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Seyed Armin Hashemi Sasan Babaei Kafaki Asadollah Mataji 《Journal of Sustainable Forestry》2013,32(7):697-712
We selected 15 beech trees (Fagus orientalis) from the study area in a mountainous region from 520 to 1310 m above sea level. Ground observations of the beech tree growth process from January to December 2004 in 7- to 15-day intervals were performed both visually and by measuring leaf chlorophyll concentration (chlorophyll meter SPAD-502). Results for the regression analysis showed that the leaved period positively correlated with the air temperature (r?=?.894). Anthesis and SPAD measurements have a negative relationship with air temperature and as temperature increases they appear earlier in the year. Anthesis and SPAD measurements had correlation coefficients of r?=??.883 and r?=??.855, respectively. The anthesis and bud bursting and leaf tip appearance have a negative relationship with increasing altitude from sea level and as altitude increases they appear later in the year. To make phenological events in deciduous broadleaf forests recognizable, we used a seasonal 8-day composite Moderate Resolution Imaging Spectroradiometer/Normalized Difference Vegetation Index (MODIS/NDVI). Prior to leaf expansion, NDVI increased from the 109th day of the year or earlier. Existence of the evergreen plants (Ruscus hyrcanus) on the ground and snow-melting exert an influence on inconsistency of phenology monitoring of MODIS/NDVI images. Regression analysis showed that there is a positive relationship between NDVI and SPAD measurements (chlorophyll content) in beech trees. 相似文献
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Thromboelastographic Clot Characteristics of Autologous Equine Blood Products After Activation by Autologous Thrombin,Bovine Thrombin,or Calcium Chloride
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Objective
To compare clotting efficiency of platelet‐rich plasma (PRP) and concentrated platelet‐poor plasma (cPPP) to citrated whole blood after activation by autologous thrombin, bovine thrombin, or calcium chloride (CaCl2).Study Design
Experimental study.Animals
Healthy adult horses (n = 6).Methods
PRP and cPPP were prepared by commercial devices. Using thromboelastography, clotting variables were compared after activation of citrated autologous blood, PRP, and cPPP by autologous thrombin, bovine thrombin, or CaCl2, respectively.Results
PRP had the greatest clot strength and quickest clot rate, whereas cPPP had the weakest clot strength, slowest clot rate, and longest clot initiation time. Bovine thrombin resulted in the shortest clot initiation time, quickest clot rate, and was similar to CaCl2 for greatest clot strength. CaCl2 also resulted in the longest clot initiation time and time to reach maximum clot strength. Autologous thrombin resulted in the lowest clot strength.Conclusion
When combined with either bovine thrombin or CaCl2, PRP provided the best combinations for clinical use. Autologous thrombin was suboptimal, but could be an autologous alternative for clinical application. As prepared here, cPPP had inefficient clotting, but may be sufficient for plasma spray indications. 相似文献3.
Integrated use of GIS,remote sensing and multi-criteria decision analysis to assess ecological land suitability in multi-functional forestry 总被引:1,自引:0,他引:1
The Zagros forests are a treasure of valuable oak forests, but they have been severely degraded from long-term misuse. Geographic information systems (GIS) and multi-criteria decision analysis (MCDA) have been increasingly used to improve the management of vulnerable ecosystems to prevent further degradation and increase the sustainability of land use. This study presents a methodology to assess land suitability using remote sensing (RS) to obtain wall-to-wall data for the calculations, GIS to analyze the data, and MCDA to rank alternative land uses. The criteria and subcriteria affecting the suitability of land for different uses were identified and weighted using an analytic hierarchy process. Variables used as subcriteria were assessed using satellite data and other sources of information such as existing maps and field surveys. Numerical values for the subcriteria were classified, and each class was given a priority rating according to expert judgments. Based on the ratings and weights of the subcriteria, a priority map was created for each land use using the weighted linear combination method. The priority maps for different land uses were overlaid to obtain a preliminary land use map, which often indicated several simultaneous land uses for the same location. The preliminary map was further edited by removing unrealistic, mutually exclusive land-use combinations. The study tested and demonstrated the potential of integrating RS, GIS and MCDA techniques for solving complicated land allocation problems in forested regions using a scientifically sound and practical approach for efficient and sustainable allocation of forestland for different uses. 相似文献
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