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81.
Functional and nutraceutical foods have captured the global market owing to trends and perceptions of consumers on the natural products and diet-health linkages. Health promoting potential of such foods has been attributed to the presence of essential bioactive moieties. Wheat, being staple food in many parts of the world, gained substantial attention of researchers particularly for the extraction of various functional components. Among these, fructan oligosaccharides in nature bestow quality of baked products and provide protection against various physiological disorders. Addition of fructan in various baked products enhances softness and color, especially in bread, and also imparts textural improvement. Moreover, fructans boost mineral absorption, hypocholesterolemic, and hypoglycemic perspectives, bifidogenic nature and controlling cancer insurgence. The benefits allied with fructan are mainly dose and time dependent. In this context, its industrial applications for vulnerable groups are increasing worldwide.  相似文献   
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83.
A series of blocked diisocyanates has been synthesized from toluene diisocyante (TDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), 4,4′‐diphenylmethane diisocyanate (MDI) and 2‐butoxyethanol. The synthesis of blocked diisocyanate adducts was confirmed by Fourier transform infrared, 1H NMR, electron impact mass spectrometry and nitrogen analysis. Differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and carbon dioxide evolution were used to determine the minimum de‐blocking temperatures. De‐blocking temperatures determined by these three techniques were found to be in the order DSC > TGA > CO2 evolution. The effect of different metal catalysts on thermal de‐blocking reaction of the blocked diisocyanates was studied, using the carbon dioxide evolution method. It was found that iron(III) oxide has the maximum catalytic activity on de‐blocking. The solubility of the blocked diisocyanate adducts was determined in different solvents. The study revealed that at 30 °C blocked IPDI and HDI adducts show better solubility than adducts based on TDI and MDI. Isocyanate‐terminated prepolymers of blocked diisocyanates and hydroxyl‐terminated polybutadiene (HTPB) were prepared. The storage stability and gelation times of the prepolymers were studied. Results showed that all the diisocyanate‐HTPB compositions are stable at 50 °C for more than three months. However, aliphatic diisocyanate‐HTPB compositions require greater gelation time than aromatic diisocyanate‐HTPB compositions at their respective de‐blocking temperatures. Copyright © 2007 Society of Chemical Industry  相似文献   
84.
The authors tested the hypothesis that the cholinergic nucleus basalis magnocellularis (NBM) is involved in solving problems requiring cognitive flexibility. Rats with 192 IgG-saporin lesions of the NBM were assessed for perseveration (i.e., cognitive inflexibility) in the serial reversal of an operant discrimination and during subsequent extinction testing. It was hypothesized that the NBM lesion and control groups would not differ in the acquisition of the initial, simple discrimination, because this task does not demand cognitive flexibility. In contrast, it was hypothesized that the NBM lesion group would show perseveration during serial reversal and extinction testing. Results generally supported these hypotheses, suggesting that the NBM plays an important role in mediating cognitive flexibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
OBJECTIVES: The purpose of this study was to determine the physiologic variables that predict major adverse events in children in the intensive care unit after cardiac operations. METHODS: A cohort observational study was conducted. At the time of admission to the intensive care unit and 4, 8, 12, and 24 hours later the following variables were recorded: mean arterial pressure, heart rate, cardiac index, oxygen delivery, mixed venous oxygen saturation, base deficit, blood lactate, gastric intramucosal pH, carbon dioxide difference (the difference between arterial carbon dioxide tension and gastric intraluminal carbon dioxide tension), and toe-core temperature gradient. Major adverse events were prospectively identified as cardiac arrest, need for emergency chest opening, development of multiple organ failure, and death. RESULTS: Ninety children were included in the study; 12 had major adverse events and there were 4 deaths. Blood lactate level, mean arterial pressure, and duration of cardiopulmonary bypass were the only significant, independent predictors of major adverse events when measured at the time of admission to the intensive care unit. The odds ratio (95% confidence intervals) for major adverse events if a lactate level was greater than 4.5 mmol/L was 5.1 (1.2 to 21.1), for admission hypotension 2.3 (0.5 to 9.8), and for a cardiopulmonary bypass time greater than 150 minutes 13.7 (3.3 to 57.2). Four hours after admission lactate and carbon dioxide difference, and 8 hours after admission lactate and base deficit, were independently significant predictors. The odds ratios for major adverse events if the blood lactate level was greater than 4 mmol/L at 4 and 8 hours were 8.3 (1.8 to 38.4) and 9.3 (1.9 to 44.3), respectively. At no time in the first 24 hours were cardiac output, oxygen delivery, mixed venous oxygen saturation, toe-core temperature gradient, or heart rate significant predictors of major adverse events. CONCLUSIONS: In the context of our current treatment strategies, the duration of cardiopulmonary bypass and blood lactate level, measured in the early postoperative period, were the best predictors of impending major adverse events.  相似文献   
86.
Optimum design of chamfer distance transforms   总被引:4,自引:0,他引:4  
The distance transform has found many applications in image analysis. Chamfer distance transforms are a class of discrete algorithms that offer a good approximation to the desired Euclidean distance transform at a lower computational cost. They can also give integer-valued distances that are more suitable for several digital image processing tasks. The local distances used to compute a chamfer distance transform are selected to minimize an approximation error. A new geometric approach is developed to find optimal local distances. This new approach is easier to visualize than the approaches found in previous work, and can be easily extended to chamfer metrics that use large neighborhoods. A new concept of critical local distances is presented which reduces the computational complexity of the chamfer distance transform without increasing the maximum approximation error.  相似文献   
87.
Six Pakistani wheat cultivars, namely C-273, Inqulab-91, Pasban-90, Parwaz-94, Shahkar-95 and Rohtas-90, were included in the present study. The kernel weight of the wheat cultivars varied from 31.43 to 36.76 g (per thousand kernels), Parwaz-94 having the highest and Rohtas-90 having the lowest. The test weight of cultivars ranged from 70.23 (Shakar-95) to 76.13 kg hL–1 (Pasban-90). The bran contained the highest amount of phytic acid (6.12%) in C-273 followed by whole-wheat flour (2.23%) in Inqulab-91, and straight-grade flour (0.24%) in Parwaz-94. The phytate content was reduced during the baking of bread and chapati. The bread scores and other quality characteristics varied significantly among cultivars. The total bread scores ranged from 35.20 to 42.00, out of a possible fifty, with Parwaz-94 being the highest. The concentration of minerals varied widely in different milling fractions of various wheat cultivars. The concentration of Cu, Fe, Mn and Zn ranged from 5.00 to 52.50, 26 to 147.50, 0.00 to 97.00, 9.0 to 80.80 ppm, respectively, in different milling fractions of the wheat cultivars. The total chapati scores ranged from 22.40 to 24.20 of a possible score of 30. The minimum chapati scores were found in Rohtas-90 and Parwaz-94, while Inqulab-91 produced the maximum score.  相似文献   
88.
Sinusitis is commonly reported in patients with AIDS. In addition to the usual bacterial pathogens isolated from immunocompetent patients, sinusitis in patients with AIDS may be caused by a variety of unusual bacteria, viruses, fungi, parasites, and mycobacteria. Histoplasma capsulatum has not typically been associated with sinusitis in either group of patients. We report a case of sinusitis caused by H. capsulatum in a patient with AIDS.  相似文献   
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90.
The numerical method of construction of axisymmetric slip-line fields is followed to obtain indirect type slip-line field solutions to axisymmetric rod extrusion using some smooth and partially rough conical, cosine, and flat-faced dies. A detailed computer program was written that calculates and plots both the slip-line field and the velocity field and carries out the entire procedure of estimating stresses and velocities in an iterative manner to reach either the desired or a reasonably valid solution, to each of these extrusion problems. The resultant values of the mean extrusion pressures are compared with those given by other authors and with some of the authors own experimental work in rod extrusion (tellurium lead) through conical dies of cone semi-angles, α varying from 11° to 26.5° and at reductions of 36–75%.  相似文献   
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