Our objective is to understand how rates of soil C formation and plant biomass are influenced by changes in plant growth and performance resulting from lowered lignin and altered lignin S/G ratios. A greenhouse study of the effects of altered lignin in SOC formation and plant biomass has been completed as of November 2009. Wild-type (control) and three transgenic aspen lines expressing reduced stem lignin concentrations and/or increased syringyl (S) to guaiacyl (G) ratio lignin were grown in greenhouse mesocosms. Soil was collected from the Colorado Central Plains Experimental Range (CPER) northeast of Fort Collins, Colorado. The Colorado soil is an Olney fine sandy loam (fine-loamy, mixed, superactive, mesic Ultic Haplargrid). Plants at the surface mineral soil up to 5 cm depth were removed and the underlying soil was sampled to a depth of 30 cm. Soils were immediately shipped to Reno, NV. This C4 soil was then used to trace belowground C inputs by the C3 plants into the soil using the 13C natural abundance methods as described in the DOE proposal. Transgenic quaking aspen were generated by the Forest Biotechnology Group at North Carolina State University (NCSU) using Agrobacterium-mediated transformation, the seedlings were then shipped to Reno, NV. …

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"This supplement to the annual Texas Education Agency report on grade-level retention in Texas public schools provides data by district and grade and by district characteristic for the 2007-08 school year."

Annual report of compiled data regarding student retention in Texas public schools, broken down by grade levels, various demographic criteria, and participation in special programs, as well as information regarding data collection and analysis.

Using x-ray computerized tomography (CT), we have characterized the x-ray linear attenuation coefficients (LAC) of a Play Dough{trademark}-like product, Fun Dough{trademark}, designated as PD. Table 1 gives the first-order statistics for each of four CT measurements, estimated with a Gaussian kernel density estimator (KDE) analysis. The mean values of the LAC range from a high of about 2100 LMHU{sub D} at 100kVp to a low of about 1100 LMHU{sub D} at 300kVp. The standard deviation of each measurement is around 1% of the mean. The entropy covers the range from 3.9 to 4.6. Ordinarily, we would model the LAC of the material and compare the modeled values to the measured values. In this case, however, we did not have the composition of the material and therefore did not model the LAC. Using a method recently proposed by Lawrence Livermore National Laboratory (LLNL), we estimate the value of the effective atomic number, Z{sub eff}, to be near 8.5. LLNL prepared about 50mL of the Fun Dough{trademark} in a polypropylene vial and firmly compressed it immediately prior to the x-ray measurements. Still, layers can plainly be seen in the reconstructed images, indicating that the bulk density of the material in the container …

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