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This study investigated the role of constructing a dual network in toughening bio-based long-chain polyamide 610 (PA610) composites. Rheological studies were conducted to reveal the effects of toughening agent type and content on the material properties. According to the variation trend of mechanical properties and the appearance of a rheological low-frequency plateau of the materials, the percolation network concentration ϕc of the toughening agent in the PA610 matrix was determined to be 13.5 vol.%. The interfacial interaction of the composite was evaluated through the percolation theory, and the scaling value v = 1.36 for both indicated the good affinity between PA610 and the toughening agent. Rheology results found that the combination of ethylene terpolymer (PTW) and maleic anhydride-g-styrene-b-(ethylene-butylene)-b-styrene (MAH-SEBS) could achieve an optimal balance between the mechanical properties and fluidity of the composites. Furthermore, the addition of ultra-high-molecular-weight polytetrafluoroethylene (PTFE), in conjunction with the toughening agent, facilitated the construction of a dual semi-interpenetrating network. The strengthened intermolecular interactions restricted the relative slippage and mobility of the polymer chains and therefore enhanced the strength and toughness of the material. This study provides new possibilities and approaches for optimizing the comprehensive properties of bio-based polyamide materials. [ABSTRACT FROM AUTHOR]

Ride-hailing services provide an efficient way to travel, but they also cause some safety incidents, which make female passengers uneasy. Analyzing the safety perceptions of female passengers, particularly their psychological and emotional responses, can assist operators in developing effective solutions and safe travel environments for them. This study explores factors that are likely to affect the safety perception of female ride-hailing passengers using a subjective method (data was obtained from 596 Chinese female passengers). The methodologies adopted mainly include confirmatory factor analysis (CFA) and a maximum-likelihood structural equation model (ML-SEM). A passenger safety perception model is developed by considering various elements such as safety expectation, platform trust, perceived environment, and safety awareness. The results revealed that safety perception is positively influenced by perceived environment and safety expectation (containing three subdimensions, namely, driver behavior, traveling together, and mobile phone dependence). The effects of safety awareness and platform trust on safety perception are mediated by perceived environment and safety expectation, respectively. Regarding overall effects, safety expectation is the most powerful predictor for safety perception of female ride-hailing passengers, followed by platform trust, perceived environment, and safety awareness. Finally, countermeasures are offered from the perspectives of operators, drivers, and passengers to enhance the safety perception of female ride-hailing passengers. A high level of ride-hailing safety would undoubtedly boost the female passenger's trust and consequently ridership., Author(s): Yazao Yang (corresponding author) [1]; Shixingyue Hu [1]; Dingling Liao [1]; Xianbo Huang [1] 1. Introduction Ride-hailing originated from combining information and communications technology (ICT) and digitized taxi operation, [...]

This article discusses the development of marker-free transgenic rice that exhibits stable and enhanced resistance to Rice ragged stunt virus (RRSV) and Rice grassy stunt virus (RGSV) through RNA interference (RNAi) technology. Rice virus diseases pose a serious threat to rice production, and the development of resistant varieties is crucial. The researchers used a double T-DNA vector transformation method combined with RNAi technology to construct a dual-action RNAi vector without selectable markers. The marker-free transgenic rice showed strong and stable resistance to the viruses without affecting yield, offering higher biosafety. These findings provide valuable material support for future research on rice virus resistance and germplasm innovation. [Extracted from the article]

A significantly growing interest is to design new biodegradable polymers in order to solve fossil resources and environmental pollution problems associated with conventional plastics. A kind of new biodegradable polymers, aliphatic–aromatic co-polyesters have been researched widely and developed rapidly in recent years, since that can combine excellent biodegradability provided from aliphatic polyesters and good properties from aromatic polyesters. Out of which, poly (butylene-adipate-co-terephthalate) (PBAT) shows the most importance. PBAT has been commercialized by polycondensation reaction of butanediol (BDO), adipic acid (AA) and terephthalic acid (PTA) using general polyester manufacturing technology. And it has been considered to have desirable properties and competitive costs to be applied in many fields. Therefore, this review aims to present an overview on the synthesis, properties and applications of PBAT. Keywords: Biodegradation, Polyester, PBAT, Synthesis, Property, Application

Male sterility in plants provides valuable breeding tools in germplasm innovation and hybrid crop production. However, genetic resources for dominant genic male sterility, which hold great promise to facilitate breeding processes, are extremely rare in natural germplasm. Here we characterized the Sanming Dominant Genic Male Sterility in rice and identified the gene SDGMS using a map-based cloning approach. We found that spontaneous movement of a 1978-bp long terminal repeat (LTR) retrotransposon into the promoter region of the SDGMS gene activates its expression in anther tapetum, which causes abnormal programmed cell death of tapetal cells resulting in dominant male sterility. SDGMS encodes a ribosome inactivating protein showing N-glycosidase activity. The activation of SDGMS triggers transcription reprogramming of genes responsive to biotic stress leading to a hypersensitive response which causes sterility. The results demonstrate that an ectopic gene activation by transposon movement can give birth to a novel trait which enriches phenotypic diversity with practical utility. [ABSTRACT FROM AUTHOR]

The self-assembly behaviors of ABn miktoarm star copolymers as one typical type of asymmetric architecture have been studied well in the past few decades due to their deflected phase boundaries. In particular, recently, they have attracted renewed theoretical interest due to their expanded spherical phase region that stabilizes complex Frank–Kasper spherical phases. However, previous theoretical studies have never considered ABn copolymers with unequal arm lengths, which is more or less the case for synthesized copolymers. In this work, we investigate the self-assembly behaviors of ABn miktoarm star copolymers with unequal B-arms using self-consistent field theory. We propose an intramolecular polydispersity index (iĐ) to quantify the distribution of unequal B-blocks. Accordingly, we further propose a simple quantity of an effective arm number nequ = n/iĐ for quantitatively comparing the phase boundaries between various ABn copolymer samples with different arm numbers or different distributions of B-blocks. Our results indicate that different ABn copolymers with equal nequ exhibit similar phase diagrams. On the other hand, we also found that the phase boundaries of two different samples with same nequ are not exactly overlapped. We speculate that the effect of spontaneous curvature may be mainly controlled by nequ, but the packing frustration of B-blocks may also be dependent on the other quantities that are closely related to the shape of the distribution of B-arms, such as higher order polydispersity indexes. [ABSTRACT FROM AUTHOR]