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(1-x)BNT-xBT ceramics were prepared by conventional ceramic processing. The determination of the optimized sintering conditions allowed to the production of high density ceramics free from secondary phase. Dielectric and thermal mechanical properties of unpoled samples were determined from cryogenic temperatures to 850 K. The results revealed that the temperature in which an anomaly is observed from the thermal strain curve coincides reasonably with the so-called depolarization temperature characterized by dielectric measurements. While the Burns temperature for traditional relaxors can be determined by dielectric and thermal mechanical measurements and agree with each other, for the (1-x)BNT-xBT ceramics these measurements did not revealed such accordance. [ABSTRACT FROM AUTHOR]

This study evaluated the Propolis product (LLOS) effects on feed intake, dry matter (DM) and nutrients total digestibility, rumen characteristics and microbial efficiency in buffaloes fed a roughage based diet (70% Cynodon spp hay and 30% concentrate). Using a 4×4 latin square design, four crossbred buffalo (Murrah x Jafarabadi) steers (519.0±13.0 kg body weight - BW), were fed four treatments with three LLOS concentrations: Control (no LLOS), LLOS B3+ (0.272 mg/g flavonoid chrysin equivalents), LLOS C1 (0.092 mg/g flavonoid chrysin equivalents), and LLOS C1+ (0.184 mg/g flavonoid chrysin equivalents). Diet formulation was 60% total digestible nutrient (TDN) and 11% crude protein (CP). No difference was observed in DM intake among experimental diets (P>0.05). Steers fed LLOS C1 had greater (P<0.05) coefficients of digestibility for DM (67.2 vs 62.7%), organic matter (OM) (68.1 vs 63.7%), neutral detergent fibre (NDF) (61.7 vs 56.6%), total carbohydrates (TCHO) (67.7 vs 63.2%) and TDN (66.1 vs 62.8%) compared to animals fed the control diet. LLOS C1 provided greatest (P<0.05) short chain fatty acids (SCFA) production (141.89 vs 129.15 μM/mL) and butyric production (16.15 vs 14.05 μM/mL) compared to control. The lowest rumen pH (6.65; P<0.05) was observed in steers fed diets with LLOS C1. No difference (P>0.05) was observed for ammoniacal nitrogen (N-NH3), solid and liquid passage rate and microbial efficiency among treatments. In this study LLOS C1 improved forage diet efficiency in buffalo steers. [ABSTRACT FROM AUTHOR]

This work presents results which help to understand the behaviour of the Normalized Difference Vegetation Index (NDVI) anomalies over the South America continent during the two strongest El Niño events of the last century (1982-1983 and 1997-1998). The data used are parts of a long-term series (July 1981 to December 1999) of calibrated NDVI data derived from National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (NOAA AVHRR) datasets. Special emphasis has been given to the analysis of the response of the major Brazilian vegetation types. This paper introduces an approach that enhances NDVI anomalies relative to the long-term climatology of the region. We find a negative NDVI anomaly for most of the region during the 1982-1983 event, whereas for the 1997-1998 event positive NDVI anomalies were observed over most regions. Only the 'Nordeste' region showed a similar vegetation response for both events. We identify three possible factors that may play a role in the different NDVI responses to the two El Niño events. Firstly, poor intercalibration of sensors may account for some, but not all of the differences. Secondly the response of the vegetation may depend upon the climate conditions prior to the El Niño events. Thirdly, the difference in the onset date and the duration of the mature phase of the two El Niño events, associated with very different Atlantic surface temperatures are shown to have dynamical consequences which may impact upon the vegetation. [ABSTRACT FROM AUTHOR]

Image segmentation based on the shade fraction of a Landsat TM image was effective in measuring the areal extent of Amazonian deforestation. The shade fraction image derived from spectral mixture models was related to the forest canopy structure. Dense tropical forests have a medium proportion of shade within their canopy while deforested areas (bare soil, pasture, and/or regrowth) have a comparatively small proportion. Comparison of image segmentation results with conventional techniques showed visual agreement. Even though additional tests are necessary to validate this approach for large areas, the technical soundness of the approach has been demonstrated. [ABSTRACT FROM AUTHOR]