The comparison of knee joint kinematics between two types of stop jump

Sagittal and frontal plane knee kinematics have been linked to anterior cruciate ligament injury risk during several jumping and landing tasks. The purpose of this study was to compare the knee joint kinematics of the dominant and non-dominant leg during two types of stop jump. Eleven recreationally active participants performed a stop jump from an anteroposterior approach and from a mediolateral approach. The study found significant differences in knee flexion for both limbs, and significant between-limb differences in knee flexion for the mediolateral approach and knee varus/valgus for the anteroposterior approach (p<0.05). These findings indicate that both types of stop jump may pose a risk of injury, but particularly during the anteroposterior approach for both limbs, and the mediolateral approach for the non-dominant limb only

Linking arable and livestock farms: Impact of grazing sheep on winter cereals and soil health

Given, in recent years, the UK has experienced a number of extreme weather events, and climate modellers are predicting these to occur more frequently in future, there is concern by some farmers in their ability to reliably provide sufficient homegrown forage for their ruminant livestock, especially over the winter period before grass fields are ready. There is also a desire by some arable farms to include livestock within their system in some way in order to try improving their soil health and in particular levels of residual nitrogen and organic matter through the act of animal manuring and urine deposition. These arable farmers do not necessarily want to change to a fully mixed farming system, or have overall responsibility for the animals involved. The grazing of winter cereals on arable farms by local shepherds / graziers has potential to provide a route to achieve this mutualistically beneficial relationship. This paper is based on a recent series of controlled field experiments and farmer led demonstrations in NE Scotland that have been used to test the hypothesis that the grazing of winter cereals can provide both a valuable late winter feed source for ruminants, as well as maintain acceptable grain and straw yields, while maintaining soil “health”. The overall aim was to assess a number of factors, including how crop establishment timing, grazing timing, intensity and stocking rate impacts on the performance of different winter cereals and the potential for economic and environmental benefits associated with this practice to be achieved.Results to date suggest that winter wheat, winter barley and winter oats can be grazed quite heavily, using either intensive grazing over a short period of time, or less intensive grazing over a longer period of time, without any clear negative impacts on a range of crop (including yield and quality) or soil factors. Analysis of the feed value of these crops at the time grazing has taken place, typically for between a few days and several weeks, within the period late November through to mid-March, has been consistently impressive. <br/

Soil health metrics reflect yields in long‑term cropping system experiments

Soil health metrics with strong links to ecological function and agricultural productivity are needed to ensure that future management of agricultural systems meets sustainability goals. While ecological metrics and crop yields are often considered separately from one another, our work sought to assess the links between the two in an agricultural context where productivity is a key consideration. Here, we investigated the value of soil health tests in terms of their relevance to agricultural management practices and crop yields at contrasting long term cropping systems experiments. One site was on a sandy loam Leptic Podzol and the other on a sandy clay loam Endostagnic Luvisol. Furthermore, the experiments had different management systems. One contained legume-supported rotations with different grass-clover ley durations and organic amendment usage, while the other compared a range of nutrient input options through fertiliser and organic amendments on the same rotation without ley periods. Metrics included field tests (earthworm counts and visual evaluation of soil structure scores) with laboratory analysis of soil structure, chemistry and biology. This analysis included bulk density, macroporosity, pH, available phosphorus, exchangeable potassium, soil organic matter and potentially mineralizable nitrogen. Using a novel combination of long-term experiments, management systems and distinctive soil types, we demonstrated that as well as providing nutrients, agricultural management which resulted in better soil organic matter, pH, potassium and bulk density was correlated with higher crop yields. The importance of ley duration and potentially mineralizable nitrogen to yield in legume-supported systems showed the impact of agricultural management on soil biology. In systems with applications of synthetic fertiliser, earthworm counts and visual evaluation of soil structure scores were correlated with higher yields. We concluded that agricultural management altered yields not just through direct supply of nutrients to crops, but also through the changes in soil health measured by simple metrics

Scallop swimming kinematics and muscle performance: modelling the effects of "within-animal" variation in temperature sensitivity

Escape behaviour was investigated in Queen scallops (Aequipecten opercularis) acclimated to 5, 10 or 15 degrees C and tested at their acclimation temperature. Scallops are active molluscs, able to escape from predators by jet-propelled swimming using a striated muscle working in opposition to an elastic hinge ligament. The first cycle of the escape response was recorded using high-speed video ( 250 Hz) and whole-animal velocity and acceleration determined. Muscle shortening velocity, force and power output were calculated using measurements of valve movement and jet area, and a simple biomechanical model. The average shortening speed of the adductor muscle had a Q(10) of 2.04, significantly reducing the duration of the jetting phase of the cycle with increased temperature. Muscle lengthening velocity and the overall duration of the clap cycle were changed little over the range 5 - 15 degrees C, as these parameters were controlled by the relatively temperature-insensitive, hinge ligament. Improvements in the average power output of the adductor muscle over the first clap cycle ( 222 vs. 139 W kg(-1) wet mass at 15 and 5 degrees C respectively) were not translated into proportional increases in overall swimming velocity, which was only 32% higher at 15 degrees C ( 0.37m s(-1)) than 5 degrees C (0.28 m s(-1))