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Water-lubricated material is the fundamental ingredient of a water-lubricated bearing (WLB), of which the friction and wear properties directly affect the working performance and service life of a WLB. We designed a micron-scale stripe texture and fabricated a negative microtexture mold by femtosecond laser etching. The microtextures were fabricated onto the surface of Thordon and polyurethane water-lubricated materials by a precision thermoforming machine. Tribological tests showed that the microstripe texture on water-lubricated materials had lower friction and wear properties than that on pristine surface materials. The results demonstrated that the presence of the microstripe texture effectively improved the friction and anti-wear properties of the water-lubricated materials. This study provides a new idea for the design and preparation of water-lubricated materials with good water-lubricating and anti-wear properties. [ABSTRACT FROM AUTHOR]

Many insects, including the Plutella xylostella (L.), have developed varying degrees of resistance to many insecticides, including Bacillus thuringiensis (Bt) toxins, the bioinsecticides derived from Bt. The polycalin protein is one of the potential receptors for Bt toxins, and previous studies have confirmed that the Cry1Ac toxin can bind to the polycalin protein of P. xylostella, but whether polycalin is associated with the resistance of Bt toxins remains controversial. In this study, we compared the midgut of larvae from Cry1Ac-susceptible and -resistant strains, and found that the expression of the Pxpolycalin gene was largely reduced in the midgut of the resistant strains. Moreover, the spatial and temporal expression patterns of Pxpolycalin showed that it was mainly expressed in the larval stage and midgut tissue. However, genetic linkage experiments showed that the Pxpolycalin gene and its transcript level were not linked to Cry1Ac resistance, whereas both the PxABCC2 gene and its transcript levels were linked to Cry1Ac resistance. The larvae fed on a diet containing the Cry1Ac toxin showed no significant change in the expression of the Pxpolycalin gene in a short term. Furthermore, the knockout of polycalin and ATP-binding cassette transporter subfamily C2 (ABCC2) genes separately by CRISPR/Cas9 technology resulted in resistance to decreased susceptibility to Cry1Ac toxin. Our results provide new insights into the potential role of polycalin and ABCC2 proteins in Cry1Ac resistance and the mechanism underlying the resistance of insects to Bt toxins. [ABSTRACT FROM AUTHOR]

Methionine aminopeptidases (MetAPs) catalyze the cleavage of the N-terminal initiator methionine (iMet) in new peptide chains and arylamides, which is essential for protein and peptide synthesis. MetAP is differentially expressed in two diamondback moth (DBM; Plutella xylostella) strains: the G88 susceptible strain and the Cry1S1000 strain, which are resistant to the Bt toxin Cry1Ac, implicating that MetAP expression might be associated with Bt resistance. In this study, we identified and cloned a MetAP gene from DBMs, named PxMetAP1, which has a CDS of 1140 bp and encodes a 379 amino acid protein. The relative expression of PxMetAP1 was found to be ~2.2-fold lower in the Cry1S1000 strain compared to that in the G88 strain. PxMetAP1 presents a stage- and tissue-specific expression pattern, with higher levels in the eggs, adults, integument, and fatbody of DBMs. The linkage between PxMetAP1 and Cry1Ac resistance is verified by genetic linkage analysis. The knockout of PxMetAP1 in G88 by CRISPR/Cas9 leads to a ~5.6-fold decrease in sensitivity to the Cry1Ac toxin, further supporting the association between the PxMetAP1 gene and Bt tolerance. Our research sheds light on the role of MetAP genes in the development of Bt tolerance in P. xylostella and enriches the knowledge for the management of such a cosmopolitan pest. [ABSTRACT FROM AUTHOR]

In this paper, the initial neutral atmospheric parameters, background ionospheric parameters and geomagnetic field parameters of the ionosphere are obtained by NRLMSISE-00 model, IRI-2016 model and IGRF-13 model, respectively. Considering the neutral gas diffusion process, ion chemical reaction and plasma diffusion process, a three-dimensional dynamic model of chemical substances released by rocket plume disturbing the ionosphere is constructed. The influence of the disturbance on the echo path of high frequency radio waves with different incident frequencies is simulated by using three-dimensional digital ray-tracing technology. Using this model, the process of ionospheric disturbance caused by the main chemical substances H2 and H2O in the rocket plume under three different release conditions: fixed-point release at 300 km, vertical path at 250–350 km and parabolic path at 250–350 km, and the influence of the ionospheric cavity on the radio wave propagation of high frequency radio waves at different frequencies are simulated. The main purpose of the article is to focus on the effect of the cavity generated by the rocket exhaust on the propagation of radio waves. It mainly studies the perturbation effect on the ionosphere under different release conditions, considers the neutral gas diffusion process, ion chemical reaction and plasma diffusion process, and establishes the three-dimensional dynamics of the ionospheric electron density and the spatiotemporal distribution of the plume plasma learning model. Finally, the three-dimensional ray-tracing algorithm is used to simulate the propagation path of the radio wave through the disturbance area. We considered three different release conditions, including fixed-point release, vertical path and parabolic path. The ionospheric disturbances produced by these different releases are compared and analyzed, and their effects on the propagation path of radio waves are studied. [ABSTRACT FROM AUTHOR]

In this paper, the ionospheric disturbances of CO2, which is released by rocket exhaust plumes, was simulated. The effect of this disturbance on the propagation of high-frequency (HF) radio waves at different incident frequencies was also simulated by using three-dimensional digital ray tracing technique. The results show that CO2 can effectively dissipate the background electrons and form ionospheric holes after being released in the ionosphere. At the peak height of ionospheric electron density (about 300 km), the electrons are dissipated fastest and the radius of ionospheric hole is also largest. This is due to the fact that the diffusion coefficient of CO2 usually increases with height while the electron density just increases before reaching its peak height and then decreases with height, and the chemical reaction rate between ions and CO2 also becomes largest at the peak height of electron density (about 300 km). Around 100 s after the release of CO2, when the radio waves at a frequency of 8 MHz pass through the ionosphere with an elevation range of 85~95°, the "secondary focusing effect" can occur, and we believe that this is due to the reflection of HF shortwaves on the walls of the ionospheric holes. With time going on, this phenomenon disappears at 300 s and only one focus is left at this time. For the HF shortwaves at same incident frequency, the focusing effect of waves displays a weakening trend with time increasing, and the height of focus center also ascends gradually. At the same time after CO2 releasing, with the increasing of radio waves frequency, the focusing effect also becomes weaker and the focus center displays an ascending trend. [ABSTRACT FROM AUTHOR]

Simple Summary: Plutella xylostella is a very serious pest to cruciferous vegetables. At present, the control methods used are mainly traditional insecticides and the cultivation of Bt crops. However, with the long-term and large-scale use of insecticides, the diamondback moth has developed strong resistance to many kinds of insecticides and Bt crops. The Cry1S1000 strain of P. xylostella used here is a strain with more than 8000 times resistance to Bt Cry1Ac protoxin. In this paper, we used transcriptome sequencing to determine the midgut transcriptome of the G88-susceptible strain, Cry1S1000-resistant strain and its corresponding toxin-induced strains to find more genes related to Bt resistance. Our results will provide a reference for optimizing the control strategy of diamondback moth resistance and improving the control efficiency of biopesticides and Bt crops. The diamondback moth, Plutella xylostella, is a lepidopteran insect that mainly harms cruciferous vegetables, with strong resistance to a variety of agrochemicals, including Bacillus thuringiensis (Bt) toxins. This study intended to screen genes associated with Bt resistance in P. xylostella by comparing the midgut transcriptome of Cry1Ac-susceptible and -resistant strains together with two toxin-treated strains 24 h before sampling. A total of 12 samples were analyzed by BGISEQ-500, and each sample obtained an average of 6.35 Gb data. Additionally, 3284 differentially expressed genes (DEGs) were identified in susceptible and resistant strains. Among them, five DEGs for cadherin, 14 for aminopeptidase, zero for alkaline phosphatase, 14 for ATP binding cassette transport, and five heat shock proteins were potentially involved in resistance to Cry1Ac in P. xylostella. Furthermore, DEGs associated with "binding", "catalytic activity", "cellular process", "metabolic process", and "cellular anatomical entity" were more likely to be responsible for resistance to Bt toxin. Thus, together with other omics data, our results will offer prospective genes for the development of Bt resistance, thereby providing a brand new reference for revealing the resistance mechanism to Bt of P. xylostella. [ABSTRACT FROM AUTHOR]

Mitigation measures and control strategies relating to the novel coronavirus disease 2019 (COVID-19) have been widely applied in many countries to reduce the transmission of this pandemic disease. China was the first country to implement a strong lockdown policy to control COVID-19 when countries worldwide were struggling to manage COVID-19 cases. However, lockdown causes numerous changes to air-quality patterns due to the low amount of traffic and the decreased human mobility it results in. To study the impact of the strict control measures of the new COVID-19 epidemic on the air quality of Hubei in early 2020, the air-quality monitoring data of Hubei's four cities, namely Huangshi, Yichang, Jingzhou, and Wuhan, from 2019 to 2021, specifically 1 January to 30 August, was examined to analyze the characteristics of the temporal and spatial distribution. All air-quality pollutants decreased during the active-COVID-19 period, with a maximum decrease of 26% observed in PM 10 , followed by 23% of PM 2.5 , and a minimum decrease of 5% observed in O 3 . Changes in air pollutants from 2017 to 2021 were also compared, and a decrease in all pollutants through to 2020 was found. The air-quality index (AQI) recorded an increase of 2% post-COVID-19, which shows that air quality will worsen in future, but it decreased by 22% during the active-COVID-19 period. A path analysis model was developed to further understand the relationship between the AQI and air-quality patterns. This path analysis shows a strong correlation between the AQI and PM 10 and PM 2.5 , however its correlation with other air pollutants is weak. Regression analysis shows a similar pattern of there being a strong relationship between AQI and PM 10 ( r 2 = 0.97) and PM 2.5 ( r 2 = 0.93). Although the COVID-19 pandemic had numerous negative effects on human health and the global economy, it is likely that the reduction in air pollution and the significant improvement in ambient air quality due to lockdowns provided substantial short-term health benefits. The government must implement policies to control the environmental issues which are causing poor air quality in post-COVID-19. [ABSTRACT FROM AUTHOR]

This study aims to investigate the relationship of firm performance and corporate social responsibility reporting and the moderating role of a firm's life cycle stages in Chinese listed companies. We used the sample of all A-share listed firms on the Shanghai and Shenzhen stock exchanges for the period 2010 to 2020. The authors used pooled ordinary least squares (OLS) regression as a baseline methodology. Our regression results show that positive Corporate social responsibility (CSR) activity significantly reduces the performance of the firm. In addition, the negative link between positive Corporate social responsibility and a firm's performance is more pronounced for firms in mature life cycle stages. Our results are robust to alternative proxy measures of ROA for firm performance, corporate social responsibility reporting, and life cycle stages. To control the possible problem of endogeneity, we use a one-year lag and 2SLS least squares regression. We find that firm performance has a statistically significant influence on CSR reporting. Moreover, we see that firms with high performance are more likely to report CSR activities than low-performance firms. Additionally, six out of ten control variables (Independent Director, Board Shares, State Owned Enterprise, Board Meeting, Chief executive officer Duality, and Firm Growth) have positive influences on CSR reporting. These findings hold for a set of robustness tests. Our results have implications for the development of CSR reporting in developing countries such as China. Our research suggests that, in China, firms with better financial performance undertake more CSR reporting. This paper contributes to the existing literature by investigating the effect of firm performance on CSR reporting and the moderating role of a firm's life cycle stages in Chinese listed companies. Additionally, this paper enriches the current literature on CSR reporting and highlights the importance of a firm's financial performance for better environmental performance and reporting. [ABSTRACT FROM AUTHOR]

The plant-specific transcription factor gene family, YABBY, belongs to the subfamily of zinc finger protein superfamily and plays an essential regulatory role in lateral organ development. In this study, nine YABBY genes were identified in the pineapple genome. Seven of them were located on seven different chromosomes and the remaining two were located on scaffold 1235. Through protein structure prediction and protein multiple sequence alignment, we found that AcYABBY3, AcYABBY5 and AcYABBY7 lack a C2 structure in their N-terminal C2C2 zinc finger protein structure. Analysis of the cis-acting element indicated that all the seven pineapple YABBY genes contain multiple MYB and MYC elements. Further, the expression patterns analysis using the RNA-seq data of different pineapple tissues indicated that different AcYABBYs are preferentially expressed in various tissues. RT-qPCR showed that the expression of AcYABBY2, AcYABBY3, AcYABBY6 and AcYABBY7 were highly sensitive to abiotic stresses. Subcellular localization in pineapple protoplasts, tobacco leaves and Arabidopsis roots showed that all the seven pineapple YABBY proteins were nucleus localized. Overexpression of AcYABBY4 in Arabidopsis resulted in short root under NaCl treatment, indicating a negative regulatory role of AcYABBY4 in plant resistance to salt stress. This study provides valuable information for the classification of pineapple AcYABBY genes and established a basis for further research on the functions of AcYABBY proteins in plant development and environmental stress response. [ABSTRACT FROM AUTHOR]

Chromatin remodeling complex orchestrates numerous aspects of growth and development in eukaryotes. SWI2/SNF2-Related 1 chromatin remodeling complex (SWR1-C) is a member of the SWI/SNF ATPase-containing chromatin remodeling complex responsible for the exchange of H2A for H2A.Z. In plants, SWR1-C plays a crucial role by transcriptionally regulating numerous biological and developmental processes. However, SWR1-C activity remains obscure in pineapple. Here, we aim to identify the SWR1-C subunits in pineapple. By genome-wide identification, we found a total of 11 SWR1-C subunits in the pineapple. The identified SWR1-C subunits were named and classified based on the sequence similarity and phylogenetic analysis. RNA-Seq analysis showed that pineapple SWR1-C subunits are expressed differentially in different organs and at different stages. Additionally, the qRT-PCR of pineapple SWR1-C subunits during abiotic stress exposure showed significant changes in their expression. We further investigated the functions of pineapple SWR1 COMPLEX 6 (AcSWC6) by ectopically expressing it in Arabidopsis. Interestingly, transgenic plants ectopically expressing AcSWC6 showed susceptibility to fungal infection and enhanced resistance to salt and osmotic stress, revealing its involvement in biotic and abiotic stress. Moreover, the complementation of mutant Arabidopsisswc6 by pineapple SWC6 suggested the conserved function of SWC6 in plants. [ABSTRACT FROM AUTHOR]

Obesity and its common association with type 2 diabetes, dyslipidemia, and cardiovascular diseases are worldwide epidemics. Currently, to prevent or treat obesity and associated metabolic disorders, herbal dietary supplements or medicines have attracted more and more attention owing to their relative effectiveness with fewer significant side effects. We investigate the therapeutic effects and underlying mechanisms of Plantago asiatica L. seed extract (PSE) on obesity and associated metabolic disorders in high-fat (HF) diet-induced mice. Our results displayed that PSE did not modify food intake or body weight but decreased abdominal white adipose tissue ratio, white/brown adipocyte size, serum total cholesterol, triglyceride (TG), low density lipoprotein cholesterol, free fatty acid, and hepatic TG concentrations when compared with the HF group. The levels of fasting blood glucose and glucose tolerance were improved in the PSE group when compared with the HF group. Furthermore, PSE upregulated mRNA expressions of peroxisome proliferator activated receptors (PPARs) and target genes related to fatty acid metabolism and energy expenditure in liver and adipose tissue of obese mice when compared with the HF group. PSE treatment effectively improved lipid and glucose metabolism in HF diet-induced obese mice. These effects might be attributed to the upregulation of PPAR signaling., Competing Interests: The authors declare no conflict of interest.