133 research outputs found

    Vibration signal analysis of main coolant pump flywheel based on Hilbert–Huang transform

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    AbstractIn this paper, a three-dimensional model for the dynamic analysis of a flywheel based on the finite element method is presented.The static structure analysis for the model provides stress and strain distribution cloud charts. The modal analysis provides the basis of dynamic analysis due to its ability to obtain the natural frequencies and the vibration–made vectors of the first 10 orders.The results show the main faults are attrition and cracks, while also indicating the locations and patterns of faults. The harmonic response simulation was performed to gain the vibration response of the flywheel under operation.In this paper, we present a Hilbert–Huang transform (HHT) algorithm for flywheel vibration analysis. The simulation indicated that the proposed flywheel vibration signal analysis method performs well, which means that the method can lay the foundation for the detection and diagnosis in a reactor main coolant pump

    Overexpression of OsFTL10 induces early flowering and improves drought tolerance in Oryza sativa L.

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    Flowering time control is critically important for the reproductive accomplishment of higher plants as floral transition can be affected by both environmental and endogenous signals. Flowering Locus T-like (FTL) genes are major genetic determinants of flowering in plants. In rice, 13 OsFTL genes have been annotated in the genome and amongst them, Hd3a (OsFTL2) and RFT1 (OsFTL3) have been studied extensively and their functions are confirmed as central florigens that control rice flowering under short day and long day environment, respectively. In this report, a rice OsFTL gene, OsFTL10, was characterized, and its function on flowering and abiotic stress was investigated. The expression level of OsFTL10 was high in young seedlings and shown to be induced by GA3 and drought stress. Overexpression of OsFTL10 resulted in earlier flowering in rice plants by up to 2 weeks, through up-regulation of the downstream gene OsMADS15. OsFTL10 also regulated Ehd1 and OsMADS51 through a feedback mechanism. The OsFTL10 protein was also detected in both nucleus and cytoplasm. Furthermore, yeast two hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) results show that OsFTL10 could interact with multiple 14-3-3s, suggesting that OsFTL10 might function in a similar way to Hd3a in promoting rice flowering by forming a FAC complex with 14-3-3, and OsFD1. Further experiments revealed that constitutive expression of OsFTL10 improved the drought tolerance of transgenic plants by stimulating the expression of drought responsive genes. These results suggest that rice FTL genes might function in flowering promotion and responses to environmental signals

    Childhood psychological abuse and relational aggression among adolescents: A moderated chain mediation model

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    IntroductionAdolescents are in a period when a marked upward trend of adolescents relational aggression. Even though previous studies have found that childhood psychological abuse experience is an important factor influencing adolescent relational aggression, it is unclear when and under what circumstances childhood psychological abuse impacts adolescent relational aggression. This study constructed a moderated chain mediation model to investigate the influence of childhood psychological abuse on relational aggression among Chinese adolescents and its internal mechanism.MethodsData from 1868 (923 male and 945 female, M = 14.31, SD = 1.60) Chinese adolescents in two full-time middle schools in Guangzhou were collected via a cross-sectional survey in 2020. Adolescents reported on childhood psychological abuse, relational aggression, rejection sensitivity relational victimization and cognitive reappraisal.ResultsThe results demonstrated that: (1) childhood psychological abuse was significantly positively related to relational aggression; (2) childhood psychological abuse was significantly linked with adolescents’ relational aggression through the separate mediating effects of rejection sensitivity and relational victimization, as well as through the chain mediating effects of rejection sensitivity and relational victimization; (3) the chain mediated effect of childhood psychological abuse on relational aggression through rejection sensitivity and relational victimization was moderated by cognitive reappraisal.ConclusionThese findings indicate that childhood psychological abuse, as a kind of poor parenting style, has influence on adolescents’ internal personality (rejection sensitivity) and external behavior development (relational victimization and relational aggression). This study is helpful to demonstrate the protective effect of cognitive reappraisal and reveal the internal mechanism of childhood psychological abuse on relational aggression

    Open-source genomic analysis of Shiga-toxin–producing E. coli O104:H4

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    An outbreak caused by Shiga-toxin–producing Escherichia coli O104:H4 occurred in Germany in May and June of 2011, with more than 3000 persons infected. Here, we report a cluster of cases associated with a single family and describe an open-source genomic analysis of an isolate from one member of the family. This analysis involved the use of rapid, bench-top DNA sequencing technology, open-source data release, and prompt crowd-sourced analyses. In less than a week, these studies revealed that the outbreak strain belonged to an enteroaggregative E. coli lineage that had acquired genes for Shiga toxin 2 and for antibiotic resistance

    Correlation and predictive ability of sensory characteristics and social interaction in children with autism spectrum disorder

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    BackgroundIndividuals with autism spectrum disorder (ASD) often have different social characteristics and particular sensory processing patterns, and these sensory behaviors may affect their social functioning. The objective of our study is to investigate the sensory profiles of children with ASD and their association with social behavior. Specifically, we aim to identify the predictive role of sensory processing in social functioning.MethodsThe Short Sensory Profile (SSP) was utilized to analyze sensory differences between ASD children and their peers. The Social Responsiveness Scale (SRS) and other clinical scales were employed to assess the social functioning of children with ASD. Additionally, the predictive ability of sensory perception on social performance was discussed using random forest and support vector machine (SVM) models.ResultsThe SSP scores of ASD children were lower than those of the control group, and there was a significant negative correlation between SSP scores and clinical scale scores (P < 0.05). The random forest and SVM models, using all the features, showed higher sensitivity, while the random forest model with 7-feature factors had the highest specificity. The area under the receiver operating characteristic (ROC) curve (AUC) for all the models was higher than 0.8.ConclusionAutistic children in our study have different patterns of sensory processing than their peers, which are significantly related to their patterns of social functioning. Sensory features can serve as a good predictor of social functioning in individuals with ASD

    IKKα contributes to UVB-induced VEGF expression by regulating AP-1 transactivation

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    Exposure to ultraviolet B (UVB) irradiation from sunlight induces the upregulation of VEGF, a potent angiogenic factor that is critical for mediating angiogenesis-associated photodamage. However, the molecular mechanisms related to UVB-induced VEGF expression have not been fully defined. Here, we demonstrate that one of the catalytic subunits of the IκB kinase complex (IKK), IKKα, plays a critical role in mediating UVB-induced VEGF expression in mouse embryonic fibroblasts (MEFs), which requires IKKα kinase activity but is independent of IKKβ, IKKγ and the transactivation of NF-κB. We further show that the transcriptional factor AP-1 functions as the downstream target of IKKα that is responsible for VEGF induction under UVB exposure. Both the accumulation of AP-1 component, c-Fos and the transactivation of AP-1 by UVB require the activated IKKα located within the nucleus. Moreover, nuclear IKKα can associate with c-Fos and recruit to the vegf promoter regions containing AP-1-responsive element and then trigger phosphorylation of the promoter-bound histone H3. Thus, our results have revealed a novel independent role for IKKα in controlling VEGF expression during the cellular UVB response by regulating the induction of the AP-1 component and phosphorylating histone H3 to facilitate AP-1 transactivation. Targeting IKKα shows promise for the prevention of UVB-induced angiogenesis and the associated photodamage

    Fine root decomposition in forest ecosystems: an ecological perspective

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    Fine root decomposition is a physio-biochemical activity that is critical to the global carbon cycle (C) in forest ecosystems. It is crucial to investigate the mechanisms and factors that control fine root decomposition in forest ecosystems to understand their system-level carbon balance. This process can be influenced by several abiotic (e.g., mean annual temperature, mean annual precipitation, site elevation, stand age, salinity, soil pH) and biotic (e.g., microorganism, substrate quality) variables. Comparing decomposition rates within sites reveals positive impacts of nitrogen and phosphorus concentrations and negative effects of lignin concentration. Nevertheless, estimating the actual fine root breakdown is difficult due to inadequate methods, anthropogenic activities, and the impact of climate change. Herein, we propose that how fine root substrate and soil physiochemical characteristics interact with soil microorganisms to influence fine root decomposition. This review summarized the elements that influence this process, as well as the research methods used to investigate it. There is also need to study the influence of annual and seasonal changes affecting fine root decomposition. This cumulative evidence will provide information on temporal and spatial dynamics of forest ecosystems, and will determine how logging and reforestation affect fine root decomposition

    Global Analysis of Gene Expression Profiles in Developing Physic Nut (Jatropha curcas L.) Seeds

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    Background: Physic nut (Jatropha curcas L.) is an oilseed plant species with high potential utility as a biofuel. Furthermore, following recent sequencing of its genome and the availability of expressed sequence tag (EST) libraries, it is a valuable model plant for studying carbon assimilation in endosperms of oilseed plants. There have been several transcriptomic analyses of developing physic nut seeds using ESTs, but they have provided limited information on the accumulation of stored resources in the seeds. Methodology/Principal Findings: We applied next-generation Illumina sequencing technology to analyze global gen
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