19,666 research outputs found
Conservation evo-devo: preserving biodiversity by understanding its origins
Unprecedented rates of species extinction increase the urgency for effective conservation biology management practices. Thus, any improvements in practice are vital and we suggest that conservation can be enhanced through recent advances in evolutionary biology, specifically advances put forward by evolutionary developmental biology (i.e., evo-devo). There are strong overlapping conceptual links between conservation and evo-devo whereby both fields focus on evolutionary potential. In particular, benefits to conservation can be derived from some of the main areas of evo-devo research, namely phenotypic plasticity, modularity and integration, and mechanistic investigations of the precise developmental and genetic processes that determine phenotypes. Using examples we outline how evo-devo can expand into conservation biology, an opportunity which holds great promise for advancing both fields
On Vertically Global, Horizontally Local Models for Astrophysical Disks
Disks with a barotropic equilibrium structure, for which the pressure is only
a function of the density, rotate on cylinders in the presence of a
gravitational potential, so that the angular frequency of such a disk is
independent of height. Such disks with barotropic equilibria can be
approximately modeled using the shearing box framework, representing a small
disk volume with height-independent angular frequency. If the disk is in
baroclinic equilibrium, the angular frequency does generally depend on height,
and it is thus necessary to go beyond the standard shearing box approach. In
this paper, we show that given a global disk model, it is possible to develop
approximate models that are local in horizontal planes without an expansion in
height with shearing-periodic boundary conditions. We refer to the resulting
framework as the vertically global shearing box (VGSB). These models can be
non-axisymmetric for globally barotropic equilibria but should be axisymmetric
for globally baroclinic equilibria. We provide explicit equations for this VGSB
which can be implemented in standard magnetohydrodynamic codes by generalizing
the shearing-periodic boundary conditions to allow for a height-dependent
angular frequency and shear rate. We also discuss the limitations that result
from the radial approximations that are needed in order to impose
height-dependent shearing periodic boundary conditions. We illustrate the
potential of this framework by studying a vertical shear instability and
examining the modes associated with the magnetorotational instability.Comment: 24 pages, 8 figures, updated to match published versio
Maximising learning opportunities in handover
Handing over responsibility for patients has always been part of medical practice. Definitions emphasise transfer of responsibility to ensure patient safety and the available literature tends to follow this line (see box 1). Handover is much more than this, however. It is a key event where teams meet, have the opportunity to communicate, support each other and learn. This paper considers different ways of maximising learning opportunities in handover, with particular emphasis on the strengths and challenges of the paediatric environment. Alongside review of the best available evidence, many of the ideas discussed were generated from working with a group of 65 experienced paediatricians with particular experience and interest in medical education as part of the Royal College of Paediatrics and Child Health Paediatric Educators Programme.
Formal handover has increased in importance and been embedded in practice with the transition from âon-callsâ to âfull-shiftâ rotas in an effort to comply with the European Working Time Directive1 in the United Kingdom (UK). Departments responsible for acute patient care have had to incorporate two or three handover sessions into every day to ensure patient problems and management plans are appreciated by the incoming medical team
Recommended from our members
The location of executive suites and business centers in the United States: an exploratory analysis
Increasingly, corporate occupiers seek more flexible ways of meeting their accommodation needs. One consequence of this process has been the growth of the executive suite, serviced office or business centre market. This paper, the final report of a research project funded by the Real Estate Research Institute, focuses upon the geographical distribution of business centers offering executive suites within the US. After a brief review of the development of the market, the paper examines the availability of data, provides basic descriptive statistics of the distribution of executive suites by state and by metropolitan statistical area and then attempts to model the distribution using demographic and socio-economic data at MSA level. The distribution reflects employment in key growth sectors and the position of the MSA in the urban hierarchy. An appendix presents a preliminary view of the global distribution of suites
Ecosystem size predicts eco-morphological variability in a postglacial diversification
Identifying the processes by which new phenotypes and species emerge has been a long-standing effort in evolutionary biology. Young adaptive radiations provide a model to study patterns of morphological and ecological diversification in environmental context. Here, we use the recent radiation (ca. 12k years old) of the freshwater fish Arctic charr (Salvelinus alpinus) to identify abiotic and biotic environmental factors associated with adaptive morphological variation. Arctic charr are exceptionally diverse, and in postglacial lakes there is strong evidence of repeated parallel evolution of similar morphologies associated with foraging. We measured head depth (a trait reflecting general eco-morphology and foraging ecology) of 1,091 individuals across 30 lake populations to test whether fish morphological variation was associated with lake bathymetry and/or ecological parameters. Across populations, we found a significant relationship between the variation in head depth of the charr and abiotic environmental characteristics: positively with ecosystem size (i.e., lake volume, surface area, depth) and negatively with the amount of littoral zone. In addition, extremely robust-headed phenotypes tended to be associated with larger and deeper lakes. We identified no influence of co-existing biotic community on Arctic charr trophic morphology. This study evidences the role of the extrinsic environment as a facilitator of rapid eco-morphological diversification
Primary aragonite and high-Mg calcite in the late Cambrian (Furongian) : Potential evidence from marine carbonates in Oman
Acknowledgements Fieldwork and sampling was funded by Petroleum Development Oman during S. Al Marjibis's Ph.D. Their help is gratefully acknowledged. We also thank colleagues at the University of Aberdeen, Julie Dougans (SUERC) for assisting with stable isotope analysis and Dr. Richard Hinton (EIMF) for assistance with ion microprobe analysis. Profs. Kiessling, Tucker, Bosence, Coleman, Dr. Dickson and an anonymous reviewer are thanked for their helpful and encouraging comments.Peer reviewedPostprin
- âŠ