3,552 research outputs found

    Autoxidation of lipids in parchment

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    Historic parchment is a macromolecular material, which is complex due to its natural origin, inhomogeneity of the skin structure, unknown environmental history and potential localised degradation. Most research into its stability has so far focussed on thermal and structural methods of analyses. Using gas chromatographic analysis of the atmosphere surrounding parchment during oxidation, we provide the experimental evidence on the production of volatile aldehydes, which can be the products of lipid autoxidation. Oxidation of parchment with different aldehyde emissions was additionally followed in situ using chemiluminometry and the same techniques were used to evaluate the oxidation of differently delipidised parchment. It was shown that the production of peroxides and the emission of aldehydes from the material decrease with lower lipid content. Building on this evidence, we can conclude that the presence of lipids (either initially present in the skin or resulting from conservation intervention) leads to oxidative degradation of collagen and that the non-destructive analysis of the emission of volatiles could be used as a quick tool for evaluation of parchment stability

    The spillover effects of monitoring:A field experiment

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    Published Online: March 13, 2015We provide field experimental evidence of the effects of monitoring in a context where productivity is multidimensional and only one dimension is monitored and incentivized. We hire students to do a job for us. The job consists of identifying euro coins. We study the direct effects of monitoring and penalizing mistakes on work quality and evaluate spillovers on unmonitored dimensions of productivity (punctuality and theft). We find that monitoring improves work quality only if incentives are harsh, but substantially reduces punctuality irrespectively of the associated incentives. Monitoring does not affect theft, with 10% of participants stealing overall. Our findings are supportive of a reciprocity mechanism, whereby workers retaliate for being distrusted

    Postoperative and Postpartum Onset of Chronic Parkinsonism: Four Case Reports

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    Background: Certain environmental exposures have been linked to the development of parkinsonism. We report four cases in which the onset of chronic parkinsonism occurred immediately or soon after surgery or childbirth. Results: Exposure to certain anesthetic agents in susceptible individuals or the physiological changes associated with surgery or childbirth may have contributed to or precipitated the development of parkinsonism. Conclusion: Clinicians should be aware that postoperative or postpartum settings are potential precipitants of chronic parkinsonism.  More research is needed to clarify contributing factors

    Submergence of magnetic flux in interaction of sunspot groups

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    Submergence of magnetic flux is demonstrated in the process of evolution of sunspot groups NOAA 6850 (26 Sep.-07 Oct. 1991) and 7220/22 (06-17 July 1992). In both cases new magnetic flux emerges immediately behind an existing spotgroup. The new flux does not interact with the old one, as can be seen in YOHKOH X-ray images, so no significant flare activity occurs, although umbrae of different magnetic polarity collide. In both cases the quickly forward moving p-spots of the new flux force the submergence of the f-spots of the older region, these being squeezed from two sides between the old and new p-spots. This leads to the disappearance of about 16 1021 Mx of f-polarity in AR 6850. In the case of this region the submerged flux interacts with newly emerging magnetic fields and in the next rotation continues its life as the complex and eruptive AR 6891. In AR 7220/22, spots of both polarities submerge in the intermediate part of the complex between the old leader of AR 7220 and the quickly growing AR 7222, leaving in the next rotation a bipolar-looking group (AR 7248), consisting of two p-polarity spots. So, submergence of magnetic flux due to interaction of old and new activity may play an important role in the decay of sunspot groups

    Systematic review of the Exploration, Preparation, Implementation, Sustainment (EPIS) framework

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    Background: Effective implementation of evidence-based practices (EBPs) remains a significant challenge. Numerous existing models and frameworks identify key factors and processes to facilitate implementation. However, there is a need to better understand how individual models and frameworks are applied in research projects, how they can support the implementation process, and how they might advance implementation science. This systematic review examines and describes the research application of a widely used implementation framework, the Exploration, Preparation, Implementation, Sustainment (EPIS) framework. Methods: A systematic literature review was performed to identify and evaluate the use of the EPIS framework in implementation efforts. Citation searches in PubMed, Scopus, PsycINFO, ERIC, Web of Science, Social Sciences Index, and Google Scholar databases were undertaken. Data extraction included the objective, language, country, setting, sector, EBP, study design, methodology, level(s) of data collection, unit(s) of analysis, use of EPIS (i.e., purpose), implementation factors and processes, EPIS stages, implementation strategy, implementation outcomes, and overall depth of EPIS use (rated on a 1-5 scale). Results: In total, 762 full-text articles were screened by four reviewers, resulting in inclusion of 67 articles, representing 49 unique research projects. All included projects were conducted in public sector settings. The majority of projects (73%) investigated the implementation of a specific EBP. The majority of projects (90%) examined inner context factors, 57% examined outer context factors, 37% examined innovation factors, and 31% bridging factors (i.e., factors that cross or link the outer system and inner organizational context). On average, projects measured EPIS factors across two of the EPIS phases (M = 2.02), with the most frequent phase being Implementation (73%). On average, the overall depth of EPIS inclusion was moderate (2.8 out of 5). Conclusion: This systematic review enumerated multiple settings and ways the EPIS framework has been applied in implementation research projects, and summarized promising characteristics and strengths of the framework, illustrated with examples. Recommendations for future use include more precise operationalization of factors, increased depth and breadth of application, development of aligned measures, and broadening of user networks. Additional resources supporting the operationalization of EPIS are available
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