Complementary analytical methods for analysis of Ag-plated cultural heritage objects
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Archaeometry is an area established in the international community since the 60s, with extensive use of atomic-nuclear methods in the characterization of art, archaeological and cultural heritage objects in general. In Brazil, however, until the early '90s, employing methods of physics, only the area of archaeological dating was implemented. It was only after this period that Brazilian groups became involved in the characterization of archaeological and art objects with these methodologies. The Laboratory of Applied Nuclear Physics, State University of Londrina (LFNA/UEL) introduced, pioneered in 1994, Archaeometry and related issues among its priority lines of research, after a member of LFNA has been involved in 1992 with the possibilities of tomography in archaeometry, as well as the analysis of ancient bronzes by EDXRF. Since then, LFNA has been working with PXRF and Portable Raman in several museums in Brazil, in field studies of cave paintings and in the laboratory with material sent by archaeologists, as well as carrying out collaborative work with new groups that followed in this area. From 2003/2004 LAMFI/DFN/IFUSP and LIN/COPPE/UFRJ began to engage in the area, respectively with methodologies using ion beams and PXRF, then over time incorporating other techniques, followed later by other groups. Due to the growing number of laboratories and institutions/archaeologists/conservators interested in these applications, in may 2012 was created a network of available laboratories, based at http://www.dfn.if.usp.br/lapac. It will be presented a panel of recent developments and applications of these methodologies by national groups, as well as a sampling of what has been done by leading groups abroad.
Objectives: By the end of this offering, participants will be able to: Identify what does and does not define culture; Specify the main drivers of why we need a Nuclear Safety Culture; Detail the primary contributors to LANL's Nuclear Safety Culture history; Explain how LANL's values, behaviors, and actions demonstrate our commitment to a Nuclear Safety Culture; Indicate at least one new piece of knowledge as a result of this course.
Los Alamos National Laboratory (LANL or Laboratory) is one of several national laboratories that support the mission of the United States Department of Energy (DOE), National Nuclear Security Administration (NNSA), Los Alamos Field Office (Field Office). It is located in Los Alamos and Santa Fe Counties, New Mexico. LANL occupies approximately 40 square miles of land owned by the U.S. Government and under the administrative control of DOE/NNSA. Cultural resources management at LANL is the responsibility of the Field Office’s Cultural Resources Program Manager, with the assistance and facilitation of the LANL Environmental Stewardship Group (ES) Cultural Resources Programs (archaeology and historic buildings), which are part of the LANL Environmental Protection and Compliance (EPC) Division. LANL, which is primarily located on the Pajarito Plateau, is extremely rich in cultural resources. Nearly 2,000 archaeological sites have been recorded at LANL, based on the systematic archaeological survey of ~90% of LANL lands. Most of the known sites (~ 85%) date from the Ancestral Pueblo Late Coalition and Classic Periods of around AD 1150 to 1600. The remaining sites date to the Archaic Period (ca. 5500 BC to 600 AD), the Late Developmental and Early Coalition Periods (ca. 900 to 1200), and the Homestead Period (ca. 1890 to 1942).
Reactions of carboxylic acids with lead play an important role in the atmospheric corrosion of lead and lead-tin alloys. This is of particular concern for the preservation of lead-based cultural objects, including historic lead-tin alloy organ pipes. Two initial corrosion products, Pb{sub 3}O{sub 2}(CH{sub 3}COO){sub 2} {center_dot} 0.5H{sub 2}O (1) and Pb{sub 2}O(HCOO){sub 2} (2), had been identified through powder diffraction fingerprints in the Powder Diffraction File, but their structures had never been determined. We have crystallized both compounds using hydrothermal solution conditions, and structures were determined using laboratory and synchrotron single-crystal X-ray diffraction data. Compound 1 crystallizes in P{sub t}, and 2 in Cccm. These compounds may be viewed as inorganic-organic networks containing single and double chains of edge-sharing Pb{sub 4}O tetrahedra and have structural similarities to inorganic basic lead compounds. Bond valence sum analysis has been applied to the hemidirected lead coordination environments in each compound. Atmospheric exposure experiments contribute to understanding of the potential for conversion of these short-term corrosion products to hydrocerussite, Pb{sub 3}(CO{sub 3}){sub 2}(OH){sub 2}, previously identified as a long-term corrosion product on lead-rich objects. Each compound was also characterized by elemental analysis, thermogravimetric analysis and differential scanning calorimetry (TGA-DSC), and Raman spectroscopy.
Constantly evolving technology and techniques within radiation therapy require practitioners to maintain a continuous approach to professional development and training. Systems of performance appraisal and adoption of regular feedback mechanisms are vital to support this development yet frequently lack structure and rely on informal peer support. A Radiation Therapy Performance Appraisal Framework (RT-PAF) for radiation therapists in planning and simulation was developed to define expectations of practice and promote a supportive and objective culture of performance and skills appraisal. Evaluation of the framework was conducted via an anonymous online survey tool. Nine peer reviewers and fourteen recipients provided feedback on its effectiveness and the challenges and limitations of the approach. Findings from the evaluation were positive and suggested that both groups gained benefit from and expressed a strong interest in embedding the approach more routinely. Respondents identified common challenges related to the limited ability to implement suggested development strategies; this was strongly associated with time and rostering issues. This framework successfully defined expectations for practice and provided a fair and objective feedback process that focussed on skills development. It empowered staff to maintain their skills and reach their professional potential. Management support, particularly in regard to provision of protected time was highlighted as critical to the framework's ongoing success. The demonstrated benefits arising in terms of staff satisfaction and development highlight the importance of this commitment to the modern radiation therapy workforce.
The statistical description of ground clutter at an airport and in the surrounding area is addressed. These data are being utilized in a program to detect microbursts. Synthetic aperture radar data were collected at the Denver Stapleton Airport. Mountain terrain data were examined to determine if they may potentially contribute to range ambiguity problems and degrade microburst detection. Results suggest that mountain clutter may not present a special problem source. The examination of clutter at small grazing angles was continued by examining data collected at especially low altitudes. Cultural objects such as buildings produce strong sources of backscatter at angles of about 85 deg, with responses of 30 dB to 60 dB above the background. Otherwise there are a few sources which produce significant scatter. The polarization properties of hydrospheres and clutter were examined with the intent of determining the optimum polarization. This polarization was determined to be dependent upon the ratio of VV and HH polarizations of both rain and ground clutter.
Fractals embody important ideas of self-similarity, in which the spatial behavior or appearance of a system is largely independent of scale. Self-similarity is defined as a property of curves or surfaces where each part is indistinguishable from the whole, or where the form of the curve or surface is invariant with respect to scale. An ideal fractal (or monofractal) curve or surface has a constant dimension over all scales, although it may not be an integer value. This is in contrast to Euclidean or topological dimensions, where discrete one, two, and three dimensions describe curves, planes, and volumes. Theoretically, if the digital numbers of a remotely sensed image resemble an ideal fractal surface, then due to the self-similarity property, the fractal dimension of the image will not vary with scale and resolution. However, most geographical phenomena are not strictly self-similar at all scales, but they can often be modeled by a stochastic fractal in which the scaling and self-similarity properties of the fractal have inexact patterns that can be described by statistics. Stochastic fractal sets relax the monofractal self-similarity assumption and measure many scales and resolutions in order to represent the varying form of a phenomenon as a function of local variables across space. In image interpretation, pattern is defined as the overall spatial form of related features, and the repetition of certain forms is a characteristic pattern found in many cultural objects and some natural features. Texture is the visual impression of coarseness or smoothness caused by the variability or uniformity of image tone or color. A potential use of fractals concerns the analysis of image texture. In these situations it is commonly observed that the degree of roughness or inexactness in an image or surface is a function of scale and not of experimental technique. The fractal dimension of remote sensing data could yield quantitative insight on the spatial complexity and information content contained within these data. A software package known as the Image Characterization and Modeling System (ICAMS) was used to explore how fractal dimension is related to surface texture and pattern. The ICAMS software was verified using simulated images of ideal fractal surfaces with specified dimensions. The fractal dimension for areas of homogeneous land cover in the vicinity of Huntsville, Alabama was measured to investigate the relationship between texture and resolution for different land covers.
Ion Beam Accelerators (IBA) centres have provided researchers with powerful techniques to analyse objects of cultural significance in a non-destructive and non-invasive manner. However, in some cases it is not feasible to remove an object from the field or museum and transport it to the laboratory. In this contributed talk, we present as a manner of a short review, examples of the benefits provided from these techniques in the study of material culture and discuss the initial steps to consider when investigating the feasibility of a compact accelerator that can be taken to sites of cultural significance for PIXE analysis. In particular, we consider the application of a compact, robust 2 MeV proton accelerator that can be taken into the field to perform PIXE measurements on rock art. We detail the main challenges and considerations for such a device.
The era of the International Space Station with its longer duration missions will pose unique challenges to microgravity life sciences research. The Space Station Biological Research Project (SSBRP) is responsible for addressing these challenges and defining the science requirements necessary to conduct life science research on-board the International Space Station. Space Station will support a wide range of cell and tissue culture experiments for durations of 1 to 30 days. Space Shuttle flights to bring experimental samples back to Earth for analyses will only occur every 90 days. Therefore, samples may have to be retained for periods up to 60 days. This presents a new challenge in fresh specimen sample storage for cell biology. Fresh specimen samples are defined as samples that are preserved by means other than fixation and cryopreservation. The challenge of long-term storage of fresh specimen samples includes the need to suspend or inhibit proliferation and metabolism pending return to Earth-based laboratories. With this challenge being unique to space research, there have not been any ground based studies performed to address this issue. It was decided hy SSBRP that experiment support studies to address the following issues were needed: Fixative Solution Management; Media Storage Conditions; Fresh Specimen Sample Storage of Mammalian Cell/Tissue Cultures; Fresh Specimen Sample Storage of Plant Cell/Tissue Cultures; Fresh Specimen Sample Storage of Aquatic Cell/Tissue Cultures; and Fresh Specimen Sample Storage of Microbial Cell/Tissue Cultures. The objective of these studies was to derive a set of conditions and recommendations that can be used in a long duration microgravity environment such as Space Station that will permit extended storage of cell and tissue culture specimens in a state consistent with zero or minimal growth, while at the same time maintaining their stability and viability.
This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as standard dyed textile samples. These selected natural dyes will be used as known references that can be used a guide to identify unknown archaeological dyes. The dyed textile samples were investigated with laser radiation in different wavelengths to detect the best wavelengths for identification each dye. This study confirms that Laser Florescent is very useful and a rapid technique can be used as a non-destructive technique for identification of natural dyes on archaeological textile objects. The results obtained with this study can be a guide for all conservators in identification of natural organic dyes on archaeological textile objects.
Purpose: Adaptive dose-painting-by-number (DPbN) requires a dose-response-mapping (DRM) obtained early in the treatment course. To obtain DRM, voxel-by-voxel tumor dose response needs to be quantified. Our recent study has demonstrated that voxel-by-voxel radio-sensitivity of patient tumor can be determined using tumor-metabolic-ratio measured early during the treatment using FDG-PET images. In this study, the measurements were utilized to construct tumor metabolic control probability (TMCP) and DRM for DPbN. Methods: FDG-PET/CT images of 18 HN cancer patients obtained pre- and weekly during the treatment were used. Spatial parametric images of tumor-metabolic-ratio (dSUV) were constructed following voxel-by-voxel deformable image registration. Each voxel value in dSUV was a function of baseline SUV and delivered dose. Utilizing all values of dSUV in the controlled tumor group at the last treatment week, a cut-off function between the baseline SUV and dSUV was formed, and applied in early treatment days on dSUV of all tumors to model the TMCP. At the treatment week k, TMCP was constructed with respect to the tumor voxel dSUV appeared at the week using the maximum likelihood estimation for all dose levels, and used for DRM construction. Results: TMCPs estimated in the week 2 & 3 have D{sub 50}=11.1∼47.6Gy; γ{sub 50}=0.55∼0.92 respectively with respect to dSUV=0.3∼1.2. The corresponding DRM between tumor voxel dSUV and the expected treatment dose has sigmoid shape. The expected treatment dose are 26∼40Gy (for 95% TMCP) for high sensitive tumor voxels with dSUV=0.3∼0.5; and 65∼110Gy for low sensitive tumor voxels with the dSUV>1.0 depending on the time of the estimation. Conclusion: TMCP can be constructed voxel-by-voxel in human tumor using multiple FDG-PET imaging obtained in early treatment days. TMCP provides a potential quantitative objective of tumor DRM for DPbN to plan the best dose, escalate or de-escalate, in tumor adaptively based on its own radio-sensitivity.
Elemental analysis contributes to authentication (knowing the elemental composition and considering the information about the usual composition of the objects in different historical periods it can be established if the item is original or fake), provenance studies (minor and trace elements indicates ores origin and 'consequently' mines location), (relative) dating of archaeological objects (e.g. for painted items--the chemical recipes for pigments can offer information about the age of objects). The paper gives a general layout for the NIPNE Archaeometry Laboratory's applications using X-Ray Fluorescence (XRF), micro--Proton Induced X-Ray Emission (micro-PIXE), micro-Synchrotron Radiation Induced X-Ray Fluorescence (micro--SR-XRF) methods.
Purpose: To explore the feasibility of improving GBM treatment outcome with temporal-spatial dose optimization of an ordinary differential equation (ODE) that models the differentiation and distinct radiosensitivity between cancer stem cells (CSC) and differentiated cancer cells (DCC). Methods: The ODE was formulated into a non-convex optimization problem with the objective to minimize remaining total cancer cells 500 days from the onset of radiotherapy when the total cancer cell number was 3.5×10{sup 7}, while maintaining normal tissue biological effective dose (BED) of 100Gy resulted from standard prescription of 2Gyx30. Assuming spatially separated CSC and DCC, optimization was also performed to explore the potential benefit from dose-painting the two compartments. Dose escalation to a sub-cell-population in the GTV was also examined assuming that a 2 cm margin around the GTV allows sufficient dose drop-off to 100Gy BED. The recurrence time was determined as the time at which the total cancer cell number regrows to 10{sup 9} cells. Results: The recurrence time with variable fractional doses administered once per week, bi-week and month for one year were found to be 615, 593 and 570 days, superior to the standard-prescription recurrence time of 418 days. The optimal dose-fraction size progression for both uniform and dose-painting to the tumor is low and relatively constant in the beginning and gradually increases to more aggressive fractions at end of the treatment course. Dose escalation to BED of 200Gy to the whole tumor alongside with protracted weekly treatment was found to further delay recurrence to 733 days. Dose-painting of 200 and 500Gy BED to CSC on a year-long weekly schedule further extended recurrence to 736 and 1076 days, respectively. Conclusion: GBM treatment outcome can possibly be improved with a chronic treatment approach. Further dose escalation to the entire tumor or CSC targeted killing is needed to achieve total tumor control. This work is supported by the NSF Graduate Research Fellowship (DGE-1144087)
In this study, we determined the degree of order for 22 Jackson Pollock paintings using the Hausdorff–Besicovitch fractal dimension. Based on the maximum value of each multi-fractal spectrum, the artworks were classified according to the year in which they were painted. It has been reported that Pollock’s paintings are fractal and that this feature was more evident in his later works. However, our results show that the fractal dimension of these paintings ranges among values close to two. We characterize this behavior as a fractal-order transition. Based on the study of disorder-order transition in physical systems, we interpreted the fractal-order transition via the dark paint strokes in Pollock’s paintings as structured lines that follow a power law measured by the fractal dimension. We determined self-similarity in specific paintings, thereby demonstrating an important dependence on the scale of observations. We also characterized the fractal spectrum for the painting entitled Teri’s Find. We obtained similar spectra for Teri’s Find and Number 5, thereby suggesting that the fractal dimension cannot be rejected completely as a quantitative parameter for authenticating these artworks. -- Highlights: •We determined the degree of order in Jackson Pollock paintings using the Hausdorff–Besicovitch dimension. •We detected a fractal-order transition from Pollock’s paintings between 1947 and 1951. •We suggest that Jackson Pollock could have painted Teri’s Find.
We aim to assess the relationship between leisure time activities related to exposure to carcinogenic substances and lung cancer risk in a hospital-based case-control study performed in never smokers. We included never smoking cases with anatomopathologically confirmed lung cancer and never smoking controls undergoing trivial surgery, at 8 Spanish hospitals. The study was conducted between January 2011 and June 2013. Participants were older than 30 and had no previous neoplasms. All were personally interviewed focusing on lifestyle, environmental tobacco smoke exposure, occupational history and leisure time activities (including duration of such activities). Results were analyzed through logistic regression and adjusted also by residential radon and education level. We included 513 never smokers, 191 cases and 322 controls. The OR for those performing the studied leisure time activities was 1.43 (95%CI 0.78–2.61). When we restricted the analysis to those performing do-it-yourself activities for more than 10 years the OR was 2.21 (95%CI 0.93–5.27). Environmental tobacco smoke exposure did not modify this association. The effect for the different lung cancer histological types was very close to significance for adenocarcinoma but only when these activities were performed for more than 10 years. We encourage health professionals to recommend protective measures for those individuals while performing these hobbies to reduce the risk of lung cancer. - Highlights: • Some leisure time activities are associated with the exposure to carcinogenic substances. • These activities are model-making, painting (artistic or not), furniture refinishing or wood working. • Few studies have assessed lung cancer risk due to these hobbies and none in never-smokers. • Leisure activities related to exposure to carcinogenic substances present higher lung cancer risk. • The risk is higher when these activities are performed for more than 10 years.
This study deals with the characterization of mortars collected from bath complex of the Roman villa rustica from an archeological site near Mosnje (Slovenia). The mortar layers of the mosaics, wall paintings and mortar floors were investigated. A special aggregate consisting of brick fragments was present in the mortars studied. The mineralogical and petrographic compositions of the mortars were determined by means of optical microscopy, X-ray powder diffraction and FTIR spectroscopy. Analysis of aggregate-binder interfaces using SEM-EDS revealed various types of reactivity rims. In order to assess the hydraulic characteristics of the mortars, the acid-soluble fractions were determined by ICP-OES. Furthermore, the results of Hg-porosimetry and gas sorption isotherms showed that mortars with a higher content of brick fragments particles exhibited a higher porosity and a greater BET surface area but a lower average pore diameter compared to mortars lacking this special aggregate. - Highlights: {yields} Mineral and microstructural characterizations of brick-lime mortars. {yields} Hydraulic character of mortars in Roman baths complex. {yields} Reaction rims were observed around brick fragments and dolomitic grains. {yields} Higher content of brick particles yielded a higher BET surface area. {yields} Addition of brick particles increased porosity and diminished pore size diameter.
The purpose of this study was to identify the genes induced early in murine oral carcinogenesis. Murine tongue tumors induced by the carcinogen, 4-nitroquinoline 1-oxide (4-NQO), and paired non-tumor tissues were subjected to microarray analysis. Hierarchical clustering of upregulated genes in the tumor tissues revealed an association of induced genes with inflammation. Cytokines/cytokine receptors induced early were subsequently identified, clearly indicating their involvement in oral carcinogenesis. Hierarchical clustering also showed that cytokine-mediated inflammation was possibly linked with Mapk6. Cox2 exhibited the greatest extent (9–18 fold) of induction in the microarray data, and its early induction was observed in a 2 h painting experiment by RT-PCR. MetaCore analysis showed that overexpressed Cox2 may interact with p53 and transcriptionally inhibit expression of several downstream genes. A painting experiment in transgenic mice also demonstrated that NF-κB activates early independently of Cox2 induction. MetaCore analysis revealed the most striking metabolic alterations in tumor tissues, especially in lipid metabolism resulting from the reduction of Pparα and Rxrg. Reduced expression of Mapk12 was noted, and MetaCore analysis established its relationship with decreased efficiency of Pparα phosphorylation. In conclusion, in addition to cytokines/cytokine receptors, the early induction of Cox2 and NF-κB activation is involved in murine oral carcinogenesis.