<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mirza, Babur S</style></author><author><style face="normal" font="default" size="100%">Potisap, Chotima</style></author><author><style face="normal" font="default" size="100%">Nüsslein, Klaus</style></author><author><style face="normal" font="default" size="100%">Bohannan, Brendan J M</style></author><author><style face="normal" font="default" size="100%">Rodrigues, Jorge L M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Response of free-living nitrogen-fixing microorganisms to land use change in the Amazon rainforest.</style></title><secondary-title><style face="normal" font="default" size="100%">Appl Environ Microbiol</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Environ. Microbiol.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Agriculture</style></keyword><keyword><style  face="normal" font="default" size="100%">Bacteria</style></keyword><keyword><style  face="normal" font="default" size="100%">Biota</style></keyword><keyword><style  face="normal" font="default" size="100%">Carbon</style></keyword><keyword><style  face="normal" font="default" size="100%">Cluster Analysis</style></keyword><keyword><style  face="normal" font="default" size="100%">Conservation of Natural Resources</style></keyword><keyword><style  face="normal" font="default" size="100%">Human Activities</style></keyword><keyword><style  face="normal" font="default" size="100%">Hydrogen-Ion Concentration</style></keyword><keyword><style  face="normal" font="default" size="100%">Molecular Sequence Data</style></keyword><keyword><style  face="normal" font="default" size="100%">Nitrogen</style></keyword><keyword><style  face="normal" font="default" size="100%">Nitrogen Fixation</style></keyword><keyword><style  face="normal" font="default" size="100%">Oxidoreductases</style></keyword><keyword><style  face="normal" font="default" size="100%">Phylogeny</style></keyword><keyword><style  face="normal" font="default" size="100%">Sequence Analysis, DNA</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil Microbiology</style></keyword><keyword><style  face="normal" font="default" size="100%">South America</style></keyword><keyword><style  face="normal" font="default" size="100%">Trees</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2014</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2014 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">80</style></volume><pages><style face="normal" font="default" size="100%">281-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The Amazon rainforest, the largest equatorial forest in the world, is being cleared for pasture and agricultural use at alarming rates. Tropical deforestation is known to cause alterations in microbial communities at taxonomic and phylogenetic levels, but it is unclear whether microbial functional groups are altered. We asked whether free-living nitrogen-fixing microorganisms (diazotrophs) respond to deforestation in the Amazon rainforest, using analysis of the marker gene nifH. Clone libraries were generated from soil samples collected from a primary forest, a 5-year-old pasture originally converted from primary forest, and a secondary forest established after pasture abandonment. Although diazotroph richness did not significantly change among the three plots, diazotroph community composition was altered with forest-to-pasture conversion, and phylogenetic similarity was higher among pasture communities than among those in forests. There was also 10-fold increase in nifH gene abundance following conversion from primary forest to pasture. Three environmental factors were associated with the observed changes: soil acidity, total N concentration, and C/N ratio. Our results suggest a partial restoration to initial levels of abundance and community structure of diazotrophs following pasture abandonment, with primary and secondary forests sharing similar communities. We postulate that the response of diazotrophs to land use change is a direct consequence of changes in plant communities, particularly the higher N demand of pasture plant communities for supporting aboveground plant growth.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rich, S M</style></author><author><style face="normal" font="default" size="100%">Licht, M C</style></author><author><style face="normal" font="default" size="100%">Hudson, R R</style></author><author><style face="normal" font="default" size="100%">Ayala, F J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Malaria's Eve: evidence of a recent population bottleneck throughout the world populations of Plasmodium falciparum.</style></title><secondary-title><style face="normal" font="default" size="100%">Proc Natl Acad Sci U S A</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Africa</style></keyword><keyword><style  face="normal" font="default" size="100%">Animals</style></keyword><keyword><style  face="normal" font="default" size="100%">Asia</style></keyword><keyword><style  face="normal" font="default" size="100%">Climate</style></keyword><keyword><style  face="normal" font="default" size="100%">Demography</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA, Protozoan</style></keyword><keyword><style  face="normal" font="default" size="100%">Evolution, Molecular</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Protozoan</style></keyword><keyword><style  face="normal" font="default" size="100%">Humans</style></keyword><keyword><style  face="normal" font="default" size="100%">Life Cycle Stages</style></keyword><keyword><style  face="normal" font="default" size="100%">Malaria</style></keyword><keyword><style  face="normal" font="default" size="100%">Malaria, Falciparum</style></keyword><keyword><style  face="normal" font="default" size="100%">Netherlands</style></keyword><keyword><style  face="normal" font="default" size="100%">Phylogeny</style></keyword><keyword><style  face="normal" font="default" size="100%">Plasmodium</style></keyword><keyword><style  face="normal" font="default" size="100%">Plasmodium falciparum</style></keyword><keyword><style  face="normal" font="default" size="100%">Polymorphism, Genetic</style></keyword><keyword><style  face="normal" font="default" size="100%">South America</style></keyword><keyword><style  face="normal" font="default" size="100%">Tetrahydrofolate Dehydrogenase</style></keyword><keyword><style  face="normal" font="default" size="100%">Time</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1998</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1998 Apr 14</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">95</style></volume><pages><style face="normal" font="default" size="100%">4425-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We have analyzed DNA sequences from world-wide geographic strains of Plasmodium falciparum and found a complete absence of synonymous DNA polymorphism at 10 gene loci. We hypothesize that all extant world populations of the parasite have recently derived (within several thousand years) from a single ancestral strain. The upper limit of the 95% confidence interval for the time when this most recent common ancestor lived is between 24,500 and 57,500 years ago (depending on different estimates of the nucleotide substitution rate); the actual time is likely to be much more recent. The recent origin of the P. falciparum populations could have resulted from either a demographic sweep (P. falciparum has only recently spread throughout the world from a small geographically confined population) or a selective sweep (one strain favored by natural selection has recently replaced all others). The selective sweep hypothesis requires that populations of P. falciparum be effectively clonal, despite the obligate sexual stage of the parasite life cycle. A demographic sweep that started several thousand years ago is consistent with worldwide climatic changes ensuing the last glaciation, increased anthropophilia of the mosquito vectors, and the spread of agriculture. P. falciparum may have rapidly spread from its African tropical origins to the tropical and subtropical regions of the world only within the last 6,000 years. The recent origin of the world-wide P. falciparum populations may account for its virulence, as the most malignant of human malarial parasites.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/9539753?dopt=Abstract</style></custom1></record></records></xml>