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131.
Milena
ciskalska Monika Odakowska Halina Milnerowicz 《International journal of molecular sciences》2021,22(11)
This study was aimed at evaluating the changes in metallothionein (MT) concentration in the blood of patients with acute pancreatitis (AP) and healthy subjects, taking into account the extracellular (plasma) and intracellular (erythrocyte lysate) compartments. The impact of single-nucleotide polymorphisms (SNPs) in the MT1A (rs11640851), MT1B (rs964372) and MT2A (rs10636) genes on MT concentration and their association with the concentration of metals (Cu, Zn, Cd) and ceruloplasmin as Cu-related proteins were analyzed. The concentration of a high-sensitivity C-reactive protein (hs-CRP) and IL-6 as markers of inflammation, and malonyldialdehyde (MDA), superoxide dismutase (SODs) activity and the value of total antioxidant capacity (TAC) as parameters describing the pro/antioxidative balance were also assessed. In the AP patient groups, an increased MT concentration in erythrocyte lysate compared to healthy subjects was shown, especially in individuals with the GG genotype for rs964372 in the MT1B gene. A Zn concentration was especially decreased in the blood of smoking AP patients with the AA genotype for SNP rs11640851 in the MT1A gene and the GC genotype for SNP rs10636 in MT2A, compared to non-smokers with AP, which was accompanied by an increase in the value of the Cu/Zn ratio. The exposure to tobacco smoke xenobiotics increased the risk of AP occurrence in subjects with the CC genotype for SNP rs11640851 in the MT1A gene by more than fourfold. The investigated polymorphisms, rs11640851 in the MT1A gene, rs964372 in the MT1B gene and rs10636 in the MT2A gene, seem to be an important factor in maintaining homeostasis in an organism under oxidative stress conditions. 相似文献
132.
Dianne Cyr Milena Head Hector Larios 《International journal of human-computer studies》2010,68(1-2):1-21
Colour has the potential to elicit emotions or behaviors, yet there is little research in which colour treatments in website design are systematically tested. Little is known about how colour affects trust or satisfaction on the part of the viewer. Although the Internet is increasingly global, few systematic studies have been undertaken in which the impact of colour on culturally diverse viewers is investigated in website design. In this research three website colour treatments are tested across three culturally distinct viewer groups for their impact on user trust, satisfaction, and e-loyalty. To gather data, a rich multi-method approach is used including eye-tracking, a survey, and interviews. Results reveal that website colour appeal is a significant determinant for website trust and satisfaction with differences noted across cultures. The findings have practical value for web marketers and interface designers concerning effective colour use in website development. 相似文献
133.
The paper shows that nonlinear retarded time-delay systems can admit an input–output representation of neutral type. This behaviour represents a strictly nonlinear phenomenon, for it cannot happen in the linear time-delay case where retarded systems always admit an input–output representation of retarded type. A necessary and sufficient condition for a nonlinear system to exhibit this behaviour is given, and a strategy for finding an input–output representation of retarded type is outlined. Some open problems that arise consequently are discussed as well. All the systems considered in this work are time-invariant and have commensurable delays. 相似文献
134.
Patrícia Anacleto Ana Luísa Maulvault Milena Chaguri Sónia Pedro Maria Leonor Nunes Rui Rosa António Marques 《Food microbiology》2013
The microbiological responses of two bivalves species from Tagus estuary, Venerupis pullastra (native clam) and Ruditapes philippinarum (exotic clam) were investigated during 48 h of depuration and subsequent simulated transport in semi-dry conditions at two temperatures (4 and 22 °C) until reaching 50% lethal time (LT50). Regardless of temperature and species, the maintenance of clams in water for 48 h (depuration period) did not affect LT50 during transport. R. philippinarum showed higher survival rates than V. pullastra, always reaching LT50 later, especially at 4 °C. Significant differences between clams' species were found in almost all microbiological parameters. This can be related with clams' biological activity and habitat environmental conditions since both clams do not coexist in Tagus estuary. Depuration was efficient to reduce the bacterial load, particularly Escherichia coli, but not efficient to remove Vibrio spp. In both species, the growth of Vibrio spp. was inhibited at 4 °C, whereas exponential growth occurred at 22 °C. Total viable counts significantly increased in most treatments, while E. coli counts significantly decreased to undetected levels, except for non-depurated R. philippinarum simulated transported at 4 °C. Thus, this study highlights the importance of clams depuration for at least 24 h in polluted estuarine areas, followed by transport at low temperatures (4 °C). 相似文献
135.
136.
Unmodified and esterified Kraft lignin‐filled polyethylene composites: Compatibilization by free‐radical grafting
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In this study, the effectiveness of free‐radical grafting as a compatibilization method applied to composites containing Kraft lignin (KL) and esterified lignin was comparatively investigated. Maleated lignin (ML) was first obtained via esterification of KL with maleic anhydride. KL and ML were respectively incorporated into high density polyethylene (HDPE) up to 60% wt and dicumyl peroxide was used as a free‐radical generator. The influence of lignin esterification and free‐radical grafting on the morphological, mechanical, and thermal properties of lignin‐based composites was studied. The incorporation of lignins into HDPE resulted in poor mechanical strength because of low compatibility. Morphological and mechanical evidences indicate improved compatibility between lignins and HDPE following free‐radical grafting. The free‐radical scavenging properties of KL allowed better compatibilization of KL‐based composites compared with ML‐based composites. In addition, thermal analysis results showed that free‐radical grafting increases the thermal stability of ML‐based composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41484. 相似文献
137.
Vladimir Komanicky Andi Barbour Miroslava Lackova Milena Zorko Chenhui Zhu Michael Pierce Hoydoo You 《Nanoscale research letters》2014,9(1):336
We developed a method for production of arrays of platinum nanocrystals of controlled size and shape using templates from ordered silica bead monolayers. Silica beads with nominal sizes of 150 and 450 nm were self-assembled into monolayers over strontium titanate single crystal substrates. The monolayers were used as shadow masks for platinum metal deposition on the substrate using the three-step evaporation technique. Produced arrays of epitaxial platinum islands were transformed into nanocrystals by annealing in a quartz tube in nitrogen flow. The shape of particles is determined by the substrate crystallography, while the size of the particles and their spacing are controlled by the size of the silica beads in the monolayer mask. As a proof of concept, arrays of platinum nanocrystals of cubooctahedral shape were prepared on (100) strontium titanate substrates. The nanocrystal arrays were characterized by atomic force microscopy, scanning electron microscopy, and synchrotron X-ray diffraction techniques. 相似文献
138.
Guenat OT Generelli S de Rooij NF Koudelka-Hep M Berthiaume F Yarmush ML 《Analytical chemistry》2006,78(21):7453-7460
In this study, we present the development and the characterization of a generic platform for cell culture able to monitor extracellular ionic activities (K+, NH4+) for real-time monitoring of cell-based responses, such as necrosis, apoptosis, or differentiation. The platform for cell culture is equipped with an array of 16 silicon nitride micropipet-based ion-selective microelectrodes with a diameter of either 2 or 6 microm. This array is located at the bottom of a 200-microm-wide and 350-microm-deep microwell where the cells are cultured. The characterization of the ion-selective microelectrode arrays in different standard and physiological solutions is presented. Near-Nernstian slopes were obtained for potassium- (58.6 +/- 0.8 mV/pK, n = 15) and ammonium-selective microelectrodes (59.4 +/- 3.9 mV/pNH4, n = 13). The calibration curves were highly reproducible and showed an average drift of 4.4 +/- 2.3 mV/h (n = 10). Long-term behavior and response after immersion in physiological solutions are also presented. The lifetime of the sensors was found to be extremely long with a high recovery rate. 相似文献
139.
A method to amplify the rotation angle of a mirror, based on multiple reflections between two quasi-parallel mirrors, is presented. The method allows rotations of fractions of nanoradians to be measured with a simple setup. The working principle, the experimental setup, and the results are presented. 相似文献
140.
Esparto (Stipa tenacissima) grass, also called Alfa is the raw material for the manufacture of paper pulp in North Africa. To add value to one of its processing by‐products, we aimed to develop lubricants from modified Soda‐Lignin (SL), which could eventually compete with industrial lubricants such as zinc stearates. Linear low density polyethylene mixed formulations prepared with zinc stearate and each modified lignin was studied by rheological tests using a rotational parallel plate system to investigate the effects of such esterified SL additives. One type, made up of SL esterified with 100% stearic anhydride (W/W) was found to promote excellent external lubrication. The same result was confirmed by contact angle and thermal analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献