Enabling Biological Nitrogen Fixation for Cereal Crops in Fertilized Fields.

Agricultural productivity relies on synthetic nitrogen fertilizers, yet half of that reactive nitrogen is lost to the environment. There is an urgent need for alternative nitrogen solutions to reduce the water pollution, ozone depletion, atmospheric particulate formation, and global greenhouse gas emissions associated with synthetic nitrogen fertilizer use. One such solution is biological nitrogen fixation (BNF), a component of the complex natural nitrogen cycle.

Biological nitrogen fixation in maize: optimizing nitrogenase expression in a root-associated diazotroph.

Plants depend upon beneficial interactions between roots and root-associated microorganisms for growth promotion, disease suppression, and nutrient availability. This includes the ability of free-living diazotrophic bacteria to supply nitrogen, an ecological role that has been long underappreciated in modern agriculture for efficient crop production systems. Long-term ecological studies in legume-rhizobia interactions have shown that elevated nitrogen inputs can lead to the evolution of less cooperative nitrogen-fixing mutualists.

The prevalence of comorbidities among people living with HIV in Brent: a diverse London Borough.

Background HIV has changed from a rapidly deteriorating illness to a complex chronic disease, with increasing incidences of comorbidity, including cancer, and liver, lung and cardiovascular diseases. North West London has 6719 individuals living with the human immunodeficiency virus (HIV), 873 of whom reside in the London Borough of Brent. Traditionally, commissioning services have focused on HIV therapy alone without considering how comorbidity affects treatment outcome and total service costs.

Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster.

Natural populations of most organisms harbor substantial genetic variation for resistance to infection. The continued existence of such variation is unexpected under simple evolutionary models that either posit direct and continuous natural selection on the immune system or an evolved life history "balance" between immunity and other fitness traits in a constant environment. However, both local adaptation to heterogeneous environments and genotype-by-environment interactions can maintain genetic variation in a species.

Lethality in Drosophila melanogaster/Drosophila simulans species hybrids is not associated with substantial transcriptional misregulation.

The cross of Drosophila melanogaster females to Drosophila simulans males produces lethal F1 hybrid males. These lethal phenotypes can be suppressed by mutations in the D. melanogaster gene Hybrid male rescue (Hmr), demonstrating that Hmr has a major role in causing lethality in this hybridization.