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Ovarian follicular GCs are strongly implicated in the growth, development, and atresia of ovarian follicles. The Wnt/β-catenin and Notch signaling pathways participate in GC proliferation, differentiation, apoptosis, and steroid hormone production during follicular development. However, the crosstalk between Wnt and Notch signaling in GCs remains unclear. This study investigated this crosstalk and the roles of these pathways in apoptosis, cell cycle progression, cell proliferation, and steroid hormone secretion in bovine follicular GCs. The interaction between β-catenin and Notch2 in GCs was assessed by overexpressing CTNNB1, which encodes β-catenin. The results showed that inhibiting the Notch pathway by Notch2 silencing in GCs arrested the cell cycle, promoted apoptosis, reduced progesterone (P4) production, and inhibited the Wnt2-mediated Wnt/β-catenin pathway in GCs. IWR-1 inhibited Wnt2/β-catenin and Notch signaling, reduced GC proliferation, stimulated apoptosis, induced G1 cell cycle arrest, and reduced P4 production. CTNNB1 overexpression had the opposite effect and increased 17β-estradiol (E2) production and Notch2 protein expression. Co-immunoprecipitation assays revealed that Notch2 interacted with β-catenin. These results elucidate the crosstalk between the Wnt/β-catenin and Notch pathways and the role of these pathways in bovine follicular GC development.

Cross-talk between competitive endogenous RNAs (ceRNAs) may play a critical role in revealing potential mechanism of bovine follicular cysts. Ovarian cyst has always been an intractable scientific problem and has led to considerable economic losses to bovine breeding industry. However, its pathogenesis and molecular mechanisms are still not well understood. Here, this study aimed to investigate the role of non-coding RNAs (ncRNAs) and the ceRNA networks in bovine follicular cyst. Whole transcriptome sequencing of bovine follicular granulosa cells (GCs) was conducted to obtain the expression profiles of mRNAs, lncRNAs and miRNAs. The results for the identified expressions of 8,003 mRNAs, 579 lncRNAs and 205 miRNAs were often altered between cystic and normal follicular GCs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed on these differentially expressed mRNAs. Furthermore, the ceRNA network combining mRNAs, miRNAs, and lncRNAs using several bioinformatics methods based on co-expression analysis between the differentially expressed RNAs was conducted. Finally, the lncRNA NONBTAT027373.1-miR-664b-HSD17B7 pathway was verified by dual-luciferase reporting assay and RNA binding protein immunoprecipitation (RIP) assay. LncRNA NONBTAT027373.1 sponged miR-664b in GCs and prevented miR-664b from binding to the HSD17B7 3'-UTR. These results indicated that genes and lncRNAs related to steroid hormone synthesis and energy metabolism could play important roles in the formation of bovine cystic follicles through the ceRNA mechanism and represent candidate targets for further research. This can be used as a practical guideline for promoting healthy and highly efficient development in the bovine industry.

In order to solve the problems of honeycomb sandwich structure electromagnetic wave absorbing composites with easy delamination, low strength, and a narrow absorption frequency band, a double-layer honeycomb 3D woven electromagnetic wave absorbing composite was designed and prepared. CST electromagnetic simulations and mechanical finite element simulations were combined with experimental analysis, respectively. The electromagnetic wave absorption properties and bending properties of the double-layer honeycomb 3D woven electromagnetic wave absorbing composite were revealed, and the electromagnetic wave absorption mechanism was elucidated. The results show that the lowest peak of reflection loss obtained from both simulation and experiment of electromagnetic wave absorption property occurs in the X-band with the values of 10.78 GHz and 9.28 GHz, respectively. The lowest reflection loss is −24.35 dB and −23.5 dB, respectively. The simulation results were in good agreement with the experimental results. The maximum loads obtained from simulation and experiment for the bending property were 2696.28 N and 2271.07 N, respectively. There is no obvious delamination damage to the yarn, and the material has good resistance to delamination. The structural-functional integration of load-bearing and electromagnetic wave absorption in double-layer honeycomb 3D woven electromagnetic wave absorbing composite will have great development potential in civil and military fields. [ABSTRACT FROM AUTHOR]

Noise pollution is one of the serious environmental pollutions. In recent years, the preparation of sound absorption composites using natural fibers as reinforcement material has attracted much attention. Sugarcane bagasse is a by-product of sugarcane. In order to improve the utilization rate of sugarcane bagasse, enrich and expand the application field of its renewable resources, sugarcane bagasse as a reinforcement material, and polycaprolactone as a matrix material are used to prepare sugarcane bagasse/polycaprolactone sound absorption composites by hot press molding technology to analyze the sound absorption performance. The sound absorption mechanism of the sugarcane bagasse sound absorption composites is revealed. First, the structural characteristics of sugarcane bagasse were characterized, and the relationship between its structure and sound absorption performance was analyzed. Second, the effects of sugarcane bagasse length, mass fraction, hot pressing pressure, hot pressing time, and hot pressing temperature on the sound absorption performance were investigated by one-factor analysis. The results show that when the length of sugarcane bagasse was 1.0 mm, the mass fraction was 35%, the hot pressing pressure was 12 MPa, the hot pressing time was 20 min, and the hot pressing temperature was 130°C, the average sound absorption coefficient was 0.38, the noise reduction coefficient was 0.31, and the maximal sound absorption coefficient was 0.80. This study provides an experimental and theoretical basis for the research and development of sound absorption composites made of sugarcane bagasse, and provides a new solution for the recycling of sugarcane bagasse. [ABSTRACT FROM AUTHOR]

The N6‐methyladenosine (m6A) modification of RNA has been reported to remodel gene expression in response to environmental conditions; however, the biological role of m6A in social insects remains largely unknown. In this study, we explored the role of m6A in the division of labour by worker ants (Solenopsis invicta). We first determined the presence of m6A in RNAs from the brains of worker ants and found that m6A methylation dynamics differed between foragers and nurses. Depletion of m6A methyltransferase or chemical suppression of m6A methylation in foragers resulted in a shift to 'nurse‐like' behaviours. Specifically, mRNAs of dopamine receptor 1 (Dop1) and dopamine transporter (DAT) were modified by m6A, and their expression increased dopamine levels to promote the behavioural transition from foragers to nurses. The abundance of Dop1 and DAT mRNAs and their stability were reduced by the inhibition of m6A modification caused by the silencing of Mettl3, suggesting that m6A modification in worker ants modulates dopamine synthesis, which regulates labour division. Collectively, our results provide the first example of the epitranscriptomic regulation of labour division in social insects and implicate m6A regulatory mechanism as a potential novel target for controlling red imported fire ants. [ABSTRACT FROM AUTHOR]

The insect gustatory system participates in identifying potential food sources and avoiding toxic compounds. During this process, gustatory receptors (GRs) recognize feeding stimulant and deterrent compounds. However, the GRs involved in recognizing stimulant and deterrent compounds in the red imported fire ant, Solenopsis invicta, remain unknown. Therefore, we conducted a study on the genes SinvGR1, SinvGR32b, and SinvGR28a to investigate the roles of GRs in detecting feeding stimulant and deterrent compounds. In this current study, we found that sucrose and fructose are feeding stimulants and the bitter compound quinine is a feeding deterrent. The fire ant workers showed significant behavior changes to avoid the bitter taste in feeding stimulant compounds. Reverse transcription quantitative real‐time polymerase chain reaction results from developmental stages showed that the SinvGR1, SinvGR32b, and SinvGR28a genes were highly expressed in fire ant workers. Tissue‐specific expression profiles indicated that SinvGR1, SinvGR32b, and SinvGR28a were specifically expressed in the antennae and foreleg tarsi of workers, whereas SinvGR32b gene transcripts were also highly accumulated in the male antennae. Furthermore, the silencing of SinvGR1 or SinvGR32b alone and the co‐silencing of both genes disrupted worker stimulation and feeding on sucrose and fructose. The results also showed that SinvGR28a is required for avoiding quinine, as workers with knockdown of the SinvGR28a gene failed to avoid and fed on quinine. This study first identified stimulant and deterrent compounds of fire ant workers and then the GRs involved in the taste recognition of these compounds. This study could provide potential target gustatory genes for the control of the fire ant. [ABSTRACT FROM AUTHOR]

Juvenile hormone (JH) acts in the regulation of caste differentiation between queens and workers (i.e., with or without reproductive capacity) during vitellin synthesis and oogenesis in social insects. However, the regulatory mechanisms have not yet been elucidated. Here, we identified a highly expressed microRNA (miRNA), miR‐1175‐3p, in the red imported fire ant, Solenopsis invicta. We found that miR‐1175‐3p is prominently present in the fat bodies and ovaries of workers. Furthermore, miR‐1175‐3p interacts with its target gene, broad‐complex core (Br‐C), in the fat bodies. By utilizing miR‐1175‐3p agomir, we successfully suppressed the expression of the Br‐C protein in queens, resulting in reduced vitellogenin expression, fewer eggs, and poorly developed ovaries. Conversely, decreasing miR‐1175‐3p levels led to the increased expression of Br‐C and vitellogenin in workers, triggering the "re‐development" of the ovaries. Moreover, when queens were fed with JH, the expression of miR‐1175‐3p decreased, whereas the expression of vitellogenin‐2 and vitellogenin‐3 increased. Notably, the suppression of fertility in queens caused by treatment with agomir miR‐1175‐3p was completely rescued by the increased vitellogenin expression induced by being fed with JH. These results suggest the critical role of miR‐1175‐3p in JH‐regulated reproduction, shedding light on the molecular mechanism underlying miRNA‐mediated fecundity in social insects and providing a novel strategy for managing S. invicta. [ABSTRACT FROM AUTHOR]

In this paper, gahnite (ZnAl2 O4) was prepared with solid phase reaction by ZnO and Al2 O3 as raw materials. The micro-structure change of ZnAl2 O4 was researched when ZnO/Al2 O3 molar ratios were 1.0 : 0. 9, 1.0 : 1.0 and 1.0: 1.1, respectively. In addition, the effect of ZnAl2 O4 on properties of high alumina castables were studied. The results show that when the molar ratio of ZnO to Al2 O3 is 1.0: 0.9, due to the excessive ZnO, it volatilizes because of the removal of O2- to produce liquid phase, and the surface of ZnAl2 O4 particles is microporous structure. When the molar ratio of ZnO and Al2 O3 is 1.0: 1.0 (standard molar ratio), the surface of ZnAl2 O4 particles with standard molar ratio is smooth. The lattice strain value (0.085 86) of standard molar ratio ZnAl2 O4 is the smallest, which can capture more manganese ions and iron ions in steel slag. When the molar ratio of ZnO to Al2 O3 is 1.0: 1.1, the surface of ZnAl2 O4 particles is rough. The high alumina castable with standard molar ratio ZnAl2 O4 has denser structure, highest strength and best slag resistance. [ABSTRACT FROM AUTHOR]