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31.
Khabat KHOSRAVI Phuong T. T. NGO Rahim BARZEGAR John QUILTY Mohammad T. AALAMI Dieu T. BUI 《土壤圈》2022,32(5):718-732
Water infiltration into soil is an important process in hydrologic cycle; however, its measurement is difficult, time-consuming and costly. Empirical and physical models have been developed to predict cumulative infiltration (CI), but are often inaccurate. In this study, several novel standalone machine learning algorithms (M5Prime (M5P), decision stump (DS), and sequential minimal optimization (SMO)) and hybrid algorithms based on additive regression (AR) (i.e., AR-M5P, AR-DS, and AR-SMO) and weighted instance handler wrapper (WIHW) (i.e., WIHW-M5P, WIHW-DS, and WIHW-SMO) were developed for CI prediction. The Soil Conservation Service (SCS) model developed by the United States Department of Agriculture (USDA), one of the most popular empirical models to predict CI, was considered as a benchmark. Overall, 154 measurements of CI (explanatory/input variables) were taken from 16 sites in a semi-arid region of Iran (Illam and Lorestan provinces). Six input variable combinations were considered based on Pearson correlations between candidate model inputs (time of measuring and soil bulk density, moisture content, and sand, clay, and silt percentages) and CI. The dataset was divided into two subgroups at random:70% of the data were used for model building (training dataset) and the remaining 30% were used for model validation (testing dataset). The various models were evaluated using different graphical approaches (bar charts, scatter plots, violin plots, and Taylor diagrams) and quantitative measures (root mean square error (RMSE), mean absolute error (MAE), Nash-Sutcliffe efficiency (NSE), and percent bias (PBIAS)). Time of measuring had the highest correlation with CI in the study area. The best input combinations were different for different algorithms. The results showed that all hybrid algorithms enhanced the CI prediction accuracy compared to the standalone models. The AR-M5P model provided the most accurate CI predictions (RMSE=0.75 cm, MAE=0.59 cm, NSE=0.98), while the SCS model had the lowest performance (RMSE=4.77 cm, MAE=2.64 cm, NSE=0.23). The differences in RMSE between the best model (AR-M5P) and the second-best (WIHW-M5P) and worst (SCS) were 40% and 84%, respectively. 相似文献
32.
Tony Hadibarata Abdull Rahim Mohd Yusoff Risky Ayu Kristanti 《Water, air, and soil pollution》2012,223(8):4669-4677
The decolorization of the recalcitrant dye Remazol Brilliant Blue R (RBBR) by the culture filtrate of Polyporus sp. S133 and the effect of various environmental factors were investigated. Both biodegradation and biosorption were playing an important role in bioremoval mechanisms. The highest biosorption of RBBR in Polyporus sp. S133 was shown by all carbon sources such as sucrose, glucose, fructose, and starch. No biosorption was shown by the addition of aromatic compounds and metal ions; 97.1?% RBBR decolorization was achieved in 120-rpm culture for 96?h, as compared to 49.5?% decolorization in stationary culture. Increasing the shaking rotation of the culture to more than 120?rpm was proven to give a negative effect on decolorization. The highest production of laccase was shown at pH 4 and constantly decreases when the pH level increases. The addition of glucose, ammonium tartrate, Cu2+, and protocatechuic acid was the suitable environmental condition for RBBR decolorization. There was a positive relationship between all environmental conditions and laccase production in the decolorization of RBBR. 相似文献
33.
Shadi Eftekharmanavi Rahim Peyghan Mehdi Soltani Masoud Ghorbanpoor najafabadi 《Aquaculture Research》2020,51(9):3479-3487
The outer membrane protein of Aeromonas hydrophila is a potential candidate for vaccine development. In this study, after cloning and expression of ompTS, 270 common carp, weighing 44 ± 5.7 g divided into five groups, were injected intraperitoneally twice with 3‐week intervals. Groups included the following: PBS, PBS plus Freund's adjuvant, recombinant protein, recombinant protein plus Freund's adjuvant and 20 fish as negative control. Two weeks after the second injection, 30 fish of each group were challenged with a dose of 2 × LD50 of Aeromonas hydrophila and RPS was measured. The antibody level was measured using ELISA test. The protection of recombinant protein in the immunized fish with and without adjuvant, respectively, was about 82.61% and 78.26% (the protection of recombinant protein electroeluted from an SDS–PAGE with and without adjuvant, respectively, was about 78.62% and 69.57%). The average of antibody level in recombinant protein with and without adjuvant was significantly higher than the PBS group (p < .05). The ability of recombinant ompTS to increase the antibody level and to protect the fish from challenge by A. hydrophila demonstrated that recombinant ompTS protein injection can be used to immunize common carp against A. hydrophila infection. 相似文献
34.
针对常规悬浮速度理论值与测试值偏差大的问题,该研究以常规悬浮速度理论为基础,通过量纲分析法和力平衡原理,建立籽棉团物理属性与阻力系数之间的关系,提出一种轻软可压缩颗粒悬浮速度理论模型。在棉田测试单颗棉桃完全开裂时所含籽棉团直径,确定气力输棉管道最小直径,并通过管流雷诺数和绕流雷诺数计算确定阻力系数。用体积法测试籽棉团密度,用等密变径法制备6种不同密度、18种不同直径的球形籽棉团试样并进行悬浮速度试验测试。结果表明,单颗棉桃全开裂时直径变化范围在38~54 mm之间,此范围内管流和绕流雷诺数都大于500,阻力系数为0.44;籽棉团松散密度范围为20~90 kg/m3,半压实密度范围为90~220 kg/m3;籽棉团悬浮速度测试值从直径比(籽棉团直径与管道直径之比)大于0.6开始与常规悬浮速度理论值偏离,直径比等于1时籽棉团悬浮速度测试值不等于0。采用该研究提出的理论算法时,得到的籽棉团悬浮速度分布特征和大小与测试结果基本吻合,平均相对误差为4.6%,并通过方差分析验证了该研究提出的理论算法的有效性。这为籽棉、羊毛和驼绒等轻软可压缩物料的气力输送系统和装置的改进设计提供理论算法。 相似文献
35.
Inheritance of resistance to sunflower downy mildew races 1, 2 and 3 in cultivated sunflower 总被引:1,自引:0,他引:1
Sunflower downy mildew (SDM) caused by Plasmopara halstedii, is a major disease of sunflower. Eleven resistance genes have been identified, but allelic relationships among these genes are not clear. This study examined the inheritance and allelic relationships of genes conferring resistance to SDM races 1, 2 and 3 (virulence phenotypes 100, 300 and 700, respectively) and confirmed a twelfth resistance gene. Three USDA Plant Introductions, AMES 3235, PI 497250, and PI 497938, and three released lines, RHA 266, RHA 274 and DM‐2 were studied. RHA 266 has only the Pl1 gene for race 1 resistance. Digenic inheritance of resistance was found in AMES 3235, PI 497250, and RHA 274. These lines have the Pl1 and Pl12 genes, conferring resistance to race 1, and the Pl2 and Pl11 genes, conferring resistance to race 2. DM‐2 and PI 497938 have Pl12 (but not Pl1 for resistance to race 1, the Pl12 gene (but not the Pl2) for resistance to race 2, and Pl5 for resistance to race 3. These resistance genes will serve as a foundation for future gene designations and genetic diversity studies of resistance to SDM. 相似文献
36.
Al-Mashreki MH Akhir JB Abd Rahim S Desa KM Rahman ZA 《Pakistan journal of biological sciences: PJBS》2010,13(23):1116-1128
In the present study, an assessment of land suitability potential for agriculture in the study area of IBB governorate, Republic of Yemen has been conducted through close examination of the indicators of land characteristics and qualities. The objective of this study is to evaluate the available land resource and produce the potential map of the study area. Remote sensing data help in mapping land resources, especially in mountainous areas where accessibility is limited. Satellite imagery data used for this study includes data from multi-temporal Landsat TM which dated June 2001. The parameters taken into consideration were 16 thematic maps i.e., slope, DEM, rainfall, soil, land use, land degradation as well as land characteristics maps. Satellite image of the study area has been classified for land use, land degradation and soil maps preparation, while topo sheet and ancillary data have been used for slope and DEM maps and soil properties determination. The land potential of the study area was categorized as very high, high, moderate, low and very low by adopting the logical criteria. These categories were arrived at by integrating the various layers with corresponding weights in a Geographical Information System (GIS). The study demonstrates that the study area can be categorized into spatially distributed agriculture potential zones based on the soil properties, terrain characteristics and analyzing present land use. This approach has the potential as a useful tool for guiding policy decision on sustainable land resource management. 相似文献
37.
Roya Rahnama Rahim Peyghan Masoud Reza Seyfi Abad Shapouri Anahita Rezaie Nastaran Shahbazian 《Aquaculture Research》2019,50(2):474-482
Viral haemorrhagic septicaemia (VHS) is one of the most important viral diseases in rainbow trout that has caused great losses to Iranian rainbow trout aquaculture industry in the last 3 years. Therefore, rapid and reliable diagnosis of VHS virus infections is of great importance. An enzyme linked immunosorbent assay (ELISA) method was performed to study serum antibodies against viral haemorrhagic septicaemia virus (VHSV) using recombinant fragments of their N protein. For this purpose, the virus was first isolated from an infected farm. A part of the nucleocapsid (1–505 bp) gene was amplified by RT‐PCR using specific primers. The amplified fragment was ligated to pMALc2x vector and transferred to DH5α strain of Escherichia coli. Then, recombinant plasmids were tested for protein expression in E. coli Rosetta strain. SDS‐PAGE analysis indicated the production of a recombinant protein with an expected molecular weight of 61 KDa. Analysis of trout serum samples from seven previously infected farms and two VHS free farms showed that the designed ELISA method was effective in diagnosing the infected fish. The results revealed that the developed serological assay using designed ELISA based on recombinant protein (N) has the potential to be used in monitoring studies and to determine the prevalence of VHS in rainbow trout farms. The present data allow evaluating the levels of nonneutralizing antibodies without crude virus preparations. 相似文献
38.
Co-evolution of wheat and its devastating pathogen Mycosphaerella graminicola (anamorph Septoria tritici), the causal agent of septoria tritici blotch, a foliar disease of wheat, is suggested to occur in Fertile Crescent as their center of origin and, thus, interaction between pathogen virulence and host resistance is important subject to be addressed. We have investigated resistance spectra of 54 wheat genotypes including a set of differentials carrying known resistance genes and virulence patterns of 14 M. graminicola isolates at seedling stage under controlled environmental conditions. The isolates were collected in Iran from five provinces. Diversity in virulence and aggressiveness was observed among the isolates from four provinces. Isolates collected from Golestan province were virulent to all wheat genotypes from germplasm of Iran, while specific resistances were identified to the isolates from other provinces. Among wheat genotypes, cvs. Chamran, Morvarid and Hirmand had the greatest number of specific resistances as well as partial resistance. Wheat genotypes of the differential set also differed in their reactions to the isolates. Arina, Flame and TE 9111 were specifically resistant to the greatest number of isolates from different provinces. Most isolates were virulent to the other differentials such as cvs. Shafir, Estanzuela federal and Courtot indicating that extensive adaption of virulence to most of the known resistance genes (Stb) has occurred in these regions. The new sources of resistance to highly virulent isolates from Iran may also be utilized in wheat breeding programs to develop resistant cultivars against pathogen populations in other countries. 相似文献
39.
Shoji Noguchi Abdul Rahim Nik Zulkifli Yusop Makoto Tani Toshiaki Sammori 《Journal of Forest Research》1997,2(3):125-132
Field observations were conducted at Bukit Tarek Experimental Watershed in Peninsular Malaysia to investigate the relationship
between rainfall-runoff responses and variation in soil moisture in a tropical rain forest. Stormflow depended strongly on
the antecedent wetness as represented by the initial runoff rate. Though heavy rains fell in almost every month, the soil
moisture decreased when fair weather was sustained. The soil moisture depleted and became dry at 160 cm depth during occasional
dry spells. During dry conditions, streamflow responded quickly to rain events but declined rapidly after the rain stopped,
and the soil moisture of surface soil (≤20 cm) increased but remained dry at lower depths (≽80 cm). This suggests that the
rain water was mostly retained in the soil and only small proportions appeared as stormflow. As soil moisture conditions became
wetter, the recession limb of the storm hydrograph was more gradual. Stormflow volume increased with increasing soil moisture.
During wet conditions, the soil profile was moist at all parts of the slope. The hydraulic gradient was around 1.0 and there
was downward soil water flux, which followed the pressure gradient. This suggests that subsurface flow from the upper part
of the slope might also be important for stream-flow production. Positive pressures were observed at 10 cm and 160 cm depths
during large storms. The behavior of the subsurface flow might be an important determinant of stormflow. 相似文献
40.
To develop a male sterile line of eggplant (Solanum melongena L.) utilizing the cytoplasm of S. virginianum, an interspecific F1 hybrid between S. virginianum and S. melongena ‘Senryo Nigou’ was continuously backcrossed to S. melongena ‘Uttara’ using ‘Uttara’ as a recurrent pollen parent and four backcross generations, BC1, BC2, BC3 and BC4 were produced. All the plants in backcross generations were anther indehiscent although the F1 hybrid, S. virginianum and S. melongena were dehiscent. Pollen stainability with acetic carmine and in vitro germination ability of pollen in all the backcross progenies were quite lower than those of the parental species. Fruit set percentage, number of seeds per fruit and seed germination rate were high in all the backcross progenies. The present results indicate that anther indehiscent type of functional male sterile line of eggplant could be developed by utilizing the cytoplasm of S. virginianum. PCR-RFLP analysis of chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) were performed to identify the organelle inheritance. The F1 hybrid and all the backcross progenies displayed maternal inheritance of mtDNA. The cpDNA of the examined single BC1 plant exhibited the recombinant cpDNA pattern of the parental F1 hybrid and ‘Uttara’, indicating occurrence of the biparental inheritance of cpDNA. As all the BC2, BC3 and BC4 progenies showed the same recombinant cpDNA patterns of the BC1 plant, the recombinant cpDNA might be stable and harmonize with the nuclear genome of S. melongena. The present male sterile line can contribute to expand the male sterility source of eggplant. 相似文献