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Alpha-pinene is a monoterpene found in the oil of coniferous trees and has a wide variety of applications. Alpha-pinene oxide (APO) is a potential reactive metabolite of alpha-pinene in rodents. The objective of this work is to validate a gas chromatography–mass spectrometry method to quantitate APO in rat and mouse blood and mammary glands in support of studies investigating the toxicity and toxicokinetic behavior of alpha-pinene. The method was validated in male Sprague Dawley rat blood over the concentration range of 5–250 ng/mL. Matrix standard curves were linear (r ≥ 0.99), and accuracy (percent relative error, %RE) was ≤±15% for standards at all levels. Intra- and interday precision (percent relative standard deviation, %RSD) and accuracy (%RE) were evaluated at three concentration levels (10, 50 and 200 ng/mL) and were ≤6.3% and ≤±5.4%, respectively. The limit of detection, determined from the SD of the limit of quantitation (5 ng/mL), was 1.06 ng/mL. Standards as high as 25,000 ng/mL could be accurately quantified after diluting to the validated range (%RE ≤ ±7.1%; %RSD ≤ 5.8%). APO was stable in rat blood for at least 70 days in frozen storage (−80°C). APO could accurately be quantified in male and female Hsd:Sprague Dawley® SD® rat and B6C3F1 mouse blood (mean %RE ≤ ±5.3%; %RSD ≤ 7.8%) and female B6C3F1 and Sprague Dawley rat mammary glands (mean %RE ≤ ±14.6%; %RSD ≤ 8.1%) using a primary matrix standard curve. These results demonstrate that the method is suitable for the analysis of APO in rodent blood and mammary glands generated from toxicokinetic and toxicology studies.

The COSMOS-UK observation network has been providing field scale soil moisture and hydrometeorological measurements across the UK since 2013. At the time of publication a total of 51 COSMOS-UK sites have been established, each delivering high temporal resolution data in near-real time. Each site utilises a cosmic-ray neutron sensor, which counts fast neutrons at the land surface. These measurements are used to derive field scale near-surface soil water content, which can provide unique insight for science, industry, and agriculture by filling a scale gap between localised point soil moisture and large-scale satellite soil moisture datasets. Additional soil physics and meteorological measurements are made by the COSMOS-UK network including precipitation, air temperature, relative humidity, barometric pressure, soil heat flux, wind speed and direction, and components of incoming and outgoing radiation. These near-real time observational data can be used to improve the performance of hydrological models, validate remote sensing products, improve hydro-meteorological forecasting and underpin applications across a range of other scientific fields. The most recent version of the COSMOS-UK dataset is publically available at https://doi.org/10.5285/37702a54-b7a4-40ff-b62e-d14b161b69ca (Stanley et al., 2020).

While Medieval Studies is a global discipline with experts spread across the world, academics and general audiences in the Global North are often unaware of the research and projects undertaken by their counterparts in the Global South. In this interview, James Blake Wiener speaks to Dr. Gimena del Rio Riande who works as a researcher with the Institute of Bibliographic Research and Textual Criticism at the National Scientific and Technical Research Council (CONICET) in Buenos Aires, Argentina. Gimena is a tireless advocate for medieval studies across Latin America and for the digital humanities as an open field of research.

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.

Weather routing methods are essential for planning routes for commercial shipping and recreational craft. This paper provides a methodology for quantifying the significance of numerical error and performance model uncertainty on the predictions returned from a weather routing algorithm. The numerical error of the routing algorithm is estimated by solving the optimum path over different discretizations of the environment. The uncertainty associated with the performance model is linearly varied in order to quantify its significance. The methodology is applied to a sailing craft routing problem: the prediction of the voyaging time for an ethnographic voyaging canoe across long distance voyages in Polynesia. We find that the average numerical error is $0.396\%$, corresponding to $1.05$ hours for an average voyage length of $266.40$ hours. An uncertainty level of $2.5 \%$ in the performance model is seen to correspond to a standard deviation of $\pm 2.41-3.08\%$ of the voyaging time. These results illustrate the significance of considering the influence of numerical error and performance uncertainty when performing a weather routing study.

On 21 April 2013, during a co-ordinated Saturn auroral observing campaign, the northern and southern poles of the planet were observed from the Earth using the NASA Infrared Telescope Facility (IRTF), Keck, and Hubble Space Telescope (HST) simultaneously with the Cassini infrared, visible, and ultraviolet remote sensing instruments. We present simultaneous multi-scale and multi-wavelength analysis of the morphology of auroral emissions at Saturn. The visible main auroral emission vary between ∼∼2 and 10 kR on timescales of minutes and across spatial scales of down to ∼∼14 km on the planet. The H2 Far Ultraviolet (FUV) brightness varies by a factor of ∼∼10, from ∼∼4–40 kR, over timescales of 1 min and spatial scales of 720 km. View the MathML sourceH3+ infrared emissions vary less than the H2 emissions, from ∼∼5–10 μμW m−2 sr−1, over similar spatial scales (∼∼300 km) and timescales of a few seconds to a few hours. The fine-scale temporal and spatial features seen in the main oval show that complex structures are present even during quiet solar wind conditions. Diffuse ultraviolet emissions southward of the southern midnight main oval that are not seen in the infrared, implying a steep temperature gradient of ∼∼50 K over 2–4°° latitude equatorward of the main oval. Dynamics on scales of ∼∼100 km at the poles are revealed by lower spatial resolution observations, the morphologies of which are partly consistent with overlapping local-time fixed and co-rotating current systems. We also present the first direct comparison of simultaneous infrared, visible, and ultraviolet auroral emissions at Saturn. Finally, the main auroral emissions are found to be approximately co-located in the midnight sector, forming an arc with a width of ∼∼0.5–1°°, at 72–74° southern latitude, moving slightly equatorward with increasing local-time.

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.

Some species of fish are able to alter their mode of swimming to interact with naturally produced vortices; the use of these gaits reduces the energy expended by the fish. To analyse the feasibility of autonomous underwater vehicles replicating these gaits, a series of experiments are performed with unpowered rigid and flexible bodies positioned in the Kármán wake of a rigid cylinder. Simple motion capture techniques are used to capture the bodies’ lateral and upstream motion in the flow. The results demonstrate that manufactured bodies are capable of passively mimicking fish behaviours, to a limited extent. More importantly, it was concluded that while significant upstream movement was possible for a manufactured object, it was achievable irrespective of the stiffness of the material. For autonomous underwater vehicles operating in unsteady flow regimes, an ability to utilise energy-saving gaits may improve the range or operational time.

We present the first detailed analysis of H3+ nightside emission from Jupiter, using Visual and Infrared Mapping Spectrometer (VIMS) data from the Cassini flyby in 2000–2001, producing the first Jovian maps of nightside H3+ emission, temperature, and column density. Using these, we identify and characterize regions of H3+ nightside emission, compared against past observations of H3+ emission on the dayside. We focus our investigation on the region previously described as “mid-to-low latitude emission,” the source for which has been controversial. We find that the brightest of this emission is generated at Jovigraphic latitudes similar to the most equatorward extent of the main auroral emission but concentrated at longitudes eastward of this emission. The emission is produced by enhanced H3+ density, with temperatures dropping away in this region. This emission has a loose association with the predicted location of diffuse aurora produced by pitch angle scattering in the north, but not in the south. This emission also lays in the path of subrotating winds flowing from the aurora, suggesting a transport origin. Some differences are seen between dayside and nightside subauroral emissions, with dayside emission extending more equatorward, perhaps caused by the lack of sunlight ionization on the nightside, and unmeasured changes in temperature. Ionospheric temperatures are hotter in the polar region (~1100–1500 K), dropping away toward the equator (as low as 750 K), broadly similar to values on the dayside, highlighting the dominance of auroral effects in the polar region. No equatorial emission is observed, suggesting that very little particle precipitation occurs away from the polar regions.

The present work presents a novel methodology developed for calculating the steady loads acting on aircraft structures in the event of ditching in water. It represents the preliminary result of Stirling Dynamics as part of a NATEP research project. The overall objective of the project is to expand the capabilities of the Stirling Dynamics proprietary software SD-GLOAD (originally designed for ground and crash loads dynamic simulations) to aircraft ditching simulations. The methodology presented in this paper employs a Doublet Lattice Method (DLM) to calculate the steady pressure distribution acting on the submerged parts of the ditching aircraft. The proposed methodology is validated against a higher-fidelity CFD multi-phase model for a selected test-case and several ditching conditions.

Composite materials are increasingly being used within engineering, especially in low weight applications. A significant drawback that these materials exhibit is their variability. There is a growing trend towards stochastic analysis of marine structures and this is even more important for scenarios that have a high variability. To implement these new techniques it is important to be able to, rapidly and accurately, determine reliability during the design phase. Therefore, a reliability analysis, utilising a rapid implementation, has been performed on plates that have been designed using two different sets of design rules and a first principles method. The results show that whilst, under the limits investigated, the reliability of the design rules are slightly safer than those found using first principles; the sensitivity analysis shows that each of the design rules generates a different reaction from each variable, encouraging different types of structures through their idiosyncrasies. Furthermore the method shown allows a rapid analysis to be performed on complex composite structures in a relatively short time frame using either first principles methods or design rules.

Composite materials have been widely used in modern engineering fields such as aircraft, space and marine structures due to their high strength-to-weight and stiffness-to-weight ratios. However, structural efficiency gained through the adoption of composite materials can only be guaranteed by understanding the influence of production upon as-designed performance. In particular, topologies that are challenging to production including panels stiffened with pi or tophat stiffeners dominate many engineering applications and often observe complex loading. The design of stiffened composite panels against buckling is a key point of composite structures. While a growing number of studies are related to the reliability analysis of composites few of these relate to the local analysis of more complicated structures. Furthermore for the assessment of these structures in a design environment it is important to have models that allow the rapid assessment of the reliability of these local structures. This paper explores the use of a stochastic approach to the design of stiffened composite panels for which typical applications can be found in composite ship structures. A parametric study is conducted using Navier grillage theory and First-order Reliability Methods to investigate any detectable trend in the safety index with various design parameters. Finally, recommendations are made to provide guidance on applications.

Grillage topologies are commonly used in many composite structural applications to produce low mass designs that have a high stiffness. While composite failure criteria are being compared in many different simple structures, for example plates and tubes, literature must also compare more complicated applications, including grillages, as there are distinct differences in behaviour. This paper therefore performs analysis of grillage structures with more up to date failure criteria, taken from the world wide failure exercise, than previously investigated. The grillage theory selected is that of Navier theory with elastic equivalent properties due to its low computational expense for use with a genetic algorithm to optimise a composite structure. The results take an example from leisure boatbuilding showing the grillages produced from the different limit states, comparing the cost and mass. The final results show that the method allows a rapid analysis of grillages and that the selection of the limit state has an important effect on the optimised grillage topology.

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.

The leisure boatbuilding industry has tight profit margins that demand that boats are created to a high quality but with low cost. This requirement means reduced design times combined with increased use of design for production can lead to large benefits. The evolutionary nature of the boatbuilding industry can lead to a large usage of previous vessels in new designs. With the increase in automated tools for concurrent engineering within structural design it is important that these tools can reuse this information while subsequently feeding this to designers. The ability to accurately gather this materials and parts data is also a key component to these tools. This paper therefore aims to develop an architecture made up of neural networks and databases to feed information effectively to the designers based on previous design experience., {"references":["H.A. HAGHIAC and I. HAQUE. 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The present paper is a continuation of a memoir read at the Académie des Sciences of Paris, in 1839, and entitled, “Effets de diverses substances salines, injectées dans le systême circulatoire. After some preliminary remarks on the mode in which the experiments were conducted, and on the assistance derived from the hæmadynamometer of Poiseuille (or instrument for measuring the pressure of the blood circulating in the vessels), the author gives a list of the various saline substances of which he noted the effects when they were severally injected either into the venous or the arterial systems, arranged according to the nature of those effects. He finds, in general, that all the salts having the same base exert similar actions when introduced directly into the blood. He carefully inquires into the phænomena apparently arising from the direct contact of each of the substances above enumerated with the animal tissues; and more particularly into the effects produced on the heart, on the muscular and the nervous tissues, and on the pulmonary and systemic capillaries.

The 2016 Paralympic Games in Rio de Janeiro will see 200m sprint canoe events for the first time, using the Va’a class. The aim of this study is to predict race times for the Va’a over a 200m sprint event, through simulation of the hydrodynamic resistance of the hull (with outrigger) and the propulsion provided by the athlete. Such a simulation, once suitably validated, allows investigation of design and configuration changes on predicted race performance. The accuracy of the simulation is discussed through a comparison to times recorded for an athlete over a 200m race distance.