The Review of Recent Trend for School Bus Routing Problem

The School Bus Routing Problem (SBRP) is a complex transportation challenge involving finding optimal bus routes. This review paper provides an overview of the recent developments in SBRP research and focuses on three sub-problems: Bus Route Generation, Bus Route Scheduling, and Bus Stop Selection. The paper examines recent publications from 57 relevant articles. It highlights the increasing focus on real-world and complex scenarios, as well as the growing popularity of metaheuristic approaches in addressing SBRP challenges. The analysis reveals the significance of bus route generation, bus route scheduling, and bus stop selection, showcasing the effectiveness of machine learning and heuristic or metaheuristic algorithms in improving route quality. This study also classifies SBRP problems based on the number of schools, service surroundings (urban or rural), mixed-load scenarios, and fleet mix (homogeneous or heterogeneous). Finally, the paper explores the objectives of SBRP research, including minimising the total cost, distance, time, and number of buses. Meanwhile, the constraints of this study are the capacity of a bus, the maximum riding time, time windows, the maximum walking time between two stops and so on. This comprehensive review paper aims to offer a framework for new researchers and provides valuable insights for future research directions in this transportation area

Quartz Crystal Microbalance with Dissipation Monitoring of Dynamic Viscoelastic Changes of Tobacco BY-2 Cells under Different Osmotic Conditions

The plant cell mechanics, including turgor pressure and wall mechanical properties, not only determine the growth of plant cells, but also reflect the functional and structural changes of plant cells under biotic and abiotic stresses. However, there are currently no appropriate techniques allowing to monitor the complex mechanical properties of living plant cells non-invasively and continuously. In this work, quartz crystal microbalance with dissipation (QCM-D) monitoring technique with overtones (3–9) was used for the dynamic monitoring of adhesions of living tobacco BY-2 cells onto positively charged N,N-dimethyl-N-propenyl-2-propen-1-aminiumchloride homopolymer (PDADMAC)/SiO2 QCM crystals under different concentrations of mannitol (CM) and the subsequent effects of osmotic stresses. The cell viscoelastic index (CVIn) (CVIn = ΔD⋅n/ΔF) was used to characterize the viscoelastic properties of BY-2 cells under different osmotic conditions. Our results indicated that lower overtones of QCM could detect both the cell wall and cytoskeleton structures allowing the detection of plasmolysis phenomena; whereas higher overtones could only detect the cell wall’s mechanical properties. The QCM results were further discussed with the morphological changes of the BY-2 cells by an optical microscopy. The dynamic changes of cell’s generated forces or cellular structures of plant cells caused by external stimuli (or stresses) can be traced by non-destructive and dynamic monitoring of cells’ viscoelasticity, which provides a new way for the characterization and study of plant cells. QCM-D could map viscoelastic properties of different cellular structures in living cells and could be used as a new tool to test the mechanical properties of plant cells

Comparing the Mechanical Properties of Rice Cells and Protoplasts under PEG6000 Drought Stress Using Double Resonator Piezoelectric Cytometry

Plant cells’ ability to withstand abiotic stress is strongly linked to modifications in their mechanical characteristics. Nevertheless, the lack of a workable method for consistently tracking plant cells’ mechanical properties severely restricts our comprehension of the mechanical alterations in plant cells under stress. In this study, we used the Double Resonator Piezoelectric Cytometry (DRPC) method to dynamically and non-invasively track changes in the surface stress (ΔS) generated and viscoelasticity (storage modulus G′ and loss modulus G″) of protoplasts and suspension cells of rice under a drought stress of 5–25% PEG6000. The findings demonstrate that rice suspension cells and protoplasts react mechanically differently to 5–15% PEG6000 stress, implying distinct resistance mechanisms. However, neither of them can withstand 25% PEG6000 stress; they respond mechanically similarly to 25% PEG6000 stress. The results of DRPC are further corroborated by the morphological alterations of rice cells and protoplasts observed under an optical microscope. To sum up, the DRPC technique functions as a precise cellular mechanical sensor and offers novel research tools for the evaluation of plant cell adversity and differentiating between the mechanical reactions of cells and protoplasts under abiotic stress

The Review of Recent Trend for School Bus Routing Problem

The School Bus Routing Problem (SBRP) is a complex transportation challenge involving finding optimal bus routes. This review paper provides an overview of the recent developments in SBRP research and focuses on three sub-problems: Bus Route Generation, Bus Route Scheduling, and Bus Stop Selection. The paper examines recent publications from 57 relevant articles. It highlights the increasing focus on real-world and complex scenarios, as well as the growing popularity of metaheuristic approaches in addressing SBRP challenges. The analysis reveals the significance of bus route generation, bus route scheduling, and bus stop selection, showcasing the effectiveness of machine learning and heuristic or metaheuristic algorithms in improving route quality. This study also classifies SBRP problems based on the number of schools, service surroundings (urban or rural), mixed-load scenarios, and fleet mix (homogeneous or heterogeneous). Finally, the paper explores the objectives of SBRP research, including minimising the total cost, distance, time, and number of buses. Meanwhile, the constraints of this study are the capacity of a bus, the maximum riding time, time windows, the maximum walking time between two stops and so on. This comprehensive review paper aims to offer a framework for new researchers and provides valuable insights for future research directions in this transportation area

Enhanced Cathodic Preconcentration of As(0) at Au and Pt Electrodes for Anodic Stripping Voltammetry Analysis of As(III) and As(V)

We report that the cathodic preconcentration of electron-insulating As(0) on Au and Pt electrodes can be enhanced by chemical reduction of As­(III) and As­(V) by electrogenerated H₂, as studied by cyclic voltammetry. This finding is used for sensitive anodic stripping voltammetry (ASV) analysis of As­(III) and/or As­(V) at the Au electrode. About three As(0) monolayers were cathodically preconcentrated on the Pt electrode at −0.3 V (vs SCE) in 0.5 M aqueous H₂SO₄, as a result of both the chemical reduction of the solution-state As­(III) near the electrode surface by the electrogenerated H₂ and the direct electroreduction of As­(III) on the highly catalytic surface Pt sites. Only one As(0) monolayer was electrodeposited at −0.2 V (vs SCE) on the Au electrode in 0.5 M aqueous H₂SO₄, but about two As(0) monolayers were deposited on the Au electrode at a more negative potential at which the mild evolution of H₂ occurred. The electrogenerated H₂ could also chemically reduce As­(V), though the direct electroreduction of As­(V) was sluggish on the Au electrode. Linear sweep ASV (LSASV) oxidation of the preconcentrated As(0) to As­(III) and then to As­(V) at a fast scan rate gave two sharper and higher anodic peaks on the Au electrode than on the Pt electrode. On the basis of these observations, sensitive dual-signal LSASV analysis of As­(III) and/or As­(V) was achieved on the Au electrode, with limits of detection of 1.0 nM for As­(III) and 5.4 nM for As­(V) under optimized experimental conditions. Our method was successfully applied for analysis of As­(III) and/or As­(V) in real water samples. The insights into cathodic As(0) deposition provided here may help the better understanding of electrochemical deposition of many other electron-insulating thin films, especially those obeying the electrode material-dependent inner-sphere mechanism, for electrochemical and surface-coating applications

Real‐Time Quantification of Cell Mechanics and Functions by Double Resonator Piezoelectric Cytometry – Theory and Study of Cellular Adhesion of HUVECs

Abstract Cell mechanics is closely associated with cellular structure and function. However, the inability to measure both cellular force and viscoelasticity of statistically significant number of cells noninvasively remains a challenge for quantitative characterizations of various cellular functions and practical applications. Here a double resonator piezoelectric cytometry (DRPC), using AT and BT cut quartz crystals of the same frequency and surface morphology is developed to simultaneously quantify the cells‐generated forces (ΔS) and viscoelastic moduli (G′, G″) of a population of isolated single cells or cells with different degrees of cell‐cell interactions in a non‐invasive and real time manner. DRPC captures the dynamic mechanical parameters ΔS and G′, G″ during the adhesions of human umbilical vein endothelial cells (HUVECs) under different ligand densities of adhesion molecules fibronectin or Arg‐Gly‐Asp (RGD) modified on the gold surfaces of 9 MHz AT and BT cut quartz crystals, and different seeding densities of HUVECs. It is found that both the ligand density and cell seeding density affect the magnitudes of ΔS and G′, G″ and their correlations are revealed for the first time by DRPC. The validity of DRPC is further verified by mechanical changes of the cells in response to treatments with cytoskeleton regulators