Search

Trehalose, trehalose-6-phosphate synthase (TPS),and trehalose-6-phosphatase (TPP) have been reported to play important roles in plant abiotic stress and growth development. However, their functions in the flowering process of Rosa hybrida have not been characterized. In this study we found that, under a short photoperiod or weak light intensity, the content of trehalose in the shoot apical meristem of Rosa hybrida cv 'Carola' significantly decreased, leading to delayed flowering time. A total of nine RhTPSs and seven RhTPPs genes were identified in the genome. Cis-element analysis suggested that RhTPS and RhTPP genes were involved in plant hormones and environmental stress responses. Transcriptome data analysis reveals significant differences in the expression levels of RhTPSs and RhTPPs family genes in different tissues and indicates that RhTPPF and RhTPPJ are potential key genes involved in rose flower bud development under different light environments. The results of quantitative real-time reverse transcription (qRT-PCR) further indicate that under short photoperiod and weak light intensity all RhTPP members were significantly down-regulated. Additionally, RhTPS1a, RhTPS10, and RhTPS11 were up-regulated under a short photoperiod and showed a negative correlation with flowering time and trehalose content decrease. Under weak light intensity, RhTPS11 was up-regulated and negatively regulated flowering, while RhTPS5, RhTPS6, RhTPS7b, RhTPS9, and RhTPS10 were down-regulated and positively regulated flowering. This work lays the foundation for revealing the functions of RhTPS and RhTPP gene families in the regulation of rose trehalose. [ABSTRACT FROM AUTHOR]

Herein, an oxidation‐controlled SnS2 gas sensor is reported. Different oxidation levels of SnS2 are constructed by adjusting the dosage ratio of reagents. The sensing response of oxidized SnS2 to NH3 is studied, and the working mechanism is explored. Results demonstrate that the different oxidation levels of SnS2 exhibit significantly improved gas‐sensing properties. In particular, oxidation‐controlled SnS2 (SnS2‐2 sample) shows a high response to NH3 (92 000%) with a fast response recovery time (17/2 s). The novelty of this work lies in the simple synthesis of SnS2 with oxidation regulation and its application as a high‐sensitivity NH3 gas sensor at room temperature. [ABSTRACT FROM AUTHOR]

The use of recycled aggregate concrete (RAC) in construction is one of the most effective ways to solve the environmental problems of concrete waste. The purpose of the present study is to improve the high-temperature resistance of RAC by incorporating hybrid cellulose and basalt fibers. The mechanical properties of the specimens with different volume fractions of cellulose and basalt fibers after high temperature were studied. Additionally, in order to study the degradation behavior of the specimens, the microstructure of interface between fibers and the cement matrix of RAC was examined by scanning electron microscope. Results show that hybrid fiber can reduce the explosive spalling and mass loss of RAC after being subjected to high temperatures. Compared with the brittle failure of RAC, the failure mode of hybrid fiber recycled aggregate concrete (HFRAC) was transformed into ductile failure under compression and splitting test. After high temperature, the compressive strength and splitting tensile strength of HFRAC were higher than those of RAC, and the cellulose–basalt fibers displayed an excellent synergistic effect on the mechanical properties of RAC. Among all the RAC specimens with different volume fractions of cellulose and basalt fibers, specimen hybrid with 0.15% cellulose fiber and 0.15% basalt fiber showed the best mechanical properties. Microstructure analysis research shows that small channels can be left in the matrix after the melting of cellulose fiber after elevated temperature, which improves the permeability of concrete and reduces the spalling damage of RAC. [ABSTRACT FROM AUTHOR]

In this paper, the heterostructure of MoS2/WS2 was prepared by a hydrothermal method; the n-n heterostructure was demonstrated using TEM combined with Mott-Schottky analysis. The valence and conduction band positions were further identified by the XPS valence band spectra. The NH3-sensing properties were assessed at room temperature by changing the mass ratio of the MoS2 and WS2 components. The 50 wt%-MoS2/WS2 sample exhibited the best performance, with a peak response of 23643% to NH3 at a concentration of 500 ppm, a minimum detection limit of 20 ppm, and a fast recovery time of 2.6 s. Furthermore, the composites-based sensors demonstrated an excellent humidity immune property with less than one order of magnitude in the humidity range of 11–95% RH, revealing the practical application value of these sensors. These results suggest that the MoS2/WS2 heterojunction is an intriguing candidate for fabricating NH3 sensors. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to propose a method for better discovering topic evolution path and semantic relationship from the perspective of patent entity extraction and semantic representation. On the one hand, this paper identifies entities that have the same semantics but different expressions for accurate topic evolution path discovery. On the other hand, this paper reveals semantic relationships of topic evolution for better understanding what leads to topic evolution. Design/methodology/approach: Firstly, a Bi-LSTM-CRF (bidirectional long short-term memory with conditional random field) model is designed for patent entity extraction and a representation learning method is constructed for patent entity representation. Secondly, a method based on knowledge outflow and inflow is proposed for discovering topic evolution path, by identifying and computing semantic common entities among topics. Finally, multiple semantic relationships among patent entities are pre-designed according to a specific domain, and then the semantic relationship among topics is identified through the proportion of different types of semantic relationships belonging to each topic. Findings: In the field of UAV (unmanned aerial vehicle), this method identifies semantic common entities which have the same semantics but different expressions. In addition, this method better discovers topic evolution paths by comparison with a traditional method. Finally, this method identifies different semantic relationships among topics, which gives a detailed description for understanding and interpretation of topic evolution. These results prove that the proposed method is effective and useful. Simultaneously, this method is a preliminary study and still needs to be further investigated on other datasets using multiple emerging deep learning methods. Originality/value: This work provides a new perspective for topic evolution analysis by considering semantic representation of patent entities. The authors design a method for discovering topic evolution paths by considering knowledge flow computed by semantic common entities, which can be easily extended to other patent mining-related tasks. This work is the first attempt to reveal semantic relationships among topics for a precise and detailed description of topic evolution. [ABSTRACT FROM AUTHOR]