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In this paper, inspired by origami structures, we offer a very simple tuning method to overcome the limitations of general elastic metasurfaces, where only a certain functionality at a certain frequency range can be achieved, by designing a reflective metasurface based on foldable/deployable zig-zag structures. By utilizing peg/screw connections, the folding angles of the zig-zag structures can be easily tuned while also being fixable. By tuning the folding angle, the subunit of the zig-zag metasurface can cover a 2π phase shift span and the phase shift can be tuned continuously, and almost linearly, with respect to the folding angle. With a simple folding motion, the tunable reflective metasurface can steer reflected flexural waves in different directions and focus-reflected flexural waves with different focal distances. In addition to demonstrating tunable performance, the mechanism that associates the changing speed of the phase shift is explained. The proposed tunable zig-zag elastic metasurface provides a new way to design reconfigurable metamaterials/metasurfaces.

Electromagnetic imaging achieves enhanced resolution by leveraging the advanced sensing and data analysis capabilities of Internet of Things (IoT) systems. This paper introduces a novel learning approach for generative adversarial networks (GANs) to tackle significant challenges in electromagnetic sensing. The proposed method involves deploying additional transmitters and receivers to irradiate TM (transverse magnetic) and TE (transverse electric) polarization waves around uniaxial objects to capture the scattered field in free space. Subsequently, scattered field generative adversarial networks (SF-GANs) are utilized to simulate and learn the characteristics of Maxwell's equations. Numerical simulations and experimental results demonstrate the superior performance of the SF-GANs compared to backpropagation generative adversarial networks (BP-GANs). Furthermore, it is worth noting that our method is capable of reconstructing high-dielectric-constant objects. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of genetic polymorphism of MTHFR C677T (rs1801133) on methotrexate (MTX) related toxicity in pediatric mature B-cell lymphoma patients., Methods: Fifty-eight intermediate and high risk patients under 18 years of age with mature B-cell lymphoma who received 5 g/m 2 MTX (24 h intravenous infusion) in Sun Yat-sen University Cancer Center from August 2014 to December 2021 were included, and their toxicity of high-dose MTX (HD-MTX) were monitored and analyzed., Results: Among the 58 pediatric patients, the number of CC, CT, and TT genotypes for MTHFR C677T was 33, 19 and 6, respectively. A total of 101 courses of HD-MTX therapy were counted, of which plasma MTX level >0.2 μmol/L at 48 h post-MTX infusion were observed in 35 courses, ≤0.2 μmol/L in 66 courses. Inter-group comparison showed that plasma MTX level >0.2 μmol/L at 48 h post-MTX infusion increased the risk of developing oral mucositis ( P <0.05). Compared with wild-type (CC genotype), patients in the mutant group (CT+TT genotype) were more likely to develop myelosuppression, manifested as anemia, leucopenia, neutropenia and thrombocytopenia. However, plasma MTX level at 48 h was not associated with MTHFR C677T gene polymorphism., Conclusion: The risk of developing oral mucositis in children with mature B-cell lymphoma is associated with plasma MTX concentration. Polymorphism of MTHFR C677T gene is not related to plasma MTX concentration in children with mature B-cell lymphoma, but is related to grade III to IV hematological toxicity.

The LPS-induced RAW264. 7 cells inflammation model was used as a carrier to investigate the in vitro anti-inflammation effects of Jingfang n-butanol extraction(JFNE) isolated fraction A and explore its preliminary anti-inflammation mechanism by observing the regulatory effect on PI3 K/AKT signaling pathway and NF-κB pathway. The RAW264. 7 cells inflammation model was established by stimulating with LPS for 12 h. After 3 h pre-treatment with fraction A,the contents of interleukin-6(IL-6),interleukin-1β(IL-1β) and tumor necrosis factor(TNF-α) in the supernatant of RAW264. 7 cells inflammation model were determined by ELISA and the contents of NO in supernatant were assayed by Griess. Reverse transcription-polymerase chain reaction(RT-PCR) method was used to determine the expression of IL-6,IL-1β,TNF-α,IFN-γ,i NOS,PI3 K,AKT,CHUK,NF-κB1 and Rela mRNA in RAW264. 7 inflammatory cells,and the expression levels of phosphorylated and total PI3 K/AKT protein,NF-κB p50,p65,p-p65,p105 protein in cells were determined via Western blot. In addition,LC-MS and database were used to identify the possible chemical constituents in fraction A. The results showed that fraction A could significantly reduce the release levels of NO,IL-6,IL-1β and TNF-α in the supernatant and the expression of IL-6,IL-1β,TNF-α,IFN-γ,i NOS,PI3 K,AKT,CHUK,NF-κB1 and Rela mRNA in RAW264. 7 inflammation model cells(P<0. 05 or P<0. 01) and significantly inhibit the phosphorylation expression levels of PI3 K and AKT protein and mRNA expressions(P<0. 05 or P<0. 01). Moreover,fraction A could significantly reduce the levels of NF-κB p50,p-p65 and i NOS protein,as well as NF-κB1,Rela mRNA expressions in RAW264. 7 cells,and increase the expression of CHUK gene.A total of 196 compounds were identified from fraction A in the composition analysis,and isoobtusilactone,5-O-methyl-vismitol,emebel(embelin) and prim-O-glucosylcimifugin showed high contents. The results all above showed that fraction A had a certain antiinflammatory effect in LPS-induced RAW264. 7 inflammation model cells,and its anti-inflammatory effects may be related to its regulatory effect on the activation of PI3 K/AKT signaling pathway and NF-kappa B signaling pathway. In addition,emblin may be its effective anti-inflammation chemical composition.

To investigate the relationship between anti-depressant effect and hippocampal nerve growth of Xiaoyao San,the inflammatory model of hippocampal neuron was induced by lipopolysaccharide( LPS). The effect of Xiaoyao San serum( final concentration of4%,8%) on the cell proliferation activity was detected by immunofluorescence,the levels of BDNF and β-NGF in the supernatant of hippocampal neurons were detected by ELISA,and the expressions of BDNF,NGF,Trk B,Trk A and CREB mRNA in cell lysate of hippocampal neuron were detected by PCR. Western blot was used to detect the expressions of Trk B,CREB,p-CREB and SYP protein in cell lysate of hippocampal neuron,and to reveal the neuroprotective effect and mechanism of Xiaoyao San. The results showed that8% Xiaoyao San serum could significantly increase in Brdu/Neu N ratio( P<0. 01). 4%,8% Xiaoyao San serum could significantly improve the levels of BDNF and β-NGF in supernatant( P<0. 05 or P<0. 01),up-regulate the expression of BDNF,NGF,Trk B,Trk A,CREB mRNA and Trk B,p-CREB,SYP protein in cell lysate( P< 0. 05 or P< 0. 01). 8% Xiaoyao San serum could significantly increase CREB protein in cell lysate( P<0. 05),and elevate in p-CREB/CREB ratio( P<0. 01). All the above results indicate that Xiaoyao San has a certain protective effect on LPS induced hippocampal neuron injury,which suggests that the protective effect of Xiaoyao San is related to the promotion of hippocampal nerve growth,which is one of its antidepressant mechanisms.