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11.
We developed a three-step classification approach for forest road extraction utilizing LiDAR data. The first step employed the IDW method to interpolate LiDAR point data (first and last pulses) to achieve DSM, DTM and DNTM layers (at 1 m resolution). For this interpolation RMSE was 0.19 m. In the second step, the Support Vector Machine (SVM) was employed to classify the LiDAR data into two classes, road and non-road. For this classification, SVM indicated the merged distance layer with intensity data and yielded better identification of the road position. Assessments of the obtained results showed 63% correctness, 75% completeness and 52% quality of classification. In the next step, road edges were defined in the LiDAR-extracted layers, enabling accu- rate digitizing of the centerline location. More than 95% of the Li- DAR-derived road was digitized within 1.3 m to the field surveyed nor- rnal. The proposed approach can provide thorough and accurate road inventory data to support forest management.  相似文献   
12.
Biodegradable edible sub-micron electrospun zein fibers were prepared using acetic acid as solvent. The solution concentration at three levels: 22, 26 and 30 w/v %, the electrospinning voltage at three levels: 10, 20 and 30 kV, the solution flow rate at three levels: 4, 8 and 12 ml/h and the distance between needle tip and collector at three levels: 10, 15 and 20 cm were studied. Central composite design (CCD) was utilized to modeling the effect of electrospinning parameters of zein solution on average fiber diameters and the data were analyzed using response surface methodology (RSM). Coefficient of determination, R2, of fitted regression model was higher than 0.9 for response. The analysis of variance table showed that the lack of fit was not significant for response surface model at 95 %. Therefore, the model for response variable was highly adequate. Results also indicated that the solution concentration had significant influence (P<0.0001) on morphology and diameter of fibers. By increasing the solution concentration, uniform and bead-free fibers were obtained. As the solution concentration was increased, the average fiber diameters were also increased. Furthermore, the electrospinning voltage had significant effect (P<0.0001) on average fiber diameters. By increasing the electrospinning voltage, the average fiber diameters increased. The solution flow rate and the distance between needle tip and collector had no significant influence on the average fiber diameters. According to model optimization, the minimum average fiber diameter of electrospun zein fiber is given by following conditions: 24 w/v % zein concentration, 10 kV of the applied voltage, 10 cm of needle tip to collector distance, and 4 ml/h of solution flow rate.  相似文献   
13.

Background:

Cutaneous leishmaniasis is one of the most important parasitic diseases in humans. In this disease, one of the responsible organisms is Leishmania major, which is transmitted by sandfly vector. There are specific differences in biochemical profiles and metabolite pathways in logarithmic and stationary phases of Leishmania parasites. In the present study, 1H NMR spectroscopy was used to examine the metabolites outliers in the logarithmic and stationary phases of promastigotes in L. major to enlighten more about the transmission mechanism in metacyclogenesis of L. major.

Methods:

Promastigote was cultured, logarithmic and stationary phases were separated by the peanut agglutinin, and cell metabolites were extracted. 1H NMR spectroscopy was applied, and outliers were analyzed using principal component analysis.

Results:

The most altered metabolites in stationary and logarithmic phases were limited to citraconic acid, isopropylmalic acid, L-leucine, ornithine, caprylic acid, capric acid, and acetic acid.

Conclusion:

1H NMR spectroscopy could play an important role in the characterization of metabolites in biochemical pathways during a metacyclogenesis process. These metabolites and their pathways can help in exploiting a transmission mechanism in metacyclogenesis, and outcoming data might be used in the metabolic network reconstruction of L. major modeling. Key Words: Leishmania major, Metabolomics, Principal component analysis  相似文献   
14.
Drought is a worldwide concern and designation of drought stress adaptive mechanisms is one of the main directions in plant physiology and crop breeding. Genotypes diversity can be used to identify effective unexploited genes and pathways. In order to that, the effect of varying terminal drought intensity treatments on physiological and biochemical traits was evaluated in ILC3279, ICCV2 and FLIP9855 C chickpea lines. Well-watered, intermediate and severe drought treatments were applied from flowering till maturity. Photosynthetic efficiency, membrane stability, soluble sugar and proline content, leaf protein profile, and antioxidant enzyme activities were compared on 1st, 3rd, and 5th week after applying stress. Based on the results, it was found that the susceptibility of photosynthetic machinery of ILC3279 was more than others. Tolerant genotypes responded to drought differently; an increase and a decrease in catalase activity have been observed in ICCV2 and FLIP9855 C, respectively. The prominent role of soluble sugars was observed in ICCV2. Expressions of polypeptides 27 and 45 kDa in tolerant lines refer to their possible role in drought stress adaptation. Generally, in spite of significant variability in chickpea lines to cope with drought, lower ascorbate peroxidase activity, higher peroxidase activity, and higher Fv/Fm ratio can be tested as markers of chickpea drought tolerant.  相似文献   
15.
Two experiments were carried out in 2013 and 2014, to investigate changes in grain filling rate (GFR), grain filling duration (GFD) and yield of mung bean in response to salicylic acid (SA) and silicon (Si) under salt stress (0, 3, 6 and 9 dS m?1). In experiment 1, four levels of SA (0, 0.5, 1 and 1.5 mM), but in experiment 2, two levels of SA (0 and 1 mM) and Si (0 and 2 mM) were applied. In experiment 1, GFR, GFD, yield components, biological and grain yields and harvest index were decreased with increasing salt stress. Application of different levels of SA, especially 1 mM, increased GFR, but decreased GFD. In experiment 2, GFD under salinity was shorter than that under non-saline condition, resulting in comparatively smaller grains. Application of Si and particularly SA accelerated grain development under all salinity treatments. The superiority of SA treated plants in GFR, grain weight and grains per plant resulted in greater grain yield per plant under saline and non-saline conditions.  相似文献   
16.
The comparative responses of certain biochemical and physiological characteristics to salinity were studied in 4 cultivars of sugar beet (Beta vulgaris L.) plants. Eight weeks old plants were treated with NaCl at 0, 25 and 50 mM in nutrient solutions. Plants were grown under controlled environment and harvested after 3 weeks for measurements of biochemical and physiological parameters. Results showed that in 25 mM NaCl for cultivars of ET5 and C3-3, soluble sugars in leaves, photosynthetic rate and growth parameters were significantly increased as compared to those of other cultivars. In 50 mM NaCl photosynthetic rate and soluble sugars were significantly increased only in ET5 cultivar as compared with those of others. Results indicated that in 25 mM NaCl, ET5 cultivar showed high growth responses and tolerated to 50 mM NaCl.  相似文献   
17.
BACKGROUND: Evidence supports the involvement of nitric oxide (NO) in a variety of male reproductive processes such as spermatogenesis, spermiogenesis, sperm motion, sperm metabolism and sperm capacitation. However, low concentration of NO is essential in biology and physiology of spermatozoa, but high amounts of NO is toxic and has negative effects on sperm functions. On the other hand, it is established that high amounts of NO have detrimental effects on DNA. The integrity of sperm DNA is an important factor in successful fertility and embryo development. It is hypothesized that supra physiological concentrations of NO in seminal plasma cause sperm DNA damage. The aim of this study was to determine sperm DNA damage by comet assay and its correlation with NO level in seminal plasma of fertile and infertile men. METHODS: Semen samples were collected from 45 patients and 70 healthy donors. The stable metabolites of NO (nitrite and nitrate) in seminal plasma were measured by Griess assay and DNA damage was determined using single cell gel electrophoresis (comet) assay method. RESULTS: The NO concentration in the seminal plasma of infertile males was significantly higher than fertile males (5.74+/-1.01 microM/L vs. 3.88+/-0.53 microM/L). There was a significant positive correlation between the NO concentration and sperm DNA comet value in infertile males (P<0.01, R=0.598). CONCLUSION: These results indicate that the overproduction of NO in genital tract of infertile males has a potential pathogenetic role in the reduction of sperm DNA integrity.  相似文献   
18.
In this paper, poly(amido primary-secondary amine) (PAPSA) as a high capacity polymeric adsorbent was synthesized. Dye removal ability of PAPSA from single and binary systems was investigated. The functional groups of PAPSA were studied using Fourier transform infrared (FTIR). Acid Blue 92 (AB92), Direct Red 23 (DR23), and Direct Red 81 (DR81) were used as model compounds. The kinetic and isotherm of dye adsorption were studied. The effect of operational parameter such as adsorbent dosage, dye concentration, and pH on dye removal was evaluated. It was found that adsorption of dyes onto PAPSA showed Langmuir isotherm. The maximum dye adsorption capacity (Q 0) of PAPSA was 10000 mg/g, 12500 mg/g, and 10000 mg/g for AB92, DR23, and DR81, respectively. Adsorption kinetic of dyes followed pseudo-second order kinetics. Dye desorption tests showed that the dye release of 85 % for AB92, 91 % for DR23 and 89 % for DR81 were achieved in aqueous solution at pH 12. The results showed that the PAPSA as a polymeric adsorbent with high dye removal ability might be a suitable alternative to remove dyes from colored wastewater.  相似文献   
19.
在Postband地区(27°58′4″-28°2′16″N,53°17′34″-53°22′30″E),辨别植物种、植物多样性、生活型及地中海气候、Irano-Torunian和撒哈拉-新店相关植物种。2008年6月至2006年12月间,调查和辨认了29个科,69个属,总计95个种。就物种频度而言,菊科和禾本科是重要的科。按照Raunkiaer's生活型谱系统和利用■2检测,生活型谱表明,年生植物、地面芽植物、高位芽植物、地上芽植物和陷芽植物分别占据全部植物种的47%、31%、12%、7%和3%。在地理分布上,Irano-Torunia地区,拥有最高的频度的29%的物种。结果表明,一年生植物比生活型基准群谱高;高位芽植物比生活型基准群谱低,这与在干旱地区的研究数据相一致。图1表4参50。  相似文献   
20.
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