The radiocarbon data in the topsoil and
near bedrock indicate that neither microaggregation nor mineral association is important for SOC stability in this soil. At intermediate sampling depths, the mid-sized fraction was the oldest. We believe that this is the result of charcoal accumulation in this fraction, inducing a shift in radiocarbon age. However, near bedrock (100-120 cm), radiocarbon concentration did not differ significantly between fractions, despite greater SOC retention in smaller fractions. In addition, radiocarbon ages at 100-120 cm indicate that charcoal is not present at this depth. We propose that environmental and soil conditions (substrate limitation, water and oxygen availability, and temperature) are responsible for the stabilization of SOC at this depth, where SOC concentrations were very low (0.1-0.3 %). Our results demonstrate that, although fine particles retain more SOC than coarse CCI-779 nmr ones, they do not stabilize SOC in this sandy soil. Instead, environmental (bushfires and climate) and site factors (soil texture and soil mineralogy) control the distribution and stability of SOC throughout the soil profile.”
“Objective: The purpose of this study was to selleck chemicals analyze left systolic ventricular function and
myocardial perfusion characteristics between short one day exercise-rest and long two days gated SPECT (Single Photon Emission Computed Tomography) protocols in patients with ischemic cardiomyopathy (ICM).\n\nMethods: A prospective study of 40 patients (59.6 +/- 8.9 years, 3 women) with IHD (left ventricular ejection fraction (EF) <= 40%) was performed with myocardial perfusion gated SPECT. From 5 to 10 days after a one-day exercise-rest study (gated SPECT-1), patients were called back for a second rest study (gated SPECT-2) in order to compare GSK1838705A mouse EF and differences in perfusion summed rest score (Delta SRS=SRS1-SRS2) and summed difference score (Delta SDS=SDS1-SDS2) between both protocols.\n\nResults: Between
rest-gated SPECT-1 (short protocol) and rest-gated SPECT-2 (long protocol) EF increased (34% vs 37%, P = 0.008) in 26 patients (65%), and in 11 patients (27.5%) the increase was >= 5%. There were no significant differences in clinical and coronary angiography variables between patients with and without increase of the EF >= 5%. In the multivariate analysis, Delta SRS (95% CI: -1.1 to -29.2) and Delta SDS (0.179-1.236) were predictors for this EF increase between both studies.\n\nConclusions: Exercise-rest short protocol can underestimate EF in patients with CM. Stunning but also contamination of rest images by previous exercise images in a short protocol could explain these results. (C) 2009 Elsevier Espana, S.L. and SEMNIM. All rights reserved.”
“In the present work, a facile and efficient route for the synthesis of a series of N-substituted imidazole derivatives is described.