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Mopeds (electric bicycles and light motorcycles) are commonly used as a personal transportation mode in China. However, the understanding of characteristics of left-turning mopeds at signal-controlled intersections has been relatively limited. To bridge this gap, firstly, this paper proposed a video conversion method of moped movement data acquisition. Then, a method of data accuracy verification was introduced by comparing the results between the field experiment and the video conversion method. Secondly, the ideal traffic space for left-turn mopeds from different entrances was defined to analyse the characteristics of the left-turning mopeds at intersections. Further, three indicators, namely, transverse distance, the proportion of left-turning mopeds with crossing behaviour, and the average number of avoidance behaviour, were proposed and used to analyse the asymmetrical characteristics behaviour, crossing behaviour, and avoidance behaviour. Finally, based on empirical data collected from five signal-controlled intersections, the proposed methods and behaviours were analysed. This paper provides both a valid method of obtaining the position data of mopeds and a reliable basis for improving the safety of left-turning moped riders at urban signal-controlled intersections.

Driver sleepiness is one of the most important causes of traffic accidents. Efficient and stable algorithms are crucial for distinguishing nonfatigue from fatigue state. Relevance vector machine (RVM) as a leading-edge detection approach allows meeting this requirement and represents a potential solution for fatigue state detection. To accurately and effectively identify the driver’s fatigue state and reduce the number of traffic accidents caused by driver sleepiness, this paper considers the degree of driver’s mouth opening and eye state as multi-source related variables and establishes classification of fatigue and non-fatigue states based on the related literature and investigation. On this basis, an RVM model for automatic detection of the fatigue state is proposed. Twenty male respondents participated in the data collection process and a total of 1000 datasets of driving status (half of non-fatigue and half of fatigue) were obtained. The results of fatigue state recognition were analysed by different RVM classifiers. The results show that the recognition accuracy of the RVM-driven state classifiers with different kernel functions was higher than 90%, which indicated that the mouth-opening degree and the eye state index used in this work were closely related to the fatigue state. Based on the obtained results, the proposed fatigue state identification method has the potential to improve the fatigue state detection accuracy. More importantly, it provides a scientific theoretical basis for the development of fatigue state warning methods.

Microplastics (MPs) are ubiquitous in freshwater ecosystems, but knowledge of their effects on extracellular polymeric substance (EPS) produced by algae is poorly understood. The components in specific EPS fractions of Microcystis respond when exposed to MPs is also still unclear. In this study, the responses of Microcystis aeruginosa under polystyrene (PS) microplastic exposure were studied over 17 days of cultivation, using 0.1 μm and 1.0 μm sized PS at three concentration gradients (1, 10 and 100 mg/L). Results indicate that algal growth significantly increased using the 0.1 and 1.0 μm PS at a high concentration (100 mg/L) on day 17, with growth rates of 74.71% ± 0.94% and 35.87% ± 1.23%, respectively. All tested PS had a maximum inhibitory effect on the photosynthesis on day 5, but the inhibition of photosynthetic activity by 0.1 μm PS alleviated after 13 days of exposure, indicating recovery of microalgae from the toxic environment. The two PS sizes at 100 mg/L concentration triggered EPS release in the latter stage of the experiment; meanwhile, fluorescence EEM analysis showed that smaller-sized PS (0.1 μm) at various doses noticeably increased humic acid-like substances in tightly bound EPS (TB-EPS) fractions on day 17. Our findings showed that EPS release and humic acid-like substances secretion of Microcystis likely can resist MPs exposure. The results provide new insights into the toxicity mechanism of MPs on freshwater microalgae, as well as understanding the ecological risks of microplastics.

To determine the sources and characteristics of suspended particulate organic matter (SPOM), the spatial distribution of carbon and nitrogen and their isotopic values (δ13C and δ15N) were measured from upstreamto downstream (i.e. site 1 to site 4) in the head waters of the Qingjiang River in central China. The mean annual SPOM δ15N and δ13C values varied between sites but exhibited a unimodal pattern. The mean annual δ15N increased from site 1 (2.5‰) to 3 (5.3‰), followed by a major decrease to 2.2‰ at site 4. Furthermore, the mean annual δ13C varied unimodally, being the most positiveat sites 1 (−21.6‰) and 4 (−22.8‰) followed by sites 2 (−24.5‰) and 3 (−26.4‰). In particular, the mean SPOM δ15N and δ13C in the tailwaters from a domestic wastewater treatment plant, which was located approximately 0.3 km upstream of site 4, were 2.2‰ and −25.6‰, respectively. The SPOM C/N values from stream water at site 4 (8.5 ± 1.5) and tailwater (6.2 ± 0.9) were similar. Collectively, the results suggested that wastewater treatment plant tailwater influenced the stable isotope values of SPOM in the stream and affected the variation trendfrom upstream to downstream.

This paper discusses the construction and implementation of teeth holes filling mathod. The architecture and model of the combination of PONN multi-layer to cover teeth and fill holes of teething. Finally, the position of teeth is found, and the tooth model is placed through 3D space. Experimental results show that the method has good expansibility and superiority.

A new force is introduced in the social force model (SFM) for computing following behavior in pedestrian counterflow, whereby an individual tries to approach others in the same direction to avoid conflicts with pedestrians from the opposite direction. The force, like a kind of gravitation, is modeled based on the movement state and visual field of the pedestrian, and is added to the classical SFM. The modified model is presented to study the impact of following behavior on the process of lane formation, the conflict, the number of lanes formed, and the traffic efficiency in the simulations. Simulation results show that the following behavior has a significant effect on the phenomenon of lane formation and the traffic efficiency.

In order to solve the problems of low utilization rate of large parking lots and low efficiency of parking turnover, it is proposed to use A-star algorithm to plan the shortest path for finding a car, and run it in Android system to realize reverse car-searching. By analyzing the current situation of large underground parking lot barriers, A-star algorithm converts the starting point to the destination route into the corresponding parking space to the destination parking space path, calculates the optimal path and provides real-time path car navigation for the vehicle owner. According to the path searched by the A-star algorithm in the Android system, the time spent by the user to blindly search for the vehicle is largely saved, and the parking space utilization rate and the parking turnover rate are effectively improved. Therefore, the research has certain application value in the large parking lots.

In this study, polyethylene filter cotton (PFC) was used as a suspended biocarrier to remove ammonium from aquaculture ponds. The concentration of the ammonia-oxidizing bacteria (AOB amoA gene reached ~107 copies cm−3 in the PFC after 16–19 days of incubation, whereas only 101–102 copies cm−3 were present in the aquaculture water. The effects of temperature, pH, and dissolved oxygen (DO) concentration on the nitrification rate were evaluated in the laboratory. The nitrification rate of PFC enriched with AOB reached 0.035 ± 0.002 mg N cm−3 PFC h−1 measured at pH 7.0–8.5, 28 °C, and a DO concentration of 6.0–7.0 mg L−1. These results suggest that the use of PFC as a suspended biocarrier in aquaculture ponds is a feasible and cheap method for removing ammonium ion in situ.

The nonpayment area at urban transit stations in China usually becomes extremely crowded during peak hours because many passengers queue to buy tickets and pass through the fare gates. How to evaluate the performance of these activities is a critical issue for the design and management of the nonpayment area. This study used microscopic simulation models to investigate passenger behavior in the nonpayment area. The study developed a queue choice model, a passenger movement model, and a path navigation model. Some new ideas were involved. First, the study introduced the concepts of dynamic queue length and dynamic distance between the current passenger and alternative queues into the queue choice model. Second, a new factor, called direction of goal, was proposed to navigate a passenger through the dynamic end of a queue or other goals. This factor was used to construct the transition probability function of a cellular automata model. Finally, the proposed models were calibrated and verified on the basis of a field survey and sensitivity analysis. The results show that the proposed models can capture passenger behaviors in the nonpayment area and perform well for queue estimation.

An annual investigation into the abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in fresh water aquaculture ponds was performed by quantitative PCR of the amoA gene. The results showed that AOB were the main ammonia-oxidizing microorganisms in water, and significantly higher copy numbers of the AOB amoA gene were observed in the summer (Aug 2012), while no significant differences were detected among the other three seasons. AOA showed low abundances throughout the year. The predominance of AOB in aquaculture water was suggested to be related to photoinhibition. Both the AOB and AOA amoA genes in aquaculture pond sediments showed typical seasonal patterns. The maximum density of AOB was observed in the autumn (Nov 2012) and winter (Jan 2013), while the maximum density of AOA was observed in winter. The minimum densities of both AOA and AOB occurred in the summer. The concentration of the AOA amoA gene was higher than that of the AOB amoA gene in sediments by almost one order of magnitude, which indicates that AOA are the dominant ammonia-oxidizing microorganisms in the aquaculture pond sediments. Dissolved oxygen is suggested to be the key factor determining the predominance of AOA in pond sediments.

The configuration of service facilities, such as ticket vending machines, staffed ticket booths, automatic fare gates, and escalators, is an important issue for the plan and design of rail transit stations. Reasonable configuration of service facilities is based on a good understanding of the passenger traffic characteristics of such service facilities, which are affected by passenger characteristics, station types, and facility performance. To study the passenger traffic characteristics of service facilities, five stations are selected in Shanghai, and their passenger traffic data are collected and analyzed. In this study, the results indicate that service-time frequencies of ticket vending machines and staffed ticket booths follow Weibull distribution and exponential distribution, respectively, and that the headway of passengers passing the automatic fare gate under ideal conditions follows normal distribution. According to the service time and headway distributions of ticket-selling facilities ...

Ethanol is a neuroteratogen and neurodegeneration is the most devastating consequence of developmental exposure to ethanol. The mechanisms underlying ethanol-induced neurodegeneration are complex. Ethanol exposure produces reactive oxygen species (ROS) which cause oxidative stress in the brain. We hypothesized that ethanol would activate autophagy to alleviate oxidative stress and neurotoxicity. Our results indicated that ethanol increased the level of the autophagic marker Map1lc3-II (LC3-II) and upregulated LC3 puncta in SH-SY5Y neuroblastoma cells. It also enhanced the levels of LC3-II and BECN1 in the developing brain; meanwhile, ethanol reduced SQSTM1 (p62) levels. Bafilomycin A(1), an inhibitor of autophagosome and lysosome fusion, increased p62 levels in the presence of ethanol. Bafilomycin A(1) and rapamycin potentiated ethanol-increased LC3 lipidation, whereas wortmannin and a BECN1-specific shRNA inhibited ethanol-promoted LC3 lipidation. Ethanol increased mitophagy, which was also modulated by BECN1 shRNA and rapamycin. The evidence suggested that ethanol promoted autophagic flux. Activation of autophagy by rapamycin reduced ethanol-induced ROS generation and ameliorated ethanol-induced neuronal death in vitro and in the developing brain, whereas inhibition of autophagy by wortmannin and BECN1-specific shRNA potentiated ethanol-induced ROS production and exacerbated ethanol neurotoxicity. Furthermore, ethanol inhibited the MTOR pathway and downregulation of MTOR offered neuroprotection. Taken together, the results suggest that autophagy activation is a neuroprotective response to alleviate ethanol toxicity. Ethanol modulation of autophagic activity may be mediated by the MTOR pathway.

Subchronic exposure to arsenic increases the incidence of human cancers such as skin, lung, colon, and rectal cancer. The mechanism for arsenic-induced tumorigenesis is still not clear. It is generally believed that DNA damage and genomic instability, generated by arsenic-promoted oxidative stress, account largely for this process. The major sources of reactive oxygen species (ROS) are arsenic-damaged mitochondria. Autophagy is a catabolic process functioning in turnover of long-lived proteins and dysfunctional organelles such as mitochondria. Defects of autophagy under stress conditions promote genomic instability and increase the risk of tumorigenesis. In the present study using a human bronchial epithelial cell line, BEAS-2B cells, we investigated the role of autophagy in arsenic-induced cell transformation, an important step in arsenic tumorigenesis. Our results show that subchronic arsenic exposure induces BEAS-2B cell transformation accompanied with increased ROS generation and autophagy activation. However, the patterns for ROS and autophagy alteration are different. Arsenic exposure generated a prolonged and steady increase of ROS levels, whereas the activation of autophagy, after an initial boost by arsenic administration, decreases in response to subchronic arsenic exposure, although the activity is still higher than a nontreated control. Further stimulation of autophagy increases mitochondria turnover and decreases ROS generation and arsenic-induced cell transformation. Contrarily, inhibition of autophagy activity decreases mitochondria turnover and enhances arsenic-induced ROS generation and cell transformation. In addition, the mammalian target of rapamycin signaling pathway is involved in arsenic-mediated autophagy activation. Our results suggest that autophagy is a cell self-protective mechanism against arsenic-induced cell transformation.

The experimental control of gene expression in specific tissues or cells at defined time points is a useful tool for the analysis of gene function. GAL4/VP16-UAS enhancer trap lines can be used to selectively express genes in specific tissues or cells, and an ethanol-inducible system can help to control the time of expression. In this study, the combination of the two methods allowed the successful regulation of gene expression in both time and space. For this purpose, a binary vector, 962-UAS::GUS, was constructed in which the ALCR activator and beta-glucuronidase (GUS) reporter gene were placed under the control of upstream activator sequence (UAS) elements and the alcA response element, respectively. Three different GAL4/VP16-UAS enhancer trap lines of Arabidopsis were transformed, resulting in transgenic plants in which GUS activity was detected only on ethanol induction and exclusively in the predicted tissues of the enhancer trap lines. As a library of different enhancer trap lines with distinct green fluorescent protein (GFP) patterns exist, transformation with a similar vector, in which GUS is replaced by another gene, would enable the control of the time and place of transgene expression. We have constructed two vectors for easy cloning of the gene of interest, one with a polylinker site and one that is compatible with the GATEWAY vector conversion system. The method can be extended to other species when enhancer trap lines become available.

Clonal fragments of the stoloniferous herb Glechoma longituba were subjected to a complementary patchiness of light and soil nutrients including two spatially homogeneous treatments (SR–SR and IP–IP) and two spatially heterogeneous treatments (IP–SR and SR–IP). SR and IP indicate patches (shaded, rich) with low light intensity (shaded, S), high nutrient availability (rich, R) and patches (illuminated, poor) with high light intensity (illuminated, I) and low nutrient availability (poor, P), respectively. Plasticity of the species in root–shoot ratio, fitness-related traits (biomass, number of ramets and dry weight per ramet) and clonal morphological traits (length and specific length of stolon internodes, area and specific area of laminae, length and specific length of petioles) were experimentally examined. The aim is to understand adaptation of G. longituba to the environment with reciprocal patches of light and soil nutrients by plasticities both in root–shoot ratio and in (clonal) morphology. Our experiment revealed performance of the clonal fragments growing from patches with high light intensity and low soil nutrient availability into the adjacent opposite patches was increased in terms of the fitness-related characters. R/S ratio and clonal morphology were plastic. Meanwhile, the capture of light resource from the light-rich patches was enhanced while the capture of soil nutrients from either the nutrient-rich or the nutrient-poor patches was not. Analysis of cost and benefit disclosed positive effects of clonal integration on biomass production of ramets in the patches with low light intensity and high soil nutrient availability. These results suggest an existence of reciprocal translocation of assimilates and nutrients between the interconnected ramets. The reinforced performance of the clonal fragments seems to be related with specialization of clonal morphology in the species.

Ultraviolet B (UVB) exposure causes damage to skin and represents the primary etiological agent for skin cancer formation. UVB induces DNA damage and apoptosis in epidermal cells. In this study, we demonstrated that UVB activated autophagy in JB6 epidermal cells, which was evident by the formation of LC3 puncta, the induction of LC3 lipidation, the increase in beclin 1 expression, and the decrease in the levels of p62. Autophagy appeared to be a protective response to UVB-induced damage because inhibition of autophagy exacerbated UVB-induced cell death, and stimulation of autophagy offered protection. Furthermore, we demonstrated that glycogen synthase kinase 3β (GSK3β) was involved in UVB-induced autophagy. UVB inhibited GSK3β activation by simultaneously enhancing phosphorylation at Ser9 and suppressing Tyr216 phosphorylation. GSK3β negatively regulated autophagy; overexpression of wild‑type or S9A (constitutive-active) GSK3β mutant inhibited UVB-mediated autophagy, while overexpression of a dominant-negative K85R mutant enhanced UVB-mediated autophagy. Inhibition of GSK3β also offered protection against UVB-mediated damage. UVB activated AMP-activated protein kinase (AMPK), an important regulator of autophagy through the inhibition of GSK3β. Taken together, our results suggest that UVB-stimulated autophagy is a protective response for epidermal cells and is mediated by the GSK3β/AMPK pathway.

Both epidemiological and experimental studies indicate that ethanol exposure enhances tumor progression. Ethanol exposure promotes cancer cell invasion and is implicated in tumor metastasis. Metastasis consists of multiple processes involving intravasation and extravasation of cancer cells across the blood vessel walls. The integrity of the vascular endothelial barrier that lines the inner surface of blood vessels plays a critical role in cancer cell intravasation/extravasation. We examined the effects of ethanol on the endothelial integrity in vitro. Ethanol at physiologically relevant concentrations did not alter cell viability but disrupted the endothelial monolayer integrity, which was evident by a decrease in the electric resistance and the appearance of intercellular gaps in the endothelial monolayer. The effect of ethanol was reversible once ethanol was removed. The disruption of the endothelial monolayer integrity was associated with an increased invasion of cancer cells through the endothelial monolayer. Ethanol induced the formation of stress fibers; stabilization of actin filaments by jasplakinolide prevented ethanol-induced disruption of endothelial integrity and cancer cell invasion. VE-cadherin is a critical component of the adherens junctions, which regulates vascular endothelial integrity. Ethanol induced the endocytosis of VE-cadherin and the effect was blocked by jasplakinolide. Our results indicate that ethanol may facilitate cancer metastasis by disrupting the vascular endothelial barrier.

Sterol 14alpha-demethylase (CYP51), the most widely distributed member of the P450 superfamily, is the key enzyme in sterol biosynthesis pathway. CYP51 is not only an important model for fundamental P450 structure/function studies, but also an important target protein of cholesterol-lowering agents, antifungal drugs and herbicides. This article reviewed the research advances in CYP51 at various aspects, including sequence characteristics, physiological roles, catalytic properties in vitro, protein structure, structure-function relationships and inhibition of CYP51. The problems remained in current research and designations of CYP51 inhibitors are also discussed.

BACKGROUND:Magnaporthe grisea (Hebert) ME Barr infection is one of the most serious diseases for cultivated rice in the world. Sterol 14α-demethylase (CYP51) is an important drug target for microbial pathogenic infections. To exploit specific and effective fungicides for M. grisea better, the authors have analysed the characteristics of interaction between sterol 14α-demethylase from M. grisea (MGCYP51) and azoles. MGCYP51 with truncation of N-terminal residues was cloned and expressed in E. coli, difference binding spectra of MGCYP51 induced by addition of four commercial azoles were determined and molecular modelling of MGCYP51 based on the crystal structure of Mycobacterium tuberculosis Lehmann & Newman and docking with the azoles were performed. RESULTS: The affinity of the azoles for MGCYP51 was positively correlated with their hydrophobicity. Amino acid residues Tyr112, Phe120, Phe220, His308 and Phe497 of MGCYP51, forming a large hydrophobic cavity, are the key residues interacting with azole fungicides. Furthermore, Phe220 and Phe497 are fungus and species specific respectively. CONCLUSION: The results suggest that the more potent azole fungicides for MGCYP51 should possess more hydrophobic groups interacting with residues Phe220 and Phe497. Copyright © 2009 Society of Chemical Industry

Rice blast, caused by the ascomycete fungus Magnaporthe grisea, is one of the most serious diseases for cultivated rice. Sterol 14 alpha-demethylase (CYP51) is one of the key enzymes of sterol biosynthesis in biological kingdoms and an important drug target for microbial pathogenic infections. In the present study CYP51 with truncation of N-terminal residues from M. grisea (MGCYP51) was cloned and expressed in E. coli, drug binding spectrum of MGCYP51 induced by addition of diniconazole was determined. In order to exploit more selective and effective fungicides for M. grisea, homology model of MGCYP51 was established based on crystal structure of Mycobacterium tuberculosis and diniconazole was docked into the active site by FlexX. The spectral data showed that diniconazole exhibited a high affinity for MGCYP51, coincided with the implication of molecular docking. The results in a way elucidated the reasonability and reliability of the 3D model and docking model, which can be hopefully used to virtually screen the more potent azole fungicides for MGCYP51.

Agroinfiltration is employed as a fast way to directly create marker-free transgenic tobacco plants. As an example for the efficiency of the method, Agrobacterium cells harboring a marker-free vector coding for beta-glucuronidase (GUS) were infiltrated into the leaf discs of Nicotiana tabacum, which were then used as explants for marker-free plant regeneration by tissue culture. Through GUS staining, a large number of small calli were shown to be stably transformed on the treated leaf discs at 17 days after agroinfiltration. Most importantly, after continuous culture of the leaf discs until shoot regeneration, about 15% of the regenerants were proven to be transformants by polymerase chain reaction (PCR) analysis.