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Selected AbstractsA Raman spectroscopic and combined analytical approach to the restoration of severely damaged frescoes: the Palomino projectJOURNAL OF RAMAN SPECTROSCOPY, Issue 4 2008Howell G. M. Edwards Abstract The deterioration of art objects is normally relatively minor, controllable and attributable to environmental changes or bacterial invasion, and until now there has not been any recorded attempt to analyse an artwork that has been deliberately and significantly destroyed. The analytical problems are correspondingly larger but the potential reward from any information that can be forthcoming is thereby proportionately greater. The 17th Century Palomino frescoes on the vaulted ceiling of the Church of Sant Joan del Mercat in Valencia were largely destroyed by insurgents in the Spanish Civil War in 1936. The ensuing gunfire and a series of seven conflagrations inside the church had a devastating effect upon the artwork, and the surviving areas were also rendered unstable with respect to their detachment from the substrate. During the current restoration project being undertaken on these frescoes, an opportunity was provided for the application of several analytical techniques to secure information about the original pigment palette employed, the technology of application used by Palomino and the changes consequent upon the destruction process. Here, we report for the first time the use of analytical Raman spectroscopy, supported by scanning electron microscopy (SEM) and voltammetry of microparticles, for the combined identification of pigments, binders, substrate treatments and pigment alteration in an important, although badly damaged, wall painting for the informing of the ongoing conservation and restoration strategy. Copyright © 2008 John Wiley & Sons, Ltd. [source] Chemical and morphological features of dental composite resin: Influence of light curing units and immersion mediaMICROSCOPY RESEARCH AND TECHNIQUE, Issue 3 2010Patrícia Aleixo Dos Santos Abstract Aims: The study evaluated the influence of light curing units and immersion media on superficial morphology and chemistry of the nanofilled composite resin Supreme XT (3M) through the EDX analysis and SEM evaluation. Light curing units with different power densities and mode of application used were XL 3000 (480 mW/cm2), Jet Lite 4000 Plus (1230mW/cm2), and Ultralume Led 5 (790 mW/cm2) and immersion media were artificial saliva, Coke®, tea and coffee, totaling 12 experimental groups. Specimens (10 mm × 2 mm) were immersed in each respective solution for 5 min, three times a day, during 60 days and stored in artificial saliva at 37°C ± 1°C between immersion periods. Topography and chemical analysis was qualitative. Findings: Groups immersed in artificial saliva, showed homogeneous degradation of matrix and deposition of calcium at the material surface. Regarding coffee, there was a reasonable chemical degradation with loss of load particles and deposition of ions. For tea, superficial degradation occurred in specific areas with deposition of calcium, carbon, potassium and phosphorus. For Coke®, excessive matrix degradation and loss of load particles with deposition of calcium, sodium, and potassium. Conclusion: Light curing units did not influence the superficial morphology of composite resin tested, but the immersion beverages did. Coke® affected material's surface more than did the other tested drinks. Microsc. Res. Tech., 2010. © 2009 Wiley-Liss, Inc. [source] Commentary: Business,Black Swans,and the,Use and Abuse,of a NotionAUSTRALIAN ACCOUNTING REVIEW, Issue 2 2010Graeme Dean Historical enquiry reveals how ideas mutate. This paper traces how ideas and practices underpinning initial understandings of fair value accounting (FVA) have changed as the concept drifted from the utility rate-setting context to that of corporate financial reporting. The recall of history for the purpose of ,learning lessons from the past' has frequently resulted in misunderstandings of the historical record and misapplication of so-called lessons. A more fruitful approach to recalling history is to gain insights into the development of the ideas (good and bad) that have contributed to current predicaments. Initially fair value was the basis for specific pricing calculations related to companies with a highly restricted scope of operations. Later, more by accident than design, the concept became a general purpose application used in the financial statements of highly and freely adaptive companies. The mark-to-market (MtM) dispute emerging in the global financial crisis (GFC) has given rise to a further mutation of the use of FVA. Discarding MtM contradicts what history tells us was the purpose of adopting fair value into accounting for adaptive companies. This analysis also highlights how conducive accounting theory and practice are subject to politicisation. Accounting is an apparently unresisting victim of interested parties' special pleading, resulting in the corruption of its technical function , in this case primarily because it is inconvenient to have accounting data,tell it how it is. [source] Steady- and unsteady-state lumped parameter modelling of tritium and chlorofluorocarbons transport: hypothetical analyses and application to an alpine karst aquiferHYDROLOGICAL PROCESSES, Issue 17 2005N. Nur Ozyurt Abstract Determination of a groundwater's mean residence time with the aid of environmental tracers is common in hydrogeology. Many of the lumped parameter (LP) applications used for this purpose have been based on steady-state models. However, the results may be misleading if a steady LP model is used to simulate the environmental tracer transport in an unsteady aquifer. To test this hypothesis, the results of steady and unsteady versions of several LP models were evaluated theoretically and in an alpine karst aquifer case by using tritium, oxygen-18 and chlorofluorocarbons (CFCs). The results reveal that the mean residence times obtained may be significantly different between the steady and unsteady versions of the same model. For the karst aquifer investigated, a serially connected exponential and a plug flow model were run under unsteady conditions. It is shown that outflux calibration with an unsteady model provides a firm basis in evaluating the results of models. An outflux-calibrated unsteady model predicted reasonably the observed series of water isotopes. The calibrated model's CFCs output overpredicts the observed concentrations, probably because of the time lag in the unsaturated zone of the alpine karst aquifer. Copyright © 2005 John Wiley & Sons, Ltd. [source] Mass spectrometry in newborn and metabolic screening: historical perspective and future directionsJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 2 2009Donald H. Chace Abstract The growth of mass spectrometry (MS) in clinical chemistry has primarily occurred in two areas: the traditional clinical chemistry areas of toxicology and therapeutic drug monitoring and more recent, human genetics and metabolism, specifically inherited disorders of intermediary metabolism and newborn screening. Capillary gas chromatography and electrospray tandem MS are the two most common applications used to detect metabolic disease in screening, diagnostics and disease monitoring of treated patients. A few drops of blood from several million newborn infants are screened annually throughout the world making this the largest application of MS in medicine. Understanding the technique, how it grew from a few dozen samples per week in the early 1990s to increasing daily volume today will provide important information for new tests that either expand newborn screening or screening in other areas of metabolism and endocrinology. There are numerous challenges to the further expansion of MS in clinical chemistry but also many new opportunities in closely related applications. The model of newborn screening and MS in medicine may be useful in developing other applications that go beyond newborns and inherited metabolic disease. As MS continues to expand in clinical chemistry, it is clear that two features will drive its success. These features are excellent selectivity and multiple analyte or profile analysis; features recognized in the 1950s and remain true today. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||