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Lane markings are considered an essential component of a road system. As highlighted in previous studies, they are directly linked to efficiency and safety. The rearrangement or reallocation of lane markings can be an economical way to improve efficiency. However, such changes could influence driver behavior. Thus, there is a tradeoff between efficiency and safety. Through a case study in Kochi City, Japan, this study evaluated the change in crash risk caused by a lane marking reallocation. Video data were collected before and after the implementation of a new road layout (achieved by reallocating lane markings) that was intended to mitigate traffic congestion at a signalized intersection. Based on the video data, PICUD (Possibility Index for Collision with Urgent Deceleration), a surrogate safety index used to estimate collision risk, was estimated for lane changes and conflicts between leading and following vehicles in the through lane. In particular, it was confirmed that the collision risk between a lane-changing vehicle and a leading vehicle in the through lane was reduced due to the reduction in traffic density caused by the new road layout. In addition, the results indicate that the PICUD value tends to decrease (i.e., the crash risk tends to increase) with increasing speed of the following vehicle relative to the leading vehicle. Overall, the improvement in safety after the implementation of the new road layout was marginal and statistically insignificant. Therefore, this study highlights the necessity of incorporating speed control measures, such as speed limits, along with congestion alleviation measures in order to enhance safety. • The change in crash risk caused by lane marking reallocation was evaluated using a surrogate safety indicator named PICUD. • Video data were collected before and after the implementation of a new lane marking scheme at a signalized intersection. • Rear vehicles that interact with lane-changing front vehicles displayed a higher collision risk. • With congestion alleviation measures, e.g., lane marking reallocations, speed control measures should also be implemented to enhance safety. [ABSTRACT FROM AUTHOR]

This study investigates the relative importance of ‘metric distance’(MD),‘topological distance’(TD) and ‘geo-metrical distance’(GMD) in determining the route choice behavior of motorized travelers by mode. The study is based on data which has traced the travelers’ actual movements by using mobile GIS applications. MD, TD and GMD were calculated based on space syntax tool within a GIS environment. The findings indicated that GMD is more appropriate than MD in case of travelers’ who use car and motorcycle, whereas MD is more appropriate than GMD travelers’ who use PT and taxi for mode choice modeling, travel demand simulations and automobile navigation systems. [ABSTRACT FROM AUTHOR]

Gamma-glutamylcysteine (γ-GC), the precursor of glutathione (GSH), may have significant health benefits as a dietary supplement, but there are few cost-effective methods available for its large-scale production. We developed an efficient method for producing γ-GC in a mutant yeast strain using a three-step breeding procedure and a unique cultivation process. In the first breeding step, we prepared a glutathione synthetase (GSH2)-deficient yeast mutant. In the second step, selenate () sensitivity was introduced by crossing the GSH2-deficient mutant with a strain harboring the met30 mutation. In the final step, pantothenic acid auxotrophy was introduced by ethyl methanesulfonate mutagenesis. The isolated strain displayed significantly enhanced cellular γ-GC when cultivated in synthetic medium without pantothenic acid, reaching a maximum level of 4.39% of dry cell weight. Using this strain, we were able to prepare a yeast extract containing approximately 13% γ-GC (w/w), which is markedly higher than the reported value (0.3%) of commercially available yeast extracts. The present method may facilitate large-scale γ-GC production for investigating the nutritive value and other benefits of dietary γ-GC. [ABSTRACT FROM AUTHOR]

Personal mobility vehicles (PMVs) are gaining popularity as an eco-friendly transport mode for short-distance trips in urban environments. These vehicles can provide numerous economic, environmental, and social benefits and are likely to become more common in urban spaces in the near future. Before permitting them in shared environments, the impacts of the PMVs on the other users of the shared space should be properly evaluated, particularly from a safety perspective. This study focuses on pedestrians’ danger perception toward PMVs interacting with them in shared spaces. To estimate the perceived danger, a model was developed. The developed model is inspired by the social-force concept, and it estimates a safety index called subjective danger index (SDI). The model is then calibrated with data collected through controlled laboratory experiments. The experiments revealed two important features of the pedestrians’ subjective danger perception against PMVs. First, the pedestrians' sensitivity to the distance between a PMV and them is higher when the PMV is in front of them compared to when it is behind them. Secondly, pedestrians perceive a PMV in front of them as more dangerous compared to a PMV behind them when they are near the PMV, although they perceive higher danger when a PMV is approaching from behind them compared to when a PMV is approaching from the front of them when they are relatively far from the PMV. The calibration results demonstrate that the enhanced model can accurately capture such trends and therefore the perception of danger. A case study that uses experimental trajectory data from a PMV–pedestrian interaction situation is also presented to clarify potential applications, characteristics, and limitations of the calibrated SDI model. [ABSTRACT FROM AUTHOR]

We identified Saccharomyces cerevisiae mutants with 100% higher intracellular glutathione using 1-methyl-3-nitro-1-nitrosoguanidine mutagenesis. This method employs visual selection of the most pigmented colonies among met30 strains carrying ade1 and ade2 mutations. Since the method does not involve genetic engineering, the mutants are suitable for use in the food industry. [ABSTRACT FROM AUTHOR]

Abstract: A strategy has been developed for creating Saccharomyces cerevisiae strains with a high RNA content by following a three-step breeding procedure. In the first step, an S. cerevisiae disruptant of the RRN10 gene, one of the components of the UAF (upstream activation factor) complex of rRNA transcription, was constructed and showed severely slow growth. In the second step, seven suppressors were isolated that restored the slow growth of the Δrrn10 disruptant. Genetic analysis revealed that each of the seven suppressors that were isolated appeared to have dominant and multiple mutations. The specific growth rate of those suppressors was increased approximately two-fold as compared with the Δrrn10 parental strain. The absolute RNA content showed that the suppressors had an RNA content 32–56% higher than that of the Δrrn10 parental strain. In the last step, the RRN10 wild-type gene was integrated into chromosome V of each of the original suppressors. The total RNA content of the integrants was also 1.4- to 2.3-fold higher than the wild-type strain. In conclusion, since yeast RNA is the source of 5′-IMP and 5′-GMP that enhance the delicious taste in certain types of food, like soups and sauces, the strategy taken in this study provides effective approach to breed S. cerevisiae strains producing a higher content of RNA that will contribute to yeast food biotechnology. [Copyright &y& Elsevier]

Glutathione overproducers were detected by examining the pigmentation intensity of Saccharomyces cerevisiae met30 yeast carrying wild-type alleles for ADE1 and ADE2. Highly pigmented colonies, phenocopies of the ade2 or ade1 mutants, were observed among yeast grown in minimal biotin-free medium with a high methionine content. [ABSTRACT FROM AUTHOR]