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Accurate characterization of variability and trends in forest biomass at local to national scales is required for accounting of global carbon sources and sinks and monitoring their dynamics. Here we present a new remote sensing based approach for estimating live forest aboveground biomass (AGB) based on a simple parametric model that combines high-resolution estimates of leaf area index (LAI) from the Landsat Thematic Mapper sensor and canopy maximum height from the Geoscience Laser Altimeter System (GLAS) sensor onboard ICESat, the Ice, Cloud, and land Elevation Satellite. We tested our approach with a preliminary uncertainty assessment over the forested areas of California spanning a broad range of climatic and land-use conditions and find our AGB estimates to be comparable to estimates of AGB from inventory records and other available satellite-estimated AGB maps at aggregated scales. Our study offers a high-resolution approach to map forest aboveground biomass at regional-to-continental scales and assess sources of uncertainties in the estimates. [ABSTRACT FROM AUTHOR]

Acrylamide is a probable human carcinogen that is found in many roasted and baked foods. This paper describes two sensitive and reliable LC-(ESI)MS/MS methods for the analysis of (1) acrylamide and (2) common acrylamide precursors (i.e., glucose, fructose, asparagine, and glutamine) in raw and roasted almonds. These methods were used to evaluate the impact of roasting temperatures (between 129 and 182 °C) and times on acrylamide formation. Controlling the roasting temperature at or below 146 °C resulted in acrylamide levels below 200 ppb at all roasting times evaluated. Six varieties of almonds collected in various regions of California over two harvest years and roasted at 138 °C for 22 min had acrylamide levels ranging from 117 ± 5 μg/kg (Sonora) to 221 ± 95 μg/kg (Butte) with an average of 187 ± 71 μg/kg. A weak correlation between asparagine content in raw almonds and acrylamide formation was observed (R(2) = 0.6787). No statistical relationship was found between acrylamide formation and almond variety, orchard region, or harvest year. Stability studies on roasted almonds indicated that acrylamide levels decreased by 12.9-68.5% (average of 50.2%) after 3 days of storage at 60 °C. Short-term elevated temperature storage may be another approach for mitigating acrylamide levels in roasted almonds.