Effect of Surface Roughness on Elastohydrodynamic Lubrication Performance of Cylindrical Roller Bearing

In order to study the effect of surface roughness on the Elastohydrodynamic Lubrication (EHL) performance of cylindrical roller bearing, an EHL model of cylindrical roller bearing with three dimensional surface cosine roughness based on finite length line contact theory is established. The EHL performance of cylindrical roller bearing is calculated by the Finite Difference Method (FDM) program, with which the effects of surface cosine roughness amplitude, wavelength and texture angle on EHL performance of cylindrical roller bearing are analyzed. The numerical results show that the roughness amplitude, wavelength and texture angle have great influence on the EHL performance in the contact area. The increase of roughness amplitude and wavelength in a reasonable range is beneficial to the enhancement of EHL performance of the cylindrical roller bearing, and the transverse roughness is more favorable to enhance the bearing capacity and reduce the friction coefficient

Dimethyl 3,3′-diphenyl-2,2′-[(S)-thio­phene-2,5-diylbis(carbonyl­aza­nedi­yl)]dipropano­ate tetra­hydro­furan monosolvate

The title compound, C26H26N2O6S·C4H8O, a solvated bis-amide derivative, is also a chiral amino acid ester with l-phenyl­alanine methyl ester groups as amine substituents. The thio­phene-2,5-dicarboxamide core approximates C 2 point symmetry. The tetra­hydro­furan solvent mol­ecule is linked to the main mol­ecule through an inter­molecular N—H⋯O hydrogen bond. The central ring makes dihedral angles of 90.0 (2) and 76.5 (2)° with the pendant rings

Eco-Stoichiometric Alterations in Paddy Soil Ecosystem Driven by Phosphorus Application

Agricultural fertilization may change processes of elemental biogeochemical cycles and alter the ecological function. Ecoenzymatic stoichiometric feature plays a critical role in global soil carbon (C) metabolism, driving element cycles, and mediating atmospheric composition in response to agricultural nutrient management. Despite the importance on crop growth, the role of phosphorous (P) in compliance with eco-stoichiometry on soil C and nitrogen (N) sequestration in the paddy field remains poorly understood in the context of climate change. Here, we collected soil samples from a field experiment after 6 years of chemical P application at a gradient of 0 (P-0), 30 (P-30), 60 (P-60), and 90 (P-90) kg ha⁻¹ in order to evaluate the role of P on stoichiometric properties in terms of soil chemical, microbial biomass, and eco-enzyme activities as well as greenhouse gas (GHG: CO₂, N₂O and CH₄) emissions. Continuous P input increased soil total organic C and N by 1.3–9.2% and 3%–13%, respectively. P input induced C and N limitations as indicated by the decreased ratio of C:P and N:P in the soil and microbial biomass. A synergistic mechanism among the ecoenzymatic stoichiometry, which regulated the ecological function of microbial C and N acquisition and were stoichiometrically related to P input, stimulated soil C and N sequestration in the paddy field. The lower emissions of N₂O and CH₄ under the higher P application (P-60 and P-90) in July and the insignificant difference in N₂O emission in August compared to P-30; however, continuous P input enhanced CO₂ fluxes for both samplings. There is a technical conflict for simultaneously regulating three types of GHGs in terms of the eco-stoichiometry mechanism under P fertilization. Thus, it is recommended that the P input in paddy fields not exceed 60 kg ha⁻¹ may maximize soil C sequestration, minimize P export, and guarantee grain yields

Attenuation of kainic acid-induced epilepsy by butyrate is associated with inhibition of glial activation

Purpose: To investigate the function and potential therapeutic relevance of butyrate in epilepsy using rat models of kainic acid (KA)-induced epilepsy.Methods: The neurotoxin KA was applied to rats and rat astrocytes to establish models of epilepsy in vivo and in vitro. Multiple parameters, including behavioural seizure scores, were evaluated in rats and rat astrocytes treated with KA alone or in combination with butyrate. Western blot was performed to examine the levels of phosphorylated extracellular signal-related kinase (p-ERK), proinflammatory cytokine (IL-1ß), and glial fibrillary acidic protein (GFAP).Results: Significant increases were observed in the seizure-related proteins p-ERK and GFAP and in the proinflammatory cytokine IL-1ß in KA-treated rats and rat astrocytes (p < 0.05). Butyrate treatment attenuated KA-induced epileptic behaviour in rats and significantly reduced the expression of p-ERK, GFAP, and IL-1ß in a dose-dependent manner (p < 0.05).Conclusion: Butyrate has potential as a treatment for epilepsy by inhibiting the activation of p-ERK, astrogliosis, and inflammation, which were induced by KA in rats and rat astrocytes.Keywords: Kainic acid, Epilepsy, Butyrate, Glial activation, Astrogliosi

Iterative Nearest Neighborhood Oversampling in Semisupervised Learning from Imbalanced Data

Transductive graph-based semi-supervised learning methods usually build an undirected graph utilizing both labeled and unlabeled samples as vertices. Those methods propagate label information of labeled samples to neighbors through their edges in order to get the predicted labels of unlabeled samples. Most popular semi-supervised learning approaches are sensitive to initial label distribution happened in imbalanced labeled datasets. The class boundary will be severely skewed by the majority classes in an imbalanced classification. In this paper, we proposed a simple and effective approach to alleviate the unfavorable influence of imbalance problem by iteratively selecting a few unlabeled samples and adding them into the minority classes to form a balanced labeled dataset for the learning methods afterwards. The experiments on UCI datasets and MNIST handwritten digits dataset showed that the proposed approach outperforms other existing state-of-art methods

(−)-Dimethyl 3,3′-diphenyl-2,2′-[pyridine-2,6-diylbis(carbonyl­imino)]dipropanoate

The title compound, C27H27N3O6, a bis-amide derivative, is also a chiral amino acid ester with l-phenyl­alanine methyl ester groups as amine substituents. The pyridine ring is oriented at dihedral angles of 89.69 (3) and 62.95 (3)° with respect to the phenyl rings, while the dihedral angle between the phenyl rings is 60.76 (3)°. In the crystal structure, inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains. One of the carbonyl O atoms and one of the meth­oxy CH3 groups are disordered over two positions. The O atom was refined with occupancies of 0.69 (13) and 0.31 (13), while C and H atoms were refined with occupancies of 0.69 (8) and 0.31 (8)