The Human Genomic Melting Map

In a living cell, the antiparallel double-stranded helix of DNA is a dynamically changing structure. The structure relates to interactions between and within the DNA strands, and the array of other macromolecules that constitutes functional chromatin. It is only through its changing conformations that DNA can organize and structure a large number of cellular functions. In particular, DNA must locally uncoil, or melt, and become single-stranded for DNA replication, repair, recombination, and transcription to occur. It has previously been shown that this melting occurs cooperatively, whereby several base pairs act in concert to generate melting bubbles, and in this way constitute a domain that behaves as a unit with respect to local DNA single-strandedness. We have applied a melting map calculation to the complete human genome, which provides information about the propensities of forming local bubbles determined from the whole sequence, and present a first report on its basic features, the extent of cooperativity, and correlations to various physical and biological features of the human genome. Globally, the melting map covaries very strongly with GC content. Most importantly, however, cooperativity of DNA denaturation causes this correlation to be weaker at resolutions fewer than 500 bps. This is also the resolution level at which most structural and biological processes occur, signifying the importance of the informational content inherent in the genomic melting map. The human DNA melting map may be further explored at http://meltmap.uio.no

Fresh air in the 21st century?

Ozone is an air quality problem today for much of the world's population. Regions can exceed the ozone air quality standards (AQS) through a combination of local emissions, meteorology favoring pollution episodes, and the clean-air baseline levels of ozone upon which pollution builds. The IPCC 2001 assessment studied a range of global emission scenarios and found that all but one projects increases in global tropospheric ozone during the 21st century. By 2030, near-surface increases over much of the northern hemisphere are estimated to be about 5 ppb (+2 to +7 ppb over the range of scenarios). By 2100 the two more extreme scenarios project baseline ozone increases of >20 ppb, while the other four scenarios give changes of -4 to +10 ppb. Even modest increases in the background abundance of tropospheric ozone might defeat current AQS strategies. The larger increases, however, would gravely threaten both urban and rural air quality over most of the northern hemisphere

International Research Infrastructure Landscape 2019 : A European Perspective

The report is the final product of the RISCAPE project, funded by the European Commission H2020 programme

International Research Infrastucture Landscape 2019: A European Perspective

The book 'International Research Infrastucture Landscape 2019: A European Perspective' provides the final report of the RISCAPE-project, supported by the European Commission's Horizon 2020-project. The RISCAPE-project aims to provide a systematic, focused, high-quality, comprehensive, consistent and peer-reviewed international landscape analysis report on the position and complementarities of the major European RIs in the international Research Infrastructure landscape.University of Turku has contributed with the domain report on international Energy Research Infrastructures, which forms chapter 6 of the final book.</p

A Study of Tropospheric Ozone over China with a 3-D Global CTM Model

A global 3-D CTM model (OsloCTM2) has been used to study the tropospheric ozone distribution and budget over China. An area covering China and most of East Asia is chosen as the study area. Because of the very nevenly distributed emissions and population in China, the budget study has been done by splitting China into three sub-areas, according to the emission distribution and topography of the country. The model results indicate that in Western China (Area1) dynamic processes are dominating, and the contribution from photochemical ozone production is small. Central and South-East China (Area2) has on average 65% of the photochemical ozone production in China, since more than 80% of the anthropogenic emissions come from this area. Northeast China (Area3) is influenced both by natural and*9nthropogenic emissions. The seasonal variation of ozone budgets was calculated in order to understand how different processes vary with the seasons. The strongest influences of emissions from the continent over the West Pacific region are found in spring, because of the large eastward transport and increased photochemical activities. Most NOx is consumed close to the emission sources; therefore, only 4% of emitted NOx is transported out of China, whereas 70% of the emitted CO is exported. It is calculated that the average net chemical ozone production efficiency by NOx loss is 7.2 in China

Correlations of Melting Temperature (Tm) with G + C Content

<p>The correlation coefficients between GC content and Tm are plotted as a function of window sizes. For each chromosome, excluding the segments which contain unknown bases (N's), the correlation coefficient was calculated from all pairs of GC content and average Tm over all nonoverlapping segments of a given window size. Across the chromosomes, the average correlation coefficients and SDs were calculated for each window size. The figure shows the average correlations with SDs (error bars) for window sizes from 10 bp to 1 Mbp for the human chromosomes (red) and the randomized chromosomes (blue).</p

Scatter Plot of Melting Temperature versus GC Content of Flat Melting Segments

<p>Using Chromosome 21, the relationship between local GC content and melting temperature was examined for all flat segments of 50 bps. <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.0030093#pcbi-0030093-g004" target="_blank">Figure 4</a> shows the scatter plot of melting temperature versus GC content. Each data point in this figure represents a 50-bp flat segment. The red dots represent those segments that have higher melting temperatures (Tm) in its neighboring regions at both sides (denoted as category I). The blue dots represent those that have lower Tm in its neighbors (denoted as category III). And, the green dots represent those that have lower Tm in one side neighbor and higher Tm in another (denoted as category II).</p