825 research outputs found
Cartels and search
This paper unifies two significant but somewhat contradictory ideas. First, search costs potentially influence market price equilibria significantly; in many equilibria consumers do not search despite above-competitive prices. Second, cartels must guard against individual members offering lower prices, thereby creating incentives for consumers to search. We develop a simple framework, and then an example, in which whether search takes place depends upon the magnitude of search costs. Three potential equilibria result, dependent upon model parameters. These include a tacit cartel agreement exhibiting price variance and volatility. A policy conclusion is that such market characteristics do not always guarantee non-cartelisation
Effects of three different biochars on aggregate stability, organic carbon mobility and micronutrient bioavailability
Previous studies have demonstrated both beneficial and detrimental effects on soil properties from biochar incorporation. Several biochars, with different feedstock origins, were evaluated for their effectiveness at improving soil quality of a sandy agricultural soil. A pot trial was used to investigate aggregate stability and microbial activity, pore water trace element mobility and micronutrient concentrations in grain of spring wheat after incorporation of three biochars. The feedstocks for biochar production were selected because they were established UK waste products, namely oversize woody material from green waste composting facilities, and rhododendron and soft wood material from forest clearance operations. Biochars were incorporated into the soil at a rate of 5% v/v. Aggregate stability was improved following addition of oversize biochar whilst microbial activity increased in all treatments. Dissolved organic carbon (DOC) concentrations in soil pore water from biochar-treated soils were raised, whilst micronutrient concentrations in wheat grain grown in the treated soils were significantly reduced. It was concluded that incorporation of biochar to temperate agricultural soils requires caution as it may result in reductions of essential grain micronutrients required for human health, whilst the effect on aggregate stability may be linked to organic carbon functional groups on biochar surfaces and labile carbon released from the char into the soil system
Psychometric properties of the Hospital Survey on Patient Safety Culture: findings from the UK
Background: Patient safety culture is measured using a range of survey tools.
Many provide limited data on psychometric properties and few report findings
outside of the USA healthcare context. This study reports an assessment of the
psychometric properties and suitability of the American Hospital Survey on
Patient Safety Culture (HSOPC) for use within the UK.
Methods: A questionnaire survey of three hospitals within a large UK Acute NHS
Trust. 1,437 questionnaires were completed (37% response rate). Exploratory
factor analysis, confirmatory factor analysis, and reliability analyses were carried
out to assess the psychometric performance of this survey instrument and
explore potential improvements.
Results: Reliability analysis of the items within each proposed scale showed that
over half failed to achieve satisfactory internal consistency (Cronbachâs Alpha <
0.7). Furthermore, a confirmatory factor analysis carried out on the UK dataset
achieved a poor fit when compared to the original American model. An optimal
measurement model was then constructed via exploratory and confirmatory
factor analysis with split-half sample validation, and consisted of 9 dimensions
compared to the original 12 in the American model.
Conclusion: This is one of the few studies to provide an evaluation of an
American patient safety culture survey using data from the UK. The results
indicate that there is need for caution in using the HSOPC survey in the UK and
underline the importance of appropriate validation of safety culture surveys
before extending their usage to populations outside of the specific geographical
and health care contexts in which they were developed
Effects of northbound long-haul international air travel on sleep quantity and subjective jet lag and wellness in professional Australian soccer players
© 2015 Human Kinetics, Inc. The current study examined the effects of 10-h northbound air travel across 1 time zone on sleep quantity, together with subjective jet lag and wellness ratings, in 16 male professional Australian football (soccer) players. Player wellness was measured throughout the week before (home training week) and the week of (away travel week) travel from Australia to Japan for a preseason tour. Sleep quantity and subjective jet lag were measured 2 d before (Pre 1 and 2), the day of, and for 5 d after travel (Post 1-5). Sleep duration was significantly reduced during the night before travel (Pre 1; 4.9 [4.2-5.6] h) and night of competition (Post 2; 4.2 [3.7-4.7] h) compared with every other night (P 0.90). Moreover, compared with the day before travel, subjective jet lag was significantly greater for the 5 d after travel (P 0.90), and player wellness was significantly lower 1 d postmatch (Post 3) than at all other time points (P 0.90). Results from the current study suggest that sleep disruption, as a result of an early travel departure time (8 PM) and evening match (7:30 PM), and fatigue induced by competition had a greater effect on wellness ratings than long-haul air travel with a minimal time-zone change. Furthermore, subjective jet lag may have been misinterpreted as fatigue from sleep disruption and competition, especially by the less experienced players. Therefore, northbound air travel across 1 time zone from Australia to Asia appears to have negligible effects on player preparedness for subsequent training and competition
Quantifying the stability of planktic foraminiferal physical niches between the Holocene and Last Glacial Maximum
Both Nucleophile and Substrate Bind to the Catalytic Fe(II)-Center in the Type-II Methionyl Aminopeptidase from \u3cem\u3ePyrococcus furiosus\u3c/em\u3e
Metalloproteases utilize their active site divalent metal ions to generate a nucleophilic water/hydroxide. For methionine aminopeptidases (MetAPs), the exact location of this nucleophile, as well as of the substrate, with respect to the active site metal ion is unknown. In order to address this issue, we have examined the catalytically competent Fe(II)-loaded form of PfMetAP-II ([Fe(PfMetAP-II)]) in the absence and presence of both nitric oxide (NO) and the substrate-analogue inhibitor butaneboronic acid (BuBA) by kinetic and spectroscopic (EPR, UVâvis) methods. NO binds to [Fe(PfMetAPâII)] with a Kd of 200 ÎŒM forming an {FeNO}7 complex. UVâvis spectra of the resulting [Fe(PfMetAPâII)]âNO complex indicate that the Fe(II) ion is six coordinate. These data suggest that NO binding occurs without displacing the bound aquo/hydroxo moiety in [Fe(PfMetAPâII)]. On the basis of EPR spectra, the resulting FeâNO complex is best described as NO- (S = 1) antiferromagnetically coupled to a high-spin Fe(III) ion (S = 5/2). The addition of BuBA to [Fe(PfMetAP-II)]âNO displaces the coordinated water molecule forming a six-coordinate adduct. EPR data also indicate that an interaction between the bound NO- and BuBA occurs forming a complex that mimics an intermediate step between the Michaelis complex and the tetrahedral transition-state
A comparison of three systemic accident analysis methods using 46 SPAD (Signals Passed at Danger) incidents
During the period 1996-2003 there were five fatal accidents on the UK railway network, three of which were Signals Passed at Danger (SPAD) events (Watford Junction, 1996; Southall, 1997; Ladbroke Grove, 1999). SPAD events vary in severity and whilst most are not fatal there is the potential to cause serious injuries to passengers and train staff and damage to railway infra-structure. This paper investigates how the current system accident analysis tool used within the railway, the Incident Factor Classification System (IFCS) identifies and analyses causal factors of SPAD events. To evaluate the effectiveness IFCS was used to analysis SPAD incident reports (n=46) and the outputs were compared with two systemic accident analysis methods and relevant outputs (the Human Factors Analysis and Classification System â HFACS and Acci-Maps). The initial reporting process proved to hinder all systemic accident analysis methods in the extraction of causal factors. However, once extracted, all system accident analysis methods were successful in categorizing causal factors and demonstrated various outputs to illustrate the findings
Patient safety culture among European cancer nurses - an exploratory, cross-sectional survey comparing data from Estonia, Germany, Netherlands and United Kingdom
Aim To explore the differences in perceived patient safety culture in cancer nurses working in Estonia, Germany, the Netherlands and the United Kingdom. Design An exploratory crossâsectional survey. Methods In 2018, 393 cancer nurses completed the 12 dimensions of the Hospital Survey on Patient Safety Culture. Results The mean score for the overall patient safety grade was 61.3. The highest rated dimension was âteamwork within units' while âstaffing' was the lowest in all four countries. Nurses in the Netherlands and in the United Kingdom, scored higher on âcommunication openness', the âfrequency of events reported' and ânonpunitive response to errors', than nurses from Estonia or Germany. We found statistically significant differences between the countries for the association between five of the 12 dimensions with the overall patient safety grade: overall perception of patient safety, communication openness, staffing, handoffs and transitions and nonpunitive response to errors. Conclusion Patient safety culture, as reported by cancer nurses, varies between European countries and contextual factors, such as recognition of the nursing role and education have an impact on it. Cancer nurses' role in promoting patient safety is a key concern and requires better recognition on a European and global level
Defining the methodological challenges and opportunities for an effective science of sociotechnical systems and safety
An important part of the application of sociotechnical systems theory (STS) is the development of methods, tools and techniques to assess human factors and ergonomics workplace requirements. We focus in this paper on describing and evaluating current STS methods for workplace safety, as well as outlining a set of six case studies covering the application of these methods to a range of safety contexts. We also describe an evaluation of the methods in terms of ratings of their ability to address a set of theoretical and practical questions (e.g. the degree to which methods capture static/dynamic aspects of tasks and interactions between system levels). The outcomes from the evaluation highlight a set of gaps relating to the coverage and applicability of current methods for STS and safety (e.g. coverage of external influences on system functioning; method usability). The final sections of the paper describe a set of future challenges, as well as some practical suggestions for tackling these.
Practitioner Summary: We provide an up-to-date review of STS methods, a set of case studies illustrating their use and an
evaluation of their strengths and weaknesses. The paper concludes with a âroadmapâ for future work
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