Eutrophication and recovery of Lake Vesijärvi (south Finland): Diatom frustules in varved sediments over a 30-year period

Lake Vesijärvi was loaded by sewage from the City of Lahti for 60 years until 1976 when the discharge was diverted. Paleolimnological analyses of the varved bottom sediment indicate that the sedimentation rate within the Enonselka basin, the most eutrophic part of the lake, has been as high as 2 cm yr^–1, and total phosphorus accumulation was 20–40 g P m^–2 yr^–1, during the last 20 years. Within the less eutrophic Laitialanselkä basin, the sedimentation rate did not exceed 1 cm yr^–1, and the formation of varved sediment only began at the end of the 1960's, i.e. about 10 years later than in Enonselkä.Planktonic diatom production was highest in the Enonselka basin. The most abundant diatoms in the sediment between 1970–1985 were Asterionella formosa, Aulacoseira islandica and Stephanodiscus spp. Fragilaria crotonensis and Tabellaria fenestrata had low abundances in the middle of the 1970's but increased again at the end of the 1970's. Asterionella formosa and Diatoma elongatum reached their maxima between 1979–1984 when the hypolimnion of the Enonselk/:a basin was aerated artificially. In the Laitialanselkä basin, the production of planktonic diatoms has been lower and the species composition of the diatom community differed from that in Enonselkä. However, at the end of 1980's the total accumulation of diatoms in Laitialanselkä approached levels which were observed at the end of 1950's in Enonselkä, prior to the rapid eutrophication period.The production and thereby the sedimentation of diatoms has decreased towards the end of the 1980's in Enonselkä, indicating reduced nutrient availability in the lake water. This reduction was due to the decreased external loading of phosphorus as well as to the decreased release of phosphorus from the sediment as a result of improved oxygen balance in the hypolimnion.     

Identification of N-acetylneuraminyl alpha 2-->3 poly-N-acetyllactosamine glycans as the receptors of sialic acid-binding Streptococcus suis strains.

Streptococcus suis is a common cause of sepsis, meningitis, and other serious infections in young piglets and also causes meningitis in humans. The cell-binding specificity of sialic acid-recognizing strains of Streptococcus suis was investigated. Treatment of human erythrocytes with sialidase or mild periodate abolished hemagglutination. Hemagglutination inhibition experiments with sialyl oligosaccharides indicated that the adhesin preferred the sequence NeuNAc alpha 2-3Gal beta 1-4Glc(NAc). Resialylation of desialylated erythrocytes with Gal beta 1-3(4)GlcNAc alpha 2-3-sialyltransferase induced a strong hemagglutination, whereas no or only weak hemagglutination was obtained with cells resialylated with two other sialyltransferases. Binding of radiolabeled bacteria to blots of erythrocyte membrane proteins revealed binding to the poly-N-acetyllactosamine-containing components Band 3, Band 4.5, and polyglycosyl ceramides and to glycophorin A. The involvement of glycophorin A as a major ligand was excluded by the strong hemagglutination of trypsin-treated erythrocytes and En(a-) erythrocytes defective in glycophorin A. Sensitivity of the hemagglutination toward endo-beta-galactosidase treatment of erythrocytes and inhibition by purified poly-N-acetyllactosaminyl glycopeptides indicated that the adhesin bound to glycans containing the following structure: NeuNAc alpha 2-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-.     

The good bad wolf—wolf evaluation reveals the roots of the Finnish wolf conflict

This article focuses on the roots of the Finnish wolf conflict by using stakeholder evaluations of the wolf as a tool. The recent growth of the wolf population has highlighted stakeholders’ contradictory objectives and revealed a conflict between the two main stakeholders, conservationists and hunters, in wolf management. The question of hunting emerges as the core of the conflict. The negative evaluation of the wolf by hunters reflects a competitive situation, which is typical of the historical development of wolf management in Finland. In areas with the most abundant wolf populations, hunters view the wolf most negatively. This study clearly demonstrates that the Finnish wolf conflict is rooted in the values of modern society and carries a long historical, practical and ecological background in which humans and wolves compete over resources, mainly the moose. The conflict between hunters and conservationists in wolf management is connected to the appreciation of moose as game and stems from competition between humans and wolves over their prey and the historical presence or absence of the wolf.     

Effects of morning vs. evening combined strength and endurance training on physical performance,sleep and well-being

The aim of the present study was to examine how combined strength and endurance training in the morning and evening influences the adaptations in strength and endurance performance, perception of time management, psychological well-being and sleep. The combined training period lasted for 24 weeks and the participants were divided into the morning training (MG, n = 18), evening training (EG, n = 24) and control groups (CG, n = 10). Isometric leg press force (iLP), maximal oxygen consumption (VO₂max), sleep behavior, fatigue, time management, motivation, self-esteem and health-related quality of life (HRQoL) were assessed. Morning to evening difference in iLP was observed in both MG and EG at Pre and Post, with higher force values in the evening, but not for VO₂max. iLP force increased significantly in EG in the morning (p < 0.001) and evening (p = 0.010). VO₂max increased in MG and EG both in the morning (both p < 0.001) and in the evening (MG: p < 0.001; EG: p = 0.003). Participants of the present study slept 7–8 h per night and the self-reported sleep duration, get-up time and the average time to go to bed were similar between the groups and did not change from Pre to Post. From HRQoL dimensions, the score for bodily pain decreased in MG (p = 0.029) and significant between-group differences were observed for Pre-Post changes in MG and EG (p = 0.001) as well as between MG and CG (p < 0.001). In vitality, a significant between-group difference was observed for Pre to Post changes in MG and EG (p = 0.014). Perception of time management decreased in EG (p = 0.042) but stayed unchanged for MG and CG. For the intrinsic motivation to participate, significant between-group differences were observed for MG and EG (p = 0.033) and between MG and CG (p = 0.032) for Pre to Post changes. Self-esteem improved in MG (p = 0.029) and EG (p = 0.024). The present combined strength and endurance training program performed in the morning and in the evening led to similar improvements in strength and endurance performance. Training in the morning or in the evening did not disrupt the already good sleep behavior and it was able to further increase the self-esteem. Although training in the morning hours may leave more time for free time activities or social life (i.e. family and friends) compared to the evening training, it might be more challenging to stay motivated to participate in prolonged training programs in the morning hours.     

Application of a semi-automatic cartilage segmentation method for biomechanical modeling of the knee joint

Manual segmentation of articular cartilage from knee joint 3D magnetic resonance images (MRI) is a time consuming and laborious task. Thus, automatic methods are needed for faster and reproducible segmentations. In the present study, we developed a semi-automatic segmentation method based on radial intensity profiles to generate 3D geometries of knee joint cartilage which were then used in computational biomechanical models of the knee joint. Six healthy volunteers were imaged with a 3T MRI device and their knee cartilages were segmented both manually and semi-automatically. The values of cartilage thicknesses and volumes produced by these two methods were compared. Furthermore, the influences of possible geometrical differences on cartilage stresses and strains in the knee were evaluated with finite element modeling. The semi-automatic segmentation and 3D geometry construction of one knee joint (menisci, femoral and tibial cartilages) was approximately two times faster than with manual segmentation. Differences in cartilage thicknesses, volumes, contact pressures, stresses, and strains between segmentation methods in femoral and tibial cartilage were mostly insignificant (p > 0.05) and random, i.e. there were no systematic differences between the methods. In conclusion, the devised semi-automatic segmentation method is a quick and accurate way to determine cartilage geometries; it may become a valuable tool for biomechanical modeling applications with large patient groups.     

Mitochondrial DNA variation and the phylogeography of the grey partridge (Perdix perdix) in Europe: from Pleistocene history to present day populations

Abstract For a phylogeographical analysis of European grey partridge (Perdix perdix) we sequenced 390 nucleotides of the 5′ end of the mitochondrial control region (CR) of 227 birds from several localities. The birds were divided into two major clades (western and eastern) which differed in control region 1 (CR1) by 14 nucleotide substitutions (3.6%). For estimation of the time of divergence, the whole CR of 14 specimens was sequenced. The major clades differed by 2.2%, corresponding to an estimated coalescence time of c. 1.1 million years. On CR1, 45 haplotypes were found. Western clade haplotypes were found in France, England, Germany, Poland, Italy and Austria. Eastern clade haplotypes were found in Finland, Bulgaria, Greece, and Ireland. One Finnish population and all Bulgarian and Irish populations were mixed, but only in Bulgaria was the mixing assumed to be natural. Nucleotide and haplotype diversities varied between populations, and both clades showed geographical structuring. The distribution of pairwise nucleotide differences in the eastern clade fitted the expectations of an expanding population. About 80% of the genetic structure in the grey partridge could be explained by the clades. The western clade presumably originates on the Iberian Peninsula (with related subtypes in Italy), and the eastern clade either on the Balkan or Caucasian refugia. Large‐scale hand‐rearing and releasing of western partridges have introduced very few mtDNA marks into the native eastern populations in Finland.     

Postmortem recovery and cryopreservation of spermatozoa from the vas deferens of rhesus macaques (Macaca mulatta)

To determine whether sperm derived from the vas deferens could be retrieved and successfully cryopreserved, testes were collected from 20 rhesus macaques (Macaca mulatta). The males ranged in age from 3 to 19 yr with an average age of 8.5 yr. No sperm was obtained from three animals that were younger than 4 yr. The remaining 17 samples contained sperm with an average sperm cell number of 421.8 ± 88.7 × 10⁶ and an average motility of 72.8 ± 4.4%. After 24 h of culture in TALP medium at 37 °C in 5% CO₂ and 95% air, the overall motility decreased significantly in all samples regardless of treatment. Freezing in TEST (TES-Tris buffer)-yolk buffer containing 6% (vol/vol) glycerol had a significant effect on sperm, reducing the immediate postthaw motility to 42.4% in nontreated samples. Treatment with dibutyryl-cAMP and caffeine further reduced sperm motility after 4 h in fresh sperm (72.8% vs. 50.4%) but increased motility in sperm that had been frozen (14.0% vs. 23.2%). The age of the male did not influence sperm concentration or grade but proved to be a significant factor in determining motility of frozen-thawed treated sperm, with lower motility found in samples from older males. Overall, the study demonstrates that motile sperm can be obtained from postmortem males, although subsequent studies will be needed to determine whether the quality is sufficient to facilitate its use in assisted reproduction.     

The Role of Textured Material in Supporting Perceptual-Motor Functions

Simple deformation of the skin surface with textured materials can improve human perceptual-motor performance. The implications of these findings are inexpensive, adaptable and easily integrated clothing, equipment and tools for improving perceptual-motor functionality. However, some clarification is needed because mixed results have been reported in the literature, highlighting positive, absent and/or negative effects of added texture on measures of perceptual-motor performance. Therefore the aim of this study was to evaluate the efficacy of textured materials for enhancing perceptual-motor functionality. The systematic review uncovered two variables suitable for sub-group analysis within and between studies: participant age (groupings were 18–51 years and 64.7–79.4 years) and experimental task (upright balance and walking). Evaluation of studies that observed texture effects during upright balance tasks, uncovered two additional candidate sub-groups for future work: vision (eyes open and eyes closed) and stability (stable and unstable). Meta-analysis (random effects) revealed that young participants improve performance by a small to moderate amount in upright balance tasks with added texture (SMD = 0.28, 95%CI = 0.46–0.09, Z = 2.99, P = 0.001; Tau² = 0.02; Chi² = 9.87, df = 6, P = 0.13; I² = 39.22). Significant heterogeneity was found in, the overall effect of texture: Tau² = 0.13; Chi² = 130.71, df = 26, P<0.0001; I² = 85.98%, pooled samples in upright balance tasks: Tau² = 0.09; Chi² = 101.57, df = 13, P<0.001; I² = 72.67%, and in elderly in upright balance tasks: Tau² = 0.16; Chi² = 39.42, df = 5, P<0.001; I² = 83.05%. No effect was shown for walking tasks: Tau² = 0.00; Chi² = 3.45, df = 4, P = 0.27, I² = 22.99%. Data provides unequivocal support for utilizing textured materials in young healthy populations for improving perceptual-motor performance. Future research is needed in young healthy populations under conditions where visual and proprioceptive information is challenged, as in high-speed movements, or where use of equipment mediates the performer-environment interaction or where dysfunctional information sources ‘compete’ for attention. In elderly and ailing populations data suggests further research is required to better understand contexts where texture can facilitate improved perceptual-motor performance.     

No genetic evidence of sex-biased dispersal in a lekking bird, the capercaillie (Tetrao urogallus)

Sex-biased dispersal is often connected to the mating behaviour of the species. Even if patterns of natal dispersal are reasonably well documented for monogamous birds, only a few data are available for polygynous and especially lekking species. We investigated the dispersal of the capercaillie (Tetrao urogallus) by examining sex-specific gene flow among the leks. Genetic information was extracted using nuclear and mitochondrial molecular markers for sexed faecal samples and analysed by novel Bayesian statistical methods. Contrary to the traditional view that the males are highly philopatric and female is the dispersing sex, we found roughly equivalent gross and effective dispersal of the sexes. The level of polygamy has a strong influence on the effective population size and on the effective dispersal. The results do not support the theories that dispersal evolves solely as a result of resource competition or other advantages to males obtained through kin selection in lekking species.