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61.
New Forests - Cut stumps are the legacy of forest harvesting and allow for the estimation of carbon loss from the ecosystem. The objective of this study was to estimate aboveground carbon storage...  相似文献   
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Three sorghum hybrids were tempered and decorticated with an abrasive‐type mill (scarifier) to produce low‐ash and low‐fat grits. The effects of tempering time and temperature were investigated, and the optimum tempering conditions for obtaining low‐ash and low‐fat grits were found for each sorghum hybrid. The conditions were 3 min at 30°C for bronze sorghum with heteroyellow endosperm, 40 min at 40°C for white sorghum with white endosperm, and 10 min at 20°C for red sorghum with white endosperm. The grits yields were low using the scarifier, hence, another abrasive‐type mill was investigated for improving grits yields. A modified experimental corn decorticator‐degerminator was used to dry‐mill the three sorghum hybrids tempered to the optimum conditions found with the scarifier. The yields were 45.3% grits with 0.23% ash and 0.18% fat for the bronze/heteroyellow hybrid, 49.1% grits with 0.22% ash and 0.36% fat for white/white hybrid, and 44.2% grits with 0.20% ash and 0.22% fat for red/white hybrid. This study showed that grits yields were higher and ash and fat contents were lower when sorghum was processed with the decorticator‐degerminator than with the scarifier under the same optimum conditioning.  相似文献   
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The growth of commercial aquaculture in Chile generated an income of $2.300 million USD in exports in 2005. Currently, 15 different species are cultivated commercially, of which seven are native; these had returns of 185 million USD. Among these native species is Galaxias maculatus (whitebait), which is endemic to Chile and figures significantly in Chilean fishing statistics. Since the 1990s, the School of Aquaculture of the Universidad Catolica de Temuco has been developing cultivation of this native species. This work presents the state of the art of the cultivation of this fish.  相似文献   
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ABSTRACT Fusarium graminearum causes Fusarium head blight (FHB) in small grains worldwide. Although primarily a pathogen of cereals, it also can infect noncereal crops such as potato and sugar beet in the United States. We used a real-time polymerase chain reaction (PCR) method based on intergenic sequences specific to the trichodiene synthase gene (Tri5) from F. graminearum. TaqMan probe and primers were designed and used to estimate DNA content of the pathogen (FgDNA) in the susceptible wheat cv. Grandin after inoculation with the 21 isolates of F. graminearum collected from potato, sugar beet, and wheat. The presence of nine mycotoxins was analyzed in the inoculated wheat heads by gas chromatography and mass spectrometry. All isolates contained the Tri5 gene and were virulent to cv. Grandin. Isolates of F. graminearum differed significantly in virulence (expressed as disease severity), FgDNA content, and mycotoxin accumulation. Potato isolates showed greater variability in producing different mycotoxins than sugar beet and wheat isolates. Correlation analysis showed a significant (P < 0.001) positive relationship between FgDNA content and FHB severity or deoxynivalenol (DON) production. Moreover, a significant (P < 0.001) positive correlation between FHB severity and DON content was observed. Our findings revealed that F. graminearum causing potato dry rot and sugar beet decay could be potential sources of inoculum for FHB epidemics in wheat. Real-time PCR assay provides sensitive and accurate quantification of F. graminearum in wheat and can be useful for monitoring the colonization of wheat grains by F. graminearum in controlled environments, and evaluating wheat germplasms for resistance to FHB.  相似文献   
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Tropical Animal Health and Production - The purpose of this study was to determine the in vitro fermentation and methane (CH4) production in the grass Brachiaria brizantha (B) alone or when mixed...  相似文献   
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Developmental instability hypothesis suggests that asymmetric variation can partially reflect the body's inability to buffer environmental and/or genetic perturbations. Fluctuating asymmetry (FA), that is random differences between the left and right sides of body features that are symmetric at the population level, can assess this approach. Another kind of asymmetry is directional asymmetry (DA) which appears when the left and right sides differ consistently from each other. Extreme selection for morphological traits, as appear in some companion rabbits selected for a paedomorphic (dwarf rabbits) or gerontomorphic (belier rabbits) appearance, may cause abnormal functional conditions, which in turn could be expressed as significative degrees of asymmetries. To study these phenomena, we analysed 62 mandibles of companion rabbits (20 beliers and 42 dwarfs) by means of geometric morphometric methods and quantified their size and shape asymmetric variation (both FA and DA) using 18 landmarks on the lateral side. FA was present in both types but in different degrees, being higher among dwarfs. It is considered that this type is subject to deeper changes than among beliers, and therefore, there is higher pressure on the phenotype. This observation could be assumed to be an adaptive response, coming out as FA. The presence of DA was significative and similar for two types. This likely indicates common masticatory lateralization, a pattern that has been detected in other domestic mammals. The methodological framework presented in this study can be valuable for future works focused on genetically and/or environmentally related form study in pets.  相似文献   
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Summary The tuber-to-tuber variability in storage behaviour of seed tubers from true potato seed was compared with that in clonal seed tubers after storage in the dark, in diffused light, or in diffused light with a single desprouting. The variability was estimated by calculating standard deviations of length, number and weight of sprouts, and tuber weight loss. After dark storage, the variability of these variables was greater in seed tubers from true potato seed than in clonal seed tubers. After storage in diffused light with a single desprouting, the variability of number, length and weight of sprouts of seed tubers from true seed was not statistically different from that observed in clonal seed tubers. All storage treatments resulted in a greater variability of tuber weight loss in seed tubers from true potato seed than in clonal tubers.  相似文献   
69.
Analysis of grape and wine anthocyanins by HPLC-MS   总被引:2,自引:0,他引:2  
The development and application of valuable analytical tools suitable for the varietal authentication of premium red wines are matters of interest in order to avoid fraud. In this study, an HPLC-MS procedure has been developed using trifluoroacetic acid as an acid modifier in the mobile phase. This method may be used as a routine method using UV-vis detection and allows the simultaneous analysis of the structural features of anthocyanins by MS under the same chromatographic conditions. Twenty different anthocyanins have been detected in 19 different samples of both grape extracts and wines. Cis and trans isomers of p-coumaryl derivatives have been identified for the first time. Important qualitative and quantitative differences among cultivars have been detected.  相似文献   
70.
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