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111.
Molecular Weight Affected Antioxidant,Hypoglycemic and Hypotensive Activities of Cold Water Extract from Pleurotus citrinopileatus 下载免费PDF全文
Pao‐Huei Chen Yih‐Ming Weng Shu‐Mei Lin Zer‐Ran Yu Be‐Jen Wang 《Journal of food science》2017,82(10):2456-2461
Cold water extract of P. citrinopileatus (CWEPC) was fractioned into 4 fractions, PC‐I (<1 kDa), PC‐II (1‐3.5 kDa), PC‐III (3.5‐10 kDa), and PC‐IV (>10 kDa), by ultrafiltration. The antioxidant activities, the inhibition of pancreatic α‐amylase, intestinal α‐glucosidase, and hypertension‐linked angiotensin converting enzyme (ACE), as well as the contents of polysaccharides, protein, and phenolic compounds of 4 fractions were determined. The results showed that lower MW fractions exerted a higher antioxidant activity, which was correlated to phenolic contents. The high molecular fraction (PC‐IV) exhibited significantly higher inhibitory activity on α‐amylase, α‐glucosidase, and ACE compared to CWEPC and the other 3 lower MW fractions (<10 kDa), which was more related to protein contents. The inhibition capability of CWEPC and PC‐IV on α‐amylase activity was 1/13.4 to 1/2.7 relative to that of acarbose, respectively. Kinetic data revealed that PC‐IV fraction followed a noncompetitive inhibition pattern on α‐glucosidase activity. The study demonstrated that various MW fractions and types of components contribute to different biological functions of P. citrinopileatus and it is protein constituents but not peptides responsible for the hypoglycemic potential of CWEPC. 相似文献
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Ludovic Gaudard Jeannette Gabbi Andreas Bauder Franco Romerio 《Water Resources Management》2016,30(4):1325-1343
Hydropower represents the world’s largest renewable energy source. As a flexible technology, it enhances reliability and security of the electricity system. However, climate change and market liberalization may hinder investment due to the evolution of water runoffs and electricity prices. Both alter expected revenue and bring uncertainty. It increases risk and deters investment. Our research assesses how climate change and market fluctuation affect annual revenue. But this paper focuses on the uncertainty, rather than on forecasting. This transdisciplinary topic is investigated by means of a mixed method, i.e. both quantitative and qualitative. The quantitative approach uses established models in natural sciences and economics. The uncertainty is accounted for by applying various scenarios and various datasets coming from different models. Based on those results, uncertainty is discussed through an analysis discerning three dimensions of uncertainty. Uncertainty analysis requires the assessment of a large panel of models and data sets. It is therefore rarely carried out. The originality of the paper also lies on the combination of quantitative established models with a qualitative analysis. The results surprisingly show that the greenhouse gas scenarios may in fact represent a low source of uncertainty, unlike electricity prices. Like forecasting, the main uncertainties are actually case study related and depend on the investigated variables. It is also shown that the nature of uncertainty evolves. Runoff uncertainty goes from variability, i.e. inherent randomness, to epistemic, i.e. limitation of science. The reverse situation occurs with the electricity price. The implications for scientists and policy makers are discussed. 相似文献
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Acrylate‐functionalized copolymers were synthesized by the modification of poly(butyl acrylate‐co‐glycidyl methacrylate) (BA/GMA) and poly(butyl acrylate‐co‐methyl methacrylate‐co‐glycidyl methacrylate). 13C‐NMR analyses showed that no glycidyl methacrylate block longer than three monomer units was formed in the BA/GMA copolymer if the glycidyl methacrylate concentration was kept below 20 mol %. We chemically modified the copolymers by reacting the epoxy group with acrylic acid to yield polymers with various glass‐transition temperatures and functionalities. We studied the crosslinking reactions of these copolymers by differential scanning calorimetry to point out the effect of chain functionality on double‐bond reactivity. Films formed from acrylic acrylate copolymer precursors were finally cured under ultraviolet radiation. Network heterogeneities such as pendant chains and highly crosslinked microgel‐like regions greatly influenced the network structure and, therefore, its viscoelastic properties. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 753–763, 2002 相似文献
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Due to its ability to account for discontinuities, the discontinuous Galerkin (DG) method presents two main advantages for modeling crack initiations and propagation. On the one hand, it provides an easy way to insert the cohesive elements during the simulation and therefore avoids the drawbacks inherent to the use of an extrinsic cohesive law. On the other hand, the capture of complex crack path requires very thin meshes, and the recourse to a parallel implementation of DG formulations exhibits a high scalability of the resolution scheme. Recently, the authors developed such a DG-fracture framework for Kirchhoff-Love shells in the linear and non-linear ranges. They proved that this framework dissipates, during the fracture process, an amount of energy equal to the fracture energy of the material and that the model is able to propagate the crack with the right speed. In this paper, novel numerical benchmarks are presented to validate the method in various fracture conditions. The two first ones include an initial notch and study the fracture propagation under two different dynamic loadings (impact and blast). The two other ones focus on the fragmentation of initially unbroken specimens due to uniform expansion, in order to demonstrate the ability of the new framework to model crack initiations. Results are in all cases in agreement with the ones reported in the literature. 相似文献
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S. Pos?i?il F. Be?vá? C. Granja Bustamante J. Kuba?ta S. A. Telezhnikov 《Journal of research of the National Institute of Standards and Technology》2000,105(1):173-176
The 158Gd(n,γ)159Gd reaction was studied at 12 isolated neutron resonances by the TOF method at the IBR-30 Fast Pulse Reactor at JINR Dubna. Totally 15 secondary γ transitions in 159Gd were recorded in the range from 450 keV to 750 keV. Of these, six previously unseen transitions were placed on the established 159Gd level scheme. The depopulation of strongly populated levels at 507.7 keV and 558.2 keV (the head and the first excited members of band 1/2− [521]) was observed for the first time. It was shown that the observed 507.7 keV γ line, masked by the annihilation peak, originates from an unresolved doublet of transitions from the 507.7 keV level to the ground state and from the 558.2 keV level to the level at 50.7 keV. The 507.7 keV level decays exclusively to the ground state, while the 558.2 keV level decays via two transitions with a branching ratio that agrees well with the prediction according to Alaga’s rule. 相似文献
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Zsolt Pónya Ilaria Corsi Richárd Hoffmann Melinda Kovács Anikó Dobosy Attila Zoltán Kovács Mauro Cresti Beáta Barnabás 《International journal of molecular sciences》2014,15(12):23766-23791
During in vitro fertilization of wheat (Triticum aestivum, L.) in egg cells isolated at various developmental stages, changes in cytosolic free calcium ([Ca2+]cyt) were observed. The dynamics of [Ca2+]cyt elevation varied, reflecting the difference in the developmental stage of the eggs used. [Ca2+]cyt oscillation was exclusively observed in fertile, mature egg cells fused with the sperm cell. To determine how [Ca2+]cyt oscillation in mature egg cells is generated, egg cells were incubated in thapsigargin, which proved to be a specific inhibitor of the endoplasmic reticulum (ER) Ca2+-ATPase in wheat egg cells. In unfertilized egg cells, the addition of thapsigargin caused an abrupt transient increase in [Ca2+]cyt in the absence of extracellular Ca2+, suggesting that an influx pathway for Ca2+ is activated by thapsigargin. The [Ca2+]cyt oscillation seemed to require the filling of an intracellular calcium store for the onset of which, calcium influx through the plasma membrane appeared essential. This was demonstrated by omitting extracellular calcium from (or adding GdCl3 to) the fusion medium, which prevented [Ca2+]cyt oscillation in mature egg cells fused with the sperm. Combined, these data permit the hypothesis that the first sperm-induced transient increase in [Ca2+]cyt depletes an intracellular Ca2+ store, triggering an increase in plasma membrane Ca2+ permeability, and this enhanced Ca2+ influx results in [Ca2+]cyt oscillation. 相似文献
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