Metabarcoding successfully tracks temporal changes in eukaryotic communities in coastal sediments.

Metabarcoding is a method that combines high-throughput DNA sequencing and DNA-based identification. Previously, this method has been successfully used to target spatial variation of eukaryote communities in marine sediments, however, the temporal changes in these communities remain understudied. Here, we follow the temporal changes of the eukaryote communities in Baltic Sea surface sediments collected from two coastal localities during three seasons of two consecutive years. Our study reveals that the structure of the sediment eukaryotic ecosystem was primarily driven by annual and seasonal changes in prevailing environmental conditions, whereas spatial variation was a less significant factor in explaining the variance in eukaryotic communities over time. Therefore, our data suggests that shifts in regional climate regime or large-scale changes in the environment are the overdriving factors in shaping the coastal eukaryotic sediment ecosystems rather than small-scale changes in local environmental conditions or heterogeneity in ecosystem structure. More studies targeting temporal changes are needed to further understand the long-term trends in ecosystem stability and response to climate change. Furthermore, this work contributes to the recent efforts in developing metabarcoding applications for environmental biomonitoring, proving a comprehensive option for traditional monitoring approaches.

Predictors of perceived togetherness in very old men and women: a 5-year follow-up study.

Although a considerable amount of research has been carried out on older adults' social ties, most of it has focused on quantitative aspects and on cross-sectional samples. In this study, the subjective aspect of social interaction is described by the concept of perceived togetherness. The aim of this study was to examine the extent to which different factors predict perceived togetherness in men and women over a 5-year period. It also addresses the question of whether it is possible to identify different subgroups in perceived togetherness. The data were collected with structured interviews and laboratory tests from 225 elderly people at ages 80 and 85. The results showed that the predictors of perceived togetherness partly differed between sexes as well as within the groups of males and females. Predictors common to both genders were contacts with friends, less depressive symptoms, higher education level and better coping with instrumental activities of daily living (IADLs). The findings indicated the importance of friends. Widowhood and self-rated health were predictors in women but not in men. Moreover, there appeared to be two subgroups of women and men in perceived togetherness; these were labeled "socially embedded", "socially isolated", "socially active" and "solitary". The results indicate diversity in perceived togetherness and its predictors. More attention should be paid to individual differences in order to prevent loneliness and to promote older adults' well-being.

Health and functional capacity as predictors of community dwelling among elderly people.

The aim of this study was to identify factors that predict community dwelling (i.e., nonuse of institutional bed-days) among elderly people. This was a longitudinal study of institution use including both short-term and long-term use of hospitals and nursing homes. The impact of health, functional performance, and carrying out the activities of daily living on community dwelling was studied using the method of path analysis. The participants were all the 75-year-old (N = 388) and 80-year-old (N = 291) men and women resident in the City of Jyväskylä, Finland. Predictor variables included disease severity, symptoms of illness, cognitive capacity, walking speed, muscle strength, hearing, and ability to carry out the activities of daily living. The outcome variable was community dwelling. Over 70% of the elderly people had received institutional care during the 5-year follow-up. The path analysis models showed that disease severity and symptoms of illness had an effect on community dwelling: those with a more severe disease or more symptoms needed more institutional care. The effect was also mediated through limitations in physical performance and cognitive capacity and need for assistance in activities of daily living. The explanatory power of these models varied from 23% to 36%. The results of this study suggest that prevention, treatment, and rehabilitation programs aimed at the promotion of community dwelling in elderly people should focus on the severity of diseases, functional performance, and the ability to carry out the activities of daily living.

Environmental changes in the North Atlantic Region: SCANNET as a collaborative approach for documenting, understanding and predicting changes.

The lands surrounding the North Atlantic Region (the SCANNET Region) cover a wide range of climate regimes, physical environments and availability of natural resources. Except in the extreme North, they have supported human populations and various cultures since at least the end of the last ice age. However, the region is also important at a wider geographical scale in that it influences the global climate and supports animals that migrate between the Arctic and all the other continents of the world. Climate, environment and land use in the region are changing rapidly and projections suggest that global warming will be amplified there while increasing land use might dramatically reduce the remaining wilderness areas. Because much of the region is sparsely populated--if populated at all--observational records of past environmental changes and their impacts are both few and of short duration. However, it is becoming very important to record the changes that are now in progress, to understand the drivers of these changes, and to predict future consequences of the changes. To facilitate research into understanding impacts of global change on the lands of the North Atlantic Regions, and also to monitor changes in real time, an EU-funded network of research sites and infrastructures was formed in 2000: this was called SCANNET--SCANdinavian/North European NETwork of Terrestrial Field Bases. SCANNET currently consists of 9 core sites and 5 sites within local networks that together cover the broad range of current climate and predicted change in the region. Climate observations are well replicated across the network, whereas each site has tended to select particular environmental and ecological subjects for intensive observation. This provides diversity of both subject coverage and expertise. In this paper, we summarize the findings of SCANNET to-date and outline its information bases in order to increase awareness of data on environmental change in the North Atlantic Region. We also identify important gaps in our understanding and identify where the roles of existing infrastructures and activities represented by SCANNET can facilitate future research, monitoring and ground-truthing activities.

External quality assessment of serum hormone determinations in the Nordic countries.

Since 1979 the Nordic Clinical Chemistry Project (NORDKEM) has organized four external quality assessment surveys of serum hormone determinations in the five Nordic countries. Charcoal-stripped control sera with weighed additions of the following hormones have been used: thyrotropin, human placental lactogen, prolactin, estriol, estradiol, testosterone, cortisol, triiodothyronine, thyroxine, and, in the fourth survey, progesterone. Human serum was usually used but in the first survey the serum matrix for the protein hormones was calf serum. In three years no systematic improvement in the coefficients of variation of the results has occurred. The change from calf serum to human serum also had no major effects on the results. Percentage coefficients of bias usually varied on both sides of the true value, but at low hormone concentrations the results were almost always positively biased. It is therefore useful to know the true hormone concentrations of the control samples because all-laboratory means are relatively often biased from these. Variation produced by different methods of calculation of the radioimmunoassay results and the influence of outlying standard points on these data processing routines were studied in the third survey. It is possible that sometimes the variation produced by different methods of calculation is one of the main components of the total variation in external quality assessment of RIA. There were no major differences between the performance of computerized or manual calculation methods. The influence of different calibration standards on serum thyroxine determination was studied in the fourth survey. Of the total coefficient of variation (10.8% to 17.0%) the component of variation produced by different thyroxine calibration standards was 0.8% to 4.6%. In conclusion, standardization of the data processing methods and further standardization of assay reagents are urgently needed to give possibilities to identify more subtle differences in the analytical performance of the laboratories. External quality assessment of hormone determinations needs improvement of the quality of reference materials.

External quality assessment of serum drug determinations in the Nordic countries.

A system for external quality assessment of serum drug determinations in the five Nordic countries has been established, and results of several surveys of antiepileptic drug determinations are described. The work was started as a pioneer work of NORDKEM at the time when NORDKEM was founded and was carried out during the years 1977-1979. The problems concerning methodology of drug analyses and, consequently, the problem of setting up quality assessment systems differ clearly from those in connection with the common analyses of clinical chemistry. Especially the quality of control materials is very important. An expert panel of drug specialists is necessary to plan and interpret an external quality assessment program of drug analyses, but it can very well be carried out in connection with other quality assessment programs. The state of the art of antiepileptic drug determinations in the Nordic countries at the time of the surveys was very good. The level of inaccuracy was well below 5%, and the level of imprecision was mainly in the range of 15-20%, although no outliers were excluded during the statistical treatment of the data.

Internal quality control of hormone determinations by RIA. Detection of clinically significant analytical errors of serum thyroxine determination.

An internal quality control system by which clinically significant analytical errors can be detected with high probability was developed for serum thyroxine (T4) determination by RIA. The mean concentration of the quality control samples (C1, C2, and C3) were 40.0, 101.8, and 156.7 nmol/l, and their total standard deviations (st) 2.5, 4.1, and 7.1 nmol/l, respectively, in stable analytical performance of the T4 assay. From the clinical point of view it was accepted that the results of C1 varied from 30 to 50 nmol/l at the most. When expressed in standard deviations, the same size of error was accepted for C2 and C3. It followed that the quality control system had to detect a systematic shift of 2.43st (delta SEc) and a 2.08 times increase in random error (delta REc) in order that the quality goals could be reached. With three control samples the combination of rules, 1: 3s/CS1: (1.0s; 2.7s), which was chosen for manual quality control, detected the delta SEc with about an 80% probability and the delta REc with about a 30% probability. The probability of false rejections was less than 1%. The probability of detecting the delta SEc was considered acceptable, but to detect the delta REc with a higher probability, the within-assay variation of each run was calculated from the results of duplicate patient samples. Although the whole run was not rejected because of systematic and/or random errors, individual samples were reanalysed if the results of their duplicate determinations differed from the criteria stated.(ABSTRACT TRUNCATED AT 250 WORDS)

Present analytical quality in the Nordic clinical chemistry laboratories.

An introductory review is given of the discussion in the Nordic countries on the definition, aim, and optimal organization of quality control. Published and unpublished Scandinavian works have been reviewed and commented under the following headlines: common chemical analyses, enzyme analyses, serum and plasma protein analyses, hormone analyses, drug analyses, hematological tests, and urine analyses. It is concluded that methods for calculating medical standards of analytical quality in clinical chemistry form the logical background for the design of an optimal quality control system, which will guarantee that analytical results well have a specified probability of satisfying the medical requirements.

Assessment of analytical quality in Nordic clinical chemistry laboratories using data from contemporary national programs.

The aim of this investigation was primarily to assess analytical quality expressed as between-laboratory, within-laboratory, and total imprecision, not in order to detect laboratories with poor performance, but in the positive sense to provide data for improving critical steps in analytical methodology. The aim was also to establish the present state of the art in comparison with earlier investigations to see if improvement in analytical quality could be observed.

Testing a model of physical activity and obesity tracking from youth to adulthood: the cardiovascular risk in young Finns study.

OBJECTIVE: To test a potential model of the relationship between physical activity and obesity from youth to adulthood. DESIGN: Longitudinal study data from the cardiovascular risk in young Finns study. SUBJECTS: A total of 1319 boys (n=626) and girls (n=693) aged 9, 12, 15 and 18 years were randomly selected from five university towns and their rural surroundings in 1980. They were followed up for 21 years. In 2001 they were 30, 33, 36 and 39 years old. MEASUREMENTS: Physical activity was assessed by a short questionnaire at two measurement points. Obesity was measured by body mass index (BMI) and sum of skinfolds in 1980 and BMI and waist circumference in 2001. RESULTS: Structural equation analysis (LISREL) indicated that the prevalence of abdominal obesity in adulthood was directly affected by adult physical activity (beta (beta)=-0.16, t=-4.02, P< 0.05 for men, beta=-0.12, t=-3.35, P<0.05 for women) and indirectly via youth physical activity (beta=-0.10, t=-4.68, P< 0.05 for men, beta=-0.07, t=-4.54, P<0.05 for women). Obesity tracked significantly from youth to adulthood (beta=0.41, t=11.13, P<0.05 for men, beta=0.34, t=9.39, P<0.05 for women). Youth physical activity might reduce body weight in youth but was not directly associated with adult abdominal obesity in either men or women. The model accounted 19% of abdominal obesity in men and 13% in women. The path from youth physical activity to adult obesity through youth obesity seemed to be stronger than the path through adult physical activity. CONCLUSIONS: This study lends general support to the hypothesized model that abdominal obesity in adulthood is directly related to adult physical activity and youth overall obesity in both sexes. Youth physical activity had an indirect effect on abdominal obesity through the maintenance of physical activity in adulthood. Participation in and maintaining physical activity from youth to adulthood may have an important role in reducing obesity in adulthood.

Evolution of the ITS sequences of ribosomal DNA in Enteromorpha (Chlorophyceae).

Ribosomal DNA (rDNA) region, including the 3' end of the 18S rRNA gene, the entire 5.8S rRNA gene, the 5' end of the 28S rRNA gene, and the internal transcribed spacers ITS 1 and ITS 2, of Enteromorpha green algae from the Baltic Sea, were sequenced. The evolution of the Enteromorpha sequences differed from those of other green algae in several important ways. The ITS regions were short and had a high nucleotide bias. The frequency of nucleotides G and C was up to 70% in the ITS sequences, whereas the frequencies were close to 50% in the 5.8S rDNA. Furthermore, the sequence divergence was much higher in ITS 1 than in ITS 2. Two haplotypes, differing only by two nucleotides, were detected in the E. intestinalis/compressa complex. The difference coincides with a morphological differentiation (branching of thalli) and may represent distinct gene pools.

Latent Structure Analysis of Longitudinal Data on Relations Between Intellectual Abilities and School Achievement.

Covariance structure modelling by LISREL was applied to analyze the relations between intellectual ability, as measured by ITPA, and achievement in reading, writing, foreign language and mathematics in longitudinal data with 8 to 10 years' time interval between measurements. The subjects' (N = 234) ability scores were obtained at 5-7 years of age, and their achievement was measured at 14-16 years of age. The effect of ability to achievement was studied by analyzing structural equation models on both first-order ability and achievement factors and by developing a two-stage second-order factor estimation method for structural equation parameters between first-order ability and achievement factors. Squared multiple correlations and coefficients of determination as indices of explained variance were derived for reduced forms of structural equations. The general latent intellectual ability explained 49% of variance in school achievement. The results showed the high validity of ITPA in explaining school success as well as the great flexibility and usefulness of covariance structure modelling by LISREL in analyzing longitudinal data.

Stability of habitual physical activity and sport participation: a longitudinal tracking study.

Although one of the most important aims of physical education and public sport policy is to encourage life-long habitual physical activity, very little is known of the stability or tracking of physical activity. As a part of a larger research project called Cardiovascular Risks in Young Finns, the purpose of the study reported here was to investigate the stability (tracking) of leisure-time physical activity and sport participation at intervals of 3, 6, 9 and 12 years from age 9 to 30. The subjects, chosen by stratified random sample, represent five geographical areas of the country and eight gender-age cohorts (9, 12, 15 and 18 years old in 1980). Physical activity and sport participation were measured using a short questionnaire. Tracking was analysed by Spearman's rank order correlations and by simplex model. The tracking correlations within a 3-year interval of all individual variables were significant but rather low. The tracking correlations of the sum index of physical activity comprising five variables varied from 0.50 to 0.80 among boys and from 0.40 to 0.61 among girls. Simplex models that fitted the data very well showed higher stability coefficients than rank order correlations. With one exception the correlations of physical activity index within the 12-year interval were significant but low.

Do neighboring lakes share common taxa of bacterioplankton? Comparison of 16S rDNA fingerprints and sequences from three geographic regions.

Bacterioplankton community composition was studied in 12 lakes in three different geographic regions in Scandinavia using denaturing gradient gel electrophoresis (DGGE) and sequencing of 16S rDNA. Area-specific abundant taxa were found in the lakes in two of the regions. In the region of Uppland the lakes had an alpha-proteobacterium, belonging to the subgroup Alpha V in common. The Alpha V bacteria appeared to be favored by neutral or higher pH values. The lakes in Lappland were found to harbor Actinobacteria, which appeared to be favored in bog lakes. No abundant taxon was found to be in common for the lakes in Svalbard, the third region studied.

Phylogeographical structure, distribution and genetic variation of the green algae Ulva intestinalis and U. compressa (Chlorophyta) in the Baltic Sea area.

The marine algae Ulva intestinalis and U. compressa are morphologically plastic with many overlapping characters and are therefore difficult to distinguish from each other. The present distribution of U. intestinalis and U. compressa is investigated along the salinity gradient in the Baltic Sea area through analyses of internal transcribed spacer (ITS) sequence data. Also, the amount and distribution of intraspecific genetic polymorphism in the ITS region is studied allowing inferences on the phylogeographical pattern and postglacial recolonization of the Baltic Sea area. The data show that of the two species only U. intestinalis occurs in the Baltic Sea. The distribution of U. compressa is more restricted than previously reported, and it was not found in salinities lower than 15 ppt. All of Scandinavia and the Baltic Sea were covered with ice during the last ice age and the organisms in the Baltic Sea must have colonized the area after the ice had started to melt. The genetic diversity of U. intestinalis and U. compressa in the Baltic Sea and the neighbouring area was found to be reduced compared to that in the British Isles. This reduction may be the result of either a historical reduction of diversity or an adaptation of specific clones to the northern environmental conditions.

Gas-liquid chromatographic determination of mexiletine in human serum with nitrogen sensitive detection.

A simple and rapid method for the quantitative determination of mexiletine, using gas-liquid chromatography with nitrogen sensitive detection, is described. Only one extraction step is needed, the recovery is between 92-96% and the precision varies between 2.0--5.5%. The lower limit of detection reached 0.5 micro mol/1. During routine handling the method was easy, quick and cheap.

Predicting physical activity intentions using a goal perspectives approach: a study of Finnish youth.

Physical activity intentions were studied in 12- to 16-year-old Finnish girls (n= 186) and boys (n=215). Theoretical predictions were used to establish a model that was then tested separately for each sex using path analysis. Firstly, it was hypothesised that malleable conceptions of the nature of sport ability positively influence enjoyment in physical activity and intentions to participate in physical activity, mediated by a task-oriented achievement goal independent of variations in perceptions of competence. Secondly, it was hypothesised that fixed conceptions of the nature of ability decrease enjoyment in physical activity and intentions to participate, mediated by an ego-oriented achievement goal and by perceived competence. The modified models were shown to fit the data. Overall, the results showed that 63% (boys) and 45% (girls) of the variance in intentions was explained by the model. The motivational importance of task orientation and, among the boys, perceived physical competence was confirmed with their direct prediction of intentions.

Self-rated health and associated factors among men of different ages.

The connections of certain clinico-physiological indicators of health state, chronic diseases, felt symptoms, and psychic well-being with self-rated health were studied among men of different ages as a part of the more extensive research project Jyväskylä Studies on Functional Aging. Study population was selected by using systematic random sampling among men aged 31 to 35, 51 to 55 and 71 to 75 years in the city of Jyväskylä. Log-linear and logit models as well as regression and structural equation models within the framework of LISREL were used as methods of analysis. The associations between general self-rated health and the explanative variables were different in different age groups: In the youngest age group self-rated health was best explained by symptoms and index of physical fitness; among the middle-aged by symptoms and psychic well-being; and among the oldest by chronic diseases. The results suggest that self-rated health belongs to the important indicators of health, and more attention should be paid to it both in research and in medical practice.