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41.
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   
42.
Animals used in sport should be treated as required to ensure animal welfare but any such use of medication should also be controlled to ensure integrity. Pharmacokinetic studies on groups of six greyhounds were performed to measure plasma and urine levels of carprofen and firocoxib to inform medication control advice. Using the standard methodology for medication control the Irrelevant Plasma Concentration was determined as 20 and 2 ng/mL for carprofen and firocoxib, respectively. The Irrelevant Urine Concentration was also determined as 0.3 and 2 ng/mL for carprofen and firocoxib, respectively. These Irrelevant Plasma and Urine Concentrations will allow laboratory Screening Limits, Detection Times and Withdrawal Time advice to be determined and publicised by regulators of greyhound racing. The Screening Limits will also inform Recommended Limits of Detection if meat-containing residues of these medications are fed to greyhounds.  相似文献   
43.
Abstract

Acetate, can be considered as an appropriate interface for increasing tolerance to salinity stress in strawberries. Strawberry plants were exposed to different treatments including control (Hoagland solution), salinity (40?mM NaCl), acetic acid (AA) (1?mM), acetic acid (1?mM) + salinity (AAS), ammonium acetate (AA) (1?mM), ammonium acetate (AM) (1?mM) + salinity (AMS), ammonium carbonate (AC) (0.5?mM), and ammonium carbonate (0.5?mM) + salinity (ACS) and put them in hydroponic system. The results indicated that salinity reduced shoot dry weight about 80.12% when compared with untreated control plants. That in comparison to acetate treatments, this reduction was 47.13 and 48.77% in AAS and AMS, respectively. Leaf area was decrease 59% in salinity treatment but this reduction was 14% in AAS. The AAS and AMS were most effective in increasing fruit yields (35.93 and 52.16?g per plant, respectively) in comparison to salinity treatment alone (27.23?g per plant) condition. In saline conditions, the highest amount of soluble carbohydrate was observed in AMS treatment (9.67?mg g?1 DW) that there was no significant difference with AAS treatment. Increase in Na+ and Cl? accumulation in shoots and decreased in K+ in saline condition were observed. The highest amount of potassium was observed in acetate treatments. The present results have demonstrated that acetate could improve tolerance to the salinity, yield and plants growth in strawberry. But, in comparison to AA and AM treatments, better results were observed in AA treatment in both salinity and non-salinity conditions.  相似文献   
44.
Genetic Resources and Crop Evolution - The pomegranate fruit is one of the most important horticultural products due to the presence of polyphenols, anti-oxidant and anti-fungal compounds. In the...  相似文献   
45.
Genetic Resources and Crop Evolution - Climate change may cause a significant decline in winter chill over the coming decades and is becoming an important issue for walnut (Juglans regia L.)...  相似文献   
46.
The response of faba bean Vicia faba (Giza 2 variety) towards soaking conditions differed greatly since the absorbed quantities of water (either by the whole or the decorticated forms) are a function of their chemical constituents. On the other hand, 28.45% of the total vicine (vicine + convicine) present in the whole faba bean samples was extracted after soaking for 72 h at room temperature. Subsequently, other soaking mediums, i.e., 0.5% sodium carbonate and/or 1% acetic acid were used in an attempt to increase the level of vicine elimination. Percentage removal of total vicine in whole faba bean was higher in the acidic (61.31%) than the alkaline (38.40%) medium under the conditions tested, i.e., at room temperature for 72 hours. The rates of vicine + convicine elimination in decorticated faba bean for the acidic acid and alkaline soaking media were 78.46 and 79.13%, respectively. The solubility ratio of total vicine relative to soaking solutions (H2O:Na2CO3:Acetic acid) was 1:1.35:2.16 in the whole broad bean and 1:2.41:2.39 in the decorticated samples. The residual amounts of total vicine (78.33% and 77.27%) present after stewing under normal and under pressure cooking conditions could be expected to be decreased to 30.33% for the former and 29.92% for the later after 72 h of soaking. Regression analysis was used to estimate the theoretical zero point of vicine elimination from faba bean through soaking in 1% acetic acid.  相似文献   
47.

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   
48.
Arbuscular mycorrhizal (AM) fungi alleviate the unfavorable effects of salinity stress on plant growth. A pot study was conducted to determine the effects of AM fungi and salt on growth and some physiological parameters of Citrus jambheri rootstock. Four levels of salinity (2, 4, 6, and 8 dS m?1 as NaCl) and three mycorrhizal treatments (Glomus etunicatum, Glomus intraradices and non-mycorrhizal (NM) control) were used. As salinity increased, all measured characteristics of plants after 4.5-month growth except Na uptake, proline content, and electrolyte leakage decreased. Shoot dry weight and K uptake were significantly higher in G. intraradices-colonized seedlings than NM controls at all salinity levels. Root dry weight and shoot P uptake were significantly higher in G. etunicatum-colonized seedlings than NM controls at all salinity levels. G. intraradices-colonized seedlings had significantly higher proline content than NM controls and G. etunicatum-colonized seedlings at salinity levels of 4, 6 and 8 dS m?1. The electrolyte leakage percentage was significantly lower in G. intraradices-colonized seedlings than NM controls at all salinity levels. The data demonstrated that mycorrhizal citrus seedlings exhibited greater tolerance to salt stress than NM seedlings and the enhanced proline content seems to be one of the mechanisms involved.  相似文献   
49.
Journal of Plant Diseases and Protection - Potato, (Solanum tuberosum), is one of the most common and important food sources for humans. It is not only essential as a food source but also has many...  相似文献   
50.
Background:The methylotrophic yeast Pichia pastoris is an appealing production host for a variety of recombinant proteins, including biologics. In this sense, various genetic- and non-genetic-based techniques have been implemented to improve the production efficiency of this expression platform. Los1 (loss of supression) encodes a non-essential nuclear tRNA exporter in Saccharomyces cerevisiae, which its deletion extends RLS. Herein, a los1-deficient strain of P. pastoris was generated and characterized. Methods:A gene disruption cassette was prepared and transformed into an anti-CD22-expressing strain of P. pastoris. A δ los1 mutant was isolated and confirmed. The drug sensitivity of the mutant was also assessed. The growth pattern and the level of anti-CD22 ScFv expression were compared between the parent and mutant strains.Results:The los1 homologue was found to be a non-essential gene in P. pastoris. Furthermore, the susceptibility of los1 deletion strain to protein synthesis inhibitors was altered. This strain showed an approximately 1.85-fold increase in the extracellular level of anti-CD22 scFv (p < 0.05). The maximum concentrations of total proteins secreted by δ los1 and parent strains were 125 mg/L and 68 mg/L, respectively.Conclusion:The presented data suggest that the targeted disruption of los1 homologue in P. pastoris can result in a higher expression level of our target protein. Findings of this study may improve the current strategies used in optimizing the productivity of recombinant P. pastoris strains. Key Words: Aging, Longevity, Pichia pastoris, Recombinant proteins  相似文献   
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