Transfusor: Transformer Diffusor for Controllable Human-like Generation of Vehicle Lane Changing Trajectories

With ongoing development of autonomous driving systems and increasing desire for deployment, researchers continue to seek reliable approaches for ADS systems. The virtual simulation test (VST) has become a prominent approach for testing autonomous driving systems (ADS) and advanced driver assistance systems (ADAS) due to its advantages of fast execution, low cost, and high repeatability. However, the success of these simulation-based experiments heavily relies on the realism of the testing scenarios. It is needed to create more flexible and high-fidelity testing scenarios in VST in order to increase the safety and reliabilityof ADS and ADAS.To address this challenge, this paper introduces the "Transfusor" model, which leverages the transformer and diffusor models (two cutting-edge deep learning generative technologies). The primary objective of the Transfusor model is to generate highly realistic and controllable human-like lane-changing trajectories in highway scenarios. Extensive experiments were carried out, and the results demonstrate that the proposed model effectively learns the spatiotemporal characteristics of humans' lane-changing behaviors and successfully generates trajectories that closely mimic real-world human driving. As such, the proposed model can play a critical role of creating more flexible and high-fidelity testing scenarios in the VST, ultimately leading to safer and more reliable ADS and ADAS.Comment: Submitted for presentation only at the 2024 Annual Meeting of the Transportation Research Boar

Evaluation volatile flavor compounds during storage time in bacon made by different pig breeds

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Lgr5+CD44+EpCAM+ Strictly Defines Cancer Stem Cells in Human Colorectal Cancer

Background/Aims: Although EpCAM+CD44+ cells exhibit more stem-like properties than did EpCAM-CD44- cells, the specificity of EpCAM combined with CD44 in defining CSCs needs further improvement. Lgr5 is used as a biomarker to isolate cancer stem cells (CSCs) in colorectal cancer. However, it remains unclear whether Lgr5, along with EpCAM and CD44, can further identify and define CSCs in colorectal cancer. Methods: Lgr5+CD44+EpCAM+, Lgr5+CD44+EpCAM-, Lgr5+CD44-EpCAM+, Lgr5-CD44+EpCAM+, and Lgr5-CD44-EpCAM-cells were separately isolated using fluorescence-activated cell sorting (FACS). Colony formation, self-renewal, differentiation, and tumorigenic properties of these cells were investigated through in vitro experiments and in vivo tumor xenograft models. The expression of stemness genes and CSC- and epithelial-mesenchymal transition (EMT)-related genes, such as KLF4, Oct4, Sox2, Nanog, CD133, CD44, CD166, ALDH1, Lgr5, E-cadherin, ZO-1, Vimentin, Snail, Slug, and Twist, was examined using real-time PCR. Results: Lgr5-positive subpopulations exhibited higher capacities for colony formation, self-renewal, differentiation, and tumorigenicity as well as higher expression of stemness genes and mesenchymal genes and lower expression of epithelial genes than did Lgr5-negative subpopulations. Conclusion: Our data revealed that tumorigenic cells were highly restricted to Lgr5-positive subpopulations. Most importantly, Lgr5+CD44+EpCAM+ cells exhibited more pronounced CSC-like traits than did any other subpopulation, indicating that Lgr5 combined with CD44 and EpCAM can further improve the stem-like traits of CSCs in colorectal cancer