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A survey consisting of 146 first order gullies selected from five sites with different land use, soil and watershed properties was carried out to estimate the parameters of the empirical power function in order to describe the relationship between the gully volume and length in Fars province, Iran. Subsequently, the gullies were clustered into seven groups (“A” to “G”) based on nine morphometric factors. The linearized functions were fitted to the natural logarithms of the volume and length in each group and the parameters “a” and “b” were determined. The obtained “a” and “b” parameters are in the ranges of 1.0–10.8 and 0.8–1.4, respectively. Comparison of “a” and “b” parameters in each group with the mean of nine factors and the mean soil, watershed and land use characteristics in each group showed that the gully volume and average cross section are correlated with the gully depths in different sections and the gully head slopes. Also it was shown that the parameters of fitted functions to the plots of gully volumes versus gully lengths are proportional to width at the gully heads. The gully widths at the top and bottom of the five meter sections are correlated with the average upstream watershed area of the gullies. 相似文献
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Ali Kadivar Habiballah Rashidzadeh Najmeh Davoodian Hasan Nazari Rohallah Dehghani Tafti Heidar Heidari Khoei Hasan Seidi Samani Jahangir Modaresi Ebrahim Ahmadi 《Reproduction in domestic animals》2021,56(2):287-291
Accurate diagnosis of foetal sex in pregnant mare is helpful for many breeders, both for private or commercial purposes. In this study, in order to pre-natal foetal sexing in equine, we used TaqMan duplex real-time PCR to detect the specific regions of SRY and TSPY genes on extracted cell-free foetal DNA from maternal blood. Peripheral blood samples from 50 pregnant Arabian mares with singleton foetuses were collected. Cell-free foetal DNA was extracted from maternal plasma, and duplex real-time PCR assays were performed with TaqMan probes and primers. Amplification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene was used as control of DNA extraction procedure. From the 50 sampled mares, 28 cases had female and 22 mares had male foetuses. The final results for 46 samples were conclusive, and from them, 43 cases were predicted correctly. Sensitivity, specificity and accuracy of the test were 90.48%, 96% and 93.48%, respectively. In conclusion, a TaqMan duplex real-time PCR was set up to pre-natal detection of foetal sex in equine. The method was fast and decreased the false-positive and false-negative results. The technique can be used as a routine procedure in farms by collecting only a blood sample. 相似文献
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To evaluate yield loss models in safflower–redroot pigweed systems, two field experiments were conducted during the 2007 and 2008 growing seasons. The relative yield loss of the crop was recorded in plots laid out in a split-plot design with three irrigation treatments as main plots [100, 75 and 50% FC (field capacity)] and five weed densities (0, 3, 6, 9 and 12 m?2) as subplots in three replicates. Among Cousens, Spitters, and Kropff & Lotz models, Spitters was the best predictor of yield loss and showed the lowest RMSE (0.001–0.002), high Adj-R 2 (0.824–0.929), highest precision (0.962–0.981) and accuracy (constant and systematic biases of 0.000–0.103 and 0.863–1.040, respectively), and random residuals plot. The Cousens, and Kropff & Lotz models showed relatively good fit, although they had higher RMSE values, larger constant and systematic biases, and nonrandom residual plots. The reliability of all models was influenced by irrigation treatment, with generally larger constant and systematic biases at 50% irrigation, causing yield loss under/overprediction under 100 and 50% irrigation, respectively. The parameters of the Spitters model correctly explained the biological function of water shortage on yield response; however, the parameters of other models failed to represent a biologically acceptable yield response function, particularly at 50% irrigation. 相似文献
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Background: Neuroinflammation, as a major outcome of microglia activation, is an important factor for progression of neurodegenerative disorders including Alzheimer''s disease and Parkinson''s disease. Microglial cells, as the first-line defense in the central nervous system, act as a source of neurotoxic factors such as nitric oxide (NO), a free radical which is involved in neuronal cell death. The aim of this study was to inhibit production of NO in activated microglial cells in order to decrease neurological damages that threat the central nervous system. Methods: An in vitro model of a newborn rat brain cell culture was used to examine the effect of betaine on the release of NO induced by lipopolysaccharide (LPS). Briefly, primary microglial cells were stimulated by LPS and after 2 minutes, they were treated by different concentrations of betaine. The production of NO was assessed by the Griess assay while cell viability was determined by the MTT assay. Results: Our investigations indicated that LPS-induced NO release was attenuated by betaine, suggesting that this compound might inhibit NO release. The effects of betaine on NO production in activated microglial cells after 24 h were "dose-dependent". It means that microglial cells which were treated with higher concentrations of betaine, released lower amounts of NO. Also our observations showed that betaine compound has no toxic effect on microglial cells. Conclusion: Betaine has an inhibitory effect on NO release in activated microglial cells and may be an effective therapeutic component to control neurological disorders.Key Words: Betaine, Lipopolysaccharides (LPS), Nitric oxide (NO), Microglia 相似文献
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A novel electrically conductive nanocomposite consisting of poly(N-vinylpyrrolidone) (PVP) modified polyaniline (PANI) and
cloisite clay nanoparticles was obtained via insitu polymerization method. The synthesized nanocomposite was characterized
using FT-IR, XRD, conductivity measurement and cyclic voltammetry techniques. The electrical conductivity measurements of
prepared nanocomposite showed that the nanocomposite is electrically conductive. Also cyclic voltammetry studies revealed
that the synthesized nanocomposite is electro active. Electrochemical corrosion studies including open circuit potential measurements
and tafel tests were carried out in various corrosive environments to evaluate the anticorrosive property of the nanocomposite
coating on iron samples. Results showed that the coating of this nanocomposite on iron was useful in decreasing corrosion
current and corrosion rate of iron in comparison with bare iron and pure polyaniline coated samples. A positive shift in corrosion
potential and a significant decrease in corrosion current were observed for nanocomposite coated iron samples in sodium chloride
3.5 %, hydrochloric acid 0.1 M and sulfuric acid 0.1 M solutions. 相似文献
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In this work homogeneous and adherent nanocomposite of polypyrrole (PPY) with Na+-Cloisite nanoclays was successfully prepared by insitu electropolymerization of pyrrole monomer in the presence of Na+-Cloisite nanoclays. Formation of nanocomposite and incorporation of nanoclays in polypyrrole matrix was endorsed and characterized
by FTIR spectroscopy studies, X-ray diffraction (XRD) pattern and scanning electron microscopy (SEM). The X-ray difraction
patterns showed that PPY was intercalated between clay layers in the order of nanoscale. The morphology of the resulted nanocomposite
was studied by scanning electron micrograph (SEM). Cyclic voltammetry experiments were carried out in different electrolytes
and showed that nanocomposite is electroactive, while conductivity of the nanocomposite derived from four point probe technique
indicated that the resulted nanocomposite is conductive. The anticorrosive properties of a thin layer coating of PPY/Na+-Cloisite nanocomposite on iron coupons was evaluated and compared with pure polypyrrole coating. According to the results
in various corrosive environments PPY/Na+-Cloisite nanocomposite has enhanced corrosion protection effect in comparison to pure polypyrrole coating. It was observed
that the corrosion protection effect was due to the dispersion of nanoclays in polymer matrix, which results in the increase
in the corrosion potential and decrease in corrosion current and corrosion rate. 相似文献
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