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P Aronsson

Publications and source records attributed to P Aronsson.

4 recordsLinked to original sources
PubMed2005

Fate of heavy metals after application of sewage sludge and wood-ash mixtures to short-rotation willow coppice.

Short-rotation willow coppice (SRWC), grown on farmland in Sweden for energy-biomass production, was fertilised with sewage sludge and wood-ash mixtures on the basis of the permitted annual phosphorus supply. Two identical experiments were conducted in central Sweden, on two newly harvested commercial SRWC fields. The maximum legally permitted amount of the sludge-ash mixture, sludge only, ash only, and twice the maximum permitted sludge-ash amount, were applied. The aim was to assess the effect of pH changes following treatment, on the ability of SRWC to take up large amounts of Cd and other metals. The remediation effect of SRWC was also studied. Under the experimental conditions applied, uptake by SRWC was unaffected by pH changes. The differences between the amounts of metals experimentally applied, less the uptake by SRWC after a potential harvest, were broadly within the permitted limits. For Cd, a reduction of total amounts in soil was observed.

Adsorption↗
PubMed1995

Evolution of T4-related phages.

Much progress has been made in understanding T-even phage biology in the last 50 years. We now know the entire sequence of T4, encoding nearly 300 genes, only 69 of which have been shown to be essential under standard laboratory conditions; no specific function is yet known for about 140 of them. The origin of most phage genes is unclear, and only 42 genes in T4 have significant similarity to anything currently included in GenBank. Comparative analysis of related phages is now being used to gain insight into both the evolutionary origins and interrelationships of these phage genes, and the functions of their protein products. The genomes of phages isolated from Tbilisi hospitals, Long Island sewage plants, the Denver zoo, and Khabarovsk show basic similarity. However, these phages show substantial insertions and deletions in a number of regions relative to each other, and closer investigation of specific sequences often reveals much more complex relationships. There are only a few cases in T4-related phages in which there is evidence for evolution through DNA duplication. These include the fibrous products of genes 12, 34, and 37; head proteins gp23 and gp24; and the Alt enzyme and its downstream neighbors. T4 also contains 13 apparent relatives of group I and group II intron homing endonucleases. Distal portions of the tail fibers of various T-even phages contain segments closely related to tail-fiber regions of other DNA coliphages, such as Mu, P1, P2, and lambda. Horizontal gene transfer clearly emerges as a major factor in the evolution of at least the tail-fiber regions, where site-specific recombination probably is involved in the exchange of host-range determinants.

Amino Acid Sequence↗
PubMedDate not supplied

Effects of non-synaptic neuronal interaction in cortex on synchronization and learning.

During neural communication by means of action potentials, small electromagnetic (EM) fields are also generated. We use a three layered cortical neural network model to study the effects of EM fields and gap junctions on spatio-temporal network activity. We investigate the possible role of these effects in synchronizing activity, a phenomenon which has been observed in the olfactory cortex and the hippocampus. The simulation results support the notion that fast synchronization of activity in distant parts of the neural network are made possible by means of EM fields and/or gap junctions. The results also indicate that these effects, to a certain extent, are beneficial to system performance.

Action Potentials↗