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Objective In the actual metro construction, it is often necessary to lay turnouts on large-slope sections due to planning and construction constraints, land conservation or topographical limitations. However, it is found through practical application that the large-slope turnout structure leads to poor train stability and ride comfort during operation, thus an investigation on the factors influencing vehicle passing performance through large-slope metro turnouts is required. Method Based on multi-body dynamics theory, using simulation analysis software and taking the No.9 turnout installed on a 30‰ slope as research object, a coupled vehicle-turnout multi-body dynamics model is established. The dynamics performance indicators (including wheel-rail interaction, safety indicators, and stability indicators) of single vehicle passing through large-slope turnout at different operating speeds and friction coefficients are compared，aiming to analyze the impact of various factors on the vehicle passing performance through large-slope metro turnouts. Result & Conclusion It is revealed through simulation research that the impact of operating speed on wheel-rail interaction, stability indicators, and safety indicators is independent of the slope direction during vehicle passing turnouts. When a vehicle passes through turnouts on uphill and downhill slopes, the influence trends of operating speed on the dynamics indicators are consistent, with a more significant impact when going downhill; the friction coefficient greatly affects the wheel-rail dynamic interaction and the vehicle lateral acceleration. As the friction coefficient increases, the wheel-rail interaction force decreases, the carbody vertical acceleration shows no significant change, and the lateral acceleration increases significantly, with a more pronounced effect when going downhill. Therefore, certain strengthening and protective measures should be taken when vehicle going downhill.

Cold stress affects the seed germination and early growth of winter rapeseed, leading to yield losses. We employed transmission electron microscopy, physiological analyses, metabolome profiling, and transcriptome sequencing to understand the effect of cold stress (0 °C, LW) on the cotyledons of cold-tolerant (GX74) and -sensitive (XY15) rapeseeds. The mesophyll cells in cold-treated XY15 were severely damaged compared to slightly damaged cells in GX74. The fructose, glucose, malondialdehyde, and proline contents increased after cold stress in both genotypes; however, GX74 had significantly higher content than XY15. The pyruvic acid content increased after cold stress in GX74, but decreased in XY15. Metabolome analysis detected 590 compounds, of which 32 and 74 were differentially accumulated in GX74 (CK vs. cold stress) and XY15 (CK vs. cold stressed). Arachidonic acid and magnoflorine were the most up-accumulated metabolites in GX74 subjected to cold stress compared to CK. There were 461 and 1481 differentially expressed genes (DEGs) specific to XY15 and GX74 rapeseeds, respectively. Generally, the commonly expressed genes had higher expressions in GX74 compared to XY15 in CK and cold stress conditions. The expression changes in DEGs related to photosynthesis-antenna proteins, chlorophyll biosynthesis, and sugar biosynthesis-related pathways were consistent with the fructose and glucose levels in cotyledons. Compared to XY15, GX74 showed upregulation of a higher number of genes/transcripts related to arachidonic acid, pyruvic acid, arginine and proline biosynthesis, cell wall changes, reactive oxygen species scavenging, cold-responsive pathways, and phytohormone-related pathways. Taken together, our results provide a detailed overview of the cold stress responses in rapeseed cotyledons. [ABSTRACT FROM AUTHOR]

The application of phosphorus-solubilizing bacteria is an effective method for increasing the available phosphorus content and inhibiting wheat uptake of heavy metals. However, further research is needed on the mechanism by which phosphorus-solubilizing bacteria inhibit cadmium (Cd) uptake in wheat roots and its impact on the expression of root-related genes. Here, the effects of strain Klebsiella aerogenes M2 on Cd absorption in wheat and the expression of root-related Cd detoxification and immobilization genes were determined. Compared with the control, strain M2 reduced (64.1–64.6%) Cd uptake by wheat roots. Cd fluorescence staining revealed that strain M2 blocked the entry of exogenous Cd into the root interior and enhanced the immobilization of Cd by cell walls. Forty-seven genes related to Cd detoxification, including genes encoding peroxidase, chalcone synthase, and naringenin 3-dioxygenase, were upregulated in the Cd+M2 treatment. Strain M2 enhanced the Cd resistance and detoxification activity of wheat roots through the regulation of flavonoid biosynthesis and antioxidant enzyme activity. Moreover, strain M2 regulated the expression of genes related to phenylalanine metabolism and the MAPK signaling pathway to enhance Cd immobilization in roots. These results provide a theoretical basis for the use of phosphorus-solubilizing bacteria to remediate Cd-contaminated fields and reduce Cd uptake in wheat. [ABSTRACT FROM AUTHOR]

Seed shattering is an adaptive feature of seed dispersal in wild rice, and it is also an important agronomic trait affecting yield. Reduced seed shattering was a significant progress during rice domestication. However, the evolutionary pathway and molecular mechanism of hybrid seed shattering remain largely unknown. In order to gain a deeper understanding of the regulation of hybrid seed shattering, HS4, a locus conferring hybrid seed shattering between Oryza sativa and Oryza glaberrima, was identified and fine mapped to a 13.5-kb genomic region containing two putative genes during the development of chromosomal segment substitution lines (CSSLs). Expression analysis indicated that the hybrid seed shattering was not related to the expression of HS4. Preliminary research on the molecular mechanism of HS4-mediated hybrid seed shattering indicated that HS4HJX74 and HS4HP61 may form a multimer in heterozygotes, achieving the original function of a trihelix transcription factor through protein interaction. The identification and characterization of HS4 in this study not only provides new insights into the molecular mechanisms underlying hybrid seed shattering, but also provides a potential target for genome editing to reduce the difficulty of hybridization between the two species, facilitating hybrid breeding and increasing yield in rice. [ABSTRACT FROM AUTHOR]

Signal peptide peptidase (SPP) and its homologs, signal peptide peptidase-like (SPPL) proteases, are members of the GxGD-type aspartyl protease family, which is widespread in plants and animals and is a class of transmembrane proteins with significant biological functions. SPP/SPPLs have been identified; however, the functions of SPP/SPPL in rapeseed (Brassica napus L.) have not been reported. In this study, 26 SPP/SPPLs were identified in rapeseed and categorized into three groups: SPP, SPPL2, and SPPL3. These members mainly contained the Peptidase_A22 and PA domains, which were distributed on 17 out of 19 chromosomes. Evolutionary analyses indicated that BnaSPP/SPPLs evolved with a large number of whole-genome duplication (WGD) events and strong purifying selection. Members are widely expressed and play a key role in the growth and development of rapeseed. The regulation of rapeseed pollen fertility by the BnaSPPL4 gene was further validated through experiments based on bioinformatics analysis, concluding that BnaSPPL4 silencing causes male sterility. Cytological observation showed that male infertility caused by loss of BnaSPPL4 gene function occurs late in the mononucleate stage due to microspore dysplasia. [ABSTRACT FROM AUTHOR]

Most existing methods aiming to solve the fault identification problem of metal oxide arresters (MOAs) are limited by strong subjectivity in judgment, the significant impact of environmental temperature and humidity on the online monitoring of the resistance current, and poor generalization ability. Therefore, in this article, we propose an MOA fault identification method that combines suppressing environmental temperature and humidity interference with a stacked autoencoder (SAE). Firstly, a functional relationship model between resistance current and environmental temperature and humidity is established. Then, a temperature and humidity interference suppression method based on weighted nonlinear surface modeling is proposed to normalize the resistance current to the same reference temperature and humidity conditions. Finally, an MOA fault identification method combining the suppression of environmental temperature and humidity interference with an SAE is proposed. Furthermore, a comprehensive comparison is conducted on the recall, accuracy, F1-score, and average accuracy of support vector machine, random forest, logistic regression, and SAE classification algorithms in three different scenarios to demonstrate the effectiveness of the proposed method. The results indicate that environmental temperature and humidity interference suppression for resistive current prior to MOA fault classification significantly reduce the number of false alarms. Compared with other methods, the MOA fault identification method, which combines environmental temperature and humidity interference suppression with an SAE, has the highest average accuracy of 99.7%. [ABSTRACT FROM AUTHOR]

Hsp40s or DnaJ/J-proteins are evolutionarily conserved in all organisms as co-chaperones of molecular chaperone HSP70s that mainly participate in maintaining cellular protein homeostasis, such as protein folding, assembly, stabilization, and translocation under normal conditions as well as refolding and degradation under environmental stresses. It has been reported that Arabidopsis J-proteins are classified into four classes (types A-D) according to domain organization, but their phylogenetic relationships are unknown. Here, we identified 129 J-proteins in the world-wide popular vegetable Brassica oleracea, a close relative of the model plant Arabidopsis, and also revised the information of Arabidopsis J-proteins based on the latest online bioresources. According to phylogenetic analysis with domain organization and gene structure as references, the J-proteins from Arabidopsis and B. oleracea were classified into 15 main clades (I-XV) separated by a number of undefined small branches with remote relationship. Based on the number of members, they respectively belong to multigene clades, oligo-gene clades, and mono-gene clades. The J-protein genes from different clades may function together or separately to constitute a complicated regulatory network. This study provides a constructive viewpoint for J-protein classification and an informative platform for further functional dissection and resistant genes discovery related to genetic improvement of crop plants. Key words: J-proteins, Arabidopsis, Brassica oleracea, phylogenetic analysis, domain organization, gene structure. Resume : Les proteines HSP40s ou DNAJ/J ont ete conservees au cours de l'evolution chez tous les organismes a titre de co-chaperone des chaperones moleculaires HSP70s qui participent principalement au maintien de l'homeostasie proteique cellulaire, tel que le repliement, l'assemblage, la stabilisation et la translocation des proteines sous des conditions normales de meme que dans le repliement et la degradation en conditions de stress environnementaux. Il a ete rapporte que les proteines J chez l'Arabidopsis formaient quatre classes (types A-D) selon l'organisation des domaines, mais leurs relations phylogenetiques demeurent inconnues. Dans ce travail, les auteurs ont identifie 129 proteines J au sein du Brassica oleracea, une espece potagere mondialement apprecieeetunproche parent de l'espece modele Arabidopsis. Les auteurs ont egalement revise l'information sur les proteines J de l'Arabidopsis a l'aide des plus recentes ressources disponibles en ligne. Sur la base de l'analyse phylogenetique fondee sur l'organisation des domaines et la structure genique, les proteines J chez ces deux especes ont ete classifiees au sein de 15 clades principaux (I-XV), lesquels etaient separes par quelques petites branches mal definies aux relations eloignees. En fonction du nombre de membres, ces genes appartiennent a des clades multi-, oligo- ou monogeniques. Les proteines J des differents clades fonctionnent possiblement ensemble ou separement pour constituer un reseau de regulation complexe. Cette etude a fourni une assise constructive pour la classification et une plateforme informative pour de plus amples etudes fonctionnelles sur les proteines J ainsi que pour l'identification de genes de resistance lies a l'amelioration genetique des plantes cultivees. [Traduit par la Redaction] Mots-cles : proteines J, Arabidopsis, Brassica oleracea, analyse phylogenetique, organisation des domaines, structure genique., Introduction Prokaryotic and eukaryotic organisms respond and adapt to abiotic stress via the accumulation of heat shock proteins (HSPs) asa defense mechanism. HSPs are divided into seven groups based on [...]