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Taxis provide a type of on-demand mobility service in urban transportation. There are growing concerns regarding the level of service of taxis in satisfying residents' mobility demand. However, the mismatch between demand and supply of taxi services has not been resolved even with the introduction of app-based vehicle services. In this study, three indicators are constructed using the Shanghai taxi global positioning system (GPS) dataset to reveal the spatial–temporal mismatch pattern. The issue is further analyzed via a case study, in which seven regions with frequent mismatch patterns are identified in the time period from 21:00 to 22:00. Then, a multinomial logistic regression model is employed to identify the demographic and built-environment factors contributing to the taxi mismatch problem. The study results show that population density, residential areas, the number of points of interest, and road density have significant relationships with the taxi undersupply. In contrast, the areas of commercial lands, as well as the other two transportation-related factors, that is, the number of bus stops and the distance to nearest subway station, are observed to be statistically significant for both "oversupply" and "undersupply" conditions. This study provides valuable insights for identifying mismatch patterns and interpreting the mismatch problem as a function of spatially explicit factors that are of great use for urban governance, especially in the improvement of taxi efficiency, taxi management, and urban planning. [ABSTRACT FROM AUTHOR]

The constitutive model and modulus parameter equivalence of shape memory alloy composites (SMAC) serve as the foundation for the structural dynamic modeling of composite materials, which has a direct impact on the dynamic characteristics and modeling accuracy of SMAC. This article proposes a homogenization method for SMA composites considering interfacial phases, models the interface stress transfer of three-phase cylinders physically, and derives the axial and shear stresses of SMA fiber phase, interfacial phase, and matrix phase mathematically. The homogenization method and stress expression were then used to determine the macroscopic effective modulus of SMAC as well as the stress characteristics of the fiber phase and interface phase of SMA. The findings demonstrate the significance of volume fraction and tensile pre-strain in stress transfer between the fiber phase and interface phase at high temperatures. The maximum axial stress in the fiber phase is 705.05 MPa when the SMA is fully austenitic and the pre-strain increases to 5%. At 10% volume fraction of SMA, the fiber phase's maximum axial stress can reach 1000 MPa. Ultimately, an experimental verification of the theoretical calculation method's accuracy for the effective modulus of SMAC lays the groundwork for the dynamic modeling of SMAC structures., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Huang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Singlet oxygen ( 1 O 2 ) is a highly effective reactive species in selectively oxidizing organic pollutants. However, it is still challenging to rationally design robust catalysts for the selective generation of 1 O 2 . Herein, the coordination and engineering architecture of the foam board-like CoSe 2 alloy were facilely constructed through a green solvent-free method and displayed almost 100% 1 O 2 production selectivity. The CoSe 2 alloy showed excellent catalytic ability for the efficient and fast removal of organic pollutants via peroxymonosulfate (PMS) activation compared with previously reported cobalt-based catalysts. The CoSe 2 /PMS system exhibited strong resistance for a broad pH range (3.0-11.0) and various coexisting inorganic ions owing to the advantage of the strong bonding of Co-Se in CoSe 2 alloy. Mechanism studies revealed that 1 O 2 was the only reactive oxygen species in the CoSe 2 /PMS system. Theoretical calculations demonstrated that Co was the dominant adsorption site for PMS in CoSe 2 , and the production pathway of 1 O 2 was PMS* → *OH → *O → 1 O 2 . In addition, it was proved that *OH and *O served as the rate-determining steps for the formation of 1 O 2 by PMS activation on CoSe 2 alloy. These findings provide a rational strategy for preparing a series of low-cost transition metal-based alloy catalysts for PMS activation to achieve high-efficiency 1 O 2 production in the elimination of organic pollutants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A suitable environment is essential for successful long-term cell culturing in vitro. Too high or too low temperature will affect the growth of cells, so we need to maintain the constant temperature of the cell culture environment. Usually, cells are cultured in a cell incubator, and the constant temperature is provided by the cell incubator. Recently, we have developed a multi-channel axon stretch growth bioreactor for rapid acquisition of autologous nerve tissue. Since the motor and controller are placed in the incubator for a long time, the service life of the equipment will be shortened or even damaged due to high humidity and weak acid environment. In order to enable the axon stretch growth bioreactor to culture cells independently, we designed a constant temperature control system for the device. Firstly, the simulation results show that the fuzzy PID control reduces the overshoot and improves the traditional PID control with large overshoot and low control precision. Then, the two control algorithms were applied to the multi-channel axon stretch growth bioreactor by STM32F4 microcontroller. The experimental data show that the fuzzy PID control algorithm has good control effect and can meet the requirement of constant temperature of cell growth. Finally, nerve cells derived from human pluripotent stem cells were successfully cultured in a cell culture amplification chamber under a constant temperature environment provided by a fuzzy PID controller, and well-developed axons could be seen. In the future, we may transplant stretch growth axons into living organisms to repair nerve damage., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Herein, we develop a novel strategy for preparing all-inorganic cesium lead halide (CsPbX 3 , X = Cl, Br, I) perovskite nanocrystals (NCs)@Zn-based metal-organic framework (MOF) composites through interfacial synthesis. The successful embedding of fluorescent perovskite NCs in Zn-MOFs is due to the in situ confined growth, which is attributed to the re-nucleation of water-triggered phase transformation from Cs 4 PbBr 6 to CsPbBr 3 . The controllable synthesis of mixed-halide based composites with various emission wavelength can be achieved by adding the desired amount of halide (Cl or I) salts in the re-nucleation process. More importantly, the anion exchange reaction is inhibited among various composites with different halogen atoms by being trapped in MOFs. Besides, a white light-emitting diode (WLED) is produced using a blue LED chip with the green-emitting and red-emitting composites, which has a color coordinate of (0.3291, 0.3272) and a wide color gamut. This work provides a novel route to achieving perovskite NCs growth in MOFs, which also can be extended to the other NCs embedded in frames as well., (© 2022 IOP Publishing Ltd.)