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Stroke classification for online handwriting and sketches, aimed at grouping strokes into different semantic categories, has drawn considerable attention due to its wide applications. This task is challenging since individual strokes look similar and are easily confused with each other. The key is to consider both the individual strokes and the contextual information jointly for making prediction. Previous methods are insufficient in modeling and exploiting complex contextual information of strokes. To overcome this limitation, we propose a Transformer-based model for Online Handwriting and Sketches (T-OHS), with novel relation encoding schemes to take advantage of temporal and spatial information in stroke sequence. Particularly, we introduce a coarse-to-fine hierarchical encoding approach based on the polar coordinate system for precisely modeling spatial relations between strokes. Experiments on three types of handwriting data, including online handwritten documents, diagrams, and sketches, demonstrate that our method is universal and provides state-of-the-art performance. • We propose a novel stroke classification method for online handwriting and sketches. • We design an effective encoding scheme to represent the spatial relations among strokes. • Extensive experiments demonstrate that our method is universal and provides the SOTA performance. [ABSTRACT FROM AUTHOR]

Polarization and phase manipulations have gained widespread applications across various fields. The emergence of metasurface provides a new platform for the manipulation of electromagnetic waves. However, most metasurfaces are limited to modulating only one single property. Here, a coding metasurface that achieves 1‐bit phase manipulations of both co‐polarized and cross‐polarized reflected waves for linear and circular polarization wave excitations. Notably, the proposed metasurface enables co‐polarized 1‐bit phase responses for incident electric fields with arbitrary orientations and spin directions. The simulated results demonstrate an operating efficiency over −1.7 dB in the frequency range from 7 to 11.1 GHz, with a relative bandwidth of 45.3%. Furthermore, the introduction of space‐polarization coding strategies facilitates the beam and polarization manipulations. To verify the feasibility of the coding metasurface, a sample and conduct experiments are fabricated, revealing good agreement between the simulations and measurements. These findings hold significant promise for the advancement of radar, imaging, and wireless communication systems, with potential applications in various domains. [ABSTRACT FROM AUTHOR]

Objectives: The treatment of refractory and recurrent acute myeloid leukaemia (AML) is still a challenge with poor response rates and short survival times. In an attempt to solve this problem, we constructed a tandem bispecific chimeric antigen receptor (CAR) targeting CD123 and C‐type lectin‐like molecule 1 (CLL‐1), two different AML antigens, and verified its cytotoxic effects in vitro. Methods: We established and cultured K562 cell lines expressing both CD123 and CLL1 antigens. Single‐target CAR‐T cells specific to CD123 and CLL1 were engineered, alongside tandem CD123/CLL1 bispecific CAR‐T cells. Flow cytometry was used to determine cell phenotypes, transfection efficiencies, cytokine release, and CAR‐T‐cell proliferation, and an lactate dehydrogenase assay was used to detect the cytotoxicity of CD123/CLL‐1 bispecific tandem CAR‐T cells in vitro. Results: Two types of tandem CAR‐T cells exhibited significant killing effects on CLL‐1 + CD123+ leukaemia cell lines and primary AML tumour cells. The killing efficiency of tandem CAR‐T cells in the case of single antigen expression is comparable to that of single target CAR‐T cells. When faced with dual target tumour cells, dual target CAR‐T cells significantly surpass single target CAR‐T cells. CD123/CLL‐1 CAR‐T cells in tandem targeted and killed CD123‐ and CLL‐1‐positive leukaemia cell lines and released a large number of cytokines. Conclusions: CD123/CLL‐1 CAR‐T cells in tandem can simultaneously target CD123 and CLL‐1 on AML cells, demonstrating a significant ability to kill single antigens and multi‐target tumour cells. This suggests that CD123/CLL‐1 CAR‐T cells exhibit significant advantages in the expression of multiple antigens in a wide range of target cells, which may help overcome the challenges posed by tumour heterogeneity and evasion mechanisms. [ABSTRACT FROM AUTHOR]