The consequences of nitrogen (N) enrichment for terrestrial and freshwater ecosystems are of increasing concern in many areas due to continued or increasing high emission rates of reactive N. Within terrestrial ecosystems various conceptual frameworks and modelling approaches have been developed which have enhanced our understanding of the sequence of changes associated with increased N availability and help us predict their future impacts. Here, some recent findings are described and their implications for these conceptual frameworks and modelling approaches discussed. They are: (a) an early loss of plant species that are characteristic of low N conditions as N availability increases and a loss of species with high N retention efficiencies (so called N ‘filters’), (b) suppression of microbial immobilisation of deposited \({\text{NO}}^{ - }_{3} \) due to increased \({\text{NH}}^{ + }_{4} \) availability in the early stages of N saturation, (c) the early onset of \({\text{NO}}^{ - }_{3} \) leaching due to these changes (a and b above) in both plant and microbial functioning, (d) reduced sensitivity of vegetation to N additions in areas with high historical N deposition, (e) delayed changes in soil C:N changes due to increased net primary productivity and reduced decomposition of soil organic matter. Some suggestions of early indicators of N saturation are suggested (occurrence of mosses; \({\text{NH}}^{ + }_{4} :{\text{NO}}^{ - }_{3} \) ratio in surface soils) which indicate either a shift in ecosystem function and/or structure.

Nitrogen saturation of terrestrial ecosystems: some recent findings and their implications for our conceptual framework

The interactions between plant growth, vegetation structure and soil processes in semi-natural acidic and calcareous grasslands receiving long-term inputs of simulated pollutant nitrogen deposition

The impact of reduced light conditions as an indirect effect of nitrogen (N) deposition was determined on three mosses in a montane ecosystem, where sedge and grass cover increase due to N enrichment. Additionally, in the greenhouse we established the importance of low light to moss growth as an indirect N deposition effect relative to the direct toxic effects of N. The amount of light reaching the moss layer was strongly and negatively related to graminoid abundance. Mosses showed differing sensitivities to reduced light in the field. Racomitrium lanuginosum biomass was found to be highest under high-light conditions, Polytrichum alpinum at intermediate light levels, whilst that of Dicranum fuscescens was unrelated to light availability. Moreover, Racomitrium biomass decreased with increasing amounts of graminoid litter, whereas the other species were little affected. All three mosses responded differently to the combination of elevated N (20 vs 10 kg N ha−1 year−1) and reduced light (60 and 80% reduction) in the greenhouse. Racomitrium growth was strongly influenced by both light reduction and elevated N, in combination reducing shoot biomass up to 76%. There was a tendency for Dicranum growth to be modestly reduced by elevated N when shaded, causing up to 19% growth reduction. Polytrichum growth was not influenced by elevated N but was reduced up to 40% by shading. We conclude that competition for light, induced by vascular plants, can strongly influence moss performance even in unproductive low biomass ecosystems. The effects of reduced light arising from N pollution can be as important to mosses as direct toxicity from N deposition. Yet, different sensitivities of mosses to both toxic and shading effects of elevated N prevent generalisation and can lead to competitive species replacement within moss communities. This study demonstrates the importance of understanding moss-vascular plant interactions to allow interpretation and prediction of ecosystem responses to anthropogenic drivers such as atmospheric N deposition or climate change.

/pdf/mosses-and-the-struggle-for-light-in-a-nitrogen-polluted-5eb0gpjbx9.pdf

Mosses and the struggle for light in a nitrogen-polluted world.

Nitrogen content, 15N natural abundance and biomass of the two pleurocarpous mosses Pleurozium schreberi (Brid.) Mitt. and Scleropodium purum (Hedw.) Limpr. in relation to atmospheric nitrogen deposition

Empirical nitrogen critical loads for natural and semi-natural ecosystems : 2002 update

Regular applications of NH4NO3 (3.5–14 g N m−2 yr−l) and (NH4)2SO4 (14 g N m−2 yr−l) to areas of acidic grassland in the Derbyshire Peak District over a period of six years have resulted in marked changes in the abundance of the bryophyte species present on the site. A dose-related reduction in bryophyte cover, significant at all levels of nitrogen addition, was obtained after only one year of applications and this effect has been maintained over a further five years of treatment.(NH4)2SO4 additions at the same rate as the highest NH4NO3 input (14 g N m−2 yr−1) produced greater reductions in cover with losses of 80–95% compared with 45–55% for the 14 g NH4NO3 treatment. Soil pH measurements taken from cores collected in December 1994 showed a small reduction in the pH of the (NH4)2SO4 treated plots (4.03 compared with 4.41 for the controls), whereas the NH4NO3 treatments were unaffected.The mean stem density of the dominant bryophyte species Rhytidiadelphus squarrosus was significantly reduced at ...

The effect of long-term nitrogen additions on the bryophyte cover of upland acidic grasslands

Medical students employ various study strategies to master large amounts of information during their medical education. Digital flashcards are an interactive, self-directed study stool that may improve knowledge retention by combining the principles of active recall and spaced-repetition. They may be studied during and beyond undergraduate medical education. However, making flashcards can be an onerous task. In this article, we describe twelve tips on how to establish and maintain a collaborative digital flashcard project based on the undergraduate medical curriculum.

Twelve tips for medical students to establish a collaborative flashcard project.

Background
Discharge communication is an important aspect of high-quality emergency care. This study addresses the gap in knowledge on how to describe discharge communication in a paediatric emergency department (ED).

Objective
The objective of this feasibility study was to develop and test a coding scheme to characterize discharge communication between health-care providers (HCPs) and caregivers who visit the ED with their children.

Design
The Pediatric Emergency Discharge Interaction Coding Scheme (PEDICS) and coding manual were developed following a review of the literature and an iterative refinement process involving HCP observations, inter-rater assessments and team consensus.

Setting and participants
The coding scheme was pilot-tested through observations of HCPs across a range of shifts in one urban paediatric ED.

Main variables studied
Overall, 329 patient observations were carried out across 50 observational shifts. Inter-rater reliability was evaluated in 16% of the observations. The final version of the PEDICS contained 41 communication elements.

Results
Kappa scores were greater than .60 for the majority of communication elements. The most frequently observed communication elements were under the Introduction node and the least frequently observed were under the Social Concerns node. HCPs initiated the majority of the communication.

Conclusion
Pediatric Emergency Discharge Interaction Coding Scheme addresses an important gap in the discharge communication literature. The tool is useful for mapping patterns of discharge communication between HCPs and caregivers. Results from our pilot test identified deficits in specific areas of discharge communication that could impact adherence to discharge instructions. The PEDICS would benefit from further testing with a different sample of HCPs.

https://www.onlinelibrary.wiley.com/doi/pdf/10.1111/hex.12512

Development and feasibility testing of the Pediatric Emergency Discharge Interaction Coding Scheme.

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

Our objective was to review and synthesize all organizational and professional intervention strategies in emergency practice settings that focus on improving the health outcomes of adults and children with asthma.

Interventions to improve management and health outcomes for children and adults with asthma who present to the emergency department

Among other things, a fluid dispenser has an indicium that indicates to individuals in the vicinity whether it has been used within a predetermined length of time. Overlays to fluid dispensers to add this functionality are also described, as well as other fluid dispensers equipped with indicia used as a reminder.

Alexandra Taylor

Papers

The effect of long-term nitrogen additions on the bryophyte cover of upland acidic grasslands

Twelve tips for medical students to establish a collaborative flashcard project.

Development and feasibility testing of the Pediatric Emergency Discharge Interaction Coding Scheme.

Interventions to improve management and health outcomes for children and adults with asthma who present to the emergency department

Hygiene enhancing dispenser