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341.
In this study, dissolved air flotation (DAF) was examined as a possible treatment method for the removal of chromium from aqueous solution and plating wastewater. Two coagulants, ferric chloride and poly aluminum chloride (PAC), were used for pretreatment of wastewater. Maximum removal of chromium was achieved for poly aluminum chloride (98 %). Artificial neural network was used for the prediction of the DAF system. The best neuron used for the prediction of chromium removal percentage of interpolated wastewater was 6 %. The mean score error and the coefficient correlation were 0.0007542 and 0.997, respectively. 相似文献
342.
Schönenbrücher H Adhikary R Mukherjee P Casey TA Rasmussen MA Maistrovich FD Hamir AN Kehrli ME Richt JA Petrich JW 《Journal of agricultural and food chemistry》2008,56(15):6220-6226
The removal of central nervous system (CNS) tissues as part of bovine spongiform encephalopathy (BSE) risk material is one of the highest priority tasks to avoid contamination of the human food chain with BSE. No currently available method enables the real-time detection of possible CNS tissue contamination on carcasses during slaughter. The fluorescent pigment lipofuscin is a heterogeneous, high-molecular weight material that has been shown to be enriched in high concentrations in neuronal tissues. In this study, lipofuscin fluorescence was investigated as a marker for real-time detection of CNS contamination. Front-faced fluorescence spectra of brain and spinal cord samples from 11 cattle gave identical, reproducible fluorescence signal patterns with high intensities. The specificity of these spectra was assessed by investigating 13 different non-CNS tissues enabling the differentiation of brain and spinal cord by signal intensity and structure of the spectra, respectively. Small quantities of bovine spinal cord were reliably detected in the presence of raw bovine skeletal muscle, fat, and vertebrae. The presented data are a fundamental basis for the development of a prototype device allowing real-time monitoring of CNS tissue contamination on bovine carcasses and meat cuts. 相似文献
343.
Commercially supplied chicken breast muscle was subjected to simultaneous heat and pressure treatments. Treatment conditions ranged from ambient temperature to 70 degrees C and from 0.1 to 800 MPa, respectively, in various combinations. Texture profile analysis (TPA) of the treated samples was performed to determine changes in muscle hardness. At treatment temperatures up to and including 50 degrees C, heat and pressure acted synergistically to increase muscle hardness. However, at 60 and 70 degrees C, hardness decreased following treatments in excess of 200 MPa. TPA was performed on extracted myofibrillar protein gels that after treatment under similar conditions revealed similar effects of heat and pressure. Differential scanning calorimetry analysis of whole muscle samples revealed that at ambient pressure the unfolding of myosin was completed at 60 degrees C, unlike actin, which completely denatured only above 70 degrees C. With simultaneous pressure treatment at >200 MPa, myosin and actin unfolded at 20 degrees C. Unfolding of myosin and actin could be induced in extracted myofibrillar protein with simultaneous treatment at 200 MPa and 40 degrees C. Electrophoretic analysis indicated high pressure/temperature regimens induced disulfide bonding between myosin chains. 相似文献
344.
Saeid Hazrati Arman Beyraghdar Kashkooli Farhad Habibzadeh Zeinolabedin Tahmasebi-Sarvestani Amir Reza Sadeghi 《Gesunde Pflanzen》2017,69(3):131-137
Application of bio-based edible coatings, which are in line with sustainable agriculture practices, has been a hot topic in recent years. In order to evaluate the effect of Aloe vera L. gel coating, on the store ability of peach fruits, a 30-day postharvest experiment with 10-day sampling intervals was performed. A. vera gel coating had significant positive effects on the weight loss, color change, and sensory evaluation. The amount of weight loss, color change, Total Soluble Solids (TSS) and Titratable Acidity (TA) in coating was lower than control. Furthermore, our results showed that A. vera gel coating can enhance visual properties, and could also lead in more favourable taste and texture. Regarding the obtained results, it can be suggested that A. vera gel coating can enhance the qualitative and quantitative post-harvest traits of fruits, hence, it could be a suitable alternative for chemicals preservative in commercial storage of peach fruits. 相似文献
345.
Independent selection for seed free tryptophan content and vernalization response in chickpea domestication
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Ruth P. van‐Oss Avi Gopher Zohar Kerem Zvi Peleg Simcha Lev‐Yadun Amir Sherman Hong‐Bin Zhang George Vandemark Clare J. Coyne Ofer Reany Shahal Abbo 《Plant Breeding》2018,137(3):290-300
Chickpea shows a distinct domestication trajectory vis‐a‐vis pod dehiscence and growth cycle mediated by vernalization insensitivity compared with its companion Near Eastern legumes. Our objectives were: (i) to map the quantitative trait loci (QTLs) associated with vernalization response and seed free tryptophan in domesticated × wild chickpea progeny and (ii) estimate the genetic correlation between vernalization response and free tryptophan content. A domesticated × wild chickpea cross was used to document phenotypic segregation in both traits and to construct a skeletal genetic map for QTL detection. A number of vernalization response and seed free tryptophan content QTLs were documented in both F2 and F3 generations. No significant genetic correlation between these two traits was observed. Epistatic relationship between two free tryptophan loci was documented. It is evident that selection for high seed tryptophan is easier to accomplish relative to selection for vernalization insensitivity. This suggests that the two traits were selected independently in antiquity, thereby corroborating earlier claims for conscious selection processes associated with chickpea domestication. 相似文献
346.
Muhammad Sohail Saddiq Shahzad M. A. Basra Zulfiqar Ali Amir M. H. Ibrahim 《Archives of Agronomy and Soil Science》2018,64(2):272-284
Identification of novel wheat (Triticum aestivum L.) germplasm is imperative to develop salt tolerant varieties. In the first phase, 400 accessions were screened against high salt stress (200 mM NaCl) on the basis of Na+ accumulation in leaf blade, and 40 genotypes with contrast reaction to salinity were selected. Salt tolerant group (25 genotypes) had higher leaf K+/Na+ ratio, maximum root and shoot lengths, leaf fresh/dry weights and chlorophyll content as compared to the salt sensitive group (15 genotypes). In second phase, physiologically based screening was performed on selected genotypes against varying salinity levels (0, 100 and 200 mM NaCl). GGE biplot analysis indicates that genotypes TURACO, V-03094, V0005, V-04178, Kharchia 65 and V-05121 were the most salt-tolerant and declared winners as depicted by more gaseous exchange relations and growth potential which was strongly correlated with proper Na+, K+ discrimination in leaf and root tissues. Genotypes PBW343*2, NING MAI 50, PGO, PFAU, V-04181, PUNJAB 85, KIRITATI, TAM200/TUI and TAM200 were poor performer due to more Na+ accumulation in leaf ultimately retarded growth. In conclusion, low Na+ accumulation in leaf can be used as the best screening criteria, employing a large set of genotypes in a breeding program. 相似文献
347.
Amir Zarrabi Jafar Yasrebi Abdolmajid Ronaghi Reza Ghasemi Fasaei Abdolmajid Sameni 《Arid Land Research and Management》2018,32(2):170-183
Zinc (Zn) is an essential micronutrient for crop growth. This metal can be found in chemical forms or fractions in the soil. The objective of this study was to investigate the distribution of Zn in special chemical forms using the sequential extraction method after treating eight calcareous soils by zinc sulfate and municipal solid waste (MSW) compost. Zn was separated in seven defined forms as exchangeable (Ex), carbonate (Car), organic (Om), manganese oxide bound (MnOX), amorphous iron oxide bound (FeAOX), crystalline iron oxide bound (FeCOX), and residual (Res). According to the results, the mean concentrations of Zn in chemical forms in untreated soils from higher to lower were 31.84, 8.13, 2.64, 2.57, 0.45, 0.39, and 0.16?mg?kg?1 for the Res, FeCOX, Car, FeAOX, Om, MnOX, and Ex forms, respectively. The total applied Zn to the studied soils from both the sources of zinc sulfate and MSW compost after incubation for 30 days was converted to chemical forms in the following order: Car?>?Res?>?FeCOX?>?Om?>?FeAOX?>?MnOX?>?Ex. On average, 30.3% of total Zn from zinc sulfate and 28.8% of total Zn in the MSW compost were converted into the Car form. The high content of calcium carbonate (CaCO3) in the studied soils is an important factor affecting the conversion of Zn forms, mostly in the Car form through the application of both the inorganic and the organic sources of Zn. 相似文献
348.
Yang YU Wen-sheng HOU Yael Hacham Shi SUN Cun-xiang WU Ifat Matityahu Shi-kui SONG Rachel Amir Tian-fu HAN 《农业科学学报》2018,17(1):54-62
Soybean(Glycine max(L.) Merr.) is a major crop that provides plant-origin protein and oil for humans and livestock.Although the soybean vegetative tissues and seeds provide a major source of high-quality protein,they suffer from low concentration of an essential sulfur-containing amino acid,methionine,which significantly limits their nutritional quality.The level of methionine is mainly controlled by the first unique enzyme of methionine synthesis,cystathione γ-synthase(CGS).Aiming to elevate methionine level in vegetative tissues and seeds,we constitutively over-expressed a feedback-insensitive Arabidopsis CGS(At D-CGS) in soybean cultivars,Zigongdongdou(ZD) and Jilinxiaoli 1(JX).The levels of soluble methionine increased remarkably in leaves of transgenic soybeans compared to wild-type plants(6.6-and 7.3-fold in two transgenic ZD lines,and 3.7-fold in one transgenic JX line).Furthermore,the total methionine contents were significantly increased in seeds of the transgenic ZD lines(1.5-to 4.8-fold increase) and the transgenic JX lines(1.3-to 2.3-fold increase) than in the wild type.The protein contents of the transgenic soybean seeds were significantly elevated compared to the wild type,suggesting that the scarcity of methionine in soybeans may limit protein accumulation in soybean seeds.The increased protein content did not alter the profile of major storage proteins in the seeds.Generally,this study provides a promising strategy to increase the levels of methionine and protein in soybean through the breeding programs. 相似文献
349.
Shahram Torabian Morteza Zahedi Amir Hossein Khoshgoftar 《Journal of plant nutrition》2017,40(5):615-623
This study investigated the effects of foliar spray of normal and nano-particles of iron sulfate (FeSO4) on the response of sunflower cultivars to salinity. Treatments included five cultivars (Alstar, Olsion, Yourflor, Hysun36 and Hysun33), two salinity levels (0 and 100 mM sodium chloride (NaCl)), and three levels of fertilizer application. Fertilizer treatments were the foliar application of normal and nano-particles of FeSO4. Foliar application of FeSO4 in either form increased leaf area, shoot dry weight, net carbon dioxide (CO2) assimilation rate (A), sub-stomatal CO2 concentration (Ci), chlorophyll content, Fv/Fm and iron (Fe) content and decreased sodium (Na) content in leaves. The extent of increase in chlorophyll a content by foliar spray of FeSO4 nano-particles was significantly greater than normal form. The results showed that the FeSO4 nano-particles increased biomass production of sunflower plants greater in comparison with normal form, although no significant difference was found between two forms. 相似文献
350.
Amir Hossein Toorani Leila Doostdar Kalkenari 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(8):723-729
The citrus cottony scale, Pulvinaria aurantii Cockerell, is the most important pest of citrus orchards in northern Iran in recent years. Owing to the harmful impacts of chemical insecticides, the use of biorational pesticides seems a safe and convenient way to control this pest. The present investigation was set up to study contact toxicity of various biorational and chemical compounds on the first, second instar nymph and overwintering adult of the citrus cottony scale, P. aurantii, and its predator, Cryptolaemus montrouzieri Mulsant under field conditions. The results indicated that the highest percentage of mortality of first instar nymph of the citrus cottony scale was observed in the Dayabon treatment of 9 and 10?ml/L, 100.0%?±?0.0% and the lowest percentage was observed in Palizin treatment of 1.5?ml/L, 34.7%?±?2.9%. In the second instar nymph, the highest mortality was seen in the Dursban treatment of 2?ml/L, 94.7%?±?2.4% and the lowest mortality in the Palizin treatment of 1.5?ml/L, 30.0%?±?2.3%. Also, for overwintering adults Dayabon 10?ml/L caused the highest mortality, 96.0%?±?4.0% during 24?h. In the case of ladybird insects, the highest and lowest percentage of mortality was observed in the Dursban treatment of 2?ml/L, 76.7%?±?8.8%, Dayabon 5?ml/L, and Palizin 2?ml/L, 3.3%?±?3.3%, respectively. The highest and lowest mortality rate of larvae of ladybird was estimated in the Dursban treatment of 2?ml/L, 83.3%?±?3.3% and Dayabon 5?ml/L, 3.3%?±?3.3%, respectively. Also, for overwintering predator adults Palizin 1.5?ml/L had the lowest mortality, 3.3%?±?3.3% during 24?h and this rate remain unchanged after 96?h after treatment. According to the results obtained, treatments with Dayabon 9 and 10?ml/L, can be a viable alternative to other high-risk chemical pesticides in addition to effectively controlling citrus cottony scale without having any adverse impacts on predator ladybird. 相似文献