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21.
Phlorizin from apple peel has been used as a nutrient for more than 100 years. The present study investigated the effects of phlorizin on the antioxidant capacity and the antioxidative mechanisms in hamsters fed high‐fat diet supplemented with phlorizin (0.3, 0.6, and 0.9%). Results showed that phlorizin increased the antioxidant enzyme activities and reduced the malondialdehyde content in plasma, liver, heart, and kidney that might arise from the higher mRNA levels of CuZn‐superoxide dismutase, Mn‐superoxide dismutase (Mn‐SOD), catalase, glutathione peroxidase, nuclear factor erythroid 2‐related factor 2‐like (Nrf2), and the protein expression of Mn‐SOD (p < .05). Diet supplemented with phlorizin also significantly decreased the total cholesterol and triglycerides levels in plasma. The present study demonstrated that phlorizin might reduce lipid peroxidation and protect against cardiovascular issues in vivo.

Practical applications

Phlorizin, from apple peel, has been used as a nutrient for over 100 years. To date, despite extensive research on phlorizin, a report on its effect on lipid peroxidation, the antioxidant system in plasma, heart, liver, and kidney of hamsters fed high‐fat diet is yet lacking. This report demonstrates that phlorizin can reduce lipid peroxidation and exert a protective effect on cardiovascular issues in vivo, which is valuable in the rational utilization of phlorizin in functional foods.  相似文献   
22.
The effect of the support nature and metal dispersion on the performance of Pt catalysts during steam reforming of ethanol was studied. H2 and CO production was facilitated over Pt/CeO2 and Pt/CeZrO2, whereas the acetaldehyde and ethene formation was favored on Pt/ZrO2. According to the reaction mechanism, determined by temperature-programmed desorption (TPD) and Diffuse Reflectance Infrared Spectroscopy (DRIFTS) analysis, some reaction pathways are favored depending on the support nature, which can explain the differences observed on the resulting product distribution.  相似文献   
23.
Ss judged whether 2 successive line segments had the same orientation. The pairs were lateralized, and the location on the screen and the distance between the segments in a pair were varied. When stimuli were relatively close to the center of the screen, Ss evaluated segments that were relatively far apart more quickly when they were presented in the left visual field and tended to judge segments that were close together more quickly when they were presented in the right visual field. In contrast, when the line segments were moved into the periphery, the previous pattern of results was reversed. In addition, results in a second block of trials depended on how attention had been set in the 1st set of trials. The observed hemispheric differences were due to attentional effects, not stable physiological properties of the brain. Previously observed hemispheric differences in spatial frequency analysis could reflect attentional biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
An experimental study of the blending, thermal transitions, phase morphology, and mechanical properties of poly(p-phenylene sulfide) (PPS)/polyamide blends is presented. Nylon-6, rubber modified nylon-6, nylon-66, nylon-11, nylon-12, and two partially aromatic amorphous polyamides were included in the study. Generally, blends of PPS with aromatic amorphous polyamides exhibit better mechanical properties than those with aliphatic polyamides. The blends with nylon-12 exhibit the best characteristics among the aliphatic polyamides.  相似文献   
25.
LaNi(1−x)FexO3 (x=0, 0.2, 0.4 and 0.7) perovskite-type catalysts were modified by the partial substitution of nickel by iron, aiming to increase the stability and resistance to carbon deposition during the methane dry reforming reaction. The results showed that a suitable combination of precipitation and calcination steps could result in oxides with the desired structure and with improved properties from the point of view of heterogeneous catalysis. The partial substitution of Ni by Fe in the perovskite structure resulted in decreasing rates of conversion of both reactants. However, the stability of the catalyst during the reaction was highly increased. These substituted catalysts were shown to be stable and the LaNi0.8Fe0.2O3 catalyst, calcined at 800 °C for 5 h, was the most active in the reaction conditions.  相似文献   
26.
The biosynthesis of silver nanoparticles (AgNPs) is substantial for its application in lots of fields. Tomato and grape fruit juices were used as a reducing and capping agents for the biosynthesis of AgNPs. Ultraviolet spectroscopic analysis offered peaks in the range of 396‒420 nm that indicate the production of AgNPs. Fourier transform infrared spectroscopy analysis revealed attachment of different functional groups with Ag ion in both tomato and grape fruit extracts NPs. The X‒ray diffraction analysis confirmed that the synthesised AgNPs have a face centred cubic confirmation. Scanning electron microscopy confirms the size of NPs that varies from 10 to 30 nm. The DPPH free radical scavenging assay, total antioxidant capacity, reducing power assay, total flavonoid contents and total phenolic contents determination confirmed that synthesised AgNPs are potent antioxidant agents; can be used as an effective scavenger of free radicals. Biosynthesised AgNPs also showed good antibacterial activity against Pseudomonas septica, Staphylococcus aureus, Micrococcus luteus, Enterobacter aerogenes, Bacillus subtilis and Salmonella typhi. Protein kinase inhibition activity showed a clear zone which indicates anticancerous potential of biosynthesised AgNPs. The efficacious bioactivities indicate that the tomato and grape derived AgNPs can be used efficiently in pharmaceutical and medical industries.Inspec keywords: silver, nanoparticles, nanomedicine, biomedical materials, nanofabrication, Fourier transform infrared spectra, X‐ray diffraction, scanning electron microscopy, microorganisms, antibacterial activity, enzymes, cancer, ultraviolet spectraOther keywords: silver nanoparticle green synthesis, grape juice, tomato juice, biological activity evaluation, ultraviolet spectroscopic analysis, silver nanoparticle production, Fourier transform infrared spectroscopy analysis, silver ion, X‐ray diffraction analysis, scanning electron microscopy, DPPH free radical scavenging assay, antioxidant capacity, flavonoid content, phenolic content determination, antioxidant agent, antibacterial activity, Pseudomonas septica, Staphylococcus aureus, Micrococcus luteus, Enterobacter aerogenes, Bacillus subtilis, Salmonella typhi, protein kinase, size 10 nm to 30 nm  相似文献   
27.
Poly(N-isopropylmethacrylamide-co-methacrylic acid) [p(NipAam-Mac)] microgels were synthesized and used as microreactors to fabricate silver nanoparticles. Pure and hybrid microgels were characterized using Ultraviolet–Visible (UV/Vis) spectroscopy, Fourier transform infra-red (FTIR) spectroscopy and transmission electron microscopy (TEM). Catalytic activity of hybrid microgels and mechanism of catalysis by this system was explored using different reaction conditions. At the same temperature, apparent rate constant (kapp) was found to be varied from 0.0414 to 0.7852 min?1 by increasing the concentration of NaBH4 from 2.49 to 22.41 mM at constant concentration of substrate and catalyst. However upon extra increase in concentration of NaBH4 from 22.41 to 37.35 mM reduced the value of kapp to 0.2178 min?1. Likewise, the value of kapp was found to be increased from 0.1242 to 0.5495 min?1 with increasing the concentration of 4-nitrophenol [Para-nitrophenol (p-Np)] from 0.063 to 0.079 mM keeping other parameters constant. Further increase in concentration of p-Np caused decline in the value of kapp. Kinetic data reveals that catalytic reduction of p-Np obeys Langmuir–Hinshelwood mechanism and p-Np is converted to p-Ap on the surface of the silver nanoparticles passing through various reaction intermediates.  相似文献   
28.
Copper oxide nanoparticles (CuO NPs) use has exponentially increased in various applications (such as industrial catalyst, gas sensors, electronic materials, biomedicines, environmental remediation) due to their flexible properties, i.e. large surface area to volume ratio. These broad applications, however, have increased human exposure and thus the potential risk related to their short‐ and long‐term toxicity. Their release in environment has drawn considerable attention which has become an eminent area of research and development. To understand the toxicological impact of CuO NPs, this review summarises the in‐vitro and in‐vivo toxicity of CuO NPs subjected to species (bacterial, algae, fish, rats, human cell lines) used for toxicological hazard assessment. The key factors that influence the toxicity of CuO NPs such as particle shape, size, surface functionalisation, time–dose interaction and animal and cell models are elaborated. The literature evidences that the CuO NPs exposure to the living systems results in reactive oxygen species generation, oxidative stress, inflammation, cytotoxicity, genotoxicity and immunotoxicity. However, the physio‐chemical characteristics of CuO NPs, concentration, mode of exposure, animal model and assessment characteristics are the main perspectives that define toxicology of CuO NPs.Inspec keywords: catalysts, nanofabrication, reviews, oxidation, toxicology, gas sensors, cellular biophysics, copper compounds, nanoparticles, biochemistryOther keywords: copper oxide nanoparticles, environmental remediation, short‐ term toxicity, long‐term toxicity, human cell lines, CuO NPs exposure, physiochemical characteristics, mode of exposure, animal model, ssessment characteristics, toxicology, time‐dose interaction, oxidative stress, inflammation, cytotoxicity, genotoxicity, immunotoxicity, toxicological hazard assessment, algae species, bacterial species, fish, rats, CuO  相似文献   
29.
Source separation algorithms based on spatial cues generally face two major problems. The first one is their general performance degradation in reverberant environments and the second is their inability to differentiate closely located sources due to similarity of their spatial cues. The latter problem gets amplified in highly reverberant environments as reverberations have a distorting effect on spatial cues. In this paper, we have proposed a separation algorithm, in which inside an enclosure, the distortions due to reverberations in a spatial cue based source separation algorithm namely model‐based expectation‐maximization source separation and localization (MESSL) are minimized by using the Precedence effect. The Precedence effect acts as a gatekeeper which restricts the reverberations entering the separation system resulting in its improved separation performance. And this effect is automatically transformed into the Clifton effect to deal with the dynamic acoustic conditions. Our proposed algorithm has shown improved performance over MESSL in all kinds of reverberant conditions including closely located sources. On average, 22.55% improvement in SDR (signal to distortion ratio) and 15% in PESQ (perceptual evaluation of speech quality) is observed by using the Clifton effect to tackle dynamic reverberant conditions.  相似文献   
30.
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