19 research outputs found

    Characterization of the evolution of indigo blue by multispectral imaging

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    FEDER/Junta de Andalucia-Consejeria de Economia y Conocimiento, Grant/Award Number: A-HUM-164-UGR18; Ministry of Economy and Competitiveness of Spain, Grant/Award Number: DPI2015-64571-R; Spanish Ministry of Economy and Competitiveness, Grant/Award Number: Ramon y Cajal program; Ministry of Economy and Competitiveness; Junta de Andalucia; FEDER (European Regional Development Fund).Indigo blue is a natural organic color from the Indigofera tinctoria plant. It is insoluble in water and does not require mordant to fix the color; therefore, due to its nature it can be considered as a pigment or dye. The identification of indigo in cultural heritage is very difficult due to the complexity of its chemical formula and the changes that it can undergo in certain conservation and exposition conditions. For this reason, characterization of possible degradation, transformation, and reaction processes is essential for its identification. In this study, multispectral imaging has been used for the first time as noninvasive technique to characterize the aging state of indigo blue using samples aged in a controlled climate chamber under extreme conditions of humidity, temperature, and light. The technique has proven to be very promising for this application, together with classification techniques based on machine learning approaches.FEDER/Junta de Andalucia-Consejeria de Economia y Conocimiento A-HUM-164-UGR18Ministry of Economy and Competitiveness of Spain DPI2015-64571-RSpanish Ministry of Economy and CompetitivenessMinistry of Economy and CompetitivenessJunta de AndaluciaEuropean Commissio

    Estudio colorimétrico de barnices tradicionales aplicados sobre papel sometidos a ensayos de envejecimiento acelerado

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    El empleo de barnices como acabado final en obra gráfica cumple una función estética y protectora. Con el tiempo, o debido a factores adversos, estos barnices pueden sufrir una serie de alteraciones en su color, distorsionando el aspecto original de la obra subyacente. Conocer las variaciones cromáticas de estos materiales resulta esencial de cara a su selección como barniz de conservación. Este trabajo recoge los resultados obtenidos del estudio colorimétrico llevado a cabo sobre una serie de probetas de papel barnizadas sometidas a distintos ensayos físico-químicos (humedad ambiental, inmersión en agua, calor seco y envejecimiento acelerado en cámara climática) que buscan recrear condiciones adversas a las que pueden verse sometidos este tipo de documentos como consecuencia de su envejecimiento natural, la acción de determinados factores de degradación o la acción restauradora. El papel seleccionado como soporte ha sido Somerset 100% algodón al que se le han aplicado distintos barnices de uso tradicional en obra gráfica: goma laca, goma arábiga, clara de huevo, colofonia y dammar). El color de estas probetas se ha estudiado siguiendo el sistema CIEL*a*b* 1976, calculando las diferencias colorimétricas antes y después de los ensayos físico-químicos y de envejecimiento.The use of varnishes as a final coat in graphic work fulfills an aesthetic and protective function. Over time, or due to adverse conditions, these varnishes undergo a series of degradations in their color that can distort the original appearance of the underlying work. Knowing the chromatic variations of these materials is essential for their selection as a conservation varnish. This work collects the results obtained from the colorimetric study carried out on a series of samples of paper with varnish exposing to different physical-chemical tests (humidity, immersion in water, dry heat and accelerated aging) tests that recreate adverse conditions to which this type of woks may be exposed as a consequence of its natural aging, the action of certain degradation factors or the restorative action. For this purpose, Somerset 100% cotton paper has been selected, which has been applied different varnishes of traditional use in graphic works: shellac, gum arabic, egg white, rosin and dammar. The color of these samples has been studied following the CIEL*a*b* 1976 system, calculating the colorimetric differences from the comparison between the reference samples and the samples after the physical-chemical tests

    Non-Invasive Study of the Pigments of a Painting on Copper with the Inscription “Boceto di Pablo Veronese” on the Back

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    The palette used on a small painting on copper support, with the inscription “Boceto di Pablo Veronese” on the back, was characterized. Non-invasive techniques such as X-ray diffraction (XRD) and hand-held X-ray fluorescence (XRF) were proven to be highly effective for this. The objectives of the proposed work were twofold. On the one hand, the objective was the study, in situ, of the pigments of a painting on a copper support. On the other hand, it was to enrich the literature related to the study of paintings on metal supports, since few related studies are available despite the relatively large number of such 16th and 17th century paintings from Italy and Northern Europe. The results of the analysis showed a copper support with a base layer of gypsum mixed with ochre earths. Atop this layer is a sketch with lead white in the lighter areas and bone black in the darker shadow areas, suggesting that the artist performed a preliminary study of the luminosity of the scene. Finally, the upper or pictorial layer consists of a mix of pigments with some lead white to lower saturation and increase lightness, particularly evident in the flesh tones. The resulting palette thus includes lead white, vermilion, bone black, Naples yellow, and lazurite pigments. These results are compared to Veronese’s other paintings, as well as to those of certain contemporary artists, and the use of the resulting pigments in 16th and 17th century Italian painting techniques is discussedProject FEDER/Junta de Andalucía-Consejería de Economía y Conocimiento/A-HUM-164-UGR18Research group FQM-338Analytical Techniques Unit EQC2018-004952-

    A combination of invasive and non-invasive techniques for the study of the palette and painting structure of a copy of Raphael’s Transfguration of Christ

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    We thank the owner of the painting Mr. F. Fernandez Fábregas and the research group FQM-338 (University of Granada) for letting us use its facilities. We also thank Maria José Campos for the preparation of the cross-section samplesAll the authors belong to the research team Unit of Non-Invasive Analytical Techniques Unit (University of Granada, Spain) funded by EQC2018-004952-P and A‐HUM‐164‐UGR18 Projects, currently active. All the authors read and approved the fnal manuscript. EM: Professor of Analytical Chemistry applied under Cultural heritage at the Department of Analytical chemistry of the University of Granada, Spain. The author contributed to the examination of the Transfguration of Christ, using photography, SEM–EDX, and performed the µRS and µATR-FTIR analyses; and contributed to the interpretation of the datasets, contextualization of data, and writing of the manuscript. RB: Full Professor of Analytical Chemistry at the Department of Analytical chemistry of the University of Granada, Spain. The author contributed to the examination of the painting, sampling, contextualization of the painting, elaboration of tables and fgures, contextualization of data, and participated in the interpretation of the datasets. The author read and approved the fnal manuscript. JDM-R: Professor of Mineralogy at the Department of Mineralogy and Petrology of the University of Granada, Spain. The author provided the interpretation of the mineralogical data. GCh: Professor of Mineralogy Applied under Cultural Herit‑ age at the Department of Earth Sciences of the University of Torino, Italy, Chief Scientist at the Getty Conservation Institute in Los Angeles, CA (director of the Science department for 11 years). The author works now as a freelance con‑ sultant in the feld of Conservation of Cultural heritage. The author read and approved the fnal manuscript. PS: Scientist at the SETI Institute and founder of eXaminart LLC. The author develops miniature X-ray analytical instruments for Space exploration ((e.g. the NASA CheMin XRD instrument inside the Curiosity Mars rover) and portable instruments dedicated to cultural heritage. The author contributed to the examination of the Transfguration of Christ, using pXRD. The author read and approved the fnal manuscript. JLV: Full Profes‑ sor of Analytical Chemistry at the Department of Analytical chemistry of the University of Granada, Spain. The author contributed to the Transfguration of Christ, using photography, SEM–EDX; contributed to the interpretation of the datasets, the contextualization and revision of data. All authors read and approved the fnal manuscript.The main objective of this study is to establish an appropriate method for the characterization of the pigments, materials and structure of the paint layers in a copy of the painting the Transfiguration of Christ by Raffaello Sanzio. A multi-technique approach that combines elemental, molecular and structural analyses and involves optical microscopy (OM), scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDX), mu-Attenuated Total Reflection-Fourier Transform InfraRed (mu ATR-FTIR), mu-Raman spectrometry (mu RS) and non-invasive portable diffractometer (pXRD) was used. Our results revealed that this copy of the Transfiguration was executed with a palette, which includes white lead (cerussite and hydrocerussite), lazurite from lapis lazuli pigment, red and yellow earths (goethite, hematite and lepidocrocite), lead tin yellow, cinnabar, red lake, smalt and bone black, and fillers such as calcite, baryte (an impurity associated to some pigments), and traces of colorless powdered glass. A secondary objective of this research was the application of non-invasive in situ pXRD measurements, which do not require painting sampling and helped to confirm some inconclusive results obtained with other techniques regarding the artist's palette. The results showed the crystalline nature of all the pigments identified, which were known from ancient times and available during the 16th and 17th. Lastly, the used of C-14 accelerator mass spectrometry determined that the canvas date was 1451-1633 AD (with a 95% confidence level). Although the main focus of the work was to improve the analytical methodology to better understand the artist's palette, our results will further help us to explore the authorship of the copy or the school that executed it.Non-Invasive Analytical Techniques Unit EQC2018-004952-PProyecto de investigación FEDER / Junta de Andalucía-Consejería de Economía y Conocimiento / A ‐ HUM ‐ 164 ‐ UGR18

    Evaluation of interpolation methods for generating maps in cultural heritage chemical applications

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    The different non-invasive techniques that have been developed for the study of works of art in Cultural Heritage have become an indispensable tool for researchers and practitioners. In particular, the creation of images showing the spatial distribution of chemical elements and pigments, called maps, helps give a better understanding of the artwork. While high-cost devices can measure the artwork at many positions with high resolution, the cheapest and most common devices are often used manually producing a small number of measurements. The solution is to use interpolation methods. In this article we present a sta- tistical study of the feasibility of using interpolation, we discuss the accuracy of the results and propose the best solutions and a scheme of work. Additionally, we provide all the data developed and programs for future use.MCIN/AEI/10.13039/ 50110 0 011033Project PID2020-118638RB-I00Project A-HUM-164-UGR18FEDER/Junta de Andalucía - Consejería de Economía y ConocimientoGroup FQM-338 (University of Granada)

    Quality of Life and Autonomy in Patients with Intermittent Bladder Catheterization Trained by Specialized Nurses

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    Intermittent bladder catheterization (IBC) involves regular urine draining using a catheter, which is removed immediately after urinary elimination. It allows for the patient's urological health to be managed and their renal function to be preserved, and it promotes autonomy. Compliance with the prescribed number of daily catheterizations, which must be conducted by the patient, and infection prevention measures are crucial. To identify the patients requiring IBC, and to determine their adherence (whether they followed the prescribed guidelines and their difficulty in carrying out the procedure, as well as to assess how the IBC influences their quality of life and state of mind after receiving self-care training from a specialized nurse), we carried out a prospective, multicenter observational study in 24 Spanish hospitals with one month of monitoring and a sample of 99 patients. The sources of information were the patients' clinical records, the King's Health Questionnaire, the Mini-Mental State Examination (MMSE), and the hospital anxiety and depression scale (HADS). Descriptive and bivariate statistics were used to analyses the paired data. After recruitment (n = 99), 79 patients completed the questionnaire at a mean age of 35.2 years (SD = 20.5 years). In total, 53.5% (53) of the sample consisted of men and 32.3% (32) had neurological damage as the reason for prescription; 67% (67.7) performed self-catheterization and 86.7% adhered to the IBC. After one month of monitoring, a statistically significant improvement in quality of life was observed in all criteria, with the exception of personal relationships (p < 0.005), as well as an improvement in anxiety and depression levels (p < 0.001). Patients who require IBC show good adherence to the IBC with a significant percentage of self-catheterization. After one month of IBC, a significant improvement in the patients' quality of life and mood was observed. These results could be attributed to adequate patient training and adequate personalization of the IBC materials by the specialized nurses

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Determinación espectrofluorimétrica de fitohormonas derivadas del indol y del naftaleno

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    Tesis Universidad Granada. Departamento de Química AnalíticaSe realiza el estudio de las propiedades fluorescentes y la puesta a punto de metodología espectrofluorimétrica en disolución y en fase sólida para la determinación en aguas, suelos y formulaciones comerciales de las fitohormonas derivadas del indol: acido indol-3-acetico. acido indol-3-butirico, acido indol-3-propinoico y acido 5-hidroxiindol-3-acetico; y del naftaleno: acido 1-naftilacetico y 1-naftilacetamida. se lleva a cabo la determinación individual de cada una de las fitohormonas asi como la resolución de diferentes mezclas binarias, haciendo uso de la espectrofluorimétria convencional, derivada y en fase sólida
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