361 research outputs found

    Analytical studies on commercial artists’ colour charts from Das Deutsche Farbenbuch (1925)—identification of synthetic and natural organic colourants by Raman microscopy, surface-enhanced Raman spectroscopy and metal underlayer ATR-FTIR spectroscopy

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    Historical colour charts provide a rich and often well-dated reference materials source for studying the chemical composition of all kinds of commercial brands of artists' paints. This article presents the results of an extensive analytical study of more than 80 paint hues from 11 colour charts that are included in the German standard book Das Deutsche Farbenbuch by H. Trillich (1925, Part II). Our research focused on the identification of synthetic organic pigments, whose quickly increasing significance for artists' paints in the early twentieth century is impossible to evaluate by documentary source research alone. A stepwise procedure combining different non- or minimally invasive vibrational spectroscopy techniques-Normal Raman and Surface-Enhanced Raman spectroscopy as well as Metal Underlayer Attenuated Total Reflection Fourier-transform Infrared Spectroscopy-allowed the identification of 18 different organic colourants in artists' watercolours, tempera and oil colours from six German manufacturers. In addition, micro-X-Ray Fluorescence spectroscopy was applied to determine the elemental pattern of substrates, fillers, and admixed inorganic pigments. In addition to a few traditional natural organic colourants (dark and rose madder lake, cochineal lake), most of the identified compounds comprised synthetic organic pigments or synthetic dyes from various chemical classes (indigo, anthraquinone, monoazo, ss-naphthol, xanthene, triarylcarbonium, nitroso, and azine compounds). Some of these have not or only rarely been reported in artists' paints so far. Since the identified organic colourants have mainly poor to fair (only sometimes good) fastness to light according to modern standards and partially also to solvents typically used in conservation treatments, it is evident that works of art from this period should be treated keeping in mind the possible presence of such colourants, when planning both interventive treatments and preventive measures

    Driving Factors of Recommending a Hand Surgery Clinic After Surgery

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    Purpose: Since a patient's recommendation of a clinic to others is an important indicator of patient experience, more insight is needed into the underlying factors that motivate such recommendations. This retrospective cohort study assessed the relative contribution of the following: (1) patient-related characteristics, (2) treatment outcome, (3) satisfaction with treatment outcome, and (4) patients’ experience with the process of care to patients’ recommendation of a specific clinic after elective surgery. Methods: Patients of specialized outpatient hand surgery clinics (N = 6,895) reported the likelihood of recommending the clinic to friends or family 3–5 months after surgery by filling in the Net Promoter Score. Potential predictors of the Net Promoter Score were preoperative patient characteristics, patient-reported treatment outcomes, satisfaction with treatment outcome, and experience with several health care delivery domains. Linear regression analyses were used to examine the contribution of the predictors. Results: Mean age of the patients was 53 (SD, 14) years, 62.5% were women, and 62.5% were employed. Preoperative patient characteristics explained 1% of the variance in clinic recommendations. An additional 6% was explained by the treatment outcome, 21.6% by satisfaction with treatment outcome, and 33.8% by patients’ experience with care delivery (total explained variance was 62.3%). The strongest independent predictors of clinic recommendations were positive experiences with the quality of the facilities and the communication skills of the physician. Conclusions: Patient recommendations are more strongly driven by patients’ experience with care delivery than by treatment outcome and patient characteristics. Clinical relevance: In elective surgery, improving patient experiences is pivotal in boosting patient recommendation of the clinic.</p

    Characterization of commercial synthetic resins by pyrolysis-gas chromatography/mass spectrometry : application to modern art and conservation

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    To characterize a set of synthetic resins, a methodology by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) has been developed. The studied reference materials were commercial versions of a wide range of synthetic resins. For each polymer, the pyrolytic and chromatographic conditions were optimized to adequately resolve the fragment mixture in a short time. The proposed analytical method does not require previous treatment of the sample, and due to its high sensitivity, only a small sample quantity in the microgram range can be used. The pyrolysis temperature was found to have little effect on the obtained pyrograms. The summarized data set for the individual polymer materials, especially the characteristic fragments with a structure close to the monomeric unit, was useful to identify commercial synthetic resins. These materials were used in the art and conservation field, as binding media, paint additives, painting varnishes, coatings, or consolidants. Two case studies are introduced where direct Py-GC/MS and thermally assisted hydrolysis and methylation GC/MS were applied on art objects: first, a modern gluing material of a medieval reverse glass painting, and the second example, the binding medium of a painting by Georg Baselitz (“Senta”, 1992/1993) from the Sammlung Moderne Kunst at the Pinakothek der Moderne, MunichVersió editoria

    Reduced use of antimicrobials after vaccination of pigs against porcine proliferative enteropathy in a Danish SPF herd

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    The present study explored whether the use of group medication with antibiotics in a Danish pig herd was reduced after vaccination of the pigs against proliferative enteropathy (PE) caused by Lawsonia intracellularis. 7900 pigs originating from a single commercial sow herd were vaccinated against L. intracellularis, whereas 7756 pigs were kept as non-vaccinated controls. The pigs were included batch-wise in the study with every second batch being vaccinated. In the vaccinated batches, the consumption of oxytetracykline to treat PE was reduced by 79%, with a significantly lower number of pigs being treated (P < 0.0001). Vaccination also resulted in a highly significant improvement of average daily weight gain (+ 46 g/day; P = 9.55 × 10-31) and carcase weight (+ 1.25 kg; P = 4.54 × 10-05) as well as a shortened fattening period (-8 days; P = 2.01 × 10-45)

    Data warehouse for assessing animal health, welfare, risk management and –communication

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    The objective of this paper is to give an overview of existing databases in Denmark and describe some of the most important of these in relation to establishment of the Danish Veterinary and Food Administrations’ veterinary data warehouse. The purpose of the data warehouse and possible use of the data are described. Finally, sharing of data and validity of data is discussed. There are databases in other countries describing animal husbandry and veterinary antimicrobial consumption, but Denmark will be the first country relating all data concerning animal husbandry, -health and -welfare in Danish production animals to each other in a data warehouse. Moreover, creating access to these data for researchers and authorities will hopefully result in easier and more substantial risk based control, risk management and risk communication by the authorities and access to data for researchers for epidemiological studies in animal health and welfare

    Within-day repeatability for absolute quantification of Lawsonia intracellularis bacteria in feces from growing pigs

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    Absolute quantification of Lawsonia intracellularis by real-time polymerase chain reaction (PCR) is now possible on a routine basis. Poor repeatability of quantification can result in disease status misclassification of individual pigs when a single fecal sample is obtained. The objective of the current study was to investigate overall variation within a day for fecal numbers of L. intracellularis bacteria determined by real-time PCR in growing pigs. From each of 30 pigs with an infection of L. intracellularis, 5 fecal samples were collected within 1 day. A total of 150 fecal samples were obtained and subjected to quantitative PCR (qPCR) testing. Mean fecal dry matter content was 14.3% (standard deviation = 4.5%). Two pigs (6.7%) alternated between being L. intracellularis qPCR positive and negative. For 28 pigs, the excreting levels of L. intracellularis were within the dynamic range of the qPCR assay at all sampling points. For these 28 pigs, the mean excretion level of L. intracellularis was 6.1 log10 bacteria/g feces (standard deviation = 1.2 log10 bacteria/g feces). The maximum observed difference between 2 fecal samples from the same pig was 1.1 log10 bacteria/g feces. The average standard deviation for individual pigs was 0.27 log10 bacteria/g feces. The average coefficient of variation within pigs was 0.04, ranging from 0.006 to 0.08. The results imply that absolute quantification of L. intracellularis by qPCR has acceptable repeatability within 1 day. However, a population-specific proportion of pigs alternating between positive and negative test results must be expected. </jats:p
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