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Niche segregation may prevent competitive exclusion and promote local coexistence. This typically results in the occupation of different habitats. In the freshwater ostracod Eucypris virens (Jurine, 1820), the distribution of sexual and parthenogenetic populations in the temporary Lake Caracuel, central Spain, was not homogeneous. Parthenogens were found everywhere including the littoral, whereas sexuals were restricted to the centre. We investigated the hypothesis that spatial distribution responded to ecological differences. We studied the ecological significance of this segregation by linking environmental data to male presence, sexual fraction, ploidy, and genetic structure of our model organism in 12 ponds in the lake basin. Hydro-chemical and biological data indicated that the observed segregation is not only spatial but also ecological, with sexual E. virens occurring in ponds with shorter and probably more unpredictable hydroperiod. The correlations between environmental gradients and E. virens population structure suggest that sexual and parthenogenetic lineages are ecologically segregated. Sexual populations appeared restricted to sufficiently unpredictable environments, while parthenogens dominated environments with longer hydroperiods. Local coexistence seems mediated by spatial heterogeneity in habitat stability. Key words: coexistence, niche segregation, sex, parthenogenesis, habitat permanence, polyploidy, egg bank, Eucypris virens. La segregation de niche peut empecher l'exclusion competitive et promouvoir la coexistence locale. En decoule, typiquement, l'occupation d'habitats differents. Chez l'ostracode d'eau douce Eucypris virens (Jurine, 1820), la distribution des populations sexuelles et parthenogenetiques dans le lac temporaire Caracuel, en Espagne Centrale, n'etait pas homogene. Les parthenogenetiques furent trouves partout y compris sur le littoral, alors que les sexuelles etaient restreintes au centre. Nous investiguons l'hypothese que la distribution spatiale reponde a des differences ecologiques. Nous etudions la signification ecologique de cette segregation en mettant les donnees environnementales en relation avec la presence de males, la proportion sexuelle, la ploidie et la structure genetique de notre organisme modele dans 12 mares du bassin lacustre. Nos donnees hydro-chimiques et biologiques indiquent que la segregation observee n'est pas seulement spatiale mais aussi ecologique, les E. virens sexuels se trouvant dans des mares dont l'hydroperiode est plus courte et probablement plus imprevisible. Les correlations entre les gradients environnementaux et la structure de la population d'E. virens suggerent que ses lignees sexuelles et asexuelles sont ecologiquement segreguees. Les populations sexuelles apparaissent restreintes aux environnements suffisamment imprevisibles, alors que les parthenogenetiques dominent dans les hydroperiodes longues. Une coexistence locale semble favorisee par une heterogeneite dans la stabilite de l'habitat. Mots-cles: coexistence, segregation de la niche, sexe, parthenogenese, permanence de l'habitat, polyploidie, reserve d'ceufs, Eucypris virens., Introduction The phenomenon where sexual populations are restricted to a core area while parthenogenetic lineages occupy a wider geographic range is termed geographic parthenogenesis (Vandel 1928). It has been described [...]

A study assesses primary (after hatching) and secondary (after juvenile mortality) outcrossing rates of two mixed-mating snail populations in order to investigate the variation in mating-system parameters and estimate significance of inbreeding depression for secondary outcrossing rate. Results show that outcrossing rate is much more variable among families in the population with the lower average outcrossing rate, suggesting that individuals differ considerably in the mating system.

The South Anchorage Snow Disposal and Sedimentation Basin in Alaska was developed to treat water discharges from commercial, industrial and residential areas including runoff from snow-disposal sites. The project was developed in compliance with EPA's National Pollutant Discharge Elimination System program requiring a permit for a separate stormwater sewer system to control urban runoff. The sedimentation basin and wetland complex was expected to minimize the turbidity observed in local streams.

The adult and metacercaria life stages of a new species of the microphallid genus Atriophallophorus Deblock & Rosé, 1964 are described from specimens collected at Lake Alexandrina (South Island, New Zealand). In addition to molecular analyses of ribosomal and mitochondrial genes, metacercariae of Atriophallophorus winterbourni n. sp. from the snail host Potamopyrgus antipodarum (Gray) were grown in vitro to characterize internal and external morphology of adults using light and scanning electron microscopy and histological techniques. Atriophallophorus winterbourni n. sp. is readily distinguishable from Atriophallophorus coxiellae Smith, 1973 by having a different structure of the prostatic chamber, sub-circular and dorsal to genital atrium, rather than cylindrical, fibrous, elongate and placed between the seminal vesicle and the genital atrium. The new species is most similar to Atriophallophorus minutus (Price, 1934) with regards to the prostatic chamber and the morphometric data, but possesses elongate-oval testes and subtriangular ovary rather than oval and transversely oval in A. minutus. Phylogenetic analyses including sequence data for A. winterbourni n. sp. suggested a congeneric relationship of the new species to a hitherto undescribed metacercariae reported from Australia, both forming a strongly supported clade closely related to Microphallus and Levinseniella. In addition, we provide an amended diagnosis of Atriophallophorus to accommodate the new species and confirm the sinistral interruption of the outer rim of the ventral sucker caused by the protrusion of the dextral parietal atrial scale at the base of the phallus. [ABSTRACT FROM AUTHOR]

The amount and the quality of 3D spatial data are growing constantly, but the data is collected and stored in a distributed fashion by various data collecting organizations. This may lead to problems regarding interoperability, usability and availability of the data. Traditionally, national spatial data infrastructures have focused on 2D data, but recently there has been great progress towards introducing also 3D spatial data in governmental services. This paper studies the process of creating a country-wide 3D data repository in Finland and visualizing it for the public by using an open source map application. The 3D spatial data is collected and stored into one national topographic database that provides information for the whole society. The data quality control process is executed with an automated data quality module as a part of the import process to the database. The 3D spatial data is served from the database for the visualization via 3D service and the visualization is piloted in the National Geoportal. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the clinical findings, treatment and outcome of patients with major salivary gland symptoms treated with sialendoscopy. The study investigated the medical records of 228 consecutive patients who underwent sialendoscopy between January 2011 and December 2013 in Helsinki, Finland. The results showed some improvement in patients with signs of chronic inflammation without salivary stones but they experienced relapse.

Probiotic bifidobacteria are widely used in the prevention of childhood diseases. These bacteria are also associated with caries occurrence. The present secondary analysis in a low-caries population evaluated the effect of early administration of Bifidobacterium animalis subsp. lactis BB-12 (BB-12) on caries occurrence and identified markers of dental decay in early childhood. In the original randomized, double-blind, placebo-controlled study (NCT00638677, http://www.clinicaltrials.gov), infants (n = 106) received BB-12, xylitol or sorbitol tablets from the age of 1-2 months to 2 years with a slow-release pacifier or a spoon (daily dose of BB-12 1010 colony-forming units, polyol 200-600 mg). The present data were collected using clinical examinations and questionnaires at the age of 4 years. The occurrence of dental caries was assessed using the International Caries Detection and Assessment System. Oral hygiene status and mutans streptococci (MS) levels were also determined. No differences were detected between the study groups in the occurrence of enamel caries (p = 0.268) or obvious dentinal caries (p = 0.201). The occurrence of caries was associated with daily consumption of sweet drinks (p = 0.028), visible plaque observed (p = 0.002) and MS detected in the dental plaque (p = 0.002). Administration of BB-12 in infancy does not seem to increase or decrease the occurrence of caries by 4 years of age in a low-caries population. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A 3-year-old Cairn Terrier dog that had been in contact with sea water containing cyanobacteria (blue-green algae) was euthanized because of acute hepatic failure and anuria after a 5-day illness. Histologic findings included lytic and hemorrhagic centrilobular hepatocellular necrosis and renal tubular necrosis. The cyanotoxin nodularin was detected in liver and kidney by high-performance liquid chromatography–mass spectrometry. Nodularin is a potent hepatotoxin produced by the algal species Nodularia spumigena. The intensity of algal blooms has increased during the past decades in the Baltic Sea region, thus increasing the risk for intoxications in domestic and wild animals. The authors describe the pathologic findings of cyanobacterial toxicosis in a dog with direct identification of the toxin from organ samples. [ABSTRACT FROM PUBLISHER]

A randomized clinical trial studied the effects of early ad-ministration of Bifidobacterium animalis subsp. lactis BB-12 (BB-12) on oral colonization of (1) mutans streptococci (MS), and (2) BB-12. In this double-blind, placebo-controlled study, infants (n = 106) received probiotic bacteria (BB-12 group), xylitol (X group), or sorbitol (S group). Test tablets were administered twice a day (from the age of 1-2 months) with a novel slow-release pacifier or a spoon (daily dose of BB-12 1010 CFU, polyol 200-600 mg). Samples were collected from mucosa/teeth at the age of 8 months and 2 years for BB- 12 determination (qPCR) and plate culturing of MS (MSB, TYCSB), lactobacilli (Rogosa) and yeasts (Sabouraud). The MS levels of the mothers were determined (Dentocult SM Strip Mutans). The baseline characteristics of the three groups were similar. Mean duration of tablet delivery was 14.9 ± 6.7 months. In all groups, >90% of the mothers showed high MS counts (log CFU ≥5). MS colonization percentages of the children at the age of 2 years were rather low (BB-12 group: 6%; X group: 31%; S group: 10%; p < 0.05). The levels of lactobacilli and yeasts did not differ between the groups. BB-12 cell counts barely exceeding the detection limit were found in three of the oral samples of the 8-month-old children; however, the 2-year samples did not contain BB-12. The early administration of BB-12 did not result in permanent oral colonization of this probiotic or significantly affect MS colonization in the children. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

BACKGROUND: Psychosocial climate at school reported by school personnel may be related to pupils' reports of being heard at school, depression, physical and psychological symptoms, truancy and received health education. METHODS: Cross-sectional study combining data from two independent surveys conducted between 2004 and 2005 in 136 public schools in Finland. The pupil sample comprised 11 583 boys and 12 706 girls from the eighth and ninth grades of lower secondary school and first and second grades of upper secondary school. A personnel survey (n = 1946) was used to measure psychosocial climate indexed by trust and opportunity for participation, support for innovation, orientation towards high-quality work and accepted and clear goals. RESULTS: After adjustment for individual and school-level covariates, multilevel analyses revealed odds for pupils' opinion of not being heard were higher in schools where personnel reported poor trust and opportunity for participation (OR = 1.33) and low support for innovation (OR = 1.37). Poor trust and opportunity for participation and unclear work goals among staff were associated with high truancy among pupils (ORs = 1.54 and 1.39). Poor trust and opportunity for participation among staff were also related to pupils' depression [cumulative odds ratio (COR = 1.14)], and physical and psychological symptoms (COR = 1.17). Unclear goals among staff were associated with pupils' opinions that health education was insufficient (OR = 1.40). CONCLUSIONS: school climate is associated with adolescents' health, wellbeing and received health education. [ABSTRACT FROM AUTHOR]

A distributed model of anaerobic digestion of solid waste was developed to describe the balance between the rates of polymer hydrolysis and methanogenesis during the anaerobic conversion of rich and lean wastes in batch and continuous-flow reactors. Waste, volatile fatty acids (VFAs), methanogenic biomass and sodium concentrations are the model variables. Diffusion and advection of VFAs inhibiting both polymer hydrolysis and methanogenesis were considered. A sensitivity analysis by changing the key model parameter values was carried out. The model simulations showed that the effective distance between the areas of hydrolysis/acidogenesis and methanogenesis is very important. An initial spatial separation of rich waste and inoculum enhances the methane production and waste degradation at high waste loading if relatively low VFA diffusion into the methanogenic area is taking place. When both hydrolysis and methanogenesis are strongly inhibited by high levels of VFA, fluctuations in biomass concentration are thought to be responsible for initiating the expansion of methanogenic area over the reactor space. [ABSTRACT FROM AUTHOR]

Develops a distributed model of anaerobic digestion of solid waste. Diffusion of volatile fatty acids inhibiting both polymer hydrolysis and acetoclastic methanogenesis; Concentration waves of methanogenic biomass; Optimum conditions for the solid waste digestion.

Equal distribution of health care services has long been a major goal of health policy in the Nordic countries. According to these guidelines, every child is expected to have an examination and treatment at least every second year. The aim of this study was to analyze the trends and, in particular. the socio-economic differences in dental visits between 1977 and 1995. The data were collected as part of a nationwide research program, the Adolescent Health and Lifestyle Survey, which began in 1977. Every second year a self-administered questionnaire was mailed to a representative sample of 14-, 16- and 18-year-old Finns. The sample sizes in the surveys varied from 2422 to 9556. making a total of 56 605 subjects in the whole study. The response rates in different years varied from 77% to 88%. The percentage of adolescents visiting a dentist increased between 1977 and 1981 and thereafter remained stable. Dental visits seemed to correlate with the occupational and educational status of the parents up to 1983, hut not after that. The Finnish primary oral health care policy seems to have gained a major objective by eliminating social inequality in dental service utilization among adolescents. [ABSTRACT FROM AUTHOR]

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Abstract Background Cyanobacteria can form massive toxic blooms in fresh and brackish bodies of water and are frequently responsible for the poisoning of animals and pose a health risk for humans. Anabaena is a genus of filamentous diazotrophic cyanobacteria commonly implicated as a toxin producer in blooms in aquatic ecosystems throughout the world. The biology of bloom-forming cyanobacteria is poorly understood at the genome level. Results Here, we report the complete sequence and comprehensive annotation of the bloom-forming Anabaena sp. strain 90 genome. It comprises two circular chromosomes and three plasmids with a total size of 5.3 Mb, encoding a total of 4,738 genes. The genome is replete with mobile genetic elements. Detailed manual annotation demonstrated that almost 5% of the gene repertoire consists of pseudogenes. A further 5% of the genome is dedicated to the synthesis of small peptides that are the products of both ribosomal and nonribosomal biosynthetic pathways. Inactivation of the hassallidin (an antifungal cyclic peptide) biosynthetic gene cluster through a deletion event and a natural mutation of the buoyancy-permitting gvpG gas vesicle gene were documented. The genome contains a large number of genes encoding restriction-modification systems. Two novel excision elements were found in the nifH gene that is required for nitrogen fixation. Conclusions Genome analysis demonstrated that this strain invests heavily in the production of bioactive compounds and restriction-modification systems. This well-annotated genome provides a platform for future studies on the ecology and biology of these important bloom-forming cyanobacteria.

Abstract Background Extinction and re-colonisation of local populations is common in ephemeral habitats such as temporary streams. In most cases, such population turnover leads to reduced genetic diversity within populations and increased genetic differentiation among populations due to stochastic founder events, genetic drift, and bottlenecks associated with re-colonisation. Here, we examined the spatio-temporal genetic structure of 8 alpine caddisfly populations inhabiting permanent and temporary streams from four valleys in two regions of the Swiss Alps in years before and after a major stream drying event, the European heat wave in summer 2003. Results We found that population turnover after 2003 led to a loss of allelic richness and gene diversity but not to significant changes in observed heterozygosity. Within all valleys, permanent and temporary streams in any given year were not differentiated, suggesting considerable gene flow and admixture between streams with differing hydroperiods. Large changes in allele frequencies after 2003 resulted in a substantial increase in genetic differentiation among valleys within one to two years (1-2 generations) driven primarily by drift and immigration. Signatures of genetic bottlenecks were detected in all 8 populations after 2003 using the M-ratio method, but in no populations when using a heterozygosity excess method, indicating differential sensitivity of bottleneck detection methods. Conclusions We conclude that genetic differentiation among A. uncatus populations changed markedly both temporally and spatially in response to the extreme climate event in 2003. Our results highlight the magnitude of temporal population genetic changes in response to extreme events. More specifically, our results show that extreme events can cause rapid genetic divergence in metapopulations. Further studies are needed to determine if recovery from this perturbation through gradual mixing of diverged populations by migration and gene flow leads to the pre-climate event state, or whether the observed changes represent a new genetic equilibrium.

Abstract Background This study compared parental smoking with school personnel smoking in relation to adolescents' smoking behaviours, alcohol use, and illicit drug use. Methods A cross-sectional survey for 24,379 adolescents was linked to a survey for 1946 school employees in 136 Finnish schools in 2004-2005. Surveys included smoking prevalence reported by school staff, adolescents' reports of school staff and parental smoking, adolescents' own smoking behaviours, alcohol use, and illicit drug use. Multilevel analyses were adjusted for individual and school-level confounding factors. Results Parental smoking was associated with all health risk behaviours among both sexes (risk range 1.39 to 1.95 for other outcomes; Odds Ratio OR for smoking cessation 0.64, 95% Confidence Interval CI: 0.57, 0.72 among boys, 0.72; 0.64, 0.81 among girls). Among boys, high vs. low smoking prevalence among school personnel was associated with higher probability of smoking (OR 1.19; 95% CI 1.01,1.41), higher frequency of smoking during school time (Cumulative Odds Ratio COR 1.81; 95% CI 1.32, 2.48), frequent alcohol use (OR 1.23; 95% CI 1.01, 1.50), illicit drug use (OR 1.40; 95% CI 1.16, 1.69), and higher odds of reporting adults smoking at school (COR 1.51; 95% CI 1.09, 2.09). Among girls, high smoking prevalence among school personnel was related to higher odds of smoking (OR 1.18; 95% CI 1.02, 1.37) and lower odds of smoking cessation (OR 0.84; 95% CI 0.72, 0.99). Conclusion Parental smoking and school personnel smoking are both associated with adolescents' health risk behaviours but the association of parental smoking seems to be stronger.

Abstract Background Cyanobacteria produce a wealth of secondary metabolites, including the group of small cyclic heptapeptide hepatotoxins that constitutes the microcystin family. The enzyme complex that directs the biosynthesis of microcystin is encoded in a single large gene cluster (mcy). mcy genes have a widespread distribution among cyanobacteria and are likely to have an ancient origin. The notable diversity within some of the Mcy modules is generated through various recombination events including horizontal gene transfer. Results A comparative analysis of the adenylation domains from the first module of McyB (McyB1) and McyC in the microcystin synthetase complex was performed on a large number of microcystin-producing strains from the Anabaena, Microcystis and Planktothrix genera. We found no decisive evidence for recombination between strains from different genera. However, we detected frequent recombination events in the mcyB and mcyC genes between strains within the same genus. Frequent interdomain recombination events were also observed between mcyB and mcyC sequences in Anabaena and Microcystis. Recombination and mutation rate ratios suggest that the diversification of mcyB and mcyC genes is driven by recombination events as well as point mutations in all three genera. Sequence analysis suggests that generally the adenylation domains of the first domain of McyB and McyC are under purifying selection. However, we found clear evidence for positive selection acting on a number of amino acid residues within these adenylation domains. These include residues important for active site selectivity of the adenylation domain, strongly suggesting selection for novel microcystin variants. Conclusion We provide the first clear evidence for positive selection acting on amino acid residues involved directly in the recognition and activation of amino acids incorporated into microcystin, indicating that the microcystin complement of a given strain may influence the ability of a particular strain to interact with its environment.

Abstract Background Microcystins are small cyclic heptapeptide toxins produced by a range of distantly related cyanobacteria. Microcystins are synthesized on large NRPS-PKS enzyme complexes. Many structural variants of microcystins are produced simulatenously. A recombination event between the first module of mcyB (mcyB1) and mcyC in the microcystin synthetase gene cluster is linked to the simultaneous production of microcystin variants in strains of the genus Microcystis. Results Here we undertook a phylogenetic study to investigate the order and timing of recombination between the mcyB1 and mcyC genes in a diverse selection of microcystin producing cyanobacteria. Our results provide support for complex evolutionary processes taking place at the mcyB1 and mcyC adenylation domains which recognize and activate the amino acids found at X and Z positions. We find evidence for recent recombination between mcyB1 and mcyC in strains of the genera Anabaena, Microcystis, and Hapalosiphon. We also find clear evidence for independent adenylation domain conversion of mcyB1 by unrelated peptide synthetase modules in strains of the genera Nostoc and Microcystis. The recombination events replace only the adenylation domain in each case and the condensation domains of mcyB1 and mcyC are not transferred together with the adenylation domain. Our findings demonstrate that the mcyB1 and mcyC adenylation domains are recombination hotspots in the microcystin synthetase gene cluster. Conclusion Recombination is thought to be one of the main mechanisms driving the diversification of NRPSs. However, there is very little information on how recombination takes place in nature. This study demonstrates that functional peptide synthetases are created in nature through transfer of adenylation domains without the concomitant transfer of condensation domains.