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Regional Nutrient Budgets in Forest Soils in a Policy Perspective

Popular Abstract in Swedish Skogen är en av Sveriges mest betydelsefulla naturresurser. Utöver det ekonomiska värdet är skogen även viktig ur ett ekologiskt, socialt och kulturellt perspektiv. För att uppnå ett långsiktigt uthålligt skogsbruk måste alla dessa aspekter beaktas. Uthålliga näringsbalanser i den brukade skogsmarken är nödvändiga för att bevara produktionsförmågan samt minska risken föSweden's forests are one of its most important natural resources, as well as being important from ecological and social perspectives. Nutrient sustainability is essential to maintain the production capacity and reduce the effects of acidification and eutrophication. Nutrient sustainability is strongly affected by anthropogenic influences such as air pollution and forestry practices. Regional asses

Denitrification at low temperatures using a suspended carrier biofilm process

The denitrification process was studied in a stirred lab-scale suspended carrier biofilm reactor at low temperatures (3–20°C). The reactor was filled to 50% with Kaldnes K1 carriers. The denitrification rate showed only a rather weak dependence on the temperature, the rate at 3°C being approximately 55% of that at 15°C. The maximum denitrification rate obtained at 15°C was 2.7 g NOx−-N m−2 carrier

Measurement of diffusion coefficients in gel beads: Random and systematic errors

The method of calculating diffusion coefficients in gel beads based on transient experiments of solute uptake from a finite volume has been studied theoretically. Monte Carlo simulation was used to investigate the effect of random errors in the concentration measurements. The influence of sampling frequency and diffusion direction was investigated. Systematic errors derived from an assumption of c

Evaluation of accuracy in activity calculations for the conjugate view method from monte carlo simulated scintillation camera images using experimental data in an anthropomorphic phantom.

Activity determination from scintillation camera images using the conjugate view method may be inaccurate because of variation in scattered radiation from adjacent organs and activity from overlapping tissues. The aim of this study was to simulate patient scintillation camera images and from these evaluate the accuracy of 2 correction methods. The contribution from overlapping tissue activity was

Into the isle of self : Nietzschean patterns and contrasts in D.H. Lawrence's The trespasser

This thesis is based on a close reading of Lawrence's novel The Trespasser from a Nietzschean point of view. By adopting this perspective it aims at giving the novel the sense of unity it has so far been alleged to lack. The analysis is preceded by a detailed discussion of the concept of literary influence. Since the purpose of this study is to illuminate what is unique in Lawrence's novel rather

Bacterial immobilization and remineralization of N at different growth rates and N concentrations

An experiment was designed to resolve two largely unaddressed questions about the turnover of N in soils. One is the influence of microbial growth rate on mobilization and remineralization of cellular N. The other is to what extent heterotrophic immobilization of NO3- is controlled by the soil concentration of NH4+. Bacteria were extracted from a deciduous forest soil and inoculated into an aqueou

The eyes of Macrosoma sp. (Lepidoptera: Hedyloidea): a nocturnal butterfly with superposition optics.

The visual system of nocturnal Hedyloidea butterflies was investigated for the first time, using light and electron microscopy. This study was undertaken to determine whether hedylids possess the classic superposition eye design characteristic of most moths, or apposition eyes of true butterflies (Papilionoidea), and, to gain insights into the sensory ecology of the Hedyloidea. We show that Macros

Quality of life in old people with and without cancer.

The aim was to investigate the influence of age and gender on quality of life (QoL), complaints, and the presence and nature of self-reported diseases in persons aged 75 and older with cancer (n = 150), compared to a matched group without cancer (n = 138). A second aim was to investigate factors associated with poor QoL in people aged 75 and older. QoL was measured with Short Form (SF-12) and Euro

Expression of nitric oxide synthase in bladder smooth muscle cells: Regulation by cytokines and L-arginine

Purpose: The expression and regulation of the different isoforms of nitric oxide synthase (NOS) in bladder smooth muscle cells are controversial and to our knowledge have not yet been studied systematically. Therefore, the expression and regulation of NOS were studied in rat bladder smooth muscle cells after stimulation with cytokines, lipopolysaccharide and L-arginine. Materials and Methods: Prim

Investigating the use of Landsat thematic mapper data for estimation of forest leaf area index in southern Sweden

The study aims at investigating the use of Landsat thematic mapper (TM) for mapping leaf area index (LAI) in coniferous and deciduous forests in southern Sweden. LAI has been estimated in the field with optical measurements, allometric equations, and litter-trap data, and empirical relationships between LAI estimates and satellite-measured reflectances have been analysed. Several common vegetation

Telomere terminating with centromere-specific repeats is closely associated with a transposon derived gene in Chironomus pallidivittatus

We provide evidence that centromere-specific 155 bp DNA repeats terminate one pair of telomeres at the telocentric, left end of the short fourth chromosome in Chironomus pallidivittatus. Earlier evidence indicated that all other telomeres are terminated by 340 bp telomere-specific repeats. DNA that borders the 155 bp repeat contains a transcriptionally active 396 codon open reading frame (ORF) a f

Limitations of the pulse-shape technique for particle discrimination in planar Si detectors

Limitations of the pulse-shape discrimination (PSD) technique - a promising method to identify the charged particles stopped in planar Si-detectors - have been investigated. The particle resolution turned out to be basically determined by resistivity fluctuations in the bulk silicon which cause the charge-collection time to depend on the point of impact. Detector maps showing these fluctuations ha

Subduction-flip during Iapetus Ocean closure and Baltica-Laurentia collision, Scandinavian Caledonides

Evidence is presented here from the northern Scandinavian Caledonides for development of an extensional basin of Ashgill to Mid Llandovery age along the Baltoscandian margin immediately prior to Baltica-Laurentia collision. U/Pb multigrain and ion microprobe zircon dating of plagiogranites in the Halti Igneous Complex complement previous baddeleyite and zircon dating of a dolerite dyke, and zircon