Hexactinellida (Porifera) from the Drake Passage (Southern Ocean) with a description of three new species

Goodwin, Claire E., Berman, Jade, Janussen, Dorte, Göcke, Christian, Hendry, Katharine R. (2016): Hexactinellida (Porifera) from the Drake Passage (Southern Ocean) with a description of three new species. Zootaxa 4126 (2): 207-220, DOI: http://doi.org/10.11646/zootaxa.4126.2.

SiCLING Ny-Ålesund Fieldwork Report. 15th - 29th July 2024

The polar regions are experiencing the most rapid climate change observed on Earth. Marine ecosystems are already responding to – and amplifying – environmental change, with important implications for carbon burial and important natural resources such as fisheries. One important type of microalgae, which form the basis of these polar ecosystems and an important conduit for carbon flow from the surface to the seafloor, are diatoms. Diatoms build their microscopic shells from silica, and so dissolved silicon (DSi) is a critical nutrient for their growth. We need a better understanding of how climate-sensitive processes within polar environments impact silicon cycling, and their consequences for regional and global systems. SiCLING will explore novel hypotheses linking silicon and metal cycling within glacial sediments in Arctic and Antarctic fjords, resulting in a step-change in our understanding of silicon mobility and bioavailability in fjords, high-latitude nutrient balance, and the flow of nutrients into the polar coastal ocean and beyond. Our recent work has shown that glaciers are a substantial source of both dissolved silicon (DSi) and reactive particles of silica, termed ASi. However, the processes by which DSi and ASi escape glaciated fjords are under scrutiny; these processes have profound implications for the supply of DSi to coastal and open ocean ecosystems in the polar regions, and ultimately how this system will respond and change in the future. We have shown that, whilst the coastal shelf waters are very low in DSi, the interaction between shelf sediments and bottom waters is an important conduit for this critical nutrient into the overlying water column. Further inland, nearer the glaciers, our new data indicate that the DSi within the sediments themselves have a unique geochemical and isotopic fingerprint – and this fingerprint appears to be the same wherever we look: in the Arctic, Antarctic and in mid-latitude glaciated mountain regions like Chilean Patagonia. Given the extent and the nature of this signal, we propose that there is an important and ubiquitous – but yet unknown – mechanism that controls the release of DSi into fjords and then into the coastal ocean, acting as an effective trap of this important nutrient. We propose that this mechanism is likely not entirely biological, but relates to the interactions between silicon and another important element for life: iron. Iron is also released in large quantities from glacial weathering, and the iron released is highly reactive with the capability of mopping up significant quantities of DSi. This mechanism is likely to be climate sensitive (because of the glacial meltwater source and temperature/salinity effects), and understanding the underlying processes will be crucial for predicting future change especially in the context of accelerating polar warming and land-ice melting. SiCLING will be the first project to focus specifically on these previously overlooked links between dynamic silicon and iron cycling in the polar regions, incorporating cutting-edge analysis of field and laboratory samples and advanced geochemical modelling. The Ny-Ålesund component of this project centres around the Arctic case study investigating the particle-water interactions in Kongsfjorden

More capable others? Education Studies undergraduates as near-peer mentors for year 12 students

This research focused on the benefits and challenges for second year Education Studies undergraduate students acting as near-peer mentors for year 12 students (aged 16-17). Near-peer mentoring often involves postgraduate students working with new undergraduates and is more common during Science Technology Engineering and Maths (STEM) programmes. There is little research available, outside of STEM, about how near-peer mentors might influence the aspirations of students to access HE, or of the impact on undergraduate mentors themselves.   The student near-peer mentors were part of the Research Higher project in an area of England with unexplained low participation rates in HE. The project involved circa 200 students from local schools in a programme of weekly events where they designed and conducted their own research. Second year Education Studies undergraduate students supported two cohorts of year 12 students during their on-campus seminar activities. The findings draw on thematic analysis of undergraduate student interviews at the end of the project. They indicate that near-peer mentoring has unexpected benefits for undergraduate Education Studies students including meta-cognition about their own learning and confidence in working with older students. Recommendations for future near-peer mentoring programmes are proposed based on student feedback

Scotland’s Housing Expo 2010

Scotland’s first Housing Expo took place in Inverness in August 2010, attracting over 33,000 visitors from all parts of Scotland, the rest of the UK and abroad. There is considerable enthusiasm in the house design and construction industry for more projects of this nature to further the objective of raising public interest in well-designed, sustainable housing and communities. Ministers agreed in October 2010 to commission a full review and evaluation of the achievements of the Expo as well as highlighting areas for improvement before any encouragement is given for more projects of this nature

The isotope composition of inorganic Germanium in seawater and deep sea sponges

Although dissolved concentrations of germanium (Ge) and silicon (Si) in modern seawater are tightly correlated, uncertainties still exist in the modern marine Ge cycle. Germanium stable isotope systematics in marine systems should provide additional constraints on marine Ge sources and sinks, however the low concentration of Ge in seawater presents an analytical challenge for isotopic measurement. Here, we present a new method of pre-concentration of inorganic Ge from seawater which was applied to measure three Ge isotope profiles in the Southern Ocean and deep seawater from the Atlantic and Pacific Oceans. Germanium isotopic measurements were performed on Ge amounts as low as 2.6 ng using a double-spike approach and a hydride generation system coupled to a MC-ICP-MS. Germanium was co-precipitated with iron hydroxide and then purified through anion-exchange chromatography. Results for the deep (i.e. > 1000 m depth) Pacific Ocean off Hawaii (nearby Loihi Seamount) and the deep Atlantic off Bermuda (BATS station) showed nearly identical δ74/70Ge values at 3.19 ± 0.31 ‰ (2SD, n = 9) and 2.93 ± 0.10 ‰ (2SD, n = 2), respectively. Vertical distributions of Ge concentration and isotope composition in the deep Southern Ocean for water depth > 1300 m yielded an average δ74/70Ge = 3.13 ± 0.25 ‰ (2SD, n = 14) and Ge/Si = 0.80 ± 0.09 μmol/mol (2SD, n = 12). Significant variations in δ74/70Ge, from 2.62 to 3.71 ‰, were measured in the first 1000 m in one station of the Southern Ocean near Sars Seamount in the Drake Passage, with the heaviest values measured in surface waters. Isotope fractionation by diatoms during opal biomineralization may explain the enrichment in heavy isotopes for both Ge and Si in surface seawater. However, examination of both oceanographic parameters and δ74/70Ge values suggest also that water mass mixing and potential contribution of shelf-derived Ge also could contribute to the variations. Combining these results with new Ge isotope data for deep-sea sponges sampled nearby allowed us to determine a Ge isotope fractionation factor of -0.87 ± 0.37 ‰ (2SD, n = 12) during Ge uptake by sponges. Although Ge has long been considered as a geochemical twin of Si, this work underpins fundamental differences in their isotopic behaviors both during biomineralization processes and in their oceanic distributions. This suggests that combined with Si isotopes, Ge isotopes hold significant promise as a complementary proxy for delineating biological versus source effects in the evolution of the marine silicon cycle through time

Silicon isotopes of deep-sea sponges:new insights into biomineralisation and skeletal structure

The silicon isotopic composition (δ30Si) of deep sea sponges’ skeletal element – spicules – reflects the silicic acid (DSi) concentration of their surrounding water and can be used as natural archives of bottom water nutrients. In order to reconstruct the past silica cycle robustly, it is essential to better constrain the mechanisms of biosilicification, which are not yet well understood. Here, we show that the apparent isotopic fractionation (δ30Si) during spicule formation in deep sea sponges from the equatorial Atlantic ranges from −6.74 ‰ to −1.50 ‰ in relatively low DSi concentrations (15 to 35 μM). The wide range in isotopic composition highlights the potential difference in silicification mechanism between the two major classes, Demospongiae and Hexactinellida. We find the anomalies in the isotopic fractionation correlate with skeletal morphology, whereby fused framework structures, characterised by secondary silicification, exhibit extremely light δ30Si signatures compared with previous studies. Our results provide insight into the processes involved during silica deposition and indicate that reliable reconstructions of past DSi can only be obtained using silicon isotope ratios derived from sponges with certain spicule types.ACKNOWLEDGEMENTS. We acknowledge the science team and the crew of JC094 and Laura Robinson for cruise organisation. We would also like to thank Paul Curnow for constructive com- ments, Stuart Kearns for his SEM training and assistance, and Maria López-Acosta for her help. Finally, the funding from the Royal Society (grant code RG130386) and from the European Research Council is acknowledged. Joana R. Xavier received support from the European Union's Horizon 2020 research and innovation program through the SponGES project (grant agreement no. 679849). SAMPLE AVAILABILITY. Samples and sample images are available at the University of Bristol; for further detail contact Katharine R. Hendry, email address: [email protected]

Where do UK clinicians find information at the point of care? A pragmatic, exploratory study

Funding: CSO Fellowship (MM).Aim To describe where clinical information is contemporarily and commonly found in UK primary care, what is favoured by clinicians, and whether this is (1) publicly funded (2) has commercial potential conflicts of interest. Design and setting A mixed methods study, consisting of (1) site visits to general practices in Scotland, (2) online questionnaire, focused on UK general practice (3) analysis of materials cited by professionals. Methods Data about sources of clinical information used was obtained verbally, visually and via search histories on computers from visits. This was used to inform a questionnaire in which primary care clinicians in the four nations of the UK were invited to participate. This obtained data about the information sources used and preferred by clinicians. This information was searched for data about funding and conflicts of interest. Results Over 2022, four practices were visited. 337 clinicians, 280 of whom were general practitioners completed an online questionnaire. 136 different resources were identified. These were mainly websites but sources of information included colleagues, either in practice or through online networks, apps, local guidelines, health charities, and learning resources aimed at GPs. Of these, 70 were not publicly funded, and were a mixture of membership organisations, charities, or sponsored venues. Conclusions Primary care clinicians obtain information for themselves and patients from a wide variety of sources. Funding is from a variety of sources and some contain advertising and/or sponsorship, risking commercial bias. Protocol Pre-published at https://osf.io/wrzqk.Peer reviewe

Long-Term Outcomes in IgA Nephropathy

BACKGROUND: IgA nephropathy can progress to kidney failure, and risk assessment soon after diagnosis has advantages both for clinical management and the development of new therapeutics. We present relationships among proteinuria, eGFR slope and lifetime risks for kidney failure.METHODS: The IgA nephropathy cohort (2,299 adults, 140 children) of the UK National Registry of Rare Kidney Diseases (RaDaR) was analyzed. Patients enrolled had a biopsy-proven diagnosis of IgA nephropathy, plus proteinuria &gt;0.5 g/day or eGFR &lt;60 mL/min/1.73m 2 . Incident and prevalent populations were studied as well as a population representative of a typical phase 3 clinical trial cohort. Analyses of kidney survival were conducted using Kaplan-Meier and Cox regression. eGFR slope was estimated using linear mixed models with random intercept and slope.RESULTS: Median (Q1, Q3) follow-up was 5.9 (3.0, 10.5) years; 50% of patients reached kidney failure or died in the study period. Median (95% CI) kidney survival was 11.4 (10.5, 12.5) years; mean age at kidney failure/death was 48 years, and most patients progressed to kidney failure within 10-15 years. Based on eGFR and age at diagnosis, almost all patients are at risk of progression to kidney failure within their expected lifetime unless a rate of eGFR loss ≤1 ml/min/1.73m 2 /year can be maintained. Time-averaged proteinuria was significantly associated with worse kidney survival and more rapid eGFR loss in incident, prevalent, and "clinical trial" populations. 30% of patients with time-averaged proteinuria of 0.44 to &lt;0.88 g/g and approximately 20% of patients with time-averaged proteinuria &lt;0.44 g/g developed kidney failure within 10 years. In the "clinical trial" population each 10% decrease in time-averaged proteinuria from baseline was associated with a hazard ratio (95% CI) for kidney failure/death of 0.89 (0.87-0.92).CONCLUSIONS: Outcomes in this large IgA nephropathy cohort are generally poor with few patients expected to avoid kidney failure in their lifetime. Significantly, patients traditionally regarded as being "low-risk", with proteinuria &lt;0.88 g/g (&lt;100 mg/mmol), have high rates of kidney failure within 10 years.</p

Long-Term Outcomes in IgA Nephropathy

BACKGROUND: IgA nephropathy can progress to kidney failure, and risk assessment soon after diagnosis has advantages both for clinical management and the development of new therapeutics. We present relationships among proteinuria, eGFR slope and lifetime risks for kidney failure. METHODS: The IgA nephropathy cohort (2,299 adults, 140 children) of the UK National Registry of Rare Kidney Diseases (RaDaR) was analyzed. Patients enrolled had a biopsy-proven diagnosis of IgA nephropathy, plus proteinuria >0.5 g/day or eGFR <60 mL/min/1.73m 2 . Incident and prevalent populations were studied as well as a population representative of a typical phase 3 clinical trial cohort. Analyses of kidney survival were conducted using Kaplan-Meier and Cox regression. eGFR slope was estimated using linear mixed models with random intercept and slope. RESULTS: Median (Q1, Q3) follow-up was 5.9 (3.0, 10.5) years; 50% of patients reached kidney failure or died in the study period. Median (95% CI) kidney survival was 11.4 (10.5, 12.5) years; mean age at kidney failure/death was 48 years, and most patients progressed to kidney failure within 10-15 years. Based on eGFR and age at diagnosis, almost all patients are at risk of progression to kidney failure within their expected lifetime unless a rate of eGFR loss ≤1 ml/min/1.73m 2 /year can be maintained. Time-averaged proteinuria was significantly associated with worse kidney survival and more rapid eGFR loss in incident, prevalent, and "clinical trial" populations. 30% of patients with time-averaged proteinuria of 0.44 to <0.88 g/g and approximately 20% of patients with time-averaged proteinuria <0.44 g/g developed kidney failure within 10 years. In the "clinical trial" population each 10% decrease in time-averaged proteinuria from baseline was associated with a hazard ratio (95% CI) for kidney failure/death of 0.89 (0.87-0.92). CONCLUSIONS: Outcomes in this large IgA nephropathy cohort are generally poor with few patients expected to avoid kidney failure in their lifetime. Significantly, patients traditionally regarded as being "low-risk", with proteinuria <0.88 g/g (<100 mg/mmol), have high rates of kidney failure within 10 years

Coastal barium cycling at the West Antarctic Peninsula

Barium cycling in the ocean is associated with a number of processes, including the production and recycling of organic matter, freshwater fluxes, and phenomena that affect alkalinity. As a result, the biogeochemical cycle of barium offers insights into past and present oceanic conditions, with barium currently used in various forms as a palaeoproxy for components of organic and inorganic carbon storage, and as a quasi-conservative water mass tracer. However, the nature of the oceanic barium cycle is not fully understood, particularly in cases where multiple processes may be interacting simultaneously with the dissolved and particulate barium pools. This is particularly the case in coastal polar regions such as the West Antarctic Peninsula, where biological drawdown and remineralisation occur in tandem with sea ice formation and melting, glacial meltwater input, and potential fluxes from shelf sediments.Here, we use a high-precision dataset of dissolved barium (Bad) from a grid of stations adjacent to the West Antarctic Peninsula in conjunction with silicic acid (Si(OH)4), the oxygen isotope composition of water, and salinity measurements, to determine the relative control of various coastal processes on the barium cycle throughout the water column. There is a strong correlation between Bad and Si(OH)4 present in deeper samples, but nevertheless persists significantly in surface waters. This indicates that the link between biogenic opal and barium is not solely due to barite precipitation and dissolution at depth, but is supplemented by an association between Bad and diatom tests in surface waters, possibly due to barite formation within diatom-dominated phytodetritus present in the photic zone. Sea ice meltwater appears to exert a significant secondary control on barium concentrations, likely due to non-conservative biotic or abiotic processes acting as a sink for Bad within the sea ice itself, or sea ice meltwater stimulating non-siliceous productivity that acts as a Bad sink. Meteoric water input, conversely, exerts little or no control on local barium levels, indicating that glacial meltwater is not a significant coastal source of barium to the West Antarctic Peninsula shelf waters.<br/