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Urban air mobility (UAM) has the potential to revolutionize transportation in metropolitan areas, providing a new mode of transportation that could alleviate congestion and improve accessibility. However, the integration of UAM into existing transportation systems is a complex task that requires a thorough understanding of its impact on traffic flow and capacity. In this paper, we conduct a survey to investigate the current state of research on UAM in metropolitan-scale traffic using simulation techniques. We identify key challenges and opportunities for the integration of UAM into urban transportation systems, including impacts on existing traffic patterns and congestion; safety analysis and risk assessment; potential economic and environmental benefits; and the development of shared infrastructure and routes for UAM and ground-based transportation. We also discuss the potential benefits of UAM, such as reduced travel times and improved accessibility for underserved areas. Our survey provides a comprehensive overview of the current state of research on UAM in metropolitan-scale traffic using simulation and highlights key areas for future research and development., Comment: I found significant inaccuracies that greatly affect its findings. To maintain scientific integrity and prevent misleading readers, I request its withdrawal. Once corrected, I plan to resubmit the revised paper to arXiv. I appreciate your understanding

Additional file 1: Fig. S1. Directed acyclic graph. Fig. S2. Pearson’s correlation matrix. Fig. S3. Weighted values of urinary metals for OA in WQS models. Fig. S4. Associations of the urinary metals with OA risk estimated by Bayesian Kernel Machine Regression (BKMR). Table S1. Distributions of metals in the study population. Table S2. OR (95% CI) in OA associated with single and mixed urinary metals levels with further adjustment for occupation. Table S3. OR (95% CI) in OA associated with single and mixed urinary metals levels with further adjustment for other diseases and medicine use. Table S4. OR (95% CI) in OA associated with single and mixed urinary metals levels with further adjustment for survey cycle. Table S5. OR (95% CI) in OA associated with single and mixed urinary metals levels after excluding participants with abnormal urinary creatinine. Table S6. OR (95% CI) in OA associated with single and mixed urinary metals levels after excluding pregnant participants. Table S7. Biological aging markers as mediators in the associations of single metals with OA risk. Table S8. Telomere length and biological age/biological age as serial mediators in the associations of single metals with OA risk.

Additional file 2. Code for analyses.

As the shared micromobility becomes a part of our daily life and environment, we expect the number of low-speed modes for first-and-last mile trips to grow rapidly. The shared micomobility is expected to serve billions of humans, bringing us considerable advantages. With this growth, shared micromobility simulation such as docked stations based shared bikes, dockless shared bikes and e-scooters, are regarded as promising solutions to deal with a large number of first-and-last mile trips. In this paper, we first provide a comprehensive overview of shared micromobility simulation and its related validation metrics. Next, we classify the research topics of shared micromobility simulation, summarize, and classify the existing works. Finally, challenges and future directions are provided for further research.

A solid-phase preparation method was applied to obtain a novel, green and effective functional nanoparticle, silica-supported sulfur monochloride (silica-s-S2Cl2), by the chemical reaction between chlorine atom and silicon hydroxyl on the silica surface. Through this chemical reaction, silica surface supported with high content of sulfur, and the functional nanoparticles can not only vulcanize the rubber instead of sulfur or other vulcanizing agent with high performance, but also improve the filler-rubber interaction as a modifier due to the improved modification effect. 29Si NMR, Raman spectroscopy, Element analysis and TGA confirm that the sulfur monochloride is chemically bonded on the silica surface. Cure properties measurement, morphology of filler dispersion, mechanical properties measurement, immobilized polymer layer and oxidation induction time increment together show that the novel vulcanizing agent silica-s-S2Cl2 instead of sulfur in rubber vulcanization gives rise to significant improvement in the crosslinking density and the interfacial adhesion between silica particles and the rubber matrix, which is on account of the promoted vulcanizing on the functional silica nanoparticles surface with the supported sulfur.

A high reactive sulfocompound, sulfur monochloride, was chemically supported onto the surface of silica (silica-s-S2Cl2) by the reaction between chloric atom and silanol hydroxyl to obtain a novel vulcanizing agent, silica supported sulfur monochloride (silica-s-S2Cl2). Silica-s-S2Cl2 can be homogeneously dispersed in SBR matrix as a modifier and cure the styrene-butadiene rubber (SBR) without sulfur as a novel high-efficiency vulcanizing agent. The sulfur and Bis[3-(triethoxysilyl)propyl] Tetrasulfide (TESPT) silane coupling agent vulcanized SBR composites were mainly polysulfide crosslinks, on the contrary, the vulcanization by silica-s-S2Cl2 give priority to the mono- and disulfides crosslinks. The highlight of this work lies in the fact that apparent improvement has been achieved by novel and high efficient functional particles due to the silica surface supported with sulfur monochloride, which may open up new opportunities for the preparation of functional nano-fillers in rubber industry.

Sorbus alnifolia (Siebold &amp, Zucc.) K.Koch (Rosaceae) is an economically important tree in the temperate forests of Eastern China. In recent decades, ever-increasing use and modification of forestlands have resulted in major degeneration of the natural habitat of S. alnifolia. Moreover, S. alnifolia seeds germinate in a complicated way, leading to a high cost of propagation. The current study aimed to determine the requirements for breaking seed dormancy and for germination as well as to characterize the type of seed dormancy present in this species. Moreover, the roles of temperature, cold/warm stratification, and gibberellic acid (GA3) in breaking dormancy were tested combined with a study of the soil seed bank. The results showed that intact seeds of S. alnifolia were dormant, requiring 150 days of cold stratification to achieve the maximum germination percentage at 5/15 &deg, C. Exposure of the seeds to ranges of temperatures at 15/25 &deg, C and 20/30 &deg, C resulted in secondary dormancy. Scarifying seed coat and partial removal of the cotyledon promoted germination. Compared with long-term cold stratification, one month of warm stratification plus cold stratification was superior in breaking dormancy. Application of GA3 did not break the dormancy during two months of incubation. Seeds of S. alnifolia formed a transient seed bank. The viability of freshly matured S. alnifolia seeds was 87.65% &plusmn, 11.67%, but this declined to 38.25% after 6-months of storage at room temperature. Seeds of S. alnifolia have a deep physiological dormancy, cold stratification will be useful in propagating this species. The long chilling requirements of S. alnifolia seeds would avoid seedling death in winter.