Driver behaviors, particularly lane-changing behaviors, have an important effect on the safety and throughput of the roadway-vehicle-based transportation system. Lane-changing models are a vital component of various microscopic traffic simulation tools, which are extensively used and playing an increasingly important role in Intelligent Transportation Systems studies. The authors conducted a detailed review and systematic comparison of existing microscopic lane-changing models that are related to roadway traffic simulation to provide a better understanding of respective properties, including strengths and weaknesses of the lane-changing models, and to identify potential for model improvement using existing and emerging data collection technologies. Many models have been developed in the last few decades to capture the uncertainty in lane change modeling; however, lane-changing behavior in the real world is very complex due to driver distraction (e.g., texting and cellphone or smartphone use) and environmental (e.g., pavement and lighting conditions) and geometric (e.g., horizontal and vertical curves) factors of the roadway, which have not been adequately considered in existing models. Therefore, large and detailed microscopic vehicle trajectory data sets are needed to develop new lane changing models that address these issues, and to calibrate and validate lane-changing models for representing the real world reliably. Possible measures to improve the accuracy and reliability of lane-changing models are also discussed in this paper.Index Terms-Driver behavior, lane-changing models.

Beneficial rhizobacteria promote plant growth and protect plants against phytopathogens. Effective colonization on plant roots is critical for the rhizobacteria to exert beneficial activities. How bacteria migrate swiftly in the soil of semisolid or solid nature remains unclear. Here we report that sucrose, a disaccharide ubiquitously deployed by photosynthetic plants for fixed carbon transport and storage, and abundantly secreted from plant roots, promotes solid surface motility (SSM) and root colonization by Bacillus subtilis through a previously uncharacterized mechanism. Sucrose induces robust SSM by triggering a signaling cascade, first through extracellular synthesis of polymeric levan, which in turn stimulates strong production of surfactin and hyper-flagellation of the cells. B. subtilis poorly colonizes the roots of Arabidopsis thaliana mutants deficient in root-exudation of sucrose, while exogenously added sucrose selectively shapes the rhizomicrobiome associated with the tomato plant roots, promoting specifically bacilli and pseudomonad. We propose that sucrose activates a signaling cascade to trigger SSM and promote rhizosphere colonization by B. subtilis. Our findings also suggest a practicable approach to boost prevalence of beneficial Bacillus species in plant protection.

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In Bacillus subtilis, robust biofilm formation requires large quantities of ferric iron. Here we show that this process requires preferential production of a siderophore precursor, 2,3dihydroxybenzoate, instead of the siderophore bacillibactin. A large proportion of iron is associated extracellularly with the biofilm matrix. The biofilms are conductive, with extracellular iron potentially acting as electron acceptor. A relatively small proportion of ferric iron is internalized and boosts production of iron-containing enzymes involved in respiratory electron transfer and establishing strong membrane potential, which is key to biofilm matrix production. Our study highlights metabolic diversity and versatile energy generation strategies within B. subtilis biofilms.

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Most DNA-based electrochemiluminescence (ECL) biosensors are established through the self-assembly of thiolated single-stranded DNA (ssDNA) probes on the Au electrode surface. Because of this random assembly process, a significant discrepancy exists in the distribution of a modified DNA film on different electrodes, which greatly affects the reproducibility of a biosensor. In this study, a porous bovine serum albumin (BSA) layer was first modified on the electrode surface, which can improve the position distribution and spatial orientation of the self-assembly ssDNA probe. It was then coupled with hyperbranched rolling circle amplification to develop the high-reproducibility-and-sensitivity ECL biosensor for human papillomavirus 16 E6 and E7 oncogene detection. In the presence of the target DNA, the surface of the electrode accumulates abundant amplified products through reaction, which contain double-stranded DNA (dsDNA) fragments of different lengths, followed by plentiful dichlorotris (1,10-phenanthroline) ruthenium­(II) hydrate (Ru­(phen)3 2+, acting as an ECL indicator) insertion into grooves of dsDNA fragments, and a strong signal can be detected. There is a linear relationship between the signal and the target concentration range from 10 fM to 15 pM, and the detection limit is 7.6 fM (S/N = 3). After the BSA modification step, the relative standard deviation was reduced from 9.20 to 3.96%, thereby achieving good reproducibility. The proposed ECL strategy provides a new method for constructing high-reproducibility-and-sensitivity ECL biosensors.

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