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41.
Mohammad Reza Neyshaburi Hossein Bayat Kourosh Mohammadi Nader Nariman-Zadeh Mahdi Irannejad 《Archives of Agronomy and Soil Science》2013,59(2):257-273
Soil water retention characteristic is required for modeling of water and substance movement in unsaturated soils and need to be estimated using indirect methods. Point pedotransfer functions (PTFs) for prediction of soil water content at matric suctions of 1, 5, 25, 50, and 1500 kPa were developed and validated using a data-set of 148 soil samples from Hamedan and Guilan provinces, Iran, by multiobjective group method of data handling (mGMDH). In addition to textural and structural properties, fractal parameters of the power-law fractal models for both particles and aggregates distributions were also included as predictors. Their inclusion significantly improved the PTFs’ accuracy and reliability. The aggregate size distribution fractal parameters ranked next to the particle size distribution (PSD) in terms of prediction accuracy. The mGMDH-derived PTFs were significantly more reliable than those by artificial neural networks but their accuracies were practically the same. Similarity between the fractal behavior of particle and void size distributions may contribute to the improvement of the derived PTFs using PSD fractal parameters. It means that both distributions of the pore and particle size represent the fractal behavior and can be described by fractal models. 相似文献
42.
Hossein Ali Ghasemi Mehdi Kazemi-Bonchenari Amir Hossein Khaltabadi-Farahani Mahdi Khodaei Motlagh 《Tropical animal health and production》2013,45(7):1635-1640
A two-month trial was conducted to investigate the effects of pelleting rations with 70:30, 65:35, and 60:40 concentrate to high-quality roughage (alfalfa hay) ratios on hematological and biochemical parameters of ostriches. A total of 18 seven-month-old male ostrich chicks, initially weighing an average of 60–70 kg, were distributed into three different outdoor paddocks at a stocking density of six birds per paddock. In the morning, blood collection was made from the wing vein after about 12 h of fasting. All rations resulted in no significant change in hematological parameters. However, with increasing alfalfa inclusion rate, the heterophil/lymphocyte ratio tended to be lower (P?=?0.089); whereas the values of hemoglobin, packed cell volume (PCV), and mean corpuscular hemoglobin (MCH) tended to be higher (P values 0.069, 0.072 and 0.094, respectively). In terms of plasma biochemical parameters, increasing the ratio of concentrate to alfalfa hay in ostrich diets resulted in significant (P?<?0.05) depression in the values of glucose (up to 20.2 %), total cholesterol (up to 19.2 %), creatine kinase (up to 27.9 %), and aspartate aminotransferase (up to 29.9 %). Additionally, the 65:35 or 60:40 rations caused a decrease in low-density lipoprotein cholesterol level (27.9 and 42 %, respectively; P?=?0.008) compared to the 70:40 ration. Without exception, no rations affected the values of leukocyte subsets, total protein, albumin, globulin, uric acid, alanine aminotransferase, gamma glutamyl transferase, triglycerides, high-density lipoprotein cholesterol, and very low density lipoprotein. Based on our results, the concentrate to alfalfa ratio of 60:40 could be suggested as optimum ratio for good health conditions of juvenile ostriches. 相似文献
43.
Elham Sadat Yazdi Almodarresi Javad Mokhtari Seyed Mohammad Taghi Almodarresi Mahdi Nouri Ali Shams Nateri 《Fibers and Polymers》2013,14(7):1196-1202
Conventional theory for color matching is Kubelka-Munk, but it fails in some situations. New intelligent procedures such as neural networks could learn the behavior of a complex system and produce accurate prediction. This paper investigates the ability of MLP (multiple layer perceptron) neural network for color matching of cotton fabric. Three reactive dyes, namely Levafix Red CA, Levafix Yellow CA and Levafix Blue CA were used for experiments. The dyed samples were scanned and L * a * b * histogram were extracted. Different neural networks were trained and tested using L * a * b * histogram of fabric’s images and also L * a * b * values (D65, 10°) of fabrics. The results were encouraging. For neural networks including the L * a * b * histogram in input vector, colorants and their concentration were predicted with a mean square error (MSE) less than 10?5 and an average value of color difference (CMC (1:2)) less than 1.5 for approximately 80 % of testing data. 相似文献
44.
In this study, the role of the globin moiety in the structure of this pigment has been evaluated, using myoglobin and hemin as model systems. After the synthesis of the cured pigment from the compounds used in this study, the absorption spectra, Fourier transform infrared spectroscopy (FTIR), and electrospray ionization (ESI)/MS spectroscopy were used to evaluate the chemical structure. Results indicated that the UV/visible, IR absorption, and mass spectroscopy of the cured pigment produced from myoglobin and its counterpart without the globin moiety, hemin, are different. Whereas myoglobin produced mononitrosylheme, hemin converted to dinitrosylheme, but probably the second nitric oxide group attached to the propionate side chain of the heme ring. It seems that the globin moiety protected heme ring against the second nitric oxide group. 相似文献
45.
Marjan Zargar Seyed Hadi Razavi Seyed Mahdi Ojagh 《Journal Of Aquatic Food Product Technology》2013,22(8):1311-1322
ABSTRACTIn the present study, aqueous solutions of sodium caseinate (SC) 8% (w/w) were provided in the form of four treatments—including SC without any essential oil (EO) as well as SC with 0.25, 0.5, and 1% (v/w) concentrations of Zataria moltiflora EO. Fish samples were treated with aqueous solutions and stored at 4 ± 1°C for 20 days. The control and treated fish samples were analyzed for chemical (total volatile basic nitrogen, pH, thiobarbituric acid, peroxide value), microbiological (total viable count and psychrotrophic count), and sensory analyses every 4 days. Based on results, SC edible coating had no antimicrobial effect but acted like a barrier against the fish flesh contamination. Moreover, incorporating Zataria moltiflora EO with SC edible coating reduces peroxide value and thiobarbituric acid-reactive substances values as well as the chemical and microbiological spoilage of refrigerated ?sh samples. Furthermore, sensory evaluation results showed that the presence of thyme oil improved the sensory quality of the rainbow trout. 相似文献
46.
Electrically conductive substrates with chromic behavior are prepared using conductive polymer coating of the substrate. Poly
(3-methylthiophene) (P3MT) — coated polyester fabric with specific electrical and chromic properties, for instance electrochromic
and piezochromic behavior, was successfully obtained by chemical polymerization with the help of continuous and speed stirring
technique. The effect of polymerization time, temperature and oxidant concentration on conductivity of the P3MT-coated fabric
was studied. The presence of P3MT particles on the surface of the coated substrate was confirmed by scanning electron microscopy
(SEM), fourier transform infrared (FTIR) and UV-Vis spectroscopy, electrical surface resistivity, pressure and applied voltage
dependence visible reflectance spectrophotometer measurements, and X-ray diffraction (XRD) analysis. The blue shift of c95
nm in wavelength of maximum absorption observed in the reflectance spectra of coated polyester fabric. Under high pressure,
the P3MT-coated polyester fabric demonstrated piezochromism. The coated substrate also showed electrochromic behavior under
an electrical applied voltage of 12 V. 相似文献
47.
Safoora Dehghanipoodeh Cyrus Ghobadi Baharam Baninasab Mahdi Gheysari Siamak Shirani Bidabadi 《Journal of plant nutrition》2016,39(4):502-507
Silicon (Si) is considered as a beneficial element to higher plants especially under stress conditions. A factorial experiment, in a completely randomized design with four replications, was used to investigate the effects of two application methods (spraying and soil drenching) and eight levels of Si compounds including 0, 5, 10 and 15 mM of potassium silicate (K2SiO3) and 0, 5, 10 and 15 mM of nanosilica (SiO2). The results indicated that Si application (all or some treatments) decreased transpiration, specific leaf area, petiole length, and promoted the flowering, fruit firmness, leaf/crown number, fresh and dry weight of shoot and root, water use efficiency. They also showed it did not affect the fruit set percentage, yield, chlorophyll index, total soluble solid, leaf area, fresh and dry weight of crown, photosynthesis, stomatal conductance, internal carbon dioxide (CO2) concentration and mesophyll efficiency of strawberry. The results suggest the beneficial effects of Si on growth and development of strawberry. 相似文献
48.
49.
Reza Mohsenian Kouchaksaraee Fengjie Li Melika Nazemi Mahdi Moridi Farimani Deniz Tasdemir 《Marine drugs》2021,19(8)
The Persian Gulf is a unique and biologically diverse marine environment dominated by invertebrates. In continuation of our research interest in the chemistry and biological activity of marine sponges from the Persian Gulf, we selected the excavating sponge Cliona celata for detailed metabolome analyses, in vitro bioactivity screening, and chemical isolation studies. A UPLC-MS/MS (MS2) molecular-networking-based dereplication strategy allowed annotation and structural prediction of various diketopiperazines (DKPs) and etzionin-type diketopiperazine hydroxamates (DKPHs) in the crude sponge extract. The molecular-networking-guided isolation approach applied to the crude extract afforded the DKPH etzionin (1) and its two new derivatives, clioetzionin A (2) and clioetzionin B (3). Another new modified DKP (4) was identified by MS/MS analyses but could not be isolated in sufficient quantities to confirm its structure. The chemical characterization of the purified DKPHs 1–3 was performed by a combination of 1D and 2D NMR spectroscopy, HRMS, HRMS/MS, and [α]D analyses. Compounds 1 and 2 exhibited broad antibacterial, antifungal, and anticancer activities, with IC50 values ranging from 19.6 to 159.1 µM. This is the first study investigating the chemical constituents of a C. celata specimen from the Persian Gulf. It is also the first report of full spectroscopic data of etzionin based on extensive spectroscopic analyses. 相似文献
50.
Sayedeh Saba Bilgrami Saadollah Houshmand Mahdi Kadivar Baratali Fakheri Vahid Shariati 《Archives of Agronomy and Soil Science》2018,64(3):331-346
Micronutrient deficiency is one of the most common and widespread nutritional issues. Among the factors mitigating the bioavailability of Zn (zinc) and Fe (iron), phytic acid plays a key role; therefore, in order to scrutinize genetic alterations ?related to micronutrient and phytate contents, we examined the concentrations of zinc, iron, and phytic acid, as well as its mole ratio to ?zinc in various wheat species grown in two planting seasons. The concentrations of phytic acid and its mole ratio to zinc were 0.61?1.55 g kg?1 dry weight and 1.88?4.17 for autumn, and 0.97?2.02 g kg?1 dry weight and 2.10?4.05 for spring planting. There was a significant discrepancy among wheat species; tritipyrum had the highest concentration of iron, phytic acid and its mole ratio to zinc, and T. monococcum and T. aestivum recorded reasonable zinc bioavailability. Correlation studies between grain phytic acid concentrations and other measured traits revealed various relationships, denoting an irrefutable impact of planting season and wheat ploidy levels on modification of wheat genotypes. The characters contributing more positively with principal component (PC) 1 were Zn and Fe under spring planting and Fe under autumn planting. Spike number per square meter, biological yield and grain yield in spring cultivation, and grain zinc concentration in autumn cultivation were positively correlated to principal component (PC) 2. Given that the concentration of Fe and Zn in all the studied genotypes is relatively high and due to the existence of other desirable agronomic traits, this study believes that it could possibly enhance the applicability of some of these genotypes for breeding purposes. 相似文献