Bats

Volume: I

The use of a Rotary Asphalt Broom to Groom Aggregate Forest Roads

Due to the dispersed nature of forestry operations in much of the world, only a subset of a given forest road network are used in any year. Specifically, spur roads are generally only used when harvesting operations are adjacent to roadways; otherwise, they remain unused or only have infrequent administrative traffic. During these periods of light use, a substantial amount of organic litter may build up on the roads. As this detritus accumulates and decays, it creates conditions that encourage the growth of unwanted vegetation in the roadway, accelerating the contamination of the surface aggregate. This organic material can degrade the road by retaining moisture and creating a less tractive road surface. Contemporary forest practices control this unwanted vegetation by using a combination of grading or herbicides, at significant expense. One potential alternative treatment is the utilization of a rotary-mounted asphalt broom for vegetation and debris removal. A series of field trials were performed on wet, contaminated forest roads, in which we evaluated vegetation, debris removal effectiveness, and tire slip on segments of road before and after sweeping. The combined effects of wire and synthetic bristles on the rotary broom proved effective in both increasing traction and removing unwanted debris and vegetation from the road surface. Application of this technique was expedient, and did not result in significant loss of surface aggregate, removing on average less than 1% of the aggregate surface

Training Load, Injury Burden, and Team Success in Professional Rugby Union:Risk Versus Reward

CONTEXT: Individual and team injury burden and performance are 2 key considerations facing practitioners in the daily prescription of an athlete's training load. Whereas a considerable number of researchers have examined univariate relationships between training load and performance, training load and injury, or injury and performance, few investigators have examined all 3 concurrently. OBJECTIVE: To assess the association among training load, injury burden, and performance in professional rugby union. DESIGN: Descriptive epidemiology study. SETTING: The English Premiership competition. PATIENTS OR OTHER PARTICIPANTS: Individual injury and training load data, as well as team performance data, were captured during the 2015–2016 (n = 433 players) and 2016–2017 (n = 569 players) seasons. MAIN OUTCOME MEASURE(S): Data were aggregated into team average scores for each week, including weekly (acute) load, smoothed chronic load, changes in load, injury burden, and weekly performance. Linear mixed modelling techniques were used to assess the association among measures. RESULTS: Injury burden was negatively associated with performance, with a high weekly burden associated with a likely harmful (P = .01) decrease in performance. Training load measures displayed only trivial associations with performance. Only the acute:chronic workload ratio measure was clearly associated with injury burden, with a possibly harmful effect (P = .02). Both squad size and player availability were associated with only trivial changes in performance. CONCLUSIONS: Whereas no association between average training load and performance existed, associations between training load and injury burden and between injury burden and performance were clear. Further investigation using more sensitive and individualized measures of load, performance, and injury may elicit a clearer relationship and should be considered for future work

The value of transnational education to the UK

This report provides details on transnational education (TNE) activities by UK higher education institutions (HEIs). Transnational education refers to the provision of education for students based in a country other than the one in which the awarding institution is located. For example, transnational education can be delivered via overseas branch campuses, distance learning or partnerships with overseas institutions. Data is sourced from a survey of HEIs and case studies of TNE programmes. The report provides details on: - the modes of TNE delivery offered by UK HEIs - the number of students studying on TNE programmes offered by UK HEIs - the value of transnational education activities to UK HEI

Reconstructing the accumulation history of a saltmarsh sediment core: which age-depth model is best?

Saltmarsh-based reconstructions of relative sea-level (RSL) change play a central role in current efforts seeking to quantify the relationship between climate and sea-level rise. The development of an accurate chronology is pivotal, since errors in age-depth relationships will propagate to the final record as alterations in both the timing and magnitude of reconstructed change. A range of age-depth modelling packages are available but differences in their theoretical basis and practical operation mean contrasting accumulation histories can be produced from the same dataset. We compare the performance of five age-depth modelling programs (Bacon, Bchron, Bpeat, Clam and OxCal) when applied to the kinds of data used in high resolution, saltmarsh-based RSL reconstructions. We investigate their relative performance by comparing modelled accumulation curves against known age-depth relationships generated from simulated stratigraphic sequences. Bpeat is particularly sensitive to non-linearities which, whilst maximising the detection of small rate changes, has the potential to generate spurious variations, particularly in the last 400 years. Bacon generally replicates the pattern and magnitude of change but with notable offsets in timing. Bchron and OxCal successfully constrain the known accumulation history within their error envelopes although the best-fit solutions tend to underestimate the magnitude of change. The best-fit solutions of Clam generally replicate the timing and magnitude of changes well, but are sensitive to the underlying shape of the calibration curve, performing poorly where plateaus in atmospheric 14C concentration exist. We employ an ensemble of age-depth models to reconstruct a 1500 year accumulation history for a saltmarsh core recovered from Connecticut, USA based on a composite chronology comprising 26 AMS radiocarbon dates, 210Pb, 137Cs radionuclides and an historical pollen chronohorizon. The resulting record reveals non-linear accumulation during the late Holocene with a marked increase in rate around AD1800. With the exception of the interval between AD1500 and AD1800, all modelsproduce accumulation curves that agree to within ~10 cm at the century-scale. The accumulation rate increase around AD1800 is associated with the transition from a radiocarbon-based to a 210Pb dominated chronology. Whilst repeat analysis excluding the 210Pb data alters the precise timing and magnitude of this acceleration, a shift to faster accumulation compared to the long-term rate is a robust feature of the record and not simply an artefact of the switch in dating methods. Simulation indicates that a rise of similar magnitude to the post-AD1800 increase (detrended increase of ~16 cm) is theoretically constrained and detectable within the radiocarbon-dated portion of the record. The absence of such a signal suggests that the recent rate of accumulation is unprecedented in the last 1500 years. Our results indicate that reliable (sub)century-scale age-depth models can be developed from saltmarsh sequences, and that the vertical uncertainties associated with them translate to RSL reconstruction errors that are typically smaller than those associated with the most precise microfossil-based estimates of palaeomarsh-surface elevation