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A significant number of Enterococcus strains from pristine waters of two brooks in Finland formed a distinct cluster on the basis of whole-cell protein fingerprinting by one-dimensional SDS-PAGE. The strains shared the following characteristics. Cells were ovoid, Gram-positive-staining and non-spore-forming, appearing singly or in pairs or chains. They were facultatively anaerobic and catalase-negative. Growth in broth containing 6.5 % NaCl or at 45 °C was weak or absent. Production of D antigen was variable. The strains tolerated 60 °C for 30 min, 40 % bile and tellurite, hydrolysed aesculin strongly and gelatin weakly, produced no acid from hippurate and did not reduce it, grew weakly at 10 °C, showed a strong reaction for the Voges-Proskauer test and produced acid from methyl α-d-glucoside, mannitol, sorbitol and sucrose, with weak or no production of acid from methyl α-d-mannoside, l-arabinose, gluconate and l-xylose. Several of the strains were selected for identification on the basis of sequencing of almost the whole 16S rRNA gene and partial atpA and pheS genes and of (GTG)(5)-PCR fingerprints. Partial atpA and pheS gene sequencing was also performed for those type strains of Enterococcus species without available sequences in the database. The pristine brook isolates formed a novel species, for which the name Enterococcus rivorum sp. nov. (type strain S299(T) = HAMBI 3055(T) = LMG 25899(T) = CCM 7986(T)) is proposed. On the basis of 16S rRNA gene sequence similarity, E. rivorum sp. nov. is related to the Enterococcus faecalis genogoup. It is distinguished from described Enterococcus species on the basis of 16S rRNA, atpA and pheS gene sequences and whole-cell protein and (GTG)(5)-PCR fingerprints. It is most closely related to E. faecalis, but DNA-DNA hybridization confirms it to represent a novel species.

According to theory, directional female choice for male sexual ornaments is expected to erode underlying genetic variation. Considerable attention, in this regard, has been given to understanding the ubiquity of heritable genetic variation in both female choice and male sexual traits. One intriguing possibility emerging from this work is that persistent genetic variation could be maintained, over time, by variation in female mate preferences. Here, we report the results of a four-year study showing significant year-to-year fluctuations in mate preferences in a small marine fish, the sand goby, Pomatoschistus minutus. Although the average size of mature fish varied across years, we were unable to find direct evidence linking this variation to differences in female preferences among years. Our results, nevertheless, underscore the importance of temporal fluctuations in female mate preferences, as these can have important consequences for understanding variation in sexual traits and the intensity of sexual selection.

Trade-offs between current and future reproduction shape life histories of organisms, e.g. increased mortality selects for earlier reproductive effort, and mate limitation has been shown to shape male life histories. Here, we show that female life histories respond adaptively to mate limitation. Female common gobies (Pomatoschistus microps) respond to a female-biased operational sex ratio by strongly increasing the size of their first clutch. The plastic response is predicted by a model that assumes that females use the current competitive situation to predict future difficulties of securing a mating. Because female clutch size decisions are much more closely linked to population dynamics than male life-history traits, plastic responses to mate-finding limitations may be an underappreciated force in population dynamics.

Filial cannibalism (the consumption of one's own offspring) is thought to represent an adaptive strategy in many animals. However, little is known about the details of which offspring are consumed when a parent cannibalizes. Here, we examined patterns of within-brood filial cannibalism in the sand goby (Pomatoschistus minutus). Males spawned sequentially with two females, and we asked whether males cannibalized selectively with regard to egg size or the order in which eggs were received. Males preferentially consumed the larger eggs of the second female they spawned with. Because larger eggs took longer to hatch, and because female 2's eggs were up to 1 day behind those of female 1, such preferential cannibalism might allow males to decrease the time spent caring for the current brood and re-enter the mating pool sooner. More work is needed to understand the fitness consequences of such selective cannibalism.

A collection of 50 indigenous meta-toluate tolerating bacteria isolated from oil-contaminated rhizosphere of Galega orientalis on selective medium was characterized and identified by classical and molecular methods. 16S rDNA partial sequencing showed the presence of five major lineages of the Bacteria domain. Gram-positive Rhodococcus, Bacillus and Arthrobacter and gram-negative Pseudomonas were the most abundant genera. Only one-fifth of the strains that tolerated m-toluate also degraded m-toluate. The inoculum Pseudomonas putida PaW85 was not found in the rhizosphere samples. The ability to degrade m-toluate by the TOL plasmid was detected only in species of the genus Pseudomonas. However, a few Rhodococcus erythropolis strains were found which were able to degrade m-toluate. A new finding was that Pseudomonas migulae strains and a few P. oryzihabitans strains were able to grow on m-toluate and most likely contained the TOL plasmid. Because strain specific differences in degradation abilities were found for P. oryzihabitans, separation at the strain level was important. For strain specific separation (GTG)5 fingerprinting was the best method. A combination of the single locus ribotyping and the whole genomic fingerprinting techniques with the selective partial sequencing formed a practical molecular toolbox for studying genetic diversity of culturable bacteria in oil-contaminated rhizosphere.

Kin selection is a powerful tool for understanding cooperation among individuals, yet its role as the sole explanation of cooperative societies has recently been challenged on empirical grounds. These studies suggest that direct benefits of cooperation are often overlooked, and that partner choice may be a widespread mechanism of cooperation. Female eider ducks (Somateria mollissima) may rear broods alone, or they may pool their broods and share brood-rearing. Females are philopatric, and it has been suggested that colonies may largely consist of related females, which could promote interactions among relatives. Alternatively, shared brood care could be random with respect to relatedness, either because brood amalgamations are accidental and nonadaptive, or through group augmentation, assuming that the fitness of all group members increases with group size. We tested these alternatives by measuring the relatedness of co-tending eider females in enduring coalitions with microsatellite markers. Females formed enduring brood-rearing coalitions with each other at random with respect to relatedness. However, based on previous data, partner choice is nonrandom and dependent on female body condition. We discuss potential mechanisms underlying eider communal brood-rearing decisions, which may be driven by the specific ecological conditions under which sociality has evolved in this species.

Eutrophication as a result of human activity has resulted in increased algal blooms and turbidity in aquatic environments. We investigated experimentally the effect of algal turbidity on the mating system and sexual selection in the sand goby, Pomatoschistus minutus (Pallas), a marine fish with a resource-defence mating system and paternal care. Owing to male-male competition and female choice, large males can monopolize multiple mates, while some males do not achieve mating at all. We show that the number of eggs laid was the same in both turbid and clear tanks but that mating success was more evenly distributed among males in turbid than in clear water. The opportunity for sexual selection was lower in turbid conditions. In turbid conditions mating success was less skewed towards large males. Our results suggest that increased turbidity can change mating systems and decrease the opportunity for sexual selection as well as selection intensity.

During 1997-1999, we collected serum samples from 156 common eider (Somateria mollissima) females incubating eggs in the Finnish archipelago of the Baltic Sea. We used serum chemistry profiles to evaluate metabolic changes in eiders during incubation and to compare the health and nutritional status of birds nesting at a breeding area where the eider population has declined by over 50% during the past decade, with birds nesting at two areas with stable populations. Several changes in serum chemistries were observed during incubation, including (1) decreases in serum glucose, total protein, albumin, beta-globulin, and gamma-globulin concentrations and (2) increases in serum uric acid, creatine kinase, and beta-hydroxybutyrate concentrations. However, these changes were not consistent throughout the 3-yr period, suggesting differences among years in the rate of carbohydrate, lipid, and protein utilization during incubation. The mean serum concentrations of free fatty acids, glycerol, and albumin were lowest and the serum alpha- and gamma-globulin levels were highest in the area where the eider population has declined, suggesting a role for nutrition and diseases in the population dynamics of Baltic eiders.

We report here the results of phylogenetic analysis of archaeal 16S rRNA gene sequences amplified by PCR with Archaea-specific primers with mixed-population DNA extracted directly from forest soil used as a template. Nucleotide signature and phylogenetic analyses show that the sequences obtained belong to the domain Archaea and form a new cluster. Its phylogenetic position suggests that sequences are from a previously undescribed terrestrial group within the kingdom Crenarchaeota.

Objectives: The role of personality characteristics and psychological distress in the incidence of sciatic pain was investigated in a 3-year prospective study., Methods: The study population consisted of 1149 Finnish men aged 25 through 49 years (387 machine operators, 336 carpenters, and 426 office workers) with no history of sciatic pain at the beginning of follow-up. The psychological distress and personality characteristics were assessed by the Middlesex Hospital Questionnaire and the Maudsley Personality Inventory., Results: The 3-year cumulative incidence rate for sciatic pain was 22% among the machine operators, 24% among the carpenters, and 14% among the office workers. The multivariate analysis of psychological factors, taking into account individual and occupational factors, showed that only hysteria was significantly associated with the incidence of sciatic pain among the blue-collar workers. Among the white-collar workers, none of the psychological dimensions were associated with sciatic pain., Conclusions: These results are in accordance with previous relationships found between hysteria and low-back disorders. Further follow-up investigations are needed to elucidate the role of psychological factors in the occurrence of back problems.

Long-term exposure to solvents has been shown to induce neuropsychiatric disorders in workers. In this case-referent study the cases comprised 374 construction workers who had been awarded a disability pension due to a neuropsychiatric disorder in 1978-1980. Their matched referents were selected from construction workers who had been granted a pension due to o ther diseases in the same three-year period. The results of this study indicate that solvent exposure increases the risk of being prematurely pensioned due to neuroses, but early pensioning due to alcoholism or other neuropsychiatric disorders is not increased by solvent exposure. This same conclusion has been reached in earlier studies on this matter in other countries.

This presentation summarizes the characteristics determining the psychological end state after long-term solvent exposure. It also presents the results of research on changes in psychological functions after long-term solvent exposure. Such factors as differential vulnerability and environmental influences other than solvent exposure at work and elsewhere affect the end state. The results of five different Finnish studies are summarized. These studies concerned workers with solvent poisoning, car painters exposed to solvent mixtures, rayon viscose workers exposed to carbon disulfide, printers exposed to toluene, and laminators exposed to styrene. Intellectual functions, short-term memory, and sensory and motor functions were inspected. Verbal intelligence was lowered only in cases of intoxication and exposure to mixtures of organic solvents. Visuoconstructive abilities were deteriorated in those groups with verbal intelligence deterioration, and also among both rayon viscose workers with solvent poisoning and car painters. The group exposed to styrene showed functional changes only in visuomotor accuracy. Lowered manual or finger dexterity was found among workers exposed to carbon disulfide, workers with solvent poisoning, and car painters. The most disturbances were accumulated among those exposed to mixtures of organic solvents.

The psychological prognosis of 86 patients (40 men and 46 women) with previously diagnosed chronic solvent intoxication due to trichloroethylene, perchloroethylene, or solvent mixtures was studied after a follow-up period (mean 5.9 years). The patients' mean age at the time of diagnosis was 38.6 years, and the mean duration of solvent exposure was 10.7 years. Tests for intelligence, short-term memory, and sensory and motor functions were applied. The group means of the patients' intellectual functions were increased after the follow-up period. At the group level, the scores on one sensorimotor task and tasks requiring manual dexterity were lower. Individual patients performed better, worse, or equally when the results of the initial examination and the reexamination were compared. The overall prognosis of psychological test results was better with a longer follow-up period and lower age. Patients who used drugs with neurological effects had a poorer overall psychological prognosis. The characteristic of solvent exposure were related only to the prognosis of some single tests for sensory and motor functions.

Seventy-two male house painters in maintenance work (aged from 35 to 44 a) with a mean of 20.2 a of painting experience were submitted to electroencephalographic (EEG) and electroneurographic examinations; 77 concrete reinforcement workers of similar ages served as the referents. The average long-term exposure level of the painters corresponded to 40 cm3/m3 of white spirit. Altogether six motor conduction velocities and seven sensory conduction velocities were measured for each subject. The frequency of abnormal EEGs among the painters was similar to that found for a normal population or for the referents, namely, 15% of the painters showed a mild and 1% a moderately severe EEG abnormality. The means of the nerve conduction velocities were similar among the painters and referents and also close to the means of the normal material of the laboratory. Slightly slowed nerve conduction velocities suggestive of peripheral nerve dysfunction were found in 20% of both the painters and the referents. This exposure level did not affect the EEG noticeably. A few subjects with abnormally slow nerve conduction velocities may have been affected by occupational factors, either chemical or physical, but the solvent-exposed workers did not differ from their referents in this regard.