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1.
Phys Rev Lett ; 128(21): 217401, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35687444

RESUMO

Direct electrical tuning of localized plasmons at optical frequencies boasts the fascinating prospects of being ultrafast and energy efficient and having an ultrasmall footprint. However, the prospects are obscured by the grand challenge of effectively modulating the very large number of conduction electrons in three-dimensional metallic structures. Here we propose the concept of nanoscopic electron reservoir (NER) for direct electro plasmonic and electro-optic modulation. A NER is a few-to-ten-nanometer size metal feature on a metal host and supports a localized plasmon mode. We provide a general guideline to construct highly electrically susceptible NERs and theoretically demonstrate pronounced direct electrical tuning of the plasmon mode by exploiting the nonclassical effects of conduction electrons. Moreover, we show the electro-plasmonic tuning can be efficiently translated into modulation of optical scattering by utilizing the antenna effect of the metal host for the NER. Our work extends the landscape of electro plasmonic modulation and opens appealing new opportunities for quantum plasmonics.

2.
Phys Rev Lett ; 126(25): 257401, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34241506

RESUMO

We report on the discovery and rationale to devise bright single optical eigenmodes that feature quantum-optical mode volumes of about 1 nm^{3}. Our findings rely on the development and application of a quasinormal mode theory that self-consistently treats fields and electron nonlocality, spill-out, and Landau damping around atomistic protrusions on a metallic nanoantenna. By outpacing Landau damping with radiation via properly designed antenna modes, the extremely localized modes become bright with radiation efficiencies reaching 30% and could provide up to 4×10^{7} times intensity enhancement.

3.
Gastroenterol Res Pract ; 2019: 9097276, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31263495

RESUMO

Many animal experiments and clinical trials showed that probiotics are effective for the treatment of alcoholic liver disease. Alcohol disrupts the composition of intestinal flora; probiotics modulate the gut microbiota and reverse alcohol-associated intestinal barrier dysfunction by decreasing intestinal mucosal permeability and preventing intestinal bacteria from translocating. Probiotics enhance immune responses and reduce the levels of alcohol-induced inflammatory cytokines and reactive oxygen species (ROS) production in the liver and intestine. Probiotics also increase fatty acid ß-oxidation and reduce lipogenesis, combating alcohol-induced hepatic steatosis. In this review, we summarize the current knowledge regarding the mechanism of action of probiotics for reducing the effects of alcoholic liver disease.

4.
Food Funct ; 9(11): 6020-6028, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30397690

RESUMO

Lactobacillus fermentum KP-3 was isolated from Korean pickle and used to ferment ginseng. The changes in the minor ginsenosides in the fermented ginseng were analyzed and the material was evaluated in high fat diet-fed mice. Total ginsenosides increased from 0.746 mg g-1 to 0.939 mg g-1 after fermentation, and the levels of minor ginsenosides (Rg2, Rg3, Rh1, Rh2, F2, and Ro) increased from 0.186 mg g-1 to 0.704 mg g-1. In an animal study, the serum TC and LDL levels in the HFD group were significantly higher than those of the control group. Compared with the HFD group, the probiotic-fermented ginseng significantly decreased the serum TC and LDL levels. In addition, the serum and liver ALT and AST levels were dramatically increased in the HFD group, but these increases were significantly inhibited by treatment with the probiotic-fermented ginseng. Furthermore, fermented ginseng reduced high fat diet-induced liver lipid accumulation. Overall, fermentation with L. fermentum KP-3 enhanced minor ginsenosides in ginseng and this probiotic-fermented ginseng ameliorated hyperlipidemia and liver injury induced by a high fat diet.


Assuntos
Ginsenosídeos/farmacologia , Hiperlipidemias/tratamento farmacológico , Limosilactobacillus fermentum/metabolismo , Hepatopatias/tratamento farmacológico , Panax/química , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Glicemia/metabolismo , Colesterol/sangue , Dieta Hiperlipídica , Fermentação , Microbiologia de Alimentos , Hiperlipidemias/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia , Probióticos , Triglicerídeos/sangue
5.
Int J Biol Macromol ; 82: 404-10, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26449530

RESUMO

Based on the copper (I) catalyzed Huisgen azide-alkyne cycloaddition (click chemistry), the novel synthesis of a variety of 1,2,3-triazole-linked starch derivatives was developed, including 6-hydroxymethyltriazole-6-deoxy starch (HMTST), 6-hydroxyethyltriazole-6-deoxy starch (HETST), 6-hydroxypropyltriazole-6-deoxy starch (HPTST), and 6-hydroxybutyltriazole-6-deoxy starch (HBTST). Their antioxidant properties against hydroxyl-radical, DPPH-radical, and superoxide-radical were evaluated in vitro, respectively. The antioxidant activity of the obtained novel amphiprotic starch derivatives via 'click reaction' exhibited remarkable improvement over starch. And the scavenging effect indices of most of the products were higher than 60% at 1.6 mg/mL against hydroxyl-radical and DPPH-radical. Moreover, the scavenging effect of the products against superoxide-radical attained 90% above at 0.1mg/mL. Generally, the antioxidant activity decreased in the order: HBTST>HPTST>HETST>HMTST>starch. Furthermore, the order of their antioxidant activity was consistent with the electron-donating ability of different substituted groups of the 1,2,3-triazoles. The substituted groups with stronger electron supplying capacity provided more electrons to the various radicals, which relatively enhanced the capacity for scavenging free radicals.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Química Click , Amido/química , Amido/farmacologia , Triazóis/química , Antioxidantes/síntese química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Espectroscopia de Ressonância Magnética , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/análogos & derivados , Amido/síntese química
6.
Carbohydr Polym ; 121: 315-9, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25659704

RESUMO

The tubers of Jerusalem artichoke are rich of inulin, which makes the plant one of primary inulin resources in China. The aim of this study was to extract inulin from tubers and test the degree of polymerization (DP) 10 days before flowering to 80 days after flowering. The DP of inulin reaches a maximum of 19 at 50 days after flowering. The variation tendencies of inulin content and DP were almost the same, which increase rapidly at the beginning and then decrease gradually at a lower speed. Meanwhile, the effects of inulin on probiotics in yogurt have been evaluated. It indicated that inulin with low DP has higher activities. Experimental data improve the understanding of status change of inulin in whole growth of Jerusalem artichoke tubers in Northeastern China and are instructive to get inulin with different properties.


Assuntos
Cynara scolymus/química , Inulina/química , Prebióticos , Bifidobacterium/efeitos dos fármacos , Inulina/farmacologia , Lactobacillus/efeitos dos fármacos , Polimerização
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