| 1. |
- Clark, Andrew G., et al.
(författare)
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Evolution of genes and genomes on the Drosophila phylogeny
- 2007
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 450:7167, s. 203-218
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Tidskriftsartikel (refereegranskat)abstract
- Comparative analysis of multiple genomes in a phylogenetic framework dramatically improves the precision and sensitivity of evolutionary inference, producing more robust results than single-genome analyses can provide. The genomes of 12 Drosophila species, ten of which are presented here for the first time (sechellia, simulans, yakuba, erecta, ananassae, persimilis, willistoni, mojavensis, virilis and grimshawi), illustrate how rates and patterns of sequence divergence across taxa can illuminate evolutionary processes on a genomic scale. These genome sequences augment the formidable genetic tools that have made Drosophila melanogaster a pre-eminent model for animal genetics, and will further catalyse fundamental research on mechanisms of development, cell biology, genetics, disease, neurobiology, behaviour, physiology and evolution. Despite remarkable similarities among these Drosophila species, we identified many putatively non-neutral changes in protein-coding genes, non-coding RNA genes, and cis-regulatory regions. These may prove to underlie differences in the ecology and behaviour of these diverse species.
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| 2. |
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| 3. |
- McKenna, P., et al.
(författare)
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Lateral electron transport in high-intensity laser-irradiated foils diagnosed by ion emission
- 2007
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Ingår i: Physical Review Letters. - 1079-7114. ; 98:14
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Tidskriftsartikel (refereegranskat)abstract
- An experimental investigation of lateral electron transport in thin metallic foil targets irradiated by ultraintense (>= 10(19) W/cm(2)) laser pulses is reported. Two-dimensional spatially resolved ion emission measurements are used to quantify electric-field generation resulting from electron transport. The measurement of large electric fields (similar to 0.1 TV/m) millimeters from the laser focus reveals that lateral energy transport continues long after the laser pulse has decayed. Numerical simulations confirm a very strong enhancement of electron density and electric field at the edges of the target.
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| 4. |
- Carroll, DC, et al.
(författare)
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Active manipulation of the spatial energy distribution of laser-accelerated proton beams
- 2007
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Ingår i: Physical Review E (Statistical, Nonlinear, and Soft Matter Physics). - 1539-3755. ; 76:065401(R), s. 1-065401
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Tidskriftsartikel (refereegranskat)abstract
- The spatial energy distributions of beams of protons accelerated by ultrahigh intensity (>10^19 W/cm2) picosecond laser pulse interactions with thin foil targets are investigated. Using separate, low intensity (<10^13 W/cm2) nanosecond laser pulses, focused onto the front surface of the target foil prior to the arrival of the high intensity pulse, it is demonstrated that the proton beam profile can be actively manipulated. In particular, results obtained with an annular intensity distribution at the focus of the low intensity beam are presented, showing smooth proton beams with a sharp circular boundary at all energies, which represents a significant improvement in the beam quality compared to irradiation with the picosecond beam alone.
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| 5. |
- Clarke, R. J., et al.
(författare)
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Detection of short lived radioisotopes as a fast diagnostic for intense laser-solid interactions
- 2006
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 89:14
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Tidskriftsartikel (refereegranskat)abstract
- As a diagnostic of high-intensity laser interactions (> 10(19) W cm(-2)), the detection of radioactive isotopes is regularly used for the characterization of proton, neutron, ion, and photon beams. This involves sample removal from the interaction chamber and time consuming post shot analysis using NaI coincidence counting or Ge detectors. This letter describes the use of in situ detectors to measure laser-driven (p,n) reactions in Al-27 as an almost real-time diagnostic for proton acceleration. The produced Si-27 isotope decays with a 4.16 s half-life by the predominantly beta+ emission, producing a strong 511 keV annihilation peak. (c) 2006 American Institute of Physics.
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| 6. |
- Dabek, M, et al.
(författare)
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alpha-ketoglutarate (AKG) absorption from pig intestine and plasma pharmacokinetics
- 2005
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Ingår i: Journal of Animal Physiology and Animal Nutrition. - : Wiley. - 0931-2439 .- 1439-0396. ; 89:11-12, s. 419-426
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Tidskriftsartikel (refereegranskat)abstract
- To study the absorption, metabolism and kinetics, the AKG ( in different concentrations) was administered intravenously, intra-portally, orally and directly into the ileum or duodenum of pigs, chronically fitted with portal and jugular catheters and T-shaped cannula at the duodenum and ileum. Additionally, this study was conducted to determine the influence of low pH, Fe2+ or/ and SO42- on AKG gut absorption and conversely FeSO4 and FeSO4/AKG on Fe2+ gut absorption. It is concluded that AKG was significantly better absorbed from the upper small intestine than from the distal sections. Furthermore, low pH, Fe2+ and/or SO42- ions enhanced AKG absorption. The AKG administered to the portal vein was rapidly eliminated from the blood (half-life less than 5 min). The short lifetime for AKG is probably dependent on quick metabolism in the enteorcyetes and liver. However, the prolonged half-life can be related to its low AKG blood concentration. The Fe2+ concentrations in blood increased after FeSO4 and FeSO4/AKG duodenal infusion. The implication of above observations is important for practical application of the AKG in animal and human nutrition as well in medicine.
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| 7. |
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| 8. |
- Filip, R, et al.
(författare)
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The absorption, tissue distribution and excretion of enteraly administered alpha-ketoglutarate in rats.
- 2008
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Ingår i: Journal of Animal Physiology and Animal Nutrition. - : Wiley. - 0931-2439 .- 1439-0396. ; 92:2, s. 182-189
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Tidskriftsartikel (refereegranskat)abstract
- The absorption, tissue distribution and excretion of enteral alpha-ketoglutarate (AKG) was studied in four experiments. Six male Sprague Dawley rats were used to investigate the excretion of AKG in urine and faeces. Thirty rats, randomly assigned to five groups, were used to investigate the distribution of AKG in body tissues. They were gavaged with AKG enriched with 3 muCi/kg BW of (14)C uniformly marked AKG. Fourteen male Sprague Dawley rats were used to study the absorption of AKG (duodenum vs. ileum). Intestinal recovery of NaAKG vs. CaAKG was investigated in 36 rats. There was no significant excretion of non-metabolized AKG in the urine and faeces. There was no significant difference in the systemic levels of AKG when comparing the proximal to distal small intestine infusion. Up to 50%, 30% and 20% of gastrically delivered AKG was recovered in the stomach, 0.5, 1 and 2 h after gavage; the jejunal recovery achieved a maximum of 3%, 30 min after gavage, and was not detectable 2 h later. There was a relatively high distribution of (14)C-AKG in the tissues (e.g. liver, brain, bones, skin, muscles), 3 h after gavage, up to 70% of the administered dose. In conclusion, the high rate of retention of the carbon from AKG allows the postulation that there is a non-energetic mode of metabolism of intragastrically administered AKG. After conversion to final metabolites, AKG penetrates into all tissues and organs of rats, including the bone tissue. Intestinal absorption of AKG does not depend on the type of AKG salt administered.
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| 9. |
- Högnabba, Filip, et al.
(författare)
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Evolution of cyanobacterial symbioses in Ascomycota.
- 2009
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Ingår i: Biodiversity and Ecology of lichens. Liber Amicorum Harrie Sipman. Bibliotheca Lichenologica. - 1436-1698. - 9783443580780 ; 99, s. 163-184
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Two fifths of the species in Ascomycota are lichen-forming, of which 10% and 3-4% have cyanobacteria as the primary and secondary photobionts respectively. To study the evolution of cyanobacterial symbioses, the phylogenetic relationships within the Ascomycota have been reconstructed. Phylogenetic analyses were made using direct optimization of nuclear SSU and LSU rDNA sequences under the parsimony optimality criterion. Our results indicate repeated evolution of the mutualistic assemblages between fungi and cyanobacteria. The stability of the cyanobacterial symbioses and the effects of photobiont alteration on the evolution of ascomycetes are discussed, as is the taxonomy of some cyanobacterial lichen taxa, and some future perspectives on the evolution of these ecologically important assemblages.
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| 10. |
- Högnabba, Filip, et al.
(författare)
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Phylogenetic relationships and evolution of photobiont associations in the Lobariaceae (Peltigerales, Lecanoromycetes, Ascomycota)
- 2009
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Ingår i: Bibliotheca Lichenologica. Diversity of Lichenology - Anniversary Volume.. - 1436-1698. ; 100, s. 157-187
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Phylogenetic relationships of the family Lobariaceae (Lecanoromycetes, Ascomycota) were reconstructed using direct optimization of nuclear ITS and LSU, and mitochondrial SSU rDNA sequences. Delimitations of the genera currently included in the family were investigated. Relationships of austral temperate taxa occurring in New Zealand, Australia and southern South America were studied in detail. Finally, we studied the evolution of the symbiotic associations found in the family which proved to be monophyletic. Sticta, with the exception of S. oroborealis, but including Dendriscocaulon dendroides, was found to be monophyletic while the genera Lobaria and Pseudocyphellaria turned out to be non-monophyletic. The status of Lobariella, and Lobarina as independent genera was not supported. Relationships of southern temperate Sticta species indicate a common Gondwanan ancestor. In rest of the family, species from the austral temperate zone group together with more widespread species. The ancestor of the Lobariaceae was associated with cyanobacteria. Green algal photobionts have subsequently been acquired repeatedly, but also repeatedly lost within the family. The acquisition of green algae has not resulted in a complete loss of the cyanobacterial photobiont. The cyanobacterial symbioses therefore seem to be more stable than those with green algae.
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