306 research outputs found

    Deep-water observation of scalloped hammerhead Sphyrna lewini in the western Indian Ocean off Tanzania

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    A scalloped hammerhead Sphyrna lewini was observed opportunistically from a remotely operated vehicle 1 m off the seabed at 1042 m depth, during hydrocarbon exploration activities in the Ruvuma Basin off Tanzania. The observation, which occurred during night hours, is the deepest accurately recorded for this species and the first deep-water record for the Indian Ocean. The record adds support for the occurrence in deep water during night hours being a widespread and possibly common behaviour in this species, and further expands a small but growing literature that meso- and bathypelagic environments may be of greater importance to elasmobranchs previously considered to be primarily epipelagic

    RRS Discovery Cruise 116, 10 November - 27 November 2020, Time-series studies at the Porcupine Abyssal Plain Sustained Observatory

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    RRS Discovery cruise 116 departed Southampton 10th November 2020, operated in the Whittard Canyon (12-13th November) and the Porcupine Abyssal Plain Sustained Observatory area (19-23 November), returning to Southampton 26th November 2020. The goal of the cruise was to continue time-series observations of the surface ocean, water column, and seafloor at the site, as first studied by NOC (then the Institute of Oceanographic Sciences) in 1985. An additional goal was to service a mooring at Whittard Canyon. Operations were limited in scope because of the Covid-19 pandemic which affected all aspects of life in 2020. DY116 was delayed from June/July until November 2020 and proceeded with reduced personnel and limited scope. The specific aims were to recover data and infrastructure and deploy replacement moorings. The regular sampling programme at PAP-SO did not take place because of the need for social distancing. Shortly before departing the PAP1 surface buoy had become detached from the mooring and was recovered by the FS Maria S. Merian. The PAP1 mooring was successfully deployed including replacement of the full ocean depth mooring. The surface buoy was upgraded to a Met Office Mobilis buoy. The 30 m sensor frame was not included in the first deployment but will return on in 2021. The PAP3 mooring, a sediment trap and current meter string, was successfully recovered and redeployed. Colonisation substrates and larval traps for the on-going LO3CAted (Larval Occurrences in Open Ocean: Connectivity studies in NE Atlantic and Mediterranean Sea) project were recovered from PAP3. The Bathysnap seafloor time-lapse camera, and associated LO3CAted samplers, was recovered but unfortunately it had flooded. A series of water column observation and sampling operations were successfully carried out with a CTD instrument package. The CTD deployments included pre-and post-deployment calibrations of PAP1 and PAP3 sensors. Underway data were collected and a Met Office Biogeochemistry Argo float was deployed. At Whittard Canyon the mooring was successfully recovered and replaced. This cruise was a contribution to the Climate Linked Atlantic Section Science (CLASS) project supported by the UK Natural Environment Research Council (grant number NE/R015953/1)

    SERPENT Activity Report: Lincoln 205/26b-14 and Warwick Crestal. 2019. UK.

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    In 2019 National Oceanography Centre scientists carried out a field campaign at Hurricane Energy’s Lincoln 205/26b-14 and Warwick Crestal 204/30b-A sites west of Shetland, through Hurricane’s involvement in the SERPENT Project. Previous SERPENT observations have revealed the impacts of sedimentation disturbance from the open hole phase of hydrocarbon drilling. This work showed some evidence for different faunal responses over time following the sedimentation event, including evidence for recovery of the abundance and diversity of organisms living within the impacted area. The interpretation of these changes is limited because data only exist over coarse time scales necessary when completing visits pre-drilling, post-drilling and return visits to the sites (e.g. months to years). The primary aim of the field visits to the Transocean Leader in 2019 were to understand the responses of seafloor organisms to sedimentation disturbance over finer temporal scales (e.g. minutes to hours) within the context of the existing knowledge of the effects of sedimentation at hydrocarbon drilling sites. This was addressed using seafloor video survey techniques and time-lapse photography of seafloor organisms during sedimentation events

    Cp*Fe(Me2PCH2CH2PMe2)(CHO) : hydride shuttle reactivity of a thermally stable formyl complex.

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    [Cp*Fe(Me2PCH2CH2PMe2)(CO)]+ [BArF24]− has been synthesised and characterised using single crystal X-ray diffraction, NMR and IR spectroscopies. Reduction of the CO ligand using Na[Et3BH] produces the corresponding neutral formyl complex Cp*Fe(Me2PCH2CH2PMe2)(CHO), that is very thermally stable, and which is attributed to the electron-releasing properties of the spectator ligands. This compound is a potent hydride donor which exists in equilibrium with [Et3BH]−, Et3B, and the structural isomer (η4-C5Me5H)Cp*Fe(Me2PCH2CH2PMe2)(CO), resulting from reversible hydride migration to the Cp* ligand

    Montmorency cherry supplementation attenuates vascular dysfunction induced by prolonged forearm occlusion in overweight, middle-aged men

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    Flavonoid supplementation improves brachial artery flow-mediated dilation (FMD), but it is not known whether flavonoids protect against vascular dysfunction induced by ischemia-reperfusion (IR) injury and associated respiratory burst. In a randomized, double-blind, placebo-controlled, crossover study, we investigated whether 4 wk supplementation with freeze-dried Montmorency cherry (MC) attenuated suppression of FMD after IR induced by prolonged forearm occlusion. Twelve physically inactive overweight, middle-aged men (52.8 ± 5.8 yr, BMI: 28.1 ± 5.3 kg/m2) consumed MC (235 mg/day anthocyanins) or placebo capsules for 4 wk, with supplementation blocks separated by 4 wk washout. Before and after each supplementation block, FMD responses and plasma nitrate and nitrite ([ N O − 2 ]) concentrations were measured at baseline and 15, 30, and 45 min after prolonged (20 min) forearm occlusion. FMD response was significantly depressed by the prolonged occlusion ( P < 0.001). After a 45-min reperfusion, FMD was restored to baseline levels after MC (ΔFMD presupplementation: -30.5 ± 8.4%, postsupplementation: -0.6 ± 9.5%) but not placebo supplementation (ΔFMD presupplementation: -11.6 ± 10.6, postsupplementation: -25.4 ± 4.0%; condition × supplement interaction: P = 0.038). Plasma [ N O − 2 ] decreased after prolonged occlusion but recovered faster after MC compared with placebo (Δ45 min to baseline; MC: presupplementation: -15.3 ± 9.6, postsupplementation: -6.2 ± 8.1; Placebo: presupplementation: -16.3 ± 5.9, postsupplementation: -27.7 ± 11.1 nmol/l; condition × supplement × time interaction: P = 0.033). Plasma peroxiredoxin concentration ([Prx2]) was significantly higher after MC (presupplementation: 22.8 ± 1.4, postsupplementation: 28.0 ± 2.4 ng/ml, P = 0.029) but not after placebo supplementation (presupplementation: 22.1 ± 2.2, postsupplementation: 23.7 ± 1.5 ng/ml). In conclusion, 4 wk MC supplementation enhanced recovery of endothelium-dependent vasodilatation after IR, in parallel with faster recovery of plasma [ N O − 2 ], suggesting NO dependency. These protective effects seem to be related to increased plasma [Prx2], presumably conferring protection against the respiratory burst during reperfusion. NEW & NOTEWORTHY This is the first study to demonstrate that 4 wk of Montmorency cherry powder supplementation exerted protective effects on endothelium-dependent vasodilation after transient ischemia-reperfusion injury in overweight, physically inactive, nonmedicated, hypertensive middle-aged men. These effects seem to be due to increased nitric oxide availability, as evidenced by higher plasma nitrite concentration and peak arterial diameter during the flow-mediated dilation measurement. This may be a consequence of increased concentration of peroxiredoxin and other antioxidant systems and, hence, reduced reactive oxygen species exposure.This article is freely available via Open Access. Click on the Publisher URL to access it via the publisher's site.This study was partially funded by a grant from the Cherry Research Committee, Aboo-Bakkar was supported by a Ph.D. studentship from the Universiti Kuala Lumpur, and Fulford’s salary was provided by National Institute for Health Research.accepted version (12 month embargo

    First in-situ monitoring of sponge response and recovery to an industrial sedimentation event

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    Assessment of risks to seabed habitats from industrial activities is based on the resilience and potential for recovery. Increased sedimentation, a key impact of many offshore industries, results in burial and smothering of benthic organisms. Sponges are particularly vulnerable to increases in suspended and deposited sediment, but response and recovery have not been observed in-situ. We quantified the impact of sedimentation from offshore hydrocarbon drilling over ∼5 days on a lamellate demosponge, and its recovery in-situ over ∼40 days using hourly time-lapse photographs with measurements of backscatter (a proxy of suspended sediment) and current speed. Sediment accumulated on the sponge then cleared largely gradually but occasionally sharply, though it did not return to the initial state. This partial recovery likely involved a combination of active and passive removal. We discuss the use of in-situ observing, which is critical to monitoring impacts in remote habitats, and need for calibration to laboratory conditions

    Infection with cerebral metacercariae of microphallid trematode parasites reduces reproductive output in the gammarid amphipod Gammarus insensibilis (Stock 1966) in UK saline lagoons

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    Saline lagoons are priority habitats in the United Kingdom supporting several protected specialist species. One specialist, the amphipod Gammarus insensibilis, is infected with behaviour-altering microphallid trematodes such as Microphallus papillorobustus. In saline lagoons around the coast of England (Gilkicker and Lymington–Keyhaven on the Hampshire coast and Moulton Marsh in Lincolnshire) there is variation in the prevalence of this parasite in the gammarid populations (0 at Salterns in the Lymington–Keyhaven lagoon system to 98% at Gilkicker). Infection intensity ranged from 0 to 20 metacercariae in individual amphipods. Higher infection intensity can alter the shape of the amphipod's head. Under experimental conditions respiration rate is significantly reduced in infected animals and reproductive output (expressed as early stage embryos mg g dry weight−1) is significantly lower in infected females. It is important to consider the role of host–parasite interactions in order to understand the ecology of specialist lagoon species such as G. insensibilis and their lagoon habitats

    An association between a cusk eel (Bassozetus sp.) and a black coral (Schizopathes sp.) in the deep western Indian Ocean

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    Detailed observations in the deep sea can reveal previously unknown behaviour, species interactions and fine-scale habitat heterogeneity. Here, the first in situ images of the black coral Schizopathes sp. (Anthozoa: Antipatharia) in the deep western Indian Ocean have been obtained from remotely operated vehicle video footage and time-lapse photography. In these images, there appears to be an association with the cusk eel Bassozetus (Family: Ophidiidae). In the primary observation, chance encounters revealed the fish interacted with the anitpatharian on multiple occasions over several days. Subsequent time-lapse camera footage showed the fish remained almost exclusively underneath the antipatharian for the duration of a 30-h deployment. Excursions from the cover of the antipatharian were for less than 2 min. The primary observation is supported by two similar encounters in the same region. Observed reduction in the tail-beat frequency of the fish under the antipatharian suggests reduced energy requirements for the ophidiid in this position. The observations demonstrate the role that even individual coral colonies play as a source of three-dimensional structure, providing habitat heterogeneity in the deep sea

    Autonomous marine environmental monitoring: Application in decommissioned oil fields

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    Hundreds of Oil & Gas Industry structures in the marine environment are approaching decommissioning. In most areas decommissioning operations will need to be supported by environmental assessment and monitoring, potentially over the life of any structures left in place. This requirement will have a considerable cost for industry and the public. Here we review approaches for the assessment of the primary operating environments associated with decommissioning — namely structures, pipelines, cuttings piles, the general seabed environment and the water column — and show that already available marine autonomous systems (MAS) offer a wide range of solutions for this major monitoring challenge. Data of direct relevance to decommissioning can be collected using acoustic, visual, and oceanographic sensors deployed on MAS. We suggest that there is considerable potential for both cost savings and a substantial improvement in the temporal and spatial resolution of environmental monitoring. We summarise the trade-offs between MAS and current conventional approaches to marine environmental monitoring. MAS have the potential to successfully carry out much of the monitoring associated with decommissioning and to offer viable alternatives where a direct match for the conventional approach is not possible
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