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1.
Proc Natl Acad Sci U S A ; 121(6): e2309096120, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38285934

RESUMEN

Invisibility, a fascinating ability of hiding objects within environments, has attracted broad interest for a long time. However, current invisibility technologies are still restricted to stationary environments and narrow band. Here, we experimentally demonstrate a Chimera metasurface for multiterrain invisibility by synthesizing the natural camouflage traits of various poikilotherms. The metasurface achieves chameleon-like broadband in situ tunable microwave reflection mimicry of realistic water surface, shoal, beach/desert, grassland, and frozen ground from 8 to 12 GHz freely via the circuit-topology-transited mode evolution, while remaining optically transparent as an invisible glass frog. Additionally, the mechanic-driven Chimera metasurface without active electrothermal effect, owning a bearded dragon-like thermal acclimation, can decrease the maximum thermal imaging difference to 3.1 °C in tested realistic terrains, which cannot be recognized by human eyes. Our work transitions camouflage technologies from the constrained scenario to ever-changing terrains and constitutes a big advance toward the new-generation reconfigurable electromagnetics with circuit-topology dynamics.

2.
Opt Lett ; 49(19): 5579-5582, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39353011

RESUMEN

Integrated power dividers (PDs) are essential in terahertz (THz) communication and radar systems, but miniaturization often leads to performance degradation due to fabrication inaccuracies and sharp bends. Topological photonics offers a solution to these issues, yet creating THz power dividers with arbitrary splitting ratios remains challenging. We present a design methodology for on-chip topological THz power dividers with customizable splitting ratios using valley-locked photonic crystals. These crystals feature a tri-layered structure with two distinct valley Chern number layers and an intermediate semimetal layer. Utilizing the Jackiw-Rebbi model, we show that the characteristic impedance of the valley-locked photonic crystals, and thus the power division ratio, can be tuned by adjusting the semimetal layer width. Our approach is validated through simulations and experiments for both equal (1:1) and unequal (4:9) power ratios. This method enables efficient navigation around sharp bends and robust THz on-chip connectivity.

3.
J Ethnopharmacol ; 324: 117758, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38246481

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Sorbaria sorbifolia (SS) is a traditional Chinese medicine (TCM) that has been employed anti-hepatocellular carcinoma (HCC) for over 2000 years; yet, its underlying mechanism is still not fully understood. AIM OF THE STUDY: In this study, we evaluated the anti-HCC effect on the freeze-dried powder of the water extract of SS (FDSS) by inhibiting tumor-induced neovascularization, and promoting apoptosis, and elucidated the underlying mechanisms. MATERIALS AND METHODS: HCC cell lines (HepG2 and Huh7 cells) and HepG2 xenograft tumors in zebrafish were employed as in vivo and in vitro models, respectively, to evaluate the anti- HCC-indued neovascularization and apoptosis. In HCC cell lines, CCK-8 assay, wound-healing assay, transwell assay, cell circle assay, apoptosis assay, transmission electron microscopy, and co-culture assay were performed in vitro; in HepG2 xenograft tumor-zebrafish, tumor growth inhibition assay, hematoxylin and eosin (HE) staining, xenograft tumor-zebrafish apoptosis assay, and HCC-indued neovascularization assay were performed to evaluate the effect of FDSS on biological behavior of tumor, HCC-indued neovascularization, and apoptosis. The expression of VEGFR and c-Met/apoptotic pathway-related proteins was detected by western blotting analysis. Assays for c-Met and VEGFR activation were conducted to assess the impact of FDSS in either agonistic or inhibitory roles on these receptor proteins. RESULTS: The findings from our study revealed that FDSS effectively suppresses the proliferation, migration, and invasion of HepG2 and Huh7 cells, as well as inhibiting tumor growth in the HepG2 xenograft zebrafish model by downregulating the expression of p-Met and p-AKT proteins. FDSS decreased the tumor growth associated with promoting apoptosis, including arresting HepG2 and Huh7 cells cycle at G0/G1phase, increasing apoptotic cell numbers and apoptotic bodies in cancer cells, and increasing the apoptotic fluorescence of xenograft tumor zebrafish by downregulating Bcl-2 proteins and upregulating Bax, caspase-9, and caspase-3 levels. We also found that FDSS can inhibit HCC-induced neovascularization and regulate VEGFR. Using an agonist or inhibitor of c-Met and VEGFR in HepG2 cells, we discovered that FDSS can downregulate c-Met and VEGFR protein expression. CONCLUSION: FDSS exerts an anti-HCC effect by inhibiting HCC-indued neovascularization and pro-apoptosis through the inhibition of the action of VEGFR and c-Met/apoptotic pathway.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Pez Cebra , Antineoplásicos/farmacología , Línea Celular Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Reguladoras de la Apoptosis , Apoptosis , Proliferación Celular
4.
Chin J Traumatol ; 8(6): 383-4, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16313718

RESUMEN

As an emergency, a foreign body in the heart should generally be removed as early as possible by surgical or non-surgical procedures in order to avoid any complications. Early treatment typically results in a better prognosis.

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