WISDOM: history and early demise - was it inevitable?

In 1989, the UK Medical Research Council (MRC) agreed that, if feasible, a randomized controlled trial to assess the long-term risks and benefits of hormone replacement therapy (HRT) was a priority. Feasibility work began in 1990 and demonstrated that a large-scale multicenter trial was possible. An application for funding for a main trial was submitted to MRC in 1993 and, after extensive review, funding was released in late 1996. Set-up work for the trial - the Women's International Study of long Duration Oestrogen after Menopause (WISDOM) - began in 1997 with recruitment in 1999. In October 2002, following the early discontinuation of one arm of the US Women's Health Initiative HRT trial, the MRC decided to stop the WISDOM trial. This article, by the principal UK investigators of WISDOM, sets out the background and history of the trial

The first UK records of the purple fan-worm, Bispira polyomma Giangrande & Faasse, 2012 (Annelida: Sabellidae

The sabellid polychaete Bispira polyomma Giangrande & Faasse, 2012 was found during summer–autumn 2021 in substantial numbers in two adjacent marinas in Plymouth, SW England. These are apparently the first UK reports, coming over a decade after the species’ discovery and description, as a presumed non-native, in the SW Netherlands. Further morphological details of the species and notes on variation between individuals are provided. It seems probable that records of Bispira fabricii in Le Havre commencing in 2010, and at other sites on the French north coast, also relate to B. polyomma. An apparent association with marinas and ports suggests roles for recreational boats and commercial shipping in the dispersal of this species

Travelling waves in pipe flow

A family of three-dimensional travelling waves for flow through a pipe of circular cross section is identified. The travelling waves are dominated by pairs of downstream vortices and streaks. They originate in saddle-node bifurcations at Reynolds numbers as low as 1250. All states are immediately unstable. Their dynamical significance is that they provide a skeleton for the formation of a chaotic saddle that can explain the intermittent transition to turbulence and the sensitive dependence on initial conditions in this shear flow.Comment: 4 pages, 5 figure

Deaf children's understanding of emotions: desires take precedence

Deaf children frequently have trouble understanding other people's emotions. It has been suggested that an impaired theory of mind can account for this. This research focused on the spontaneous use of mental states in explaining other people's emotions by 6- and 10-year-old deaf children as compared to their hearing peers. Within both age-groups deaf children referred to others' beliefs as often as their hearing peers and their references to desires even exceeded those of hearing children. This relative priority for the expression of desires is discussed in terms of possible communicative patterns of deaf children. The specific problems that deaf children meet in their daily communication might explain their abundance of desire-references: plausibly, they give a high priority to stress their own desires and needs unambiguously

How does flow in a pipe become turbulent?

The transition to turbulence in pipe flow does not follow the scenario familiar from Rayleigh-Benard or Taylor-Couette flow since the laminar profile is stable against infinitesimal perturbations for all Reynolds numbers. Moreover, even when the flow speed is high enough and the perturbation sufficiently strong such that turbulent flow is established, it can return to the laminar state without any indication of the imminent decay. In this parameter range, the lifetimes of perturbations show a sensitive dependence on initial conditions and an exponential distribution. The turbulence seems to be supported by three-dimensional travelling waves which appear transiently in the flow field. The boundary between laminar and turbulent dynamics is formed by the stable manifold of an invariant chaotic state. We will also discuss the relation between observations in short, periodically continued domains, and the dynamics in fully extended puffs.Comment: for the proceedings of statphys 2

Fractal Stability Border in Plane Couette Flow

We study the dynamics of localised perturbations in plane Couette flow with periodic lateral boundary conditions. For small Reynolds number and small amplitude of the initial state the perturbation decays on a viscous time scale $t \propto Re$. For Reynolds number larger than about 200, chaotic transients appear with life times longer than the viscous one. Depending on the type of the perturbation isolated initial conditions with infinite life time appear for Reynolds numbers larger than about 270--320. In this third regime, the life time as a function of Reynolds number and amplitude is fractal. These results suggest that in the transition region the turbulent dynamics is characterised by a chaotic repeller rather than an attractor.Comment: 4 pages, Latex, 4 eps-figures, submitted to Phys. Rev. Le

Nursing heroism in the 21st Century'

Abstract Background The Vivian Bullwinkel Oration honours the life and work of an extraordinary nurse. Given her story and that of her World War II colleagues, the topic of nursing heroism in the 21st century could not be more germane. Discussion Is heroism a legitimate part of nursing, or are nurses simply 'just doing their job' even when facing extreme personal danger? In this paper I explore the place and relevance of heroism in contemporary nursing. I propose that nursing heroism deserves a broader appreciation and that within the term lie many hidden, 'unsung' or 'unrecorded' heroisms. I also challenge the critiques of heroism that would condemn it as part of a 'militarisation' of nursing. Finally, I argue that nursing needs to be more open in celebrating our heroes and the transformative power of nursing achievements. Summary The language of heroism may sound quaint by 21st Century standards but nursing heroism is alive and well in the best of our contemporary nursing ethos and practice.</p

Postwildfire Soil Trajectory Linked to Prefire Ecosystem Structure in Douglas-Fir Forest

Changes in soil C and N pools following wildfire are quite varied, but there is little understanding of the causes of the variation. We examined how the legacies of prefire ecosystem structure may explain the variation in soil trajectories during the first decade following wildfire. Five years prior to wildfire in a southwestern Oregon forest dominated by mature Douglas-fir [Pseudotsuga menziesii var. menziesii (Mirb.) Franco], ecosystem structure was experimentally manipulated by thinning or clearcutting for comparison with unthinned forest. Repeated measurements of replicated experimental units were made before wildfire and during the first decade following wildfire. In the unthinned forest, the O-horizon soil C and N pools were decreased to 24–39% of prefire levels by wildfire, then increased to 53–70% during the first year postwildfire by deposition of fire-killed needles from overstory trees. The mineral soil (0–6 cm depth) C pool was decreased by wildfire, then increased in the following decade, while no change in the N pool was detected. In contrast, in the clearcut treatment, the O-horizon soil C and N pools were nearly totally consumed during the wildfire, lacked fire-killed overstory as a source of needle and fine and coarse wood inputs, but regained 20% of prefire masses in the following decade via foliar and root inputs from regenerated shrubs and herbaceous vegetation. Surface mineral soil C and N pools were decreased 35–50% by wildfire and showed no sign of recovery during the following decade. In contrast to wildfire, unburned ecosystem structures showed no changes in O horizon and increased mineral-soil N pool in the clearcut. We propose a conceptual model of soil C and N response following wildfire that includes legacy influences resulting from prefire ecosystem structures: residual live trees that generate continual litterfall and root turnover; fire-killed trees that produce needle-fall, dead roots, and fine- and coarse-wood detritus; and surviving roots and burls that contribute to postwildfire shrub regeneration. Consideration of prefire ecosystem structure and legacies in quantitative models may improve forecasts of postwildfire C budgets at stand to regional scales.Keywords: legacy, soil nitrogen, fine woody debris, soil carbon, postwildfire change, forest management, wildfir

Forest Structure Affects Soil Mercury Losses in the Presence and Absence of Wildfire

Soil is an important, dynamic component of regional and global mercury (Hg) cycles. This study evaluated how changes in forest soil Hg masses caused by atmospheric deposition and wildfire are affected by forest structure. Pre and postfire soil Hg measurements were made over two decades on replicate experimental units of three prefire forest structures (mature unthinned, mature thinned, clear-cut) in Douglas-fir dominated forest of southwestern Oregon. In the absence of wildfire, O-horizon Hg decreased by 60% during the 14 years after clearcutting, possibly the result of decreased atmospheric deposition due to the smaller-stature vegetative canopy; in contrast, no change was observed in mature unthinned and thinned forest. Wildfire decreased O-horizon Hg by >88% across all forest structures and decreased mineral-soil (0 to 66 mm depth) Hg by 50% in thinned forest and clear-cut. The wildfire-associated soil Hg loss was positively related to the amount of surface fine wood that burned during the fire, the proportion of area that burned at >700 °C, fire severity as indicated by tree mortality, and soil C loss. Loss of soil Hg due to the 200 000 ha wildfire was more than four times the annual atmospheric Hg emissions from human activities in Oregon