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Uppsala, Sweden

Uppsala University is a research university in Uppsala, Sweden, and is the oldest university in Sweden, founded in 1477. It ranks among the best universities in Northern Europe and in international rankings.The university rose to pronounced significance during the rise of Sweden as a great power at the end of the 16th century and was then given a relative financial stability with the large donation of King Gustavus Adolphus in the early 17th century. Uppsala also has an important historical place in Swedish national culture, identity and for the Swedish establishment: in historiography, literature, politics, and music. Many aspects of Swedish academic culture in general, such as the white student cap, originated in Uppsala. It shares some peculiarities, such as the student nation system, with Lund University and the University of Helsinki.Uppsala belongs to the Coimbra Group of European universities. The university has nine faculties distributed over three “disciplinary domains”. It has about 24,000 full-time students and 2,400 doctoral students. It has a teaching staff of roughly 1,800 out of a total of 6,500 employees. Twenty-five per cent of the 674 professors at the university are women. Of its turnover of SEK 5.9 billion in 2013, 30% was spent on education on basic and advanced level, while 66% was spent on research and research programs.Architecturally, Uppsala University has traditionally had a strong presence in the area around the cathedral on the western side of the River Fyris. Despite some more contemporary building developments further away from the centre, Uppsala's historic centre continues to be dominated by the presence of the university. Wikipedia.

There has been extensive traffic of male-biased genes out of the mammalian and Drosophila X-chromosomes, and there are also reports of an under-representation of male-biased genes on the X. This may reflect an adaptive process driven by natural selection where an autosomal location of male-biased genes is favored since male genes are only exposed to selection one-third of the time when X-linked. However, there are several alternative explanations to "out-of-the-X" gene movement, including mutational bias and a means for X-linked genes to escape meiotic sex chromosome inactivation (MSCI) during spermatogenesis. As a critical test of the hypothesis that genomic relocation of sex-biased genes is an adaptive process, I examined the emergence, and loss, of genes on the chicken Z-chromosome, i.e., a female heterogametic system (males ZZ, females ZW). Here, the analogous prediction would be an emergence of male-biased genes onto, not a loss from, the Z-chromosome because Z is foundmore often in males than autosomes are. I found that genes expressed in testis but not in ovary are highly over-represented among genes that have emerged on the Z-chromosome during avian evolution. Moreover, genes with male-biased expression are similarly over-represented among new Z-chromosomal genes. Interestingly, genes with female-biased expression have more often moved from than to the Z-chromosome. These observations show that male and female heterogametic organisms display opposing directionalities in the emergence and loss of sex-biased genes on sex chromosomes. This is consistent with theoretical models on the evolution of sexually antagonistic genes in which new mutations are at least partly dominant. © 2011 by Cold Spring Harbor Laboratory Press. Source

We investigate the effect of edges on the intrinsic d-wave superconducting state in graphene doped close to the van Hove singularity. While the bulk is in a chiral d x2-y2+id xy state, the order parameter at any edge is enhanced and has d x2-y2-symmetry, with a decay length strongly increasing with weakening superconductivity. No graphene edge is pair breaking for the d x2-y2 state, and there are no localized zero-energy edge states. We find two chiral edge modes which carry a spontaneous, but not quantized, quasiparticle current related to the zero-energy momentum. Moreover, for realistic values of the Rashba spin-orbit coupling, a Majorana fermion appears at the edge when tuning a Zeeman field. © 2012 American Physical Society. Source

Ellegren H.,Uppsala University
Annual Review of Ecology, Evolution, and Systematics

Rapidly accumulating genome sequence information in birds, which show several unique genomic features, provides novel insights into evolutionary genomics. The avian karyotype with numerous microchromosomes has remained stable during evolution, although frequent intrachromosomal inversions have occurred. Avian sex chromosome evolution, representing the best characterized ZW system to date, follows patterns seen in other organisms but has the notable exception of incomplete dosage compensation. Recombination is unevenly distributed in the avian genome; it occurs at very high rates in microchromosomes, a consequence of an obligate crossing over in even small chromosomes, and has highly elevated rates near chromosome ends. Moreover, a heterogeneous landscape of recombination feeds significant heterogeneity in base composition via GC-biased gene conversion. A uniform molecular clock is not applicable to birds, and ample evidence for substitution rate heterogeneity both among lineages and within genomes exists. Observed genome-wide levels of nucleotide diversity in birds are in the range of 10-2-10-3. © Copyright ©2013 by Annual Reviews. All rights reserved. Source

Heldin C.-H.,Uppsala University
Cell Communication and Signaling

Platelet-derived growth factor (PDGF) isoforms and PDGF receptors have important functions in the regulation of growth and survival of certain cell types during embryonal development and e.g. tissue repair in the adult. Overactivity of PDGF receptor signaling, by overexpression or mutational events, may drive tumor cell growth. In addition, pericytes of the vasculature and fibroblasts and myofibroblasts of the stroma of solid tumors express PDGF receptors, and PDGF stimulation of such cells promotes tumorigenesis. Inhibition of PDGF receptor signaling has proven to useful for the treatment of patients with certain rare tumors. Whether treatment with PDGF/PDGF receptor antagonists will be beneficial for more common malignancies is the subject for ongoing studies. © 2013 Heldin; licensee BioMed Central Ltd. Source

Ellegren H.,Uppsala University
Trends in Ecology and Evolution

High-throughput sequencing technologies are revolutionizing the life sciences. The past 12 months have seen a burst of genome sequences from non-model organisms, in each case representing a fundamental source of data of significant importance to biological research. This has bearing on several aspects of evolutionary biology, and we are now beginning to see patterns emerging from these studies. These include significant heterogeneity in the rate of recombination that affects adaptive evolution and base composition, the role of population size in adaptive evolution, and the importance of expansion of gene families in lineage-specific adaptation. Moreover, resequencing of population samples (population genomics) has enabled the identification of the genetic basis of critical phenotypes and cast light on the landscape of genomic divergence during speciation. © 2013 Elsevier Ltd. Source

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