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721.
Degrees of Antioxidant Protection: A 2‐Year Study of the Bioactive Properties of Organic Milk in Poland 下载免费PDF全文
Kamila Puppel Tomasz Sakowski Beata Kuczyńska Grzegorz Grodkowski Marcin Gołębiewski Jerzy Barszczewski Barbara Wróbel Arkadiusz Budziński Aleksandra Kapusta Marek Balcerak 《Journal of food science》2017,82(2):523-528
The aim of this study was to determine the nutritional value of organic milk in Poland, investigate the influence of diet on antioxidant capacity and degree of antioxidant protection (DAP), and to examine the effect of season on the bioactive properties of milk from organic farms. From 2014 to 2015, 820 milk samples were collected from 6 organic farms during indoor feeding season (IDS) and pasture feeding season (PS). Pasture feeding season + corn grain (PSCG) cows’ daily ration during pasture feeding season was enriched with 4 kg a day of corn to improve dietary energy balance. Milk obtained during PS was found to have a higher fat content, slight but significantly lower protein content compared with milk from IDS. The study showed that the content of monounsaturated fatty acids (MUFA) in milk fat was strongly linked to the concentration of polyunsaturated fatty acids (PUFA) and, to a lesser extent, on the supply of MUFA. The IDS data (concentration of vitamin E, A, and β‐carotene) showed the lowest values compared with the PS and PSCG groups. Total antioxidant status (TAS) and DAP showed an increasing trend in organic milk. PSCG was associated with highest level of DAP (9% higher than PS and 79% higher than IDS) and TAS (37% higher than PS and 79% higher than IDS). The results obtained show that supplementation of the basic ration with corn grain improved both TAS and DAP. The higher DAP and TAS value is responsible for product stability, considering the risk factor related to levels of cholesterol‐oxide intake in humans. 相似文献
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E. Rozenberg 《Journal of Superconductivity and Novel Magnetism》2010,23(2):183-186
In a recent paper (Chen et al. in J. Supercond. Nov. Magn. 22:465, 2009) Zhenping Chen et al. reported measurements of the electrical resistivity (ρ) and magnetization versus temperature (T) and magnetic field (H) on polycrystalline manganite compound La2/3Ca1/3MnO3. In particular, the ρ(T) dependence shows a shallow minimum at T
min∼20 K. Application of the external H up to 8 T leads to marked flattening of such minimum and to notable lowering of the T
min on ρ(T,H) curves. The authors attributed this low-temperature anomaly to competitive quantum Kondo effect and three-dimensional electron–electron
interaction, using the results of numerical fittings of ρ versus T and H dependences in the interval of about 5–30 K. It is suggested in the comment that such a claim seems to be doubtful due to
the fundamental inapplicability of this approach for analysis of low-temperature conductivity in polycrystalline manganites.
It is noted that a natural cause for both the low-temperature minimum on ρ(T) curve and its evolution upon magnetic field application, is the well-known grain boundary effect. The numerous uncertainties
and obscurities are also characteristic for the paper being commented upon. 相似文献
724.
Dominika Komorowska Agnieszka Gajewska Pawe Hikisz Grzegorz Bartosz Aleksandra Rodacka 《International journal of molecular sciences》2021,22(17)
Radiotherapy is among the most important methods for breast cancer treatment. However, this method’s effectiveness is limited by radioresistance. The aim of this study was to investigate whether the stilbene derivatives piceid, resveratrol, and piceatannol have a radiosensitising effect on breast cancer cells (MCF-7). The conducted research enabled us to determine which of the tested compounds has the greatest potential in sensitising cells to ionising radiation (IR). Among the stilbene derivatives, resveratrol significantly increased the effect of IR. Resveratrol and IR used in combination had a higher cytotoxic effect on MCF-7 cells than using piceatannol, piceid, or radiation alone. This was due to a significant decrease in the activity of antioxidant enzymes, which resulted in the accumulation of formed reactive oxygen species (ROS). The effect of resveratrol and IR enhanced the expression of apoptotic genes, such as Bax, p53, and caspase 8, leading to apoptosis. 相似文献
725.
Leszek Zaraska Grzegorz D. Sulka Marian Jasku?a 《Surface & coatings technology》2010,205(7):2432-2437
The through-hole porous anodic aluminum oxide (AAO) membranes were fabricated by a two-step anodization of the aluminum alloy (AA1050) in 0.3 M oxalic acid at 45 V and 20 °C followed by removal of Al and pore opening/widening procedures. The effect of duration of the second anodizing step on the porous oxide layer thickness and the influence of the pore opening time on structural features of as-prepared membranes were studied in detail. The prepared membranes with a thickness of about 60 μm were used as templates for fabrication of dense arrays of Ag, Au, and Sn nanowires with various aspect ratios by a DC electrochemical deposition process. The successful synthesis of metallic nanowires by simple DC electrodeposition of metals inside the pores of AAO templates fabricated from the AA1050 alloy was reported for the first time. The fabrication costs of nanowire arrays can be reduced by about 500 times when AAO templates, prepared from the AA1050 alloy, are used instead of those usually formed from expensive high purity Al. 相似文献
726.
This paper reports on the MIZAR formalization of the theory of continuous lattices as presented in Gierz et al.: A Compendium of Continuous Lattices, 1980. By a MIZAR formalization we mean a formulation of theorems, definitions, and proofs written in the MIZAR language whose correctness is verified by the MIZAR processor. This effort was originally motivated by the question of whether or not the MIZAR system was sufficiently developed for the task of expressing advanced mathematics. The current state of the formalization – 57 MIZAR articles written by 16 authors – indicates that in principle the MIZAR system has successfully met the challenge. To our knowledge it is the most sizable effort aimed at mechanically checking some substantial and relatively recent field of advanced mathematics. However, it does not mean that doing mathematics in MIZAR is as simple as doing mathematics traditionally (if doing mathematics is simple at all). The work of formalizing the material of the Gierz et al. compendium has (i) prompted many improvements of the MIZAR proof checking system, (ii) caused numerous revisions of the the MIZAR data base, and (iii) contributed to the to do list of further changes to the MIZAR system. 相似文献
727.
Grzegorz Róg 《Electrochimica acta》1977,22(7):697-699
Solid electrolytes based on stabilized zirconia (or thoria) cannot be used to the construction of the solid galvanic cells for the study of thermodynamic properties of the alkaline earths silicates. They become a partially electronic conductors of low chemical potentials of oxygen, as those in the coexisting alkaline earths silicate phases.It was attempted to use as the solid electrolyte a mixture of small amounts of alkaline earth fluoride in the corresponding silicate. Then, the solid galvanic cells consisting of such electrolytes were applied to the determination of the standard Gibbs free energies of formation of some magnesium, strontium and barium silicates. 相似文献
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