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PubMed
CTCF: the protein, the binding partners, the binding sites and their chromatin loops
Philos Trans R Soc Lond B Biol Sci
CTCF has it all. The transcription factor binds to tens of thousands of genomic sites, some tissue-specific, others ultra-conserved. It can act as a transcriptional activator, repressor and insulator, and it can pause transcription. CTCF binds at chr...
PubMed
Deciphering cis-regulatory control in inflammatory cells
Philos Trans R Soc Lond B Biol Sci
In innate immune system cells, such as macrophages and dendritic cells, deployment of inducible gene expression programmes in response to microbes and danger signals requires highly precise regulatory mechanisms. The inflammatory response has to be t...
PubMed
Regulation from a distance: long-range control of gene expression in development and disease
Philos Trans R Soc Lond B Biol Sci
PubMed
Bevacizumab for the Treatment of Glioblastoma
Clin Med Insights Oncol
Glioblastoma (GBM) or grade IV glioma is the most common primary brain tumor in adults. Standard treatment median overall survival (OS) is only 14–15 months and less than 10% of patients will survive 5 years after diagnosis. There is no standard tr...
PubMed
Evidence for the Presence of 1,3-Dimethylamylamine (1,3-DMAA) in Geranium Plant Materials
Anal Chem Insights
1,3-Dimethylamylamine (1,3-DMAA) is an aliphatic amine with stimulant properties that are reportedly found naturally only in geranium plants (Pelargonium graveolens). The presence of 1,3-DMAA in geranium plants was first reported in a paper published...
PubMed
Global trends and uncertainties in terrestrial denitrification and N(2)O emissions
Philos Trans R Soc Lond B Biol Sci
Soil nitrogen (N) budgets are used in a global, distributed flow-path model with 0.5° × 0.5° resolution, representing denitrification and N(2)O emissions from soils, groundwater and riparian zones for the period 1900–2000 and scenarios for the p...
PubMed
The cycling of organic nitrogen through the atmosphere
Philos Trans R Soc Lond B Biol Sci
Atmospheric organic nitrogen (ON) appears to be a ubiquitous but poorly understood component of the atmospheric nitrogen deposition flux. Here, we focus on the ON components that dominate deposition and do not consider reactive atmospheric gases cont...
PubMed
Consequences of human modification of the global nitrogen cycle
Philos Trans R Soc Lond B Biol Sci
The demand for more food is increasing fertilizer and land use, and the demand for more energy is increasing fossil fuel combustion, leading to enhanced losses of reactive nitrogen (N(r)) to the environment. Many thresholds for human and ecosystem he...
PubMed
Biological nitrogen fixation: rates, patterns and ecological controls in terrestrial ecosystems
Philos Trans R Soc Lond B Biol Sci
New techniques have identified a wide range of organisms with the capacity to carry out biological nitrogen fixation (BNF)—greatly expanding our appreciation of the diversity and ubiquity of N fixers—but our understanding of the rates and control...
PubMed
A chronology of human understanding of the nitrogen cycle(†)
Philos Trans R Soc Lond B Biol Sci
Nitrogen over the ages! It was discovered in the eighteenth century. The following century, its importance in agriculture was documented and the basic components of its cycle were elucidated. In the twentieth century, a process to provide an inexhaus...
PubMed
The marine nitrogen cycle: recent discoveries, uncertainties and the potential relevance of climate change
Philos Trans R Soc Lond B Biol Sci
The ocean's nitrogen cycle is driven by complex microbial transformations, including nitrogen fixation, assimilation, nitrification, anammox and denitrification. Dinitrogen is the most abundant form of nitrogen in sea water but only accessible b...
PubMed
Nitrous oxide emissions from soils: how well do we understand the processes and their controls?
Philos Trans R Soc Lond B Biol Sci
Although it is well established that soils are the dominating source for atmospheric nitrous oxide (N(2)O), we are still struggling to fully understand the complexity of the underlying microbial production and consumption processes and the links to b...
PubMed
The nitrogen cascade from agricultural soils to the sea: modelling nitrogen transfers at regional watershed and global scales
Philos Trans R Soc Lond B Biol Sci
The nitrogen cycle of pre-industrial ecosystems has long been remarkably closed, in spite of the high mobility of this element in the atmosphere and hydrosphere. Inter-regional and international commercial exchanges of agricultural goods, which consi...
PubMed
Sensitivity of continental United States atmospheric budgets of oxidized and reduced nitrogen to dry deposition parametrizations
Philos Trans R Soc Lond B Biol Sci
Reactive nitrogen (N(r)) is removed by surface fluxes (air–surface exchange) and wet deposition. The chemistry and physics of the atmosphere result in a complicated system in which competing chemical sources and sinks exist and impact that removal....
PubMed
Terrestrial nitrogen–carbon cycle interactions at the global scale
Philos Trans R Soc Lond B Biol Sci
Interactions between the terrestrial nitrogen (N) and carbon (C) cycles shape the response of ecosystems to global change. However, the global distribution of nitrogen availability and its importance in global biogeochemistry and biogeochemical inter...
PubMed
Processes regulating nitric oxide emissions from soils
Philos Trans R Soc Lond B Biol Sci
Nitric oxide (NO) is a reactive gas that plays an important role in atmospheric chemistry by influencing the production and destruction of ozone and thereby the oxidizing capacity of the atmosphere. NO also contributes by its oxidation products to th...
PubMed
Ice sheets and nitrogen
Philos Trans R Soc Lond B Biol Sci
Snow and ice play their most important role in the nitrogen cycle as a barrier to land–atmosphere and ocean–atmosphere exchanges that would otherwise occur. The inventory of nitrogen compounds in the polar ice sheets is approximately 260 Tg N, do...
PubMed
The global nitrogen cycle in the twenty-first century
Philos Trans R Soc Lond B Biol Sci
Global nitrogen fixation contributes 413 Tg of reactive nitrogen (N(r)) to terrestrial and marine ecosystems annually of which anthropogenic activities are responsible for half, 210 Tg N. The majority of the transformations of anthropogenic N(r) are ...
PubMed
The global nitrogen cycle in the twenty-first century: introduction
Philos Trans R Soc Lond B Biol Sci
PubMed
Towards a climate-dependent paradigm of ammonia emission and deposition
Philos Trans R Soc Lond B Biol Sci
Existing descriptions of bi-directional ammonia (NH(3)) land–atmosphere exchange incorporate temperature and moisture controls, and are beginning to be used in regional chemical transport models. However, such models have typically applied simpler ...