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6篇 您的检索式:作者名="Sefidi"
    题名 作者 年代 出处 被引量
1Over-mature beech trees (Fagus orientalis Lipsky) and close-to-nature forestry in northern Iran显示文摘Oriental Beech is the most important commercial tree species in northern Iran. In recent years wood production companies interested in felling large beech trees for profit have challenged advocates of close-to-nature silviculture who favor conservation. Our study objective was to assess the economic value of over-mature beech trees by relating tree diameter (DBH) to amount of decay. Based on the location of onset of decay, we categorized three types of decay as stump, stem, and crown decay. Trees of greater diameter (age) typically showed greater decay in the stem. Percent of decayed volume, diameter of decayed tissue, and length of decay in tree stems varied between 0.5%?64.3%, 15 cm?75 cm, and 2.0?19.5 m, respectively. With increasing trunk diameter, the proportion of truck decay increased. Red heart and dark red heart constituted 25% and 14.3% of sampled trees, respectively. However, we found no correlation between intensity of stem decay and morphological characteristics of trees. Seedlings were not abundant around the bases of over-mature trees, suggesting that the trees did not contribute to regeneration of the stand. Beech trees of diameter >1 m do not provide valuable round wood for industries and cause to raise wood production costs. We recommend that these trees >1 m DBH should be retained in forest stands because of their low commercial value but high ecological and conservational values such as maintaining biodiversity in forest ecosys-tems.Mostafa Moradi Mohammad R.Marvie Mohadjer Kiomars Sefidi Mahmoud Zobiri Ali Omidi 2012Journal of Forestry Research2012,23,2:5
2Canopy gaps and regeneration in old-growth Oriental beech(Fagus orientalis Lipsky)stands,northern Iran显示文摘Sefidi K Mohadjer M R Mosandl R Copenheaver C A 0,,06:1
3Natural regeneration of oriental beech(Fagus orientalis Lipsky)trees in canopy gaps and under closed canopy in a forest in northern Iran显示文摘For developing nature-based silvicultural practices in a beech forest to promote, abundance, height,vitality, and preferred growth form, regenerated trees growing in gaps were compared with those under closed canopies.A systematic 50×50 m grid was plotted in a beech stand in the Kheyrud Experimental Forest for selecting trees to measure variables in gaps and under closed canopies.Abundance and mean height of regenerated beech trees were significantly higher in closed canopies than in canopy gaps.Beech seedlings with excurrent growth were significantly taller within regeneration patches under closed canopy.Moreover, regenerated trees with high vitality were more abundant in closed canopy areas than in gaps.Thus, beech regeneration should improve under closed canopies; hence, gaps in a near natural forest should be created only after adequate regeneration and appropriate growth under the parent tree in a closed canopy area is ensured.The results of this research have profound implications for the sustainable management of the forest and for ensuring sustainable beech regeneration.The presence of a closed canopy cover likely will reduce potential stresses on oriental beech regeneration.Nasrin Nasiri Mohammad R.Marvie Mohadjer Vahid Etemad Kiomars Sefidi Leila Mohammadi Maryam Gharehaghaji 2018Journal of Forestry Research2018,29,4:1
4A novel monopole antenna for wireless communication systems and UWB application显示文摘Sefidi M Zehforoosh Y Moradi S 0,,08:1
5Adjuvant role of Pseudomonas flagellin for Acinetobacter baumannii biofilm associated protein显示文摘AIM To study immunogenicity of Pseudomonas N terminal flagellin as an adjuvant for Acinetobacter baumannii(A. baumanni) biofilm associated protein(Bap).METHODS The N terminal flagellin gene was amplified. The p ET28a(+) and polymerase chain reaction products weredigested with HindⅢ and Eco R Ⅰ. The ligation of N terminal flagellin into p ET28a(?+) was performed using T4 DNA ligase and was then transformed into Escherichia coli BL21(DE3) as a suitable expression host. p ET28a(?+) vector harboring a conserved region of Bap from our previous work was used. The recombinant proteins were expressed, analyzed by SDS-PAGE method and was purified by affinity chromatography with His-Tag residues followed by confirmation with western blotting. Mice were immunized with recombinant N terminal flagellin and Bap subunits. The immunized animals were intranasally(i.n) challenged with A. baumannii and Pseudomonas aeruginosa(P. aeruginosa).RESULTS The flagellin enhanced the immunogenicity of Bap causing an increase in specific Ig G titers in serum(P < 0.001). Internal organs, i.e., liver, lung and spleen of the BapFlagellin immunized group challenged with A. baumannii showed significantly lower bacterial load compared to the control group. The bacterial loads were studied in internal organs. A. baumannii infected immunized animals with Bap-Flagellin exhibited internal organs with minor bacterial load while P. aeruginosa PAO1 infected group showed heavy bacterial load of(4.3 ± 0.12) × 106,(1.1 ± 0.01) × 106 and(2.2 ± 0.22) × 106 per gram of lungs, liver and spleen respectively. Bacterial loads were detected per gram of lungs, liver and spleen of the mice group immunized with Bap were(1.2 ± 0.06) × 107,(11.1 ± 0.041) × 105 and(3.6 ± 0.42) × 106 respectively. In vivo neutralization assay indicated that all experimental mice groups, except for Flagellin administered group was significantly(P < 0.05) protected against A. baumannii. CONCLUSION These results demonstrate that P. aeruginosa Flagellin as an adjuvant for Bap A. baumannii could be a useful model to evaluate new vaccine against A. baumannii.Mozhgan Derakhshan Sefidi Iraj Rasooli Parviz Owlia Daryush Talei Shakiba Darvish Alipour Astaneh Shahram Nazarian 2016World Journal of Methodology2016,6,3:1
6Comparison of sustainable forest management (SFM) trends at global and country levels: case study in Iran显示文摘Sustainable Forest Management (SFM) is an integral component of sustainable development. Iran is a Near East country with low forest cover. Iran uses 7 criteria and 65 indicators for regional and national monitoring of forest management. We evaluated the status of SFM in Iran, and a location imaging in its path towards SFM was provided by existing validation data and library references for the Criteria and Indicators (C&I) adopted in the Near East, We identify challenges and opportunities associated with SFM in Iran. Although the information to evaluate the trend of SFM in Iran was incomplete, we compiled some information on the basis of C&I. Comparison of some indicators with the values for the rest of the world revealed that the situation in Iran is very different. Although some indicators revealed a better situation in Iran, Iran lags the rest of the world in the implementation of SFM. Iran, like many countries, is trying hard to find ways to sustainably use its forests. Not all C&I for assessment of SFM in Iran have been determined or defined. However, a consistent and comprehensive framework of criteria and indicators to monitor progress towards SFM is being applied. Defining some C&I is still at an early stage.Ghanbari Sajad Kiomars Sefidi 2012Journal of Forestry Research2012,23,2:0
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