9 research outputs found
The biogeochemical impact of glacial meltwater from Southwest Greenland
Biogeochemical cycling in high-latitude regions has a disproportionate impact on global nutrient budgets. Here, we introduce a holistic, multi-disciplinary framework for elucidating the influence of glacial meltwaters, shelf currents, and biological production on biogeochemical cycling in high-latitude continental margins, with a focus on the silica cycle. Our findings highlight the impact of significant glacial discharge on nutrient supply to shelf and slope waters, as well as surface and benthic production in these regions, over a range of timescales from days to thousands of years. Whilst biological uptake in fjords and strong diatom activity in coastal waters maintains low dissolved silicon concentrations in surface waters, we find important but spatially heterogeneous additions of particulates into the system, which are transported rapidly away from the shore. We expect the glacially-derived particles â together with biogenic silica tests â to be cycled rapidly through shallow sediments, resulting in a strong benthic flux of dissolved silicon. Entrainment of this benthic silicon into boundary currents may supply an important source of this key nutrient into the Labrador Sea, and is also likely to recirculate back into the deep fjords inshore. This study illustrates how geochemical and oceanographic analyses can be used together to probe further into modern nutrient cycling in this region, as well as the palaeoclimatological approaches to investigating changes in glacial meltwater discharge through time, especially during periods of rapid climatic change in the Late Quaternary
Diagnosing mucopolysaccharidosis IVA
Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is an autosomal recessive lysosomal storage disorder resulting from a deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS) activity. Diagnosis can be challenging and requires agreement of clinical, radiographic, and laboratory findings. A group of biochemical genetics laboratory directors and clinicians involved in the diagnosis of MPS IVA, convened by BioMarin Pharmaceutical Inc., met to develop recommendations for diagnosis. The following conclusions were reached. Due to the wide variation and subtleties of radiographic findings, imaging of multiple body regions is recommended. Urinary glycosaminoglycan analysis is particularly problematic for MPS IVA and it is strongly recommended to proceed to enzyme activity testing even if urine appears normal when there is clinical suspicion of MPS IVA. Enzyme activity testing of GALNS is essential in diagnosing MPS IVA. Additional analyses to confirm sample integrity and rule out MPS IVB, multiple sulfatase deficiency, and mucolipidoses types II/III are critical as part of enzyme activity testing. Leukocytes or cultured dermal fibroblasts are strongly recommended for enzyme activity testing to confirm screening results. Molecular testing may also be used to confirm the diagnosis in many patients. However, two known or probable causative mutations may not be identified in all cases of MPS IVA. A diagnostic testing algorithm is presented which attempts to streamline this complex testing process
ICONE18-30343 Enhanced CANDU 6: An Upgraded Reactor Product with Optimal Fuel Cycle Capability
ABSTRACT Atomic Energy of Canada Limited (AECL) has two CAND
Context Sensitive Solutions for Construction and Maintenance
The objective of this research was to conduct a survey to assess the state of practice related to state highway agencies (SHAs) implementing context sensitive solutions including its application in Construction and Maintenance and to prepare a workshop enabling SHA officials to adopt practices promoting context sensitivity beyond Planning and Design.
Deliverables from the study efforts include a survey summary of context sensitive solutions and workshop materials/presentation suitable for use in training a wide range of SHA personnel working in Construction and Maintenance
ICONE10 -22718 NEXT GENERATION CANDU: CONCEPTUAL DESIGN FOR A SHORT CONSTRUCTION SCHEDULE
ABSTRACT Atomic Energy of Canada Ltd. (AECL) has very successful experience in implementing new construction methods at the Qinshan (Phase III) twin unit CANDU 6 plant in China. This paper examines the construction method that must be implemented during the conceptual design phase of a project if short construction schedules are to be met. A project schedule of 48 months has been developed for the nth unit of NG (Next Generation) CANDU with a 42 month construction period from 1st Concrete to In-Service. An overall construction strategy has been developed involving paralleling project activities that are normally conducted in series. Many parts of the plant will be fabricated as modules and be installed using heavy lift cranes. The Reactor Building (RB), being on the critical path, has been the focus of considerable assessment, looking at alternative ways of applying the construction strategy to this building. A construction method has been chosen which will result in excess of 80% of internal work being completed as modules or as very streamlined traditional construction. This method is being further evaluated as the detailed layout proceeds. Other areas of the plant have been integrated into the schedule and new construction methods are being applied to these so that further modularization and even greater paralleling of activities will be achieved. It is concluded that the optimized construction method is a requirement, which must be implemented through all phases of design to make a 42 month construction schedule a reality. If the construction methods are appropriately chosen, the schedule reductions achieved will make nuclear more competitive
Context Sensitive Design â Thinking Beyond the Pavement: Documentation of Workshop Development and Training
This report documents the development and presentation of the workshop titled âThinking Beyond the Pavement â A Workshop on Context Sensitive Designâ. Work began on the workshop development in 1998 after the Kentucky Transportation Cabinet was selected as one of the pilot states to implement a training program for context sensitive design. The Kentucky Transportation Center at the University of Kentucky was selected to develop and deliver the training to state personnel and consultants who were commonly involved with project development. The training course was comprised of the following four modules: Facilitated Communication and Public Involvement, Environmental Issues, Liability Issues, and Design Guidelines, Safety, and Aesthetics.
A case study was prepared for use with the training modules in order to simulate the project development process and promote participant interaction. Through May 2004, there were 46 presentations of the workshop with 1,693 participants