Trace Metal-Particle Water Interactions in the Western North Sea

The distribution of trace metals (Fe, Mn, Cu, Cd and Pb) has been determined in dissolved and particulate phases, along with relevant hydrographic parameters, from the nearshore coastal zone of the western North Sea (between 52ON and 56ON) during four Land Ocean Interaction Study (LOIS) surveys covering the seasonal cycle (autumn 1994 to summer 1995) The behaviour of the redox-sensitive metals, Fep and Mnp in the western North Sea were strongly correlated (r>0 44 for all seasons, P<0 05) in all surveys and exhibited maximum concentrations in winter (16 mg g -1 and 700 ug g-1 respectively) which progressively decreased throughout the year Distinct seasonal variations were also observed for particulate Cu, Cd and Pb For example, enhanced concentrations of Cup (36 ± 39 ug g-1) and Cdp (0.36 ± 0.42 ug g -1) in the Humber coastal zone during summer were attributed to preferential particulate organic/biogenic-metal interactions. In contrast enhanced, though diffuse, atmospheric inputs of Pb from continental winds were considered to have contributed to the elevated Pbp concentrations (82 ± 27 ug g -1) observed offshore during winter Results from radiotracer incubation experiments suggest that biological activity makes a significant contribution to the removal of dissolved Mn and Cd to the particulate phase. However, a phase lag of two to three months between maximum primary productivity and maximum particulate metal adsorption (KD=2 X 104 & 5 x 102 for Mn and Cd respectively) indicates a decoupling from the spring plankton bloom In general metal distributions in the Humber coastal zone were significantly influenced by freshwater discharge, tidal regime at the mouth of the estuary and prevailing wind conditions Total trace metal fluxes across the mouth of the Humber Estuary were highest during spring (311, 8 96 & 1045 kg day-1, for Cu, Cd and Pb respectively) and lowest during summer (25 7, 1 .12 & 33 4 kg day-1, for Cu, Cd and Pb respectively) They were dominated by variations in freshwater outflow and the tidal range during sampling On an annual basis comparison to estuarine inputs (rivers, industry and sewage sources) suggested retention of Cu (25%) and Cd (56%) Estimates of partitioning (KD) were derived from the dissolved and particulate data for Cu, Cd and Pb over the seasonal cycle Copper was dominated by the particulate phase (73-80%) in all seasons but summer, whilst Cd showed particulate phase dominance (54-70%) in autumn and winter only The Pb distributions were dominated by the particulate phase (94-99%) independent of season Trace metal settling velocities implied that the Humber Plume was acting as a sink for Cu, Cd and Pb in winter and spring However settling velocities calculated for Cd and Pb (flood tide) in summer were similar to background suspended particulate matter (SPM) suggesting long range transport with the residual circulation. Modelling of Pb isotopic ratios in the Humber Plume suggested that on average 32-39% of the extracted Pbp originated from anthropogenic sources The data from this study has given unique information concerning the concurrent seasonal distributions of particulate trace metals in the western North Sea and have yielded new insights into mechanisms affecting trace metal cycling and transport, essential in the development and refinement of coupled hydrodynamic-geochemical models.Plymouth Marine Laborator

Seasonal changes in microbial dissolved organic sulfur transformations in coastal waters

The marine trace gas dimethylsulfide (DMS) is the single most important biogenic source of atmospheric sulfur, accounting for up to 80% of global biogenic sulfur emissions. Approximately 300 million tons of DMS are produced annually, but the majority is degraded by microbes in seawater. The DMS precursor dimethylsulfoniopropionate (DMSP) and oxidation product dimethylsulphoxide (DMSO) are also important organic sulfur reservoirs. However, the marine sinks of dissolved DMSO remain unknown. We used a novel combination of stable and radiotracers to determine seasonal changes in multiple dissolved organic sulfur transformation rates to ascertain whether microbial uptake of dissolved DMSO was a significant loss pathway. Surface concentrations of DMS ranged from 0.5 to 17.0 nM with biological consumption rates between 2.4 and 40.8 nM·d−1. DMS produced from the reduction of DMSO was not a significant process. Surface concentrations of total DMSO ranged from 2.3 to 102 nM with biological consumption of dissolved DMSO between 2.9 and 111 nM·d−1. Comparisons between 14C2-DMSO assimilation and dissimilation rates suggest that the majority of dissolved DMSO was respired (>94%). Radiotracer microbial consumption rates suggest that dissimilation of dissolved DMSO to CO2 can be a significant loss pathway in coastal waters, illustrating the significance of bacteria in controlling organic sulfur seawater concentrations

Ruthenium-106 Plaque Therapy for Diffuse Choroidal Hemangioma in Sturge-Weber Syndrome

Diffuse choroidal hemangiomas associated with Sturge-Weber syndrome (SWS) are classically treated with external beam radiotherapy (EBR), but there are a few reports usually of single cases indicating the usefulness of plaque therapy. We present our observations on two cases of diffuse choroidal hemangiomas with exudative retinal detachment associated with SWS treated with Ruthenium-106 plaque therapy. Outcomes included best-corrected visual acuity (BCVA) and regression in tumor thickness measured by ultrasonography. The initial BCVA of the affected eyes was counting fingers at 1 meter and light projection. Pretreatment tumors thickness was 3.5 mm and 4.7 mm. In a follow-up period of 18–24 months, significant reduction in thickness of choroidal hemangiomas up to 1.2 mm and 1.4 mm with prompt resolution of exudative retinal detachment was observed. BCVA achieved 20/200 and 20/400, respectively. The findings in this paper indicate that Ruthenium-106 plaque therapy is effective in treatment of diffuse choroidal hemangiomas associated with SWS

POTENTIAL INFLUENCE OF FOOTWEAR ON ANKLE INVERSION INJURY RISK DURING LATERAL JUMPS IN OLDER ADULTS

The purpose of this study was to explore the effect of footwear on the ankle inversion and plantar pressure experienced by older females performing change of direction tasks. Eight older female tennis players performed five lateral side jumps and five 180° turns in a running shoe and tennis shoe. Time of peak plantar pressure and peak ankle inversion angle were recorded. Individual differences revealed reduced magnitude and duration of rearfoot loading and increased forefoot loading of two participants in the running shoe compared to the tennis shoe when performing the lateral side jumps. Greater peak inversion angle was also recorded in the running shoe compared to the tennis shoe for these participants. While the cushioning properties of running shoes may be appealing for some older tennis players, wearing running shoes during tennis may increase the risk of incurring an ankle sprain

Forecasting infrastructure resilience to climate change

Resilience of the UK transport infrastructure network can be expressed as the imbalance between the physical condition of the network and the transport demands the network experiences. Forecasting changes of resilience in the long term (e.g. the 2050s) requires a structured, multi-disciplinary approach. The Engineering and Physical Sciences Research Council funded Futurenet project developed a model architecture to formalise such an approach and this paper addresses one component: the assessment of the influence of physical processes on asset condition. This requires the development of new, integrated physical-based models that respond to detailed inputs of forecast weather events (e.g. UK Climate Projections 2009). The results are plotted onto the infrastructure network for visualisation. Subsequent combination with user demand will then enable determination of network resilience at a range of spatial scales. The project has highlighted the need for better datasets, more sophisticated physical-based models and further analyses of complex feedbacks and interactions between physical processes and also with user behaviour

The footwear needs and preferences of adults over 55 years of age participating in court sports

Court sports like tennis are popular with older adults and important for maintaining physical and mental health. Footwear can influence player experience and injury risk in sports. Previous preliminary work using interviews and focus groups identified key themes regarding comfort (including cushioning), functionality (including a wide width) and choice (including appearance) that are important aspects of footwear for older adults. The purpose of this study was to explore the attitudes towards athletic footwear and the footwear features considered important in older adults playing court sports across the population. An online survey was conducted of older adults in the UK/Ireland who participated in court sports at least once a week. Questionnaire items included descriptive information on age, gender, playing level and sport played and Likert item questions regarding attitudes and important footwear features. Using a mixed methods approach, percentage agreement and importance was combined with qualitative comments. Comfort, appropriate grip, good cushioning and overall support were all important for over 95% of respondents. Width, durability and reducing the likelihood of injury were also important to over 80% of respondents. Around 20% of female participants agreed they had difficulty in purchasing sports shoes with their desired aesthetics compared to around 10% of male participants. Some women reported needing to buy men’s shoes for adequate width, while 12% of respondents reported wearing non-specific footwear like running shoes, often for extra cushioning or to avoid foot pain, which could put them at greater risk of injuries such as ankle sprains. It would appear the athletic footwear industry in the UK/Ireland could do more to improve player comfort and safety of older adults in court sports