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The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
In the current opioid epidemic, identifying high-risk patients among those with substance and opioid use may prevent deaths. The objective of this study was to determine whether frequent emergency department (ED) use and degree of frequent use are associated with mortality among ED patients with substance and opioid use.
This cohort study used linked population-based ED (National Ambulatory Care Reporting System) and mortality data from Alberta. All adults ≥ 18 years with substance or opioid use-related visits based on diagnostic codes from April 1, 2012, to March 31, 2013, were included (n = 16,389). Frequent use was defined by ≥ 5 visits in the previous year. Outcomes were unadjusted and adjusted (for age, sex, income) mortality within 90 days (primary), and 30 days, 365 days, and 2 years (secondary). To examine degree, frequent use was subcategorized into 5–10, 11–15, 16–20, and > 20 visits.
Frequent users were older, lower income, and made lower acuity visits than non-frequent users. Frequent users with substance use had higher mortality at 365 days (hazard ratio [HR] 1.36 [1.04, 1.77]) and 2 years (HR 1.32 [1.04, 1.67]), but not at 90 or 30 days. Mortality did not differ for frequent users with opioid use overall. By degree, patients with substance use and > 20 visits/year and with opioid use and 16–20 visits/year demonstrated a higher 365-day and 2-year mortality.
Among patients with substance use, frequent ED use and extremely frequent use (> 20 visits/year) were associated with long-term but not short-term mortality. These findings suggest a role for targeted screening and preventive intervention.
Two broad aims drive weed science research: improved management and improved understanding of weed biology and ecology. In recent years, agricultural weed research addressing these two aims has effectively split into separate subdisciplines despite repeated calls for greater integration. Although some excellent work is being done, agricultural weed research has developed a very high level of repetitiveness, a preponderance of purely descriptive studies, and has failed to clearly articulate novel hypotheses linked to established bodies of ecological and evolutionary theory. In contrast, invasive plant research attracts a diverse cadre of nonweed scientists using invasions to explore broader and more integrated biological questions grounded in theory. We propose that although studies focused on weed management remain vitally important, agricultural weed research would benefit from deeper theoretical justification, a broader vision, and increased collaboration across diverse disciplines. To initiate change in this direction, we call for more emphasis on interdisciplinary training for weed scientists, and for focused workshops and working groups to develop specific areas of research and promote interactions among weed scientists and with the wider scientific community.
Procalcitonin appears to be an early and sensitive marker of bacterial infection in a variety of clinical settings. The use of levels of procalcitonin to predict infection in children undergoing cardiac surgery, however, may be complicated by the systemic inflammatory response that normally accompanies cardiopulmonary bypass. The aim of our study was to estimate peri-operative concentrations of procalcitonin in non-infected children undergoing cardiac surgery. Samples of serum for assay of procalcitonin were obtained in 53 patients at baseline, 24, 48, and 72 hours following cardiac surgery. Concentrations were assessed using an immunoluminetric technique. Median concentrations were lowest at baseline at less than 0.5 nanograms per millilitre, increased at 24 hours to 1.8 nanograms per millilitre, maximized at 48 hours at 2.1 nanograms per millilitre, and decreased at 72 hours to 1.3 nanograms per millilitre, but did not return to baseline levels. Ratios of concentrations between 24, 48 and 72 hours after surgery as compared to baseline were 6.15, with 95 percent confidence intervals between 4.60 and 8.23, 6.49, with 95 percent confidence intervals from 4.55 to 9.27, and 4.26, with 95 percent confidence intervals between 2.78 and 6.51, respectively, with a p value less than 0.001. In 8 patients, who had no evidence of infection, concentrations during the period from 24 to 72 hours were well above the median for the group. We conclude that concentrations of procalcitonin in the serum increase significantly in children following cardiac surgery, with a peak at 48 hours, and do not return to baseline within 72 hours of surgery. A proportion of patients, in the absence of infection, had exaggerated elevations post-operatively.
X-ray microtomography is used to nondestructively section printed wiring boards in which conductive anodic filaments (CAFs) had grown, Quantification of the spatial distribution of copper is compared for microtomography and for serial sections obtained in SEM with backscattered electrons. The agreement between the techniques is excellent and indicates that microtomography may be used confidently to follow the subsurface growth of CAFs.
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