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In this {work}, the X-ray fluorescence technique was employed to characterize the pictorial materials used in two sculptures from the 18th. In addition, Raman spectroscopy was used to characterize the preparation layers used in the sculptures. {The analyzed sculptures} are carved in wood, with gilding and polychrome, and represent the biblical characters, Bathsheba, and King David. The sculptures are property of the Church of \textit{Nossa Senhora do Pilar}, in Duque de Caxias, RJ. XRF {analyzes} were performed using a portable ED-XRF system, which has a low-power X-ray tube (Amptek) with a silver target (Ag) and an SDD detector (Amptek). Raman spectroscopy {analyzes} were performed using the DXR2 Raman microscopy equipment (Thermo Fisher Scientific) with a 785 nm laser source. The results obtained from the XRF and Raman spectroscopy techniques suggest the presence of Gypsum, Calcite, Calcium Sulfate. In addition, the results obtained suggest the presence of the following pigments in the sculptures: Lead white, Titanium White, Lithopone, Ochre, Vermilion, Red Lead and gilding with gold leaf. The studies also showed that the Bathsheba sculpture was probably subjected to some processes of chromatic reintegration over the years due to the heterogeneity of pigments found in the same region

A Berlinda de Aparato do Imperador D. Pedro II é um objeto museológico muito importante para a história do Brasil. Trata-se do veículo imperial mais imponente de todo o período monárquico brasileiro, relacionado não apenas com a imagem do imperador D. Pedro II, mas com todo o Segundo Reinado. A berlinda foi encomendada para a cerimônia de coroação de D. Pedro II, em 1841 e pertence ao acervo do Museu Imperial, localizado na cidade de Petrópolis, Rio de Janeiro, Brasil. Neste trabalho foi analisado a técnica de douramento utilizada nas pinturas decorativas da berlinda. Para a análise do douramento foram aplicadas técnicas de Fluorescência de Raios X (XRF) e Macro Fluorescência de Raios X (MA-XRF). Todas as análises foram realizadas “in situ” utilizando equipamentos portáteis. As medidas de XRF realizadas sobre as folhas de ouro revelaram a presença do elemento-chave cromo. Os resultados combinados das técnicas analíticas utilizadas indicaram a possível utilização de mordente contendo amarelo de cromo como óleo adesivo para fixar as folhas de ouro nas pinturas decorativas. O resultado encontrado está de acordo com o descrito na literatura.

Climate change may shift species outside of their current climatic tolerances, which can be problematic for oceanic islands with limited options for species migration. Their alpine habitats, which represent islands within islands, are a special concern due to high endemism rates. The Canary Islands have two examples for such fragile ecosystems above 2000 m, on La Palma and Tenerife. This study contributes an assessment of the Canary Islands’ climatic habitat for 47 alpine plant species under observed climate change (1959–1989 versus 1990–2019 periods) as well as for future projections (2041–2060 and 2061–2080 periods). We analyzed the contraction of climatic habitats and migration requirements (biotic velocity) for each species to compensate for observed and predicted climate change. Our results suggest that temporary climate refugia exist on Tenerife but are insufficient on La Palma, where habitat loss due to historical climate change has already created an area of significant concern: the Cumbre Vieja Natural Park. On Tenerife, current alpine species can find suitable climate habitats in the caldera area and on the Teide-Pico Viejo volcano. That said, migration paths toward these refugia are long and complex, and human-assisted migration may be required. Species-specific statistics to support such management interventions are provided in this study.

In this work, a commercial micro-XRF mapping equipment was adapted to, through data processing, map the characteristic X-ray transmittance throughout samples. The main difference for conventional tests is the production of characteristic x-rays on a metal base, and its detection on the other side of the sample. The transmittance measure can, therefore, be used to estimate, through equation systems, the layer thickness of each material that makes the sample. Samples of radiographic films were used, where the small thicknesses and the great difference in radiopacity between the materials (polyester and silver) are favorable for data acquisition. The results obtained show thickness maps whose values can be checked by other tools, such as micrometers. Such an approach can be extended to cases with more layers, but this directly implies the number of equations to be solved. The applicability can be used in many areas, depending on conditions of material and acquisition.

The monitoring of ecosystems and forests is an urgent requirement in the current framework of global change. It is particularly necessary on oceanic islands where their rich biodiversity is highly vulnerable, with many narrow-ranged endemic species. Quantifying and mapping forest health through key ecological variables are essential steps for management, but it will also be challenging and may require a lot of resources. Remote sensing has the potential to be a very useful tool to assess the development and conservation status of forests. We assessed the applicability of the light detection and ranging (LiDAR) on the laurel forests of La Gomera, making allometric equations for various measurements of the forest structure, linking field inventory from 2019 and 2017 LiDAR data through standard linear regressions. Decision trees and logistic regressions were also used to assess the performance of LiDAR in the recognition of young-growth and old-growth laurel forests. The obtained allometric models were a good fit in general and their predictions were in line with already known data. Likewise, decision tree and logistic regression to distinguish young-growth and old-growth forests had a similar performance in both cases, with a high to medium-high degree of accuracy. Therefore, LiDAR was revealed to be a useful tool for the monitoring of the laurel forest by the managers.

Para conocer la correcta distribución de la vegeta - ción en un territorio, es fundamental manejar información precisa sobre las variables que la condicionan. Muy probable - mente, el parámetro que condiciona en mayor medida el tipo de vegetación que puede crecer en un lugar es la cantidad de agua de que disponen las plantas. En este sentido, y dejando a un lado las formaciones ligadas a cursos de agua, lagos, etc., el principal origen de este recurso es la lluvia. De esta manera, el estudio de la distribución de la vegetación en cualquier territorio está muy relacionado con el análisis de las precipitaciones que recibe. Para conocer la cantidad de agua de lluvia que recibe una zona se recurre siempre a los datos aportados por las estaciones meteorológicas situadas en la misma. Los datos recogidos por estas estaciones se aplican a una superficie hipotética, homogénea y plana. Esta infor - mación es suficientemente precisa cuando la escala a la que se trabaja es pequeña (1:100.000; 1:50.000), pero cuando se precisa de un mayor detalle, sobre todo en territorios áridos, donde la estructura de la vegetación es abierta y el suelo recibe directamente gran parte de la precipitación, existen condiciones del terreno que condicionan el reparto del agua de lluvia y por tanto el acceso de las plantas a este recurso. Dos de estas variables, quizá las más importantes son la inclinación y la presencia de afloramientos rocosos o de pedregosidad en el suelo. En definitiva, nuestro trabajo consiste en proponer diferentes modelos matemáticos que posibiliten conocer la cantidad real de agua de que disponen las plantas, que denominamos A . Este valor se obtiene a partir de los datos pluviométricos ( P ), relacionándolos con la inclinación del terreno y el porcentaje del mismo ocupado por rocas ( af ). La relación entre la precipitación y la inclinación nos proporciona un valor que denominamos precipitación real ( P ́ ), que es menor cuanto mayor es la inclinación, ya que la cantidad de agua caída debe repartirse en una superficie mayor. La cantidad de afloramiento rocoso aumenta la escorrentía, acumulando agua en las zonas terrosas situadas entre las rocas, por lo que un mayor porcentaje de pedre - gosidad en el suelo conlleva una acumulación de agua en el suelo que lo rodea. De esta manera se proporciona un modelo que permite tanto explicar mejor la distribución de la vegetación en zonas áridas y a escalas grandes (1:25.000 o mayores). Para contrastar el modelo y comprobar su utilidad, se ha realizado un estudio del mismo en diferentes localidades situadas en territorios áridos de la isla de Gran Canaria, una de las Islas Canarias. En esta isla se escogieron 14 lo - calidades situadas en ambientes áridos, con precipitaciones siempre inferiores a 200 mm/m 2 . Entre estas localidades, de condiciones climáticas similares, existe una diversidad vegetal muy importante. La mayor parte están ocupadas por un matorral crasicaule muy abierto dominado por Euphorbia balsamifera , denominado tabaibal de tabaiba dulce, propio de las zonas más desérticas del Archipiélago Canario, y considerado la vegetación potencial de sus zonas áridas e hiperáridas...

For the correct distribution of vegetation in an area, it is essential to manage accurate information on the variables that condition information. Most likely, the parameter that determines further the type of vegetation that can grow in one place is the amount of water available to plants. In this sense, and leaving aside the formations linked to watercourses, lakes, etc., the main source of this resource is the rain. Thus, the study of the distribution of vegetation in any territory is closely related to the analysis of rainfall it receives. To know the amount of rainwater that receives a zone always uses data provided by meteorological stations located in the same. The data collected by these stations are applied to a hypothetical, uniform and flat surface. This information is accurate enough when the scale at which it works is small (1: 100,000, 1: 50,000), but when it requires greater detail, especially in arid areas where the vegetation structure is open and the soil directly receives much of the rainfall, soil conditions exist that determine the distribution of rainwater and therefore access to this resource plants. Two of these variables, perhaps the most important are the inclination and the presence of rocky outcrops or stoniness on the floor. In short, our job is to propose different mathematical models that allow to know the actual amount of water available to plants, we call A. This value is obtained from rainfall data (P), relating to the sloping terrain and the percentage of it occupied by rocks (af). The relationship between precipitation and tilt gives us a value we call the real precipitation (P'), which is lower the greater the inclination, since the amount of rainfall should be distributed over a larger area. The amount of rocky outcrop increases runoff, accumulating water in the earthy areas between the rocks, so a higher percentage of stoniness in soil involves an accumulation of water in the surrounding soil. Thus a model that allows both better explain the distribution of vegetation in arid areas and on large scales (: 25.000 or higher 1) is provided. To test the model and test its usefulness, it has made a study of it in different localities in arid areas of the island of Gran Canaria, one of the Canary Islands. On this island 14 towns located in arid environments, with precipitation always less than 200 mm/m2 were chosen. Among these locations, with similar climatic conditions, there is a very important plant diversity. Most are occupied by a crasicaule very open scrub dominated by Euphorbia balsamífera, called tabaibal de tabaiba dulce, typical of the most barren areas of the Canary Islands, and considered the potential of its arid and hyper-arid vegetation areas. But other situations are occupied by a lush vegetation: the cardonal, almost totally enclosed high scrub, dominated by Euphorbia canariensis, the cardón; and even formations characterized by the presence of a undertree thicket where different woody species such as Olea cerasiformis, wild olive, Juniperus turbinata subsp. canariensis, the sabina, and even the Canary Island pine, Pinus canariensis. These same plant formations appear as potential in areas with higher rainfall, so its presence in these arid areas should be related to some variable affecting the distribution of water resources. For each of these locations was made calculating the amount of water available to plants, obtaining results that meet the alleged contradiction to find different types of vegetation, with different water requirements in the same climatic zone. Thus it is improving the proposed model provides when it comes to study how vegetation is distributed in arid and territories detail scale is checked. It is clear that as we decrease the scale of the study of the distribution of vegetation in any territory, it is essential to increase the parameters analyzed, especially if it comes to analyzing the situation of vegetation in arid, where the structure of vegetation and seasonality of rainfall make the characteristics of the substrate affect significantly to the presence of vegetation way. Given the scarcity of water resources in these ecosystems, any aspect influencing the availability of water for plants will be of great importance for understanding distribution.

El relato de una jornada escolar, con un grupo de niños y niñas que comienzan su escolarización, da pie a un conjunto de reflexiones sobre las relaciones que se establecen entre el alumnado, la maestra y los temas motivo de enseñanza y aprendizaje. La vida en las aulas puede ser analizada desde diferentes ópticas. En este artículo se hace especial hincapié en aquello que tiene que ver con el cuerpo y su motricidad, no tanto para destacar una materia escolar, la educación física, como para reflexionar sobre la influencia y oportunidad de los aspectos biológicos en el conjunto de la acción educativa. Atendiendo las conclusiones, siempre provisionales, que se derivan de estos análisis y reflexiones, proponemos un proyecto educativo para el ámbito corporal en los comienzos de la escolarización que contempla una doble dimensión: su integración en las preocupaciones educativas generales, y su desarrollo como área de expresión y experiencia.

El artículo explica el modo con el que tratamos de formar a los futuros maestros y maestras de Educación Infantil en lo referente al ámbito corporal. Para dar cuenta de este proceso formativo hemos elegido el tema de los juegos motores de oposición, más concretamente una lección sobre el enfrentamiento de uno contra otro. Los juegos motores de oposición, como el resto de los contenidos previstos en la asignatura, encierran un potencial educativo cuyo desarrollo en las aulas de Educación Infantil depende, en buena medida, del conocimiento y saber hacer del profesorado. El artículo muestra las actividades, estrategias y reflexiones que ponemos en marcha para lograrlo.

This work evaluates the chemical composition of pigments used in decorative paintings in the coffin cartonage fragments and linen wrappings of an Egyptian mummy, using X-ray microfluorescence with synchrotron radiation technique. The measures were obtained at the XRF beamline of the National Synchrotron Radiation Laboratory (LNLS). This Roman period female mummy is one of the most important mummies in the National Museum because of its unconventional embalming with disarticulated legs and arms. X-ray fluorescence analysis is a widely used spectroscopic technique in archaeometry for investigating the chemical composition of pigments in manuscripts, paintings, ceramics and other artifacts, metal alloys, and stones. Knowledge of composition allows pigment characterization through major or minor constituents, and makes it possible to establish the provenance, age, and consequently, the authenticity of the artifact.

A utilização das aplicações tecnológicas baseadas nos princípios científicos em raios X durante muito tempo foram utilizadas apenas como ferramentas de diagnósticos médicos. Contudo, a espectroscopia de fluorescência de raios X tem demonstrado possuir uma grande relevância multidisciplinar em inúmeros campos de investigação tais como: meteorítica, química, biologia, meio ambiente, geociências, arqueometria e ciência dos materiais. Buscamos fornecer uma breve síntese seletiva dos recentes trabalhos, buscando assim demonstrar a ampla gama de questões, nas quais ela pode ser aproveitada de maneira produtiva, principalmente devido à sua característica de ser uma técnica não destrutiva. Por fim, serão discutidas aqui as possibilidades de aplicações de forma sucinta e as vantagens específicas da fluorescência de raios X.

The oil industries have as main problem in their activities of formation of scales containing material of the naturally occurring radioactive material (NORM) type on the internal walls of pipes and in some equipment that make up the process lines plant. This NORM can contribute to the exposure of workers during routine activities, either through external exposure, or internal, through inhalation or ingestion. Considering the concern with occupational exposure, environmental impacts and the plant's production capacity, resulting from the formation of the scales, this work characterized samples of scale by means of techniques of x‐ray fluorescence (XRF), x‐ray diffraction (XRD) and high‐resolution gamma spectrometry. The XRF showed concentrations of P, S, Cl, Ca, Mn, Fe, Sr, and Ba as the main elements of the sample; the XRD showed calcite and barite as predominant composition; in the gamma analysis, the concentrations of the activities varied from 104.6 to 1112.6 Bq kg−1 for 226Ra and from 16.4 to 385.2 Bq kg−1 for 228Ra, within the limits set by the International Atomic Energy Agency. The indices radium equivalent activity, absorbed dose rate and annual effective dose indices varied from 128.4 to 1665.9 Bq kg1; 58.4 to 748.0 nGy h−1 and 0.072 to 0.918 mSv y−1, respectively. Only the effective dose values ​​were within the limits established by United Nations Scientific Committee on the Effects of Atomic Radiation, reinforcing the need for continuous monitoring on the platforms and the importance of keeping the radiological protection plan up to date, since the mobilization of NORM increases proportionally with the useful life of the production wells, thus increasing exposure indices. [ABSTRACT FROM AUTHOR]