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1.
Biology (Basel) ; 13(6)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38927326

RESUMO

Indo-Pacific tropical island streams are home to freshwater pipefish (Microphis spp., Syngnathidae). Otoliths were used to uncover life history traits in four species, including a New Caledonian endemic. All four species present the same methodological challenge: their otoliths are small, fragile and mute for growth marks using basic observation tools. Strontium (Sr) is calcium substituent in the mineral lattice, driven by salinity conditions, and thus useful to study diadromous migrations. Synchrotron-based scanning X-ray fluorescence 2D high-resolution mapping allowed us to tackle the global and hyperfine strontium (Sr) distribution. We developed analytical imaging processes to retrieve biological information from otoliths from the data generated via synchrotron analysis. We uncovered plasticity in the life cycle: all species were amphidromous, apart from some freshwater residents from New Caledonia. Understanding life cycle modalities is crucial to categorize species distribution limits and to implement adapted conservation measures, especially when endemic species are at stake. 2D fine-scale images outlined the heterogeneity of Sr distribution: in addition to the trivial Sr incorporation driven by environmental ionic conditions, there is an unusual mosaic arrangement of Sr distribution and we hypothesize that biological control, especially growth during the early life stages, may sometimes overrule stoichiometry. This shows that it is worth studying otolith formation and element integration at imbricated scales, and our methods and results provide a strong basis for future works and prospects in otolith science.

2.
Sci Total Environ ; 941: 173725, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38844241

RESUMO

Trees contribute to bedrock weathering in a variety of ways. However, evaluating their full impact is complicated by a lack of direct observation of unexposed root systems of individual trees, especially when the scale of the analysis goes down to the level of microbiomes. In the present study, we investigated the contribution of tree root systems to bioweathering and soil production at the macro- and microscale. Soil profiles developed under trees on granite bedrock were investigated in two parts of the Sudety Mountains, SW Poland: the Rudawy Janowickie Mountains, and the Stolowe Mountains. Soil profiles were gradually excavated and soil samples collected from pre-defined positions of the root zone: 1) bulk soil, 2) rhizosphere, 3) cracks, 4) topsoil, and 5) control positions. In total, we analyzed 103 samples for soil chemistry and microbiological activity. In addition, we analyzed 19 samples using XRF (X-ray Fluorescence). Four parent rock samples, in the form of thin-sections, were the subject of mineralogical evaluation. Soil analyses included: total organic carbon (C) and nitrogen (N) content, soil pHH2O, soluble iron (Fed), and aluminum (Ald), non-crystalline (amorphous) iron (Feox), and aluminum (Alox). For microbiological analyses, we used a Biolog (EcoPlate) system to determine the functional diversity of soil microorganisms. We evaluated the results on soil chemistry and microbiological activity statistically by principal component analysis (PCA) and redundancy analysis (RDA). Differences between soil sampling positions were assessed using a non-parametric Kruskal-Wallis (K-W) rank sum test and a post-hoc pairwise Dunn test. Trees developed different root architectures, likely shaped by the depth to bedrock and its pre-existing net of fractures and fissures. Tree roots were able to enter bedrock cracks at one study site (at Pstrazna, Stolowe Mountains). The soil profile was too deep for root system penetration at the second study site (Mt Janska, Rudawy Janowickie Mountains, RJM). The rhizospheric soil along the roots had significantly different chemical properties compared to non-rhizospheric soil types. At Mt. Janska, soil differed from the crack soil in terms of Alox (pHolm-adj. < 0.0006) and Feox (pHolm-adj. < 0.004), and from the bulk soil (pHolm-adj. < 0.02) and topsoil (pHolm-adj. < 0.007). In addition, at Pstrazna, the soil differed from the control soil in terms of C (pHolm-adj. < 0.009) and soil pHH2O (pHolm-adj. < 0.0008) and from the topsoil in terms of soil pHH2O. The highest metabolic activity was in cracks at Mt. Janska and in control samples from Pstrazna. In general, the spatial distribution of soil microbial activity, and the weathering that results from that portion of the soil biome, is spatially heterogeneous and appears to be partially determined by the interaction of root growth and bedrock fracture patterns.


Assuntos
Microbiologia do Solo , Solo , Árvores , Solo/química , Polônia , Monitoramento Ambiental , Raízes de Plantas , Rizosfera
3.
Ecotoxicol Environ Saf ; 280: 116519, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38833977

RESUMO

The indiscriminate use of zinc oxide nanoparticles (ZnO NPs) in daily life can lead to their release into soil environment. These ZnO NPs can be taken up by crops and translocated to their edible part, potentially causing risks to the ecosystem and human health. In this study, we conducted pot experiments to determine phytotoxicity, bioaccumulation and translocation depending on the size (10 - 30 nm, 80 - 200 nm and 300 nm diameter) and concentration (0, 100, 500 and 1000 mg Zn/kg) of ZnO NPs and Zn ion (Zn2+) in bok choy, a leafy green vegetable crop. After 14 days of exposure, our results showed that large-sized ZnO NPs (i.e., 300 nm) at the highest concentration exhibited greater phytotoxicity, including obstruction of leaf and root weight (42.5 % and 33.8 %, respectively) and reduction of chlorophyll a and b content (50.2 % and 85.2 %, respectively), as well as changes in the activities of oxidative stress responses compared to those of small-sized ZnO NPs, although their translocation ability was relatively lower than that of smaller ones. The translocation factor (TF) values decreased as the size of ZnO NPs increased, with TF values of 0.68 for 10 - 30 nm, 0.55 for 80 - 200 nm, and 0.27 for 300 nm ZnO NPs, all at the highest exposure concentration. Both the results of micro X-ray fluorescence (µ-XRF) spectrometer and bio-transmission electron microscopy (bio-TEM) showed that the Zn elements were mainly localized at the edges of leaves exposed to small-sized ZnO NPs. However, the Zn elements upon exposure to large-sized ZnO NP were primarily observed in the primary veins of leaves in the µ-XRF data, indicating a limitation in their ability to translocate from roots to leaves. This study not only advances our comprehension of the environmental impact of nanotechnology but also holds considerable implications for the future of sustainable agriculture and food safety.


Assuntos
Bioacumulação , Brassica , Nanopartículas Metálicas , Tamanho da Partícula , Folhas de Planta , Poluentes do Solo , Óxido de Zinco , Óxido de Zinco/toxicidade , Óxido de Zinco/química , Poluentes do Solo/toxicidade , Brassica/efeitos dos fármacos , Brassica/metabolismo , Brassica/crescimento & desenvolvimento , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Nanopartículas Metálicas/toxicidade , Solo/química , Clorofila/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Clorofila A/metabolismo , Nanopartículas/toxicidade
4.
J Imaging ; 10(6)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38921604

RESUMO

X-ray Fluorescence Computed Tomography (XFCT) is an emerging non-invasive imaging technique providing high-resolution molecular-level data. However, increased sensitivity with current benchtop X-ray sources comes at the cost of high radiation exposure. Artificial Intelligence (AI), particularly deep learning (DL), has revolutionized medical imaging by delivering high-quality images in the presence of noise. In XFCT, traditional methods rely on complex algorithms for background noise reduction, but AI holds promise in addressing high-dose concerns. We present an optimized Swin-Conv-UNet (SCUNet) model for background noise reduction in X-ray fluorescence (XRF) images at low tracer concentrations. Our method's effectiveness is evaluated against higher-dose images, while various denoising techniques exist for X-ray and computed tomography (CT) techniques, only a few address XFCT. The DL model is trained and assessed using augmented data, focusing on background noise reduction. Image quality is measured using peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM), comparing outcomes with 100% X-ray-dose images. Results demonstrate that the proposed algorithm yields high-quality images from low-dose inputs, with maximum PSNR of 39.05 and SSIM of 0.86. The model outperforms block-matching and 3D filtering (BM3D), block-matching and 4D filtering (BM4D), non-local means (NLM), denoising convolutional neural network (DnCNN), and SCUNet in both visual inspection and quantitative analysis, particularly in high-noise scenarios. This indicates the potential of AI, specifically the SCUNet model, in significantly improving XFCT imaging by mitigating the trade-off between sensitivity and radiation exposure.

5.
Materials (Basel) ; 17(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38730747

RESUMO

Cementitious materials are used to construct an engineered barrier in repositories for radioactive waste. The cement matrix may contain a variety of organic compounds, some of which are polymeric admixtures used as plasticizers. Superplasticizers (SPs) are highly effective organic cement additives for reducing water amount, increasing workability, homogeneity, plasticity and the non-segregation of mortars and grouts, improving mechanical properties and resistance to destructive environments. SPs in cement could have an impact on the long-term safety of the disposals of radioactive waste. These organic agents can leach from the cementitious matrix into groundwater and may affect the migration behaviour of radionuclides. The detailed chemical composition and other characteristics of the cement (CEM I 42.5 R, Sweden) used for the leaching experiments were evaluated. It contained mainly CaO (52.51 ± 1.37, %), and the surface area of the cement particles was 13.2 ± 1.3 m2/g. An insignificant increase in pH (from 12.6 ± 0.1 to 12.8 ± 0.1) was observed for the leachates over 10 days. A commercially available cement superplasticizer based on polymelamine sulphonate (PMS) Peramin SMF10 (Peramin AB, Sweden) was chosen for the research. The product's chemical composition was analysed using wavelength-dispersive X-ray fluorescence (WD-XRF) spectroscopy, while other physico-chemical properties of the PMS superplasticizer were assessed by Raman spectroscopy and thermo-gravimetric analysis. In aqueous solutions and powders of PMS, the same most intensive features were observed at 774 cm-1 (ring out-of-plane deformation), 977 cm-1 (C-N-C bending, SO stretching) and 1055 cm-1 (C-N=C bending) in the Raman spectra. At up to 270 °C, the polymer was thermally stable. Raman and UV/Vis spectroscopies were used to assess the rate of the alkaline degradation of PMS superplasticizer in different aqueous solutions. No changes were observed in the hydrolytic solutions with any of the above analytical methods over a period of 3 years. The results obtained revealed a good thermal and chemical stability (in highly alkaline media, pH = 9.9-12.9) of the PMS polymer.

6.
Anat Histol Embryol ; 53(3): e13053, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38735036

RESUMO

This study aimed to determine the morphometric measurements anatomically and CT images of skulls of healthy male and female rabbits during postnatal development, to analyse the data statistically and to demonstrate the structural changes in bone. A total of 40 rabbits (20 females and 20 males) were divided into four groups including prepubertal period (group I (0-1 month)), period between adolescence and adulthood (group II (3-5 month)) and later (young adult period as group III (1-3 years) and old adult period as group IV (3-5 years)), with five animals in each group. After the morphometric measurements, the surface area and volume values of the skull were calculated. The skulls were reconstructed using a 3D Slicer (5.0.2), which is used for 3D modelling. The cranial bones in each group were then crushed using a grinder so that the powdered samples were obtained for XRF (X-ray fluorescence technique). The p-value was statistically highly significant between group and gender (p < 0.001). In morphometric measurements, males were generally higher than females. Only PL, GBOC and GNB measurements were higher in females. The p-value between groups (in all measurements), between genders (in TL, GLN, FL, VL, OZB and GBN parameters) and between groups and genders (in TL, DL and VL parameters) was statistically highly significant (p < 0.001). The p-value between the groups, p-value between sexes and p-value between group and sex in Si, P, K, Ca, Ni, Zn, Sr, Sr and Ca/P elements were statistically significant (p < 0.001). Consequently, metric, volume and surface area measurements were taken through 3D modelling of skull bone in prepubertal period (group I), period between adolescence and adulthood (group II) and later (young adult period as group III and old adult period as group IV) of rabbits and the change in the mineral structure during postnatal development and effect of sex on this change were investigated. This might be the first study to assess both metric and mineral changes at four age intervals taken during the life span of rabbits.


Assuntos
Imageamento Tridimensional , Crânio , Tomografia Computadorizada por Raios X , Animais , Coelhos/anatomia & histologia , Coelhos/crescimento & desenvolvimento , Feminino , Masculino , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem , Crânio/crescimento & desenvolvimento , Imageamento Tridimensional/veterinária , Tomografia Computadorizada por Raios X/veterinária , Densidade Óssea
7.
Environ Geochem Health ; 46(6): 202, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696051

RESUMO

Determining the origin and pathways of contaminants in the natural environment is key to informing any mitigation process. The mass magnetic susceptibility of soils allows a rapid method to measure the concentration of magnetic minerals, derived from anthropogenic activities such as mining or industrial processes, i.e., smelting metals (technogenic origin), or from the local bedrock (of geogenic origin). This is especially effective when combined with rapid geochemical analyses of soils. The use of multivariate analysis (MVA) elucidates complex multiple-component relationships between soil geochemistry and magnetic susceptibility. In the case of soil mining sites, X-ray fluorescence (XRF) spectroscopic data of soils contaminated by mine waste shows statistically significant relationships between magnetic susceptibility and some base metal species (e.g., Fe, Pb, Zn, etc.). Here, we show how qualitative and quantitative MVA methodologies can be used to assess soil contamination pathways using mass magnetic susceptibility and XRF spectra of soils near abandoned coal and W/Sn mines (NW Portugal). Principal component analysis (PCA) showed how the first two primary components (PC-1 + PC-2) explained 94% of the sample variability, grouped them according to their geochemistry and magnetic susceptibility in to geogenic and technogenic groups. Regression analyses showed a strong positive correlation (R2 > 0.95) between soil geochemistry and magnetic properties at the local scale. These parameters provided an insight into the multi-element variables that control magnetic susceptibility and indicated the possibility of efficient assessment of potentially contaminated sites through mass-specific soil magnetism.


Assuntos
Monitoramento Ambiental , Poluentes do Solo , Espectrometria por Raios X , Poluentes do Solo/análise , Espectrometria por Raios X/métodos , Análise Multivariada , Monitoramento Ambiental/métodos , Mineração , Portugal , Análise de Componente Principal , Solo/química , Estanho/análise , Fenômenos Magnéticos , Minas de Carvão , Carvão Mineral
8.
Appl Radiat Isot ; 210: 111367, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38805984

RESUMO

In this paper, a comprehensive hybrid K-edge/XRF densitometer (HKED) device model is constructed using MCNP simulation. After the modeling process, a systematic simulation study is conducted to analyze the physical parameters and material selection of KED and XRF. The simulation results reveal that the optimal parameters for the X-ray tube are an X-ray source voltage of 160 kV and a 1 mm Fe filter. The sample should be placed in a vial with an inner diameter of 1.4 cm and an outer diameter of 2 cm. For the KED technique, the determined main parameters are a 1.9 cm Fe filter rod and an inner diameter of 0.08 cm for the collimator. For the XRF technique, the determined main parameters are a 0.01 cm Gd filter and an inner diameter of 0.3 cm for the collimator, with a detector angle of 150°. After selecting appropriate parameters, the average calibration factor Δµ of the KED technique was found to be 3.301 cm2 g-1, with a relative standard deviation (RSD) of 3.36%. Additionally, the comparison between the simulated and calculated values of uranium concentration revealed a minimum measurement error of 0.4%. The minimum detection concentration of KED for uranium solutions is approximately 1 g/L. For plutonium solutions ranging from 0.5 to 20 g/L, linear fitting of the Ka1 net peak area and plutonium concentration showed a coefficient of determination (R2) of 0.999. The detection limit of XRF for plutonium measurement was 2.33✕10-4 g/L. The linear fitting coefficients (R2) of uranium concentration versus K-edge transmission rate and plutonium concentration versus Ka1 net peak area for the hybrid technique in measuring uranium-plutonium mixed solutions are determined as 0.999 and 0.996, respectively, demonstrating the response relationship of the HKED device to uranium and plutonium under different concentrations.

9.
Environ Sci Technol ; 58(21): 9250-9260, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38741559

RESUMO

The potential of recycled iron phosphates (FePs), e.g., vivianites (Fe3(PO4)2·8H2O) and Fe(III)-rich phosphorus (P) adsorbent materials, as phosphorus fertilizer is limited by the strong interaction between Fe and P. In this study, the efficiency of FePs as P fertilizer was explored by applying them as granules or powder in flooded strongly P-fixing soils (acid and calcareous), thereby taking advantage of increased P release induced by reductive dissolution of P-bearing Fe(III) minerals. First, no P diffusion from granular FeP fertilizers into flooded soils was detectable by the diffusive gradient in thin films (DGT) technique and microfocused X-ray fluorescence (µ-XRF) analysis of thin soil sections, in contrast to detectable P diffusion away from granules of soluble triple superphosphate (TSP) fertilizer. On the contrary, powdered FePs demonstrated an excellent increase in extractable P (1 mM CaCl2) in a 120-day incubation experiment in flooded soils. Second, a pot experiment was performed with rice (Oryza sativa) grown in flooded acid and calcareous soils. The fertilizer value of FePs was remarkable when dosed as powder, as it was even up to 3-fold higher than TSP in the acid soil and similar to TSP in the calcareous soil. The beneficial effect of FeP over TSP in the acid soil is attributed to the slow release of P from FePs, which allows to partly overcome P fixation. The promising results of FePs as P fertilizer applied as powders in flooded soils debunk the generally accepted idea that FePs are poor sources of P while demonstrating the importance of the timing of FeP fertilizer application.


Assuntos
Fertilizantes , Oryza , Fosfatos , Fósforo , Solo , Oryza/química , Fósforo/química , Fosfatos/química , Solo/química , Reciclagem , Ferro/química , Agricultura
10.
Materials (Basel) ; 17(10)2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38793354

RESUMO

The co-processing of different wastes as fuels in the manufacture of cement clinker not only meets the objectives of a circular economy but also contributes to the reduction in CO2 emissions in the manufacture of Portland cement. However, waste used as alternative fuels, such as sludge or organic-rich residues, may contain naturally occurring radionuclides that can be concentrated during the combustion process. In this study, the presence of natural radionuclides (radioactive series of uranium, thorium, and 40K) and anthropogenic radionuclides (137Cs) in these wastes has been investigated by gamma spectrometry. Possible relationships between the radioactive content and the obtained chemical composition, determined by X-ray fluorescence, have also been studied by applying a principal component analysis (PCA). The results showed that the wastes with the highest radioactive content were sewage sludge with activity concentrations of 238U and 210Pb of 321 ± 38 Bq kg-1 and 110 ± 14 Bq kg-1, respectively. A correlation between radioactive content and Fe2O3 concentration was also observed. The annual effective dose rates to workers for the ashes estimated from the ash content ranged from 0.0033 mSv to 0.092 mSv and therefore do not pose a risk to workers as they are lower than the 1 mSv per year limit for the general public (DIRECTIVE 2013/59/EURATOM).

11.
Plants (Basel) ; 13(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38611550

RESUMO

Changes in land-use practices have been a central element of human adaptation to Holocene climate change. Many practices that result in the short-term stabilization of socio-natural systems, however, have longer-term, unanticipated consequences that present cascading challenges for human subsistence strategies and opportunities for subsequent adaptations. Investigating complex sequences of interaction between climate change and human land-use in the past-rather than short-term causes and effects-is therefore essential for understanding processes of adaptation and change, but this approach has been stymied by a lack of suitably-scaled paleoecological data. Through a high-resolution paleoecological analysis, we provide a 7000-year history of changing climate and land management around Lake Acopia in the Andes of southern Peru. We identify evidence of the onset of pastoralism, maize cultivation, and possibly cultivation of quinoa and potatoes to form a complex agrarian landscape by c. 4300 years ago. Cumulative interactive climate-cultivation effects resulting in erosion ended abruptly c. 2300 years ago. After this time, reduced sedimentation rates are attributed to the construction and use of agricultural terraces within the catchment of the lake. These results provide new insights into the role of humans in the manufacture of Andean landscapes and the incremental, adaptive processes through which land-use practices take shape.

12.
MethodsX ; 12: 102704, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38651000

RESUMO

In this paper, the preparation of low-cost samples, for the calibration of an energy-dispersive X-ray fluorescence system is presented. The entire procedure is proposed as an undergraduate or postgraduate student laboratory activity, which aims to familiarize students with the procedure of calibration of a spectroscopy-based analytical method through the XRF technique. Furthermore, the use of XRF for the determination of elemental concentrations in samples related to students' interests, was attempted.

13.
Nanotechnology ; 35(28)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38579688

RESUMO

Spatially resolved x-ray fluorescence (XRF) based analysis employing incident beam sizes in the low micrometer range (µXRF) is widely used to study lateral composition changes of various types of microstructured samples. However, up to now the quantitative analysis of such experimental datasets could only be realized employing adequate calibration or reference specimen. In this work, we extent the applicability of the so-called reference-free XRF approach to enable reference-freeµXRF analysis. Here, no calibration specimen are needed in order to derive a quantitative and position sensitive composition of the sample of interest. The necessary instrumental steps to realize reference-freeµXRF are explained and a validation of ref.-freeµXRF against ref.-free standard XRF is performed employing laterally homogeneous samples. Finally, an application example from semiconductor research is shown, where the lateral sample features require the usage of ref.-freeµXRF for quantitative analysis.

14.
J Imaging ; 10(4)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38667993

RESUMO

Scanning micrο X-ray fluorescence (µ-XRF) and multispectral imaging (MSI) were applied to study philately stamps, selected for their small size and intricate structures. The µ-XRF measurements were accomplished using the M6 Jetstream Bruker scanner under optimized conditions for spatial resolution, while the MSI measurements were performed employing the XpeCAM-X02 camera. The datasets were acquired asynchronously. Elemental distribution maps can be extracted from the µ-XRF dataset, while chemical distribution maps can be obtained from the analysis of the multispectral dataset. The objective of the present work is the fusion of the datasets from the two spectral imaging modalities. An algorithmic co-registration of the two datasets is applied as a first step, aiming to align the multispectral and µ-XRF images and to adapt to the pixel sizes, as small as a few tens of micrometers. The dataset fusion is accomplished by applying k-means clustering of the multispectral dataset, attributing a representative spectrum to each pixel, and defining the multispectral clusters. Subsequently, the µ-XRF dataset within a specific multispectral cluster is analyzed by evaluating the mean XRF spectrum and performing k-means sub-clustering of the µ-XRF dataset, allowing the differentiation of areas with variable elemental composition within the multispectral cluster. The data fusion approach proves its validity and strength in the context of philately stamps. We demonstrate that the fusion of two spectral imaging modalities enhances their analytical capabilities significantly. The spectral analysis of pixels within clusters can provide more information than analyzing the same pixels as part of the entire dataset.

15.
Environ Geochem Health ; 46(5): 170, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592402

RESUMO

This study used a new X-ray fluorescence (XRF)-based analytical method with better precision and sensitivity to evaluate the fluorine concentrations in soil. It was hypothesized that the XRF method with a pellet-synthesizing procedure may effectively analyze the fluorine concentrations in soil with ease and reliability. The total fluorine concentrations determined using XRF were compared with those determined using three different types of analytical protocols-incineration/distillation, alkaline fusion, and aqua regia extraction procedures. Among the three procedures, the incineration/distillation procedure did not show reliable precision and reproducibility. In contrast, the total fluorine concentrations determined using the XRF analysis were linearly correlated with those determined using the alkaline fusion and aqua regia extraction procedures. Based on the results of the Korean waste leaching procedure and toxicity characteristics leaching procedure, the leachability of fluorine from soil and waste was not directly related to total fluorine concentrations in soil. Risk assessment also revealed that the fluorine-rich soils did not show non-carcinogenic toxic effects, despite exceeding the regulation level (800 mg/kg) in South Korea for total fluorine concentrations in soil. Our results suggest that XRF analysis in combination with the newly developed pretreatment method may be a promising alternative procedure for easily and rapidly determining the total fluorine concentration in soil. However, further efforts are needed to evaluate fluorine leachability and its associated risks in fluorine-contaminated soils.


Assuntos
Sulfato de Cálcio , Ácido Clorídrico , Ácido Nítrico , Fosfatos , Flúor , Reprodutibilidade dos Testes , Solo , Instalações de Eliminação de Resíduos
16.
Biomed Phys Eng Express ; 10(3)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38604150

RESUMO

We have previously reported the design of a portable109Cd x-ray fluorescence (XRF) system to measure iron levels in the skin of patients with either iron overload disease, such as thalassemia, or iron deficiency disease, such as anemia. In phantom studies, the system was found to have a detection limit of 1.35µg Fe per g of tissue for a dose of 1.1 mSv. However, the system must provide accurate as well as precise measurements of iron levels in the skin in order to be suitable for human studies. The accuracy of the system has been explored using several methods. First, the iron concentrations of ten pigskin samples were assessed using both the portable XRF system and ICP-MS, and the results were compared. Overall, it was found that XRF and ICP-MS reported average values for iron in skin that were comparable to within uncertainties. The mean difference between the two methodologies was not significant, 2.5 ± 4.6µg Fe per g. On this basis, the system could be considered accurate. However, ICP-MS measurements reported a wider range of values than XRF, with two individual samples having ICP-MS results that were significantly elevated (p < 0.05) compared to XRF. SynchrotronµXRF maps of iron levels in pigskin were acquired on the BioXAS beam line of the Canadian Light Source. TheµXRF maps indicated two important features in the distribution of iron in pigskin. First, there were small areas of high iron concentration in the pigskin samples, that were predominantly located in the dermis and hypodermis at depths greater than 0.5 mm. Monte Carlo modelling using the EGS 5 code determined that if these iron 'hot spots' were located towards the back of the skin at depths greater than 0.5 mm, they would not be observed by XRF, but would be measured by ICP-MS. These results support a hypothesis that iron levels in the two samples that reported significantly elevated ICP-MS results compared to XRF may have had small blood vessels at the back of the skin. Second, the synchrotronµXRF maps also showed a narrow (approximately 100µm thick) layer of elevated iron at the surface of the skin. Monte Carlo models determined that, as expected, the XRF system was most sensitive to these skin layers. However, the simulations found that the XRF system, when calibrated against homogenous water-based phantoms, was found to accurately measure average iron levels in the skin of normal pigs despite the greater sensitivity to the surface layer. The Monte Carlo results further indicated that with highly elevated skin surface iron levels, the XRF system would not provide a good estimate of average skin iron levels. The XRF estimate could, with correction factors, provide a good estimate of the iron levels in the surface layers of skin. There is limited data on iron distribution in skin, especially under conditions of disease. If iron levels are elevated at the skin surface by diseases including thalassemia and hemochromatosis, this XRF device may prove to be an accurate clinical tool. However, further data are required on skin iron distributions in healthy and iron overload disease before this system can be verified to provide accurate measurements.


Assuntos
Ferro , Pele , Espectrometria por Raios X , Ferro/análise , Pele/metabolismo , Animais , Suínos , Espectrometria por Raios X/métodos , Espectrometria por Raios X/instrumentação , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Espectrometria de Massas/métodos , Cádmio/análise
17.
Int. j. morphol ; 42(2)abr. 2024.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1558130

RESUMO

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.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38478009

RESUMO

Herbs and spices are known to be prone to food fraud and accurate analytical tools are needed to detect adulterants. Amongst the potential adulteration, dilution with bulking agents has regularly been reported, especially with inorganic materials such as talc or brick powder. Energy Dispersive X-Ray Fluorescence (ED-XRF) spectrometry is a well-established non-destructive analytical technique for qualitative and quantitative elemental analysis of a wide variety of samples. ED-XRF was here evaluated for the detection of inorganic adulterants in turmeric, paprika and oregano, which were selected as representative for the herbs & spices food category. Magnesium, silicon, and calcium were identified as elements to detect talc, soapstone, brick/clay powder, and chalk inorganic adulterants. ED-XRF successfully detected adulterated samples when spiked down to 5% (w/w) in the selected herbs and spices. With its ease-of-use and speed, ED-XRF is well adapted for the monitoring of inorganic adulteration of herbs and spices along the supply chain.


Assuntos
Curcuma , Contaminação de Alimentos , Origanum , Espectrometria por Raios X , Curcuma/química , Contaminação de Alimentos/análise , Origanum/química , Especiarias/análise , Capsicum/química , Análise de Alimentos , Compostos Inorgânicos/análise
19.
J Hazard Mater ; 469: 133903, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38430601

RESUMO

Biochar, an environmentally friendly material, was found to passivate lead (Pb) in contaminated soil effectively. This study utilized spectroscopic investigations and partial least squares path modeling (PLS-PM) analysis to examine the impact of coconut-fiber biochar (CFB) on the translocation, accumulation, and detoxification mechanisms of Pb in soil-rice systems. The results demonstrated a significant decrease (p < 0.05) in bioavailable Pb concentration in paddy soils with CFB amendment, as well as reduced Pb concentrations in rice roots, shoots, and brown rice. Synchrotron-based micro X-ray fluorescence analyses revealed that CFB application inhibited the migration of Pb to the rhizospheric soil region, leading to reduced Pb uptake by rice roots. Additionally, the CFB treatment decreased Pb concentrations in the cellular protoplasm of both roots and shoots, and enhanced the activity of antioxidant enzymes in rice plants, improving their Pb stress tolerance. PLS-PM analyses quantified the effects of CFB on the accumulation and detoxification pathways of Pb in the soil-rice system. Understanding how biochar influences the immobilization and detoxification of Pb in soil-rice systems could provide valuable insights for strategically using biochar to address hazardous elements in complex agricultural settings.


Assuntos
Oryza , Poluentes do Solo , Oryza/metabolismo , Cocos , Chumbo/análise , Solo/química , Poluentes do Solo/metabolismo , Carvão Vegetal/química , Cádmio/metabolismo
20.
Biol Trace Elem Res ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489123

RESUMO

For understanding trace element dynamics in tissues, methods for analyzing elemental distribution and localization without destroying tissue structures and cell arrangements are desired. Synchrotron radiation X-ray fluorescence (SR-XRF) analysis is one of the non-destructive and multi-element simultaneous analyses. The kidney is the major excretion pathway of cesium (Cs) taken into the body, and an understanding of cesium distribution in the kidney would be useful for establishing technology to facilitate the excretion of radioactive Cs from the body due to nuclear disasters. In the present study, the distribution of cesium and trace elements, such as iron (Fe) and zinc (Zn), corresponding to the kidney structure was examined in Cs-administered mice by SR-XRF imaging with high-energy excitation X-rays (40 keV). By beam scanning with a 200-µm square beam, clear Cs images corresponding to the renal layer structure were obtained for the renal specimen at the early phase after Cs administration with the mean renal Cs concentration of 24.1 ± 3.2 µg/g. Cs was distributed mainly in the medulla and the outer stripe of the outer medulla located in the center area of the kidney. Unlike the Cs distribution, endogenous Fe and Zn tended to be lower in the medulla than in the outer stripe of the outer medulla and the cortex. This method is effective for analyzing Cs distribution because it can simultaneously analyze the distribution of endogenous trace elements.

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