Characterization of residual lignin after SO(2)-catalyzed steam explosion and enzymatic hydrolysis of Eucalyptus viminalis wood chips

The lignin component found in both water insoluble (WI) and water and alkali insoluble (WIA) fractions derived from SO(2)-impregnated steam-exploded eucalyptus chips (SEE) was isolated and characterized. Dioxane lignins with a sugar content lower than 2% (w/w) were obtained after each material was treated with commercial cellulases. The C9 formulas of both SEE-WI and SEE-WIA dioxane lignins were C(9)H(6.83)N(0.04)O(2.24)(OCH(3))(1.21)(OH(aro))(0.56)(OH(ali))(0. 77) and C(9)H(8.65)N(0.29)O(1.97)(OCH(3))(0.90)(OH(aro))(0. 46)(OH(ali))(1.02), respectively. The weight-average molecular weight (M(w)) of the SEE-WI lignin corresponded to 3.85 kDa, whereas the SEE-WIA lignin had an M(w) of 3.66 kDa for the same polydispersity of 2.4. The SEE-WIA lignin was shown to be more thermally stable than the SEE-WI lignin, requiring temperatures in the range of 520 degrees C for complete degradation. FTIR and (1)H NMR analyses of both untreated and peracetylated lignin fractions showed that (a) the alkali insoluble lignin contained a relatively higher degree of substitution in aromatic rings per C9 unit and that (b) alkaline extraction removed lignin fragments containing appreciable amounts of phenolic hydroxyl groups.     

Autoregressive spatial analysis and individual tree modeling as strategies for the management of <Emphasis Type="Italic">Eremanthus erythropappus</Emphasis>

The objectives of this study were to apply statistical techniques to discriminate fertilization treatments of Eremanthus erythropappus (DC.) MacLeish. through autoregressive modeling, and to develop individual tree models for diameter and crown area (CA) projection to define management strategies for candeia plantations subjected to different fertilization treatments. This is an important tree species originating from the Brazilian Atlantic Rain forest and Savannah biomes, intensively used in the cosmetic industry. Nonetheless, to date, research has not addressed the management of natural stands or plantations of the species. Our experiment was located in Baependi, Minas Gerais, Brazil, and comprised of four randomized blocks and 13 treatments. The treatments consisted of 12 different regimes of fertilization plus a control. Each sample plot was composed of 50 plants plus two border plants in a planting spacing of 2.5 × 2.0 m and undergoing pruning at 5 and 6 years of age. Starting in the second year, total tree height (H) and circumference (at 1.30 m from the ground or breast height, CBH) were measured every 6 months. Starting in the fifth year CA was measured. Tree growth varied by fertilization strategy. Differences were detected by using an autoregressive approach, considering that standard statistical methods were not powerful enough to detect significant differences. Three growth groups were formed, and maximum growth was obtained for treatment 10 (NPK, 8-28-16). Management guidelines are provided based on individual tree models for different fertilization levels.     

Cellular UV-microspectrophotometric investigations on pine wood ( Pinus taeda and Pinus elliottii) delignification during biopulping with Ceriporiopsis subvermispora (Pilát) Gilbn. & Ryv. and alkaline sulfite/anthraquinone tr

Scanning UV-microspectrophotometry was used to investigate the topochemistry of lignin removal from pine wood (Pinus taeda and P. elliottii) chips during biopulping involving wood treatment with Ceriporiopsis subvermispora (Pilát) Gilbn. & Ryv. followed by alkaline sulfite/anthraquinone delignification. A delignification front starting from the lumen towards the compound middle lamella was clearly observed in micrographs recorded from individual cell wall layers of wood samples biotreated for 30 days. Lignin was removed without cell wall erosion. UV-micrographs of wood samples cooked for a short time (90 min pulping) showed that the S2 of biotreated samples are more homogeneously delignified compared to the S2 of the undecayed controls. Similarly, the compound middle lamella and cell corners are also more delignified in biotreated samples. On the other hand, UV-micrographs of samples cooked for a long time (150 min pulping at 170°C) showed that there are no significant differences in the contents of residual lignin retained in the S2 of undecayed and biotreated wood samples.     

Sugar and ethanol production as a rural development strategy in Brazil: Evidence from the state of São Paulo

Sugar and ethanol production are key components of Brazil’s rural development and energy strategies, yet in recent years sugar production has been widely criticized for its environmental and labor practices. This study examines the relationship between rural development and sugarcane, ethanol, and cattle production in the state of São Paulo. Our results suggest that the value added components of sugarcane production, which include sugar refining and ethanol production, may have a strong positive affect on local human development in comparison to primary agricultural production activities and other land uses. These results imply that sugar production, when accompanied by a local processing industry can stimulate rural development. However, this paper also highlights the significant environmental and social harms generated by the sugar industry at large, which may undermine its development benefits if not addressed.     

Cytogenetic studies in peripheral blood of bovines afflicted by papillomatosis

Ten types of bovine papillomavirus (BPV) have been described and there are reports of viral transmission via blood. The presence of viral DNA in lymphocytes was described to be associated with chromosome instability in these cells. This study presents an evaluation of chromosome instability in short-term peripheral lymphocyte cultures from cows presenting skin papillomatosis, compared with asymptomatic infected animals and non-infected healthy bovines. In a total of 2203 cells, 918 (42%) showed at least one chromosome aberration: 42.7 (± 7.8) in animals with papillomatosis (BPV + W), 40.2 (± 11) in asymptomatic animals (BPV-W) and 4 (± 2) in control animals. Significant differences were found between the infected group (with or without symptoms) and the control group (P < 0.0001). The increased frequencies of chromosome aberrations suggest an interaction between the virus and host cell chromatin.     

Effects of protein sources and inclusion levels on nitrogen metabolism and urea kinetics of Nellore feedlot steers fed concentrate-based diets

Urea recycling occurs in all mammalian species and represents an important source of ruminal nitrogen (N) for ruminants fed protein-restricted diets. However, its importance for cattle fed adequate amounts of protein and energy remains unclear. Six Nellore feedlot steers fed concentrate-based diets were used in a 6 × 6 Latin square design with a 3 × 2 factorial arrangement of treatments to evaluate ruminal fermentation, urea kinetics, and N excretion. Treatments consisted of 3 protein sources (PS: soybean meal plus urea [SU], corn gluten meal [CGM], and dry distillers grains [DDG]) and 2 inclusion levels (PL; 11% and 14%). Steers were adapted to the diets for 14 d followed by 8 d of sample collection. Feed intake, fecal output, and urine production were measured from day 18 to day 22 of each period. Blood samples were collected every 6 h on day 18. [¹⁵N-¹⁵N]-urea was infused into the jugular vein for 82 h over day 19 to day 22, and measurement of ¹⁵N in background (day 18) and enriched feces and urine (day 21) were used to evaluate urea kinetics. To evaluate the incorporation of recycled urea N into microbial protein (MICP), ruminal and duodenal fluid were collected on day 22. Steers fed SU diets had lower (P < 0.05) nitrogen use efficiency (NUE), greater (P < 0.05) urea-N entry rate (UER), and tended (P < 0.10) to have greater gastrointestinal entry rate of urea-N (GER) compared with those fed CGM or DDG. In addition, steers fed SU had greater (P < 0.05) urea-N returned to ornithine cycle (ROC) compared with those fed CGM or DDG. Increasing PL tended (P < 0.10) to increase UER. The proportion of total microbial N from recycled urea-N was greater (P < 0.05) for steers fed CGM compared with those fed SU and also greater for steers fed diets with 11% CP than for those fed with 14% CP. Diets with 11% CP can be used for Nellore feedlot cattle fed concentrate-based diets without negatively affecting intake, digestibility, and ruminal fermentation. Moreover, diets containing rumen undegradable protein (RUP) feed sources (CGM or DDG) compared with diets with SU markedly increased NUE, while maintaining microbial protein (MICP) synthesis. Results from this study suggest that the equation adopted by NASEM (NASEM. 2016. Nutrient requirements of beef cattle. 8th revised ed. Washington, DC: The National Academies Press) was not accurate in estimating the urea-N used for anabolism (UUA) in Nellore feedlot cattle fed concentrate-based diets.     

How good are tropical forest patches for ecosystem services provisioning?

Native forests play an important role regarding ecosystem services related to biodiversity, water, and nutrient cycling, and the intensity of those services should be related to the amount, configuration and quality of the forest. However, in highly dynamic landscapes, such as some tropical regions, ecosystem services are potentially affected not only by the present landscape structure, but also by the historical land use. Here we propose a simple methodological framework to evaluate the contribution of past landscape dynamics and present landscape structure in the provision of ecosystem services. We applied this framework to a traditional agricultural landscape from the Brazilian Atlantic Forest hotspot, where natural forests cover has increased from 8 to 16 % in the last 60 years (1962–2008), and where old forests are being reduced while young forests are being regenerated. Forests of different ages, in association with current landscape structure, reveal a mosaic of forest patches under different conditions, implying different abilities to deliver ecosystem services. With the replacement of old-growth forests by young-regenerating forests and a high level of forest fragmentation, less than 1/4 of the current forest cover is able to fully satisfy the ecosystem service demands. To avoid such tendency, government policies should not only focus on increasing forest cover, but also in conserving old-growth forest fragments or increasing forest quality. The proposed methodology allows integrating historical land use and current landscape structure to evaluate ecosystem services provision and can be useful to establish programs of payment for ecosystem services.     

Influence of forest cover on in-stream large wood in an agricultural landscape of southeastern Brazil: a multi-scale analysis

Large wood (LW) is critical to the structure and function of streams and forests are the main LW source to stream channels. To assess the influence of forest cover changes at different spatial scales on in-stream LW quantity, we selected eighteen catchments (2nd–4th order) in Southeastern Brazil with forests at different levels of alterations. In each catchment we quantified the pattern of forest cover (% cover and relative catchment position), the physical characteristics of catchments (elevation and slope), the characteristics of channels (wetted channel width and depth), the abundance and volume of in-stream LW, and the frequency of LW pools. We used simple and multiple linear regression to assess the response of LW variables to landscape and stream reach variables. Most of the LW was relatively small; 72 % had a diameter <20 cm, and 66 % had a length <5 m. Although percent forest cover at reach scale had substantial support to explain LW variables, the best predictors of LW variables were forest cover at broader scales (LW abundance and LW pool frequency were best predicted by forest at intermediate distance at the catchment scale and LW volume was best predicted by forest cover at the drainage network scale), suggesting that downstream transport is an important process in addition to local processes in our study area. These findings have important management implications because although low forested reaches receive less LW from local forests (or no LW in the case of deforested stream reaches), they are receiving LW from upstream forested reaches. However, the material is generally small, unstable and likely to be easily flushed. This suggests that not only should riparian forest conservation encompass the full drainage network, but forests should also be allowed to regenerate to later successional stages to provide larger, higher quality LW for natural structuring of streams.     

Effect of Acute Administration of Clenbuterol on Athletic Performance in Horses

The aim of the study was to determine the effect of clenbuterol on the anaerobic threshold of horses on a treadmill with increasing physical stress, measuring heart rate (HR) and blood levels of lactate, glucose, and insulin. Twelve Arabian horses were submitted to two physical tests separated by a 10-day interval. Clenbuterol (CL) at 0.8 μg/kg or saline (control—C) was administered intravenously 30 minutes before the test. The treadmill exercise test consisted of an initial warmup followed by a gradually increasing effort. There was no statistical difference in either V₂ or V₄ (velocity at which plasma lactate concentration reached 4 and 2 mmol/L, respectively) between the two experimental groups. For the CL group, V₂₀₀, V₁₈₀, V₁₆₀, and V₁₄₀ (velocity at which the rate heart is 140, 160, 180, and 200 beats/minute, respectively) decreased significantly. At rest as well as times 4, 6, and 10 minutes, insulin levels were higher in the group that received clenbuterol (P < .05). Contrary to what was expected, apparently, there was no improvement in aerobic metabolism in animals when given a therapeutic dose of the bronchodilator. The elevated heart rate observed could have been attributable to the stimulation of cardiac β₁ adrenoceptors and the increased insulin levels to the stimulation of pancreatic β₂ receptors.