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As the climate changes, farmers in developing countries seek to employ strategies to help them sustain food production. The objectives of this paper were to identify adaptation strategies in response to climate change and the determinants for their adoption, and to explore the impact of these strategies on food security. The analysis was based on a survey of 900 small-scale farmers in a semi-arid (Dodoma) and a semi-humid (Morogoro) region in Tanzania. Farmers in the semi-humid region tended to diversify their crops, i.e. added additional crop types. Given the more challenging environment in the semi-arid region, farmers there changed their portfolio of crops, i.e. substituted some crops or cultivars with others. Logistic regressions highlighted higher tolerance to risk, land ownership, education and experiences of farmers as drivers of adoption, while income diversification had a negative effect. The propensity score matching approach showed that adopters of climate-smart strategies are on-average more food-secure. These users showed a more diverse pattern of food consumption, greater protein intake and better economic access to food. Changing crop portfolios can help households to cope with climate-related shocks such as droughts and thus appears to be the best performing strategy, especially in terms of more stable food provisioning throughout the year.  相似文献   
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In this work, the presence of biogenic amines (BAs) was correlated with the type of wine grape culture (traditional or organic) and their concentration in the different stages of winemaking (must, alcoholic fermentation [AF] and malolactic fermentation [MLF]). The formation of BA occurred mainly during MLF in which the percentages for putrescine, cadaverine, phenylethylamine, histamine, and tyramine were 100%, 70%, 13%, 61%, and 44% for the wines produced with traditional grapes and 100%, 94%, 25%, 88%, and 13% for the wines produced with organic grapes, respectively. In general, these latter wines exhibited a lower concentration of total amines. The principal component analysis and partial least-square discriminate analysis indicated that the generation of BA has a certain behavioral pattern in the wines analyzed, which is associated with the different stages of wine production and with the type of culture (traditional or organic) used in the wine grapes. Practical Application: Chemometrics tools can be useful as a method of characterization and classification in a global overview of the process variables involved in the development of toxic chemicals in foods, such as the production of BA in wine.  相似文献   
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The seed lipids of three species ofEntandraphragma (Meliaceae) contain the largest proportion (31–50%) ofcis-vaccenic acid ever found in nature. The acid is not indicative of the family as a whole and is found as a major fatty acid in the seed of only one additional species, besidesEntandraphragma, out of the 30 analyzed from this family. With the total oil comprising between 45 and 62% ofEntandraphragma seed, these species should be considered as a source of undecadioic acid for the production of nylon 11.  相似文献   
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The effects of fat, type of natural cheese, and adjunct process cheese ingredients were evaluated to determine factors that contribute to the botulinal safety of reduced-fat (RF) process cheese products stored at 30 degrees C. In the first set of experiments, pasteurized process cheese products (PPCPs) were formulated using full-fat (FF) Cheddar, 30% RF Cheddar, or skim milk (SM) cheese as cheese-base types and were standardized to 59% moisture, pH 5.75, 2.8 or 3.2% total salts, and 15 to 19% fat. Subsequent trials evaluated the effect of fat levels and adjunct ingredients in PPCPs made with SM, RF, and FF cheese (final fat levels, less than 1, 13, and 24%, respectively). When fat levels of PPCPs were comparable (15.1, 19.1, and 16.2 for product manufactured with SC, RE and FF cheese, respectively), botulinal toxin production was delayed for up to 2 days in PPCPs formulated with SM compared with RF or FF cheese; however, the effect was not statistically significant. When fat levels were reduced to less than 1% in SM PPCPs, toxin production was delayed 2 weeks in products made with SM compared with RF or FF cheese manufactured with 13 or 24% fat, respectively. The antibotulinal effect of adjunct ingredients varied among the products manufactured with different fat levels. Sodium lactate significantly delayed toxin production (P < 0.05) for all fat levels tested, whereas beta-glucan fat replacer did not delay toxin production. An enzyme-modified cheese used as a flavor enhancer significantly delayed toxin production (P < 0.05) in SM (less than 1% fat) products but had little to no inhibitory effect in RF (13% fat) and FF (24% fat) cheese products. Similarly, monolaurin increased the time to detectable toxin in SM products but was ineffective in RF or FF cheese products. These results verify that RF PPCPs exhibit greater safety than FF products and that safety may be enhanced by using certain adjunct ingredients as antimicrobials.  相似文献   
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W.B. Yeats' restoration and recreation of Ballylee Castle in the west of Ireland from 1916 as ‘Thoor Ballylee’ saw it become the symbol and metaphor of his work as a poet. With the help of the architect, William Scott, an exponent of the English Arts and Crafts school, Yeats placed the tower and its landscape at the centre of his vision of the Irish past. The Arts and Crafts aesthetic that underpinned Yeats' idealisation of Irish society opposed and decried the modernisation of rural Ireland, attempting to preserve it as an idyll for the urban intelligentsia. In his appropriation and reconstruction of Ballylee Castle Yeats sought both to locate himself amongst the peasantry of the west of Ireland whom he idealised in his work and to reassert his own roots amongst the dying colonial order. This paper explores the ambivalence of Yeats' cultural nationalism against the backdrop of republican violence and the emergence of the Free State.  相似文献   
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A mutant Bacillus stearothermophilus lactate dehydrogenase hasbeen prepared in which all three tryptophan residues in thewild-type enzyme have been replaced by tyrosines. In addition,a tyrosine residue has been mutated to a tryptophan, which actsas a fluorescence probe to monitor protein folding. The mutantenzyme crystallizes in the same crystal form as the wild-type.The crystal structure of the mutant has been determined at 2.8Å resolution. Solution studies have suggested that thereis little effect upon the mutant enzyme as judged by its kineticproperties. Comparison of the crystal structures of the mutantand wild-type enzymes confirms this conclusion, and revealsthat alterations in structure in the region of these mutationsare of a similar magnitude to those observed throughout thestructure, and are not significant when compared with the errorsin atomic positions expected for a structure at this resolution.  相似文献   
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