Una herencia en Manaos (anotaciones sobre historia ambiental, ecología política y agroecología en una perspectiva latinoamericana)

Este artículo pretende explorar algunas vinculaciones de la agroecología con la historia ambiental, en sus escalas macro y micro, y con la ecología política. Una clave de interpretación es un interrogante sobre la identidad latinoamericana, que es percibida como articulación y sedimentación de varias herencias diferentes,en la cultura, la tecnología, los paisajes y la naturaleza

Identification of a BRCA2-Specific modifier locus at 6p24 related to breast cancer risk

Common genetic variants contribute to the observed variation in breast cancer risk for BRCA2 mutation carriers; those known to date have all been found through population-based genome-wide association studies (GWAS). To comprehensively identify breast cancer risk modifying loci for BRCA2 mutation carriers, we conducted a deep replication of an ongoing GWAS discovery study. Using the ranked P-values of the breast cancer associations with the imputed genotype of 1.4 M SNPs, 19,029 SNPs were selected and designed for inclusion on a custom Illumina array that included a total of 211,155 SNPs as part of a multi-consortial project. DNA samples from 3,881 breast cancer affected and 4,330 unaffected BRCA2 mutation carriers from 47 studies belonging to the Consortium of Investigators of Modifiers of BRCA1/2 were genotyped and available for analysis. We replicated previously reported breast cancer susceptibility alleles in these BRCA2 mutation carriers and for several regions (including FGFR2, MAP3K1, CDKN2A/B, and PTHLH) identified SNPs that have stronger evidence of association than those previously published. We also identified a novel susceptibility allele at 6p24 that was inversely associated with risk in BRCA2 mutation carriers (rs9348512; per allele HR = 0.85, 95% CI 0.80-0.90, P = 3.9×10−8). This SNP was not associated with breast cancer risk either in the general population or in BRCA1 mutation carriers. The locus lies within a region containing TFAP2A, which encodes a transcriptional activation protein that interacts with several tumor suppressor genes. This report identifies the first breast cancer risk locus specific to a BRCA2 mutation background. This comprehensive update of novel and previously reported breast cancer susceptibility loci contributes to the establishment of a panel of SNPs that modify breast cancer risk in BRCA2 mutation carriers. This panel may have clinical utility for women with BRCA2 mutations weighing options for medical prevention of breast cancer

The Pastoral Economy and Environmental Degradation in Highl and Central Mexico, 1530-1600.

It is proposed that overstocking and overgrazing by sheep during the period 1560-90 caused environmental degradation evident by the end of the 16th century in the Valle del Mezquital. Data pertaining to demographic changes, l and use, l and tenure and the environment (soil, vegetation, climate, and water resources) were collected in the course of archival research. This information formed the basis for the presentation and discussion of three major processes: decline of the Indian population by 90%, 1521-1600; conversion of l and use to pastoralism with associated changes in l and tenure, 1530-1600; and environmental deterioration, 1550-1600. The demographic decline of the Indian communities facilitated the transference of l and to the Spanish system of l and use and l and tenure, and by 1600 66% of the total l and surface of the region had been converted to pastoralism. In the 1560s and 1570s Indian communities were displaced by the pressure of high densities of sheep, conversion of l and use therefore occurred in advance of the change in l and tenure. The density of animals declined during the 1580s and 1590s, but the conversion of l and to pastoralism continued until some communities were left with less than the legal area of common l and s. Environmental deterioration was clearly associated with overgrazing, and areas which had been intensively exploited exhibited erosion by the last decade of the century. By 1600 the carrying capacity of the region was half that reported for the 1560s and 70s and extensive pastoralism had replaced intensive pastoralism. The catchment value had also deteriorated and intensive agriculture was being ab and oned. Developing forms of social organization changed during the last quarter of the 16th century from intensively worked small holdings (for sheep raising and agriculture) to extensive pastoralism and large holdings. The study elucidates processes involved in the growth of colonial, rural socio-economic structures during the era prior to the formation of the great estates. The move to acquire large holdings after the late 1580s is seen as a response to the reduction in carrying capacity, and an effort to maintain stock numbers and production levels, in a situation of increased dem and for pastoral products.Ph.D.Latin American historyUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/159787/1/8402332.pd