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41.
A predictive model of the effects of genotypic,pre‐ and postharvest stages on barley β‐glucan levels
BACKGROUND: β‐Glucan is a bioactive component of cereal grains that has many potential uses and health‐promoting benefits. Recent research has focused on improving the nutritional value of food by increasing human exposure to β‐glucan. This study looks at the development of a farm‐level baseline model (including scenario analysis) to evaluate the impact of pre‐ and postharvest stages (including genotypic factors, environmental conditions, agronomic factors and storage) on β‐glucan levels in barley. Monte Carlo simulation techniques were employed to model various stages in pre‐ and postharvest processes and to simulate the factors influencing the level of β‐glucan content in both hulled barley (HB) and hull‐less barley (HLB) genotypes. RESULTS: The baseline model found that the mean simulated level of β‐glucan was 40.99 and 56.77 g kg?1 for HB and HLB genotypes respectively. A sensitivity analysis highlighted that genotype was the most important parameter in determining the final β‐glucan content (correlation coefficients of 0.66 and 0.78 for HB and HLB respectively), more so than any of the agronomic factors analysed. The scenario analysis highlighted the importance of harvest date (scenario 2) and storage conditions (scenario 3), with a potential 32.6 and 32.7% decrease in β‐glucan (compared with the baseline model) if harvesting is carried out early during physiological maturity (i.e. at growth stage 92) and a potential 20.1 and 19.5% increase in β‐glucan for HB and HLB respectively if storage time is minimised. CONCLUSION: This study predicted the influence of genotypic, pre‐ and postharvest operations on β‐glucan content and thus allows strategies to be identified to influence β‐glucan content in barley products. Copyright © 2008 Society of Chemical Industry 相似文献
42.
The present work discusses the combined effect of High Density Polyethylene Homo polymer and Styrene-Butadiene-Styrene on properties of Viscosity Grade 30 asphalt commonly used in India. Six blends of binders were prepared using varying percentages of both polymers and were evaluated for rheological properties. Use of both polymers leads to higher viscosity, while blending with HDPH polymer only leads to marginal increase in viscosity when compared to unmodified binder. Comparison of dynamic modulus and phase angle master curves indicated, significant differences were found among master curves obtained with different aging conditions when compared to unaged condition especially at lower reduced frequencies. 相似文献
43.
Natural convection heat transfer in a square cavity (with wavy or plane wall) filled with non-Newtonian power-law nanofluid has been elucidated for several input parameters like Ra spanning from 105 to 106, power-law index (n) from 0.6 to 1.4, and volume fraction of CuO nanoparticles (?) from to 0 to 0.12. Effect of external magnetic field on heat transfer has been illustrated by varying the Ha from 0 to 90. In the present study, our main objective is to explore the effect of nanoparticles on heat transfer enhancement in non-Newtonian power-law fluid. It is found that the addition of nanoparticles (?) to shear thinning fluid enhances the heat transfer approximately 15% when ? increases from 0 to 0.12 for Ha less than 60 at all Ra. For a shear thickening fluid, the same thing happens for all Ha at any Ra. The average surface Nusselt number for a cavity with wavy wall is less than that of a plane wall for all cases which is not true for the case of local Nusselt number. 相似文献
44.
The role of natural antioxidants in combating the deleterious effects of free radicals has received much attention. In the present study, the cytoprotective effects and the free radical scavenging activity of geraniin, a hydrolysable ellagitannin from Nephelium lappaceum rind, were evaluated by using various approaches. Addition of geraniin to the culture media resulted in a profound cytoprotective effect against damages induced by the peroxynitrite generator 3-morpholinosydnonimine (SIN-1), and the peroxyl radical generator 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH). Geraniin exhibits more potent cytoprotective activity than that of 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox). Geraniin exhibited potent antioxidant activity against reactive species, such as nitric oxide, superoxide anion, and chemically synthesized peroxynitrite. Kinetic analysis of reactivity against peroxyl radicals generated by AAPH revealed that geraniin possesses potent reactivity against peroxyl radicals with higher stoichiometric number than Trolox. The cytoprotective effect of geraniin was only observed when geraniin and these toxic compounds were co-existing, suggesting that geraninn exhibits cytoprotective effects via free radical scavenging activity in the extracellular fluid. 相似文献
45.
Akila Swaminathan Sree Rama Chaitanya Sridhara Swaraj Sinha Shunmugam Nagarajan Uma Maheswari Balaguru Jamila H Siamwala Saranya Rajendran Uttara Saran Suvro Chatterjee 《Journal of food science》2012,77(12):H273-H279
Abstract: Recent evidence has demonstrated that nitrites play an important role in the cardiovascular system. Fennel (Foneiculum vulgare) seeds are often used as mouth fresheners after a meal in both the Indian sub‐continent and around the world. The present study aims to quantify the nitrite and nitrates in fennel seeds as well as elucidating the effect of fennel derived‐nitrites on vascular functions. Results from our study show that fennel seeds contain significantly higher amount of nitrites when compared to other commonly used post‐meal seeds. Furthermore our study confirmed the functional effects of fennel derived‐nitrites using in vitro and ex vivo models that describe the promotion of angiogenesis, cell migration, and vasorelaxation. We also showed that chewing fennel seeds enhanced nitrite content of saliva. Thus our study indicates the potential role of fennel derived‐nitrites on the vascular system. Practical Application: This study is focused on determining the effect of fennel‐derived nitrites on angiogenesis (the formation of new blood vessels from pre‐existing ones), cell migration, and vasorelaxation (dilation of blood vessels) thereby preserving cardiovascular health. 相似文献
46.
Discretization: An Enabling Technique 总被引:26,自引:0,他引:26
47.
Studies on the decomposition of α-primary hydroperoxide of secondary butyltoluene in alkaline medium
Girendra N. Kulsrestha Uma Shanker Jaipal S. Sharma 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1984,34(3):103-106
α-Primary hydroperoxides of s-butyltoluene (SBT) are preferentially decomposed when the hydroperoxide concentrate is treated with 2 M aqueous sodium hydroxide at 70°C. The decomposition is complete in 1 h. The rate of decomposition and the nature of products formed suggest the reaction to be first order with respect to the primary-hydroperoxide concentration in accord with the Kornblum-De La Mare mechanism. Salt formation of the hydroperoxide precedes the decomposition. 相似文献
48.
J. G. Dash 《Journal of Low Temperature Physics》1969,1(3):173-188
Heat capacities of adsorbed monolayers of He3and He4indicate that the dominant thermal excitations at low temperatures are phonons rather than single-particle modes when the films are near maximum density. A recent theoretical study of noninteracting particles adsorbed on a crystalline substrate yielded a two-dimensional band structure, and explored the thermodynamic properties of the single-particle modes. The theory is now extended to include the influence of hard-core interactions between the particles moving in the lowest band. Resembling the high-density approximations for liquid and solid helium, the hard-core interactions are shown to give rise to a collective zero-point kinetic energy from which a two-dimensional pressure and a compressibility are derived. The corresponding velocity of sound and phonon heat capacity are calculated in the weak-binding and tight-binding approximations. Comparison with experiment indicates that the weak-binding approximation is more appropriate and that it yields effective mass ratiosm*/m1.7 for the two isotopes at the experimental film densities. A novel feature of the tight-binding calculation that may be applicable to other experimental systems is the prediction of phase condensation for adsorbed gases of relatively small molecular diameter.Research supported by the National Science Foundation. 相似文献
49.
Industry case studies in the use of immersive virtual assembly 总被引:1,自引:0,他引:1
Sankar Jayaram Uma Jayaram Young Jun Kim Charles DeChenne Kevin W. Lyons Craig Palmer Tatsuki Mitsui 《Virtual Reality》2007,11(4):217-228
In this paper, we report on two engineering case studies that have been conducted as part of a Virtual Assembly Technology
Consortium. The objectives of the case studies were to determine if immersive virtual assembly capabilities allow industry
assembly situations to be modelled and studied realistically, and to demonstrate the downstream value of the virtual assembly
capabilities in areas such as ergonomics, assembly installation, process planning, installation, and serviceability. What
is of special significance is that instead of modelling simplified problems or perceived representative situations, the case
studies were constructed from actual assembly floor projects and situations encountered at industry member sites and with
considerable participation from industry engineers and manufacturing shop floor personnel. Based on the success of the case
studies, the consortium members inferred that virtual assembly methods are poised to move out of the realm of special projects
and test scenarios to deployment in the actual design and manufacturing cycle. However, in order to be truly accepted in industry,
there are still issues to be addressed in terms of ease of use, portability of the applications, and preparation of the models
for the evaluations. Thus, the case studies added a new dimension to the exploration and understanding of how this new technology
could be of practical value in industry. 相似文献
50.
Zexuan Zhu Yew-Soon Ong Manoranjan Dash 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(1):70-76
This correspondence presents a novel hybrid wrapper and filter feature selection algorithm for a classification problem using a memetic framework. It incorporates a filter ranking method in the traditional genetic algorithm to improve classification performance and accelerate the search in identifying the core feature subsets. Particularly, the method adds or deletes a feature from a candidate feature subset based on the univariate feature ranking information. This empirical study on commonly used data sets from the University of California, Irvine repository and microarray data sets shows that the proposed method outperforms existing methods in terms of classification accuracy, number of selected features, and computational efficiency. Furthermore, we investigate several major issues of memetic algorithm (MA) to identify a good balance between local search and genetic search so as to maximize search quality and efficiency in the hybrid filter and wrapper MA 相似文献