The role of sleep deprivation and fatigue in the perception of task difficulty and use of heuristics

Objectives: This study investigated the effects of sleep deprivation on perception of task difficulty and use of heuristics (mental shortcuts) compared to naturally-experienced sleep at home. Methods: Undergraduate students were screened and assigned through block-random assignment to Naturally-Experienced Sleep (NES; n=19) or Total Sleep Deprivation (TSD; n=20). The next morning, reported fatigue, perception of task difficulty, and use of “what-is-beautiful-is-good,” “greedy algorithm,” and “speed-accuracy trade-off ” heuristics were assessed. Results: NES slept for an average of 354.74 minutes (SD=72.84), or 5.91 hours. TSD rated a reading task as significantly more difficult and requiring more time than NES. TSD was significantly more likely to use the greedy algorithm heuristic by skipping instructions and the what-is-beautiful-is-good heuristic by rating an unattractive consumer item with a favorable review as poor quality. Those in Total Sleep Deprivation who chose more difficult math problems made this selection to finish the task more quickly in findings approaching significance, indicating use of the speed-accuracy trade-off heuristic. Collapsed across conditions, self-reported fatigue predicted greater perceived difficulty in both the reading task and a visuo-motor task, higher quality rating for the attractive consumer item, and lower quality rating for the unattractive consumer item. Conclusions: Findings indicate sleep deprivation and fatigue increase perceptions of task difficulty, promote skipping instructions, and impair systematic evaluation of unappealing stimuli compared to naturally-experienced sleep

Effect of rhenium irradiations on the mechanical properties of tungsten for nuclear fusion applications

As-received and annealed tungsten samples were irradiated at a temperature of 400 °C with Re and W ions to peak concentrations of 1600 appm (atomic parts per million) and damage levels of 40 dpa (displacements per atom). Mechanical properties were investigated using nanoindentation, and the orientation and depth dependence of irradiation damage was investigated using Electron Back Scatter Diffraction (EBSD). Following irradiation there was a 13% increase in hardness in the as received sheet and a 23% increase in the annealed material for both tungsten and rhenium irradiation. The difference between the tungsten and rhenium irradiated samples was negligible, suggesting that for the concentrations and damage levels employed, the presence of rhenium does not have a significant effect on the hardening mechanism. Energy dependent EBSD of annealed samples provided information about the depth distribution of the radiation damage in individual tungsten grains and confirmed that the radiation damage is orientation dependant

Health professionals, their medical interventions and uncertainty : a study focusing on women at midlife

Health professionals face a tension between focusing on the individual and attending to health issues for the population as a whole. This tension is intrinsic to medicine and gives rise to medical uncertainty, which here is explored through accounts of three medical interventions focused on women at midlife: breast screening, hormone replacement therapy and bone densitometry. The accounts come from interviews with UK health professionals using these medical interventions in their daily work. Drawing on the analysis of Fox [(2002). Health and Healing: The public/private divide (pp. 236–253). London: Routledge] we distinguish three aspects of medical uncertainty and explore each one of them in relation to one of the interventions. First is uncertainty about the balance between the individual and distributive ethic of medicine, explored in relation to breast screening. Second is the dilemma faced by health professionals when using medicial evidence generated through studies of populations and applying this to individuals. We explore this dilemma for hormone replacement therapy. Thirdly there is uncertainty because of the lack of a conceptual framework for understanding how new micro knowledge, such as human genetic information, can be combined with knowledge of other biological and social dimensions of health. The accounts from the bone denistometry clinic indicate the beginnings of an understanding of the need for such a framework, which would acknowledge complexity, recognising that factors from many different levels of analysis, from heredity through to social factors, interact with each other and influence the individual and their health. However, our analysis suggests biomedicine continues to be dominated by an individualised, context free, concept of health and health risk with individuals alone responsible for their own health and for the health of the population. This may continue to dominate how we perceive responsibilities for health until we establish a conceptual framework that recognises the complex interaction of many factors at macro and micro level affecting health

Performance measures of the specialty referral process: a systematic review of the literature

<p>Abstract</p> <p>Background</p> <p>Performance of specialty referrals is coming under scrutiny, but a lack of identifiable measures impedes measurement efforts. The objective of this study was to systematically review the literature to identify published measures that assess specialty referrals.</p> <p>Methods</p> <p>We performed a systematic review of the literature for measures of specialty referral. Searches were made of MEDLINE and HealthSTAR databases, references of eligible papers, and citations provided by content experts. Measures were eligible if they were published from January 1973 to June 2009, reported on validity and/or reliability of the measure, and were applicable to Organization for Economic Cooperation and Development healthcare systems. We classified measures according to a conceptual framework, which underwent content validation with an expert panel.</p> <p>Results</p> <p>We identified 2,964 potentially eligible papers. After abstract and full-text review, we selected 214 papers containing 244 measures. Most measures were applied in adults (57%), assessed structural elements of the referral process (60%), and collected data via survey (62%). Measures were classified into non-mutually exclusive domains: need for specialty care (N = 14), referral initiation (N = 73), entry into specialty care (N = 53), coordination (N = 60), referral type (N = 3), clinical tasks (N = 19), resource use (N = 13), quality (N = 57), and outcomes (N = 9).</p> <p>Conclusions</p> <p>Published measures are available to assess the specialty referral process, although some domains are limited. Because many of these measures have been not been extensively validated in general populations, assess limited aspects of the referral process, and require new data collection, their applicability and preference in assessment of the specialty referral process is needed.</p

Prescribed burning, atmospheric pollution and grazing effects on peatland vegetation composition

1. Peatlands are valued for ecosystem services including carbon storage, water provision and biodiversity. However, there are concerns about the impacts of land management and pollution on peatland vegetation and function. 2. We investigated how prescribed vegetation burning, atmospheric pollution and grazing are related to vegetation communities and cover of four key taxa (Sphagnum spp., Calluna vulgaris, Eriophorum vaginatum and Campylopus introflexus) using two datasets from a total of 2,013 plots across 95 peatland sites in the UK. 3. Non‐metric multidimensional scaling and permutational multivariate analysis of variance showed differences in vegetation community composition between burned and unburned plots at regional and national scales. 4. Analysis showed that burned sites had less Sphagnum and greater C. vulgaris cover on a national scale. On a regional scale, plots burned between 2 and 10 years ago had greater cover of invasive moss C. introflexus and less E. vaginatum than unburned sites. 5. Livestock presence was associated with less Sphagnum and C. vulgaris, while atmospheric pollution was associated with less Sphagnum, but greater C. introflexus cover, and appeared to have more impact on burned sites. 6. Synthesis and applications. Burning, grazing and atmospheric pollution are associated with peatland vegetation composition and cover of key species, including Sphagnum. We suggest that, to promote cover of peat‐forming species, peatlands should not be routinely burned or heavily grazed. Current or historical atmospheric pollution may hinder peat‐forming species, particularly on burned sites

The meaning of nursing-home: `Waiting to go up to St. Peter, OK! Waiting house, sad but true´ — An Australian perspective

Background: This article is derived from a larger Australian research study using multiple qualitative methods to investigate truth-telling in aged-care