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Capa peptides are of great importance for both understanding the control of salt balance by neuropeptides and revealing the mechanisms of response to cold stress. Presently, research on the physiological function of neuropeptides typically includes identifying and analysing specific receptors and their interactions. Given their role in osmotic balance and the importance of cold tolerance, this study attempted to identify the sequence and function of Capa peptide receptors (CapaRs) in Dendroctonus armandi and to prove that CapaRs play an important role in the cold stress responses. In this study, two full‐length cDNAs encoding more than 400 amino acids of Dendroctonus armandi Capa peptide receptor genes (DaCapaRs) and their sequence features were identified using bioinformatic analysis methods. The alignment of DaCapaRs with homologous proteins from other species indicated that the most similar are Dendroctonus ponderosae Capa peptide receptors. The expression of DaCapaRs was high in December and in the larvae, adults and head and midgut of Dendroctonus armandi. In addition, with decreasing temperatures and long‐term exposure to cold conditions, the expression of DaCapaRs increased markedly when the temperature was 4 to –10°C. RNA interference analysis demonstrated that DaCapaRs play an important role in the cold tolerance of overwintering larvae and indicated that a reverse interaction occurs between DaCapaRs and aquaporins. The results showed that DaCapaRs play an essential role in understanding the neuropeptide regulation of cold tolerance in overwintering Dendroctonus armandi larvae and that it can assist in understanding adaptive evolution of Dendroctonus armandi and its relationship with the ecological environment of the Qinling Mountains. [ABSTRACT FROM AUTHOR]

Corn stover (CS) is a promising feedstock for producing biomethane, that can replace diminishing fossil fuels. However, the recalcitrant structure of CS resulted in low degradability in anaerobic digestion (AD). Numerous studies investigated the pretreatment of CS before AD, but the insight mechanism of biomethanation enhancement is not fully revealed. Therefore, this study advanced low-temperature urea-hydrothermal pretreatment of CS, and the biomethane production, substance bioconversion, hydrolase activity, and metagenomic analysis were conducted to unravel the intrinsic mechanisms of pretreatment for the enhanced biomethanation. The results showed that the pretreatment improved 11.5% of the specific surface area of CS, providing 111.5% higher total volatile fatty acids and 19.9% higher reducing sugars than the control, potentially enriching more anaerobic microorganisms. As a result, the pretreated CS achieved 19.1% higher biomethane yield, 9.1% higher volatile solid removal rate, and 3 days shorter digestion time. The mass balance and microbial community succession analysis indicated that the pretreatment reinforced the biomethane conversion from carbohydrate, which was attributed to the rapid enrichment of hydrolytic acidification bacteria (g__unclassified_o__Bacteroidales) (33.2%) and mixotrophic archaea (Methanosarcina) (72.3%). Meanwhile, the activity of cellulase and xylanase was enhanced up to 23.7% and 66.7%. Metagenomic analysis revealed that the combined pretreatment of CS promoted methanogenesis by enhancing various CAZymes secretion (such as oligosaccharide-degrading enzymes), and functional genes expression of hydrolytic, acidification and acetate-methane pathways at days 1–5. The study indicated that the combined pretreatment could influence microbial composition and function by changing the physicochemical properties of the CS, thereby improving methanogenic performance. [Display omitted] • Effect of urea-hydrothermal pretreatment of corn stover was investigated on anaerobic digestion. • Microbial community succession rate was enhanced by the combined pretreatment. • The effect of pretreatment on the hydrolases activity and functional genes were examined. • AcEtate-methane pathway was largely activated by the combined pretreatment. [ABSTRACT FROM AUTHOR]

The practical applications of Pt-based nano-catalysts in oxygen reduction reaction (ORR) have been seriously restricted by their high cost and poor durability. Therefore, it is significantly desirable to explore high active, non-noble metal and low-cost electrocatalysts for ORR. Herein, a series of nickel salts [NiNH2SO3, Ni(NO3)2, NiSO4, NiAc2, NiCl2, and Ni(acac)2] doped MnO2 octahedral molecular sieves (Ni-OMS-2) nanomaterials are successfully synthesized by a simple hydrothermal reaction and used as cathodic ORR electrocatalyst. We also demonstrate that nickel salt has a significant influence on the porous structure, morphology and ORR performance. Notably, comparing with other nickel salts-doped Ni-OMS-2 catalysts, the resulting Ni-OMS-2 with NiNH2SO3 dopant exhibits impressive electrocatalytic performance toward ORR in alkaline (0.1 M KOH), with a more positive Eonset (0.866 V) and E1/2 (0.792 V), as well as high limited diffusion current (5.03 mA/cm2), respectively. Moreover, it displays superior long-term stability and methanol tolerance than that of commercial Pt/C, and the ORR process follows an ideal 4e− transfer pathway. Such outstanding ORR performance primarily contributes to the well-defined one-dimensional nanorods and nickel salts doping, which are in favor of promoting electron transfer, active sites exposure and intermediates absorption during the catalytic process. [ABSTRACT FROM AUTHOR]

Allatostatin C (PISCF/AST) is a neuropeptide gene that affects juvenile hormone (JH) synthesis in the corpora allata. Juvenile hormone acid O-methyltransferase (JHAMT) is a key gene in the JH biosynthetic pathway. In this study, two genes encoding DaAST and DaJHAMT were cloned. Both DaAST and DaJHAMT were expressed in the larvae, pupae and adults of Chinese white pine beetle (Dendroctonus armandi), and highly expressed in the head and the gut. The expression of the two genes was induced by JH analog (JHA) methoprene and the functions of the two genes were then investigated by RNAi. Considering the role of hormones in metamorphosis, JHA significantly induced DaAST and DaJHAMT in the larval stage. DaAST knockdown in larvae, pupae and adults significantly increased the DaJHAMT mRNA levels. Moreover, knockdown of DaAST instead of DaJHAMT increased pupae mortality and the abnormal rate of emergence morphology and reduced emergence rates. However, knockdown of DaJHAMT instead of DaAST significantly reduced frontalin biosynthesis in adult males. The results showed that DaAST acts as an allatostatin and inhibits JH biosynthesis, and that JHAMT is a key regulatory enzyme for JH synthesis in the D. armandi. [ABSTRACT FROM AUTHOR]

• BITC can control gray mold and natural decay of strawberry fruits. • BITC inhibited spore germination and vegetative growth of B. cinerea. • BITC caused the damage of plasma membrane and ROS accumulation in B. cinerea. • BITC interfered with the phytotoxin synthesis and pathogenesis of B. cinerea. Gray mold, caused by Botrytis cinerea , is an important cause of postharvest loss of strawberry fruit. In the present study, we found that benzyl-isothiocyanate (BITC), a natural compound widely existing in cruciferous vegetables with anti-cancer effect, was effective in controlling postharvest gray mold of strawberry fruit, and also strongly inhibited the natural decay of strawberry. The mode of action of BITC against B. cinerea was mainly attributed to its direct inhibition on spore germination. BITC application could disrupt the plasma membrane integrity and induce ROS accumulation in the spores of B. cinerea , eventually leading to cell death. To further investigate the inhibitory mechanisms of BITC against B. cinerea , we conducted a comparative transcriptome analysis. Most of the differentially expressed genes (DEGs) participated in the metabolism of carbohydrate, lipid and amino acid, the genetic information processing, as well as the biosynthesis of other secondary metabolites. This study provides a safe and promising method to control strawberry postharvest diseases based on BITC, and gets insight into the antimicrobial mechanism of BITC. [ABSTRACT FROM AUTHOR]

Machine Learning technologies have obtained breakthrough in various fields, and medical information extraction has also successfully made great progress through deep learning methods. However, entity relationship overlap is a key issue and challenge in the field of medical entity relationship extraction. Hence, we propose an intelligent extraction method for Chinese medicine entity relationship through improving graph neural network and structure optimization strategy. We optimize model structure and introduce global pointer network. The sentence feature information is captured by attention mechanism and Bi-Long Short Term Memory (LSTM). Grammatical relations between entities are parsed using Graph Convolution Network (GCN) layer. Finally, multiple decoders are used for joint extraction of entity relations through the global pointer network. The model learns the graph structure data by GCN, while the challenge of entity relationship overlap is solved through using the pointer network. The experiments demonstrate that the model achieves 83.77% in terms of F1 value, which is better than other baseline models. [ABSTRACT FROM AUTHOR]

The Chinese white pine beetle, Dendroctonus armandi Tsai & Li (Coleoptera: Curculionidae, Scolytinae), is considered the most destructive forest pest in the Qinling and Bashan Mountains of China. In recent years, winter temperature has dropped in these regions, and extremely low temperatures are hard to survive for insects. Cold hardiness becomes a crucial strategy because temperature change often leads to fluctuations in insect abundance, and the metabolism rate is a key index of resistance to cold in overwintering insects. Therefore, we investigated the relationship between the change in respiratory rate and the activity of metabolism‐related mitochondrial enzymes in D. armandi larvae under cold conditions. We found that the respiratory rate decreased, and it was matched with the activity of glutamate dehydrogenase, aconitase, and lipase during overwintering. Among the various test times under cold conditions, the respiratory rate also decreased with decreasing temperature and increased under very low temperatures. At all cold stress periods, glutamate dehydrogenase and lipase showed increased activity at higher temperatures and decreased activity under lower temperatures, but the activity of NAD‐malic enzyme, NADP‐malic enzyme, mitochondrial isocitrate dehydrogenase, and aconitase were contrary. Under all low temperatures, the activity of enzymes – except for NADP‐malic enzyme, glutamate dehydrogenase, and lipase – increased in short‐term cold stress and decreased in long‐term cold stress at 4, 0, −4, −6, −8, and −10 °C. However, at −2 °C, the activity of enzymes showed a decreasing trend in short‐term treatments and an increasing trend in long‐term treatments, except for mitochondrial isocitrate dehydrogenase. The results not only improve our understanding of the metabolic mechanism of cold adaptation in D. armandi, but also provide an important experimental basis for further study and biological pest control. [ABSTRACT FROM AUTHOR]

• CD tended to generate CO 2 , FD and ND were apt to produce the syngas. • CD was not a suitable OC for syngas production. • The mass of 30.0 g and 20.0 g at 900 °C were optimum for FD and ND respectively. • ND was the most promising OC for syngas production among the three. • ND had the highest syngas purity of 90.59% and the H 2 /CO ratio of ca. 2.0. Syngas is an indispensable chemical raw material, which also can provide heat and power. Chemical looping reforming (CLR) with biofuels is one prospective method to produce syngas. M x O y of 20 wt% (CuO, NiO and Fe 2 O 3) supported on dolomite were prepared by the wet impregnation method used as the oxygen carriers (OCs) for syngas production in the CLR process with toluene in the lab-scale fixed bed reactor. The effects of the reduced temperature in FR and mass of OCs on the fuel conversion, syngas production and OCs utilization were studied. The study found that CuO/dolomite (CD) tended to generate CO 2 , while Fe 2 O 3 /dolomite (FD) and NiO/dolomite (ND) were appropriate to syngas production. Although CD achieved the highest oxygen effective conversion of 95.90% at 950 °C and the best selectivity for CO 2 , it was not a suitable OC for syngas production in CLR process since the cold gas efficiency, syngas yield and syngas purity for CD remained lowest under different reaction conditions. FD manifested the best performance at 900 °C with 30.0 g, exhibiting the highest cold gas efficiency and syngas yield of 54.23% and 1.16 Nm3/L, and the corresponding syngas purity was 73.86%. The selection of temperature and mass of FD played a key role in the quality control of syngas. Low syngas purity and rapid deactivation in cyclic tests were main barriers for FD to behave as an excellent OC in the CLR process. Furthermore, ND was the most ideal OC of the three for syngas production with the optimum condition being at 900 °C with 20.0 g, the corresponding cold gas efficiency, syngas yield and syngas purity were 39.30%, 0.93 Nm3/L and 90.59% respectively. ND exhibited the highest syngas purity of the three, and the satisfied H 2 /CO ratios (around 2.0) were achieved under different reaction conditions. [ABSTRACT FROM AUTHOR]