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Cycling can bring a wide range of social, economic, and health benefits to individuals and communities. The safety and efficiency of bicycle facilities can be significantly impacted by the interactions among riders. This study aims to examine the microscopic characteristics of how cyclists interact with each other when they are in a single file movement based on the trajectory data collected from an experiment. Reaction delay was obtained by optimizing the correlation between relative speed and acceleration curves for individual cyclists and it was found that even for a given cyclist, this characteristic time delay could vary considerably, and be situation-dependent. Furthermore, it was found that the distribution of reaction delay, which has an average (±SD) of 0.66 s (±0.33 s), followed a log-normal distribution. The strong correlation observed between relative speed and time-delayed acceleration resembles the behavior observed in car-following situations, highlighting that relative speed is an essential factor influencing the acceleration behavior of cyclists. Multiple linear regression models were used to understand the association between acceleration and other key microscopic variables, e.g., spacing and relative speed, which are commonly used in microscopic behavior models. While the spacing between cyclists was found to have a significant impact on acceleration behavior, its effect was not as significant as that of relative speed. The outcomes of this study provide valuable insights into the cyclists' behavior and can aid in the development of microscopic simulation models. [ABSTRACT FROM AUTHOR]

It is anticipated that the prevalence of motorcycles in Asian countries will continue to increase, causing congestion and network imbalances concerning the nature of motorcycles. Literature demonstrates Variable Message Signs (VMSs) as an effective measure for addressing this issue. Understanding route choice behavior may thus aid in determining the appropriate traffic information to broadcast. This study aims to identify the impact of VMS messages related to traffic conditions and regulations on the route choice of motorcycle riders. In this instance, the core concept of ramp metering is adapted for non-highways to manage the proportion of motorcycles entering the traffic stream of the mainline. Two predetermined routes were offered through a stated preference survey to capture the responses to VMS. A binary logit model was initially introduced, further improved by including the individual characteristics and accommodating the unobserved factors across a series of observations (panel effects) by applying the mixed binary logit. It was revealed that traffic flow conditions significantly affect route preference; therefore, motorcycles tend to choose routes with lower volumes. However, waiting time at a ramp meter has no impact. The present research is a preliminary investigation for further implications in proposing traffic management strategies under mixed traffic situations. [ABSTRACT FROM AUTHOR]

To deal with recent increasing mobile traffic, ultra-broadband communication with millimeter-wave (mmWave) has been regarded as a key technology for 5G cellular networks. In a previous study, a mmWave heterogeneous network was composed of several mmWave small cells overlaid on the coverage of a macro cell. However, as seen from the optical fiber penetration rate worldwide, it is difficult to say that backhaul with Gbps order is available everywhere. In the case of using mmWave access under a limited backhaul capacity, it becomes a bottleneck at the backhaul; thus, mmWave access cannot fully demonstrate its potential. On the other hand, the concept of multi-access edge computing (MEC) has been proposed to decrease the response latency compared to cloud computing by deploying storage and computation resources to the user side of mobile networks. This paper introduces MEC into mmWave heterogeneous networks and proposes a content prefetching algorithm to resolve such backhaul issues. Context information, such as the destination, mobility, and traffic tendency, is shared through the macro cell to the prefetch application and data that the users request. Prefetched data is stored in the MEC and then transmitted via mmWave without a backhaul bottleneck. The effectiveness is verified through computer simulations where we implement realistic user mobility as well as traffic and backhauling models. The results show that the proposed framework achieved 95% system capacity even under the constraint of a 1 Gbps backhaul link. [ABSTRACT FROM AUTHOR]

The role of glutathione (GSH) in eukaryotic cells is well known. The biosynthesis of this γ-glutamine tripeptide is well studied. However, other γ-glutamyl peptides were found in various sources, and the pathways of their formation were not always clear. The aim of the present study was to determine whether Saccharomyces cerevisiae can produce γ-glutamyl tripeptides other than GSH and to identify the pathways associated with the formation of these peptides. The tripeptide γ-Glu-Val-Gly (γ-EVG) was used as a model. Wild-type yeast cells were shown to produce this peptide during cultivation in minimal synthetic medium. Two different biosynthetic pathways for this peptide were identified. The first pathway consisted of two steps. In the first step, γ-Glu-Val (γ-EV) was produced from glutamate and valine by the glutamate-cysteine ligase (GCL) Gsh1p or by the transfer of the γ-glutamyl group from GSH to valine by the γ-glutamyltransferase (GGT) Ecm38p or by the (Dug2p-Dug3p)2 complex. In the next step, γ-EV was combined with glycine by the glutathione synthetase (GS) Gsh2p. The second pathway consisted of transfer of the γ-glutamyl residue from GSH to the dipeptide Val-Gly (VG). This reaction was carried out mainly by the (Dug2p-Dug3p)2 complex, whereas the GGT Ecm38p did not participate in this reaction. The contribution of each of these two pathways to the intracellular pool of γ-EVG was dependent on cultivation conditions. In this work, we also found that Dug1p, previously identified as a Cys-Gly dipeptidase, played an essential role in the hydrolysis of the dipeptide VG in yeast cells. It was also demonstrated that γ-EV and γ-EVG could be effectively imported from the medium and that γ-EVG was imported by Opt1p, known to be a GSH importer. Our results demonstrated that γ-glutamyl peptides, particularly γ-EVG, are produced in yeast as products of several physiologically important reactions and are therefore natural components of yeast cells. [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]

The article presents a study which analyzes a combination of flow cytometry (FCM) and traditional screening with the use of chemicals to isolate the glutathione (GHS)-producing yeast mutants. The study employs mutagenesis, labeling of cellular GSH with 5-chloromethylfluorescein diecetate (CMFDA), and measurement of cellular GSH content. Results reveal that a combination of FCM and traditional screening with the use of chemicals are efficient for isolating GSH-producing yeast strains.

This study investigated the impact of high-speed rail (HSR) on social equity, utilizing information from a stated preference survey conducted in Vietnam. Social equity was examined across the population of four cities representing the northern, central, and southern areas of Vietnam. In general, the high price of HSR is one of the barriers to using HSR over inter-city buses and conventional trains. Low-income groups (less than VND 6 million per month) have 4.894 and 4.725 times the likelihoods, compared to higher income groups, of retaining the use of an inter-city bus or conventional train, respectively, after introducing HSR. Our findings reveal the fact that social inequity may occur, with the low-income group being especially vulnerable, due to the existence of HSR in the future. Furthermore, our results indicate that the interest of people towards inter-city buses and conventional trains varied among the four cities before and after the presence of HSR. More specifically, low-income groups in Vinh and Nha Trang were observed to have a higher feeling of staying away from HSR, as they prefer to use inter-city buses. The findings of this study suggest that planners and policymakers need to consider various components of HSR ticket planning, in order to achieve sustainable evolution of the passenger rail system. [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]