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SUMMARY: Even though morphometric and mineral studies related to the guinea pig (Cavia porcellus) skull have been carried out, this study is the first attempt to evaluate all developmental stages of male and female guinea pigs. This study aims to this study is to create 3D modeling of CT images obtained from the skulls of male and female guinea pigs during the developmental period (prepuberty and the period between puberty and adulthood) and following periods (young adulthood and old adulthood), to analyze some biometric bone data such as volume, surface area and length, and to assess the developmental analysis of the mineral matter change in their skulls. The CT-scanned skulls were transferred to 3D Slicer (5.0.2), which is used for 3D modeling. The surface area and volume were calculated by measuring the measurement points on the models. In addition, the XRF device was used to show elemental ratio changes during different developmental stages. According to metric measurements, a gradual increase was observed during the life period. The metric measurements of the skull bone had a higher measurement value in male guinea pigs than in their female counterparts. While Ca/P ratio increased up to the third group and partially decreased in the fourth group in males, it gradually increased from the first group to the fourth group in females. This study revealed that puberty, adulthood and sex were effective in the physical and chemical characterization of skull bone structure in guinea pigs.

Aunque se han realizado estudios morfométricos y de minerales relacionados con el cráneo del cobayo (Cavia porcellus), esta investigación es el primer intento de evaluar las etapas de desarrollo de cobayos machos y hembras. El objetivo de este estudio fue crear un modelado 3D de imágenes de tomografía computarizada obtenidas de los cráneos de cobayos machos y hembras durante el período de desarrollo (prepubertad y el período entre la pubertad y la edad adulta) y los períodos siguientes (edad adulta joven y edad adulta mayor), para analizar algunos datos biométricos de los huesos, como el volumen, la superficie y la longitud, y además, analizar el cambio de materia mineral en sus cráneos durante el desarrollo. Los cráneos escaneados se transfirieron a 3D Slicer (5.0.2), que se utiliza para el modelado 3D. El área de superficie y el volumen se calcularon midiendo los puntos de medición en los modelos. Además, se utilizó el dispositivo XRF para mostrar los cambios en las proporciones elementales durante diferentes etapas de desarrollo. Según mediciones métricas, se observó un aumento gradual durante el período de vida. Las medidas métricas del hueso del cráneo tuvieron un valor de medición más alto en los cobayos machos que en las hembras. Mientras que la relación Ca/P aumentó hasta el tercer grupo y disminuyó parcialmente en el cuarto grupo en los machos y aumentó gradualmente del primer grupo al cuarto grupo en las hembras. Este estudio reveló que la pubertad, la edad adulta y el sexo fueron efectivos en la caracterización física y química de la estructura ósea del cráneo en cobayos.

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The scarcity of nonrenewable resources and the increase in environmental pollution have intensified the search for materials that exhibit specific characteristics and are nontoxic, renewable, and sustainable. Thus, the objective of this work was to produce natural polyphenol adhesives reinforced with rice husk and its ash to increase the mechanical resistance and moisture resistance of the glue line in wood bonded joints. Polyphenols were extracted from the bark of Stryphnodendron adstringens (Mart.) Coville (barbatimão). Adhesives were produced with a 50 % solid and 50 % liquid composition. Rice husk and husk ash underwent X-ray fluorescence analysis (XRF). Adhesives and reinforcement material were characterized by Fourier transform infrared (FTIR) and thermogravimetric analyses (TGA). The adhesives were glued in a mechanical press in specimens made of Pinus elliottii, which were subjected to shear testing of the wet and dry glue line. As a result, the chemical components present in rice husk and its ash positively influenced the properties of the adhesives. The mechanical glue line shear test showed that the adhesive reinforced with rice husk ash did not show a statistically significant difference. However, natural adhesives based on polyphenols from barbatimão strengthened with rice husk and ash showed improved properties, demonstrating how much it pays to use the residue of rice production to reinforce the matrix of tannin adhesives. Thus, it can be determined that reinforcement with rice husk and ash is efficient in improving some properties of natural adhesives based on polyphenols.

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The Moche civilization in Peru developed marvelous metallurgy, primarily using alloys of gold, copper and silver, with the most famous of them called Tumbaga, which resembles pure gold after a depletion process on its surface. However, they also created objects with more standard single-layer alloys or gilding. To distinguish between these techniques in a non-destructive manner is essential. Here, we analyzed a thigh protector, composed of two parts, one seemingly in silver and the other seemingly in gold. The sample was analyzed using X-ray fluorescence measurements integrated with Monte Carlo simulation. The results show that the silver part is formed of a silver-based alloy covered in a corrosion layer, while the gold part is made of Tumbaga. Moreover, for the first time, the gold profiles of different Tumbaga gold objects, from the same burial, were compared, allowing us to obtain information about the standardization of their manufacture.

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Objective. Circulating tumor cells (CTCs) carry crucial information related to the spreading and proliferation of tumors, especially at early stages of the disease. Despite the huge clinical potential held by CTCs in cancer therapy, capture and detection of these cells from the patient's peripheral blood system is rather challenging since CTCs are extremely rare cells. The objective of this paper is, based on Monte Carlo simulations, to propose the detection of immunomagnetically labelled tumor cells by micro-x-ray fluorescence (µ-XRF).Approach. The simulations were carried out with the Monte Carlo N-Particle, version 6.2, (MCNP6.2) code. The model simulates 20µm cancer cell lines and 10µm CTCs tagged with Fe3O4@SiO2spherical nanoparticles of diameters 25 nm, 60 nm and 110 nm. A 17.5 keV monochromatic, micro-focused x-ray beam of diameter 15µm, impinges on cancer cells immersed in a phosphate-buffered saline solution. The simulations also include a polymeric sample holder and a silicon drift detector with a beryllium window and silver collimator.Main results. The results show the dependence of the signal intensity (Fe Kαline) on cell and nanoparticle sizes. Samples containing two and three CTCs were also simulated in particular geometrical configurations. It is presented how the inter-cell distances and cell positions relative to the incident x-ray beam affect the signal. In addition, within the parameters used in the simulations,µ-XRF method provides a minimum detection limit of 9.4 pg of Fe, which corresponds to detecting a single 10µm CTC labeled with 110 nm Fe3O4@SiO2nanoparticles at 6.3% binding.Significance. Theµ-XRF based method proposed in this paper for detecting CTCs, combined with immunomagnetic nanoparticles (NPs), has the potential to be innovative in the field of liquid biopsy.

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BACKGROUND: Essential elements have functions in tumor progression by promoting protumoral cellular processes, such as proliferation, and migration, among others. Obtaining an understanding of how these elements relate to tumor progression processes is of great importance for research. Elemental profile studies in distant tissues, which can be modulated by tumor cells to promote metastasis, have not been sufficiently investigated. The main goal of this study is to evaluate multielemental distribution during tumor progression, focusing on tumor tissue and distant tissues that may be affected. METHODS: Tumor progression in vivo was simulated by inoculating C57BL/6 mice with Lewis Lung Carcinoma (LLC) cells. Samples of the primary tumor and distant tissues were collected during 5 weeks of tumor progression for the control and experimental (tumor-bearing) groups. The biological samples were analyzed using the synchrotron radiation X-Ray fluorescence technique. Data on the concentration of P, S, K, Ca, Mn, Fe, Cu, and Zn in the samples were obtained and statistically analyzed to evaluate the distribution of the elements during tumor progression in the primary tumor as well as distant tissues. RESULTS: It was possible to observe significant changes in the concentrations' distribution of P, S, K, Ca, Mn, Fe, and Cu in distant tissues caused by the presence of tumor cells. It was also possible to detect a greater similarity between tumor tissue (which has the lung as tissue of origin) and a tissue of non-origin, such as the liver, which is an unprecedented result. Moreover, changes in the distributions of concentrations were detected and studied over time for the different tissues analyzed, such as primary tumor, liver and lung, in Control and Tumor groups. CONCLUSIONS: Among other results, this paper could explore the modulation of distant tissues caused by the presence of a primary tumor. This could be achieved by the evaluation of several elements of known biological importance allowing the study of different biological processes involved in cancer. The role of essential elements as modulators of the tumor microenvironment is a relevant aspect of tumor progression and this work is a contribution to the field of tumoral metallomics.

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The purpose of this research was to evaluate performance of an energy-dispersive X-ray fluorescence (XRF) sensor to classify soybean based on protein content. The hypothesis was that sulfur signals and other XRF spectral features can be used as proxies to infer soybean protein content. Sample preparation and equipment settings to optimize detection of S and other specific emission lines were tested for this application. A logistic regression model for classifying soybean as high- or low-protein was developed based on XRF spectra and protein contents. Additionally, the model was validated with an independent set of samples. Global accuracies of the method were 0.83 (training set) and 0.81 (test set) and the corresponding kappa indices were 0.66 and 0.61, respectively. These numbers indicated satisfactory performance of the sensor, suggesting that XRF spectral features can be applied for screening protein content in soybean.

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In recent years, the historical center of Old Havana has been under a serious restoration movement which could increase the heavy metal concentrations in street dusts and thus severely impact humans in the area. Therefore, the aim of this work is to study the heavy metal concentrations, pollution indexes, and health risk assessment of urban road dusts from the city in order to assess if this restoration movement is harmful to the citizens and visitors. Street road dust samples were collected at 33 stations for the determination of some heavy metals (Co, Ni, Cu, Zn, and Pb) concentrations using an X-ray fluorescence (XRF) instrument. The mean concentration values of the elements Co, Ni, Cu, Zn, and Pb were 7.0 mg.kg-1, 60.6 mg.kg-1, 73.6 mg.kg-1, 548.7 mg.kg-1, and 60.8 mg.kg-1, respectively. Zn and Pb showed higher values of the background. The study of the enrichment factor (EF), the pollution index (IP), and the integral pollution index (IPI) showed some stations with high values of contamination near construction places. Zn was identified as the major pollutant and correlated to the biggest construction places of the municipality at that moment. However, the hazard index (HI) and carcinogenic risk (CR) values do not show the risk of getting non-carcinogenic or carcinogenic diseases associated with the analyzed pollutants. Therefore, it was safely concluded that the big reconstruction movement does not represent a health problem.

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Heavy metal contamination in raw materials has spread widely in the United States. The high increased number of recalls in consumer products and the lack of stricter regulations in the raw materials to be used in the jewelry industry have raised concerns among consumers. Studies in low-cost jewelry have shown the presence and high content of heavy metals; this environmental problem led to a child's death after swallowing a charm containing elevated levels of lead (Pb). Exposure to heavy metals, through inhalation, mouth, and skin contact, causes adverse health effects in children and adults. Exposure to lead affects mainly the nervous system and brain development; exposure to cadmium (Cd) causes damage to liver, kidneys, and lungs, and potentially leads to cancer; exposure to nickel (Ni) causes severe dermatitis. Thus, the importance and impact of studies of this nature cannot be overstated. As heavy metal contamination has increased in the United States, this research fills an important knowledge gap between previous studies conducted on low-cost jewelry and fine jewelry. In this study, conducted in the Paso del Norte region, one hundred and forty-three pieces of fine jewelry were evaluated for the presence of heavy metals using X-ray fluorescence (XRF) spectroscopy. Our study showed that 61 samples (42.7 %) exhibited the presence of Ni in the metal alloy, prevailing in jewelry pieces with lower percentage of gold. Eighteen samples showed the presence of Pb in gemstones, 11 pieces of these samples (7.7 % total) had <33.3 % gold (≤10 K); however, none of the samples showed the presence of Pb in the metal alloy. Further research is needed to evaluate the bioaccessibility of Pb in these gemstones, which may pose a potential health hazard to children and adults in the US Paso del Norte region and throughout the world.

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Zinc (Zn) is a micronutrient considered essential to plants which can be supplied through seed treatment. The treatment of soybean [Glycine max (L.) Merr.] seeds with Zn, however, is still not well known as regards the uptake and mobilization dynamics of the nutrient during the germination process. This study aimed to evaluate the uptake and distribution dynamics of Zn applied to soybean seeds at two levels of vigor during germination using X-ray micro-fluorescence spectroscopy (µ-XRF). Zinc treatments corresponded to 0, 2, 4 and 8 g of Zn per kg of seeds. High and low vigor seeds that had been treated were located appropriately so as to promote germination. Zn intensity measurements with µ-XRF were taken in different parts ("regions") of the seeds (seed coat, cotyledon, and embryonic axis) after 8, 16 and 24 h of imbibition and seedlings (primary root, hypocotyl, plumule, cotyledon, and seed coat) after 48, 72 and 96 h of germination. High vigor seeds showed higher Zn intensity in the embryonic axis in the first 16 h, while low vigor seeds showed higher intensity after 24 h. After 48, 72 and 96 h of germination low vigor seedlings showed higher Zn intensity than high vigor seedlings in the primary root. It was concluded that µ-XRF is an efficient technique for identifying variances in the dynamics of Zn uptake and mobilization during the germination of soybean seeds with different vigor levels.

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Currently, copper nanoparticles are used in various sectors of industry, agriculture, and medicine. To understand the effects induced by these nanoparticles, it is necessary to assess the environmental risk and safely expand their use. In this study, we evaluated the toxicity of copper oxide (nCuO) nanoparticles in Danio rerio adults, their distribution/concentration, and chemical form after exposure. This last assessment had never been performed on copper-exposed zebrafish. Such evaluation was done through the characterization of nCuO, acute exposure tests and analysis of distribution and concentration by microstructure X-ray fluorescence spectroscopy (µ-XRF) and atomic absorption spectroscopy (GF-AAS). Synchrotron X-ray absorption spectroscopy (XAS) was performed to find out the chemical form of copper in hotspots. The results show that the toxicity values of fish exposed to nCuO were 2.4 mg L-1 (25 nm), 12.36 mg L-1 (40 nm), 149.03 mg L-1 (80 nm) and 0.62 mg L-1 (CuSO4, used as a positive control). The total copper found in the fish was in the order of mg kg-1 and it was not directly proportional to the exposure concentration; most of the copper was concentrated in the gastric system. However, despite the existence of copper hotspots, chemical transformation of CuO into other compounds was not detected.

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In this study, atomic force microscopy (AFM), microtomography (MCT-2D and MCT-3D) and energy-dispersive X-ray fluorescence spectrometry (EDXRF) were used to generate parameters of the microstructure of the hoof capsule of pigmented and partial albino buffaloes. Seventy-two digits of adult pigmented buffaloes and 16 of partial albino buffaloes were used and equally divided into thoracic and pelvic limbs and medial and lateral claws. Fragments of 10 mm × 10 mm of the dorsal wall, abaxial wall and pre-bulbar sole were collected. The parametric assumptions were tested using a Shapiro-Wilk test (normality). The independent t-test was used to compare the means at a 5% significance level. AFM demonstrated that the hoof surface of pigmented buffaloes presented with higher average surface roughness (Ra) and root mean square roughness (Rms) (p < 0.05) than the hoof surface of partial albino buffaloes. MCT-2D revealed that pigmented buffaloes had extra tubular keratin with a higher density than intratubular keratin. No pores were observed in the hoof capsule of the buffalo digits. MCT-3D demonstrated that pigmented buffaloes have a higher percentage of large and intermediate horn tubules than partial albino buffaloes. However, this difference was not statistically significant. Partial albino buffaloes showed a statistically higher number of horn tubules/mm2 than pigmented buffaloes (p < 0.05). EDXRF revealed a higher amount of sulphur (S) in the hoof capsule of pigmented buffaloes, and the partial albino buffaloes presented a higher number of minerals such as calcium (Ca), potassium (K), zinc (Zn) and copper (Cu).

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Plastics are increasingly being used in consumer products due to its versatility in many applications. However, these plastics may contain inorganic elements that may be harmful to humans. To determine any potential health risk of plastics, it was important to characterize elemental composition of plastics and assess usage patterns. To investigate plastic usage in a typical Jamaican household and to characterize the inorganic elements in consumer plastics using XRF analyzer. About 200 questionnaires were distributed to households to determine the types and quantity of plastics. A total of 130 plastic samples from 7 categories were collected and measured for inorganic elements using handheld XRF. Household plastics were mainly used for storage and personal hygiene products. On average, 10% of plastics were recycled, while 30% were burned. Inorganic elements present in plastic samples were Cl > Ti > Ba > Fe > Zn > Sb > Cr > Br > Cu > V > Pb > As. Elemental concentrations varied based on the category of plastics. Green plastics had the highest concentrations of each type of elements. This study provided useful information on characterizing the different types of elements present in common household plastics. Results from the survey were used to assess participants' attitude and behaviors towards plastics usage and disposal. It was important to obtain a profile of plastics waste from a typical household. This will allow for more targeted strategies to reduce plastics pollution.

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Size is a key factor controlling the rate of dissolution of nanoparticles, such property can be explored for producing controlled release fertilizers. Hence, one can expect the increasing discharge of nanoparticles closer to water streams in the near future. In this study, we employed the model fresh water organism Daphnia magna to investigate the uptake, acute toxicity and depuration of ZnO nanoparticles. The present study shows that the median lethal concentration (LC50) depended on particle size and the presence of surfactant. The LC50 for positive control ZnSO4 (2.15 mg L-1), 20 nm ZnO (1.68 mg L-1), and 40 nm ZnO (1.71 mg L-1) were statistically the same. However, the addition of surfactant increased the LC50 of 40 nm and 60 nm to 2.93 and 3.24 mg L-1, respectively. The 300 nm ZnO was the least toxic nanoparticle presenting LC50 of 6.35 mg L-1. X-ray fluorescence chemical imaging revealed that Zn accumulated along the digestive system regardless the particle size. Finally, contrary to what have been reported by several papers, the present study did not detect any depuration of ZnO nanoparticles in the next 24 h past the exposure assays. Thus, the ability of organisms to expel ingested nanomaterials might be dependent on specific physical-chemical features of such nanomaterials.

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Spectroscopic techniques are commonly used for the non-invasive characterization of the molecular and elemental composition of greenstone archaeological artifacts. The surface topography of these artifacts is greatly influenced by the crafting and polishing techniques employed in their making. However, no study of the effect of roughness on spectra has ever been reported for greenstones. Here we show that infrared, Raman and X-ray fluorescence spectra are strongly influenced by the sample's surface roughness. Spectral changes were seen in both geological (45 jadeite and green stone samples) and archaeological artifacts (12 axe-God pendants); in every case, the variations were more prominent in samples with higher arithmetic average height values. The results show that these changes can affect the interpretation of the spectroscopic data and limit the efficacy of statistical analysis. Consequently, any spectroscopic characterization of this type of samples should be performed preferably in areas with lower values of roughness parameters. Overall, FT-IR appears to be the most advantageous technique to distinguish the differences in mineral composition of this type of samples during in situ studies; its performance was evaluated with an innovative statistical analysis that treats the spectra as functional data. Additionally, the results suggest that confocal Raman spectroscopy is an ideal complementary technique that enhances mineralogical characterization, nevertheless its applicability is limited to laboratory settings.

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In this work, a painting suspected of counterfeiting was analyzed using the synchrotron-based scanning macro X-ray fluorescence (MA-XRF) technique. The canvas has erasures including a signature erasure; however, some visible numbers indicate that the artwork may be from the 17th century. Through the studies' elemental maps, Cl-K and Ca-K were observed, which allowed us to reconstruct the signature present in the painting. Elemental maps of Ba-K, Ti-K, Fe-K, Zn-K, and Pb-K were also obtained from the painting, which made possible to visualize how the pigments based on these elements were used in the creative composition of the painting. In addition to the signature region, a region of the painting with dimensions of approximately 120 mm × 120 mm was investigated by synchrotron radiation induced MA-XRF, while keeping a high spatial resolution and elemental sensitivity. The measurements were carried out at the D09B micro-XRF beamline of the Brazilian Synchrotron Light Laboratory (LNLS), part of the Brazilian Center of Research in Energy and Materials, in Campinas Brazil. The painting was also investigated by SEM-EDS, and FTIR techniques. Those results, in addition to the supporting elemental maps, allowed additional information to be obtained, such as the binders used on the painting.

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High resolution XRF scanning documented inter-annual paleolimnological changes of a Subantarctic periglacial lake, during a process of centennial glacier retreat in King George Island, Antarctica. Two major paleoenvironmental stages were inferred from the combined analysis of elemental, molecular and isotopic biomarkers, with a boundary or transition set at about 3200 yr BP. The first stage was characterized by a relatively low allochthonous organic content, reduced productivity and nitrogen levels. Such paleoenvironmental conditions are interpreted as a terrestrial system under periglacial influence, where material influx was related to erosion process from the melt water discharge, because of the proximity to the Collins Glacier ice cap. After the major Holocene glacier advance dated at about 3500 yr BP, the ice cap retreat led to the formation of Lake Uruguay, which involved in filling processes leading to moraine deposits, proglacial meltwater channels, and lakes next to the land glacier. During the second stage, with the onset of the Current Warm Period, prior to 1900 CE the stabilization of the Zr/Rb ratio within the laminated sediments documented the origin of the lacustrine sedimentation system, with subsequent increases in the sedimentation rate and biomass content (total nitrogen and organic carbon). Time series analyses revealed that the lake displayed variability cycles related to El Niño Southern Oscillation (ENSO), as reflected by high resolution sedimentological proxies for grain size, weathering, allochthonous inputs from the watershed, increase of biomass and productivity, and changes in redox conditions, all of which displayed similar oscillation cycles from 2 to 6 yr. During this periglacial recession and associated eutrophication process, we detected a striking loss in both bacterial specific richness and diversity as inferred from preliminary selected ancient DNA analyses. Thus, the Antarctic warming scenario leading to glacier depletion appears to exert deterioration consequences on the Subantarctic microbial web.

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Geochemical detection using a portable XRF analyser is highly effective for nondestructive surface analysis in archaeological and geological obsidians. The data obtained in rock slabs, fragments, anhydrous nuclei, flaked and ground stone from Sonora, Mexico, were used to select certain analysed elements (Fe, Mn, Zr, Nb, Y, Th, Rb, Sr, Zn) that help to formulate geochemical variation diagrams to identify chemical trends and correlations between the samples. It proves to be an excellent analytical method for the provenance studies of archaeological artifacts. Subsequently, the integration of the obtained data here and their arrangement with the existing chemical analysis of obsidians for different localities of NW Mexico and the SW of the United States will allow for better knowledge of the primary sources of obsidian in the extraction and manufacture of archaeological artifacts.

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Data revealing the phase and chemical compositions of natural black sands from "El Ostional" beach, located in the northern Ecuadorian Pacific coast have been presented. The samples were collected from six points over the shore area of approximately 500 × 40 m2. The data on crystalline phases (iron titanium oxide, orthoclase feldspar and zircon) were determined by X-ray powder diffraction (XRPD), while semi-quantitative chemical analyses of major (Fe and Ti) and trace elements were obtained by X-ray fluorescence spectroscopy (XRF). The phase composition was verified by scanning electron microscopy (SEM), using backscattered electron (BSE) mode and energy dispersive spectroscopy (EDS). These comprehensive data are a contribution to valorize ilmenite-hematite solid solutions from natural resources towards the identification of novel technological applications.

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In this work, 960 réis coins from the period when Brazil was a colony of Portugal were analyzed using the x-ray fluorescence (XRF) spectrometry. The history of these coins, dated between the end of the 17th century and the beginning of the 19th century, had a great influence on the immigration of the Portuguese Prince Regent D. João to Brazil, who arrived in 1808. Bearing in mind the need to expand the timid Brazilian monetary system, the Portuguese crown decided to collect Spanish silver pesos of 8 reales, recoined with a value of 960 réis. The recoinage procedure was carried out using a stamp; therefore, in many cases, it is possible to check the base currency. In this work, were investigated 17 samples of 960 réis coins by XRF, in which the base coin was 8 reales manufactured with raw materials from Mexican mines. In addition to characterizing the elemental composition of the coins, the XRF data were evaluated using multivariate statistical method of Robust Principal Component Analysis (ROBPCA), which was used to classify the coins based on their elemental composition. However, with XRF, elementary information is obtained for a depth of only a few micrometers. One of the essential issues in Ag-Cu metal alloys is the Ag enrichment, which can cause changes to the elemental composition of the surface. Therefore, initially, a study was carried out to verify whether the surface compositions of the coins were altered by the Ag enrichment.

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The compositional characterization of single-use plastics (SUPs), often advertised as biodegradable (B) and oxo-biodegradable (OB), is an important step towards plastic pollution mitigation through the formulation of appropriate (re) use and disposal strategies. We present here the very first study to screen daily SUPs in Mexico through comprehensive characterizations of 33 randomly collected samples (B and OB) of high consumption, with or without food contact, from the markets (n = 80), bakeries (n = 5), pharmacies (n = 5) and near public transportation systems (n = 2) across 16 municipalities of Mexico City, using the polymer composition, metal contents and thermal properties. These SUPs are composed of 85% high-density polyethylene and 15% low-density polyethylene, with significant inorganic additives, and all of them show variable thermal degradation behavior. Among the twenty five different metals identified, most of the SUPs exceed the standard international norms (94/62/EC; EN 13432; 2016/1416; ASTM D6400-04) for Cu, Cr, Mo, Zn, Fe and Pb with the maximum concentrations of 1898 mg/kg, 1586 mg/kg, 95 mg/kg, 1492 mg/kg, 1900 mg/kg and 7528 mg/kg, respectively. Our findings uncovered that the collected SUPs from Mexico City did not have the suitable physicochemical characteristics and they might end up adding to the exponentially growing solid waste in the immediate future. Hence, we recommend the implementation of strict norms to certify the SUPs.