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101.
The aim was to compare the effects of two production systems on performance, carcass traits and physical‐mechanical characteristics of leather from Beefalo‐Nellore steers and heifers and to determine if the response to the production system was similar for both genders. A total of 40 Beefalo‐Nellore cattle, 20 steers and 20 heifers, were evaluated. Animals were divided into two production systems: slaughtered at 15 (intensive system) or 26 (extensive system) months of age. In the intensive system, all animals received a ration containing 600 g/kg corn silage and 400 g/kg concentrate. In the extensive system, animals were kept on a pasture predominantly based on Brachiaria sp. and supplemented with 2 kg/day concentrate. In the intensive system, there was no difference in slaughter weight (470 kg body weight) between steers and heifers but steers in the extensive system had greater slaughter weight than heifers (463 and 428 kg body weight, respectively). Leather weight was higher for animals in the intensive than extensive system but there was no difference in leather weight once excess fat was removed. Leather quality from Beefalo‐Nellore cattle slaughtered at 15 or 26 months of age is similar although carcass yield is higher for cattle slaughtered at a younger age.  相似文献   
102.
The color features and the evolution of both the monomeric and the derived pigments of red wines aged in oak and cherry 225 L barriques have been investigated during a four months period. For cherry wood, the utilization of 1000 L casks was tested as well. The use of cherry casks resulted in a faster evolution of pigments with a rapid decline of monomeric anthocyanins and a quick augmentation formation of derived and polymeric compounds. At the end of the aging, wines stored in oak and cherry barriques lost, respectively, about 20% and 80% of the initial pigment amount, while in the 1000 L cherry casks, the same compounds diminished by about 60%. Ethyl-bridged adducts and vitisins were the main class of derivatives formed, representing up to 25% of the total pigment amount in the cherry aged samples. Color density augmented in both the oak and cherry wood aged samples, but the latter had the highest values of this parameter. Because of the highly oxidative behavior of the cherry barriques, the use of larger casks (e.g., 1000 L) is proposed in the case of prolonged aging times.  相似文献   
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The effects of chemical (acid-heating treatment) and enzymatic (microbial transglutaminase, TGase) modification (deamidation) of gluten proteins on their physicochemical and celiac disease-related properties were studied. Ammonia release, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and sample solubility analyses were employed to check the extent of gluten modification. Among different treatments achieved, the acid-heating treatment performed at 90 degrees C for 3 h induced gluten deamidation, paralleling an increase of gluten solubility without relevant proteolysis. Changes in the immunoreactivity of celiac IgA anti-gliadin antibodies (AGAs) to modified gluten proteins were detected by using a competitive indirect enzyme-linked immunosorbent assay method. Chemical deamidation by acid-heating treatment of gluten lowered IgA-AGA immunoreactivity. IgA-AGA immunoreactivity to gliadins was increased when they were submitted to TGase-catalyzed deamidation. The acid-heating treatment of gluten reduced its cytotoxic activity on human colon adenocarcinoma LoVo cell line. These results showed that chemical deamidation of gluten may be envisaged as a way to lower the potential risk for celiac people due to widespread use of gluten as a food additive.  相似文献   
106.
The soybean product MON 87701 × MON 89788 expresses both the cry1Ac gene derived from Bacillus thuringiensis and the cp4 epsps (5-enolpyruvylshikimate-3-phosphate synthase) gene derived from Agrobacterium sp. strain CP4. Each biotechnology-derived trait confers specific benefits of insect resistance and glyphosate tolerance, respectively. The purpose of this study was to compare the composition of seed and forage from this combined-trait product to those of conventional soybean grown in geographically and climatically distinct regions. Field trials were conducted in the United States during the 2007 growing season, in Argentina during the 2007-2008 growing season, and in the northern and southern soybean regions of Brazil during the 2007-2008 and 2008-2009 growing seasons. Results demonstrated that the compositional equivalence of MON 87701 × MON 89788 to the conventional soybean extended across all regions and growing seasons. Further evaluation of the data showed that natural variation (region and growing season) contributed more to compositional variability in soybean, particularly for such components as isoflavones, fatty acids, and vitamin E, than transgene insertion.  相似文献   
107.
The influence of concentration and water activity (a(w)) on the formation of 5-hydroxymethyl-2-furancarboxaldehyde (HMF) in thermally treated grape must was evaluated. Must was cryoconcentrated and then heated to study the pure effect of sugar concentration. Moreover, NaCl was added to the must to lower a(w), maintaining the same sugar concentration, with the purpose of evaluating the pure effect of a(w). Finally, the influence of minimal pH changes on the formation of HMF was evaluated by means of a model solution. The results showed that a(w) and sugar concentration are both determinant in the formation of HMF in grape must. Sugar concentration influences the reaction by supplying substrates; low a(w) enhances the formation of HMF by changing the equilibrium in the dehydration step of the reaction.  相似文献   
108.
Since pristine Atlantic Forest remnants are vanishing, and biological reserves are in short, conservation of biodiversity will largely depend on proper management of the anthropogenic matrix. Here, we test (1) the effectiveness of ecologically-managed tree monocultures in maintaining Araucaria Forest biodiversity, (2) how this effectiveness change among taxa, and (3) we discuss management principles that can be used by the forestry industry in order to contribute positively to biodiversity conservation. The study was conducted in the São Francisco de Paula National Forest, southern Brazil, an environmental mosaic composed mostly of patches of Araucaria Forest and ecologically-managed monocultures of Araucaria, Pinus and Eucalyptus. Using standardized sampling methods in these four main habitats, we have recorded the richness and species composition of small mammals, birds, leaf-litter frogs, butterflies, galling insects, spiders, opiliones, flatworms, woody plants, epiphytic angiosperms, epiphytic ferns, lichens, and fruit-body producing fungi. Overall, we recorded 506 species in Araucaria Forest, 181 (36%) of which were exclusive of this habitat while 325 (64%) could be found in at least one monoculture. Distribution patterns of species richness and number of records across taxonomic groups showed that a large biodiversity can be found inside ecologically-managed plantations of Araucaria, Pinus, and Eucalyptus. For all studied taxa, except for epiphytic angiosperms and fruit-body producing fungi, more than half of the Araucaria Forest species could be found living on monocultures. We discuss how the actual management practices of the forest industry can be improved to contribute positively to the conservation of the Atlantic Forest biodiversity.  相似文献   
109.
The ecological importance of marine algae is widely known but in shallow coastal areas the composition and structure of algal communities may be affected by different human activities. Recovery from different trampling disturbances of two competing morphological groups (i.e. macroalgae and algal turfs) and effects of macroalgal canopy removal on the dominant associated fauna were examined using controlled trampling experiments. Six months after trampling disturbance was removed, the two morphological groups closely resembled control (untrampled) conditions, both in terms of cover and canopy (%). In particular, macroalgal recovery seemed to be very rapid: the higher the impact on the system the more rapid the recovery rate. In the short-term, the removal of macroalgal fronds (i.e. canopy) caused evident changes in invertebrate and crypto-benthic fish densities although these indirect effects were species-specific. Erect macroalgae are very sensitive to disturbance and even relatively low intensities of human use may be non-sustainable for this shallow assemblage. The present findings suggest some interesting options for the management of Mediterranean rocky shallow areas. This is crucial for coastal areas that are intended to be maintained in natural condition for conservation purposes.  相似文献   
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