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1.
In this study, the prediction of pine mistletoe distribution in Scots pine ecosystems was explored using remote sensing variables to compare the multilayer perceptron (MLP) artificial neural network (ANN) and logistic regression (LR) model performances. For this purpose, 109 sample plots were distinguished in pure Scots pine forests (natural) in the Eastern Black Sea Region of Turkey. Distinguishing mistletoe-infected stands (69) and uninfected stands (40) was performed with field observations. The variables acquired from Landsat 8 (Level 1) images were used as independent variables for independent-sample t-test, MLP ANN and LR models. Remote sensing variables indicated that mistletoe-infected stands were in drier areas with a lower vegetation-leaf area index. Based on the performance results of both models, the sensitivity (SEN), specificity (SPE), positive predictive value (PPV), negative predictive value (NPV) and accuracy of the MLP ANN model were superior to those of the LR model. The prediction percentages (SEN, SPE, PPV and NPV) of mistletoe-infected stands were better than the prediction percentages of uninfected stands. The prediction accuracies of LR and MLP ANN models were 74.3% and 89.6%, respectively. However, all remote sensing variables were included in the prediction equation of the MLP ANN model, while the thermal infrared 1 (TIRS1) variable was included in the LR model. In the MLP ANN model, the TIRS1 variable also had the highest normalized importance (100%). The area under the curve (AUC) value for identifying the mistletoe-infected stands of Scots pine forests used by the MLP ANN model (0.892 ± 0.034) was higher than in the LR model (0.838 ± 0.039), explaining the more accurate predictions obtained from the MLP ANN model. The MLP ANN model showed much better performance than the LR model. The results of this study are expected to make important contributions to the identification of potential mistletoe-infected areas. 相似文献
2.
Increasing irrigation costs and declining water availability compel producers to adapt irrigation strategies for maximum crop yield and water use efficiency. A field trial was conducted to observe the effects of various drip irrigation ratios (IR-0, IR-25, IR-50, IR-75 and IR-100) on water use efficiency (WUE), the irrigation water use efficiency (IWUE), lint yield, yield components and fibre quality at two upland cotton varieties during 2004 and 2005. WUE was found to increase from 0.62 to 0.71 kg m−3 as the irrigation water applied was reduced from 100 % to 75 % of soil water depletion. Deficit irrigation of cotton with drip irrigation at 75 % treatment level (IR-75) did not decrease seed cotton yield and yield components during 2 years, with the exception of the number of bolls in 2005. Among fibre quality parameters, no significant differences in fibre length, fineness, uniformity index and elongation were detected between the 100 % and 75 % irrigation levels in 2005. The results revealed that irrigation of cotton with a drip irrigation method at 75 % level had significant benefits in terms of saved irrigation water without reducing yield, and high WUE indicated a definitive advantage of employing deficit irrigation under limited water supply conditions. 相似文献
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Yilmaz A Kaleta EF 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(9):461-465
Various materials with rough surfaces were tested to determine their suitability for virus carrier tests designed to evaluate virucidal activity of chemical disinfectants. A non-enveloped RNA virus, bovine enterovirus type 1, strain LCR 4 [entero cytopathogenic bovine orphan virus (ECBO)] and an enveloped RNA virus, paramyxovirus type 1 [Newcastle disease virus (NDV), strain Montana] served as test viruses. Experiments with ECBO virus were carried out in four sets, and those with NDV in three sets. In the first set we used poplar wood, frosted glass slides and Sartorius membrane filters. The second set comprised of poplar wood, frosted glass slides, polyamide filters, and cellulose nitrate filters and, in the third set, glass fibre filters and glass fibre pre-filters were added. The fourth test included poplar wood, frosted glass slides, and polyethersulphone ultra filters. Because of their extremely low levels of virus recovery, glass, polyamide, cellulose nitrate and glass fibre filter, glass fibre pre-filter, and polyethersulphone ultra filters are not suitable for sufficient recovery of ECBO virus. Only poplar wood carriers allowed sufficient recovery rates of ECBO virus. In the first and second set of tests, NDV could be sufficiently recovered from poplar wood, glass slides, and polyamide filter. In the third set, the virus recovery from polyamide filter was very low. Poplar wood carrier is recommended as a reliable carrier for the tests with both viruses, but methods for virus recovery must be improved, e.g. by more vigorous and longer shaking or optimizing the ultrasonic treatment. 相似文献
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With the cloning of the alpha-amino-3-hydroxy-5-methyl-4-isaxole propionic acid (AMPA)-type receptor subunits, it is now possible to localize these receptor subunits in the spinal cord. Comparison of the neurokinin 1 receptor distribution with that of non-N-methyl-D-aspartate glutamate receptor subunits (GluR1-4), considered to be AMPA-type, was investigated in rat spinal cord by immunocytochemical methods. Different patterns of immunolabelling were observed with the antibodies to the GluR1, GluR2/3 and GluR4 subunits in the lumbar spinal cord. Immunolabelling with antibodies to both GluR1 and GluR2/3 revealed intensive staining in the dorsal horn, while staining for GluR2/3 and GluR4 was dense in the motor neurons of the ventral horn. These results suggest that in the rat spinal cord AMPA-type receptors vary their composition according to the region where they are expressed. Neurokinin-1-receptor-expressing neurons in the dorsal horn do not appear to express the GluR4 subunit, however, whether they express the GluR1, GluR2/3 receptors subunits could not be determined. 相似文献
6.
The incidence, severity and distribution of six viruses infecting capsicum were determined in the main growing areas of Turkey during the 2004 growing season. The surveys covered 50 randomly selected capsicum fields from four different areas in south-east Anatolia and the eastern Mediterranean region. 515 samples were individually collected and tested by DAS-ELISA for Cucumber mosaic cucumovirus (CMV), Alfalfa mosaic alfamovirus (AMV), Potato X potexvirus (PVX), Potato Y potyvirus (PVY), Pepper mild mottle tobamovirus (PMMoV) and Tobacco etch potyvirus (TEV). 64.8% of ELISA-tested capsicum samples (334 out of 515) were infected by one (41.7%) or more (23.1%) viruses. PVY was the most widespread (26.4%), followed by PVX (25.8%), AMV (25.2%), TEV (23%), PMMoV (9.1%) and CMV (8.3%). Surprisingly high AMV infection was found in three areas (Kahramanmaraş, Şanlıurfa and Gaziantep) where AMV is reported for the first time in this study. However, AMV was not detected in Hatay. PMMoV is another new virus, in all the tested areas. 相似文献
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One of the problems encountered in the extrusion of plastic profiles is unbalanced flow at the die exit. It causes deformation of the extrudates at ambient and precludes the material transition through remaining stages of production process (calibration, cooling sections etc). In this paper, geometric parameters of a profile extrusion die are optimized using several objective function definitions by Simulated Annealing-Kriging Meta-Algorithm. Objective functions are defined based on the uniformity of velocity distribution at the die exit. For this, Computational Fluid Dynamics (CFD) simulations are performed for N=70 die geometries. Appropriate geometric parameters (t and L) of the die are variables for the optimization problem. 相似文献
9.
In this study, energy use patterns and the functional relationship between energy inputs and output for pomegranate production were investigated in Antalya province in Turkey. It further objective to identify greenhouse gas (GHG) emissions in pomegranate production. Data were obtained from 75 farms using face-to-face interview method. The results indicated that 50,605.5?MJ ? ha?1 of total energy input was required for 76,252.3?MG ? ha?1 pomegranate energy output. 1.51 unit energy output was provided by using 1 unit energy input. 1 unit energy output and 1?kg pomegranate require 0.66 unit and 2.57?MJ energy input, respectively. The average CO2 emission amounts were also calculated to be 1.73?t CO2 per hectare and 88.1?kg CO2 per 1000?kg pomegranate production. Electricity, fertilizers and pesticides were the highest contributors to GHG emissions. Both total energy input usage and GHG emission amounts have been found to be decreasing as the farm size increases. Increasing scale of pomegranates orchards will not only increase energy efficiency and productivity but also decrease environmental pollution and damages. The regression analysis revealed that, excessive use of machinery and fuel inputs results in a decline in energy production in pomegranate. 相似文献
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