8,360 research outputs found

    Origin and genetic diversity of diploid parthenogenetic Artemia in Eurasia

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    There is wide interest in understanding how genetic diversity is generated and maintained in parthenogenetic lineages, as it will help clarify the debate of the evolution and maintenance of sexual reproduction. There are three mechanisms that can be responsible for the generation of genetic diversity of parthenogenetic lineages: contagious parthenogenesis, repeated hybridization and microorganism infections (e.g. Wolbachia). Brine shrimps of the genus Artemia (Crustacea, Branchiopoda, Anostraca) are a good model system to investigate evolutionary transitions between reproductive systems as they include sexual species and lineages of obligate parthenogenetic populations of different ploidy level, which often co-occur. Diploid parthenogenetic lineages produce occasional fully functional rare males, interspecific hybridization is known to occur, but the mechanisms of origin of asexual lineages are not completely understood. Here we sequenced and analysed fragments of one mitochondrial and two nuclear genes from an extensive set of populations of diploid parthenogenetic Artemia and sexual species from Central and East Asia to investigate the evolutionary origin of diploid parthenogenetic Artemia, and geographic origin of the parental taxa. Our results indicate that there are at least two, possibly three independent and recent maternal origins of parthenogenetic lineages, related to A. urmiana and Artemia sp. from Kazakhstan, but that the nuclear genes are very closely related in all the sexual species and parthenogegetic lineages except for A. sinica, who presumable took no part on the origin of diploid parthenogenetic strains. Our data cannot rule out either hybridization between any of the very closely related Asiatic sexual species or rare events of contagious parthenogenesis via rare males as the contributing mechanisms to the generation of genetic diversity in diploid parthenogenetic Artemia lineages

    Inequality of Outcomes and Inequality of Opportunities in Brazil

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    This paper departs from John Roemer's theory of equality of opportunities. We seek to determine what part of observed outcome inequality may be attributed to differences in observed 'circumstances', including family background, and what part is due to 'personal efforts'. We use a micro-econometric technique to simulate what the distribution of outcomes would look like if 'circumstances' were the same for everybody. This technique is applied to Brazilian data from the 1996 household survey, both for earnings and for household incomes. It is shown that observed circumstances are a major source of outcome inequality in Brazil, probably more so than in other countries for which information is available. Nevertheless, the level of inequality after observed circumstances are equalized remains very high in Brazil.http://deepblue.lib.umich.edu/bitstream/2027.42/40016/3/wp630.pd

    Correction:Carbonyl trapping and antiglycative activities of olive oil mill wastewater

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    Correction for ‘Carbonyl trapping and antiglycative activities of olive oil mill wastewater’ by Marta Navarro et al., Food Funct., 2015, 6, 574–583

    Inequality of Outcomes and Inequality of Opportunities in Brazil

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    This paper departs from John Roemer's theory of equality of opportunities. We seek to determine what part of observed outcome inequality may be attributed to differences in observed 'circumstances', including family background, and what part is due to 'personal efforts'. We use a micro-econometric technique to simulate what the distribution of outcomes would look like if 'circumstances' were the same for everybody. This technique is applied to Brazilian data from the 1996 household survey, both for earnings and for household incomes. It is shown that observed circumstances are a major source of outcome inequality in Brazil, probably more so than in other countries for which information is available. Nevertheless, the level of inequality after observed circumstances are equalized remains very high in Brazil.Inequality of Opportunities, Intergenerational Educational Mobility

    Inequality of outcomes and inequality of opportunities in Brazil

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    This paper departs from John Roemer's formulation of the theory of equality of opportunities. It seeks to determine what part of observed outcome inequality may be attributed to differences in observed 'circumstances', including family background, and what part is due to 'personal efforts'. We use a micro-econometric technique to simulate what the distribution of outcomes would look like if 'circumstances' were the same for everybody. This technique is applied to Brazilian data from the 1996 household survey, both on the distribution of earnings for active individuals and on the distribution of household income per capita. It is shown that observed circumstances are a major source of outcome inequality in Brazil, probably more so than in other countries for which information is available. Yet, the level of inequality after equalizing circumstances remains very high. While a policy aimed at equalizing opportunities - through facilitating more equal access to schooling, for instance - might therefore be successful in lowering Brazilian inequality somewhat, more ambitious targets for inequality reduction may require more direct income redistribution.Inequality of Opportunities, Intergenerational Educational Mobility JEL Codes: D31, D63, J62

    Inequality of outcomes and inequality of opportunities in Brazil

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    The authors depart from John Roemer's theory of equality of opportunities. They seek to determine what part of observed outcome inequality may be attributed to differences in observed"circumstances,"including family background, and what part is due to"personal efforts."The authors use a microeconometric technique to simulate what the distribution of outcomes would look like if circumstances were the same for everybody. They apply this technique to Brazilian data from the 1996 household survey, both for earnings and for household incomes. The authors show that observed circumstances are a major source of outcome inequality in Brazil, probably more so than in other countries for which information is available. Nevertheless, the level of inequality after observed circumstances are equalized remains very high in Brazil.Economic Theory&Research,Public Health Promotion,Curriculum&Instruction,Teaching and Learning,Health Monitoring&Evaluation,Health Monitoring&Evaluation,Teaching and Learning,Economic Theory&Research,Inequality,Poverty Impact Evaluation

    Explorative investigation of the anti-glycative effect of a rapeseed by-product extract

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    Formation of Advanced Glycation End-products (AGEs) in biological systems are increased during hyperglycaemia due to higher levels of circulating glucose, as well as carbonyl reactive species. AGEs are causative factors of common chronic diseases. Since synthetic AGE-inhibitors exert unwanted side effects and polyphenols act as potent antiglycative agents, vegetables (fruits, seeds and related by-products) are good candidates for searching natural inhibitors. The aim of this research is to explore the suitability of a polyphenol-rich rapeseed cake extract (RCext) to decrease the formation of AGEs in an in vitro model. Total Phenolic Content, antioxidant, anti-glycative activity, specific inhibition of AGEs (pentosidine and argypyrimidine), and methylglyoxal trapping capacity of the RCext were evaluated. The metabolomic profile of the extract was also analysed through GC-MS. Different phenols, amino acids, carbohydrates, organic acids and fatty acids are identified in the RCE by GC-MS. Results confirm the high concentration of polyphenols correlated with the antioxidant capacity and anti-glycative activity in a dose dependent manner. Rapeseed cake extract (3.7 mg mL−1) significantly reduced the formation of free fluorescent AGEs and pentosidine up to 34.85%. The anti-glycative activity of the extract is likely to be due to the high concentration of sinapinic acid in its metabolic profile, and the mechanism of action is mediated by methylglyoxal trapping. Results show a promising potential for using rapeseed cake extract as a food supplement to ameliorate the formation of AGEs. Rapeseed cake extract should therefore be considered a potential candidate for the prevention of glycation-associated complications of age-related pathologie
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