Robot-Assisted vs. Conventional Laparoscopic Rectopexy for Rectal Prolapse: A Comparative Study on Costs and Time

PURPOSE: Laparoscopic rectopexy has become one of the most advocated treatments for full-thickness rectal prolapse, offering good functional results compared with open surgery and resulting in less postoperative pain and faster convalescence. However, laparoscopic rectopexy can be technically demanding. Once having mastered dexterity, with robotic assistance, laparoscopic rectopexy can be performed faster. Moreover, it shortens the learning curve in simple laparoscopic tasks. This may lead to faster and safer laparoscopic surgery. Robot-assisted rectopexy has been proven safe and feasible; however, until now, no study has been performed comparing costs and time consumption in conventional laparoscopic rectopexy vs. robot-assisted rectopexy. METHODS: Our first 14 cases of robot-assisted laparoscopic rectopexy were reviewed and compared with 19 patients who underwent conventional laparoscopic rectopexy in the same period. RESULTS: Robot-assisted laparoscopic rectopexy did not show more complications. However, the average operating time was 39 minutes longer, and costs were 557.29 (or: $745.09) higher. CONCLUSION: Robot-assisted laparoscopic rectopexy is a safe and feasible procedure but results in increased time and higher costs than conventional laparoscopy. AD - Department of Surgery, Maastricht University Hospital, Maastricht, The Netherlands

Sandbanks, sandwaves and megaripples on Spitsbergenbanken, Barents Sea

Recently acquired multibeam echosounder data from the shallowest part (26–53 m depth) of Spitsbergenbanken in the western Barents Sea reveal a variety of bedforms, including megaripples, sandwaves and sandbanks. The bedforms exhibit varying degrees of superimposition and differ in their age of formation and present depositional regime, being either active or moribund. These are the first observations of co-occurring current induced bedforms in the western Barents Sea and provide evidence of a high energy environment in the study area. The bedforms indicate both sediment erosion and transport and confirm that there is enough sand available in this area to maintain them. Such conditions are not known to be common in the western Barents Sea and reflect the unique oceanographic and benthic environment of Spitsbergenbanken.publishedVersio

A brief introduction to the TrawledSeas Project: Bottom Trawling as a Driver of Seascape Transformation

5th International Network for Submarine Canyon Investigation and Scientific Exchange International Symposium (INCISE), 14-18 June 2021Bottom trawling is one of the most widespread fishing practices in the world’s oceans. It involves towing of nets to harvest benthic and demersal living resources. The dragging of trawling gears along the seafloor results in scraping and ploughing the seabed, which leads to the formation of turbid plumes of resuspended sediments, changes in the sediment erosion/accumulation rates and modifications of their fluxes and budgets, which results in measurable alterations of the submarine geomorphology. As submarine canyons are increasingly targeted by trawlers, there is a growing need to quantify, monitor and mitigate the impacts of bottom trawling in these environments. The TrawledSeas Project aims to quantitatively characterise the contribution of bottom trawling on the geomorphic evolution of submarine canyons, over a range of spatial scales, from fine (m–dam) to mesoscale (5–100 km). To address this objective, a new automated marine landscape mapping technique is being developed to quantify the morphological signature of bottom trawling, based on the analysis of high-resolution multibeam data implemented in a Geographic Information System (GIS). The proposed methodology integrates standard general (e.g. curvature, rugosity, roughness or fractal dimension) and specific (e.g. object-based image methods) geomorphic techniques with new ones developed in this project in a multiscale approach. It combines GIS open source tools with bathymetric dataset at different resolutions, from hull-mounted multibeam data to compare the large-scale morphology of trawled and untrawled areas, to Remotely Operated Vehicles (ROV) and autonomous underwater vehicle (AUV) bathymetric data to identify and quantify trawl marks at small spatial scale. Additionally, data from repeated surveys will be used to assess potential temporal changes in the seafloor morphology of new fishing grounds. The implementation of these geomorphological tools in different study sites incised by submarine canyons (e.g. Catalan, Malta-Sicilian, Norwegian, Canterbury, Patagonian and W Canadian continental margins), will allow to characterise the differential impact of bottom trawling on the canyons’ seafloor, in terms of extent, rates and volume change in different geologic and climatic settingsPeer reviewe

The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015

Late Weichselian and Holocene sedimentary processes and environments in Billefjorden, Svalbard

Three sediment cores, swath multibeam bathymetry data and high-resolution seismic data from Billefjorden, Svalbard have been analysed for a better understanding of the Late Weichselian and Holocene glacier activity as well as sedimentary process and glacigenic deposits in the fjord. The data reveal that glacial linear features were generated in the central part of Billefjorden while it was filled with ice draining the Svalbard-Barents Sea ice sheet during the Last Glacial. A till in the bottom of a sediment core from the central part of the fjord is inferred to have been deposited before the ice front retreated into Billefjorden around 11230 cal. years BP. An overlying glacimarine unit deposited between c. 11230 and 11200 cal. years BP indicates that the glacier retreated from central parts of the fjord to the fjord head in approximately 30 years. Annual recessional moraines deposited during this period suggest that the glacier front retreated approximately 330 m/ year at the end of the last Glacial. High concentration of shells, low amounts of IRD and XRD results indicate a Holocene climatic optimum between c. 11200 – 7930 cal. years BP in which Nordenskiöldbreen was most likely much smaller than it is at present. XRD results and comparatively high amounts of IRD point to a complex pattern of ice rafting between c. 7930 and 3230 cal. BP. IRD deposited before c. 5470 cal. years BP was most likely transported by sea ice, whereas IRD after 5470 cal. years points towards a growth of Nordenskiöldbreen. The time after c. 3230 is mainly characterised by suppressed rafting of sea ice and icebergs because of the possible presence of multi-year shorefast sea ice during the Neoglacial maximum. Glacial lineations on a bedrock terrace in the inner fjord were formed during a Neoglacial advance of Nordenskiöldbreen. Iceberg ploughmarks and recessional moraines were most likely generated during the retreat after the maximum Neoglacial extent of Nordenskiöldbreen. Mass-transport activity in Billefjorden probably occurred throughout the entire Holocene. There might haven been an increased mass-transport activity shortly after the deglaciation of the fjord, because high rates of isostatic uplift might have caused seismic activity. Other triggering mechanisms include the development of oversteepened slopes by high sediment supply and the pushing of sediments at the grounding line of the glacier. Pockmarks in the central part of the fjord were most likely generated by the seepage of thermogenic gas along the Billefjorden fault zone

Mass-movements on the continental slope offshore Lofoten, Northern Norway

Swath bathymetry, side-scan sonar, sub-bottom profiler and seismic data from the continental slope offshore the Lofoten Islands, northern Norway reveal smaller-scale mass movements in water depths between 1100 and 2500 m. These mass movements have volumes of 0.061 to 8.7 km3 and are interpreted as translational slides involving spreading and multi-phase retrogression. The spatial variation in failure style is inferred to have been caused by the activation of different glideplanes (12.5-130 mbsf) within the thicker and more mounded contouritic deposits in the north-east of the study area. Data from a sediment core show that the shallowest style of mass movement (12.5 mbsf), was initiated within contouritic sediments characterized by high sensitivities and water contents. This unit overlies a plumite interval characterized by dilative behavior with pore pressure decrease with increasing shear strain and high undrained shear strength. As such, it is the difference in geotechnical properties which indicates that the interface between these units acts as the basal glide plane, with deformation in the weaker overlying unit. The mass movements in the study area are inferred to have been triggered by undercutting and removal of support at the foot of the slope due to large-scale mass movements that have occurred immediately south of the study area, such as the Trænadjupet or Nyk slides. Furthermore, a network of 2D seismic data reveals the presence of several paleo-canyons. The data illustrate that canyon formation is more extensive then previously thought. These paleo-canyons are buried by an extensive contourite drift interpreted to be a continuation of the Lofoten Drift. The distribution of the drift indicates changes in the depth and strength of paleo-currents. Mass movements only occur in the upper part of the sequence, most likely after the onset of the Pleistocene

Formation of a large submarine crack during the final stage of retrogressive mass wasting on the continental slope offshore northern Norway

High-resolution swath-bathymetry data integrated with sub-bottom profiles and single-channel seismics reveal an 18 km long, up to 1000 m wide and 10-15 m deep crack located approx. 4 km upslope from a slide scar on the continental slope off northern Norway. This crack is formed by subsidence of the sea-floor sediments to a depth of 120 m due to downslope movement of a ~80 km2 large sediment slab that represents the final stage of retrogressive mass wasting in this area. From its morphological freshness, the crack this is inferred to have formed sometime during the last 13 cal. ka BP. These findings add to our understanding of the origin of sea floor cracks on passive continental margins where explanations as slip of normal faults or gas expulsion from the dissociation of gas hydrates previously have been suggested for the formation of cracks in similar settings

Semi-Automatic Versus Manual Mapping of Cold-Water Coral Carbonate Mounds Located Offshore Norway

Cold-water coral reefs are hotspots of biological diversity and play an important role as carbonate factories in the global carbon cycle. Reef-building corals can be found in cold oceanic waters around the world. Detailed knowledge on the spatial location and distribution of coral reefs is of importance for spatial management, conservation and science. Carbonate mounds (reefs) are readily identifiable in high-resolution multibeam echosounder data but systematic mapping programs have relied mostly on visual interpretation and manual digitizing so far. Developing more automated methods will help to reduce the time spent on this laborious task and will additionally lead to more objective and reproducible results. In this paper, we present an attempt at testing whether rule-based classification can replace manual mapping when mapping cold-water coral carbonate mounds. To that end, we have estimated and compared the accuracies of manual mapping, pixel-based terrain analysis and object-based image analysis. To verify the mapping results, we created a reference dataset of presence/absence points agreed upon by three mapping experts. There were no statistically significant differences in the overall accuracies of the maps produced by the three approaches. We conclude that semi-automated rule-based methods might be a viable option for mapping carbonate mounds with high spatial detail over large areas

A Continuous Seismostratigraphic Framework for the Western Svalbard-Barents Sea Margin Over the Last 2.7 Ma: Implications for the Late Cenozoic Glacial History of the Svalbard-Barents Sea Ice Sheet

Here we present a high-resolution, continuous seismostratigraphic framework that for the first time, connects the over 1,000 km long western Svalbard-Barents Sea margin and covers the last ∼2.7 million years (Ma). By exploiting recent improvements in chronology, we establish a set of reliable age fix-points from available boreholes along the margin. We then use a large 2-D seismic database to extend this consistent chronology from the Yermak Plateau and offshore western Svalbard, southwards to the Bear Island Trough-Mouth Fan. Based on this new stratigraphic framework we divide the seismic stratigraphy along the continental margin into three seismic units, and 12 regionally correlated seismic reflections, each with an estimated age assignment. We demonstrate one potential application of this framework by reconstructing the Svalbard-Barents Sea Ice Sheet evolution from the intensification of the northern hemisphere glaciation at ∼2.7 Ma to the Weichselian glaciations. Through seismic facies distribution and sedimentation rate fluctuations along the margin we distinguish three phases of glacial development. The higher temporal resolution provided by this new framework, allows us to document a clear two-step onset to glacial intensification in the region during phase 1, between ∼2.7 and 1.5 Ma. The initial step, between ∼2.7 and 2.58 Ma shows glacial expansion across Svalbard. The first indication of shelf-edge glaciation is on the Sjubrebanken Trough-Mouth Fan, northwestern Barents Sea after ∼2.58 Ma; whilst the second step, between ∼1.95 and 1.78 Ma shows glacial advances beyond Svalbard to the northwestern Barents Sea. Phase 2 is characterized by variations in sedimentation rates and the seismic facies are indicative for a regional glacial intensification for the whole Barents Sea-Svalbard region with widespread shelf-edge glaciations recorded at around ∼1.5 Ma. During Phase 3, the western Barents Sea margin is characterized by a dramatic increase in sedimentation rates, inferring once again a regional glacial intensification. Our new stratigraphic framework allows for the first time differentiation of the sediments deposited on the slope during Early Saalian (∼0.4 and 0.2 Ma), Late Saalian (∼0.2 and 0.13 Ma), and Weichselian (<∼0.123 Ma) periods, providing new insights into the Barents Sea glaciations over the last ∼0.42 Ma