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Conservation science increasingly focuses on how ecosystem functioning is affected by anthropogenic pressures, which implies an understanding of the structural and functional changes in biological assemblages and requires indicators to detect such changes within a suitable time frame. A novel approach that combines the spatial analysis of fishing gradients (based on vessel monitoring system records) with distance‐based linear models was used to assess the response of several functional and structural metrics of fish assemblages to gradients of trawling, within four distinct habitat types. In addition, critical thresholds of trawling intensity were identified for the most sensitive metrics through piecewise regression models. Overall, total biomass and dominance (i.e. number of species that make up 90% of the total biomass) metrics as well as metrics representing vulnerable features (such as chondrichthyes, species with very low resilience and sedentary species) were shown to be sensitive to fishing. Our results suggest that decreasing trends in these indicators are likely to be associated with direct and indirect fishing effects acting synergistically on specific features of fish assemblages leading to its homogenization, with likely impacts on ecosystems resilience. Critical thresholds at high, medium and low fishing intensity levels were identified depending on the metric used to assess fishing impacts, suggesting that it is difficult to define a single global target for fishing management as it ultimately will depend on management and conservation objectives (e.g. maintenance of biomass vs. maintenance of structure and function). Synthesis and applications. A key goal of the applied approach was to provide short‐term indicators that are sensitive to gradients of trawling intensity and can be extrapolated to a broader geographical region. The identification of thresholds of fishing pressure that fish assemblages can withstand before ecosystem functioning is altered is key for the development of indicators as warning mechanisms, as well as to assess performance measures for management. Understanding responses to other pressure sources (e.g. pollution, dredging) requires further research, and combining an integrative functional traits approach with a wider range of pressures may help make this achievable.

Motility is defined as the movement of cells by some form of self-propulsion. Some organisms motile by using long flagella that quickly rotate to propel them over various surfaces (in swarming and swimming mechanism), while few motile without the aid of flagella (in twitching, sliding and gliding mechanism). Among these modes, gliding motility is adopted by a rod-shaped organism famously known as gliding bacteria. It is hypothesized that in such type of motility, organism motile under their own power by secreting a layer of slime on the substrate. In this study, an active wall is considered as a substrate and a two-dimensional wavy sheet as an organism. Slip effects are also employed in the current work. The physical properties of the slime are governed by a suitable constitutive equation of couple stress model. A sixth order BVP is obtained by utilizing lubrication assumption. For an appropriate fixed pair of flow rate and organism speed the BVP is solved by MATLAB built-in function bvp-5c. This solution is utilized in the mechanical equilibrium conditions which are obviously not satisfied yet. To satisfy these conditions, the pair of flow rate and gliding speed is refined by a root finding algorithm (modified Newton–Raphson method). By employing this numerical scheme, various figures are shown to demonstrate the effect of several associated parameters on organism speed, flow rate, energy expended by the glider, streamlines and longitudinal velocity. It is observed from the graphical results that organism speed and energy consumption is directly proportional to the couple stress parameter and slip effects. •The hydrodynamics of micro-organism near a soft surface are investigated.•Problem is based on creeping flow and long wavelength approximation.•Slime is taken as Couple stress fluid present on a slippery boundary.•Gliding speed can be controlled via adjusting fluid parameters.

It is hypothesized that gliding bacteria move by producing waves on their own surface and leave an adhesive slime trail. Slime is basically a viscoelastic slippery material. Based on these observations, we use a mathematical model (of undulating sheet) to examine the locomotion of gliding bacteria over a layer of non-Newtonian slime. The constitutive equations of FENE-P model are employed to characterize the rheological behavior of the non-Newtonian slime. Moreover, substratum beneath the slime is approximated by a multi-sinusoidal sheet. A hybrid computational technique to solve the second order DE with a system of algebraic equations is presented. The speed of organism, flow rate and energy loss at larger values of the involved parameters are simulated using bvp5c in conjunction with a modified Newton-Raphson technique (MNRT). The comparison of soft and rigid substrate, slip and no-slip boundary conditions, Newtonian and non-Newtonian slime is displayed in several figures. Streamlines pattern and velocity of the slime are also drawn for the realistic pairs of speed and flow rate and are thoroughly explained. •A FENE-P fluid flow is created via organism locomotion.•A hybrid numerical procedure is adopted to calculate cell speed.•The comparison of slip and no-slip conditions is also expounded.•Substrate is taken as both rigid and wavy surface.

This paper presents the free and constrained inflation of a pre-stretched hyperelastic cylindrical membrane and a subsequent constrained deflation. The membrane material is assumed as a homogeneous and isotropic Mooney-Rivlin solid. The constraining soft cylindrical substrate is assumed to be a distributed linear stiffness normal to the undeformed surface. Both frictionless and adhesive contact are modelled during the inflation as an interaction between the dry surfaces of the membrane and the substrate. An adhesive contact is modelled during deflation. The free and constrained inflation yields governing equations and boundary conditions, which are solved by a finite difference method in combination with a fictitious time integration method. Continuity in the principal stretches and stresses at the contact boundary is dependent on the contact conditions and inflation-deflation phase. The pre-stretch has a counterintuitive softening effect on free and constrained inflation. The variation of limit point pressures with pre-stretch and the occurrence of a cusp point is shown. Interesting trends are observed in the stretch and stress distributions after the interaction of the membrane with soft substrate, which underlines the effect of material parameters, pre-stretch and constraining properties.

Marine ecosystems, ranging from coastal seas and wetlands to the open ocean, accommodate a wealth of biological diversity from small microorganisms to large mammals. This biodiversity and its associated ecosystem function occurs across complex spatial and temporal scales and is not yet fully understood. Given the wide range of external pressures on the marine environment, this knowledge is crucial for enabling effective conservation measures and defining the limits of sustainable use. The development and application of omics-based approaches to biodiversity research has helped overcome hurdles, such as allowing the previously hidden community of microbial life to be identified, thereby enabling a holistic view of an entire ecosystem’s biodiversity and functioning. The potential of omics-based approaches for marine ecosystems observation is enormous and their added value to ecosystem monitoring, management, and conservation is widely acknowledged. Despite these encouraging prospects, most omics-based studies are short-termed and typically cover only small spatial scales which therefore fail to include the full spatio-temporal complexity and dynamics of the system. To date, few attempts have been made to establish standardised, coordinated, broad scaled, and long-term omics observation networks. Here we outline the creation of an omics-based marine observation network at the European scale, the European Marine Omics Biodiversity Observation Network (EMO BON). We illustrate how linking multiple existing individual observation efforts increases the observational power in large-scale assessments of status and change in biodiversity in the oceans. Such large-scale observation efforts have the added value of cross-border cooperation, are characterised by shared costs through economies of scale, and produce structured, comparable data. The key components required to compile reference environmental datasets and how these should be linked are major challenges that we address.

Lagoon soft-bottoms are key habitats within coral reef seascapes. Coral reef fish use these habitats as nurseries, feeding grounds and transit areas. At present, most soft-bottom sampling methods are destructive (trawling, longlining, hook and line). We developed a remote, unbaited 360° video sampling method (RUV360) to monitor fish species assemblages in soft bottoms. A low-cost, high-definition camera enclosed in a waterproof housing and fixed on a tripod was set on the sea floor in New Caledonia from a boat. Then, 534 videos were recorded to assess the efficiency of the RUV360. The technique was successful in sampling bare soft-bottoms, seagrass beds, macroalgae meadows and mixed soft-bottoms. It is easy to use and particularly efficient, i.e., 88% of the stations were sampled successfully. We observed 10,007 fish belonging to 172 species, including 45 species targeted by fishermen in New Caledonia, as well as many key species. The results are consistent with the known characteristics of the lagoon soft bottom fish assemblages of New Caledonia. We provide future users with general recommendations and reference plots to estimate the proportion of the theoretical total species richness sampled, according to the number of stations or the duration of the footage.

To reveal the dynamic evolution process of slope destabilization of soft substrate waste dump slope under vibration, the block stacking loose slope simulation test system was used to carry out the relevant research, and the stage characteristics of the soft substrate waste dump destabilization under vibration were quantitatively analyzed; the Rosin–Rammler distribution function, which describes the distribution characteristics of the loose medium in the waste dump, was modified based on the concept of the relative height. The results show that the particle size distribution of the loose media in the waste dump has obvious correlation with the relative height, and the modified Rosin–Rammler distribution can better describe the relationship between the two; when the vibration frequency is ≤ 20 Hz, the small particles on the slope surface of the waste dump experience slight slip, while medium and large particle sizes are basically in the stable state, accompanied by the phenomenon of vibration compaction. When the vibration frequency > 20 Hz, there is a small range of slippage on the slope surface of the waste dump slope, with the increase of vibration frequency, the slippage range of the slope surface of the waste dump slope is gradually enlarged, accompanied by particles sliding and flowing, ultimately forming a large range of slippage and bench surface damage, and causing the dynamic instability of the waste dump. The research results can provide fundamental support for the study of dynamic instability of waste dump slopes.

Cell rolling on vascular endothelium under hydrodynamic blood flow is critical for realization of many physiological and pathological processes, such as inflammatory response and tumor metastasis. The blood-borne cells are in direct contact with the inner layer of endothelium, formed by a highly compliant layer of endothelial cells. The effect of endothelial stiffness on the adhesion and motion of rolling cells is poorly understood. Inspired by recent in vitro studies, here we implemented a computational method to model the specific adhesion of a rolling cell onto a soft substrate, subjected to a creeping shear flow. The substrate is modeled as an elastic half-space, coated with P- and E-selectin receptors with specific affinity for the complementary ligands located on the moving cell. Of particular importance is to predict the effect of substrate stiffness on cell adhesion and its kinematics and kinetics of motion. Simulation results show that the effect of substrate compliance is minimal when coated with P-selectin. Conversely, the trajectory of rolling cells on E-selectin coated substrates is sensitive to the substrate compliance. This is attributed to the moderation of binding forces applied by the soft substrate which leads to a higher average translational velocity of cells.

Wearable sensors are rapidly gaining influence in the diagnostics, monitoring, and treatment of disease, thereby improving patient outcomes. In this review, we aim to explore how these advances can be applied to magnetic resonance imaging (MRI). We begin by (i) introducing limitations in current flexible/stretchable RF coils and then move to the broader field of flexible sensor technology to identify translatable technologies. To this goal, we discuss (ii) emerging materials currently used for sensor substrates, (iii) stretchable conductive materials, (iv) pairing and matching of conductors with substrates, and (v) implementation of lumped elements such as capacitors. Applicable (vi) fabrication methods are presented, and the review concludes with a brief commentary on (vii) the implementation of the discussed sensor technologies in MRI coil applications. The main takeaway of our research is that a large body of work has led to exciting new sensor innovations allowing for stretchable wearables, but further exploration of materials and manufacturing techniques remains necessary, especially when applied to MRI diagnostics.

With the construction of wind farms, new hard substrates are introduced in the marine environment. Between the turbine rows and around the wind farms, however, the soft sediments remain. The inhabiting fauna of these sandy sediments may be influenced by the presence of the turbines and the absence of fisheries in the wind farms. These effects were investigated for epibenthos, demersal fish, and benthopelagic fish in the Thorntonbank and Bligh Bank wind farms in the Belgian part of the North Sea. Inside the wind farms, several local and temporal effects were detected, including both temporary construction effects (e.g., decreased densities of dab, ophiuroids and dragonets) as refugium effects (e.g., the presence of relatively large plaice). At the wind farm edges, only few temporary effects were noted, but real edge effects due to changes in fisheries intensity or ‘spillover’ from the wind farms could not be shown. The observed effects were not consistent between both wind farms, which is not surprising, given the differences in epibenthos and fish communities, sandbank topography, fishing pressure, development stage of the wind farms, and the used foundation types. This inconsistency stresses the importance to replicate monitoring activities across wind farms and along the identified gradients.