Dataset Information

The Effect of Friction on Actuation Torques of Foldable Rollover Protective Structures.

ABSTRACT: The number of fatal tractor rollover accidents with an inoperative foldable rollover protective structure (FROPS) has increased sharply in recent years. Operators frequently leave the FROPS in the folded-down position after lowering the FROPS to pass a low overhead obstacle. One possible explanation for leaving the FROPS in the folded position is that raising and lowering the FROPS is a time-consuming and strenuous process. The actuation torques required to raise and lower a FROPS are not well known and may be influenced by friction. The actuation torques of ten FROPS from four different models were measured. One model FROPS was tested on seven different vehicles, and three models were tested separately. The dynamic and static (initiation and holding) actuation torques were measured to evaluate the effect of static and kinetic friction on actuation torque. The dynamic actuation torques were measured before and after greasing the FROPS. The proposed instruction to measure the actuation torque based on OECD Code 7 was evaluated. Results showed that friction has a significant effect on the measured actuation torque and can increase the actuation torque by up to 212%. The friction varies between FROPS of the same model, which is due to variations in the manufacturing, maintenance, and age of the FROPS. The friction force could be decreased by greasing the FROPS, and decreasing the friction increased the lowering resisting torques and decreased raising torques of FROPS. The measured actuation torque based on OECD Code 7 instruction (static holding) is not a constant value. The dynamic method is recommended for measuring FROPS actuation torques.

SUBMITTER: Khorsandi F

PROVIDER: S-EPMC7384238 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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The Effect of Friction on Actuation Torques of Foldable Rollover Protective Structures.

Khorsandi Farzaneh F Ayers Paul D PD

Journal of agricultural safety and health 20180101 4

The number of fatal tractor rollover accidents with an inoperative foldable rollover protective structure (FROPS) has increased sharply in recent years. Operators frequently leave the FROPS in the folded-down position after lowering the FROPS to pass a low overhead obstacle. One possible explanation for leaving the FROPS in the folded position is that raising and lowering the FROPS is a time-consuming and strenuous process. The actuation torques required to raise and lower a FROPS are not well k ...[more]

PMID: 32719578

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Project description:BackgroundTertiary lymphoid structures (TLS) have an effect on hepatocellular carcinoma (HCC), but the underlying mechanism remains to be elucidated.MethodsIntratumoral TLS (iTLS) was classified in the Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC) cohort using pathological sections from the Cancer Digital Slide Archive. Univariate and multivariate Cox regression analyses were performed to validate the effect of iTLS on overall survival (OS), relapse-free survival (RFS), and disease-free survival (DFS). The genes differentially expressed between the iTLS-negative and iTLS-positive groups were analyzed in combination with sequencing data. Gene set enrichment analysis (GSEA) was used to explore the signaling pathways affected by these differentially expressed genes. The random forest algorithm was used to identify genes with the highest correlation with the iTLS in the training set. Multivariate logistic regression was used to build a model to predict iTLS in tissue samples. Spearman's correlation was used to analyze the relationship between TLS-associated chemokines and signature genes, and CIBERSORT was used to calculate immune infiltration scores. Copy number variation and its relationship with immune cell infiltration and signature genes were assessed using the gene set cancer analysis (GSCA). The Correlation R package was used for gene ontology (GO), disease ontology (DO), and gene mutation analyses. The GSCA was used for drug sensitivity analysis. LASSO regression was used to build prognostic models, and external data were used to validate the models.ResultsThere were 218 positive and 146 negative samples for iTLS. iTLS was significantly associated with better RFS and DFS according to Cox regression analysis. Twenty signature genes that were highly associated with iTLS positivity were identified. GO and mutation analyses revealed that the signature genes were associated with immunity. Most signature genes were sensitive to immune checkpoint inhibitors. Risk scores calculated using a characteristic gene-based prognostic model were found to be an independent prognostic factor for OS.ConclusionsThe improvement of RFS in HCC by iTLS was not limited to the early period as previously reported. iTLS improved DFS in patients. Characteristic genes are closely related to the formation of iTLS and TLS chemokines in HCC. These genes are closely related to immunity in terms of cellular infiltration, biological functions, and signaling pathways. Most are sensitive to immune checkpoint inhibitors, and their expression levels can affect prognosis.

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Dataset Information

The Effect of Friction on Actuation Torques of Foldable Rollover Protective Structures.

Publications

The Effect of Friction on Actuation Torques of Foldable Rollover Protective Structures.

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