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Granite residual soil is widely distributed in Southeastern China. Such soils exhibit mechanical characteristics such as loose, rich cracks and easy disintegration, resulting in severe soil erosion disasters under rainfall conditions. Microbial-induced carbonate precipitation (MICP) is a green alternative for soil stabilization. In this study, a new strategy for the disintegration control of granite residual soil using MICP technology is proposed. The effects of the bacterial solution concentration, the cementation solution concentration, and the treatment cycle are investigated through a disintegration test. The optimal treatment parameters for granite residual soil using MICP technology are determined by analyzing the disintegration processes and residual quality indicators of disintegration. The results show that the treated samples have three types of disintegration: complete disintegration, incomplete disintegration, and non-disintegration. The precipitated calcium carbonate (CaCO3) bonds the soil particles and fills the pores. Taking into account the effectiveness and cost and a bacterial solution concentration OD600 = 0.75, five cycles of MICP treatment with a cementation solution concentration of 1.2 mol/L is optimal for the disintegration control of granite residual soil. The cementation-action effects of CaCO3 are verified through scanning electron microscopy (SEM) tests with an energy-dispersive X-ray (EDX) spectroscope. These findings suggest that MICP is a promising candidate to control the disintegration of granite residual soil.

Malus sieversii (Ledeb.) M.Roem. is the ancestor of cultivated apples, and is an excellent germplasm resource with high resistance to cold. Artificial refrigerators were used to simulate the low temperature of −3 °C to treat Malus sieversii (Ledeb.) M.Roem. histoculture seedlings. Observations were performed to find the effects of freezing stress on the status of open or closed stomata, photosystems, and detection of metabolomic products in leaves of Malus sieversii (Ledeb.) M.Roem. histoculture seedlings. The percentage of closed stomata in the Malus sieversii (Ledeb.) M.Roem. histoculture seedlings increased, the maximum fluorescence (Fm’) excited by a strong light (saturating pulse) was weakened relative to the real-time fluorescence in its vicinity, and the quantum yield of unregulated energy dissipation was increased in PSII under freezing stress. The metabolites in the leaves of the Malus sieversii (Ledeb. M.Roem.) histoculture seedlings were analyzed by ultra-performance liquid chromatography–tandem mass spectrometry using CK, T12h, T36 h, and HF24h. Results demonstrated that cold stress in the Malus sieversii (Ledeb.) M.Roem. histoculture seedlings led to wilting, leaf stomatal closure, and photosystem damage. There were 1020 metabolites identified as lipids (10.2%), nucleotides and their derivatives (5.2%), phenolic acids (19.12%), flavonoids (24.51%), amino acids and their derivatives (7.75%), alkaloids (5.39%), terpenoids (8.24%), lignans (3.04%), organic acids (5.88%), and tannins (0.88%). There were 110 differential metabolites at CKvsT12h, 113 differential metabolites at CKvsT36h, 87 differential metabolites at T12hvsT36h, 128 differential metabolites at CKvsHF24h, 121 differential metabolites at T12hvsHF24h, and 152 differential metabolites at T36hvsHF24h. The differential metabolites in the leaves of the Malus sieversii (Ledeb.) M.Roem. seedlings grown under low-temperature stress mainly involved glycolysis, amino acid metabolism, lipid metabolism, pyrimidine metabolism, purine metabolism, and secondary metabolite metabolism. The Malus sieversii (Ledeb.) M.Roem. seedlings responded to the freezing stress by coordinating with each other through these metabolic pathways. The metabolic network of the leaves of the Malus sieversii (Ledeb.) M.Roem. histoculture seedlings under low temperature stress was also proposed based on the above pathways to deepen understanding of the response of metabolites of Malus sieversii (Ledeb.) M.Roem. to low-temperature stress and to lay a theoretical foundation for the development and utilization of Malus sieversii (Ledeb.) M.Roem. cultivation resources.

Soybeans are essential crops that supply protein and oil. The composition and contents of soybean fatty acids are relevant to human health and have a significant relationship with soybean oil processing and applications. Identifying quantitative trait locus (QTL) genes related to palmitic acid could facilitate the development of a range of nutritive soybean cultivars using molecular marker-assisted selection. In this study, we used a cultivar with higher palmitic acid content, ‘Dongnong42’, and a lower palmitic acid content cultivar, ‘Hobbit’, to establish F2:6 recombinant inbred lines. A high-density genetic map containing 9980 SLAF markers was constructed and distributed across 20 soybean chromosomes. The genetic map contained a total genetic distance of 2602.58 cM and an average genetic distance of 0.39 cM between adjacent markers. Two QTLs related to palmitic acid content were mapped using inclusive composite interval mapping, explaining 4.2–10.1% of the phenotypic variance in three different years and environments, including the QTL included in seed palmitic 7-3, which was validated by developing SSR markers. Based on the SNP/Indel and significant differential expression analyses of Dongnong42 and Hobbit, two genes, Glyma.15g119700 and Glyma.15g119800, were selected as candidate genes. The high-density genetic map, QTLs, and molecular markers will be helpful for the map-based cloning of palmitic acid content genes. These could be used to accelerate breeding for high nutritive value cultivars via molecular marker-assisted breeding.

Change detection (CD) is in demand in satellite imagery processing. Inspired by the recent success of the combined transformer-CNN (convolutional neural network) model, TransCNN, originally designed for image recognition, in this paper, we present STDecoder-CD for change detection applications, which is a combination of the Siamese network (“S”), the TransCNN backbone (“T”), and three types of decoders (“Decoder”). The Type I model uses a UNet-like decoder, and the Type II decoder is defined by a combination of three modules: the difference detector, FPN (feature pyramid network), and FCN (fully convolutional network). The Type III model updates the change feature map by introducing a transformer decoder. The effectiveness and advantages of the proposed methods over the state-of-the-art alternatives were demonstrated on several CD datasets, and experimental results indicate that: (1) STDecoder-CD has excellent generalization ability and has strong robustness to pseudo-changes and noise. (2) An end-to-end CD network architecture cannot be completely free from the influence of the decoding strategy. In our case, the Type I decoder often obtained finer details than Types II and III due to its multi-scale design. (3) Using the ablation or replacing strategy to modify the three proposed decoder architectures had a limited impact on the CD performance of STDecoder-CD. To the best of our knowledge, we are the first to investigate the effect of different decoding strategies on CD tasks.

The effective conversion of carbon dioxide (CO2) into cyclic carbonates requires porous materials with high ionic content and large specific surface area. Herein, we developed a new systematic post-synthetic modification strategy for synthesizing imidazolium-based hypercrosslinked ionic polymers (HIPs) with high ionic content (up to 2.1 mmol g−1) and large specific surface area (385 m2 g−1) from porous hypercrosslinked polymers (HCPs) through addition reaction and quaternization. The obtained HIPs were efficient in CO2 capture and conversion. Under the synergistic effect of high ionic content, large specific surface area, and plentiful micro/mesoporosity, the metal-free catalyst [HCP-CH2-Im][Cl]-1 exhibited quantitative selectivities, high catalytic yields, and good substrate compatibility for the conversion of CO2 into cyclic carbonates at atmospheric pressure (0.1 MPa) in a shorter reaction time in the absence of cocatalysts, solvents, and additives. High catalytic yields (styrene oxide, 120 °C, 8 h, 94% yield; 100 °C, 20 h, 93% yield) can be achieved by appropriately extending the reaction times at low temperature, and the reaction times are shorter than other porous materials under the same conditions. This work provides a new strategy for synthesizing an efficient metal-free heterogeneous catalyst with high ionic content and a large specific surface area from HCPs for the conversion of CO2 into cyclic carbonates. It also demonstrates that the ionic content and specific surface area must be coordinated to obtain high catalytic activity for CO2 cycloaddition reaction.

Hyper-crosslinking polymers and its immobilized acid ionic liquid catalyst were prepared using cheap pitch, as a monomer, through hyper-crosslinking reactions and allyl chloride, as a chlorine source, for chloromethylation and further grafting with imidazole and functionalizing with sulfonic acid. The polymers were characterized by FE-SEM, FTIR, TG, and nitrogen sorption. The grafting ratios of the chloromethylated pitch-based hyper-crosslinked polymer (HCPpitch−CH2−Cl) and immobilized acid ionic liquid [HCPpitch−Im−Pros][Tos] were 3.5 mmol/g and 3.0 mmol/g, and the BET specific surface areas were 520 m2/g and 380 m2/g, respectively. This strategy provides an easy approach to preparing highly stable and acid functionalized mesoporous catalysts. The immobilized acidic ionic liquid was used as a catalyst for the esterification of oleic acid and methanol to synthesize biodiesel. The results demonstrated that under the optimal conditions of an alcohol to acid molar ratio of 7:1, ionic liquid to oleic acid molar ratio of 0.12, and a reaction time of 3 h at atmospheric pressure, the yield of methyl oleate can reach up to 93%. Moreover, the catalyst was reused five times without the yield decreasing significantly. This study shows that [HCPpitch−Im−Pros][Tos] is a robust catalyst for the synthesis of biodiesel.

The rapid development of new generation sequencing technology has deepened the understanding of genomes and functional products. RNA-sequencing studies in mammals show that approximately 85% of the DNA sequences have RNA products, for which the length greater than 200 nucleotides (nt) is called long non-coding RNAs (lncRNA). LncRNAs now have been shown to play important epigenetic regulatory roles in key molecular processes, such as gene expression, genetic imprinting, histone modification, chromatin dynamics, and other activities by forming specific structures and interacting with all kinds of molecules. This paper mainly discusses the correlation between the structure and function of lncRNAs with the recent progress in epigenetic regulation, which is important to the understanding of the mechanism of lncRNAs in physiological and pathological processes.