There has been considerable interest in the recent literature regarding the assessment of post-fire effects on forested areas within the North American boreal forest. Assessing the physical and ecological effects of fire in boreal forests has far-reaching implications for a variety of ecosystem processes – such as post-fire forest succession – and land management decisions. The present paper reviews past assessments and the studies presented in this special issue that have largely been based on the Composite Burn Index and differenced Normalized Burn Ratio (dNBR). Results from relating and mapping fire/burn severity within the boreal region have been variable, and are likely attributed, in part, to the wide variability in vegetation and terrain conditions that are characteristic of the region. Satellite remote sensing of post-fire effects alone without proper field calibration should be avoided. A sampling approach combining field and image values of burn condition is necessary for successful mapping of fire/burn severity. Satellite-based assessments of fire/burn severity, and in particular dNBR and related indices, need to be used judiciously and assessed for appropriateness based on the users’ need. Issues unique to high latitudes also need to be considered when using satellite-derived information in the boreal forest region.

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Impaired eye contact is a unique characteristic of children with CU traits; these impairments are largely independent of maternal behaviour, but associated with psychopathic traits in the fathers. These impairments should be tested for functional significance and amenability to change in longitudinal and treatment studies.

Burn severity strongly influences post-fire vegetation succession, soil erosion, and wildlife populations in the fire-adapted boreal forest and tundra ecosystems of Alaska. Therefore, satellite-derived maps of burn severity in the remote Alaskan landscape are a useful tool in both fire and resource management practices. To assess satellite-derived measures of burn severity in Alaska we calculated the Normalized Burn Ratio (NBR) from pre- and post-fire Landsat TM/ETM+ data. We established 289 composite burn index (CBI) plots in or near four national park areas between 2001 and 2003 in order to compare ground-based measurements of burn severity with satellite-derived values of burn severity. Within the diverse vegetation types measured, a strong linear relationship between a differenced Normalized Burn Ratio (dNBR) and CBI for eight out of the nine fire assessments was found; R2 values ranged from 0.45 to 0.88. The variations in severity among four pre-fire vegetation types were examined and a significant difference in the average dNBR and average CBI values among the vegetation types was found. Black spruce forests overall had the strongest relationship with dNBR, while the high severity white spruce forests had the poorest fit with dNBR. Deciduous forests and tall shrub plots had the lowest average remotely sensed burn severity (dNBR), but not the lowest ground severity among the vegetation types sampled. The tundra vegetation sampled had the lowest ground severity. Finally, a significant difference was detected between initial and extended assessments of dNBR in tundra vegetation types. The results indicated that the dNBR can be used as an effective means to map burn severity in boreal forest and tundra ecosystems for the climatic conditions and fire types that occurred in our study sites.

Rab-coupling protein–mediated integrin trafficking promotes filopodia formation via RhoA-ROCK-FHOD3, generating non-lamellipodial actin spike protrusions that drive cancer cell migration in 3D extracellular matrix and in vivo.