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With the development of urban rail transit, taking the metro train has become one of the main modes of transportation, and passengers have an increasing demand for the comfort of taking the metro trains. This paper mainly discusses the impact of noise and vibration caused by metro train on passengers. All 13 metro lines in Guangzhou, China, were selected to conduct the questionnaire survey on the subjective perception of 601 respondents. At the same time, noise and vibration measurements were carried out in the train. The results show that the distribution of noise and vibrations along the metro lines is not uniform, and 50.6% of the interviewees are disturbed by noise. Wheel-rail squeal was found to be the most annoying and disturbing noise source. Three dose-response relationships for noise, vertical vibration, and horizontal vibration are proposed, respectively. The proposed dose-response relationship can be applied to the evaluation of noise annoyance or vibration perception in an environment similar to metro lines. Once the noise or vibration level of a metro line is obtained, the noise disturbance or vibration perception can be estimated. As for the dose-response relationship of vibration perception, people's sensitivity to vibration is much lower than that to noise. Horizontal vibrations are more acceptable to passengers, while vertical vibrations are more disturbing to passengers. The results are helpful to predict the noise annoyance and vibration perception of train passengers between metro stations, and to achieve the purpose of designing effective noise and vibration reduction measures.

A straightforward approach was proposed to modify cotton fabric for oil/water separation based on musselinspired reaction. The poly(DMA-Octadecyl acrylate) was designed to contain key chemical constituents present in mussel adhesive proteins by free radical polymerization of dopamine hydrochloride and octadecyl acrylate, which strongly adsorbed to fabric substrates, providing a special surface for fabric. The chemical structure, surface topography, and surface wettability of the fabric were characterized. The results showed that as-prepared cotton fabric displayed a high CA of >150° when dripped water droplets were on the modified fabric surface, and the oil contact angle (OCA) was close to 0°, it had excellent potential to be used in practical applications and has created a new method of fabric modification for oil/water separation.

The Brassica genus encompasses three diploid and three allopolyploid genomes, but a clear understanding of the evolution of agriculturally important traits via polyploidy is lacking. We assembled an allopolyploid Brassica juncea genome by shotgun and single-molecule reads integrated to genomic and genetic maps. We discovered that the A subgenomes of B. juncea and Brassica napus each had independent origins. Results suggested that A subgenomes of B. juncea were of monophyletic origin and evolved into vegetable-use and oil-use subvarieties. Homoeolog expression dominance occurs between subgenomes of allopolyploid B. juncea, in which differentially expressed genes display more selection potential than neutral genes. Homoeolog expression dominance in B. juncea has facilitated selection of glucosinolate and lipid metabolism genes in subvarieties used as vegetables and for oil production. These homoeolog expression dominance relationships among Brassicaceae genomes have contributed to selection response, predicting the directional effects of selection in a polyploid crop genome.

The PLA/PAE blends with four different weight ratios were prepared by melt mixing. PLA and PAE in PLA/PAE blends were almost immiscible while the weak interaction between PLA and PAE existed. The sub-micrometer PAE domains were dispersed in PLA matrix uniformly. The physical aging of PLA could be inhibited by introducing PAE. For PLA/PAE, the structure formed by physical aging at room temperature induced the accelerated crystallization of PLA during heating. However, for neat PLA, the structure formed by physical aging had a negligible effect on the crystallization of PLA during heating. The isothermal crystallization kinetics of neat PLA and PLA/PAE were analyzed by Avrami theory. The values of Avrami exponent were within the range 2.1–3.0. The crystallization rate of PLA was enhanced significantly by addition of PAE.

Following publication of this article, the authors have corrected 426 chimeric scaffolds in this genome (total scaffold number 10,684). The genome assembly has now been improved as V1.5, and the updated genome assembly is available to be downloaded from http://brassicadb.org/brad/datasets/pub/Genomes/Brassica_juncea/V1.5/ .