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High voltage electron microscopy (HVEM) and HVEM tomography of selectively stained cell processes in the neostriatum have offered an alternative to serial thin section reconstruction for accurate 3-D visualization and measurement of axons, dendrites, and dendritic spines. Tissue preparation is simple and rapid, allowing examination of large numbers of(More)
Nitrogen is a dominant regulator of vegetation dynamics, net primary production, and terrestrial carbon cycles; however, most ecosystem models use a rather simplistic relationship between leaf nitrogen content and photosynthetic capacity. Such an approach does not consider how patterns of nitrogen allocation may change with differences in light intensity,(More)
Photosynthetic capacity, determined by light harvesting and carboxylation reactions, is a key plant trait that determines the rate of photosynthesis; however, in Earth System Models (ESMs) at a reference temperature, it is either a fixed value for a given plant functional type or derived from a linear function of leaf nitrogen content. In this study, we(More)
Landscape attributes that vary with microtopography, such as active layer thickness (ALT), are labor intensive and difficult to document effectively through in situ methods at kilometer spatial extents, thus rendering remotely sensed methods desirable. Spatially explicit estimates of ALT can provide critically needed data for parameterization,(More)
We present a semi-automated approach to recognize and hierarchically partition water-body regions of Arctic tundra landscape, such as streams, inundated drained thaw lake basins and ice wedge polygon ponds, in high resolution satellite imagery. The approach integrates the active contours without edges (ACWE) technique and shape-based recognition, and(More)
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