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141.
Amir Hayat Taj Muhammad Jahangir Muhammad Yar Khuhawar Malik Alamgir Amna Jabbar Siddiqui Syed Ghulam Musharraf 《Journal of Cereal Science》2014
A selective and sensitive HPLC method for the simultaneous determination of gamma amino butyric acid (GABA) and lysine in Pakistani rice varieties was developed. Both analytes were detected in rice varieties as Schiff base derivatives with 2-hydroxynaphthaldehyde. The derivatives were analyzed on a reverse phase C-18 column with Diode Array Detector (DAD) at 254 nm. The calibration curves were found linear over a concentration range of 3.83–34.58 μg/mL for GABA and 5.16–48.68 μg/mL for lysine with a correlation coefficient of 0.998 for both standards. GABA and lysine contents were found higher in brown rice varieties (4.1–6.58 mg/100 g for GABA and 15.1–27.6 mg/100 g for lysine) than the polished varieties (0.32–0.47 mg/100 g GABA and 13.1–19.8 mg/100 g lysine). This method could be used for separation and quantification of GABA and lysine simultaneously in food samples, especially in cereal seeds. 相似文献
142.
Effect of preceding crops and their residues on availability of zinc in a calcareous Zn-deficient soil 总被引:1,自引:0,他引:1
Hadi Habiby Majid Afyuni Amir Hossein Khoshgoftarmanesh Rainer Schulin 《Biology and Fertility of Soils》2014,50(7):1061-1067
Limited information is available on the effect of preceding crop on phytoavailability of zinc (Zn) in soil. This pot experiment examined the effect of four preceding crops including clover, sunflower, safflower, and sorghum residues on shoot and grain Zn uptake by two wheat genotypes differing in Zn-deficiency tolerance Back Cross and Kavir in a calcareous Zn-deficient soil. Incorporation of all preceding crop residues into the soil significantly increased organic matter (OM) content, dissolved organic C (DOC), and diethylene triamine pentaacetic acid (DTPA) extractable Zn concentration in the soil. Residues of safflower and clover had the greatest effect on increasing DOC. Shoot and grain Zn concentrations were increased by incorporating all pre-crop residues into the soil although this increase was greater at safflower and clover treatments. Incorporation of sorghum residues into the soil had a negative effect on shoot and grain dry matter yield of wheat. Incorporation of safflower and clover residues into the soil increased Zn uptake by wheat shoot and grain. There was a positive significant correlation between shoot and grain Zn concentration with DOC in soil solution. It shows that DOC, produced from decomposition of crop residues, has facilitated Zn uptake by roots of wheat plants and particularly its transfer to grains. 相似文献
143.
Shabnam Soltani Amir H. Khoshgoftarmanesh Majid Afyuni Mehran Shrivani Rainer Schulin 《Biology and Fertility of Soils》2014,50(2):239-247
The role of cropping systems practices in agronomic biofortification programs with the aim of increasing micronutrient density in food plants has to be clarified. In these field experiments, the effect of four preceding crops, i.e., sunflower (Heliantus annus L. cv. Allstar), Sudan grass (Sorghum bicolor L. cv. Speed Feed), clover (Trifolium pratense L.), and safflower (Carthamus tinctorius L. cv. Koseh-e-Isfahan), on the total amino acids (AA) and dissolved organic carbon (DOC) concentration in rhizosphere soil solution and grain Zn content of successive wheat (Triticum aestivum cvs. Back Cross and Kavir) was investigated during 2009–2010 and 2010–2011 growing seasons. A fallow treatment was also considered as the control. In both growing seasons, preceding crops increased the concentrations of AA and DOC in the soil solution in comparison with the fallow control treatment; although the magnitude of this increase varied upon the preceding crop type and wheat cultivar. In general, clover and sunflower had greater effect on increasing soil solution DOC probably due to higher decomposability of their litter residues in soil. Preceding crops increased the total AA concentration, on average, by 45.9 % for the first year and 10.8 % for the second year. The preceding sorghum and clover had the highest and lowest influence on the concentration of AA in wheat rhizosphere soil solution, respectively. The preceding crops increased grain wheat Zn concentration and content over the fallow control treatment, although this effect was dependent on the crop type. For “Back Cross”, a positive and significant correlation was found between grain Zn concentration and soil solution DOC concentration (r?=?0.60, P?<?0.05) and particularly AA (r?=?0.76, P?<?0.001), while no such correlation was found for “Kavir”. At the second growing season, the concentration of AA in the rhizosphere of Back Cross was greater than that of Kavir, probably due to higher release of these compounds from the roots. According to the results, the preceding crop significantly affect grain Zn density of the successive wheat, that is, at least in part, by releasing soluble organic ligands into soil solution. 相似文献
144.
Ebrahim Kord Amir Kaffashi Hadi Ghadakchi Fatemeh Eshratabadi Zakaria Bameri Abdelhamed Shoushtari 《Tropical animal health and production》2014,46(3):549-554
Highly pathogenic avian influenza (HPAI) H5N1 virus is causing the death of a large number of wild birds and poultry. HPAI H5N1 was reported in the north of Iran in 2011. In this study, two A/Chicken/Iran/271/2011 and A/Duck/Iran/178/2011 viruses were genetically characterized by sequence analysis of Hemagglutinin (HA) and Neuraminidase (NA) genes. Phylogenetic analysis revealed that these viruses were different from previous Iranian isolates (Clade 2.2) and belonged to the subclade 2.3.2.1. The results showed that the detected viruses are almost identical to each other and closely related to HPAI H5N1 strains isolated in Mongolia in 2010. Based on the amino acid sequence analysis, these viruses at their HA cleavage sites contained the multibasic amino acid motif PQRERRRK-R/GLF lacking a lysine residue compared with the previous reports of the same motif. There is also a 20-amino acid deletion (resides 49–69) in the NA stalk similar to other viruses isolated after 2000. It seems that introduction of HPAI H5N1 to Iran might have happened by wild birds from Mongolian origin virus. 相似文献
145.
Karin Aharonson-Raz Irit Davidson Yael Porat Amira Altory Eyal Klement Amir Steinman 《Journal of Equine Veterinary Science》2014
Equine influenza and equine rhinopneumonitis are among the Office International des Epizooties or the World Organisation for Animal Health notifiable, contagious respiratory diseases. Although vaccination of horses in Israel against equine influenza virus (EIV) and against equine herpesvirus (EHV) is routinely performed, information regarding the occurrence and the epidemiology of the diseases is lacking. We hereby attempt to determine seroprevalence and rate of infection for EHV-1 and 4 and for EIV in horses distributed throughout Israel and describe demographic and environmental risk factors associated with seroprevalence. Despite the fact that last reported isolation of EIV in Israel occurred in 2007, we found a 26.4% (29/110) (95% confidence interval [CI]: 18.18–34.62) seroprevalence for H3N8, a 16.4% (18/110) (95% CI: 9.49–23.31) for H7N7, and a 6.4% (7/110) (95% CI: 1.83–10.97) rate of seroconversion for H3N8, suggesting current and active circulation of EIV in horses in Israel. Age, housing management type, and type of farm activity were significantly associated with seroprevalence, with activities allowing exposure to new horses positively associated with seroprevalence to EIV and an only pasture housing management negatively associated with seroprevalence. No association was detected between other demographic variables (gender, breed, and color) and environmental factors (climatic regions). Seroprevalence to EHV-1 and 4 were very low (<1%) and very high (>99%), respectively, raising questions regarding the appropriate vaccination guidelines. Our findings of the occurrence of EIV in horses in Israel imply an underdiagnosis of this virus in this country and warrant further investigation as to the strains that circulate in this region and their accordance with the current vaccine strains. 相似文献
146.
Amir Hossein Alavi Amir Hossein Gandomi Ali Mollahassani Ali Akbar Heshmati Azadeh Rashed 《植物养料与土壤学杂志》2010,173(3):368-379
This study considers the use of artificial neural networks (ANNs) to predict the maximum dry density (MDD) and optimum moisture content (OMC) of soil‐stabilizer mix. Multilayer perceptron (MLP), one of the most widely used ANN architectures in the literature, is utilized to construct comprehensive and accurate models relating the MDD and OMC of stabilized soil to the properties of natural soil such as particle‐size distribution, plasticity, linear shrinkage, and the type and quantity of stabilizing additives. Five ANN models are constructed using different combinations of the input parameters. Two separate sets of ANN prediction models, one for MDD and the other for OMC, and also a combined ANN model for multiple outputs are developed using the potentially influential input parameters. Relative‐importance values of various inputs of the models are calculated to determine the significance of each of the predictor variables to MDD and OMC. Inferring the most relevant input parameters based on Garson's algorithm, modified ANN models are separately developed for MDD and OMC. The modified ANN models are utilized to introduce explicit formulations of MDD and OMC. A parametric study is also conducted to evaluate the sensitivity of MDD and OMC due to the variation of the most influencing input parameters. A comprehensive set of data including a wide range of soil types obtained from the previously published stabilization test results is used for training and testing the prediction models. The performance of ANN‐based models is subsequently analyzed and compared in detail. The results demonstrate that the accuracy of the proposed models is satisfactory as compared to the experimental results. 相似文献
147.
The onset of protective immunity with MS-H was determined through experimental challenge and compared with the parent strain 86079/7NS. MS-H vaccinates and 86079/7NS inoculates were challenged at 1, 2, 3, 4, 5, and 6 wk after vaccination, then examined 2 wk after challenge for signs of respiratory disease. Serologic results indicated that 100% of MS-H vaccinates had antibodies to MS by 3 wk after vaccination and 100% of 86079/7NS inoculates were positive by 2 wk after inoculation. From 3 wk after vaccination, MS-H vaccinates had a significantly lower incidence of air sac lesions and, from 4 wk after vaccination, a significantly lower air sac lesion severity. In 86079/7NS-inoculated birds, a significantly lower incidence of air sac lesions was observed from 1 wk after inoculation, and air sac lesion severity was significantly lower than the unvaccinated controls at 3 wk after inoculation. It would appear that, under the conditions of this experiment, protective immunity elicited by MS-H appeared at 4 wk after vaccination, slightly later than the appearance of serum antibody. Although the MS-H vaccine was slower to establish protective immunity than 86079/7NS, there was no significant difference between the two strains by 4 wk after vaccination or inoculation. 相似文献
148.
Ghiasian SA Maghsood AH Yazdanpanah H Shephard GS Van Der Westhuizen L Vismer HF Rheeder JP Marasas WF 《Journal of agricultural and food chemistry》2006,54(16):6118-6122
A total of 52 corn samples collected in 2000 from four main corn production provinces of Iran (Fars, Kermanshah, Khuzestan, and Mazandaran) were analyzed for contamination with Fusarium verticillioides and fumonisins (FB(1), FB(2), FB(3), and 3-epi-FB(3)). The mean incidence of F. verticillioides (percent of kernels infected) for these four areas was 26.7, 21.4, 24.9, and 59.0%, respectively. The incidence in Mazandaran was significantly (p < 0.05) above that of the other areas. All samples from Mazandaran were contaminated with fumonisins with a mean level of total fumonisins of 10674 microg/kg. In contrast, the incidence of fumonisin contamination above 10 microg/kg was 53 (8/15), 42 (5/12), and 57% (8/14) in the samples from Fars, Kermanshah, and Khuzestan, respectively, and the corresponding mean total fumonisin levels were 215, 71, and 174 microg/kg, respectively. No statistical differences (p > 0.05) were observed in the fumonisin levels of the corn samples from these three provinces, which were significantly (p < 0.05) lower than the fumonisin contamination in samples from Mazandaran. 相似文献
149.
Jafarlou Ali Mehrban Pirivatlo Saeed Piri Salehi Behrouz Mogbli Amir Hoshang Hoseynzadeh 《Journal of Crop Science and Biotechnology》2021,24(4):449-460
Journal of Crop Science and Biotechnology - This survey is aimed at the assessment of the possible effect of different plant growth regulators (PGRs) on the micropropagation of commercial sweet... 相似文献
150.
Saeidi Z Vatandoost H Akhavan AA Yaghoobi-Ershadi MR Rassi Y Sheikh Z Arandian MH Jafari R Sanei Dehkordi AR 《Pest management science》2012,68(5):669-675
BACKGROUND: Phelebotumus papatsi is considered to be the main vector of zoonotic cutaneous leishmaniasis as well as sand fly fever in Iran. There are several measures for vector control, with emphasis on insecticides. The objective of this study was to determine the baseline susceptibility of this vector to the commonly used insecticides in an endemic focus of the disease in central Iran. P. papatasi collected from the field were used for susceptibility status. Its baseline susceptibility to DDT and pyrethroids was assessed on about 6866 specimens collected from Badrood rural district, Esfahan Province, Iran, during the summer of 2010. The LT50 and LT90 values were measured according to the World Health Organisation (WHO) test using probit analysis and regression lines. RESULTS: Results of tests against female P. papatasi revealed LT50 values to DDT 4%, permethrin 0.75%, deltamethrin 0.1%, cyfluthrin 0.15% and lambdacyhalothrin 0.05% of 1104.97, 182.35, 26.79, 15.42 and 1.48 s respectively. The figures for male P. papatasi were 973.51, 59.5, 4.4, 2.65 and 1.5. CONCLUSION: The results of this study provide a guideline for implementation of different vector control measures. Furthermore, guidelines are needed for monitoring and evaluation of insecticide susceptibility tests against sand flies. Copyright © 2012 Society of Chemical Industry 相似文献