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According to honest signalling theory, signals must be costly to produce to retain information about the signaller's quality. The song produced by male birds during breeding is a vocal "ornament" used for intra- and inter-sexual purposes. The energetic cost of this vocal signal remains a contentious issue. We used the doubly labelled water method to measure field metabolic rate by estimating CO2 p
Functions of biologically active molecules are frequently initiated by elementary chemical reactions such as energy and electron transfer, cis-trans isomerizations, and proton transfer. The nature of these reactions generally makes them very fast and efficient, occurring on picosecond and femtosecond timescales. Ultrafast spectroscopy has played an important role in the study of a number of biolog
Dementia has been found to display a more heterogeneous clinical picture than previously recognized. We investigated brain changes on computed tomography (CT) in a clinical dementia population consisting of 67 cases with Alzheimer's disease (AD), 13 with mixed dementia (AD and vascular dementia, VaD), 71 with VaD, and 12 cases that were not demented. Temporal cortical atrophy and atrophy around th
This study presents a method to regenerate molecularly imprinted polymers (MIPs) used for the selective removal of endocrine disrupting compounds from aqueous effluents. Regeneration was based on solvent extraction under UV irradiation to regenerate the polymer and the solvent while destroying the contaminants. Acetone was selected as the best solvent for irradiation of estrone (E1), 17beta-estrad
A novel method of estimating soil microbial P uptake, using P-33 incorporation into the phospholipids in soil microbial biomass, was used in a study of P-competition between plants and microorganisms. The microbial biomass, and thus the competition for the added P-33, was altered by using different glucose treatments in a microcosm set-up. There was obvious competition for P-33, as shown by the ne
Many industrial applications use flame impingement to obtain high heat-transfer rates. An analytical expression for the convective part of the heat transfer of a flame jet to a plate is derived. Therefore, the flame jet is approximated by a hot inert jet. In contradiction with existing convective heat-transfer relations, our analytical solution is applicable not only for large distances between the j
The mechanisms behind the load building capabilities of a hyperbranched polymer (HBP) in polyurethane (PU) foams have been investigated, using microscopy techniques and mechanical analyses. By broadening the traditional uniaxial compression characterization of PU foams to include combined shear deformations and compression behavior, an apparent Poisson ratio of the foam could be obtained in situ.
Phylogenetic relationships of seven cetrarioid lichens – Ahtiana sphaerosporella, Esslingeriana idahoensis, Kaernefeltia merrillii, Tuckermannopsis americana, T. platyphylla, T. subalpina and Vulpicida canadensis – occurring in British Columbia are analysed together with seven other cetrarioid species using parsimony analysis. The phylogenetic hypothesis based on ITS sequences suggest that ascus c
Even though most bird species with a raptorial feeding habit express varying extents of reversed sexual dimorphism (RSD: females bigger than males), the evolutionary basis for its maintenance, as well as its possible secondary consequences for the ecological adaptations of the different sexes, is debated. We studied pairs of tawny owls, Strix aluco (females 20% heavier than males), throughout the
Following the theme of this monograph, this paper discusses a dialectic we perceive to subsist between meaningful use and reflection upon use. This dialectic between experiencing use and reflecting upon experiencing use (or thinking, and thinking about thinking) may be considered in the following way. Each of these elements is subject to change. As reflection triggers change in use, and such chang
A simple N-country specific-factor-type model with imperfectly mobile labour is developed. It is shown that the effects of country-specific productivity shocks hitting a small country have fundamentally asymmetric effects: A positive shock will be accommodated by a moderate wage increase and sizeable in-migration, whereas a negative shock will be accommodated by a significant decrease in wages and
Background-Epidemiological studies indicate a genetic contribution to ischemic stroke risk, but specific genetic variants remain unknown, with the exception of a few rare variants. Recent genome-wide association studies identified and replicated common genetic variants on chromosome 9p21 to confer risk of coronary heart disease. We examined whether these variants are associated with ischemic strok
The aim of this study was to investigate the effect of ethanol exposure on the expression of fos and jun genes. Exposure of human neuroblastoma SH-SY5Y cells to ethanol for 2-4 days caused a dose-dependent increase in c-jun and junD mRNA levels, whereas mRNAs for c-fos, fosB and junB were not detectable in control or ethanol-treated cells. Four days of ethanol exposure also enhanced the AP-1 bindi
Background Ex vivo gene therapy in the central nervous system (CNS) holds great promise for diseases such as the neurodegenerative disorders. However, achieving stable, long-term transgene expression in grafted cells has proven problematic. This study reports the establishment of an in vitro model of transgene down-regulation in cells grafted to the CNS using the immortalized neural progenitor cel
It is difficult to overestimate Paul Meehl's influence on judgment and decision-making research. His 'disturbing little book' (Meehl, 1986, p. 370) Clinical versus Statistical Prediction: A Theoretical Analysis and a Review of the Evidence (1954) is known as an attack on human judgment and a call for replacing clinicians with actuarial methods. More than 40 years later, fast and frugal heuristics
The effects of nine different anionic and cationic micelle-forming surfactants on the viscosity and viscoelasticity of semidilute solutions of hydrophobically modified hydroxyethyl cellulose (HMHEC) were studied. All added surfactants gave rise to the well-established viscosity maximum with increasing surfactant concentration, but the total surfactant concentration at the maximum, as well as the m
