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For estimating infiltration properties of surface irrigation, some ‘quick’ and easy methods have been developed. The main objective of this study was to evaluate different ‘quick’ methods and to compare the obtained results with two new methods proposed based on the Shepard one-point approach. For this purpose, data sets measured in six borders and five furrows were used for evaluating different methods. Using the volume balance equation and estimated infiltration parameters, the total infiltrated volume and advance times were predicted to evaluate the accuracy of estimated infiltration parameters. The results showed that the modified Mailapalli and Elliott and Walker methods provided the lowest errors for both furrow and border irrigations. The Elliott and Walker method predicted advance times with highest accuracy. There was very small difference between the Shepard and new proposed one-point methods. The performance of the Elliott and Walker method was slightly better than the new proposed two-point method for the experimental furrows, while a minor difference was found for the experimental borders. The results also showed that the performance of the Elliot and Walker method would be improved using binomial approximation instead of Kiefer approximation.  相似文献   
63.
Castanea sativa is a valuable tree species in Hyrcanian forests, an evolutionary relict ecosystem whose communities suffer from overexploitation and fungal diseases. In the current study, three species delimitation methods were utilized with ITS regions sequencing to determine the taxonomic status of Septoria causing leaf blotch of C. sativa in Hyrcanian forests. The results indicated that the length of ITS region in the genus Septoria (extracted from GenBank) varied from 650 to 680 bp. There were almost three times more variable sites in ITS1 than in ITS2. The ITS2 secondary structure of Hyrcanian Septoria community had the highest similarity with Septoria castaneicola, except for some differences in helix II and III. Also, Hyrcanian samples had minimum genetic distances with S. castaneicola and maximum with Septoria quercicola. The maximum parsimony method divided the studied Septoria genus into three distinct clades, mostly located in clade I. Clade II consisted entirely of Septoria aciculosa, while clade III contained S. castaneicola as well as Hyrcanian samples.  相似文献   
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Inoculation of wheat and corn grains with formulations of Azospirillum brasilense significantly increased seedling growth parameters of wheat and corn compared to untreated controls. Inoculation with Azospirillum and supplemental Trichoderma harzianum free or coimmobilized in calcium alginate resulted in significant increase in all plant growth parameters in addition to improving plant nutrient-content [phosphorus (P), potassium (K), and calcium (Ca)]. Grain treatments with T. harzianum alone or in a combination with A. brasilense were protected from invasion by Fusarium in a pot experiment. Nitrogen (N) fixation was investigated by A. brasilense free or double inoculated with T. harzianum in soil amended with different C-sources; also, phosphate solubilization was tested by these two organisms. Single and double inoculation with A. brasilense and/or T. harzianum improved wheat yield growth parameters in addition to seed protein; therefore, immobilized and coimmobilized formulations could be used as biofertilizer and biopesticide, and might be recommended to avoid the extensive use of the agrochemicals.  相似文献   
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Polymer matrix composites (PMCs) owing to their outstanding properties such as high strength, low weight, high thermal stability and chemical resistance are broadly utilized in various industries. In the present work, the influence of silanized CaCO3 (S-CaCO3) with 3-aminopropyltrimethoxysilane (3-APTMS) coupling agent at different values (0, 1, 3 and 5 wt.% with respect to the matrix) on the mechanical behavior of basalt fibers (BF)/epoxy composites was examined. BF-reinforced composites were fabricated via hand lay-up technique. Experimental results from three-point bending and tensile tests showed that with the dispersion of 3 wt.% S-CaCO3, flexural strength, flexural modulus, tensile strength and tensile modulus enhanced by 28 %, 35 %, 20 % and 30 %, respectively. Microscopic examinations revealed that the development of the mechanical properties of fibrous composites with the incorporation of modified CaCO3 was related to enhancement in the load transfer between the nanocomposite matrix and BF as well as enhanced mechanical properties of the matrix part.  相似文献   
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Aquaculture International - The objective of the present work was to survey the effects of different sources of zinc supplements on serum enzymatic activities, the expression of genes related to...  相似文献   
69.

Euclinostomum heterostomum and Euclinostomum ardeolae, both encysted metacercariae (EMC), were found to infect farmed Oreochromis niloticus in the Sahary fish hatchery and wild O. niloticus, Sarotherodon galilaeus, and Tilapia zillii in Lake Nasser, Aswan Governorate, Egypt, at a prevalence of 25.25% and an infection intensity of 1–14 EMC/fish. Macroscopic and microscopic examinations were used to identify them morphologically. PCR amplification, sequencing of the 28S large ribosomal RNA region, and phylogenetic analysis were used for molecular characterization. E. heterostomum and E. ardeolae were isolated from farmed O. niloticus kidneys, peritoneum, abdominal cavity, and under the gills attached to the head bone at prevalence of 13.5% and 6%, respectively, and from wild O. niloticus, S. galilaeus, and T. zillii at a prevalence of 15% and 4.5%, 18% and 10%, and 22.5% and 11.5% respectively. The molecular analyses of rRNA-28S marker revealed that the two Euclinostomum species examined are related yet distinct. This is the first molecular and phylogenetic evidence linking E. ardeolae to Euclinostomum. The present study added two new sequences to the GenBank databases for the genus Eulinostomum from Egypt, with accession numbers MW604803 and MW604806. Euclinostomum spp. have been shown to have detrimental and destructive effects on the kidneys of infected fish; these effects may eventually result in the parasites’ cysts replacing the kidney’s tissues. The kidneys of tilapia spp. infected with Euclinostomum spp. displayed degenerative alterations, with dilated renal tubules associated with migratory tunnels composed primarily of leucocytic infiltrations. Euclinostomum spp. exhibited clear hemophagic characteristics.

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In this study, a temperature sensitive shape memory polymer (SMP) system based on polylactic acid (PLA) has been developed and the effect of graphene nanoplatelets (GNPs) on the shape memory properties was evaluated. Dispersion of GNPs in PLA was improved with the aid of a zwitterionic surfactant. X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed that the surface modified graphene nanoplatelets (SMGNPs) were exfoliated and homogenously dispersed in the PLA matrix due to enhancement of the polymer-graphene interaction. Mechanical properties of the samples namely stiffness and elasticity were increased upon incorporation of graphene nanoplatelets accompanied by their good dispersion in the PLA matrix. Furthermore, differential scanning calorimetry (DSC) revealed that the nucleation effect of graphene promote the crystallization and noticeably enhanced the degree of crystallinity. Finally, prominent mechanical properties along with high degree of crystallization due to fine dispersion of surface modified graphenes, resulted in drastic improvement in shape memory performance.  相似文献   
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