1,603 research outputs found

    Highlighting when animals expend excessive energy for travel using dynamic body acceleration

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    Travel represents a major cost for many animals so there should be selection pressure for it to be efficient – at minimum cost. However, animals sometimes exceed minimum travel costs for reasons that must be correspondingly important. We use Dynamic Body Acceleration (DBA), an acceleration-based metric, as a proxy for movement-based power, in tandem with vertical velocity (rate of change in depth) in a shark (Rhincodon typus) to derive the minimum estimated power required to swim at defined vertical velocities. We show how subtraction of measured DBA from the estimated minimum power for any given vertical velocity provides a “proxy for power above minimum” metric (PPAmin), highlighting when these animals travel above minimum power. We suggest that the adoption of this metric across species has value in identifying where and when animals are subject to compelling conditions that lead them to deviate from ostensibly judicious energy expenditure

    Organic contaminant content and physico-chemical characteristics of waste materials recycled in agriculture

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    A range of wastes representative of materials currently applied, or with future potential to be applied, to agricultural land in the UK as fertilisers and soil improvers or used as animal bedding in livestock production, were investigated. In addition to full physico-chemical characterization, the materials were analysed for a suite of priority organic contaminants. In general, contaminants were present at relatively low concentrations. For example, polychlorinated dibenzo-p-dioxins/dibenzofurans and polychlorinated biphenyls in biosolids and compost-like-outputs (CLOs) were, in most cases, between 5-50 times lower than proposed and implemented European limit values for biosolids or composts applied to agricultural land. However, the technical basis for these limits may need to be re-evaluated. Polybrominated, and mixed halogenated, dibenzo-p-dioxins/dibenzofurans are not currently considered in risk assessments of dioxins and dioxin-like chemicals, but were detected in the biosolids and compost-like-outputs and their potential contribution to the overall toxic equivalency will be assessed. Other, ‘emerging’ contaminants such as perfluoralkyl compounds (PFCs) and organophosphate flame retardants were detected in several of the waste materials, and their potential significance is discussed. The study is part of a wider research programme that will provide evidence to improve confidence in the use of waste-derived materials in agriculture and establish guidelines to protect the food chain where necessary

    Orientation in high-flying migrant insects in relation to flows: mechanisms and strategies

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    High-flying insect migrants have been shown to display sophisticated flight orientations that can, for example, maximize distance travelled by exploiting tailwinds, and reduce drift from seasonally optimal directions. Here, we provide a comprehensive overview of the theoretical and empirical evidence for the mechanisms underlying the selection and maintenance of the observed flight headings, and the detection of wind direction and speed, for insects flying hundreds of metres above the ground. Different mechanisms may be used—visual perception of the apparent ground movement or mechanosensory cues maintained by intrinsic features of the wind—depending on circumstances (e.g. day or night migrations). In addition to putative turbulence-induced velocity, acceleration and temperature cues, we present a new mathematical analysis which shows that 'jerks' (the time-derivative of accelerations) can provide indicators of wind direction at altitude. The adaptive benefits of the different orientation strategies are briefly discussed, and we place these new findings for insects within a wider context by comparisons with the latest research on other flying and swimming organisms

    The politics of the teaching of reading

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    Historically, political debates have broken out over how to teach reading in primary schools and infant classrooms. These debates and “reading wars” have often resulted from public concerns and media reportage of a fall in reading standards. They also reflect the importance placed on learning to read by parents, teachers, employers, and politicians. Public and media-driven controversies over the teaching of reading have resulted in intense public and professional debates over which specific methods and materials to use with beginning readers and with children who have reading difficulties. Recently, such debates have led to a renewed emphasis on reading proficiency and “standardized” approaches to teaching reading and engaging with literacy. The universal acceptance of the importance of learning to read has also led to vested interests in specific methods, reading programmes, and early literacy assessments amongst professional, business, commercial, and parental lobbying groups. This article traces these debates and the resulting growing support for a quantitative reductionist approach to early-reading programmes

    Baker Center Journal of Applied Public Policy, Vol. I No. I

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    Welcome to the first issue of the Baker Center Journal of Applied Public Policy. Throughout my many years of service, I always have been impressed with the tremendous good that can be accomplished through the creation and implementation of sound public policy. I hope that, along the way, I have contributed to the body of policies that help our nation function in a strong, effective, compassionate, and prosperous fashion. As we launch this new Journal, under the auspices of the Howard H. Baker Jr. Center for Public Policy at the University of Tennnnessee, I wanted to briefly expand on some of the reasons I believe that this journal is necessary and why I believe that research on public policy is so vitally important. This Journal aims to discuss applied public policy. The goal is not to engage in theoretical discussions, though I believe those are important. Instead, we hope that the Baker Journal will focus on the most current issues that directly affect our nation and our world on the operational, or mechanical level. We intend to engage a wide variety of contributors. Scholars, of course, will be asked to write on critical topics of research. We also aim to include contributions from those who draft, approve and execute public policy at the local, state, and national levels. Additionally, at least one article in each issue will be reserved for the work of a university-level student. Our approach is varied, and I know that the result will be an intellectually sound and extraordinarily interesting presentation of experiences and ideas.I am especially pleased that so many University of Tennnnessee students are involved in the formulation and operation of the Journal. Our editorial board is comprised of some of the University of Tennnnessee’s most promising undergraduate, graduate, and law school students. With dedicated assistance and oversight from faculty and from the Baker Center, this board of extraordinarily intelligent and committed students has worked very hard to make this Journal a reality. The Center has also formed a national advisory panel for the Journal. I am a member of that panel, and I must note that I am grateful for the involvement and support of my colleagues who have agreed to serve with me: Ms. Emily Reynolds, former Secretary of the United States Senate; Congressman Bob Clement, former Tennnnessee Congressman; Mr. Glennnn Reynolds, noted author and professor of law at the University of Tennnnessee; Dr. Joseph Cooper, an accomplished professor of political science at Johns Hopkins University; and Mr. John Seigenthaler, distinguished journalist and founder and director of the First Amendment Center at Vanderbilt University. I believe it is critical that we think deeply about the issues that are confronting us today. Our representative system of governance is based on an informed citizenry and informed public servants. From international issues such as the war on terror and energy challenges to more local but equally important topics such as sustainable development and education, we must commit ourselves to understanding all challenges free of partisan rhetoric. Only then can we confront them together. It is my hope that this Journal will add to that understanding and will speak to many audiences. From the classroom to the boardroom, from city hall to the halls of our legislatures, I believe the work put forward in our journal will be useful for everyone who wants to be informed and engaged. It is an exciting undertaking, and I thank you for your support
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