Sökning: "Selective cutting"
Visar resultat 6 - 10 av 12 avhandlingar innehållade orden Selective cutting.
6. Trace analysis of polychlorinated dibenzo-p-dioxines, dibenzofurans and related compounds in environmental matrices
Sammanfattning : In this thesis sample extraction, clean up procedures and quantitative and qualitative analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans and related compounds are discussed, as well as aspects on the sampling of some complex environmental matrices.The matrices are mostly from the aquatic environment but other samples are also dealt with, such as urban and remote air samples, samples from environments with heavy automobile traffic and samples from one municipal incinerator, waste water treatment plants etc. LÄS MER
7. Function and dynamics of woody debris in boreal forest streams
Sammanfattning : The work in this thesis deals with (1) the effects of woody debris on stream channel morphology and retention of organic material, and (2) the dynamics of woody debris and its relation to riparian forest history and composition. The studied stream reaches are situated in mature, productive forests in the boreal zone of Sweden. LÄS MER
8. Determination of Persistent Organic Pollutants in Solid Environmental Samples Using Accelerated Solvent Extraction and Supercritical Fluid Extraction. Exhaustive extraction and sorption/desorption studies of PCBs
Sammanfattning : Human activity is constantly causing environmental problems due to production and release of numerous chemicals. A group of compounds of special concern is persistent organic pollutants (POP). These toxic, lipophilic chemicals have a high chemical and biological stability, and tend to accumulate in the lipid phase of living organisms. LÄS MER
9. Group I Introns and Homing Endonucleases in T-even-like Bacteriophages
Sammanfattning : Homing endonucleases are rare-cutting enzymes that cleave DNA at a site near their own location, preferentially in alleles lacking the homing endonuclease gene (HEG). By cleaving HEG-less alleles the homing endonuclease can mediate the transfer of its own gene to the cleaved site via a process called homing, involving double strand break repair. LÄS MER
10. Microclimate at range margins : Consequences for boreal forest understory species
Sammanfattning : A warmer climate will shift species distributional range margins poleward, but near-ground microclimates may modify these shifts. Cold-adapted northern species at their rear edge may survive locally in microrefugia with a colder microclimate, and warm-adapted southern species at their leading edge may colonize stepping stone habitats with a warmer microclimate. LÄS MER