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1.
Appl Opt ; 63(4): 888-894, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437384

RESUMO

An electromagnetic wavefront can be flexibly manipulated by discrete phase coding on the coding unit. In this paper, we designed two coding metasurfaces with 1-bit and 3-bit based on active tuning of Dirac semimetals by controlling the Fermi level (E F) with an external polarization voltage. The size and structure of the metasurface remain unchanged with this strategy. Both designs were found to be dynamically tunable. The 1-bit coding metasurface enables beam conversion, single-focus switching, and switching between single-focus and multi-focus. On the other hand, the 3-bit coding metasurface enables the switching between vortex beams and single-beam mirror reflections. These proposed structures have potential applications in terahertz (THz) communications and terahertz-focused imaging, opening up new possibilities for the dynamic modulation of THz waves.

2.
Micromachines (Basel) ; 15(6)2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38930762

RESUMO

The mode rotator is an important component in a PLC-based mode-division multiplexing (MDM) system, which is used to implement high-order modes with vertical intensity peaks, such as LP11b mode conversions from LP11a in PLC chips. In this paper, an LP11 mode rotator based on a polymer/silica hybrid inverted ridge waveguide is demonstrated. The proposed mode rotator is composed of an asymmetrical waveguide with a trench. According to the simulation results, the broadband conversion efficiency between the LP11a and LP11b modes is greater than 98.5%, covering the C-band after optimization. The highest mode conversion efficiency (MCE) is 99.2% at 1550 nm. The large fabrication tolerance of the proposed rotator enables its wide application in on-chip MDM systems.

3.
Food Chem ; 460(Pt 3): 140745, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39126945

RESUMO

An antioxidant amyloid fibril was prepared as an emulsifier by fibrillating limited enzymatic hydrolysis-modified rice protein (HRP). The purpose of this study was to investigate the feasibility of using fibrillated HRP to stabilize oil-in-water emulsion. A free radical scavenging assay revealed that the antioxidant activity of fibrillated HRP was 2.09 times higher than that of native rice protein. Fibrillated HRP demonstrated a marked reduction in interfacial tension, increased surface hydrophobicity and contact angle (> 80°), and rapid adsorption to the interface, with 35.34 ± 2.43% interfacial adsorbed protein content. The fibrillated HRP barriers resisted environment stresses such as NaCl, pH variations, long-term storage, while reducing lipid oxidation degree. Additionally, fibrillated HRP-based emulsion was more effective in protecting ß-carotene from degradation compared to other samples. These findings provide theoretical support for the development of rice protein-based antioxidant emulsifiers and modification of emulsifying properties of plant proteins.

4.
Ecol Evol ; 14(6): e11600, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38903147

RESUMO

Species geographic distribution and conservation priority areas are important bases for in situ biodiversity conservation and conservation decision-making. In view of the urgency of endangered species protection, eight representative endangered species in the typical forest ecosystem of the Greater and Lesser Khingan Mountains were studied. Based on 1127 occurrence points and environmental data collected from 2016 to 2021, used BIOMOD2 and Zonation to reconstruct the potential distribution area and identify conservation priority areas of eight species (Tetrao parvirostris, T. tetrix, Gulo gulo, Alces alces, Martes zibellina, Moschus moschiferus, Lynx lynx, Lutra lutra). The results showed potential distribution areas for almost all species concentrated in the northern part of the Greater Khingan Mountains (GKM) and the central part of the Lesser Khingan Mountains (LKM). The potential distribution areas of each species were as follows: black-billed capercaillie, 102,623 km2; black grouse, 162,678 km2; wolverine, 63,410 km2; moose, 140,287 km2; sable, 112,254 km2; Siberian musk deer, 104,787 km2; lynx, 139,912 km2; and Eurasian otter, 49,386 km2. Conservation priority areas (CPAs) clustered in the north GKM and central LKM and totaled 220,801 km2, and only 16.94% of the CPAs were currently protected by nature reserves. We suggest that the Chinese government accelerate the integration of existing protected areas in the northern GKM and establish a larger GKM National Park based on cost-effective multi-species protection.

5.
JHEP Rep ; 6(8): 101101, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39091991

RESUMO

Background & Aims: Persistent cholestasis has been associated with poor prognosis after orthotopic liver transplantation. In this study, we aimed to investigate how the accumulation of tauro-beta-muricholic acid (TßMCA), resulting from the reprogramming of bile acid (BA) metabolism during liver ischemia/reperfusion (IR) stress, attenuates liver inflammation. Methods: Ingenuity Pathway Analysis was performed using transcriptome data from a murine hepatic IR model. Three different models of hepatic IR (liver warm IR, bile duct separation-IR, common bile duct ligation-IR) were employed. We generated adeno-associated virus-transfected mice and CD11b-DTR mice to assess the role of BAs in regulating the myeloid S1PR2-GSDMD axis. Hepatic BA levels were analyzed using targeted metabolomics. Finally, the correlation between the reprogramming of BA metabolism and hepatic S1PR2 levels was validated through RNA-seq of human liver transplant biopsies. Results: We found that BA metabolism underwent reprogramming in murine hepatocytes under IR stress, leading to increased synthesis of TßMCA, catalyzed by the enzyme CYP2C70. The levels of hepatic TßMCA were negatively correlated with the severity of hepatic inflammation, as indicated by the serum IL-1ß levels. Inhibition of hepatic CYP2C70 resulted in reduced TßMCA production, which subsequently increased serum IL-1ß levels and exacerbated IR injury. Moreover, our findings suggested that TßMCA could inhibit canonical inflammasome activation in macrophages and attenuate inflammatory responses in a myeloid-specific S1PR2-GSDMD-dependent manner. Additionally, Gly-ßMCA, a derivative of TßMCA, could effectively attenuate inflammatory injury in vivo and inhibit human macrophage pyroptosis in vitro. Conclusions: IR stress orchestrates hepatic BA metabolism to generate TßMCA, which attenuates hepatic inflammatory injury by inhibiting the myeloid S1PR2-GSDMD axis. Bile acids have immunomodulatory functions in liver reperfusion injury that may guide therapeutic strategies. Impact and implications: Our research reveals that liver ischemia-reperfusion stress triggers reprogramming of bile acid metabolism. This functions as an adaptive mechanism to mitigate inflammatory injury by regulating the S1PR2-GSDMD axis, thereby controlling the release of IL-1ß from macrophages. Our results highlight the crucial role of bile acids in regulating hepatocyte-immune cell crosstalk, which demonstrates an immunomodulatory function in liver reperfusion injury that may guide therapeutic strategies targeting bile acids and their receptors.

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