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Neural network models, such as BP, LSTM, etc., support only numerical inputs, so data preprocessing needs to be carried out on the categorical variables to convert them into numerical data. For unordered multi-categorical variables, existing encoding methods may produce dimensional catastrophes and may also introduce additional order misrepresentation and distance bias in neural network computation. To solve the above problems, this paper proposes an unordered multi-categorical variable encoding method O-AE using orthogonal matrix for encoding and encoding representation learning and dimensionality reduction via an autoencoder. Bayesian optimization is used for hyperparameter optimization of the autoencoder. Finally, seven experiments were designed with the basic O-AE, Bayesian optimization of the hyperparameters of the autoencoder for O-AE, and other encoding methods to encode unordered multi-categorical variables in five datasets, and they were input into a BP neural network to carry out target prediction experiments. The results show that the experiments using O-AE and O-AE-b have better prediction results, proving that the method proposed in this paper is highly feasible and applicable and can be an optional method for the data processing of unordered multi-categorical variables. [ABSTRACT FROM AUTHOR]

Taking the vertical rolling roller and its double row tapered roller supporting bearing as the research object, a mechanical model for calculating the supporting force of bearing is constructed through mechanical analysis. By analyzing the contact force and local deformation of bearing roller, a calculation method for load distribution and fatigue life of bearing under composite load is established. Taking a specific supporting bearing of the vertical rolling mill as an example, the displacement curves of the bearing axis and the force on the rolling element are systematically discussed. On this basis, coupled calculations are conducted on the deformation of steel slab and the contact force of bearing during vertical rolling process, and the influences of several process parameters on roller stress and bearing life are studied. The research shows that the axis trajectory of the bearing is an irregular ellipse. The contact force between the roller and the inner ring rib of the bearing is very small. The maximum contact stress between the roller and the inner ring is slightly greater than that of roller-outer ring. When the width reduction rate, slab thickness, slab width and vertical roller radius increase, the maximum contact stress of the roller increases, and the fatigue life of the bearing decreases. Among the main rolling parameters, the influence of width reduction rate and slab thickness is more significant. The difference of load value between the two rows increases with the increase of the composite load, which results in the decrease of bearing life. [ABSTRACT FROM AUTHOR]

Histone lactylation is a metabolic stress‐related histone modification. However, the role of histone lactylation in the development of sepsis‐associated acute kidney injury (SA‐AKI) remains unclear. Here, histone H3K18 lactylation (H3K18la) is elevated in SA‐AKI, which is reported in this study. Furthermore, this lactate‐dependent histone modification is enriched at the promoter of Ras homolog gene family member A (RhoA) and positively correlated with the transcription. Correction of abnormal lactate levels resulted in a reversal of abnormal histone lactylation at the promoter of RhoA. Examination of related mechanism revealed that histone lactylation promoted the RhoA/Rho‐associated protein kinase (ROCK) /Ezrin signaling, the activation of nuclear factor‐κB (NF‐κB), inflammation, cell apoptosis, and aggravated renal dysfunction. In addition, Ezrin can undergo lactylation modification. Multiple lactylation sites are identified in Ezrin and confirmed that lactylation mainly occurred at the K263 site. The role of histone lactylation is revealed in SA‐AKI and reportes a novel post‐translational modification in Ezrin. Its potential role in regulating inflammatory metabolic adaptation of renal proximal tubule epithelial cells is also elucidated. The results provide novel insights into the epigenetic regulation of the onset of SA‐AKI. [ABSTRACT FROM AUTHOR]

Prefabricated cabin modular units (PMCUs) are a widespread type of intermediate products used during ship or offshore platform construction. This paper focuses on the scheduling problem of PMCU assembly flow shops, which is summarized as a multi-objective, fuzzy-blocking hybrid flow-shop-scheduling problem based on learning and fatigue effects (FB-HFSP-LF) to minimize the maximum fuzzy makespan and maximize the average fuzzy due-date agreement index. This paper proposes a multi-objective non-dominated sorting gravitational search algorithm (MONSGSA) to solve it. In the proposed MONSGSA, the ranked-order value is used to convert continuous solutions to discrete solutions. Multi-dimensional Latin hypercube sampling is used to enhance initial population diversity. Setting up an external archive to maintain non-dominated solutions while introducing an adaptive inertia factor and a trap avoidance operator to guide individual positional updates. The results of multiple sets of experiments show that Pareto solutions of MONSGSA have better distribution and convergence compared to other competitors. Finally, the instance of PMCU manufacturer is used for validation, and the results show that MONSGSA has better applicability to practical problems. [ABSTRACT FROM AUTHOR]

Gas foil bearings are particularly suitable for supporting rotors of hydrogen fuel cell air compressors. Based on Reynolds equation and elastic mechanics theory, a fluid-structure interaction model of gas foil bearings is introduced. A series of perturbation equations are developed and solved to obtain stiffness and damping coefficients of the foil bearings at different rotational speeds. A lumped model of the bearing-rotor system is developed and the rotor stability is analysed by innovatively applying Riccati transfer matrix method. The natural frequencies of the rotor are calculated and then the Campbell diagram is plotted. Subsequently, the critical speeds and the corresponding vibration modes are obtained. The predicted values of the proposed model are highly consistent with the reported experimental results and finite element results, indicating the accuracy of the model. Based on the calculation of rotor unbalance response, further investigation on the effects of unbalance parameters on unbalance response is conducted. The results obtained in this paper could provide theoretical reference for the design of foil bearing supported rotors. [ABSTRACT FROM AUTHOR]

To evaluate the analytical characteristics of a novel high-sensitivity cardiac troponin T (hs-cTnT) test on the automatic light-initiated chemiluminescent assay (LiCA®) system, and validated its diagnostic performance for non-ST-segment elevation myocardial infarction (NSTEMI). Studies included an extensive analytical evaluation and established the 99th percentile upper reference limit (URL) from apparently healthy individuals, followed by a diagnostic performance validation for NSTEMI. Sex-specific 99th percentile URLs were 16.0 ng/L (1.7 % CV: coefficient of variation) for men (21–92 years) and 13.4 ng/L (2.0 % CV) for women (23–87 years) in serum, and 30.6 ng/L (0.9 % CV) for men (18–87 years) and 20.2 ng/L (1.4 % CV) for women (18–88 years) in heparin plasma. Detection rates in healthy individuals ranged from 98.9 to 100 %. An excellent agreement was identified between LiCA® and Elecsys® assays with a correlation coefficient of 0.993 and mean bias of −0.7 % (−1.8–0.4 %) across the full measuring range, while the correlation coefficient and overall bias were 0.967 and −1.1 % (−2.5–0.3 %) for the lower levels of cTnT (10–100 ng/L), respectively. At the specific medical decision levels (14.0 and 52.0 ng/L), assay difference was estimated to be <5.0 %. No significant difference was found between these two assays in terms of area under curve (AUC), sensitivity and specificity, negative predictive value (NPV) and positive predictive value (PPV) for the diagnosis of NSTEMI. LiCA® hs-cTnT is a reliable 3rd-generation (level 4) high-sensitivity assay for detecting cardiac troponin T. The assay is acceptable for practical use in the diagnosis of NSTEMI. [ABSTRACT FROM AUTHOR]

In the era of Industry 4.0 to 5.0, the manufacturing industry is dedicated to improving its production efficiency, control capability and competitiveness with intelligent enhancement. As a typical discrete manufacturing industry, it is difficult for ocean engineering (OE) manufacturers to accurately control the entire production process, and the establishment of an integrated system supported by digital twin (DT) technology is a better solution. This paper proposes a comprehensive set of system architectures for the DT workshop. It focuses on planning, which is the main line of control, to establish a model based on graph neural networks (GNNs) and suggests five decision-support approaches associated with the model from a practical application perspective. The utilization of complete twin data for prediction and visual simulation effectively eliminates the problem of unexpected factors interfering with scheduling in enterprise production planning and achieves the goals of rapid processing and just-in-time completion. The planning model is based on the attention mechanism, which characterizes the disjunctive graph, extracts the input GNN, and outputs the scheduling decision by constructing the multi-attention network of operations and machines to deal with the complicated "operation–machine" combination relationship. The proposed method has been verified in the case of structural assembly and welding workshops, has validity and reliability, and is superior to the traditional priority scheduling rules and heuristics in terms of precision rate and rapidity. Furthermore, the DT system completes the production line application, and its proven reliability supports its full-scale application in future smart factories. [ABSTRACT FROM AUTHOR]

Taking the high-speed pin insertion machine as the research object, the mechanical analysis of its pin insertion mechanism was carried out, the cylindrical cam groove surface equation was established. The contact mechanics model of the cylindrical cam roller and the groove, and the geometric model of the roller rolling in the groove were established. Based on Hertz contact theory, the maximum contact stress of the contact point between roller and groove was calculated at each moment in the course of the cam rotation. Based on the Miner linear fatigue cumulative damage theory, the dangerous point in the circumferential direction of the roller was judged, and the dangerous point was taken as the object to realize the quantitative calculation of the fatigue life of the roller. Through a specific example, the influence of roller diameter, cam diameter, contact length, and cam rotation speed on the contact fatigue life of the cam roller was illustrated. The calculation results showed that: when the diameter of the cam roller increased from 10 mm to 26 mm, the fatigue life increased by 14.1 times; when the diameter of the cam increased from 50 mm to 140 mm, the fatigue life increased by 7.5 times; when the contact length increased from 5 mm to 15 mm, the fatigue life of the cam roller increased by 26.0 times; when the cam speed increased from 600 r⋅min-1 to 1 300 r⋅min-1, the fatigue life decreased to 0.449% of the original. [ABSTRACT FROM AUTHOR]

Taking bump-type gas foil bearings as the research object, a deformation model of bump foil and a thin-plate finite element model of top foil were proposed. By solving Reynolds equation and energy equation, the pressure distribution and the temperature distribution of gas films in foil bearings were obtained. Further, a numerical method for calculating the lubrication performance of gas foil bearings with considering the surface roughness was proposed. With a specific example, effects of the surface roughness on the bearing lubrication performance were parametrically studied. The results indicate that rougher journal surface can lead to larger fluctuation of the lubrication performance, while surface roughness of top foil has few effects on the fluctuation. Moreover, the mean values of performance parameters almost remain constant at different values of surface roughness. [ABSTRACT FROM AUTHOR]

Obstetric antiphospholipid syndrome (OAPS) is an autoimmune disorder with severe life-threatening complications shown during pregnancy. It has been reported that the increase in CD16+CD56dim natural killer (NK) cells in peripheral blood are risk factors for recurrent miscarriages, but this expression of CD16+CD56dim NK cells in OAPS patients has not been reported, and the mechanism is not clearly illustrated. In this study, we compared the distributional profiles of different NK cell subsets and the expressions of NK cell-activating receptors in peripheral blood of patients with OAPS and healthy women. Our results showed significantly increased NKG2A−NKG2D+ subset and decreased NKG2A+NKG2D− subset in CD3− CD16+CD56dim NK cells, CD3−CD16−CD56bright NK cells and CD56+T cells in OAPS patients compared with those in healthy control women. The CD27−CD11b+ subset significantly increased in CD3−CD16+CD56dim NK cells in OAPS patients compared with those in healthy control women. In addition, the NKG2A−NKG2D+ subset in CD3−CD16+CD56dim NK subset in triple positivity was higher than single positivity OAPS patients. At the optimal diagnostic threshold established by ROC analysis, using the cut-off of NKG2A−NKG2D+ and CD27−CD11b+ subset in CD3−CD16+CD56dim NK cells is 10.10% and 92.75%, the sensitivity of NKG2A−NKG2D+ and CD27−CD11b+ to detect patients with OAPS compared with healthy control results was 94.1% and 60.8%, and specificity was 84.2% and 89.5%, respectively, with an area under the curve (AUC) of 0.903 and 0.829, respectively. The NKG2A−NKG2D+ subset in CD3−CD16+CD56dim NK cells was positively correlated with the antiphospholipid antibodies lg anti-aCL IgG, lg anti-aCL IgM, lg anti-aCL IgA, lg anti-β2GP1 IgM and Complement 4(C4), while the CD27+CD11b+ subset in CD3−CD16+CD56dim NK cells was correlated with lg anti-β2GP1 IgG and lg anti-β2GP1 IgA. These results suggested that the NK cytotoxic function enhanced in OAPS patients and unbalanced of NK activating receptors and inhibiting receptors may contribute to the immune pathogenesis of OAPS. [ABSTRACT FROM AUTHOR]