Coupled nitrification and N2 gas production as a cryptic process in oxic riverbeds.

The coupling between nitrification and N2 gas production to recycle ammonia back to the atmosphere is a key step in the nitrogen cycle that has been researched widely. An assumption for such research is that the products of nitrification (nitrite or nitrate) mix freely in the environment before reduction to N2 gas. Here we show, in oxic riverbeds, that the pattern of N2 gas production from ammonia deviates by ~3- to 16-fold from that predicted for denitrification or anammox involving nitrite or nitrate as free porewater intermediates. Rather, the patterns match that for a coupling through a cryptic pool, isolated from the porewater. A cryptic pool challenges our understanding of a key step in the nitrogen cycle and masks our ability to distinguish between sources of N2 gas that 20 years' research has sought to identify. Our reasoning suggests a new pathway or a new type of coupling between known pathways in the nitrogen cycle

Spatial separation of anaerobic ammonium oxidation and nitrite-dependent anaerobic methane oxidation in permeable riverbeds.

Anaerobic ammonium oxidation (anammox) and nitrite-dependent anaerobic methane oxidation (n-damo) play important roles in nitrogen and carbon cycling in fresh waters but we do not know how these two processes compete for their common electron acceptor, nitrite. Here, we investigated the spatial distribution of anammox and n-damo across a range of permeable riverbed sediments. Anammox activity and gene abundance were detected in both gravel and sandy riverbeds and showed a simple, common vertical distribution pattern, while the patterns in n-damo were more complex and n-damo activity was confined to the more reduced, sandy riverbeds. Anammox was most active in surficial sediment (0-2cm), coincident with a peak in hzsA gene abundance and nitrite. In contrast, n-damo activity peaked deeper down (4-8cm) in the sandy riverbeds, coincident with a peak in n-damo 16S rRNA gene abundance and higher methane concentration. Pore water nitrite, methane and oxygen were key factors influencing the distribution of these two processes in permeable riverbeds. Furthermore, both anammox- and n-damo- activity were positively correlated with denitrification activity, suggesting a role for denitrification in supplying both processes with nitrite. Our data reveal spatial separation between anammox and n-damo in permeable riverbed sediments that potentially avoids them competing for nitrite. This article is protected by copyright. All rights reserved

Space shuttle abort separation pressure investigation. Volume 2, Part B: Orbiter data at Mach 5

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Roadblocks and Enablers for Teacher Engagement in Professional Development Opportunities Aimed at Supporting Trauma-informed Classroom Pedagogical Practice

This paper is based on a research approach that aims to explore and explain the roadblocks and enablers for mainstream classroom teachers engaging in professional development and training focused on trauma informed pedagogical practices.. Teachers seeking resources that promote discrete behavioural and cognitive skills in the social emotional developmental domain can easily access advocacy, policy articles and resource materials that are in the form of guides, toolkits, and programs. Notwithstanding this, a second focus area is the relational approach whereby the main tenet is children’s social, emotional, and cognitive development is dependent on the relational context in which they spend their time. It is an area that emphasises the interpersonal skills of adults rather than focusing on the knowledge and behavioural skills of the child. A considerable body of research exists that supports the relational approach of trauma informed practice to mitigate the effects of risk factors in the lives of children with developmental trauma. The aim of this paper is to assess and discuss the methodology, rationale, and results for this research through examining the qualitative research process undertaken with a group of mainstream primary school teachers. This paper will examine the outcomes of the teacher interviews that highlight the roadblocks and enablers for teachers engaging in education and training to enhance their skills and knowledge on being trauma informed in their teaching practices. These results have significant implications for future framework development in school settings

Family preferences for home or hospital care at diagnosis for children with diabetes in the DECIDE study.

This is the final version of the article. Available from Wiley via the DOI in this record.AIMS: A diagnosis of Type 1 diabetes in childhood can be a difficult life event for children and families. For children who are not severely ill, initial home rather than hospital-based care at diagnosis is an option although there is little research on which is preferable. Practice varies widely, with long hospital stays in some countries and predominantly home-based care in others. This article reports on the comparative acceptability and experience of children with Type 1 diabetes and their parents taking part in the DECIDE study evaluating outcomes of home or hospital-based treatment from diagnosis in the UK. METHODS: Semi-structured interviews with 11 (pairs of) parents and seven children were conducted between 15 and 20 months post diagnosis. Interviewees were asked about adaptation to, management and impact of the diabetes diagnosis, and their experience of initial post-diagnosis treatment. RESULTS: There were no differences between trial arms in adaptation to, management of or impact of diabetes. Most interviewees wanted to be randomized to the 'home' arm initially but expressed a retrospective preference for whichever trial arm they had been in, and cited benefits relating to learning about diabetes management. CONCLUSIONS: The setting for early treatment did not appear to have a differential impact on families in the long term. However, the data presented here describe different experiences of early treatment settings from the perspective of children and their families, and factors that influenced how families felt initially about treatment setting. Further research could investigate the short-term benefits of both settings.National Institute for Social Care and Health Research Clinical Research Centr

A new mechanism for exchange processes observed in the compounds [M(η-C_5H_5)_2(exo-η-RCH = CH_2)H], M = Nb and Ta

Dynamic n.m.r. studies of the exchange processes in the complexes [M(η-C_5H_5)(exo-η-RCH=CH_2)H], M = Nb, Ta, lead to the proposal of a new mechanism involving intermediates with agostic bonding

Space shuttle abort separation pressure investigation. Volume 6: Orbiter data at Mach 2

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Investigation of the McDonnell-Douglas orbiter and booster shuttle models in proximity at Mach numbers 2.0 to 6.0. Volume 7: Proximity data at Mach 4 and 6, interference free and launch vehicle data

Aerodynamic data obtained from a space shuttle abort stage separation wind tunnel test are presented. The .00556 scale models of the orbiter and booster configuration were tested in close proximity using dual balances during the time period of April 21 to April 27 1971. Data were obtained for both booster and orbiter over an angle of attack range from -10 to 10 deg for zero degree sideslip angle. The models were tested at several relative incidence angles and separation distances and power conditions. Plug nozzles utilizing air were used to simulate booster and orbiter plumes at various altitudes along a nominal ascent trajectory. Powered conditions were 100, 50, 25 and 0 percent of full power for the orbiter and 100, 50 and 0 percent of full power for the booster. Pitch control effectiveness data were obtained for both booster and orbiter with power on and off. In addition, launch vehicle data with and without booster power were obtained utilizing a single balance in the booster model. Data were also obtained with the booster canard off in close proximity and for the launch configuration

Space shuttle abort separation pressure investigation. Volume 1, Part A: Booster data at Mach 5

Pressure data obtained from a joint Langley Research Center (LaRC)/Marshall Space Flight Center (MSFC) Space Shuttle about stage separation wind tunnel test are presented. The .00556 scale models of the McDonnell-Douglas orbiter and booster configurations were tested in proximity in Tunnel A of the Von Karman Facility (VKF), Arnold Engineering Development Center (AEDC). Mach numbers were 5.0, 3.0, and 2.0 and nominal Reynolds numbers were 1.09, 1.60, and 1.74 million per foot, respectively. Pressure data were obtained for the booster upper surface and orbiter lower surface at angles of attack of -10 deg, -5, 0, 5, and 10 deg for zero degrees sideslip. The models were tested at incidence angles of 0 and 5 deg for several separation distances and power conditions. Plug nozzles utilizing air were used to simulate booster and orbiter plumes at various altitudes along a nominal ascent trajectory. Powered conditions were 100, 50, and 0 percent of full power for the orbiter and 100, 50 and 0 percent of full power for the booster. Data were also obtained with the booster canard off in close proximity

Space shuttle abort separation pressure investigation. Volume 1, Part B: Booster data at Mach 5

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