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101.
We have made surface plasmon resonance (SPR) measurements of yeast iso-1-cytochrome c (Cyt c) on a gold surface. Angle-resolved SPR curves are recorded as a function of urea concentration before and after self-assembly of the Cyt c. Exposure to a urea solution causes denaturation of Cyt c, which shifts the minimum in the SPR curve to a larger angle and decreases the signal amplitude. The Gibbs free energy change for denaturation of the protein on Au is calculated from the change of the SPR signal amplitude with urea concentration. We find that (1) Cyt c can be reversibly denatured and renatured, depending on the urea concentration, and (2) the Gibbs free energy change for denaturation of Cyt c on Au surface in water, DeltaG degrees (water), is 1.5 kcal/mol, which is approximately 4 times less than that in bulk solution. 相似文献
102.
?zgül Ger?el Adnan ?zcan A. Safa ?zcan H. Ferdi Ger?el 《Canadian Metallurgical Quarterly》2009,135(5):333-340
The present research deals with the production of activated carbon by chemical activation using peach stones and its adsorption behavior. The prepared activated carbon was used for the adsorption of three kinds of textile dyes, acid, reactive, and direct dyes, from aqueous solution. The results indicated that the overall adsorption process followed the pseudo-second-order kinetic model. The equilibrium data were found to be well represented by the Langmuir adsorption isotherm model. The calculated adsorption capacities for Reactive Orange 16, Acid Yellow 11, and Direct Red 23 onto activated carbon were 667, 539, and 427?mg?g?1 at 50°C, respectively. Thermodynamic parameters, such as ΔG°, ΔH°, and ΔS°, were also calculated and indicated that the adsorption of dyes onto activated carbon was spontaneous and endothermic in nature. 相似文献
103.
Bregje Van De Wier Ger H. Koek Aalt Bast Guido R. M. M. Haenen 《Critical reviews in food science and nutrition》2017,57(4):834-855
The contemporary pathophysiological model of non-alcoholic fatty liver disease (NAFLD) comprises multiple parallel pathways with a dynamic cross talk that cumulate in steatosis and inflammation, and ultimately fibrosis, cirrhosis, liver failure, and hepatocellular carcinoma. So far, no pharmacological treatment has been approved. A major impediment of drugs, in general, is that they are intended to act on one single target in the pathology of a disease. However, the multitude of pathways involved in the pathogenesis of NAFLD underpins the need for treatments that address these various pathways. Interestingly, flavonoids have been found to have positive effects on lipid metabolism, insulin resistance, inflammation, and oxidative stress, the most important pathophysiological pathways in NAFLD. This puts flavonoids in the spotlight for the treatment of NAFLD and prompted us to review the existing evidence for the use of these food-derived compounds in the treatment of NAFLD. 相似文献
104.
Hüseyin Boz Mehmet Murat Karaoğlu Halis Gürbüz Kotancilar Kamil Emre Gerçekaslan 《International Journal of Food Science & Technology》2010,45(7):1472-1477
In this research, the effects of different materials such as defatted Cephalaria syriaca flour (0.5%), rosehip (2.5%), vital gluten (2.5%) and malt flour (2%), and their combinations on the quality of organic whole wheat flour were investigated. The highest maximum resistance value was obtained in the treatment containing 0.5% cephalaria and 2.5% rosehip. The addition of malt flour and vital gluten significantly increased the extensibility value. Although rosehip, cephalaria and vital gluten generally increased the dough energy, malt flour decreased the dough energy when compared to the control. The combination of 0.5% cephalaria and 2.5% rosehip significantly decreased the adhesion and stringiness of dough. Data showed that dough rheological characteristics of organic whole wheat flour could be improved with the addition of different materials such as malt flour, cephalaria, rosehip and vital gluten. 相似文献
105.
In this study, a fiber-blowing process was utilized to prepare mineral fibers from water-quenched slags to raise the additional value of the recycled slag. Based on their excellent physical and thermal properties, slag fibers were added into a phenol–formaldehyde matrix followed by thermal curing to produce slag fiber-based composites. The friction and wear tests were applied to evaluate the tribological performance of the slag fiber-based composites. Although the optimum process parameters are still under investigation, however, it appeared that slag fiber prepared by this study shows its potential for use in frictional composites based on our results. 相似文献
106.
Influence of Hymenaea courbaril gum as a new additive on nixtamalized flour properties and quality of tortilla 下载免费PDF全文
107.
Nemi Malhotra Kelvin H.-C. Chen Jong-Chin Huang Hong-Thih Lai Boontida Uapipatanakul Marri Jmelou M. Roldan Allan Patrick G. Macabeo Tzong-Rong Ger Chung-Der Hsiao 《International journal of molecular sciences》2021,22(17)
In this paper, we review the effects of large-scale neonicotinoid contaminations in the aquatic environment on non-target aquatic invertebrate and vertebrate species. These aquatic species are the fauna widely exposed to environmental changes and chemical accumulation in bodies of water. Neonicotinoids are insecticides that target the nicotinic type acetylcholine receptors (nAChRs) in the central nervous systems (CNS) and are considered selective neurotoxins for insects. However, studies on their physiologic impacts and interactions with non-target species are limited. In researches dedicated to exploring physiologic and toxic outcomes of neonicotinoids, studies relating to the effects on vertebrate species represent a minority case compared to invertebrate species. For aquatic species, the known effects of neonicotinoids are described in the level of organismal, behavioral, genetic and physiologic toxicities. Toxicological studies were reported based on the environment of bodies of water, temperature, salinity and several other factors. There exists a knowledge gap on the relationship between toxicity outcomes to regulatory risk valuation. It has been a general observation among studies that neonicotinoid insecticides demonstrate significant toxicity to an extensive variety of invertebrates. Comprehensive analysis of data points to a generalization that field-realistic and laboratory exposures could result in different or non-comparable results in some cases. Aquatic invertebrates perform important roles in balancing a healthy ecosystem, thus rapid screening strategies are necessary to verify physiologic and toxicological impacts. So far, much of the studies describing field tests on non-target species are inadequate and in many cases, obsolete. Considering the current literature, this review addresses important information gaps relating to the impacts of neonicotinoids on the environment and spring forward policies, avoiding adverse biological and ecological effects on a range of non-target aquatic species which might further impair the whole of the aquatic ecological web. 相似文献
108.
An algorithm using the unsupervised Bayesian online learning process is proposed for the segmentation of object-based video images. The video image segmentation is solved using a classification method. First, different visual features (the spatial location, colour and optical-flow vectors) are fused in a probability framework for image pixel clustering. The appropriate modelling of the probability distribution function (PDF) for each feature-cluster is obtained through a Gaussian distribution. The image pixel is then assigned a cluster number in a maximum a posteriori probability framework. Different from the previous segmentation methods, the unsupervised Bayesian online learning algorithm has been developed to understand a cluster's PDF parameters through the image sequence. This online learning process uses the pixels of the previous clustered image and information from the feature-cluster to update the PDF parameters for segmentation of the current image. The unsupervised Bayesian online learning algorithm has shown satisfactory experimental results on different video sequences. 相似文献
109.
The present work integrates the multiscale transform provided by the wavelets and singular value decomposition (SVD) for the detection of anomaly in self-similar network data. The algorithm proposed in this paper uses the properties of singular value decomposition (SVD) of a matrix whose elements are local energies of wavelet coefficients at different scales. Unlike existing techniques, our method determines both the presence (i.e., the time intervals in which anomaly occurs) and the nature of anomaly (i.e., anomaly of bursty type, long or short duration, etc.) in network data. It uses the diagonal, left and right singular matrices obtained in SVD to determine the number of scales of self-similarity, location and scales of anomaly in data, respectively. Our simulation work on different data sets demonstrates that the method performs better than the existing anomaly detection methods proposed for self-similar data. 相似文献
110.
The heavy- and light-chain variable regions from a murine monoclonal antibody that recognize Pseudomonas aeruginosa serogroup O6 lipopolysaccharide (LPS) were used to generate a series of chimeric mouse-human monoclonal antibodies with identical variable regions. The murine variable-region gene segments were cloned into an immunoglobulin (Ig) cDNA expression vector that contained the human kappa light-chain and IgG1 constant regions. The IgG1 heavy-chain constant region was then replaced with the human IgG2, IgG3, IgG4, or IgA1 heavy-chain constant region. The five different expression vectors were transfected into Chinese hamster ovary cells for antibody production. The chimeric antibodies exhibited immunoreactivity and affinity similar to that of the parental murine IgG antibody toward whole cells of a serogroup O6 strain. In vitro complement deposition assays demonstrated that the chimeric IgG4 and IgA antibodies did not mediate the deposition of complement component C3 onto the surface of either purified LPS or whole bacteria. The chimeric IgG1 and IgG3 antibodies were similar in their ability to deposit C3 onto the surface of both bacteria and LPS, while IgG2 antibody was more effective at depositing C3 onto the surface of bacteria than onto purified LPS. The pattern of opsonophagocytic activity of the chimeric monoclonal antibodies was similar to that of complement deposition onto bacterial cells in that the chimeric IgG1 and IgG3 had the highest opsonic activity. Although IgG2 deposited more C3 onto the bacterial surface than did IgG4 or IgA, all three of these isotypes had low opsonic activity against the serogroup O6 target strain. This series of related antibodies will help reveal functional differences in efficacy among protective antibodies to P. aeruginosa and will be critical for defining the optimal formulation of either a vaccine for active immunization or a polyclonal intravenous IgG or monoclonal antibody cocktail for passive immunotherapy. 相似文献