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61.
Piotr Hanczakowski Ewa Hanczakowska Bogumila Skraba 《Journal of the science of food and agriculture》1982,33(3):244-248
The biological value (BV) and true digestibility of lucerne and barley juice protein mixed with ground barley grain were estimated using the Thomas-Mitchell balance method with rats. The BV with forage barley juice protein was similar to that of barley grain protein alone and was not improved by any of the applied treatments. The BV with lucerne juice protein was lower and was improved by separating the ‘brown juice’ after heat coagulation. Better results were obtained in a group fed diets with lowered levels of potassium and calcium which suggested an imbalance in the mineral content of lucerne juice; there was no difference in water consumption. The haemoglobin content of the blood of rats fed lucerne or barley juice alone was lower than that of animals fed plant juice/barley grain mixtures. No pathological lesions were observed in the guts, kidneys and livers of the rats. 相似文献
62.
Kacper Przykaza Klaudia Woźniak Małgorzata Jurak Agnieszka Ewa Wiącek 《Journal of surfactants and detergents》2019,22(5):1213-1228
Polyetheretherketone (PEEK) is a highly biocompatible polymer widely used in medicine as an implant production material. In this article, the PEEK surface was characterized in terms of its wettabillity properties after the physicochemical modifications by treatment with the low-temperature air plasma and covering with the Langmuir–Blodgett (LB) monolayers of polypeptide (cyclosporine A, CsA) and/or phospholipid (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC). The LB deposition was preceded by the analysis of miscibility and morphology of monolayers at the air/water interface by means of the Langmuir technique and Brewster angle microscopy (BAM). Then, wettability of the polymer-supported films was evaluated by the contact angle measurements of three probe liquids of different characters (two polar—water and formamide, one apolar—diiodomethane). The measured contact angles allowed for determination of the surface free energy and its components based on the Lifshitz-van der Waals/acid–base (LWAB) approach. Some relations between the kind and magnitude of interactions within the model membranes on the water subphase and those of the PEEK-supported membranes with the liquids were found out. The results allowed obtaining the interesting models of biological coatings with potential applications. 相似文献
63.
The aim of this study was to investigate whether there are differences in technique between young adults with and without musculoskeletal symptoms when using a mobile phone for texting and whether there are differences in muscle activity and kinematics between different texting techniques. A total of 56 young adults performed a standardised texting task on a mobile phone. Their texting techniques were registered using an observation protocol. The muscular activity in six muscles in the right forearm/hand and both shoulders were registered by surface electromyography and the thumb abduction/adduction and flexion/extension were registered using a biaxial electrogoniometer. Differences in texting techniques were found between the symptomatic and the asymptomatic group, with a higher proportion of sitting with back support and forearm support and with a neutral head position in the asymptomatic group. Differences in muscle activity and kinematics were also found between different texting techniques. The differences in texting technique between symptomatic and asymptomatic subjects cannot be explained by them having symptoms but may be a possible contribution to their symptoms. STATEMENT OF RELEVANCE: There has been a dramatically increased use of mobile phones for texting especially among young people during the last years. A better understanding of the physical exposure associated with the intensive use is important in order to prevent the development of musculoskeletal disorders and decreased work ability related to this use. 相似文献
64.
Effect of coumarin and xanthotoxin on mitochondrial structure,oxygen uptake,and succinate dehydrogenase activity in onion root cells 总被引:1,自引:0,他引:1
Ewa Kupidlowska Katarzyna Dobrzynska Eugeniusz Parys Alicja M. Zobel 《Journal of chemical ecology》1994,20(10):2471-2480
At concentrations in which they occur on the plant surface and retard mitosis, coumarin and xanthotoxin lowered uptake of oxygen (by 60 and 30%, respectively) by meristematic cells ofAllium cepa root tips. They caused changes in the structure of the mitochondrial matrix to become dense, and protrusions of mitochondrial membranes were visible parallelling their hypertrophy, indicating alteration in the structure and physiology of these organelles. Coumarin and, to a lesser extent, xanthotoxin increased succinate dehydrogenase production in mitochondria and also in the cytoplasm, indicating changes in membrane permeability. Changes in oxygen uptake and mitochondrial structure, in addition to the retardation of mitosis, may be the reason these compounds act as allelochemicals after they have been removed from the plant surface and reach the root meristem. 相似文献
65.
Calcium Phosphate Materials Prepared from Precipitates with Various Calcium:Phosphorus Molar Ratios 总被引:3,自引:0,他引:3
Anna Alósarczyk Ewa Stobierska Zofia Paszkiewicz Marek Gawlicki 《Journal of the American Ceramic Society》1996,79(10):2539-2544
Depending on the calcium:phosphorus molar ratio of the initial precipitates determined by precipitation conditions (calcium:phosphorus molar ratio of reactants and pH of reaction environment), after sintering at 1250°C, monophase, biphase, or triphase ceramics consisting of hydroxyapatite, β-tricalcium phosphate, α-tricalcium phosphate, and calcium oxide were obtained. The phase composition and properties—i.e., density, shrinkage, hardness, bending strength, and roughness—of the fractured surfaces of the isostatically re-pressed sinters were determined. 相似文献
66.
Ewa Langer Sylwia Waśkiewicz Krzysztof Bortel Marta Lenartowicz-Klik Sebastian Jurczyk 《Iranian Polymer Journal》2017,26(2):115-123
In this study, chemical recycling products of waste poly(ethylene terephthalate) with oligoesters were used as new plasticizers for poly(vinyl chloride) (PVC). The preparation conditions of the dry blend mixtures of the suspension PVC containing synthesised plasticizers were similar to the conditions of the preparing mixtures with commercial plasticizers. The plasticization efficiency of PVC plasticizers was then examined by analysis of the mechanical, physical and chemical properties, as well as the thermal resistance and migration of plasticizer molecules from polymer matrix. Test results proved that compositions with synthesised oligomeric plasticizers possessed similar or better properties than those containing commercial oligomeric plasticizers and much better properties than those having monomeric plasticizers. Thermal stabilities of the proposed plasticizers were higher than those of the commercial plasticizers either monomeric (bis(2-ethylhexyl)phthalate) or oligomeric, despite the fact that the synthesised oligoesters did not contain any antioxidant. The best properties, especially low volatility, very good mechanical properties, low migration were resulted of the transesterification of the waste PET with oligoesters based on adipic acid, triethylene glycol and 2-ethylhexanol which were selected as plasticizers synthesised on the technical scale. The tested plasticized PVC compositions possessed very good tear resistance, tensile strength, decrease of weight loss after 168 h at 80 °C and low migration. Processing properties of PVC compositions containing these synthesised plasticizers confirmed their effectiveness in these compositions for extrusion process. 相似文献
67.
Time dependence of bioactive compounds and antioxidant capacity during germination of different cultivars of broccoli and radish seeds 总被引:2,自引:0,他引:2
Cristina Martinez-Villaluenga Elena Peñas Ewa Ciska Mariusz K. Piskula Halina Kozlowska Concepción Vidal-Valverde Juana Frias 《Food chemistry》2010
Optimisation of the germination process of different cultivars of broccoli (Brassica oleracea var. italica cv. Lucky, cv. Tiburon and cv. Belstar) and radish (Raphanus sativus cv. Rebel and cv. Bolide) seeds in relation to the content of glucosinolates (GLS), vitamin C and total antioxidant capacity was carried out in order to maximise the health-promoting properties of Brassica sprouts. The content of total and individual GLS varied between species, among cultivars, and germination time. Glucoraphanin in broccoli and glucoraphenin in radish were the predominant GLS in raw seeds (61–77 and 63–129 μmol/g DM, respectively) and, although their content decreased during germination, they were maintained in rather large proportions in sprouts. Vitamin C was not detected in raw seeds and its content increased sharply in broccoli and radish sprouts (162–350 and 84–113 mg/100 g DM, respectively). Raw brassica seeds are an excellent source of antioxidant capacity (64–90 and 103–162 μmol Trolox/g DM in broccoli and radish, respectively) and germination led to a sharp increase. Germination of broccoli cv. Belstar and radish cv. Rebel for 4 days provided the largest glucoraphanin and glucoraphenin content, respectively, and also brought about large amounts of vitamin C and antioxidant capacity. 相似文献
68.
Kiran Mariam Wang Cong Papadimitriou George Mandal Anirban Deelman Ewa 《Machine Learning》2020,109(5):1127-1143
Machine Learning - Large-scale scientific workflows rely heavily on high-performance file transfers. These transfers require strict quality parameters such as guaranteed bandwidth, no packet loss... 相似文献
69.
The article describes the influence of the amount and type of organically modified nanosilica (surface and structure modified Aerosil 7200 and surface-modified Aerosil R711) on the photopolymerization kinetics of tetraethylene glycol dimethacrylate and on the physical properties of nanosilica dispersions in the monomer and the polymer matrix. Kinetic measurements showed that silica addition can accelerate or retard the polymerization depending on the silica content; the magnitude of this affect depends on the type of silica modification and can be associated with stability of silica dispersion (as measured by Zeta potential value). The highest reactivity showed compositions containing 4-5 wt.-% of silica and acceleration of the polymerization seems to result mainly from the increase in the propagation rate coefficient. The composites obtained show a uniform dispersion of nanoparticles within the polymer matrix for the silica content at least several wt.-%. The size of aggregates covered with the polymer layer is between 50 and 150 nm for Aerosil R7200 and 75-300 nm for Aerosil R711. 相似文献
70.
Wioletta Florkiewicz Dagmara Malina Klaudia Pluta Karolina Rudnicka Adrian Gajewski Ewa Olejnik Boena Tyliszczak Agnieszka SobczakKupiec 《IET nanobiotechnology / IET》2019,13(7):726
The study was focused on the phytochemicals‐mediated biosynthesis of silver nanoparticles using leaf extracts and infusions from Cynara scolymus. To identify the antioxidant activity and total phenolic content, the 1,1‐diphenyl‐1‐picrylhydrazyl and Folin–Ciocalteau methods were applied, respectively. The formation and stability of the reduced silver ions were monitored by UV–vis spectrophotometer. The particle sizes of the silver nanoparticles were characterised using the dynamic light scattering technique and scanning electron microscope. The phase composition of the obtained silver nanoparticles was characterised by X‐ray diffraction. The silver nanoparticles suspension, artichoke infusion, and silver ions were separately tested towards potential cytotoxicity and pro‐inflammatory effect using mouse fibroblasts and human monocytes cell line, respectively. The total phenolic content and antioxidant activity of ethanol extract and infusion were found significantly higher as compared to aqueous extract and infusion. The UV–visible spectrophotometric analysis revealed the presence of the characteristic absorption band of the Ag nanoparticles. Moreover, it was found that with the increasing volume of plant extract, the average size of particles was increased. Biocompatibility results evidently showed that silver nanoparticles do not induce monocyte activation, however in order to avoid their cytotoxicity suspension at a concentration <2 ppm should be applied.Inspec keywords: pharmaceuticals, health and safety, renewable materials, toxicology, organic compounds, antibacterial activity, X‐ray diffraction, nanomedicine, nanoparticles, nanofabrication, suspensions, ultraviolet spectra, visible spectra, scanning electron microscopy, silver, particle sizeOther keywords: phytochemicals‐mediated biosynthesis, antioxidant activity, total phenolic content, dynamic light scattering technique, silver nanoparticles suspension, scanning electron microscopy, Cynara scolymus, 1,1 diphenyl‐1‐picrylhydrazyl method, cytotoxicity, immune compatibility, leaf extracts, UV‐vis spectrophotometry, particle size, Folin‐Ciocalteau methods, phase composition, X‐ray diffraction, artichoke infusion, pro‐inflammatory effect, mouse fibroblasts, human monocytes cell line, Ag 相似文献