Detecting responses of rocky shore organisms to environmental change following wave energy extraction

The highly energetic waters surrounding Orkney have recently attracted attention as a renewable resource to generate electricity. While the importance of wave exposure to littoral assemblages is well known, the ecological consequences of industrial-scale extraction of marine energy have not been directly studied on rocky shores. The aim of this study was to examine the potential consequences of wave energy extraction and other long-term forcing agents, such as climate change, to rocky shore assemblages. Baseline surveys were conducted in areas not previously described in scientific detail to serve as ‘before’ and ‘control’ sites in a BACI-style design. Composition and abundances of biological assemblages were compared with topographic measurement of coastal features expected to modify exposure through dissipation of incoming wave energy. Observed variation in assemblages between sites was explained by differences in exposure and topography, particularly substrate complexity. Rocky shore species were selected for monitoring long-term changes using a paired-species monitoring method, including key structuring organisms on high exposure shores. Monitoring and experimental manipulation identified species which respond to changes in wave energy extraction and temperature. This research will assist in elucidating ecological responses that might occur following removal of wave energy, amid warming seas

Key Biofouling Organisms in Tidal Habitats Targeted by the Offshore Renewable Energy Sector in the North Atlantic Include the Massive Barnacle Chirona hameri

Marine habitats are being targeted for the extraction of offshore renewable energy (ORE) as part of the drive to decarbonise electricity generation. Unmanaged biofouling impacts ORE devices and infrastructure by elevating drag forces, increasing weight, and accelerating corrosion, leading to decreased performance and survivability, and extending costly periods of maintenance. ORE deployments in high tidal flow locations are providing opportunities to study the biofouling unique to these habitats. In this study, surveys of numerous devices and associated infrastructure deployed at the European Marine Energy Centre in Scotland identified high tidal flow fouling assemblages. Substrate orientation relative to tidal flow appears to affect the abundance of key fouling species, including the massive barnacle Chirona hameri. This species is shown to recruit to a wide range of artificial substrates, over a prolonged period from mid-spring to mid-summer, and in maximum current speeds from 0.4–4.0 m/s. For the first time, C. hameri is reported in near-surface depths, on uncoated components of a floating tidal device. The highly gregarious settlement behaviour and rapid growth exhibited by this species may have important implications for managing fouling in the ORE industry, especially in ‘niche’ areas. Anti-fouling strategies and maintenance scheduling applicable to ORE and other marine industries are discussed

Multiparameter flow cytometry for the characterization of human embryonic stem cells

Using multiparameter staining methods and flow cytometry to investigate the pluripotency of HUES7 human embryonic stem cell cultures, it was found that the multidimensional approach of marker co-expression allowed the different cell populations to be easily identified and demonstrated cross reactivity between the SSEA 4 and SSEA 1 antibodies, resulting in a substantial false positive SSEA 1 population. It is the accepted norm to apply control gates at a 95 % confidence level of the isotype control; however, this study found that adjusting the control gate to a 99 % confidence level significantly reduced the effect of this cross reactivity. Though conversely, this gating shift also decreased the positive marker expression of SSEA 4 and Tra-1-60, indicating that there is a need for strongly expressing markers coupled with increased optimization of fluorophore/antibody combinations before a gating strategy of 99 % can be implemented on a more routine basis

A review of potential impacts of submarine power cables on the marine environment:Knowledge gaps, recommendations and future directions

Submarine power cables (SPC) have been in use since the mid-19th century, but environmental concerns about them are much more recent. With the development of marine renewable energy technologies, it is vital to understand their potential impacts. The commissioning of SPC may temporarily or permanently impact the marine environment through habitat damage or loss, noise, chemical pollution, heat and electromagnetic field emissions, risk of entanglement, introduction of artificial substrates, and the creation of reserve effects. While growing numbers of scientific publications focus on impacts of the marine energy harnessing devices, data on impacts of associated power connections such as SPC are scarce and knowledge gaps persist. The present study (1) examines the different categories of potential ecological effects of SPC during installation, operation and decommissioning phases and hierarchizes these types of interactions according to their ecological relevance and existing scientific knowledge, (2) identifies the main knowledge gaps and needs for research, and (3) sets recommendations for better monitoring and mitigation of the most significant impacts. Overall, ecological impacts associated with SPC can be considered weak or moderate, although many uncertainties remain, particularly concerning electromagnetic effects

Studies related to antibody fragment (Fab) production in Escherichia coli W3110 fed-batch fermentation processes using multiparameter flow cytometry

Background: Microbiology is important to industry therefore rapid and statistically representative measurements of cell physiological state, proliferation and viability are essential if informed decisions about fermentation bioprocess optimisation or control are to be made, since process performance will depend largely upon the number of metabolically active viable cells. Methods: Samples of recombinant Escherichia coli W3110, containing the gene for the D1.3 anti-lysozyme Fab fragment under the control of the lac based expression system, were taken at various stages from fed-batch fermentation processes and stained with a mixture of bis-(1, 3-dibutylbarbituric acid) trimethine oxonol and propidium iodide (PI/BOX). Where appropriate, measurements of dissolved oxygen tension (DOT), OD600nm and Fab concentration were made. Results: Depending on time of induction the maximum amount of Fab accumulating in the supernatant varied quite markedly from 1 – 4 μgml-1 as did subsequent cell physiological state with respect to PI/BOX staining with a concomitant drop in maximum biomass concentration. Conclusion: Depending on point of induction a 4 fold increase in Fab production could be achieved accompanied by a ~50% drop in maximum biomass concentration but with a higher proportion of viable cells as measured by multi-parameter flow cytometry

Biodiversity characterisation and hydrodynamic consequences of marine fouling communities on submerged marine structures in the Orkney Islands Archipelago, Scotland, UK.

<p>As part of ongoing commitments to produce electricity from renewable energy sources in Scotland, Orkney waters have been targeted for potential large-scale deployment of wave and tidal energy converting devices. Orkney has a well-developed infrastructure supporting the marine energy industry; recently enhanced by the construction of additional piers. A major concern to marine industries is biofouling on submerged structures, including energy converters and measurement instrumentation. In this study, the marine energy infrastructure and instrumentation were surveyed to characterise the biofouling. Fouling communities varied between deployment habitats; key species were identified allowing recommendations for scheduling device maintenance and preventing spread of invasive organisms. A method to measure the impact of biofouling on hydrodynamic response is described and applied to data from a wave-monitoring buoy deployed at a test site in Orkney. The results are discussed in relation to the accuracy of the measurement resources for power generation. Further applications are suggested for future testing in other scenarios, including tidal energy.</p

Biodiversity characterisation and hydrodynamic consequences of marine fouling communities on submerged marine structures in the Orkney Islands Archipelago, Scotland, UK.

As part of ongoing commitments to produce electricity from renewable energy sources in Scotland, Orkney waters have been targeted for potential large-scale deployment of wave and tidal energy converting devices. Orkney has a well-developed infrastructure supporting the marine energy industry; recently enhanced by the construction of additional piers. A major concern to marine industries is biofouling on submerged structures, including energy converters and measurement instrumentation. In this study, the marine energy infrastructure and instrumentation were surveyed to characterise the biofouling. Fouling communities varied between deployment habitats; key species were identified allowing recommendations for scheduling device maintenance and preventing spread of invasive organisms. A method to measure the impact of biofouling on hydrodynamic response is described and applied to data from a wave-monitoring buoy deployed at a test site in Orkney. The results are discussed in relation to the accuracy of the measurement resources for power generation. Further applications are suggested for future testing in other scenarios, including tidal energy

Multi-parameter flow cytometry and cell sorting reveal extensive physiological heterogeneity in Bacillus cereus batch cultures.

Based on two staining protocols, DiOC6(3)/ propidium iodide (PI) and RedoxSensor Green (an indicator of bacterial reductase activity)/PI, multiparameter flow cytometry and cell sorting has identified at least four distinguishable physiological states during batch cultures of Bacillus cereus. Furthermore, dependent on the position in the growth curve, single cells gave rise to varying numbers of colonies when sorted individually onto nutrient agar plates. These growing colonies derived from a single cell had widely different lag phases, inferred fromdifferences in colony size.This further highlights the complex population dynamics of bacterial monocultures and further demonstrates that individual bacterial cells in a culture respond in markedly dissimilar ways to the environment, resulting in a physiologically heterogenous and dynamic population

Blue carbon audit of Orkney waters

This study provides an audit of the potential blue carbon resources present in the coastal waters around Orkney, bounded by the 12 nautical mile limit and including the Loch of Stenness brackish water lagoon. This report builds on previous work in which blue carbon stocks in Marine Protected Areas in Scottish waters were estimated from i) contributions of biological material to the fixation of carbon, also referred to as production, and ii) contributions of sediments to blue carbon storage. The methodology has been further developed here to allow regional-scale estimation of habitat extent and provides estimates of blue carbon associated with habitats and surface sediments.Publisher PD

Brain-derived neurotrophic factor released from blood platelets prevents dendritic atrophy of lesioned adult central nervous system neurons

In humans and other primates, blood platelets contain high concentrations of brain-derived neurotrophic factor due to the expression of the BDNF gene in megakaryocytes. By contrast, mice, typically used to investigate the impact of CNS lesions, have no demonstrable levels of brain-derived neurotrophic factor in platelets, and their megakaryocytes do not transcribe significant levels of the Bdnf gene. Here, we explore potential contributions of platelet brain-derived neurotrophic factor with two well-established CNS lesion models, using ‘humanized’ mice engineered to express the Bdnf gene under the control of a megakaryocyte-specific promoter. Retinal explants prepared from mice containing brain-derived neurotrophic factor in platelets were labelled using DiOlistics and the dendritic integrity of retinal ganglion cells assessed after 3 days by Sholl analysis. The results were compared with retinas of wild-type animals and with wild-type explants supplemented with saturating concentrations of brain-derived neurotrophic factor or the tropomyosin kinase B antibody agonist, ZEB85. An optic nerve crush was also performed, and the dendrites of retinal ganglion cells similarly assessed 7-day post-injury, comparing the results of mice containing brain-derived neurotrophic factor in platelets with wild-type animals. In mice engineered to contain brain-derived neurotrophic factor in platelets, the mean serum brain-derived neurotrophic factor levels were 25.74 ± 11.36 ng/mL for homozygous and 17.02 ± 6.44 ng/mL for heterozygous mice, close to those determined in primates. Retinal explants from these animals showed robust preservation of dendrite complexity, similar to that seen with wild-type explants incubated with medium supplemented with brain-derived neurotrophic factor or the tropomyosin receptor kinase B antibody agonist, ZEB85. The Sholl areas under curve were 1811 ± 258, 1776 ± 435 and 1763 ± 256 versus 1406 ± 315 in the wild-type control group (P ≤ 0.001). Retinal ganglion cell survival based on cell counts was similar in all four groups, showing ∼15% loss. A robust neuroprotective effect was also observed following optic nerve crush when assessing the dendrites of the retinal ganglion cells in the transgenic mouse, with Sholl area under the curve significantly higher compared to wild-type (2667 ± 690 and 1921 ± 392, P = 0.026), with no significant difference in the contralateral eye controls. Repeat experiments found no difference in cell survival, with both showing ∼50% loss. These results indicate that platelet brain-derived neurotrophic factor has a strong neuroprotective effect on the dendrite complexity of retinal ganglion cells in both an ex vivo and in vivo model, suggesting that platelet brain-derived neurotrophic factor is likely to be a significant neuroprotective factor in primates