University of Aberdeen

About: University of Aberdeen is a education organization based out in Aberdeen, United Kingdom. It is known for research contribution in the topics: Population & Health care. The organization has 21174 authors who have published 49962 publications receiving 2105479 citations. The organization is also known as: Aberdeen University.

Nitrogen storage and remobilization by trees: ecophysiological relevance in a changing world

Abstract: Summary The role of carbon (C) and nitrogen (N) storage by trees will be discussed in terms of uncoupling their growth from resource acquisition. There are profound differences between the physiology of C and N storage. C storage acts as a short-term, temporary buffer when photosynthesis cannot meet current sink demand and remobilization is sink driven. However, the majority of C allocated to non-structural carbohydrates such as starch is not reused so is in fact sequestered, not stored. In contrast, N storage is seasonally programmed, closely linked to tree phenology and operates at temporal scales of months to years, with remobilization being source driven. We examine the ecological significance of N storage and remobilization in terms of regulating plant N use efficiency, allowing trees to uncouple seasonal growth from N uptake by roots and allowing recovery from disturbances such as browsing damage. We also briefly consider the importance of N storage and remobilization in regulating how trees will likely respond to rising atmospheric carbon dioxide concentrations. Most studies of N storage and remobilization have been restricted to small trees growing in a controlled environment where 15 N can be used easily as a tracer for mineral N. We highlight the need to describe and quantify these processes for adult trees in situ where most root N uptake occurs via ectomycorrhizal partners, an approach that now appears feasible for deciduous trees through quantification of the flux of remobilized N in their xylem. This opens new possibilities for studying interactions between N and C allocation in trees and associated mycorrhizal partners, which are likely to be crucial in regulating the response of trees to many aspects of global environmental change.

Evidence-Based Implementation of Evidence-Based Medicine

Abstract: Article-at-a-Glance Background The slow and haphazard process of translating research findings into clinical practice compromises the potential benefits of clinical research. Most quality improvement (QI) initiatives are based on the beliefs of decision makers rather than on the growing theoretical and empirical knowledge about organizational and provider behavior change. If future QI activities are to improve the translation of evidence into practice, they should be based on an understanding of the different models and strategies for implementing research evidence and the evidence base supporting their use. Evidence-based medicine should be complemented by evidence-based implementation. The evidence for different strategies of implementing change A general framework for changing practice based on theoretical perspectives and research evidence considers a variety of theoretical approaches and their contribution to an understanding of provider behavior change. The framework summarizes evidence from systematic reviews of provider behavior change, which suggest the potential of several dissemination and implementation strategies that are effective under certain conditions. Passive dissemination approaches are largely ineffective; specific strategies to implement research-based recommendations appear to be necessary to ensure practice change. Multifaceted interventions that address specific barriers to change are more likely to lead to changes in practice. Practical, five-stage framework A practical, five-stage framework for changing practice, which is illustrated with experiences from a comprehensive program on implementing evidence-based clinical guidelines in primary care, includes development of a concrete proposal for change; analysis of the target setting and group to identify obstacles to change; linking interventions to needs, facilitators, and obstacles to change; development of an implementation plan; and monitoring progress with implementation.

Gastro-oesophageal reflux symptoms, oesophagitis and Barrett’s oesophagus in the general population: the Loiano–Monghidoro study

Abstract: OBJECTIVE Existing endoscopy-based data on gastro-oesophageal reflux disease (GORD) in the general population are scarce. This study aimed to evaluate typical symptoms and complications of GORD, and their associated risk factors, in a representative sample of the Italian population. METHODS 1533 adults from two Italian villages were approached to undergo symptom assessment using a validated questionnaire and upper gastrointestinal endoscopy. Data were obtained from 1033 individuals (67.4% response rate). RESULTS The prevalence of reflux symptoms was 44.3%; 23.7% of the population experienced such symptoms on at least 2 days per week (frequent symptoms). The prevalence rates of oesophagitis and Barrett's oesophagus in the population were 11.8% and 1.3%, respectively. Both frequent (relative risk (RR) 2.6; 95% confidence interval (CI) 1.7 to 3.9) and infrequent (RR 1.9; 95% CI 1.2 to 3.0) reflux symptoms were associated with the presence of oesophagitis. No reflux symptoms were reported by 32.8% of individuals with oesophagitis and 46.2% of those with Barrett's oesophagus. Hiatus hernia was associated with frequent reflux symptoms and oesophagitis, and was present in 76.9% of those with Barrett's oesophagus. We found no association between body mass index and reflux symptoms or oesophagitis. CONCLUSIONS GORD is common in Italy, but the prevalence of Barrett's oesophagus in the community is lower than has been reported in selected populations. Both frequent and infrequent reflux symptoms are associated with an increased risk of oesophagitis. Individuals with oesophagitis and Barrett's oesophagus often have no reflux symptoms.

Strategies for feeding the world more sustainably with organic agriculture

Abstract: Organic agriculture is proposed as a promising approach to achieving sustainable food systems, but its feasibility is also contested. We use a food systems model that addresses agronomic characteristics of organic agriculture to analyze the role that organic agriculture could play in sustainable food systems. Here we show that a 100% conversion to organic agriculture needs more land than conventional agriculture but reduces N-surplus and pesticide use. However, in combination with reductions of food wastage and food-competing feed from arable land, with correspondingly reduced production and consumption of animal products, land use under organic agriculture remains below the reference scenario. Other indicators such as greenhouse gas emissions also improve, but adequate nitrogen supply is challenging. Besides focusing on production, sustainable food systems need to address waste, crop–grass–livestock interdependencies and human consumption. None of the corresponding strategies needs full implementation and their combined partial implementation delivers a more sustainable food future.