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Wheel‐rail adhesion is important to the traction and braking of railway vehicles. This paper develops a three‐dimensional numerical model considering surface roughness and temperature to investigate water‐contaminated adhesion characteristics. A simplified elastohydrodynamic lubrication model considering the thermal effect is developed to obtain the normal load carried by liquid film and asperities. Meanwhile, a third body layer (3BL) model, which considers the effects of pressure and temperature on 3BL, is used to calculate the tangential stress and friction coefficient of asperity contact. To verify the numerical model, firstly, the results are compared with the existing experimental results at low and high speeds. In addition, the effects of surface roughness and temperature on adhesion coefficient are investigated. Furthermore, the elastoplastic behaviour of the tangential stress and the adhesion characteristics for large creepages are studied. The obtained adhesion‐creepage curve can represent the decreasing trend after reaching saturation because of temperature. [ABSTRACT FROM AUTHOR]

In this work, we proposed an acid hydrolysis-based analytical method for the detection of Alternaria toxins (ATs) in solanaceous vegetables and their products with solid-phase extraction (SPE) and ultrahigh-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS). This study was the first to reveal that some compounds in the eggplant matrix bind to altenusin (ALS). Validation under optimal sample preparation conditions showed that the method met the EU criteria, exhibiting good linearity (R2 > 0.99), matrix effects (−66.6–−20.5%), satisfying recovery (72.0–107.4%), acceptable precision (1.5–15.5%), and satisfactory sensitivity (0.05–2 µg/kg for limit of detection, 2–5 µg/kg for limit of quantification). Out of 393 marketed samples, only 47 samples were detected, ranging from 0.54–806 μg/kg. Though the occurrence ratio (2.72%) in solanaceous vegetables could be negligible, the pollution status in solanaceous vegetable products was much more serious, and the incidences were 41.1%. In the 47 contaminated samples, the incidences were 4.26% for alternariol monomethyl ether (AME), 6.38% for alternariol (AOH) and altenuene (ALT), 42.6% for tentoxin (TEN), and 55.3% for tenuazonic acid (TeA). [ABSTRACT FROM AUTHOR]

Herein, nanoflower-shaped Mn-doped NiO nano-enzyme composites with high catalytic performance and excellent conductivity were grown on 3D flexible carbon fiber cloth (CFC) via hydrothermal and calcination methods to construct an efficient flexible glucose-sensitive detection electrode. For electrochemical-based sensors, high conductivity is a prerequisite for reliable data acquisition. To avoid the problems associated with using insulating Nafion or paraffin binders, we adopted a strategy of directly growing Mn-doped NiO onto the electrode surface, thereby avoiding interference due to the oxidization of species present in real samples at higher redox potentials, since Ni2+/Ni3+ has low redox potential. Therefore, the electrode has a linear range of 3–5166 μM for glucose detection, with a detection limit as low as 0.28 μM, showing excellent selectivity and reproducibility. The composite-modified electrode provides accurate detection results with real human serum samples, which are in full agreement with those of commercial blood glucose meters. In addition, we tested the glucose content in tea and sorghum fermentation broth at different stages, further expanding the application range of the Mn-NiO sensors. The nano-enzyme sensor fabricated herein offers a new idea for further integration into wearable flexible electronic devices for accurate glucose detection. [ABSTRACT FROM AUTHOR]

RAC/Rho of plant (ROP) GTPases are major molecular switches that control diverse signaling cascades for plant growth, development, and defense. Here, we discovered a signaling node that connects RAC/ROPs to cytokinins. Rice (Oryza sativa) plants develop a fibrous root system mainly composed of crown roots. Cytokinin signaling via a phosphorelay system is critical for crown root development. We show that OsRopGEF10, which activates RAC/ROPs, acts upstream of the cytoplasmic-nuclear shuttling phosphotransfer proteins AHPs of the cytokinin signaling pathway to promote crown root development. Mutations of OsRopGEF10 induced hypersensitivity to cytokinin, whereas overexpressing this gene reduced the cytokinin response. Loss of OsRopGEF10 function reduced the expression of the response regulator gene OsRR6, a repressor of cytokinin signaling, and impaired crown root development. Mutations in OsAHP1/2 led to increased crown root production and rescued the crown root defect of Osropgef10. Furthermore, auxin activates the ROP GTPase OsRAC3, which attenuates cytokinin signaling for crown root initiation. Molecular interactions between OsRopGEF10, OsRAC3, and OsAHP1/2 implicate a mechanism whereby OsRopGEF10-activated OsRAC3 recruits OsAHP1/2 to the cortical cytoplasm, sequestering them from their phosphorelay function in the nucleus. Together, our findings uncover the OsRopGEF10–OsRAC3–OsAHP1/2 signaling module, establish a link between RAC/ROPs and cytokinin, and reveal molecular crosstalk between auxin and cytokinin during crown root development. The OsRopGEF10-OsRAC3 module attenuates cytokinin signaling by sequestering AHP cytokinin signaling proteins to the cortical cytoplasm to promote crown root development in rice. [ABSTRACT FROM AUTHOR]

Few studies have focused on the link between active surveillance (AS) and Gleason score upgrade (GSU) and its impact on the prognosis of patients with prostate cancer (PCa). This study aimed to analyze the effect of AS duration on GSU and prognostic value based on risk stratification. All eligible patients were risk-stratified according to AUA guidelines into low-risk (LR), favorable intermediate-risk (FIR), and unfavorable intermediate-risk (UIR) PCa. Within the Surveillance, Epidemiology, and End Results Program (SEER) database, 28,368 LR, 27,243 FIR, and 12,210 UIR PCa patients were included. The relationship between AS duration and GSU was identified with univariate and multivariate logistic regression. Discrimination according to risk stratification of AS duration and GSU was tested by Kaplan–Meier analysis and competing risk regression models. The proportion of patients who chose AS was the highest among LR PCa (3434, 12.1%), while the proportion in UIR PCa was the lowest (887, 7.3%). The AS duration was only associated with GSU in LR PCa, with a high Gleason score (GS) at diagnosis being a strong predictor of GSU for FIR and UIR PCa. Kaplan–Meier analysis indicated that long-term surveillance only made a significant difference in prognosis in UIR PCa. The competing risk analysis indicated that once GS was upgraded to 8 or above, the prognosis in each group was significantly worse. AS is recommended for LR and FIR PCa until GS is upgraded to 8, but AS may not be suitable for some UIR PCa patients. [ABSTRACT FROM AUTHOR]

Aresenic trioxide (ATO) is proven to be active against leukaemia cells by inducing apoptosis and differentiation. Even though ATO could effectively induce remissions of leukaemia cells, the drug resistance was observed occasionally. To further dissect the mechanism of ATO resistance, we selected the ATO‐resistant SH‐SY5Y cells and found that Bcl‐2 controlled the sensitivity of ATO in SH‐SY5Y cells. We report that necroptosis, autophagy, NF‐ƘB and MAPK signalling pathway are not involved in ATO‐induced apoptosis. Moreover, the ATO‐resistant cells showed distinct mitochondrial morphology compared with that of ATO‐sensitive cells. Intriguingly, nude mice‐bearing ATO‐sensitive cells derived xenograft tumours are more sensitive to ATO treatment compared with that of ATO‐resistant cells. These data demonstrate that cancer cells can acquire the ATO‐resistance ability by increasing the Bcl‐2 expression. [ABSTRACT FROM AUTHOR]

All-polymer solar cells have made substantial achievements in recent years, offering numerous unsettled subjects for mechanical researchers. In order to quantitatively study the influence of the molecular electrostatic potential on the charge generation proposed by the experimenter, we simulate the ultrafast dynamics of the charge-transfer (CT) state at the interface between two polymer chains, which are respectively regarded as the donor and acceptor in all-polymer solar cells. The formation of a stable CT state is found to be sensitive to the distance between two oppositely charged polarons and the relevant critical electrostatic potential is thus quantified, which is in good agreement with experiments. In order to get insight into the dependence of the dissociation of the CT state on the width of the interfacial layer, two quantities are calculated: one is the Coulomb capture radius between the two polarons and the other is the quantum trace distance which serves as the fingerprint of the quantum coherence between them. The dissociation of the CT state is found to take place within an ultrafast timescale for an optimum interfacial width. The classical spatial distance and the quantum trace distance manifest a converging trend, suggesting a decoherence scenario for the charge separation in all-polymer solar cells. [ABSTRACT FROM AUTHOR]

Space Information Flow (SIF) is a new promising research area that studies network coding in geometric space, such as Euclidean space. The design of algorithms that compute the optimal SIF solutions remains one of the key open problems in SIF. This work proposes the first exact SIF algorithm and a heuristic SIF algorithm that compute min-cost multicast network coding for N (N ≥ 3) given terminal nodes in 2-D Euclidean space. Furthermore, we find that the Butterfly network in Euclidean space is the second example besides the Pentagram network where SIF is strictly better than Euclidean Steiner minimal tree. The exact algorithm design is based on two key techniques: Delaunay triangulation and linear programming. Delaunay triangulation technique helps to find practically good candidate relay nodes, after which a min-cost multicast linear programming model is solved over the terminal nodes and the candidate relay nodes, to compute the optimal multicast network topology, including the optimal relay nodes selected by linear programming from all the candidate relay nodes and the flow rates on the connection links. The heuristic algorithm design is also based on Delaunay triangulation and linear programming techniques. The exact algorithm can achieve the optimal SIF solution with an exponential computational complexity, while the heuristic algorithm can achieve the sub-optimal SIF solution with a polynomial computational complexity. We prove the correctness of the exact SIF algorithm. The simulation results show the effectiveness of the heuristic SIF algorithm. [ABSTRACT FROM AUTHOR]

• To propose novel techniques to predict greenhouse gas emissions and minimize energy consumption in renewable sources based on a sustainable environment. • The deep neural network has improved energy efficiency to predict greenhouse gas emissions using a statistic regression neural network. • This research proposed a novel technique in predicting greenhouse gas emission and minimization of energy consumption in renewable sources based on a sustainable environment. • Here, the greenhouse gas emission has been predicted using statistic regression neural network. The long-term viability of energy resources as a main input is essential to achieve long-term economic growth of a country and the energy efficiency significantly reduces energy consumption and greenhouse gas emissions, supporting environmental sustainability. As a result, a number of governments, led by those in the developed world, are making an effort to enact laws governing energy efficiency. This study suggests cutting-edge methods for forecasting greenhouse gas emissions and reducing energy demand from renewable sources based on a sustainable environment. Utilizing the statistical regression neural network (SRNN), greenhouse gas emissions have been predicted, and the deep neural network's (DNN) energy efficiency has increased. The SRNN_DNN intensity method out predicts evaluated MLR (multiple linear regression) and second- and third-order non-linear MPR (multiple polynomial regression) techniques according to MAPE (mean absolute percentage error) results. Furthermore, presented methods are considered suitable for computing GHG emissions due to the high accuracy of the SRNN DNN model. The anticipated greenhouse gas emissions related to energy were remarkably similar to the actual emissions of EU (European Union) nations. [ABSTRACT FROM AUTHOR]

The multiple-unicast network coding conjecture states that for multiple unicast sessions in an undirected network, network coding is equivalent to routing. Simple and intuitive as it appears, the conjecture has remained open since its proposal in 2004, and is now a well-known unsolved problem in the field of network coding. Based on a recently proposed tool of space information flow, we present a geometric framework for analyzing the multiple-unicast conjecture. The framework consists of four major steps, in which the conjecture is transformed from its throughput version to cost version, from the graph domain to the space domain, and then from high dimension to 1-D, where it is to be eventually proved. We apply the geometric framework to derive unified proofs to known results of the conjecture, as well as new results previously unknown. A possible proof to the conjecture based on this framework is outlined. [ABSTRACT FROM AUTHOR]

A reliable and simple modified QuEChERS method with UPLC-MS/MS was developed for the simultaneous determination of six pesticides (dimethomorph, imidaclothiz, lufenuron, methoxyfenozide, pyridaben, spinetoram) and their metabolites in pak choi. Method validation indicated good linearity (R2 ≥ 0.99), accuracy (recoveries of 75%−112%), sensitivity (limits of quantification, 0.002–0.01 mg kg−1), and precision (relative standard deviations ≤ 21%), and matrix effects were −36–28%. The half-lives of the six pesticides in pak choi were 2.2–12 d under open field and greenhouse conditions. Considering the short growth cycle of pak choi, the terminal residue levels (0.046–7.8 mg kg−1) and the relevant maximum residue limits (MRLs) of some countries, 5 d was recommended as the pre-harvest interval for the six pesticides on pak choi. Dietary risk assessment revealed that the risk quotients were 3.1%−58% for different gender and age groups in China, indicating none unacceptable public health risk for general population. The results showed that all the six pesticides degraded faster and the terminal residues were much lower under open field conditions than those under greenhouse conditions, which was mainly due to the influence of rainfall, sunlight and other environmental factors. This work was thus significant in assessing the dissipation fate and food safety risks of the six pesticides on pak choi and facilitated the establishment of maximum residue limits. • A QuEChERS method was proposed for determination of pesticides in pak choi. • The affection of different plant conditions on pesticide residues was investigated. • The dissipation and residues level in pak choi was determinate. • Dietary risk assessment was revealed between different age and gender group. [ABSTRACT FROM AUTHOR]