Yes-associated protein 1(YAP1)is a downstream effector of the Hippo signaling pathway,and it is involved in tumorigenesis,tissue repair,growth,and development.In this review,the biological roles and the mechanisms of ...Yes-associated protein 1(YAP1)is a downstream effector of the Hippo signaling pathway,and it is involved in tumorigenesis,tissue repair,growth,and development.In this review,the biological roles and the mechanisms of YAP1 in mediating stem cell fate decisions are discussed,including cell proliferation,differentiation,and apoptosis.In general,YAP1 promotes the proliferation and differentiation of stem cells,including embryonic stem cells and adult stem cells.It inhibits apoptosis by binding to the transcription factors,e.g.,transcriptional enhanced associate domain(TEAD),Smad,runt-related transcription factor 1/2,p73,p63,and Erb84,to maintain tissue homeostasis.The translocalization of YAP1 in cellular nuclei and the phosphorylation in the cytoplasm work as important and unusual events for the activation of YAP1.Moreover,YAP1 serves as the crosstalk for the Hippo pathway and other signaling pathways,including the Wnt and Notch pathways.It is highlighted in this review that YAP1 is an essential regulator for stem cells that have significant applications in regenerative medicine and reproductive medicine.展开更多
Background With the rapid development of Web3D, virtual reality, and digital twins, virtual trajectories and decision data considerably rely on the analysis and understanding of real video data, particularly in emerge...Background With the rapid development of Web3D, virtual reality, and digital twins, virtual trajectories and decision data considerably rely on the analysis and understanding of real video data, particularly in emergency evacuation scenarios. Correctly and effectively evacuating crowds in virtual emergency scenarios are becoming increasingly urgent. One good solution is to extract pedestrian trajectories from videos of emergency situations using a multi-target tracking algorithm and use them to define evacuation procedures. Methods To implement this solution, a trajectory extraction and optimization framework based on multi-target tracking is developed in this study. First, a multi-target tracking algorithm is used to extract and preprocess the trajectory data of the crowd in a video. Then, the trajectory is optimized by combining the trajectory point extraction algorithm and Savitzky-Golay smoothing filtering method. Finally, related experiments are conducted, and the results show that the proposed approach can effectively and accurately extract the trajectories of multiple target objects in real time. Results In addition, the proposed approach retains the real characteristics of the trajectories as much as possible while improving the trajectory smoothing index, which can provide data support for the analysis of pedestrian trajectory data and formulation of personnel evacuation schemes in emergency scenarios. Conclusions Further comparisons with methods used in related studies confirm the feasibility and superiority of the proposed framework.展开更多
We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transiti...We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transition of VO_2 film is induced by the Joule thermal effect of the top metal layer. The finite-integration-time-domain(FITD) method and finite element method(FEM) are used for numerical simulations. The sample is fabricated using a surface micromachining process,and characterized by a THz time-domain-spectrometer(TDS). When the bias current is 0.225 A, the intensity modulation depths at two central frequencies of 0.56 THz and 0.91 THz are about 81.7% and 81.3%, respectively. This novel design can achieve dynamically electric–thermo–optic modulation in the THz region, and has potential applications in the fields of THz communications, imaging, sensing, and astronomy exploration.展开更多
基金This work was supported by grants from the National Nature Science Foundation of China(32170862,31872845)Major Scientific and Technological Projects for Collaborative Prevention and Control of Birth Defect in Hunan Province(2019SK1012)+4 种基金Key Grant of Research and Development in Hunan Province(2020DK2002)High-Level Talent Gathering Project in Hunan Province(2018RS3066)Natural Science Foundation of Hunan Province(2020JJ5383,2021JJ40365)Health Commission Foundation of Hunan Province(202104052273,202102050927)Hunan Province College Student Research Learning and Innovative Experiment Project(S202010542084).
文摘Yes-associated protein 1(YAP1)is a downstream effector of the Hippo signaling pathway,and it is involved in tumorigenesis,tissue repair,growth,and development.In this review,the biological roles and the mechanisms of YAP1 in mediating stem cell fate decisions are discussed,including cell proliferation,differentiation,and apoptosis.In general,YAP1 promotes the proliferation and differentiation of stem cells,including embryonic stem cells and adult stem cells.It inhibits apoptosis by binding to the transcription factors,e.g.,transcriptional enhanced associate domain(TEAD),Smad,runt-related transcription factor 1/2,p73,p63,and Erb84,to maintain tissue homeostasis.The translocalization of YAP1 in cellular nuclei and the phosphorylation in the cytoplasm work as important and unusual events for the activation of YAP1.Moreover,YAP1 serves as the crosstalk for the Hippo pathway and other signaling pathways,including the Wnt and Notch pathways.It is highlighted in this review that YAP1 is an essential regulator for stem cells that have significant applications in regenerative medicine and reproductive medicine.
文摘Background With the rapid development of Web3D, virtual reality, and digital twins, virtual trajectories and decision data considerably rely on the analysis and understanding of real video data, particularly in emergency evacuation scenarios. Correctly and effectively evacuating crowds in virtual emergency scenarios are becoming increasingly urgent. One good solution is to extract pedestrian trajectories from videos of emergency situations using a multi-target tracking algorithm and use them to define evacuation procedures. Methods To implement this solution, a trajectory extraction and optimization framework based on multi-target tracking is developed in this study. First, a multi-target tracking algorithm is used to extract and preprocess the trajectory data of the crowd in a video. Then, the trajectory is optimized by combining the trajectory point extraction algorithm and Savitzky-Golay smoothing filtering method. Finally, related experiments are conducted, and the results show that the proposed approach can effectively and accurately extract the trajectories of multiple target objects in real time. Results In addition, the proposed approach retains the real characteristics of the trajectories as much as possible while improving the trajectory smoothing index, which can provide data support for the analysis of pedestrian trajectory data and formulation of personnel evacuation schemes in emergency scenarios. Conclusions Further comparisons with methods used in related studies confirm the feasibility and superiority of the proposed framework.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11574059,61565004,and 11774288)the National Technology Major Special Project,China(Grant No.2017ZX02101007-003)+2 种基金the Natural Science Foundation of Guangxi,China(Grant Nos.2015GXNSFDA139039 and2017GXNSFBA198116)the Foundation from Guangxi Key Laboratory of Automatic Detection Technology and Instrument,China(Grant No.YQ16101)the Innovation of Guangxi Graduate Education,China(Grant Nos.2018YJCX70,2018YJCX67,and 2018YJCX74)
文摘We experimentally demonstrate an electrically triggered terahertz(THz) dual-band tunable band-pass filter based on Si_3 N_4–VO_2–Si_3 N_4 sandwich-structured hybrid metamaterials. The insulator–metal phase transition of VO_2 film is induced by the Joule thermal effect of the top metal layer. The finite-integration-time-domain(FITD) method and finite element method(FEM) are used for numerical simulations. The sample is fabricated using a surface micromachining process,and characterized by a THz time-domain-spectrometer(TDS). When the bias current is 0.225 A, the intensity modulation depths at two central frequencies of 0.56 THz and 0.91 THz are about 81.7% and 81.3%, respectively. This novel design can achieve dynamically electric–thermo–optic modulation in the THz region, and has potential applications in the fields of THz communications, imaging, sensing, and astronomy exploration.
