1,080 research outputs found

    Gene flow of common ash (<em>Fraxinus excelsior</em> L.) in a fragmented landscape

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    Gene flow dynamics of common ash (Fraxinus excelsior L.) is affected by several human activities in Central Europe, including habitat fragmentation, agroforestry expansion, controlled and uncontrolled transfer of reproductive material, and a recently introduced emerging infectious disease, ash dieback, caused by Hymenoscyphus fraxineus. Habitat fragmentation may alter genetic connectivity and effective population size, leading to loss of genetic diversity and increased inbreeding in ash populations. Gene flow from cultivated trees in landscapes close to their native counterparts may also influence the adaptability of future generations. The devastating effects of ash dieback have already been observed in both natural and managed populations in continental Europe. However, potential long-term effects of genetic bottlenecks depend on gene flow across fragmented landscapes. For this reason, we studied the genetic connectivity of ash trees in an isolated forest patch of a fragmented landscape in Rösenbeck, Germany. We applied two approaches to parentage analysis to estimate gene flow patterns at the study site. We specifically investigated the presence of background pollination at the landscape level and the degree of genetic isolation between native and cultivated trees. Local meteorological data was utilized to understand the effect of wind on the pollen and seed dispersal patterns. Gender information of the adult trees was considered for calculating the dispersal distances. We found that the majority of the studied seeds (55-64%) and seedlings (75-98%) in the forest patch were fathered and mothered by the trees within the same patch. However, we determined a considerable amount of pollen flow (26-45%) from outside of the study site, representing background pollination at the landscape level. Limited pollen flow was observed from neighbouring cultivated trees (2%). Both pollen and seeds were dispersed in all directions in accordance with the local wind directions. Whereas there was no positive correlation between pollen dispersal distance and wind speed, the correlation between seed dispersal distance and wind speed was significant (0.71, p < 0.001), indicating that strong wind favours long-distance dispersal of ash seeds. Finally, we discussed the implications of establishing gene conservation stands and the use of enrichment planting in the face of ash dieback

    Statsfængslet i Nyborg: 50 år den 12/7 1963

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    Digital support interventions for the self-management of low back pain: a systematic review

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    Background: Low back pain (LBP) is a common cause of disability and is ranked as the most burdensome health condition globally. Self-management, including components on increased knowledge, monitoring of symptoms, and physical activity, are consistently recommended in clinical guidelines as cost-effective strategies for LBP management and there is increasing interest in the potential role of digital health. Objective: The study aimed to synthesize and critically appraise published evidence concerning the use of interactive digital interventions to support self-management of LBP. The following specific questions were examined: (1) What are the key components of digital self-management interventions for LBP, including theoretical underpinnings? (2) What outcome measures have been used in randomized trials of digital self-management interventions in LBP and what effect, if any, did the intervention have on these? and (3) What specific characteristics or components, if any, of interventions appear to be associated with beneficial outcomes? Methods: Bibliographic databases searched from 2000 to March 2016 included Medline, Embase, CINAHL, PsycINFO, Cochrane Library, DoPHER and TRoPHI, Social Science Citation Index, and Science Citation Index. Reference and citation searching was also undertaken. Search strategy combined the following concepts: (1) back pain, (2) digital intervention, and (3) self-management. Only randomized controlled trial (RCT) protocols or completed RCTs involving adults with LBP published in peer-reviewed journals were included. Two reviewers independently screened titles and abstracts, full-text articles, extracted data, and assessed risk of bias using Cochrane risk of bias tool. An independent third reviewer adjudicated on disagreements. Data were synthesized narratively. Results: Of the total 7014 references identified, 11 were included, describing 9 studies: 6 completed RCTs and 3 protocols for future RCTs. The completed RCTs included a total of 2706 participants (range of 114-1343 participants per study) and varied considerably in the nature and delivery of the interventions, the duration/definition of LBP, the outcomes measured, and the effectiveness of the interventions. Participants were generally white, middle aged, and in 5 of 6 RCT reports, the majority were female and most reported educational level as time at college or higher. Only one study reported between-group differences in favor of the digital intervention. There was considerable variation in the extent of reporting the characteristics, components, and theories underpinning each intervention. None of the studies showed evidence of harm. Conclusions: The literature is extremely heterogeneous, making it difficult to understand what might work best, for whom, and in what circumstances. Participants were predominantly female, white, well educated, and middle aged, and thus the wider applicability of digital self-management interventions remains uncertain. No information on cost-effectiveness was reported. The evidence base for interactive digital interventions to support patient self-management of LBP remains weak

    Long-Term Cardiovascular Health After Pregnancy in Danish Women With Congenital Heart Disease. A Register-Based Cohort Study Between 1993 and 2016

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    Background Little is known about the impact of pregnancy on long‐term cardiovascular health in individuals with congenital heart disease (CHD). We aimed to determine if giving birth in patients with CHD is associated with higher risk of long‐term cardiovascular morbidity. Methods and Results We studied a cohort of 1262 individuals with CHD giving birth (live or still) from 1993 to 2015 using Danish nationwide registers. We randomly sampled a comparison cohort matched on age of women with CHD who had not given birth at the time. We balanced the 2 cohorts on baseline demographic (eg, education) and clinical variables (eg, CHD severity) using inverse probability of treatment weighting. Individuals were followed for critical (eg, heart failure), other cardiovascular morbidity (eg, arrhythmia), and cardiac surgery/interventions after pregnancy. Individuals were followed for median 6.0 years (interquartile range 3.2–9.2). Among individuals giving birth the incidence rate per 1000 person‐years was 1.6, 10.0, and 6.0 for critical and other cardiovascular morbidity and cardiac surgery, respectively. There was no overall difference in risk of neither critical and other cardiovascular morbidity nor cardiac surgery among individuals who gave birth and individuals who did not; adjusted hazard ratios (aHR) were 0.74 (95% CI, 0.37–1.48), 0.88 (95% CI, 0.65–1.19), and 0.78 (95% C,I 0.54–1.12), respectively. However, individuals with obstetric complications had a higher long‐term risk of other cardiovascular morbidity (aHR, 1.85; 95% CI, 1.07–3.20). Conclusions Giving birth seemed not to be associated with a higher risk of long‐term cardiovascular morbidity among women with CHD. However, individuals having obstetric complications had a higher risk of other cardiovascular morbidity in the long term

    Action spectroscopy of chlorophyll and other coordination complexes

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    Action spectroscopy provides key insights into the nature of electronic transitions of coordination complexes such as porhyrin-containing biochromophores like chlorophyll or transition metal complexes such as tris(bipyridine)ruthenium
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