Hypolipidaemic and antioxidant properties of ethanol extract from <i>Flos populi</i>

<div><p>This study was undertaken to evaluate antihyperlipidaemic and <i>in vitro</i> antioxidant activity of ethanolic extract of <i>Flos populi</i> (EFP). The results demonstrated that EFP contains 78.5% flavonoids and 10.4% phenolics, and it exhibited free radical-scavenging activity on 2,2-diphenyl-picrylhydrazyl (IC₅₀ 36.40 ± 0.62 μg/mL) and high reducing power (EC₅₀ 206.32 ± 1.6l μg/mL) under <i>in vitro</i> chemical assays. And irrespective of prophylactic administration or remedial administration, in high fat diet-induced hyperlipidaemic mice, oral treatment with EFP produced a decrease in the levels of serum total cholesterol, triglycerides, low-density lipoprotein-cholesterol and increase in high-density lipoprotein-cholesterol. In a word, in high fat diet-fed hyperlipidaemic mice, EFP (100, 200 and 400 mg/kg) significantly altered the plasma lipid levels to near normal. These results support a potential effect of EFP in cardiovascular disease.</p></div

Metasurface spectrometers beyond resolution-sensitivity constraints

Optical spectroscopy plays an essential role across scientific research and industry for non-contact materials analysis1-3, increasingly through in-situ or portable platforms4-6. However, when considering low-light-level applications, conventional spectrometer designs necessitate a compromise between their resolution and sensitivity7,8, especially as device and detector dimensions are scaled down. Here, we report on a miniaturizable spectrometer platform where light throughput onto the detector is instead enhanced as the resolution is increased. This planar, CMOS-compatible platform is based around metasurface encoders designed to exhibit photonic bound states in the continuum9, where operational range can be altered or extended simply through adjusting geometric parameters. This system can enhance photon collection efficiency by up to two orders of magnitude versus conventional designs; we demonstrate this sensitivity advantage through ultra-low-intensity fluorescent and astrophotonic spectroscopy. This work represents a step forward for the practical utility of spectrometers, affording a route to integrated, chip-based devices that maintain high resolution and SNR without requiring prohibitively long integration times