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Wind turbine flow field prediction is difficult as it requires computationally expensive computational fluid dynamics (CFD) models. The contribution of this paper is to propose and develop a method for stochastic analysis of an offshore wind farm using CFD and a non-intrusive stochastic expansion. The approach is developed through testing a range of machine-learning methods, evaluating dataset requirements and comparing the accuracy against site measurement data. The approach used is detailed and the results are compared with real measurements obtained from the existing wind farm to quantify the accuracy of the predictions. An existing offshore wind farm is modelled using a steady-state CFD solver at several deterministic input ranges and an approximation model is trained on the CFD results. The approximation models compared are Artificial Neural Networks, Gaussian Process, Radial Basis Function, Random Forest and Support Vector Regression. RBF achieves a mean absolute error relative to the CFD model of only 0.54% and the error of the SVR predictions relative to the real data, with scatter, was 12%, compared to 16% from Jensen. This approach has the potential to be used in more complex situations where an existing analytical method is either insufficient or unable to make a good prediction. • A method for stochastic expansion of computational fluid dynamics (CFD) results is developed. • Five machine learning approaches are compared in their approximation of the model results. • Results show that the CFD results can be accurately replicated but are limited by the CFD model. • This approach can be useful for wind farm site wind load evaluation. [ABSTRACT FROM AUTHOR]

• ONRAB® is used to control sylvatic rabies. • ONRAB® vaccine DNA was not detected in wildlife after 34 days post instillation. • Oral instillation resulted in high levels of seropositivity, except in wild caught rats. • Our findings suggest low risk to wildlife populations exposed to ONRAB®. ONRAB® is a human adenovirus rabies glycoprotein recombinant vaccine developed to control rabies in wildlife. To support licensing and widespread use of the vaccine, safety studies are needed to assess its potential residual impact on wildlife populations. We examined the persistence of the ONRAB® vaccine virus in captive rabies vector and non-target mammals. This research complements work on important rabies vector species (raccoon, striped skunk, and red fox) but also adds to previous findings with the addition of some non-target species (Virginia opossum, Norway rats, and cotton rats) and a prolonged period of post vaccination monitoring (41 days). Animals were directly inoculated orally with the vaccine and vaccine shedding was monitored using quantitative real-time PCR applied to oral and rectal swabs. ONRAB® DNA was detected in both oral and rectal swabs from 6 h to 3 days post-inoculation in most animals, followed by a resurgence of shedding between days 17 and 34 in some species. Overall, the duration over which ONRAB® DNA was detectable was shorter for non-target mammals, and by day 41, no animal had detectable DNA in either oral or rectal swabs. All target species, as well as cotton rats and laboratory-bred Norway rats, developed robust humoral immune responses as measured by competitive ELISA, with all individuals being seropositive at day 31. Similarly, opossums showed good response (89% seropositive; 8/9), whereas only one of nine wild caught Norway rats was seropositive at day 31. These results support findings of other safety studies suggesting that ONRAB® does not persist in vector and non-target mammals exposed to the vaccine. As such, we interpret these data to reflect a low risk of adverse effects to wild populations following distribution of ONRAB® to control sylvatic rabies. [ABSTRACT FROM AUTHOR]

Abstract Glass structures are often used in industries utilising large structural topologies. These structures are typically manufactured by post-curing subcomponents together, using a chopped strand mat layer at the interface. To predict failure of these joints requires an accurate assessment of the material and fracture properties. In this paper two industrially manufactured top-hat stiffened panels are tested to determine the fracture behaviour at the component level. This highlights that the variability seen in fracture properties at coupon level is less evident in structural component response. Then a previously developed set of material properties is used to accurately model the structural response, crack initiation and debonding of the panels under four point bend using Finite Element Analysis which gives final failure at 6.2 kN and a 4.4% error compared to the experimental results which exhibits final failure at 5.94 kN. The specific fracture properties tested and R curve are shown to be critical in assessing crack initiation and propagation with considerable error, 14.5%, provided by data assumed from the literature. [ABSTRACT FROM AUTHOR]

Abstract Flax composites demonstrate superior damping properties to conventional fibres. These materials are already being utilised in some products but the mechanical properties they exhibit are too low for many structural applications. Hybridization of flax with higher strength fibres has been shown to yield materials, which balance damping and load carrying capabilities alongside improved environmental credentials for flax/carbon hybrids. However, the most used composite material is E-glass but the current literature does not facilitate the prediction of damping properties for these hybrid composites, where it is expected that they will behave differently due to the difference in material properties. The woven flax and E-glass fibres specimens embedded with epoxy resin are manufactured via resin infusion to understand the damping and mechanical properties possible from an industrial process and the dominant factors affecting them, rather than the relationships between individual variables and these properties. These experiments allow the hybrids to be profiled for the first time and it is observed that hybridization of flax and E-glass fibres results in an increase in damping, from 1.97% to 2.63% for the best hybrid, especially when the flax plies are placed on the outer skin, however the compromise in tensile properties is significant, from 473.28 MPa to 166.53 MPa. [ABSTRACT FROM AUTHOR]

Abstract There are currently over 100,000 merchant ships operating globally. To reduce emissions requires predicting and benchmarking the power they use. This is relatively straightforward for calm conditions but becomes almost impossible in larger waves. Design power predictions for ships in weather are typically derived by applying a 'margin' onto a reference 'calm water power'. This is of questionable accuracy as the techniques available to estimate these 'margins' are inaccurate. To improve the accuracy and flexibility of such predictions this paper investigates the use of neural networks. For this, 27 months of continuous monitoring data are used from 3 vessels of the same design, sampled every 5 min. Multiple network sizes are considered and evaluated to determine the quantity and quality of data required for predictions. A key aspect is determining network architectures optimised not just for accuracy, but that give close relationships between the input variables and shaft power. Predictions are compared to the results of a regression, the conventional tool to determine shaft power from measured full-scale data from ships. The predictions from this network are similar in accuracy to those of standard practices, with an error less than 10%, but the scope for further improvements is large. Highlights • Predicting powering for merchant ships is relatively easy for calm conditions but becomes almost impossible in conditions with larger waves. • To improve this prediction, the use of neural networks has been investigated for large merchant ships. • Network architectures optimised to give close relationships between the input variables and shaft power, not just for prediction accuracy. • The ability of the network to replicate the physics of the problem has been investigated, concluding more research is necessary. • Predictions from this network are similar in accuracy to the standard practises but the scope for further improvements is large. [ABSTRACT FROM AUTHOR]

Glass fibres are a popular choice of material for large structural applications. However, a consistent set of mechanical and interface properties for glass vinylester woven roving is missing from the literature. To predict failure more accurately this paper fully characterises glass composite material, including developing a model for the non-linearity of the woven roving in tension and shear. The mode I and mode II fracture properties for co-cured and post-cured joints are assessed and compared providing a full characterisation of typical materials with a complete data set for both co-cured interfaces, typical of mid-laminate debonds, and post-cured interfaces, typical of sub-component joints. [ABSTRACT FROM AUTHOR]

Due to environmental challenges it is important to investigate potentially more sustainable new materials, including natural fibre reinforced composites. Whilst a number of natural reinforcements show promise there is a concern that laminate properties are too difficult to predict due to the lack of uniformity in natural fibres. The paper quantitatively evaluates the high variability observed at yarn scale, at cloth scale, which shows significant decreases, and at laminate scale, showing comparable variability to synthetic based composites. This demonstrates that natural fibre reinforced composites have reproducible properties at the macroscale level and provides a pathway to application in industry. [ABSTRACT FROM AUTHOR]

Summary Background and aim When observing new faces, most people focus their attention on the central triangle of the face containing the eyes, nose and mouth. When viewing faces with prominent ears, observers may divert their attention from the central triangle. The objective of this study was to determine whether there was an objective attentional bias to prominent ears in comparison to non-prominent ears. Methods A total of 24 naïve participants (13 female; mean age 22.88 years) viewed 15 photographs of children with bilateral prominent ears, unilateral prominent ears and non-prominent ears. Both pre- and post-otoplasty photographs of two patients were included. The eye movements of participants were recorded using the EyeLink 1000, a table-mounted eye-tracking device. Results Overall, the participants spent more time looking at the ear regions for faces with prominent ears in comparison to faces without prominent ears ( p = 0.007, Z = −2.688). The attentional bias to the ear region of the patient who underwent bilateral otoplasty was significantly reduced in the post-operative photograph ( p = 0.011, Z = −2.534). The patient who underwent unilateral otoplasty had no significant change in fixation times towards the ear region ( p = 0.594, Z = −0.533). Conclusions This study presents objective data to support the notion that observers show attentional bias to the ear region when viewing faces of children with prominent ears. The scope of this finding requires further research in both extent and impact. [ABSTRACT FROM AUTHOR]

Top-hat stiffened plates provide an efficient structure for engineering applications. During service debonding between the stiffener and the plate is often observed and parametric studies of open section stiffeners have shown that debond size and location have a significant effect on the damage mode of the panel. However, these studies do not consider the interaction of failure modes and do not assess the ultimate failure of the structure. In this paper top-hat stiffened composite structures are assessed considering debond damage between the stiffener and plate. A non-linear finite element model is used to perform a parametric study on the effect of both damage and the panel’s geometry on the failure modes, ultimate strength and its damage tolerance. Results show that top-hat stiffened panels exhibit a trend between ultimate strength and the debond size with crack initiation not necessarily propagating. Geometric imperfections accelerate buckling but can provide an arrest point for crack propagation. [ABSTRACT FROM AUTHOR]

Danger molecules are the first signals released from dying tissue after stroke. These danger signals bind to receptors on immune cells that will result in their activation and the release of inflammatory and neurotoxic mediators, resulting in amplification of the immune response and subsequent enlargement of the damaged brain volume. The release of danger signals is a central event that leads to a multitude of signals and cascades in the affected and neighbouring tissue, therefore providing a potential target for therapy. [ABSTRACT FROM AUTHOR]

Across many industries damage events leading to a breach in structural integrity continue to occur. An area where this can lead to particularly unsafe conditions is in the maritime environment, where it may be difficult to rescue crew and cargo. In order to improve structural safety through design for the survivability or to assess the residual strength of a damaged vessel in an emergency response or salvage scenario, it is critical to understand the influence of the damage. This paper, for the first time, investigates the use of FEA on ultimate collapse strength of damaged steel grillages and the influence of the damage aperture on the developing failure modes within the structure. The study finds that the presence of damage, in the form of a hole, can lead to the failure mode changing as damage aperture size is increased leading to significant changes to the ultimate collapse strength of the structure. It concludes that to assess the damaged strength of steel plated structures, it is critical that modelling methods are able to capture and account for such mode changes in order to accurately assess the true residual strength of the structure. [ABSTRACT FROM AUTHOR]

After damage rapid and accurate guidance is necessary to safely recover vessels. An improvement in the understanding of ship behaviour after damage will increase chances of recovery of the vessel and safety for the ship crew and cargo, with corresponding benefits to the maritime environment. Whilst a number of studies have investigated static behaviour of damaged ships with permeability previous research at forward speed considers the damaged compartment to be empty. Novel aspects of this research include the study of a variety of permeabilities and internal arrangements of the damaged compartment for a ship moving in waves. Results from experiments carried out in a towing tank using a segmented ship model show that permeability appears to have a large effect on the pitch and heave motion responses when the vessel is travelling at forward speed, with reduced effect for a stationary ship. Furthermore, results indicate that internal arrangement of compartments has less effect than compartment permeability on the damaged ship responses. Finally, the influence of damaged orifice size on the motion responses is investigated and the results show that at forward speed the responses are significantly affected and that they are largest for the minimum orifice size tested. [ABSTRACT FROM AUTHOR]

NADPH oxidases (NOXs) are reactive oxygen species (ROS)-generating enzymes implicated in the pathophysiology of vascular diseases such as hypertension and stroke. Endothelial cells express four NOX isoforms including the superoxide-generating enzymes NOX1, NOX2, and NOX5 and the hydrogen peroxide-generating enzyme NOX4. Studies on arteries from patients with coronary artery disease, and in animals with experimentally induced hypertension, diabetes, or atherosclerosis, suggest that NOX1, NOX2, and NOX5 promote endothelial dysfunction, inflammation, and apoptosis in the vessel wall, whereas NOX4 is by contrast vasoprotective in increasing nitric oxide bioavailability and suppressing cell death pathways. Based on these findings and promising preclinical studies with the NOX1/NOX2 antagonist, apocynin, we suggest that the field is poised for clinical evaluation of NOX inhibitors as therapeutics for cardiovascular disease. [ABSTRACT FROM AUTHOR]

• For the first time a 5-objective optimisation is compared to a 3- and 2- objective optimisation. • The 5-objective optimisation contains solutions that are not in the 3- or 2- objective Pareto Sets. • Genetic Algorithm selection is shown to be important, with cMLSGA shown to be the strongest solver. • 101 fabrics improve performance on all the five objectives compared to a current design. • 77% improvements in mechanical properties and 38% lower densities are possible. Plain weave fabrics provide low-cost composites used in many applications. Their mechanical properties are dependent on the weave and the yarn dimensions, which provides a complex design space to ensure optimal properties for a given application. Genetic Algorithms are commonly used in the literature to optimise the performance of composite materials but are currently limited to two or three objectives, where the optimisation may improve the specified properties but degrade others. In this paper 9 top performing Genetic Algorithms are benchmarked to find designs that respectively satisfy five-objective, three-objective and bi-objective formulations. The results show that the consideration of the five-objective problem is important, since the designs for the five-objective formulation give a wider range of results. These results do not include designs from the optimisation with the more limited objectives, meaning that these designs would need to be redesigned to be practical and demonstrating the benefits of optimisation with more objectives. cMLSGA is shown to be the strongest solver for these problems, contradicting the findings from the Evolutionary Computation literature. When compared with a current weave pattern, the five-objective optimisation provides 101 designs which improve all 5 material properties, with up to 76.61% improvements on the four mechanical properties and a maximum 37.73% reduction on areal density; there are weave patterns with designs that are specific to each of the properties individually. [ABSTRACT FROM AUTHOR]

Abstract: The design process is becoming increasingly complex with designers balancing societal, environmental and political issues. Composite materials are attractive to designers due to excellent strength to weight ratio, low corrosion and ability to be tailored to the application. One problem with composite materials can be the low stiffness that they exhibit and as such for many applications they are stiffened. These stiffened structures create a complex engineering problem by which they must be designed to have the lowest cost and mass and yet withstand loads. This paper therefore examines the way in which rapid assessment of stiffened boat structures can be performed for the concept design stage. Navier grillage method is combined with genetic algorithms to produce panels optimised for mass and cost. These models are constrained using design rules, in this case ISO 12215 and Lloyd's Register Rules for Special Service Craft. The results show a method that produces a reasonable stiffened structure rapidly that could be used in advanced concept design or early detailed design to reduce design time. [Copyright &y& Elsevier]

Highlights: [•] ONRAB is a recombinant human adenovirus vaccine developed to control sylvatic rabies. [•] The safety and effectiveness of ONRAB requires further investigation prior to widespread use. [•] We studied persistence and shedding of ONRAB in wild mammals with quantitative PCR. [•] No samples contained amounts of ONRAB DNA that exceeded the quantification limit. [•] Our results suggest a short replication period of ONRAB and a low risk of spread. [ABSTRACT FROM AUTHOR]

Abstract: Composite materials are often utilised for their high strength to weight ratio, excellent corrosion resistance, etc. but are also characterised by variabilities and uncertainties in their mechanical properties owing to the material make-up, process and fabrication techniques. It is essential that modelling techniques continue to be developed to take account of these variabilities and uncertainties and as more complicated structures are developed it is important to have rapid assessment methods to determine the reliability of these structures. Grillage analysis methods have been previously used for assessment of tophat stiffened composite structures using simple failure criteria. As new criteria are introduced, such as by the World Wide Failure Exercise, the response of more complex topologies must be introduced. This paper therefore assesses the reliability of composite grillages using Navier grillage method incorporating up to date failure criteria. An example, taken from boatbuilding, is used to show the results of using these more complex assessment methods showing that it is of high importance to use the correct assessment criteria. [Copyright &y& Elsevier]

Abstract: In an unpredictable world where human intervention or unexpected environmental conditions can prevail, damage can occur to manmade structures. Whilst structural design allows for redundancy, or a structural capability beyond the general working load of the structure, it is necessary to be able to analyse and understand the residual capability of a damaged structure to ensure the safety of personnel in the vicinity of the structure and assess the potential to facilitate repair. Idealised Structural Unit Method (ISUM) can allow rapid assessment of large structural arrangements by simplification into smaller constituent parts, which are assessed against pre-calculated failure data for each part. The method has potential benefits for allowing rapid assessment of damaged steel-plated structure that would otherwise require the use of high fidelity modelling of the entire structures, such as through the use of finite element analysis. This paper presents a study on the use of ISUM to assess damaged steel-plated structures and its limitations through the collapse analysis of stiffened steel panels. A new ISUM is proposed for strength assessment of damaged structural arrangements. Analysis is undertaken to assess the effects of geometrical and material property variations that can occur in a structure as well as the effects of damage aperture size and shape on the collapse strength of stiffened steel panels. The study shows that while ISUM can be applied in the assessment of damaged steel-plated structures, implementing the proposed new ISUM allows greater accuracy in the calculation of the collapse strength of damaged stiffened steel panels. The paper also concludes that the assessment of larger structural units for application in the ISUM assessment, will allow the effects of the damage on surrounding structure to be captured, which can influence the deflection shapes that will lead to collapse of the structure. [Copyright &y& Elsevier]

Abstract: Until the 1970s, reactive oxygen species (ROS) were considered merely harmful by-products of aerobic respiration and the driving force behind the evolution of an array of cellular antioxidant enzymes with the purpose of rapidly metabolising ROS to minimise their oxidising effects. However, the perception that ROS are only harmful to cells has since been questioned by a burgeoning body of evidence pointing to the existence of enzymes with the dedicated function of generating ROS. NADPH oxidases represent the only known family of enzymes whose sole purpose is to generate ROS. Members of this enzyme family are expressed across mammalian and non-mammalian cells, and influence a multitude of biological functions including host defence and redox signalling. However, although ROS are deliberately generated by NADPH oxidases during normal cell physiology, the observations that their expression and activity is markedly upregulated in the blood vessel wall in a number of cardiovascular ‘high-risk’ states (e.g. hypertension, hypercholesterolemia) implicates them in the oxidative stress that gives rise to artery disease and ultimately heart attacks and strokes. These observations highlight the fact that NADPH oxidases are important therapeutic targets in cardiovascular disease and that, hence, there is clearly a need for the development of selective inhibitors of these enzymes. Here we highlight the structural and biochemical characteristics of the NADPH oxidase family and then comprehensively review the literature on the currently available pharmacological inhibitors of these enzymes with a particular emphasis on their mechanisms of action, isoform selectivity and therapeutic potential in cardiovascular disease. [Copyright &y& Elsevier]

The use of Hamilton’s Principle in determining the governing partial differential equations of motion for such problems as the free vibration of complex elastodynamic systems has been known for many years, but the implementation of the integration procedure using symbolic computation does not appear to have been solved. In this paper we present the application of a computer algebra package called REDUCE that takes away the human cost. We show the use of this package in a simple example, and for a twisted beam such as an idealised helicopter blade. [Copyright &y& Elsevier]

DNA is not only in the focus of modern molecular biology, but also plays an increasingly important role as a building block for nanoscale materials and devices. In recent years, many researchers in nanoscience have used the unique, programmable molecular recognition properties of DNA to build nanostructures by self-assembly and to realize artificial, machine-like devices. We here give a brief survey of this field and discuss the possible applications of DNA-based nanodevices either as nanoscale motors and actuators, or as novel biosensors with built-in information-processing capability. [Copyright &y& Elsevier]

Hypertension is a major public health challenge because of its high frequency and associated cardiovascular risk. Accumulating evidence suggests that reactive oxygen species derived from NADPH-oxidase play a pivotal role in vascular damage associated with hypertension. The clinical benefits of three of the most prescribed classes of cardiovascular drugs might all indirectly involve inhibition of NADPH-oxidase. Thus, development of inhibitors of vascular isoforms of NADPH-oxidase could have substantial benefit in the treatment of hypertension. [Copyright &y& Elsevier]

Abstract: A dynamic stiffness theory of a three-layered sandwich beam is developed and subsequently used to investigate its free vibration characteristics. This is based on an imposed displacement field so that the top and bottom layers behave like Rayleigh beams, whilst the central layer behaves like a Timoshenko beam. Using Hamilton’s principle the governing differential equations of motion of the sandwich beam are derived for the general case when the properties of each layer are dissimilar. For harmonic oscillation the solutions of these equations are found in exact analytical form, taking full advantage of the application of symbolic computation, which has also been used to obtain the amplitudes of axial force, shear force and bending moment in explicit analytical forms. The boundary conditions for responses and loads at both ends of the freely vibrating sandwich beam are then imposed to formulate the dynamic stiffness matrix, which relates harmonically varying loads to harmonically varying responses at the ends. Using the Wittrick–Williams algorithm the natural frequencies and mode shapes of some representative problems are obtained and discussed. The important degenerate case of a symmetric sandwich beam is also investigated. [Copyright &y& Elsevier]

Our understanding about the behaviour of numerical solutions for evolutionary convection–diffusion equations is mainly based on analysis of infinite domains situations with stability given by von Neumann analysis. Almost all practical problems involve physical domains with boundaries. For evolution problems with Dirichlet boundary conditions, some algorithms can be used without alteration near a boundary. However, the application of higher order methods such as Quickest or second order upwinding introduces difficulty near an inflow boundary, since for interior points adjacent to the boundary there are insufficient upstream points for the high order scheme to be applied without alteration. For that reason such methods require a careful treatment on the inflow boundary, where additional numerical boundary conditions have to be introduced. The choice of numerical boundary conditions turns out to be crucial for stability. A test problem is described, showing the practical advantages of some numerical boundary conditions versus the others by comparison with an exact solution. [Copyright &y& Elsevier]

[Display omitted] • Develop a new artificial neural network-based data fusion model to provide tailored corrosion predictions for bulk carriers. • Combine operational information from ship surveys and corrosion fundamentals from experimental measurements. • Prediction accuracy is improved by at least 82% compared to the state-of-the-art corrosion models. • The model quantifies the contribution of different environmental/operating factors to the marine corrosion of carbon steels. Accurate corrosion predictions are vital to safe and optimised designs of marine assets. Traditional approaches, including those used to develop rule requirements, seek to use empirical regressions to model corrosion, but most are solely time-dependent. This may lead to conservative damage estimates and hence heavy and inefficient ships. To provide more accurate predictions, this paper presents an interpretable machine learning algorithm based on data fusion of ship survey and experimental measurements. The corrosion behaviour in bulk carrier ballast tanks is interpreted through a sensitivity analysis which quantifies the relationships between operational/environmental factors and the corrosion rate. The prediction accuracy is improved by a minimum of 82% when compared to the two representative empirical models, with a mean absolute error down to 0.10 mm. [ABSTRACT FROM AUTHOR]

The change from steel risers to composites comes with uncertainties that led to large safety factors. One area of uncertainty is the predicted response and stresses derived from commercial packages that are based on formulations that assume in-extensible riser. However, composite pipes exhibit a lower axial stiffness and therefore the velocity of the axial waves will change with a corresponding change in dynamic response. To determine the effect of this assumption, this paper assesses the effect of extensibility on the time-domain response. It is found that the in-extensible model predicts 3 times the number of high frequency tension cycles in the 20 kN tension range. To determine the impact of this change on the stress, the accuracy of available composite pipe models is benchmarked using shell, continuum-shell and solid elements. The quadratic and continuum-shell elements provide a maximum percentage difference of 4% compared to solid elements but the continuum-shell is selected as it has a lower computational cost. The response from the extensible and in-extensible models are input into the pipe model, they provide similar Tsai-Wu failure factors, alleviating concerns when modelling the strength. However, the change in dynamics remains a concern for other applications such as machine-learning or digital-twins. • Extensible and in-extensible beam models are investigated with composite risers. • In-extensibility causes spurious oscillations, affecting the riser predicted tension. • Quadratic S8R, and continuum shell elements SC8R are optimum to model the composite pipe. • A coupled in-extensible beam predicts failure factors higher than the extensible equivalent. [ABSTRACT FROM AUTHOR]

The task of providing optimal composite structures is increasingly difficult. New analysis approaches seek to model the material at the fibre/matrix scale and increasingly more control is sought over the material, for example optimising individual tows, and the structure, where new manufacturing techniques are proposed that will allow revolutionary new topologies. This additional complexity will stretch design engineers and as such it is important that state-of-the-art design methods are implemented to help take advantage of these exciting new opportunities, including computational optimisation methods. To determine best practice and the current limitations of the techniques a review of Genetic Algorithms in optimisation of composite materials and structures is performed over the last 10 years. This is compared to a technical review of the developments of Genetic Algorithms in the evolutionary computation literature. By better understanding how Genetic Algorithms are used in composite structures and comparing to evolutionary computational literature, recommendations are provided to help increase the use of Genetic Algorithms in solving composite optimisation problems in the future. [ABSTRACT FROM AUTHOR]

Flax fibres are often documented as having equivalent properties to E-glass ones. Based on these comparisons they have been proposed as a suitable replacement for E-glass in structural applications. However, some recent experimental studies demonstrate that flax behaves differently to conventional composites at the structural scale, which indicates that the capabilities of flax need to be better understood at this scale. This paper therefore uses reliability analysis to generate flax structures with an equivalent safety to those in E-glass, accounting for the change in behaviour. An extensive literature review of flax laminate mechanical properties is performed to define their range and variations. These values are used to simulate probabilities of failure which demonstrate that flax structure needs to be 2.4 times heavier than the E-glass structures to have an equivalent safety. It concludes that flax fibres might be used in some applications but cannot replace E-glass in volume constrained structures. [ABSTRACT FROM AUTHOR]

Traditional mooring systems can be unsuitable and uneconomical for floating offshore wind turbines. Load reduction devices, which are extensible components installed along mooring lines, have been shown to reduce loads on anchors and mooring lines. This enables the use of smaller and lighter anchors and mooring components and reduces fatigue damage on the mooring system. Load reduction devices come in various forms, including ballasted pendulums, polymer springs, and hydraulic dampers, each with unique non-linear stiffness curves. These non-linear curves typically consist of either a progressively-increasing 'single-phase' stiffness, or a 'three-phase' stiffness which exhibit stiff first and third-phase responses with a low-stiffness second phase. Selecting the correct shape of stiffness curve is key to ensure optimal load reduction performance from the device. This study compares the impact of 4 different non-linear stiffness curves, including 2 single-phase curves and 2 three-phase curves, on tension reduction and platform motions through finite element modelling. Taut and catenary mooring configurations, in both shallow (75 m) and intermediate (150 m) water depths, during 50-year parked and 50-year operational load cases are considered. The IEA 15 MW reference turbine, on the reference Voluturn-US semi-submersible platform are adopted for the analyses. Of the 4 non-linear stiffness curves considered, those with three-phase stiffness offer the maximum load reduction compared to a base mooring with no load reduction device, and are most effective in reducing fatigue damage. All load reduction device stiffness curve types have little effect on out-of-plane motions of the platform and acceleration at the nacelle, but lead to an increase in horizontal offset, or surge, of the floating offshore wind turbine when compared to the base mooring system. The increase in surge is similar regardless of the load reduction device stiffness curve shape, and is shown to be mainly driven by the length and rated tension of the device. • Numerical modelling of taut and catenary mooring systems with load reduction devices. • Various non-linear load reduction device (LRD) stiffness curves are compared. • All LRD stiffness curves provide highest benefit in shallow water and taut moorings. • 3-phase stiffness curves provide the most peak tension and fatigue damage reduction. • Wind-induced platform surge is increased by LRDs, wave-induced motions are reduced. [ABSTRACT FROM AUTHOR]

Stroke accounts for more than 10% of deaths worldwide, and over a third of survivors are left with major neurological impairment. The need for new and effective therapies for stroke is therefore clear and urgent. While some advances have been made toward understanding its mechanisms, still only one pharmacological intervention has been found to reduce brain injury following clinical stroke – the ‘clot-buster’ recombinant tissue plasminogen activator. Unfortunately however, with a short time window of only 4.5 h, this therapy is available to less than 10% of stroke patients. For further advances in the clinical treatment of ischemic stroke, the complex mechanisms of cellular injury following cerebral ischemia must be elucidated to provide novel targets for future therapies. The initial ischemic insult is now known to be followed by induction of cytokines and chemokines, which attract numerous inflammatory cell types to the damaged brain region and ultimately contribute to secondary brain injury. Neutrophils, monocytes, T and B lymphocytes may each become activated, infiltrate the brain and modulate the severity of stroke outcome. This presentation will describe some of our recent work targeting various immune cell mechanisms for novel therapies in experimental acute stroke. [ABSTRACT FROM AUTHOR]

Stroke is responsible for almost 6 million deaths and more than 10% of all mortalities each year, and two-thirds of stroke survivors remain disabled. With treatments for ischemic stroke still limited to clot lysis and/or mechanical removal, new therapeutic targets are desperately needed. In this review, we provide an overview of the complex mechanisms of innate and adaptive immune cell-mediated inflammatory injury, that exacerbates infarct development for several days after stroke. We also highlight the features of poststroke systemic immunodepression that commonly leads to infections and some mortalities, and argue that safe and effective therapies will need to balance pro- and anti-inflammatory mechanisms in a time-sensitive manner, to maximize the likelihood of an improved long-term outcome. Stroke is the leading cause of death and disability globally. Two-thirds of stroke survivors are left disabled, requiring assistance in daily living tasks. Currently, treatments for ischemic stroke are limited to clot lysis and/or mechanical removal within a few hours of stroke onset. In addition to the brain injury and cell death that occurs rapidly due to severe cerebral ischemia, a secondary phase of infarct growth is driven by inflammation for several days. There are complex contributions from the innate and adaptive immune systems, but an improved understanding of this process may yield new therapeutic targets to limit stroke injury. [ABSTRACT FROM AUTHOR]

Increasingly, autonomous agents will be required to operate on long-term missions. This will create a demand for general intelligence because feedback from a human operator may be sparse and delayed, and because not all behaviours can be prescribed. Deep neural networks and reinforcement learning methods can be applied in such environments but their fixed updating routines imply an inductive bias in learning spatio-temporal patterns, meaning some environments will be unsolvable. To address this problem, this paper proposes active adaptive perception, the ability of an architecture to learn when and how to modify and selectively utilise its perception module. To achieve this, a generic architecture based on a self-modifying policy (SMP) is proposed, and implemented using Incremental Self-improvement with the Success Story Algorithm. The architecture contrasts to deep reinforcement learning systems which follow fixed training strategies and earlier SMP studies which for perception relied either entirely on the working memory or on untrainable active perception instructions. One computationally cheap and one more expensive implementation are presented and compared to DRQN, an off-policy deep reinforcement learner using experience replay and Incremental Self-improvement, an SMP, on various non-episodic partially observable mazes. The results show that the simple instruction set leads to emergent strategies to avoid detracting corridors and rooms, and that the expensive implementation allows selectively ignoring perception where it is inaccurate. [ABSTRACT FROM AUTHOR]

Abstract Natural fibres exhibit improved sustainability and similar mechanical properties to E-glass. However, for laminates there is a larger difference in properties and limited assessments of structural components. An analytical method for grillages is developed which is generally shown to predict the stress to within 5% of an FEA model. The simulations demonstrate a change in structural response between flax and carbon, with flax demonstrating higher stresses than expected for the lower Young's modulus for the same topology. Flax is shown to be more sensitive to transverse Young's modulus than standard composites and a better characterisation of this property is required. [ABSTRACT FROM AUTHOR]

Abstract: Vascular Ehlers–Danlos Syndrome (EDS) is a rare autosomal dominant condition resulting from a defect in type III procollagen synthesis. This causes the development of severe vascular pathologies, including arterial rupture and pseudoaneurysm formation. We present a case of a young boy previously diagnosed with vascular EDS due to a Gly975Val substitution in the collagen α1(III) chain presenting with a common femoral artery dissection secondary to minimal trauma. This was managed conservatively with serial duplex scans and gentle mobilization. At follow up the patient had returned to normal activities, with MRA and duplex scans showing complete resolution of the dissection. [Copyright &y& Elsevier]