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71.
Isa Esfandiarpour-Borujeni Seyed Javad Hosseinifard Hossein Shirani Maryam Zeinadini Ali Asghar Besalatpour 《Communications in Soil Science and Plant Analysis》2018,49(12):1474-1490
The main objective of this study was to evaluate the potential use of a hybrid Genetic Algorithm-Artificial Neural Network (GA–ANN) method for predicting pistachio yield and for identifying the determinant factors affecting pistachio yield in Rafsanjan region, Iran. A total of 142 pistachio orchards were selected randomly and soil samples were taken at three depths. Besides, water samples and leaves from branches without fruit were taken in each sampling point. Management information and pistachio yields were achieved by completing a questionnaire. Primarily, 58 variables affecting pistachio yield were measured, and then 26 out of them were selected by minimizing mean square error (MSE) using a feature selection (FS) method. The results showed that the accuracy of the method was acceptable. Furthermore, the sensitivity analysis showed that the main determinant features affecting the pistachio yield were the irrigation water amount, leaf phosphorus, soil soluble magnesium, electrical conductivity (EC), and leaf nitrogen. 相似文献
72.
Noreen Khalid Ali Noman Muhammad Aqeel Naila Hadayat Sumreen Anjum 《Journal of plant nutrition》2018,41(5):584-595
A study was conducted to determine the effect of macronutrients (NPK) in alleviating the adverse effects of simulated acid rain (SAR) on sunflower (Helianthus annuus L.). In addition to control (T0), three different treatments, i.e., SAR (HNO3) of pH 3 (T1), NPK (T2), and SAR + NPK (T3), were applied on two sunflower cultivars, i.e., FH-37 and FH-385. The experiment was set up in CRD (completely randomized design) with four replicates of each treatment. Chlorophyll a, b, total chlorophyll, carotenoids, ion contents (NPK), and gas exchange characters were determined. Acid rain remarkably reduced the chlorophyll pigments, NPK ionic content, photosynthetic rate, transpiration rate, and stomatal conductance, while an increase in internal CO2 concentration and water use efficiency was noted in both the cultivars. The mixture of NPK with SAR exhibited positive impact to lessen the toxicity caused by acid. Among cultivars, FH-385 showed better performance as compared to FH-37. 相似文献
73.
74.
Bose M Hao X Ju J Husain A Park S Lambert JD Yang CS 《Journal of agricultural and food chemistry》2007,55(19):7695-7700
The effect of a combination of (-)-epigallocatechin-3-gallate (EGCG) with fish oil on intestinal tumorigenesis in Apc (Min/+) mice fed a high-fat diet was investigated in the present study. The combined treatment of EGCG and fish oil for 9 weeks reduced the tumor number by 53% as compared to controls while neither agent alone had a significant effect. Apoptosis was significantly increased in all treatment groups. beta-Catenin nuclear positivity in adenomas from the combination group was lower than control mice, implicating the modulation of Wnt signaling by the combination. Fish oil and the combination significantly reduced prostaglandin E 2 (PGE 2) levels in small intestinal tumors as compared to controls, suggesting modulation of aberrant arachidonic acid metabolism by fish oil. Akt phosphorylation in adenomas was significantly reduced in all treatment groups, which may have contributed to the observed increase in apoptosis. The results indicate that a combination of low doses of EGCG and fish oil can inhibit tumor multiplicity in Apc (Min/+) mice. 相似文献
75.
Ghassempour A Nojavan S Talebpour Z Amiri AA Najafi NM 《Journal of agricultural and food chemistry》2004,52(21):6384-6388
In this approach, a derivatization method is described for monitoring of organic acids in fermentation media without any separation step. The aqueous phase of fermentation media was evaporated and heated in a silylation reagent to form trimethylsilyl (TMS) derivatives. The silylated compounds are analyzed by 29Si nuclear magnetic resonance (29Si NMR) and gas chromatography-mass spectrometry (GC-MS). 29Si NMR can qualitatively monitor the components produced in the Krebs cycle. Quantification of these compounds is investigated by using selected ion monitoring mode of mass spectrometry. In this mode, mass to charge (m/z) values of their [M - 15]+ ions, which are 465, 275, 247, 221, 335, 251, and 313 of TMS derivatives of citric, alpha-ketoglutaric, succinic, fumaric, l-malic, oxaloacetic, and palmitic (as an internal standard), acids, respectively, are used. The limit of detection and the linear working range for derivatized citric acid were found to be 0.1 mg L(-1) and 10-3 x 10(4) mg L(-1). The relative standard deviation of the method for five replicates was 2.1%. The average recovery efficiency for citric acid added to culture media was approximately 97.2%. Quantitative results of GC-MS are compared with those obtained by an ultraviolet-visible method. 相似文献
76.
Genetic polymorphism of plastid DNA in Tunisian date-palm germplasm (Phoenix dactylifera L.) detected with PCR-RFLP 总被引:1,自引:0,他引:1
Sakka Hela Zehdi Salwa Ould Mohamed Salem Ali Rhouma Abdelmajid Marrakchi Mohamed Trifi Mokhtar 《Genetic Resources and Crop Evolution》2004,51(5):479-487
Fifteen plastid fragments were amplified from a set of Tunisian date-palm accessions by PCR with consensus primers and analysed by RFLP. Polymorphic DNA bands were obtained as reliable molecular markers to estimate genetic distances among the accessions and to examine their phylogenetic relationships. The ctDNA PCR-RFLP method permitted the identification of two haplotypes that differ in the presence or absence of the HinfI restriction site. Phenetic groups composed of cultivars clustered together but does not constitute monophyletic groups. This typology agrees with the haplotypes' organization and provides a common genetic background within the implied varieties. 相似文献
77.
Mohammad Faraji Masoud Jafarizadeh Ali Mohammadian Behbahani 《Archives of Agronomy and Soil Science》2017,63(11):1523-1534
Although root crops are widely cultivated in Iran, little is known about soil loss due to crop harvesting (SLCH). We assessed the annual exported soil, soil organic matter (SOM) and nutrients from 47 farms under root crops in southwestern Iran. Soil losses for garlic, potato, sugar beet, radish and beetroot were estimated as 6.27, 2.52, 2.26, 4.10 and 6.95, Mg ha?1, respectively, which on average was of the order of soil losses by water erosion in the watershed basins of Iran. Total N, P2O5 and K2O losses were estimated as 36.61, 1.10 and 31.50 kg ha?1 and their costs as 18.24, 0.74 and 19.93 USAlthough root crops are widely cultivated in Iran, little is known about soil loss due to crop harvesting (SLCH). We assessed the annual exported soil, soil organic matter (SOM) and nutrients from 47 farms under root crops in southwestern Iran. Soil losses for garlic, potato, sugar beet, radish and beetroot were estimated as 6.27, 2.52, 2.26, 4.10 and 6.95, Mg ha?1, respectively, which on average was of the order of soil losses by water erosion in the watershed basins of Iran. Total N, P2O5 and K2O losses were estimated as 36.61, 1.10 and 31.50 kg ha?1 and their costs as 18.24, 0.74 and 19.93 US$ ha?1, respectively. For the whole country, total soil, N, P2O5, K2O and SOM losses for garlic, potato and sugar beet were estimated as 731.7 × 103, 836, 27, 476 and 14.5 × 103 Mg, respectively (radish and beetroot were excluded due to no reliable data on their planted areas). Correlation analysis showed no significant relationship between soil properties and SLCH (except soil moisture content for radish and clay content for beetroot). The findings indicated that the exported soil, SOM and nutrients were at such levels that SLCH should be considered in soil erosion studies. 相似文献
78.
Micromechanics of wood subjected to axial tension 总被引:5,自引:0,他引:5
Parviz Navi Pramod K. Rastogi Valérie Gresse Ali Tolou 《Wood Science and Technology》1995,29(6):411-429
Summary The behaviour of a small group of wood fibers of Sitka spruce during tensile loading is investigated. The load-extension curves for both early and late wood fibers consist of three distinct segments. The first segment is almost a straight line, at some stage of loading a yield point is observed. Beyond this point the specimen becomes less stiff and undergoes a large, mainly irreversible deformation. As the load is increased further, the curve exhibits the third segment showed by a significant change in slope. These curves look different from those obtained on thick specimens. In this respect, the behaviour of a thin wood specimen subjected to cyclic type tensile loading along its longitudinal direction is also illustrated. Based on wood microstructure, a model is presented to interpret the evolution of the Young's modulus of a wood fiber during tensile loading. The model considers wood as an assembly of cylindrical fibers pasted together in a longitudinal direction. We have assumed the cell wall to comprise only an S2 layer made of a composite material consisting of a lignin and hemicellulose matrix reinforced by helical microfibrils along the fiber. Furthermore, it is assumed that the microfibril angle a in the S2 layer is not uniform along the fiber axis and matrix degradation occurs in the zones where the microfibril angles are bigger. The validity of this assumption is verified by using holographic interferometry to visualize the displacement field of the specimen's surface under tension.The work reported in this paper is supported by a grant from the Swiss National Science Foundation, and its support is gratefully acknowledged 相似文献
79.
盐胁迫对扁桃砧木叶片SOD、POD和CAT活性的影响 总被引:4,自引:0,他引:4
以温室盆栽的3种扁桃砧木为材料,研究了不同浓度的NaCl、Na2SO4和不同胁迫时间对其叶片活性氧代谢变化的影响.结果表明:NaCl和Na2SO4胁迫下,石头扁桃,桃扁桃和毛桃叶片中POD、CAT活性均随盐浓度的增加而升高,而随着盐胁迫时间的延长其活性有所下降,但都高于对照.SOD活性均随盐浓度的增加先升高后下降,而且后期下降幅度很大.与NaCl胁迫相比,Na2SO4胁迫下这3种砧木叶片中POD、CAT和SOD活性低.从2种盐胁迫下POD、CAT和SOD活性变化规律初步判断这3种砧木的抗盐能力强弱为桃扁桃>毛桃>石头扁桃. 相似文献
80.
Radar soundings of the subsurface of Mars 总被引:2,自引:0,他引:2
Picardi G Plaut JJ Biccari D Bombaci O Calabrese D Cartacci M Cicchetti A Clifford SM Edenhofer P Farrell WM Federico C Frigeri A Gurnett DA Hagfors T Heggy E Herique A Huff RL Ivanov AB Johnson WT Jordan RL Kirchner DL Kofman W Leuschen CJ Nielsen E Orosei R Pettinelli E Phillips RJ Plettemeier D Safaeinili A Seu R Stofan ER Vannaroni G Watters TR Zampolini E 《Science (New York, N.Y.)》2005,310(5756):1925-1928
The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick. 相似文献