While South Americans are underrepresented in human genomic diversity studies, Brazil has been a classical model for population genetics studies on admixture. We present the results of the EPIGEN Brazil Initiative, the most comprehensive up-to-date genomic analysis of any Latin-American population. A population-based genomewide analysis of 6,487 individuals was performed in the context of worldwide genomic diversity to elucidate how ancestry, kinship, and inbreeding interact in three populations with different histories from the Northeast (African ancestry: 50%), Southeast, and South (both with European ancestry >70%) of Brazil. We showed that ancestry-positive assortative mating permeated Brazilian history. We traced European ancestry in the Southeast/South to a wider European/Middle Eastern region with respect to the Northeast, where ancestry seems restricted to Iberia. By developing an approximate Bayesian computation framework, we infer more recent European immigration to the Southeast/South than to the Northeast. Also, the observed low Native-American ancestry (6-8%) was mostly introduced in different regions of Brazil soon after the European Conquest. We broadened our understanding of the African diaspora, the major destination of which was Brazil, by revealing that Brazilians display two within-Africa ancestry components: one associated with non-Bantu/western Africans (more evident in the Northeast and African Americans) and one associated with Bantu/eastern Africans (more present in the Southeast/ South). Furthermore, the whole-genome analysis of 30 individuals (42-fold deep coverage) shows that continental admixture rather than local post-Columbian history is the main and complex determinant of the individual amount of deleterious genotypes.Latin America | population genetics | Salvador SCAALA | Bambuí Cohort Study of Ageing | Pelotas Birth Cohort Study L atin Americans, who are classical models of the effects of admixture in human populations (1, 2), remain underrepresented in studies of human genomic diversity, notwithstanding recent studies (3, 4). Indeed, no large genome-wide study on admixed South Americans has been conducted so far. Brazil is the largest and most populous Latin-American country. Its over 200 million inhabitants are the product of post-Columbian admixture between Amerindians, Europeans colonizers or immigrants, and African slaves (1). Interestingly, Brazil was the destiny of nearly 40% of the African diaspora, receiving seven times more slaves than the United States (nearly 4 million vs. 600,000).Here, we present results of the EPIGEN Brazil Initiative (https:// epigen.grude.ufmg.br), the most comprehensive up-to-date genomic analysis of a Latin-American population. We genotyped nearly 2.2 million SNPs in 6,487 admixed individuals from three population-based cohorts from different regions with distinct demographic and socioeconomic backgrounds and sequenced the whole genome of 30 individuals from these populations at an To whom correspondence should be addressed. Email: edutars@ic...

The surface and interface enthalpies of cubic stabilized zirconia solid solutions containing 8, 10, and 12 mol % Y 2 O 3 were determined by a combination of calorimetric, morphological, and structural analyses techniques. Nanocrystalline samples with several surface areas and degrees of agglomeration were synthesized by simultaneous precipitation and annealing at temperatures of 470-900 °C. Samples were characterized by X-ray diffraction and Raman spectroscopy. Surface areas were measured by N 2 adsorption, and interface areas were estimated by comparing surface areas from N 2 adsorption to those derived from an analysis of the crystallite sizes refined from X-ray diffraction data. Calorimetric measurements of heat of solution in a sodium molybdate melt, as a function of surface and interface areas, enabled us to experimentally derive trends in the surface and interface enthalpies of hydroxylated surfaces. Accounting for heats of water adsorption measured by microcalorimetry allowed us to obtain the surface enthalpies (energies) of the anhydrous surfaces at each composition. Average surface enthalpies were determined to increase with yttria content, from 0.85 ( 0.07 J/m 2 (for 8 mol % yttria) to 1.27 ( 0.08 J/m 2 (for 12 mol % yttria) for the hydrous surface and from 1.16 ( 0.08 J/m 2 to 1.80 ( 0.10 J/m 2 for the anhydrous surface. Interface enthalpies were determined to be in the range of 0.9 ( 0.5 J/m 2 for all studied compositions. Comparisons with measured surface energies for pure ZrO 2 , and Y 2 O 3 nanopowders and grain-boundary energies for YSZ dense nanoceramics are presented.

Barium hollandites, a family of framework titanates that can potentially be used for the immobilization of short‐lived fission products (especially 137Cs) in radioactive wastes, have been investigated by high‐temperature oxide melt solution calorimetry using 2PbO·B2O3 solvent at 702°C. The enthalpies of formation from constituent oxides show increasing energetic stability of the hollandite phase as Ti4+ is substituted by Mg2+, Al3+, and Fe3+, in that order. In general, the thermodynamic stability increases with decreasing average cation radius in the β sites, and when the tolerance factor approaches one. The Al‐ and Fe‐hollandites are more stable than phase assemblages containing BaTiO3 perovskite and Al/Fe/Ti oxides, whereas Mg‐hollandite is less stable than the corresponding assemblage of BaTiO3 perovskite, MgTiO3 ilmenite, and TiO2. This instability makes Mg‐hollandite a less suitable host for fission products. Hollandite phase formation during metal citrate combustion synthesis depends more on thermodynamic stability and phase chemistry than on the annealing temperature.

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