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11.
A total of 147 simple sequence repeat (SSR) markers (including86 barley and 61 wheat microsatellite markers) were tested for their segregation in a doubled haploid (DH) and an F2 population of barley. The DH population consisted of 71 doubled haploid lines, developed from F1 plants of a cross between Tadmor and WI2291using isolated microspore culture technique. A genetic linkage map consisting of 43 microsatellite markers was constructed using the DH population. Particularly on chromosome 4H microsatellite markers showed distorted segregation ratios. Segregation of DH lines based on molecular markers were compared with segregation of 92 F2 lines from the same cross. The proportion of loci deviating from the expected monogenic segregation ratios in the DH population was significantly higher (19/43loci, 44%) than in the F2 population (7/43 loci, 16%). The deviation was biased towards the WI2291 parent alleles. In line with this observation, WI2291 was found to perform better than Tadmor in regenerating green plantlets with the isolated microspore-culture technique. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
12.
In order to identify antigens that can help prevent camel tick infestations, three major glycoproteins (GLPs) about 97, 66 and 40 kDa in size were purified from adult and larval Egyptian ticks, Hyalomma (H.) dromedarii, using a single-step purification method with Con-A sepharose. The purified GLPs were evaluated as vaccines against camel tick infestation in rabbits. The rabbits received three intramuscular inoculations of GLPs (20 µg/animal) on days 0, 14, and 28. In the immunoblot analysis, Sera from the immunized rabbits recognized the native GLPs and other proteins from larval and adult H. dromedarii ticks along with those from other tick species such as Rhipicephalus sanguineus but not Ornithodoros moubata. The effects of immunity induced by these GLPs were determined by exposing rabbits to adult H. dromedarii ticks. These results demonstrated that GLP immunization led to a slightly decreased reproductive index and significantly reduced rates of egg hatchability. These results demonstrated that immunization with the purified GLPs can provide protection against infestation by H. dromedarii and some other tick species. Further studies are needed to confirm the effectiveness of immunization with GLPs against other tick species.  相似文献   
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14.
This study investigated the effects of Jujube (Ziziphus jujube) fruit extract (JFE) as an excellent source of nutrients and phytochemicals on the innate immune responses and expression of genes involved in intestinal immunity of common carp (Cyprinus carpio) fingerlings. Three hundred healthy carps (10.78 ± 0.05 g) fingerlings were randomly allocated to 12 fibre glass tanks (300L; 15 fish per tank) and fed for 8 weeks with experimental diets which contained different levels of JFE (0%, 0.25%, 0.5%, or 1%). Thereafter, serum non‐specific immune parameters [total immunoglobulin (Ig) as well as alternative complement (ACH50) and lysozyme activity (SL)] and expression of genes involved in intestinal immunity (lyz, tnf‐alpha, il1b, il8, il10, and tgfb) were measured. The results revealed a significant elevation of Ig level in the JFE‐fed fish (p < 0.05) over the control fish. However, there was no significant difference among treated groups in case of serum total Ig. The highest levels of SL and ACH50 were observed in fish fed 1% of JFE. Nonetheless, no significant difference was noticed regarding SL and ACH50 of control and other supplemented groups (0.25% and 0.5% JFE). Also, expression of lyz, tnf‐alpha, and il1b genes increased significantly (p < 0.05) in JFE‐fed fish, in a dose‐dependent manner. On the other hand, significant (p < 0.05) down‐regulation of il110 and tgfb were noticed in treated groups. The present findings suggested that extraction of Jujube, Z. jujube fruit, possesses beneficial effects on immune responses of common carp.  相似文献   
15.
Leather finishing processes using toxic organic solvent based produce volatile organic compounds (VOC), chronic exposure to this chemicals effect on workers' health causing many diseases especially lung cancer. So, polyurethane waterbased was synthesized for application in leather finishing instead of organic solvent based because it’s economic and safety for industry and workers. Preparation of water-based polyurethane (PU) depends on the reaction of polyethylene glycol (PEG, 300) with isophorone diisocyanate (IPDI) and the reaction of IPDI-1,4-butanediol (BDO) together with dimethylolpropionic acid (DMPA), was synthesized by poly-addition polymerization reaction. PU was then modified with different amounts of silicon dioxide nanoparticles (1-5 % SiO2), used as a binder in leather finishing. Leather coated was characterized physically, chemically and thermally by FTIR, GPC, DLS, TEM, SEM and TGA. The results revel that, water vapor permeability (WVP) of leather coated with PU modified with SiO2 showed improvement due to the existence of SiO2 particles which increases the interspaces of the polyurethane coating. SEM showed that when the amount of SiO2 nanoparticles increases, there is uniform nanoparticles accumulated can be observed. EDX prove the presence of Si and O2 elements and the formation of SiO2 nanoparticles. Mechanical properties discussed that tensile strength; tear strength and elongation at break % increase with increase SiO2 concentration until 3 % SiO2 nanoparticles. TGA showed an improvement of thermal stability of coated leather modified with SiO2. Therefore, this study succeeded in preparation of safe, ecofriendly of water-based polyurethane binders which modified with SiO2 for using in leather finishing.  相似文献   
16.
Nannochloropsis salina was grown on a mixture of standard growth media and pre-gasified industrial process water representing effluent from a local biogas plant. The study aimed to investigate the effects of enriched growth media and cultivation time on nutritional composition of Nannochloropsis salina biomass, with a focus on eicosapentaenoic acid (EPA). Variations in fatty acid composition, lipids, protein, amino acids, tocopherols and pigments were studied and results compared to algae cultivated on F/2 media as reference. Mixed growth media and process water enhanced the nutritional quality of Nannochloropsis salina in laboratory scale when compared to algae cultivated in standard F/2 medium. Data from laboratory scale translated to the large scale using a 4000 L flat panel photo-bioreactor system. The algae growth rate in winter conditions in Denmark was slow, but results revealed that large-scale cultivation of Nannochloropsis salina at these conditions could improve the nutritional properties such as EPA, tocopherol, protein and carotenoids compared to laboratory-scale cultivated microalgae. EPA reached 44.2% ± 2.30% of total fatty acids, and α-tocopherol reached 431 ± 28 µg/g of biomass dry weight after 21 days of cultivation. Variations in chemical compositions of Nannochloropsis salina were studied during the course of cultivation. Nannochloropsis salina can be presented as a good candidate for winter time cultivation in Denmark. The resulting biomass is a rich source of EPA and also a good source of protein (amino acids), tocopherols and carotenoids for potential use in aquaculture feed industry.  相似文献   
17.
A 3 × 4 factorial design was used to evaluate the dietary protein requirement and to determine the optimum dietary protein to energy (P/DE) ratio in sub‐yearling Persian sturgeon, Acipenser persicus, reared in the indoor system. Twelve experimental diets (40P16, 40P17, 40P18, 40P19, 45P19, 45P17, 45P18, 45P19, 50P16, 50P17, 50P18 and 50P19) were formulated and prepared to contain three protein levels (40%, 45% and 50%) and four digestible energy levels (16, 17, 18 and 19 kJ g?1 diet) at each protein level. Fish averaging 103.3 ± 3.5 (mean ± SD) were fed one of the experimental diets for 14 weeks. At the end of the experimental period, there were significant energy effects (P < 0.05) on weight gain (WG) and specific growth rate (SGR). Weight gain and SGR tended to decrease, although non‐significantly, with increase in dietary protein levels. Furthermore, there were significant protein and energy interaction effects on WG, SGR, hepatosomatic index and protein efficiency ratio. However, there were no significant dietary protein, energy or their interaction effects on feed efficiency for fish fed all diets. Weight gain and SGR of fish fed 40P19 were significantly higher than those of fish fed 40P16, 45P16, 45P17, 50P16 and 50P17 diets (P < 0.05). There were no significant differences in WG and SGR among fish fed 40P17, 40P18, 40P19, 45P18, 45P19, 50P18 and 50P19 diets. These results may indicate that the optimum dietary protein requirement and the P/DE ratio could be 40% protein and 22.0 mg protein kJ?1 (40P18), respectively, in Persian sturgeon, based on growth performance and feed utilization.  相似文献   
18.
The accuracy of the knowledge of mass transfer parameters(effective moisture diffusivity,mass transfer Biot number and mass transfer coefficient) in the case of frying food,is essential and important for designing,modeling and process optimization.This study is undertaken to develop an approach for determining mass transfer parameters during frying of spherical rice cracker in sunflower oil at 150,170 and 190 ℃.These parameters were evaluated from the plots of dimensionless concentration ratios against time of frying.Effective moisture diffusivity,mass transfer Biot number and mass transfer coefficient ranged between 1.24×10-8 to 2.36×10-8 m2/s,1.96 to 2.34 and 5.51×10-6 to 9.70×10-6 m/s,respectively.Effective moisture diffusivity and mass transfer coefficient were found to increase with an increasing frying temperature,whereas mass transfer Biot number decreased.An Arrhenius-type relationship was found between effective diffusivity coefficient and frying temperature.  相似文献   
19.
This study was conducted to evaluate the feeding value of whole date palm (WDP) with and without enzyme supplementation on aged laying hen’s performance. Apparent metabolizable energy value of WDP was determined by the total collection method using ten adult leghorn cockerels. WDP was substituted with a corn-soybean meal basal diet at 40% level, and then the metabolizable energy of this experimental diet and basal diet was determined. After that, a total number of 256 Bovanz 95-week-old hens were randomly allocated into eight groups consisting of four replicates of eight birds each, based on a 4 × 2 factorial arrangement of the treatments. Eight iso-caloric and iso-nitrogenous experimental diets including one corn-soybean meal-based control diet and two, three, and four corn-soybean meal-based diets included 70, 140, and 210 g/kg ground WDP, respectively. Each of the diets supplemented with two levels of an enzyme (0.0 and 0.07 g/kg Natozim Plus). There was no significant difference in feed intake, feed conversion ratio, egg production, egg mass, eggshell thickness, and Haugh unit among the treatments (P > 0.05). However, yolk color score significantly decreased as dietary WDP level increased. The serum biochemical metabolites were not significantly affected by WDP and enzyme supplementation (P > 0.05). There were no significant differences in the relative weight of different organs except for abdominal fat. Our findings show that using WDP up to 21% of the diet was more economic and had no adverse effect on productive performance and serum metabolites of laying hens. However, WDP had an adverse effect on yolk color which can be ameliorated by carotenoid supplementation.  相似文献   
20.
Abstract

Optimisation of water and nitrogen use is an effective management tool to conserve resources and reduce environmental pollutions. Response surface methodology (RSM) is defined as a collection of mathematical and statistical methods that are used to develop, to improve or to optimize a product or process. In order to determine optimum levels of water, nitrogen and planting density of canola (Brassica napus L.), a 2-year experiment (2010–2011) was carried out by central composite design as RSM at the research station of Ferdowsi University of Mashhad. The treatments were designed based on low and high levels of irrigation (1500 and 4000 m3 ha?1), nitrogen (0 and 400 kg N ha?1) and density (50 and 150 plant m?2) as independent variables. Furthermore, seed yield, nitrogen losses, nitrogen use efficiency (NUE) and water use efficiency (WUE) were measured as response variables in a full quadratic polynomial model. Optimum levels of irrigation, nitrogen and planting density were suggested to achieve the target range of dependent variables based on three scenarios: economic, environmental and eco-environmental. The results showed that increasing irrigation and fertilizer led to an increase in seed yield and nitrogen losses, whereas increasing canola density resulted in an increase in seed yield but a decrease in nitrogen losses. The optimum levels of water, fertilizer and density based on environmental scenario were 1802 m3 ha?1, 11 kg N ha?1 and 122 plant m?2, respectively. To achieve optimum conditions under the economic scenario, it is necessary to use 3411 m3 water ha?1, 178 kg N ha?1 and 119 plant m?2. Amounts of 2347 m3 water ha?1, 92 kg N ha?1 and 114 plant m?2 were found to be the optimum conditions for the eco-environmental scenario. In general, it seems that resource use based on the eco-environmental scenario may be the most favorable cropping strategy for canola production.  相似文献   
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