were designed to investigate the effects of the length and position of the orthogonal woven mesh on the thermal performance. The results indicated that based on the spiral woven mesh, sintering the orthogonal woven mesh in the evaporator and adiabatic sections of the heat pipe can significantly improve the thermal performance. Compared with the single spiral woven mesh wick, the maximum heat transport capacity of the experimental heat pipe with optimal composite wick increased by 41.67%, and the evaporation and total thermal resistances decreased by 68.41% and 61.49%, respectively. This study provided very useful guidance for improving the thermal performance of the large-diameter thin flattened heat pipes for cooling laptops.

Abstract Aim Our study aimed at investigating the risk perception of nurses and related factors in the era of COVID‐19 period. Design Cross‐sectional study. Methods Four hundred and forty‐two participants completed an online questionnaire relating to their risk perception on public health emergencies. Data were collected between 25 November 2020 and 1 December 2020. Kruskal–Wallis test, Mann–Whitney U test and Ordinal logistic regression analysis were used to examine factors impacting on risk perception. Results 65.2% of nurses' risk perception of COVID‐19 was the moderate level even below the moderate level in the postperiod of COVID‐19. Kruskal–Wallis test results indicated significant differences in gender, age, education status, working years, professional title, postlevel, COVID‐19 contact experience, marital status and health status (p

Based on the magnetorheological chemical composite polishing principle of Fenton reaction, the magnetorheological chemical composite polishing experiment was carried out on single crystal SiC substrate, and the influence of process parameters on the polishing effect was studied. The results show that with the increase of diamond particle size, material removal increases first and then decreases, while surface roughness decreases first and then increases. With the increase of abrasive mass fraction, material removal rate increases, and surface roughness decreases first and then increases. When the mass fraction of carbonyl iron powder increases, material removal rate increases, while surface roughness decreases first and then increases. With the increase of oxidant mass fraction, material removal increases first and then decreases, while the surface roughness decreases first and then increases. The influence of machining gap on material removal rate varies greatly. When machining gap is 1.0 mm, machined surface quality is better. With the increase of workpiece speed and polishing disc speed, the material removal rate first increases and then decreases, and the surface roughness first decreases and then increases. The optimized process parameters are as follows: the abrasive particle size is 1.0 μm, the mass fraction is 5%, the mass fraction of carbonyl iron powder is 25%, the mass fraction of hydrogen peroxide is 5%, the machining gap is 1.0 mm, the workpiece speed is 500 r/min, and the polishing disc speed is 20 r/min. The single crystal SiC with surface roughness of about 40.00 nm was processed with optimized process parameters to obtain a smooth surface with surface roughness of less than 0.10 nm.