Publications by authors named "Oksanen T"

Objective: Elevated blood glucose is associated with poor outcome in patients resuscitated from out-of-hospital cardiac arrest (OHCA). Our aim was to determine whether strict glucose control with intensive insulin treatment improves outcome of OHCA patients.

Design: A randomized, controlled trial.

View Article and Find Full Text PDF

Body size at birth has implications for the quality of individuals throughout their life. Although large body size is generally considered an advantage, the relationship between body size at birth and long-term fitness is often complicated. Under spatial or temporal variation in environmental conditions, such as the seasonally changing densities of Fennoscandian vole populations, selection should favor variation in offspring phenotypes, as different qualities may be beneficial in different conditions.

View Article and Find Full Text PDF

Background: Therapeutic hypothermia (TH) has been shown to increase survival after out-of-hospital resuscitation. The aim of our study was to find out nationwide implementation and the actual utilization of TH after cardiac arrest in Finnish intensive care units (ICUs). We also determined the outcomes and describe demographic variables of the patients treated with TH.

View Article and Find Full Text PDF

Sexual selection based on signaling requires that signals used by females in mate choice are reliable indicators of a male's heritable total fitness. A signal and the preference for it are expected to be heritable, resulting in the maintenance of genetic covariance between these two traits. However, a recent article has proposed that signals may quickly become unreliable in the presence of both environmental variation and genotype-by-environment interaction (G x E) with crossing reaction norms, potentially compromising the mechanisms of sexual selection.

View Article and Find Full Text PDF

Because seedlings and mature trees do not necessarily respond similarly to O(3) stress, it is critically important that exposure systems be developed that allow exposure of seedlings through to mature trees. Here we describe three different O(3) Free-Air Exposure Systems that have been used successfully for exposure at all growth stages. These systems of spatially uniform O(3) release have been shown to provide reliable O(3) exposure with minimal, if any, impact on the microclimate.

View Article and Find Full Text PDF

Social environments, like neighbourhoods, are increasingly recognised as determinants of health. While several studies have reported an association of low neighbourhood socio-economic status with morbidity, mortality and health risk behaviour, little is known of the health effects of neighbourhood crime rates. Using the ongoing 10-Town study in Finland, we examined the relations of average household income and crime rate measured at the local area level, with smoking status and intensity by linking census data of local area characteristics from 181 postal zip codes to survey responses to smoking behaviour in a cohort of 23,008 municipal employees.

View Article and Find Full Text PDF

Background: Prior studies on social capital and health have assessed social capital in residential neighbourhoods and communities, but the question whether the concept should also be applicable in workplaces has been raised. The present study reports on the psychometric properties of an 8-item measure of social capital at work.

Methods: Data were derived from the Finnish Public Sector Study (N = 48,592) collected in 2000-2002.

View Article and Find Full Text PDF

We used exogenous gonadotropin hormones to physiologically enlarge litter size in the bank vole (Clethrionomys glareolus). This method allowed the study design to include possible production costs of reproduction and a trade-off between offspring number and body size at birth. Furthermore, progeny rearing and survival and postpartum survival of the females took place in outdoor enclosures to capture salient naturalistic effects that might be present during the fall and early winter.

View Article and Find Full Text PDF

The number of offspring attaining reproductive age is an important measure of an individual's fitness. However, reproductive success is generally constrained by a trade-off between offspring number and quality. We conducted a factorial experiment in order to study the effects of an artificial enlargement of offspring number and size on the reproductive success of female bank voles (Clethrionomys glareolus).

View Article and Find Full Text PDF

Large oscillations in the populations of Norwegian lemmings have mystified both professional ecologists and lay public. Ecologists suspect that these oscillations are driven by a trophic mechanism: either an interaction between lemmings and their food supply, or an interaction between lemmings and their predators. If lemming cycles are indeed driven by a trophic interaction, can we tell whether lemmings act as the resource ('prey') or the consumer ('predator')? In trophic interaction models, peaks of resource density generally have a blunt, rounded shape, whereas peaks of consumer density are sharp and angular.

View Article and Find Full Text PDF

Hypotheses on trophic dynamics in terrestrial ecosystems fall into two major categories: those in which plants are assumed to be invulnerable to their consumers and those in which the build-up of plant biomass is assumed to require top-down control of folivores. The hypothesis of exploitation ecosystems (EEH) belongs to the latter category and focuses particularly on the consequences of the high energetic costs of maintenance of endotherms. Carnivorous endotherms require relatively high prey densities in order to break even.

View Article and Find Full Text PDF

Effects of recycling ECF-bleached softwood kraft pulp on pulp properties were evaluated in the laboratory. The tensile strength, fiber flexibility and WRV lost during drying of the pulp were recovered by refining between the cycles which, however, resulted in deteriorated drainage properties. The recycled pulps were treated with purified Trichoderma reesei cellulases and hemicellulases and the changes in fiber properties due to enzymatic treatments were characterized.

View Article and Find Full Text PDF

Parental investment in reproduction is adjusted according to potential benefits in terms of offspring survival and/or mating success. If male quality affects the reproductive success of a female, then females mating with high-quality males should invest more in reproduction. Although the subject has been of general interest, further experimental verification of the hypothesis is needed.

View Article and Find Full Text PDF

Pikas (Ochotona princeps: Lagomorpha) build caches of vegetation ("haypiles"), which serve as a food source during winter in alpine and subalpine habitats. Haypiles appear to degrade over time and form patches of nutrient-rich soils in barren talus and scree areas. We sampled soils underneath and next to haypiles, and plants growing on and near haypiles in an alpine cirque in northwestern Wyoming, USA, to determine the effects of pika food caches on N, C, and C/N ratios in soils and plants.

View Article and Find Full Text PDF

The significance of hypopigmented skin findings as manifestations of the gene for tuberous sclerosis (TS) in near relatives of TS patients is a difficult problem. We therefore studied the number and kind of whitish skin alterations found in 100 medical students and 100 school children. Ninety three percent of the former and 79% of the latter had some whitish lesions, many of them scars.

View Article and Find Full Text PDF

A placebo-controlled double-blind study was conducted on the efficacy of Lactobacillus GG in preventing travellers' diarrhoea. Altogether 820 persons travelling on holiday to southern Turkey to two destinations were randomized into two groups receiving either Lactobacillus GG or placebo in identical sachets. On the return flight each participant completed a questionnaire indicating the incidence of diarrhoea and related symptoms during the trip.

View Article and Find Full Text PDF