Perhesuhteiden vaikutus nuorten unen kestoon, unen laatuun ja unen ajoittumiseen

Tavoitteet. On laajasti tiedossa, että monet nuoret nukkuvat liian vähän. Tutkimustieto perhesuhteiden vaikutuksesta nuorten uneen on kuitenkin puutteellista. Lisäksi kyseisissä tutkimuksissa käytetyt menetelmät ja koehenkilöiden iät vaihtelevat suuresti ja vain muutama tutkimus on hyödyntänyt aktigrafi-mittausta. Tämän tutkimuksen tarkoituksena on selvittää yhteyttä perhesuhteiden ja nuorten unen, erityisesti unen keston, unen laadun ja unen ajoituksen, välillä. Menetelmät. Tämä tutkimus oli osa Helsingin yliopiston SleepHelsinki! väestöpohjaista tutkimusprojektia. Yhteensä 308 15–18-vuotiaan nuoren (70.5% tyttöjä) unta ja perhesuhteita mitattiin. Unta mitattiin sekä subjektiivisilla (PSQI) että objektiivisilla (aktigrafi) menetelmillä. Perhesuhteiden yhteyttä unen ajoitukseen ja unen laatuun tutkittiin lineaarisilla ja logistisilla regressioilla. Tulokset ja johtopäätökset. Yhteydet perhesuhteiden ja unen keston välillä eivät olleet tilastollisesti merkitseviä. Kun sukupuoli kontrolloitiin, myöskään yhteydet perhesuhteiden ja unen ajoituksen välillä eivät olleet tilastollisesti merkitseviä. Yhteys perhesuhteiden ja subjektiivisen unen laadun välillä oli kuitenkin tilastollisesti merkitsevä ja haastavat perhesuhteet olivat yhteydessä kohonneeseen riskiin kokea oma unen laatu huonoksi. Miessukupuoli sen sijaan oli yhteydessä kohonneeseen haastavan vuorokausirytmin riskiin. Tämän tutkimuksen tulosten perusteella perhesuhteilla on yhteys subjektiiviseen unen laatuun ja haastavat perhesuhteet ovat heikon unenlaadun riskitekijä nuorilla.Aims of the study. It is well known that many adolescents do not get enough sleep. However, there is little research about the possible connection between adolescent sleep and family functioning. In addition, these studies vary greatly in, e.g., methodology and ages of the participants and only a few studies have used actigraphy. The aim of the present study is to examine the associations between family functioning and adolescent sleep, more specifically sleep duration, sleep quality and sleep timing. Methods. The present study was a part of SleepHelsinki!, a population-based research project based in the University of Helsinki. Sleep and family functioning of 308 adolescents (70.5% females), aged 15–18, were measured. Both subjective (PSQI) and objective (actigraphy) measures of sleep were used. Linear and logistic regressions were used to statistically analyze the associations between family functioning and sleep timing and subjective sleep quality. Results and conclusions. The association between family functioning and sleep duration was non-significant. When sex was adjusted for, the association between family functioning and sleep timing remained non- significant. However, the association between subjective sleep quality and general family functioning was statistically significant. Furthermore, problematic family functioning was related to a higher risk of poor sleep quality. Male sex was related to a higher risk of having a challenging circadian rhythm. Based on the results of the present study, family functioning is connected to subjective sleep quality and more problematic family functioning is a risk factor for lower quality sleep in adolescents

Biological processes and links to the physics

Analysis of the temporal and spatial variability of biological processes and identification of the main variables that drive the dynamic regime of marine ecosystems is complex. Correlation between physical variables and long-term changes in ecosystems has routinely been identified, but the specific mechanisms involved remain often unclear. Reasons for this could be various: the ecosystem can be very sensitive to the seasonal timing of the anomalous physical forcing; the ecosystem can be contemporaneously influenced by many physical variables and the ecosystem can generate intrinsic variability on climate time scales. Marine ecosystems are influenced by a variety of physical factors, e.g., light, temperature, transport, turbulence. Temperature has a fundamental forcing function in biology, with direct influences on rate processes of organisms and on the distribution of mobile species that have preferred temperature ranges. Light and transport also affect the physiology and distribution of marine organisms. Small-scale turbulence determines encounter between larval fish and their prey and additionally influences the probability of successful pursuit and ingestion. The impact of physical forcing variations on biological processes is studied through long-term observations, process studies, laboratory experiments, retrospective analysis of existing data sets and modelling. This manuscript reviews the diversity of physical influences on biological processes, marine organisms and ecosystems and their variety of responses to physical forcing with special emphasis on the dynamics of zooplankton and fish stocks

Climate, zooplankton and pelagic fish growth in the Central Baltic Sea

Oceanographic conditions in the brackish central Baltic Sea are strongly linked to atmospheric forcing and the unusual period of persistently strong westerlies that, since the late 1980s, have resulted in an increase in average water temperatures and decreasing salinity. These changes in temperature and salinity resulted in a change in the dominance of the mesozooplankton community from Pseudocalanus sp. to Temora longicornis and Acartia spp. Similar to the copepod community, the central Baltic fish community shifted from cod ( Gadus morhua ), dominant during the 1980s, to sprat ( Sprattus sprattus ), dominant during the 1990s. Further, the commercially important pelagic fish species herring ( Clupea harengus ) and sprat exhibited reductions in growth. Using Principal Component and Correlation Analyses we investigated the temporal variability in the importance of the food supply as well as competition on condition of central Baltic pelagic fish species. Our results indicate that herring condition results from a combined effect of changes in the food environment and increased competition with sprat, while sprat condition appeared to be primarily determined by intra-specific competition

Seasonal occurrence of Loricate Choanoflagellates in Danish inner waters

It is a trend in loricate choanoflagellate research that our knowledge of species diversity is insufficient in terms of understanding annual successional changes at any specific locality, whereas there is a fairly decent coverage worldwide - at least in more coastal realms - in terms of biodiversity within more narrowly defined time windows. To help address this knowledge gap, we have compiled all available loricate choanoflagellate occurrence data from Danish sampling sites covering an overall time span of close to four decades. The close to 100 samples analysed have a good annual coverage and they encompass in total more than 50 species. We demonstrate clear successional trends among well-defined clusters of species. A large contingent of 'non-native' species, which are in a global context largely considered part of the loricate choanoflagellate warm water community, occurred in September 2014 samples from the Baltic Sea entrance, i.e. the Sound between Denmark and Sweden. While the occurrence of these species is likely due to a large inflow of southern Atlantic water, we also discuss whether the findings may instead reflect recent and more permanent climate change-induced alterations to choanoflagellate biodiversity in inner Danish waters. (C) 2016 Elsevier GmbH. All rights reserved

Directional genetic selection by pulp mill effluent on multiple natural populations of three-spined stickleback (Gasterosteus aculeatus)

Contamination can cause a rapid environmental change which may require populations to respond with evolutionary changes. To evaluate the effects of pulp mill effluents on population genetics, we sampled three-spined sticklebacks (Gasterosteus aculeatus) near four pulp mills and four adjacent reference sites and analyzed Amplified Fragment Length Polymorphism (AFLP) to compare genetic variability. A fine scale genetic structure was detected and samples from polluted sites separated from reference sites in multidimensional scaling plots (P < 0.005, 1000 permutations) and locus-by-locus Analysis of Molecular Variance (AMOVA) further confirmed that habitats are significantly separated (FST = 0.021, P < 0.01, 1023 permutations). The amount of genetic variation between populations did not differ between habitats, and populations from both habitats had similar levels of heterozygosity (polluted sites Nei’s Hs = 0.11, reference sites Nei’s Hs = 0.11). Still, pairwise FST: s between three, out of four, pairs of polluted-reference sites were significant. A FST-outlier analysis showed that 21 (8.4%) loci were statistically different from a neutral distribution at the P < 0.05 level and therefore indicated to be under divergent selection. When removing 13 FST-outlier loci, significant at the P < 0.01 level, differentiation between habitats disappeared in a multidimensional scaling plot. In conclusion, pulp mill effluence has acted as a selective agent on natural populations of G. aculeatus, causing a convergence in genotype composition change at multiple sites in an open environment

Status of Biodiversity in the Baltic Sea

The brackish Baltic Sea hosts species of various origins and environmental tolerances. These immigrated to the sea 10,000 to 15,000 years ago or have been introduced to the area over the relatively recent history of the system. The Baltic Sea has only one known endemic species. While information on some abiotic parameters extends back as long as five centuries and first quantitative snapshot data on biota (on exploited fish populations) originate generally from the same time, international coordination of research began in the early twentieth century. Continuous, annual Baltic Sea-wide long-term datasets on several organism groups (plankton, benthos, fish) are generally available since the mid-1950s. Based on a variety of available data sources (published papers, reports, grey literature, unpublished data), the Baltic Sea, incl. Kattegat, hosts altogether at least 6,065 species, including at least 1,700 phytoplankton, 442 phytobenthos, at least 1,199 zooplankton, at least 569 meiozoobenthos, 1,476 macrozoobenthos, at least 380 vertebrate parasites, about 200 fish, 3 seal, and 83 bird species. In general, but not in all organism groups, high sub-regional total species richness is associated with elevated salinity. Although in comparison with fully marine areas the Baltic Sea supports fewer species, several facets of the system's diversity remain underexplored to this day, such as micro-organisms, foraminiferans, meiobenthos and parasites. In the future, climate change and its interactions with multiple anthropogenic forcings are likely to have major impacts on the Baltic biodiversity