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The study involves an object-based segmentation method to extract feature changes in tropical rainforest cover using Landsat image and airborne LiDAR (ALS). Disturbance event that are represents the changes are examined by the classification of multisensor data; that is a highly accurate ALS with different resolutions of multispectral Landsat image. Disturbance Index (DI) derived from Tasseled Cap Transformation, Normalized Difference Vegetation Index (NDVI), and the ALS height are the variables for object-based segmentation process. The classification is categorized into two classes; disturbed and non-disturbed forest cover using Nearest Neighbor (NN), Random Forest (RF) and Support Vector Machine (SVM). The overall accuracy ranging from 88% to 96% and kappa ranging from 0.79 to 0.91. Mcnemar's test p-value (<0.05) is applied to check the classification for each method used which is RF 0.03 and SVM 0.01. The accuracy increases when the integration of ALS in Landsat image (SpectralLandsat; and SpectralLandsat + HeightALS). [ABSTRACT FROM AUTHOR]

Fire in the forested tropics has profound environmental, economic, and social impacts at multiple geographical scales. Causes of tropical fires are widely documented, although research contributions are from many disciplines, and each tends to focus on specific facets of a research problem, which might limit understanding of fire as a complex social-ecological system. We conducted a systematic review to (1) examine geographic and methodological focus in tropical fire research; (2) identify which types of landholders are the focus of the research effort; (3) test for a research method effect on the variables, e.g., socio-political, economic, and climatic, identified as causes of and proposed management solutions to tropical fire; and (4) examine relationships between causal factors and proposed solutions. Results from 51 studies show distinct geographic and methodological tendencies in the literature. Few studies explicitly identify landholder types, and no social studies focused on large-landholders. Multiple drivers and potential solutions to preventing fire are identified and the research approach adopted had the strongest influence on the socioeconomic, direct fire management and landscape characteristics variables. There was an overall mismatch between identified cause and proposed management solution. These findings indicate that mixed method approaches are imperative to understanding the coupled human-nature system of fire and to improve rural development and management strategies to curtail tropical fire spread. [ABSTRACT FROM AUTHOR]

Abstract: This study simulated the economic and environmental performance of three types of wheat sown into soils with three initial N contents and using ten different fertiliser management strategies. The Agricultural Productions Systems Simulator (APSIM) was used to model crop yields for which gross margins were estimated and a Bayesian Network used to estimate environmental risk. Based on economic and environmental considerations, it would appear that for low N soils more than 10kgN/ha is needed at sowing. For soils with medium to high N, short and medium season wheat varieties need only 10kgN/ha, while long season varieties require >10kgN/ha, at sowing. Additional N fertiliser can be applied after sowing to maximise gross margins, taking into account potential crop yield and seasonal conditions. Interestingly, the study suggests that where farmers increase their gross margins they are improving their environmental performance. This is counter intuitive as it implies N fertiliser applications can lessen N exports. This results from the enhanced water uptake by the crop outweighing the adverse effects of increased N availability. It would appear that flexible cropping systems that maximise crop potential with minimum sowing N, maximise both economic and environmental performance. [Copyright &y& Elsevier]

Abstract: The structures of xyloglucans from several plants in the subclass Asteridae were examined to determine how their structures vary in different taxonomic orders. Xyloglucans, solubilized from plant cell walls by a sequential (enzymatic and chemical) extraction procedure, were isolated, and their structures were characterized by NMR spectroscopy and mass spectrometry. All campanulids examined, including Lactuca sativa (lettuce, order Asterales), Tenacetum ptarmiciflorum (dusty miller, order Asterales), and Daucus carota (carrot, order Apiales), produce typical xyloglucans that have an XXXG-type branching pattern and contain α-d-Xylp-, β-d-Galp-(1→2)-α-d-Xylp-, and α-l-Fucp-(1→2)-β-d-Galp-(1→2)-α-d-Xylp- side chains. However, the lamiids produce atypical xyloglucans. For example, previous analyses showed that Capsicum annum (pepper) and Lycopersicon esculentum (tomato), two species in the order Solanales, and Olea europaea (olive, order Lamiales) produce xyloglucans that contain arabinosyl and galactosyl residues, but lack fucosyl residues. The XXGG-type xyloglucans produced by Solanaceous species are less branched than the XXXG-type xyloglucan produced by Olea europaea. This study shows that Ipomoea pupurea (morning glory, order Solanales), Ocimum basilicum (basil, order Lamiales), and Plantago major (plantain, order Lamiales) all produce xyloglucans that lack fucosyl residues and have an unusual XXGGG-type branching pattern in which the basic repeating core contains five glucose subunits in the backbone. Furthermore, Neruim oleander (order Gentianales) produces an XXXG-type xyloglucan that contains arabinosyl, galactosyl, and fucosyl residues. The appearance of this intermediate xyloglucan structure in oleander has implications regarding the evolutionary development of xyloglucan structure and its role in primary plant cell walls. [Copyright &y& Elsevier]

Background: Nutrient levels are known to influence the development of osteoarthritis (OA), presumably by modulating levels of matrix biosynthesis and degradation. These processes may be affected by ascorbic acid (AA), an antioxidant which acts as a cofactor for numerous biochemical reactions and is essential for post-translational modifications of collagen. In this study we examined the expression of SVCT2, the only known Sodium coupled vitamin C transporter isoform present in articular cartilage, in human articular cartilage explants derived from both normal and osteoarthritis articular cartilage.Methods: OA1 and OA3 human articular cartilage was carefully dissected and macroscopically graded for degeneration via the Collins scale. The tissue samples were histologically examined by Hematoxylin and Eosin and Safranin O and Fast Green staining. SVCT2 expression analysis was performed at mRNA level by quantitative real time PCR and at a protein level by immunohistochemistry.Results: Our quantitative real time PCR showed marked variation in the expression of SVCT2 in human osteoarthritic articular cartilage. SVCT2 expression was significantly down-regulated (p = 0.0001) in the Collins grade 3 (OA3) compared to Collins grade 1 (OA1) tissue. Furthermore, slides stained with fluorescent antibodies to SVCT2 demonstrated greatly reduced fluorescence for the SVCT2 transporter on the chondrocyte plasma membrane in the osteoarthritic tissue samples.Conclusions: These findings demonstrate that the expression of SVCT2 transporter is significantly altered in human osteoarthritic tissues (OA3). The modulation of this transporter could therefore potentially influence the prevention, management and treatment of osteoarthritis. [ABSTRACT FROM AUTHOR]