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Taking real-time and effective preventive maintenance measures on in-service roads can reduce traffic congestion, eliminate potential road safety hazards, and greatly reduce road maintenance costs. Therefore, based on the Persson friction theory, this study first determines the evaluation indicators for the anti slip ability of asphalt pavement. And based on vehicle dynamics and contact friction between tires and road surface, the anti-skid thresholds of road surfaces for different road conditions and vehicle models are solved through simulation. This study utilizes Python and neural network algorithms to establish a decision-making model for anti-slip recovery technology of asphalt pavement. The experiment shows that the model trained by Back Propagation neural network has high accuracy. The training accuracy of the model is stable at around 0.90, and the training loss value is around 0.34, which can be used for decision-making in anti slip recovery technology. When the speed is less than 60 km/h, the increase in the threshold of dynamic friction coefficient is significant. The maximum difference in growth rate is 47.9%. When the speed exceeds 60 km/h, the increase in the threshold of dynamic friction coefficient gradually slows down. Therefore, at lower speeds, it is more essential to consider the variable value of the dynamic friction coefficient. When the speed is high, more consideration needs to be given to its reference value. This study provides a scientific basis for ensuring that the anti slip ability of the road surface always meets the requirements of driving safety, and has important engineering practical value, economic and social benefits. [ABSTRACT FROM AUTHOR]

Mesoporous WO3 (m-WO3) was synthesized by a hydrothermal method using mesoporous silica KIT-6 as a hard template and silicotungstic acid as a precursor. The m-WO3modified by molybdenum (Mo) nanoparticles could be used as a stable catalyst for photo-thermal inducing CO2reducting reactions for solar fuels. Under visible light irradiation (γ > 420 nm) and 250-, the catalytic activity of m-Mo/WO3 for the CH4 and CH4OHevolution was found to be higher than that of m-WO3 and commercial WO3. The amount of evolved CH3OH from m-Mo/WO3has reached 13.80 /umolg-1 in 12 h, which is ca.10 times as high as that of c-WO3(1.36 yumolg-1) and 6.5 times as high as that of m -WO3 (2.12 μmolg-1), making it attractive for practical applications. [ABSTRACT FROM AUTHOR]

Demand-responsive feeder transit (DRFT) is an emerging urban public transport mode with the advantage of offering flexible door-to-door services in the high-speed railway hub area. However, the existing bus scheduling schemes can hardly meet personalized and diversified passenger transfer demands in the station-city integrated high-speed railway hub, reducing the attractiveness of DRFT. This paper studies the DRFT scheduling problem considering static and dynamic travel demands under the background of mobility as a service (MaaS). An information-based DRFT system framework is proposed, where the K-means clustering algorithm is implemented to select target bus stops from regional road networks for passengers to get on and off. A two-stage mixed integer programming model is first formulated to generate operational routes and optimize the static and dynamic scheduling before and after departure. The objective functions reflect the operating benefits of public transport enterprises and the travel costs of passengers, and the demand characteristics in different driving directions are taken into account in the model. Then, an improved genetic algorithm is developed to solve the model, which is called the genetic algorithm-exact algorithm (GA-EA) in this paper. Finally, the proposed model and algorithm are evaluated using the case study of the Nanjingnan Railway Station area. The experiment results show that the optimal scheme can provide a 100% demand-response rate, reasonable service time, and valid driving routes. In addition, compared with GA, the average search time of GA-EA is shortened by 43.5% and the total objective function value is increased by 2.16%. The findings in this paper can provide practical guidance on DRFT scheduling and improve the efficiency of bus feeder service. [ABSTRACT FROM AUTHOR]

Investigations into the role of hypoxia have concentrated on hypoxic damage to cells and the associated adaptative mechanisms, however, the effects of hypoxia on cell proliferation and differentiation have received less attention. The present study aimed to investigate the role of hypoxia on the proliferation of MC3T3-E1 cells and examine the molecular mechanism involved. Cells treated with low levels of hypoxia had an increased percentage of S phase cells and a decreased percentage of G1 phase cells, promoted the level of cell proliferation-associated proteins, proliferating cell nuclear antigen and cyclin D. In addition, hypoxia increased cell proliferation by upregulating the expression of hypoxia-inducible factor (HIF)-1a. The phosphoinositide 3-kinase/Akt and mitogen-activated protein kinase/extracellular signal-regulated kinase pathways augmented the expression of HIF-1a in the MC3T3-E1 cells. The present study demonstrated that hypoxia induces positive effects on osteoblast proliferation, suggesting a novel strategy in the treatment of osteoporosis. [ABSTRACT FROM AUTHOR]

Lipid coverage is crucial in comprehensive lipidomics studies challenged by high diversity in lipid structures and wide dynamic range in lipid levels. Current state-of-the-art lipidomics technologies are mostly based on mass spectrometry (MS), including direct-infusion MS, chromatography-MS, and matrix-assisted laser desorption ionization (MALDI) imaging MS, each with its pros and cons. Due to the need or favorability for measurement of isomers and isobars, chromatography-MS is preferable for lipid profiling. The ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLCHRMS)- based nontargeted lipidomics approach and UHPLCtandem MS (UHPLC-MS/MS)-based targeted approach are two representative methodological platforms for chromatography-MS. In the present study, we developed a high coverage pseudotargeted lipidomics method combining the advantages of nontargeted and targeted lipidomics approaches. The high coverage of lipids was achieved by integration of the detected lipids derived from nontargeted UHPLC-HRMS lipidomics analysis of multiple matrices (e.g., plasma, cell, and tissue) and the predicted lipids speculated on the basis of the structure and chromatographic retention behavior of the known lipids. A total of 3377 targeted lipid ion pairs with over 7000 lipid molecular structures were defined. The pseudotargeted lipidomics method was well validated with satisfactory analytical characteristics in terms of linearity, precision, reproducibility, and recovery for lipidomics profiling. Importantly, it showed better repeatability and higher coverage of lipids than the nontargeted lipidomics method. The applicability of the developed pseudotargeted lipidomics method was testified in defining differential lipids related to diabetes. We believe that comprehensive lipidomics studies will benefit from the developed high coverage pseudotargeted lipidomics approach. [ABSTRACT FROM AUTHOR]

Carnitines play important roles in fatty acid oxidation and branched chain amino acid metabolism. The disturbance of acylcarnitines is associated with occurrence and development of many diseases. Comprehensive acylcarnitine identification can greatly benefit their targeted detection, following disease differential diagnosis and possible mechanism study. In this study, we developed a novel strategy to identify as many acylcarnitines as possible based on liquid chromatography-highresolution mass spectrometry (LC-HRMS). The layer-layer progressive strategy first integrated the initial full scan MS/data-dependent MS/MS monitoring (ddMS²) acquisition and the following parallel reaction monitoring (PRM) to analyze a pooled biological sample. Also 733 possible acylcarnitines were identified containing characteristic high-resolution MS/MS features. Further, accurate mass, retention rules, and HRMS/MS information were used to define subclasses and predict undetected acylcarnitine homologues in each subclass, leading to more acylcarnitines to our newly constructed database. As a result, 758 acylcarnitines were contained in the database, having exact mass, retention time, and MS/MS information, which is the most comprehensive list of acylcarnitines reported to date. Applying this database, 241, 515, and 222 acylcarnitines were rapidly and reliably annotated in human plasma, human urine, and rat liver tissue. This novel strategy enables large-scale identification of acylcarnitines, and a similar method can also be used for identification of other metabolites. [ABSTRACT FROM AUTHOR]

Zipf's law is an important linguistics law. In 1940s, Zipf found power law in the distribution of the word frequencies. The word rankings are in descending order of their occurrence frequencies. Through a series of experiments of random input letter sequences, the results show that the power law distribution has existed in not only natural language utterances but also random symbolic sequences. [ABSTRACT FROM AUTHOR]

The expression and correlation analysis of the regenerating gene family member 4 (RegIV) and vascular endothelial growth factors (VEGF-A and VEGF-C) in metastatic spinal tumors were studied. Fifteen patients with metastatic spinal tumors who underwent operation in our hospital from January 2011 to January 2013 were selected into this study. The expression level of tumor tissues in patients with spinal metastasis and RegIV, VEGF-A and VEGF-C of the corresponding paracancer normal tissue samples were evaluated by immunohistochemical staining method and the correlation between the expression of RegIV, VEGF-A and VEGF-C was analyzed. qRT-PCR results showed that the expression of RegIV was increased (P<0.05) in paracancer normal tissues and spinal metastatic tumor tissues. Compared with normal tissues, expression of RegIV, VEGF-A and MicroRNAs (miRs) can function as tumor suppressors or oncogenes in different types of human malignancy, and may provide an effective therapy for cancer. The expression and functions of miR-592 have previously been studied in relation to cancer. However, the expression and potential functions of miR-592 in hepatocellular carcinoma (HCC) are still unknown. Using quantitative polymerase chain reaction, MTT assays, cellular migration and invasion assays, bioinformatics software, western blot analysis and dual-luciferase report assays, the present study explored the expression and roles of miR-592 in HCC. It was identified that miR-592 was significantly downregulated in HCC tissues and cell lines. The statistical analysis revealed that low expression of miR-592 was evidently associated with tumor node metastasis stage and lymph node metastasis. Additionally, the present study provided the first evidence that miR-592 was likely to directly target the insulin-like growth factor 1 receptor in vitro. The present results indicated that miR-592 could be investigated as an efficacious therapeutic target for HCC in the future. [ABSTRACT FROM AUTHOR]

A seriesof cobalt-based catalysts supported on several acidic/basicoxides were prepared by the incipient wetness impregnation methodand applied for the one-pot synthesis of isophorone diamine (IPDA)from hydroamination of isophorone nitrile (IPN). The effects of thesupports and cobalt loading on the performance of the catalysts wereinvestigated. The results showed that the Co/SiO2catalystwith 20 wt % Co loading gave the highest conversion of IPN (90.9%)and yield of IPDA (70.4 mol %) among the supported cobalt catalystsused in this work, and it could be reused eight times without a significantdecrease in the catalytic performance, which was much better thanthat from the commercial Raney Co. Meanwhile, the possible intermediatesand reaction pathways during hydroamination of IPN were provided. [ABSTRACT FROM AUTHOR]