296 research outputs found

    Biodiversity patterns of Arctic diatom assemblages in lakes and streams: Current reference conditions and historical context for biomonitoring

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    Comprehensive assessments of contemporary diatom distributions across the Arctic remain scarce. Furthermore, studies tracking species compositional differences across space and time, as well as diatom responses to climate warming, are mainly limited to paleolimnological studies due to a lack of routine monitoring in lakes and streams across vast areas of the Arctic. The study aims to provide a spatial assessment of contemporary species distributions across the circum-Arctic, establish contemporary biodiversity patterns of diatom assemblages to use as reference conditions for future biomonitoring assessments, and determine pre-industrial baseline conditions to provide historical context for modern diatom distributions. Diatom assemblages were assessed using information from ongoing regulatory monitoring programmes, individual research projects, and from surface sediment layers obtained from lake cores. Pre-industrial baseline conditions as well as the nature, direction and magnitude of changes in diatom assemblages over the pastc.200 years were determined by comparing surface sediment samples (i.e. containing modern assemblages) with a sediment interval deposited prior to the onset of significant anthropogenic activities (i.e. containing pre-1850 assemblages), together with an examination of diatoms preserved in contiguous samples from dated sediment cores. We identified several biotypes with distinct diatom assemblages using contemporary diatom data from both lakes and streams, including a biotype typical for High Arctic regions. Differences in diatom assemblage composition across circum-Arctic regions were gradual rather than abrupt. Species richness was lowest in High Arctic regions compared to Low Arctic and sub-Arctic regions, and higher in lakes than in streams. Dominant diatom taxa were not endemic to the Arctic. Species richness in both lakes and streams reached maximum values between 60 degrees N and 75 degrees N but was highly variable, probably reflecting differences in local and regional environmental factors and possibly sampling effort. We found clear taxon-specific differences between contemporary and pre-industrial samples that were often specific to both ecozone and lake depth. Regional patterns of species turnover (beta-diversity) in the pastc.200 years revealed that regions of the Canadian High Arctic and the Hudson Bay Lowlands to the south showed most compositional change, whereas the easternmost regions of the Canadian Arctic changed least. As shown in previous Arctic diatom studies, global warming has already affected these remote high latitude ecosystems. Our results provide reference conditions for future environmental monitoring programmes in the Arctic. Furthermore, diatom taxa identification and harmonisation require improvement, starting with circum-Arctic intercalibrations. Despite the challenges posed by the remoteness of the Arctic, our study shows the need for routine monitoring programmes that have a wide geographical coverage for both streams and lakes

    Pronova Biopharma - Vurdering av utslipp til Sandefjordsfjorden

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    Det er gjort en vurdering av hvordan avløpsvann fra Pronova Biopharma kan påvirke oksygenforholdene i Sandefjordsfjorden. Arbeidet har bl.a. omfattet strømmålinger, oksygenprøver og bruk av modeller. Hovedkonklusjonen er at til vanlig vil utslippet bare i meget liten grad påvirke oksygenforholdene. De viktigste elementene i fjordens oksygenbudsjett varierer med tiden, og høsten er den mest sårbare perioden. Man kan ikke se helt bort fra at et sammentreff av flere ugunstige faktorer da kan skape en periode med en merkbar redusert konsentrasjon (til vannkvalitetsklasse Mindre God) i en lokal vannmasse omkring utslippet. Ingen undersøkelser har imidlertid påvist at dette har skjedd.Pronova Biopharma AS, Sandefjord v/ A.L. Steneru

    Bullying behaviour in schools, socioeconomic position and psychiatric morbidity: a cross-sectional study in late adolescents in Greece

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    <p>Abstract</p> <p>Background</p> <p>Bullying is quite prevalent in the school setting and has been associated with the socioeconomic position and psychiatric morbidity of the pupils. The aim of the study was to investigate the association between bullying and socioeconomic status in a sample of Greek adolescents and to examine whether this is confounded by the presence of psychiatric morbidity, including sub-threshold forms of illness.</p> <p>Methods</p> <p>5,614 adolescents aged 16-18 years old and attending 25 senior high schools were screened and a stratified random sample of 2,427 were selected for a detailed interview. Psychiatric morbidity was assessed with a fully structured psychiatric interview, the revised Clinical Interview Schedule (CIS-R), while bullying was assessed with the revised Olweus bully/victim questionnaire. The following socio-economic variables were assessed: parental educational level and employment status, financial difficulties of the family and adolescents' school performance. The associations were investigated using multinomial logit models.</p> <p>Results</p> <p>26.4% of the pupils were involved in bullying-related behaviours at least once monthly either as victims, perpetrators or both, while more frequent involvement (at least once weekly) was reported by 4.1%. Psychiatric morbidity was associated with all types of bullying-related behaviours. No socioeconomic associations were reported for victimization. A lower school performance and unemployment of the father were significantly more likely among perpetrators, while economic inactivity of the mother was more likely in pupils who were both victims and perpetrators. These results were largely confirmed when we focused on high frequency behaviours only. In addition, being overweight increased the risk of frequent victimization.</p> <p>Conclusions</p> <p>The prevalence of bullying among Greek pupils is substantial. Perpetration was associated with some dimensions of adolescents' socioeconomic status, while victimization showed no socioeconomic associations. Our findings may add to the understanding of possible risk factors for bullying behaviours in adolescence.</p

    MIDA boronates are hydrolysed fast and slow by two different mechanisms

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    MIDA boronates (N-methylimidodiacetic boronic acid esters) serve as an increasingly general platform for small-molecule construction based on building blocks, largely because of the dramatic and general rate differences with which they are hydrolysed under various basic conditions. Yet the mechanistic underpinnings of these rate differences have remained unclear, which has hindered efforts to address the current limitations of this chemistry. Here we show that there are two distinct mechanisms for this hydrolysis: one is base mediated and the other neutral. The former can proceed more than three orders of magnitude faster than the latter, and involves a rate-limiting attack by a hydroxide at a MIDA carbonyl carbon. The alternative 'neutral' hydrolysis does not require an exogenous acid or base and involves rate-limiting B-N bond cleavage by a small water cluster, (H2O)n. The two mechanisms can operate in parallel, and their relative rates are readily quantified by (18)O incorporation. Whether hydrolysis is 'fast' or 'slow' is dictated by the pH, the water activity and the mass-transfer rates between phases. These findings stand to enable, in a rational way, an even more effective and widespread utilization of MIDA boronates in synthesis

    A step forward for understanding the morbidity burden in Guinea: a national descriptive study

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    <p>Abstract</p> <p>Background</p> <p>Little evidence on the burden of disease has been reported about Guinea. This study was conducted to demonstrate the morbidity burden in Guinea and provide basic evidence for setting health priorities.</p> <p>Methods</p> <p>A retrospective descriptive study was designed to present the morbidity burden of Guinea. Morbidity data were extracted from the National Health Statistics Report of Guinea of 2008. The data are collected based on a pyramid of facilities which includes two national hospitals (teaching hospitals), seven regional hospitals, 26 prefectural hospitals, 8 communal medical centers, 390 health centers, and 628 health posts. Morbidity rates were calculated to measure the burden of non-fatal diseases. The contributions of the 10 leading diseases were presented by sex and age group.</p> <p>Results</p> <p>In 2008, a total of 3,936,599 cases occurred. The morbidity rate for males was higher than for females, 461 versus 332 per 1,000 population. Malaria, respiratory infections, diarrheal diseases, helminthiases, and malnutrition ranked in the first 5 places and accounted for 74% of the total burden, respectively having a rate of 148, 64, 33, 32, and 14 per 1,000 population. The elderly aged 65+ had the highest morbidity rate (611 per 1,000 population) followed by working-age population (458 per 1,000 population) and children (396 per 1,000 population) while the working-age population aged 25-64 contributed the largest part (39%) to total cases. The sex- and age-specific spectrum of morbidity burden showed a similar profile except for small variations.</p> <p>Conclusion</p> <p>Guinea has its unique morbidity burden. The ten leading causes of morbidity burden, especially for malaria, respiratory infections, diarrheal diseases, helminthiases, and malnutrition, need to be prioritized in Guinea.</p

    HIV testing within general practices in Europe : A mixed-methods systematic review

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    Funding Information: This work was supported by IWT (Belgium) and the ANRS (France) through the framework of HIVERA JTC 2014. Publisher Copyright: © 2018 The Author(s).Background: Late diagnosis of HIV infection remains a key challenge in Europe. It is acknowledged that general practitioners (GPs) may contribute greatly to early case finding, yet there is evidence that many diagnostic opportunities are being missed. To further promote HIV testing in primary care and to increase the utility of available research, the existing evidence has been synthesised in a systematic review adhering to the PRISMA guidelines. Methods: The databases PubMed, Scopus and Embase were searched for the period 2006-2017. Two authors judged independently on the eligibility of studies. Through a mixed-methods systematic review of 29 studies, we provide a description of HIV testing in general practices in Europe, including barriers and facilitators. Results: The findings of the study show that although various approaches to target patients are used by GPs, most tests are still carried out based on the patient's request. Several barriers obstruct HIV testing in general practice. Included are a lack of communication skills on sexual health, lack of knowledge about HIV testing recommendations and epidemic specificities, difficulties with using the complete list of clinical HIV indicator diseases and lack of experience in delivering and communicating test results. The findings also suggest that the provision of specific training, practical tools and promotion programmes has an impact on the testing performance of GPs. Conclusions: GPs could have an increased role in provider-initiated HIV-testing for early case finding. To achieve this objective, solutions to the reported barriers should be identified and testing criteria adapted to primary healthcare defined. Providing guidance and training to better identify priority groups for HIV testing, as well as information on the HIV epidemic's characteristics, will be fundamental to increasing awareness and testing by GPs.publishersversionPeer reviewe

    Training future generations to deliver evidence-based conservation and ecosystem management

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    1. To be effective, the next generation of conservation practitioners and managers need to be critical thinkers with a deep understanding of how to make evidence-based decisions and of the value of evidence synthesis. 2. If, as educators, we do not make these priorities a core part of what we teach, we are failing to prepare our students to make an effective contribution to conservation practice. 3. To help overcome this problem we have created open access online teaching materials in multiple languages that are stored in Applied Ecology Resources. So far, 117 educators from 23 countries have acknowledged the importance of this and are already teaching or about to teach skills in appraising or using evidence in conservation decision-making. This includes 145 undergraduate, postgraduate or professional development courses. 4. We call for wider teaching of the tools and skills that facilitate evidence-based conservation and also suggest that providing online teaching materials in multiple languages could be beneficial for improving global understanding of other subject areas.Peer reviewe
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