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Plant natural products (PNPs) exhibit a wide range of biological activities and have essential applications in various fields such as medicine, agriculture, and flavors. Given their natural limitations, the production of highvalue PNPs using microbial cell factories has become an effective alternative in recent years. However, host metabolic burden caused by its massive accumulation has become one of the main challenges for efficient PNP production. Therefore, it is necessary to strengthen the transmembrane transport process of PNPs. This review introduces the discovery and mining of PNP transporters to directly mediate PNP transmembrane transportation both intracellularly and extracellularly. In addition to transporter engineering, this review also summarizes several auxiliary strategies (such as small molecules, environmental changes, and vesicles assisted transport) for strengthening PNP transportation. Finally, this review is concluded with the applications and future perspectives of transportation engineering in the construction and optimization of PNP microbial cell factories. [ABSTRACT FROM AUTHOR]

Numerous applications in civil and transportation engineering require concrete with high early strength and good durability properties. Limited studies have revised the performance of high early-strength concrete prepared with calcium sulfoaluminate (CSA) cement and internal curing technology. This study evaluates the strength and durability properties of four concrete mixtures designed with low and high cement contents, incorporated with and without internal curing. Compressive and split tensile strength, autogenous and drying shrinkage, and freezing and thawing resistance were evaluated. High early-strength concrete mixtures with internal curing achieved lower strength and improved durability (shrinkage and freezing and thawing resistance) in comparison with their analogous control mixtures. All concrete mixtures obtained compressive strength higher than 17 MPa (2,500 psi) within the first 4 h. Concrete mixtures with high cement content showed less contraction (<200 με) than their analogous control mixtures. The internally cured concrete mixture with low cement content exhibited slight expansion instead of shrinkage. Finally, the freezing and thawing resistance showed great improvement because no or little damage was observed in the internally cured concrete mixtures. The internally cured concrete specimens overcame 300 cycles, whereas the control mixtures reached maximum 164 cycles. The internally cured mixtures with low and high cement contents showed a final relative dynamic of elasticity of 79.7% and 99%, respectively. Based on these results, using CSA concrete for repair works could be feasible with internal curing technique. Practical Applications: Extensive damage is observed in concrete pavements due to several factors, primarily due to freeze–thaw action and shrinkage. Given that replacing the damaged pavement is expensive and time-consuming, several transportation agencies prefer to restore/repair the degraded portion of pavement using high early-strength concrete. Using high early-strength concrete ensures the pavement achieves its design strength at an early age, which ultimately allows opening the roadway to oncoming traffic in a shorter duration. The use of calcium sulfoaluminate cement instead of ordinary portland cement in high early-strength concrete helps to reduce the overall carbon footprint due to lower energy consumed during calcium sulfoaluminate's clinkering process, along with relatively faster strength development. Previously, researchers have demonstrated the effectiveness of internal curing to improve durability of high early-strength concrete by better freeze–thaw and shrinkage resistance. Overall, the given study focuses on understanding the benefits of internal curing in high early-strength concrete mixtures prepared with a low and high calcium sulfoaluminate cement content. Irrespective of the cement content, high early-strength concrete mixtures with internal curing had superior freeze–thaw and shrinkage resistance, proving that internal curing effectively improves the durability properties without compromising on its design strength. [ABSTRACT FROM AUTHOR]

The resilience of public transit systems has become a critical issue due to their essential role in urban mobility. However, the challenges of repair selection and sequencing in integrated public transportation networks (IPTN) have not been fully explored. Therefore, we propose a bi-level resilience-based repair strategy optimisation (RRSO) model to investigate the optimisation of resilience in IPTN. To consider trip selection and account for cascade failure processes, a lower-level traffic assignment model was integrated into a single-layer RRSO model. In the traffic assignment model, perceived travel time reflects the traffic impedance of public transportation. Additionally, to assess the performance of the RRSO model under emergency repair conditions, random variables were introduced to represent uncertain factors in the traffic environment. Finally, the results demonstrate that the RRSO model outperforms standard empirical repair strategies. This study provides theoretical insights into the management of urban public transportation. [ABSTRACT FROM AUTHOR]

Effective estimation and prediction of freeway congestion propagation is the basis for formulating a traffic management strategy. A new estimation and prediction model for congestion propagation based on coordinated vehicle positioning data collected from fixed detectors is proposed. A shockwave-based method is established to model the propagation trajectory of congestion in time and space using data filtered by the Savitzy-Golay. Bayesian ridge regression is applied to determine the probability range of the propagation path of the congestion. The proposed method was tested with Wi-Fi positioning data from a section of the Beijing-Kunming Freeway in China. The results of our method were compared with filed traffic conditions estimated by loop data. The results show a difference of approximately 200s between the start time of the estimated congestion and the observed time on the selected road section. The predicted congestion start time differs from the observed results by around 100s. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of integrating Hyperloop technology with hydrogen fuel systems. The primary objective was to evaluate how Hyperloop infrastructure can incorporate hydrogen refueling stations to optimize transport efficiency and sustainability. The research utilized simulation models developed with ArchiCAD and FlexSim software to analyze the integration of Hyperloop cargo and passenger transport with hydrogen refueling processes. The study included detailed simulations of Hyperloop operations and refueling logistics, focusing on safety, efficiency, and the potential for reducing carbon emissions. Key parameters such as capsule speed, refueling times, and infrastructure requirements were analyzed. Results indicated that Hyperloop technology can significantly enhance transport efficiency, particularly for high-value and time-sensitive goods, while hydrogen refueling stations offer a sustainable energy solution with considerable potential for reducing environmental impact. The findings demonstrate that integrating hydrogen refueling stations into the Hyperloop system can improve operational efficiency and sustainability. However, challenges remain in optimizing refueling processes and infrastructure development. Future research should address these challenges and explore additional AI-based optimization techniques to enhance the overall system performance. This research is especially useful for urban planners, transportation engineers, and policymakers aiming to develop efficient, sustainable transportation systems that incorporate cutting-edge technology like Hyperloop and hydrogen refueling infrastructure. [ABSTRACT FROM AUTHOR]

A before and after study framework measures the outcomes in a group of participants before introducing an intervention, and then again afterward. In this study, a before and after study framework is adopted to evaluate the effectiveness of transportation policies and emerging technologies. Generally, the outcome of every before and after study will help decision-makers to monitor and understand the effects of interventions and to make sound decisions. However, many factors such as seasonal factors, holidays, and lane closures might interfere with the evaluation process by inducing variation in traffic volume during the before and after periods. In practice, limited effort has been made to eliminate the effects of these factors. In this study, an extreme gradient boosting (XGBoost)-based propensity score matching (PSM) method is proposed to reduce the biases caused by traffic volume variation during the before and after periods. In order to evaluate the effectiveness of the proposed method, a corridor in the City of Chandler, Arizona where an advanced traffic signal control system has been recently implemented was selected. The results indicated that the proposed method can effectively eliminate the variation in traffic volume caused by the COVID-19 during the evaluation process. In addition, the results of the t-test and Kolmogorov-Smirnov (KS) test demonstrated that the proposed method outperforms other state-of-the-art PSM methods. The application of the proposed method is also transferrable to other before and after evaluation studies and can significantly assist transportation engineers to eliminate the impacts of traffic volume variation on the evaluation process. [ABSTRACT FROM AUTHOR]

Preparing the Manual on Uniform Traffic Control Devices (MUTCD) involves gathering inputs from various public and the National Committee on Uniform Traffic Control Devices (NCUTCD) sponsoring agencies. The NCUTCD assists in developing standards, guidelines, and warrants for traffic control devices and practices employed to regulate, warn, and guide traffic flow on roadways. This organization advises the Federal Highway Administration (FHWA) and other relevant agencies on suggested updates and interpretations to the MUTCD and other nationally recognized standards. Examples of such sponsoring agencies include AASHTO, ASCE, Institute of Transportation Engineers (ITE), American Highway Users Alliance (AHUA), National Association of City Transportation Officials (NACTO), National Association of County Engineers (NACE), International Bridge, Tunnel and Turnpike Association (IBTTA), and American Traffic Safety Services Association (ATSSA). Other national and regional agencies have also been invited to provide feedback on the draft manual. Although all comments are considered valuable, those from federal agencies may hold more weight due to their expertise in specific subject matters. This study utilized text-mining techniques to analyze the comments from the sponsoring agencies, aiming to identify commonalities and distinct features in their feedback. The main question addressed was whether each agency effectively represented its interests and if there were shared interests among them. The study also explored the suggestions, questions, and recommendations raised by each agency. The findings revealed that some concerns were shared among agencies, although in most cases, they represented individual interests. Specifically, some agencies shared a common interest in speed limits, whereas others had similar topics concerning signs and markings. Other shared interests are bike lanes, 85th percentile speed, and pedestrian- and bus lane–related topics. This study's insights into the interests and concerns of various MUTCD sponsoring agencies can aid in creating more effective, engaging, collaborative, and well-rounded technical documents. As a limitation, this study only used the current MUTCD revision comments, and hence the results reflect only recent concerns from the agencies. Practical Applications: The Federal Highway Administration collects comments from both the general public and NCUTCD sponsoring agencies for modifying the MUTCD. This study used the comments from the NCUTCD sponsoring agencies submitted by May 2021 and conducted supervised and unsupervised text mining analysis to understand any available patterns, differences, or commonalities in the agencies' concerns in shaping the MUTCD. The findings indicate the presence of various shared interests among the agencies and some specific features that were specific to the agencies. In addition, it was observed that the majority of the agencies have a great concern for the safety and well-being of society by showing a common interest in safety influencing factors such as speed, road signs, and the definition and use of the 85th percentile speed. This understanding can foster greater collaboration among the agencies, leading to more well-rounded and comprehensive guidelines. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)