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971.
The effect of hydration level on processing properties and the effects of hydration level, concentration of buckwheat bran flour and drying temperature on the physical and cooking quality of spaghetti were determined. Specific mechanical energy transferred to the dough during extrusion decreased 69% for semolina and 79% for semolina containing 30%, w/w, buckwheat bran flour, as hydration level increased 29–32% absorption. Little or no postdrier checking occurred in spaghetti made from semolina or spaghetti containing buckwheat bran flour when dried at high (70°C) or ultrahigh temperature (90°C). When dried at low temperature (40°C), tolerance to postdrier checking of spaghetti decreased as buckwheat bran flour increased 0–30% (w/w). Hydration level before extrusion did not affect cooking loss of spaghetti made from semolina. However, cooking loss was greater from spaghetti made with semolinabuckwheat bran flour that was hydrated to 32% compared with 29–31% absorption. Cooked firmness of spaghetti containing buckwheat bran flour decreased from 0.588–0.471 Nm as hydration increased from 29–32% absorption. Cooking loss was lower and cooked firmness was greater when spaghetti containing buckwheat bran flour was dried at ultrahigh than at low temperature.  相似文献   
972.
The genetic structure of 276 Sclerotinia sclerotiorum isolates representing 37 field populations from four provinces in northern Iran were analysed with six polymorphic microsatellite loci. In total, 80 haplotypes were detected with 19 haplotypes (23.7%) shared amongst at least two regional populations. None of the haplotypes were shared among all four regional populations. Of the 80 haplotypes, 32 haplotypes (40%) occurred in low frequencies represented by only one isolate. Moderate levels of gene diversity (H = 0.51 to 0.61) and genotypic diversity (Ĝ = 12.0 to 22.0; clonal fraction = 0.39 to 0.67) for regional populations were observed. Genotypic diversities (Ĝ) did not differ significantly among populations. All regional populations were in linkage equilibrium indicating the occurrence of outcrossing. Low to moderate levels of population subdivision (0.03 to 0.07), were observed among regional populations. Only one large panmictic population was inferred by Structure, indicating no significant population structure. A Mantel test showed no significant isolation by distance (r = −0.43; P = 0.18), indicating anthropogenic movement of inoculum. The results demonstrated that S. sclerotiorum populations in northern Iran, are randomly mating and have a number of shared haplotypes among regional populations; this possibly represents recent founder populations and/or a high occurrence of anthropogenic migration of infected plant material among populations.  相似文献   
973.
The present study aimed at examining the amenability of Stereospermum suaveolens DC. to vegetative propagation through rooting of leafy stem cuttings using low-cost polythene propagators. Rooting efficiencies of cuttings derived from two selected matured mother trees were studied using four different concentrations of Indole-3-butyric acid (IBA), viz. 0, 0.1, 0.2 and 0.4%. IBA applied at 40 μg per cutting (0.4% concentration) resulted in significantly higher rooting responses compared to the control (< 0.05). Differences in the length of longest root for all the treatments were significant (P = 0.05) with cuttings treated with 0.2% IBA producing the longest root. The highest survival after 3 weeks of transference of the rooted cuttings into polythene bags was found for rooted cuttings treated with 0.2% IBA. Effects of three fertilizer treatments viz. T0 (no fertilizer), T1 (10 g of Urea + 20 g of TSP + 10 g of MOP dissolved in 1 l of water) and T2 (10 g of Urea + 20 g of TSP + 10 g of MOP dissolved in 2 l of water) on initial growth of established rooted cuttings (stecklings) of Stereospermum suaveolens in polythene bags were also measured for a period of 90 days. Stem length, collar diameter and leaf area of the stecklings increased throughout the observation period. Increments of both stem length and collar diameter were significantly higher for the stecklings treated with T2 in comparison with the control while increment of leaf area was found the highest for the stecklings treated with T1. The study clearly indicated that Stereospermum suaveolens is amenable to vegetative propagation technique using juvenile single-node leafy cuttings and the initial growth performance of the established rooted cuttings (stecklings) in polythene bags under different fertilizer treatments was satisfactory.  相似文献   
974.
Ultra fine fibers were electrospun from regenerated silk fibroin/formic acid solution. Effect of some process parameters on the morphology, diameter and variation in fiber diameter of electrospun fibers were experimentally investigated. Scanning electron microscope was used for the measurement of fiber diameter. Fibers with diameter ranging from 80 to 210 nm were collected depending on the solution concentration and the applied voltages. Response surface methodology (RSM) was used to obtain a quantitative relationship between selected electrospinning parameters and the average fiber diameters and its distribution. It was shown that concentration of silk fibroin solution had a significant effect on the fiber diameter and the standard deviation of the fiber diameter. Applied voltage had no significant effect on the fiber diameter and its standard deviation.  相似文献   
975.
Modern biotechnology,based on recombinant DNA techniques,has made it possible to introduce new traits with great potential for crop improvement.However,concerns about unintended effects of gene transformation that possibly threaten environment or consumer health have persuaded scientists to set up pre-release tests on genetically modified organisms.Assessment of‘substantial equivalence’concept that established by comparison of genetically modified organism with a comparator with a history of safe use could ...  相似文献   
976.
Chemical industry project management involves complex decision making situations that require discerning abilities and methods to make sound decisions. Chemical engineers as project managers are faced with decision environments and problems in chemical industry projects that are complex. Multiple-criteria decision making (MCDM) approaches are major parts of decision theory and analysis. This paper presents all of MCDM approaches for use in chemical engineering management decisions. In this work, case study is Research and Development (R&D) project selection in chemical industry. The ability to make sound decisions is very important to success of R&D projects. It is hoped that this work will provide a ready reference on MCDM and this will encourage the application of the MCDM in chemical engineering management.  相似文献   
977.
This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.  相似文献   
978.
This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one.The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.  相似文献   
979.
An 8‐week feeding trial was conducted to evaluate the effects of dietary probiotics on growth, non‐specific immune responses and disease resistance in juvenile rainbow trout, Oncorhynchus mykiss. Fish averaging 5.8 ± 0.8 g (mean ± SD) were fed one of the five experimental diets; one control (Cont), and four other diets were prepared by supplementing single probiotics 1 (Bacillus subtilis; SP1, 0.5%), single probiotics 2 (Bacillus licheniformis; SP2, 0.5%), multi‐probiotics (B. subtilis + B. licheniformis; MP, 0.5%) and oxytetracycline (OTC) at 5 g OTC kg?1 diet. After 8 weeks of the feeding trial, weight gain and specific growth rate of fish fed SP1, SP2 and OTC diets were significantly higher than those of fish fed Cont diet (P < 0.05). Superoxide dismutase (SOD) and lysozyme activities of fish fed SP1, SP2 and MP diets were significantly higher than those of fish fed Cont diet (P < 0.05). There were no significant differences in SOD and lysozyme activities among fish fed SP1, SP2, MP and OTC diets. In challenge test with Aeromonas salmonicida for 15 days, fish fed SP1, SP2 and MP diets showed significantly higher cumulative survival rate than those of fish fed Cont diet (P < 0.05). However, there were no significant differences in cumulative survival rate among fish fed SP1, SP2, MP and OTC diets. Although there was a little advantage in fish fed MP diet in terms of non‐specific immune responses, single or multi‐probiotics are equally effective statistically. These results indicate that single or multi‐probiotics had equal beneficial effects as an antibiotic replacer on growth performance, non‐specific immune responses and disease resistance in juvenile rainbow trout.  相似文献   
980.
A feeding experiment was conducted in a closed recirculating system to evaluate the effects of freeze‐dried spheroplasts prepared from Pyropia yezoensis (Ueda) on feed intake, growth and biochemical composition of sea cucumber, Apostichopus japonicus (Selenka). Pyropea spheroplasts (PS) were prepared through enzymatic treatment to break down the complex mixture of polysaccharides cell walls that might be easier for growth energy partitioning. Sea cucumbers were fed‐formulated diets with 10 (Diet 1), 30 (Diet 2) and 50 g/kg (Diet 3) inclusion level of PS. A diet without PS was used as a control (Diet 4). The experiment was conducted for 6 weeks maintaining water temperature 15 ± 1°C, photoperiod 18:06 hours (D:L). Feed was supplied ad‐libitum at 16.00 h once in a day, and the remaining feed and faeces were removed in the next day. Results showed that the highest growth was observed in the 50 g/kg PS diet compared to other treatments. Total weight gain, mean weight gain, net yield, protein efficiency ratio (PER) and protein gain (%) were significantly higher in the 50 g/kg PS diet (p < .05). A significantly higher percentage of energy was allocated for growth in the 50 g/kg PS diet. The highest specific growth rate and feed conversion efficiency (p < .05) were observed in the higher percentage of PS diet. Both the growth performance and biochemical analysis showed that superior growth was observed with increasing levels of PS in the diet. We infer that PS can be used as a new, cheaper feed ingredient in the formulated diet of A. japonicus.  相似文献   
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