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1.
Talanta ; 260: 124605, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37146458

RESUMO

In this work we present a methodology for the non-destructive elemental determination of formalin-fixed paraffin-embedded (FFPE) human tissue samples based on the Fundamental Parameters method for the quantification of micro Energy Dispersive X Ray Fluorescence (micro-EDXRF) area scans. This methodology intended to overcome two major constraints in the analysis of paraffin embedded tissue samples - retrieval of optimal region of analysis of the tissue within the paraffin block and the determination of the dark matrix composition of the biopsied sample. This way, an image treatment algorithm, based on R® tool to select the regions of the micro-EDXRF area scans was developed. Also, different dark matrix compositions were evaluated using varying combinations of H, C, N and O until the most accurate matrix was found: 8% H, 15% C, 1% N and 60% O for breast FFPE samples and 8% H, 23% C, 2% N and 55% O for colon. The developed methodology was applied to paired normal-tumour samples of breast and colon biopsied tissues in order to gauge potential elemental biomarkers for carcinogenesis in these tissues. The obtained results showed distinctive biomarkers for breast and for colon: there was a significant increase of P, S, K and Fe in both tissues, while a significant increase of Ca an Zn concentrations was also determined for breast tumour samples.


Assuntos
Neoplasias do Colo , Formaldeído , Humanos , Fixação de Tecidos/métodos , Raios X , Inclusão em Parafina , Biomarcadores
2.
Food Chem ; 397: 133780, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35917781

RESUMO

Fish biofortification with natural ingredients like iodine-rich macroalgae and selenized-yeast is an excellent strategy to enhance the nutritional quality of farmed fish. This study aimed to assess the effect of frozen storage during 12-months on physicochemical quality of biofortified seabream (Sparus aurata) and carp (Cyprinus carpio). Frozen storage reduced iodine content in biofortified seabream fillets (17%), as well as selenium content in biofortified carp fillets (24%). Yet, biofortified fillets still presented enhanced iodine and selenium contents at the end of the storage period. Increased lipid oxidation (3.45 mg MDA kg-1 for seabream and 2.41 mg MDA kg-1 for carp) and decreased water holding capacity (23-29% for seabream and 14-23% for carp) was observed during storage, whereas major changes in colour and texture occurred after 45 days (seabream) and 225 days (carp) of storage. In general, biofortified fish fillets maintained their nutritional value and quality after 360 days of frozen storage.


Assuntos
Carpas , Iodo , Perciformes , Dourada , Selênio , Animais , Alimentos Marinhos/análise
3.
J Trace Elem Med Biol ; 68: 126837, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34385034

RESUMO

BACKGROUND: X ray Fluorescence has been essayed as a suitable technique for the elemental quantification of trace element in human tissues, namely comparison of normal and cancerous tissue. However, accurate results depend on a robust quantification approach, namely correct evaluation of the samples' dark matrix. METHODS: In order to determine the most suitable dark matrix composition for the quantification of such samples using the Fundamental Parameter approach, we have measured several Certified Reference Materials and essayed different dark matrix compositions to achieve the most accurate results. The resulting dark matrix was then applied to normal and tumor ovarian and prostate tissue samples, and the obtained results were compared with the ones obtained with a comparative method using external standard calibration curves. RESULTS: Using a dark matrix composed of 10 % - H, 22 % - C, 3 % - N and 60 % - O yielded the best compromise in accuracy for the light and heavy elements. For the reduced sample size and conditions of this study, for both organs, the concentrations of transition metals decrease in tumor tissues, while the concentration of lighter elements, P and Cl, increases. On the other hand, there are elements that showed different behavior between the two types of tissue, namely Zn and S, that increase in prostate tumor tissue and decrease in ovarian tissue. CONCLUSION: An increase in precision was one of the improvements found with the newly developed method, as the FP-approach contemplates matrix effects and the influence of other elements in the analytes' quantification. Additionally, the determined dark matrix can be employed in any tissue analysis application by means of EDXRF.


Assuntos
Neoplasias , Oligoelementos , Calibragem , Feminino , Humanos , Masculino , Ovário , Espectrometria por Raios X , Oligoelementos/análise , Raios X
4.
Food Chem Toxicol ; 152: 112218, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33882300

RESUMO

Fish fortification with iodine-rich macroalgae (Laminaria digitata) and Selenium-rich yeast is expected to promote nutritional added value of this crucial food item, contributing to a healthy and balanced diet for consumers. However, it is not known if steaming can affect these nutrient levels in fortified fish. The present study evaluates the effect of steaming on nutrients contents in fortified farmed gilthead seabream (Sparus aurata) and common carp (Cyprinus carpio). Fortified seabream presented enhanced I, Se and Fe contents, whereas fortified carp presented enhanced I, Se and Zn contents. Steaming resulted in increased I and Se contents in fortified seabream, and increased Fe and Zn levels in fortified carp, with higher elements true retention values (TRVs >90%). The consumption of 150 g of steamed fortified seabream contributes to a significant daily intake (DI) of I (up to 12%) and Se (up to >100%). On the other hand, steamed fortified carp contributes to 19-23% of I DI and 30%-71% of Se DI. These results demonstrate that steaming is a healthy cooking method, maintaining the enhanced nutritional quality of fortified fish. Moreover, the present fortification strategy is a promising solution to develop high-quality farmed fish products to overcome nutritional deficiencies.


Assuntos
Culinária/métodos , Alimentos Fortificados/análise , Iodo/análise , Valor Nutritivo , Alimentos Marinhos/análise , Selênio/análise , Animais , Aquicultura , Carpas , Temperatura Alta , Dourada , Alga Marinha , Água/química , Leveduras
5.
Food Chem Toxicol ; 140: 111330, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32302721

RESUMO

Developing tailor-made fortified farmed fish is a promising solution to overcome nutritional deficiencies and increase consumer confidence in these products. This study evaluated the supplementation of three fortified diets with I-rich seaweed and selenised-yeast on essential and toxic elements levels in gilthead seabream (Sparus aurata) and common carp (Cyprinus carpio). Fortified diets resulted in increased I, Se and Fe in fish muscle. Biofortified seabream and carp revealed lower Cu and Br. The reduction of fishmeal and fish oil in fortified diets resulted in lower Hg and Cd in seabream muscle. Contrarily, fortified diets increased As and Hg in carp fillets. The consumption of 150 g of fortified seabream enabled a significantly higher contribution to the daily recommended intake (DRI) of I (10%) and Se (76%) than non-fortified fish, whereas fortified carp fulfilled 23% of I DRI and 91% of Se DRI. Moreover, the exposure to Pb decreased with the consumption of biofortified seabream (23-82% BMDL01) and carp (26-92% BMDL01). These results support the strategy of developing eco-innovative biofortified farmed fish using sustainable, natural, safe and high-quality ingredients in feeds, to enable consumers to overcome nutritional deficiencies without significantly increased feed costs.


Assuntos
Ração Animal , Carpas , Suplementos Nutricionais , Iodo/administração & dosagem , Valor Nutritivo , Dourada , Selênio/administração & dosagem , Animais
6.
Ciênc. rural (Online) ; 50(7): e20190395, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1133272

RESUMO

ABSTRACT: The ingestion of foreign bodies, mainly metallic (MFB- metallic foreign body), by cattle is frequent and can lead to death. For diagnostic purposes, reticular pain tests are routinely used, and ferroscopy is still unusual, even as a diagnostic aid. The objective of this study was to validate the application of the GMS 120 Professional BOSCH® metal detector (MD) in the detection of MFB in the bovine species and describe its use in field cases. Fifty MFBs of varying shape, size, and weight were evaluated with an MD, initially on a flat and inert surface, and then in a permanent rumen fistulated cow. Retrospectively, a database from 2000 to 2017 with 122015 cattle was accessed, of which 31865 were examined after the introduction of MD usage in 2013. Fifteen cows positive for reticular pain tests were prospectively evaluated and eight cows were diagnosed with MFB through MD usage. The mean distance for MFB best detection on the inert surface was 4.6 cm. In the fistulated cow, it was not possible to detect any MFBs, regardless of the size or weight of the material. The MFB detection capacity increased with MD use, which can be considered a diagnostic aid in specific situations. Depending on the body condition of the bovine, false negatives may occur with the use of GMS 120 Professional Bosch® metal detector.


RESUMO: A ingestão de corpos estranhos, principalmente metálicos (CEM), pelos bovinos é frequente e pode levar à sua morte. Para fins diagnósticos, as provas de dor reticular são usados de forma rotineira, sendo ainda pouco usual a ferroscopia, mesmo como auxílio diagnóstico. Neste trabalho procurou-se validar a aplicação do detector de metais (DM), marca GMS 120 Professional BOSCH® no reconhecimento de CEM na espécie bovina, além de descrever seu uso em casos a campo. CEM (n=50) de forma, tamanho e peso variados foram selecionados e avaliados com o DM, inicialmente sobre uma superfície plana e inerte e depois in vivo em uma vaca com fístula ruminal. Retrospectivamente, acessou-se um banco de dados dos anos 2000 a 2017 com 122015 bovinos, com 31865 bovinos atendidos após a introdução do DM no ano de 2013. Prospectivamente, avaliaram-se 15 vacas positivas para o teste de dor reticular, oito vacas foram diagnosticadas com CEM através do DM. A distância média para a melhor detecção dos CEM na superfície inerte foi de 4,6 cm. Em vaca fistulada não foi possível detectar nenhum CEM, independentemente do tamanho e peso do material. A campo, após a introdução do uso do DM aumentou a capacidade de detecção dos CEM. O DM pode ser considerado um auxílio diagnóstico em situações específicas. Dependendo da condição corporal do bovino, falsos negativos podem ocorrer com o uso do aparelho GMS 120 Professional Bosch®.

7.
Appl Radiat Isot ; 152: 6-10, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31203095

RESUMO

In this work, we compared the accuracy of gold leaves thickness determination using X-ray Fluorescence (XRF) setups for different X-ray excitation sources. The sources used consisted on: a) direct Bremsstrahlung from an Amptek Mini-X X-ray tube with Rh target, b) partially monochromatized radiation of the same X-ray tube using combination of Al and Ag filters and, c) monochromatic radiation using secondary target, in a portable setup with triaxial geometry. The performance of the used setups was compared using model samples made with gold foil standard reference materials of known thicknesses (1, 2 and 2.5 µm). Thickness determination was based on the selective attenuation that the different energies of a given element of an under-layer undergo in the gilded layer. Ideally, as it can be expected from physics fundamentals, monochromatic radiation is needed for improved accuracy. However, considering the difficulties in using monochromatic radiation in portable instrumentation applicable in Cultural Heritage studies, filtered radiation can also be used for reliable results. Moreover, Monte Carlo simulations of the portable setup with conventional planar geometry were performed for comparison and for future application in more complex samples.

8.
Biol Trace Elem Res ; 187(2): 596-601, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948912

RESUMO

Synchrotron radiation X-ray fluorescence spectroscopy, in conjunction with atomic absorption and Raman spectroscopy, was used to analyze a set of top brand tattoo inks to investigate the presence of toxic elements and hazardous substances. The Cr, Cu, and Pb contents were found to be above the maximum allowed levels established by the Council of Europe through the resolution ResAP(2008)1 on requirements and criteria for the safety of tattoos and permanent makeup. Raman analysis has revealed the presence of a set of prohibited substances mentioned in ResAP(2008)1, among which are the pigments Blue 15, Green 7, and Violet 23. Other pigments that were identified in white, black, red, and yellow inks are the Pigment White 6, Carbon Black, Pigment Red 8, and a diazo yellow, respectively. The present results show the importance of regulating tattoo ink composition.


Assuntos
Substâncias Perigosas/análise , Tinta , Metais/análise , Análise Espectral/métodos , Tatuagem , Cádmio/análise , Cromo/análise , Cobre/análise , Humanos , Chumbo/análise , Mercúrio/análise , Níquel/análise , Espectrometria por Raios X/métodos , Espectrofotometria Atômica/métodos , Análise Espectral Raman/métodos
9.
Theriogenology ; 125: 331-334, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30504074

RESUMO

This study aimed to evaluate the effect of recombinant bovine somatotropin (bST) in combination with progesterone (P4) and estradiol benzoate (EB) on ovarian follicular dynamics using a protocol for estrus and ovulation synchronization in crossbred Bos taurus taurus cows. Twenty-four non-lactating multiparous cows were randomly assigned to two groups: the recombinant bovine somatotropin group (GbST; n = 11) received an intravaginal P4 device (1.5 g), estradiol benzoate (EB = 1.0 mg IM), bST (500 mg SC), and an ovarian ultrasonography (US) on day zero (d0 = beginning of the study); d-cloprostenol (150 µg, IM), US, and P4 removal on d8; 1.0 mg of EB (IM) on d9; and US on d10 and d15. On the other hand, to the control group (GC; n = 13), the same protocol as the GbST was applied, except for the non-receipt of bST on d0. The follicles were measured and evaluated on d0, d8, and d10, as were the corpora lutea (CL) on d15 (using ultrasonography). The effect of the two treatments (GbST vs. GC) on the follicle size, CL (F-test), and ovulation rate (logistic regression) were evaluated. The GbST showed a greater follicle diameter on d10 (14.5 mm) than the GC (12.1 mm; P < 0.03), as well as a greater diameter of CL on d15 (19.7 vs. 16.9 mm, P < 0.01). In addition, in the former, the ovulation rate (90.9 vs. 69.2%, P = 0.09) was observed to be greater. It was concluded that the combination of bST, P4, and EB in synchronization for estrus and ovulation protocols significantly increased the diameter of the preovulatory follicle, produced a higher follicular growth rate, and a greater diameter of the corpus luteum. Additionally, there was a higher percentage of cows with ovulation compared to the group that did not receive bST.


Assuntos
Bovinos , Estradiol/análogos & derivados , Sincronização do Estro/efeitos dos fármacos , Hormônio do Crescimento/farmacologia , Ovulação/efeitos dos fármacos , Progesterona/farmacologia , Animais , Estradiol/administração & dosagem , Estradiol/farmacologia , Feminino , Hormônio do Crescimento/administração & dosagem , Progesterona/administração & dosagem , Distribuição Aleatória
10.
Food Res Int ; 97: 27-36, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28578051

RESUMO

The impacts of climate change on seafood quality, safety and human health are still unknown. The present study investigated the effect of warming on fatty acids and elements content in two tissues (muscle and liver) of the relevant commercial seabass species (Dicentrarchus labrax). After exposing fish to increased seawater temperature for a period of 60days, higher saturated fatty acid (SFA) levels were observed in fish muscle (2.16% increase); whereas lower SFA levels were observed in fish liver (5.42% decrease). On the other hand, monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) contents decreased in both muscle (1.77% and 0.39%, respectively) and liver (10.54% and 8.11%, respectively) of fish subjected to warmer conditions. Additionally, warming promoted changes in fish elemental profiles, leading to significantly higher levels of Cl in the muscle and lower levels of Rb in the liver. Overall, data showed that fatty acids and elemental contents were affected by temperature, though representing small implications to human health. Moreover, this preliminary study highlights the importance of conducting further seafood risk-benefit assessments under climate change contexts.


Assuntos
Bass , Mudança Climática , Alimentos Marinhos/análise , Alimentos Marinhos/normas , Animais , Bass/metabolismo , Bass/fisiologia , Ácidos Graxos/análise , Qualidade dos Alimentos , Modelos Biológicos , Oceanos e Mares , Temperatura
11.
Appl Spectrosc ; 71(3): 432-437, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27694429

RESUMO

In this study, we investigate the capability of energy dispersive X-ray fluorescence (EDXF) spectrometry in a triaxial geometry apparatus as a fast and nondestructive determination method of both dominant and contaminant elements in pharmaceutical iron supplements. The following iron supplements brands with their respective active ingredients were analyzed: Neutrofer fólico (iron gylcinate), Anemifer (iron(II) sulfate monohydrate), Noripurum (iron(III)-hydroxide polymaltose complex), Sulferbel (iron(II) sulfate monohydrate), and Combiron Fólico (carbonyl iron). Although we observe a good agreement between the iron content obtained by the present method and that indicated in the supplement's prescribed dose, we observe contamination by manganese and nickel of up to 180 µg and 36 µg, respectively. These contents correspond to 7.2% and 14.4% of the permitted daily exposure of manganese and nickel, respectively, for an average adult individual as determined by the European Medicine Agency (EMEA). The method was successfully validated against the concentrations of several certified reference materials of biological light matrices with similar concentrations of contaminants. Moreover, we also validated our method by comparing the concentrations with those obtained with the inductively coupled plasma-atomic emission technique.

12.
J Trace Elem Med Biol ; 33: 26-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26653740

RESUMO

In this work, we report the unusual concentration of mercury in the hair of an individual buried in the 18th to mid-19th centuries and the comparison with the elemental composition of other remains from the same individual. Two energy dispersive X-ray fluorescence (EDXRF) setups, one with tri-axial geometry and the second one with micro-beam capabilities and a vacuum system, for light elements detection, have been used. Quantitative evaluation of the obtained spectra were made by fundamental parameters and winAXIL program by compare mode method. The levels of Hg in the hair of buried samples presented a concentration over 5% (w/w), a significantly lower presence of this element in the cranium, and no Hg in the remaining organs. Furthermore, there was no evidence of Hg in the burial soil, which has been also analyzed. From this result, we could conclude that the possibility of post-mortem contamination from the burial surroundings is very unlikely. The obtained results are indicative of the apparent use of a mercury-based compound for medical purposes, most likely lice infestation.


Assuntos
Cabelo/química , Mercúrio/análise , Espectrometria por Raios X/métodos , Adulto , Osso e Ossos/química , Cálcio/análise , Feminino , História do Século XVIII , História do Século XIX , Humanos , Chumbo/análise , Limite de Detecção , Pessoa de Meia-Idade , Fósforo/análise , Padrões de Referência , Solo/química
13.
Microsc Microanal ; 21(3): 606-16, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26149345

RESUMO

The present study characterizes the main deterioration mechanisms affecting the early 17th frescoes of Casa de Fresco, the only known example in Portugal of a semi-underground leisure room richly decorated with a balcony over a water well. Frescoes from the vault are at risk due to salt weathering and biodeterioration. The aim of the research was identification of the deterioration materials, determination of their origin, and their effect on the frescoes before future intervention. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was used to determine salt morphology and microanalysis. The mineralogical characterization was performed by X-ray powder diffraction, complemented with µ-Raman and µ-Fourier transform infrared spectroscopy. Biological assessment was evaluated with optical microscopy and SEM-EDS. Bacterial and fungal isolation and identification were performed using standard culture media and methods according to Bergey's Manual of Systematic Bacteriology and from the Compendium of Soil Fungi. The results show that Ca and Ca-Mg carbonates from the paint renderings are the predominant salt species affecting the site. Bacterial strains from the genera Bacillus and Pseudomonas and fungal strains from the Cladosporium spp. and Penicillium spp. were isolated in the salt formations, within and between the mortar layers. Azurite, malachite, and smalt paint layers are the most affected by the weathering conditions.

14.
Appl Spectrosc ; 69(8): 920-38, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26162347

RESUMO

The most critical steps during the conservation-restoration treatment applied in Moroccan libraries are the deacidification using immersion in a saturated aqueous calcium hydroxide (Ca(OH)2) solution and the consolidation of degraded manuscripts using Japanese paper. The present study aims to assess the efficiency of this restoration method using a multi-analytical approach. For this purpose, three ancient Arabic Moroccan manuscript papers dating back to the 16th, 17th, and 18th centuries were investigated to characterize the paper support and make a comparative study between pre-restoration and post-restoration states. Three structural and molecular characterization techniques including solid-state nuclear magnetic resonance spectroscopy on (13)C with cross-polarization and magic-angle spinning nuclear magnetic resonance ((13)C CP-MAS NMR), attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT-IR), and X-ray diffraction (XRD) were used to elucidate the cellulose main features, to identify the inorganic composition of the papers, and to study the crystallinity of the samples. Inductively coupled plasma atomic emission spectrometry (ICP-AES) allowed us to obtain a qualitative and quantitative characterization of the mineral fillers used in the manufacturing of the papers. Scanning electron microscopy coupled to energy dispersive spectrometry (SEM-EDS) ascertained the state of conservation of the different papers and helped us to study the elemental composition of the samples. After restoration, it was shown that the deacidification improved the stability of papers by providing an important alkaline buffer, as demonstrated using FT-IR and energy dispersive spectrometry (EDS) results. However, XRD and ICP-AES did not confirm the pertinence of the treatment for all samples because of the unequal distribution of Ca on the paper surface during the restoration. The consolidation process was studied using SEM analysis; its effectiveness in restoring torn areas was found to be significant.

15.
Microsc Microanal ; 21(1): 20-55, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25591998

RESUMO

The objects of this study are various local charters (cartas de foral, in Portuguese) granted by Dom Manuel I, King of Portugal (1495-1521), which substituted for medieval ones and were intended to achieve an administrative unification. These are luxuriously illuminated manuscripts, and our study aims at obtaining a better understanding of the gilding and silvering techniques applied to the parchments, in which the forais were written, between 1500 and 1520. The combined use of microscopy and X-ray spectroscopy analyses allowed us to identify the vestigial materials used for making the parchments, including products such as salt (NaCl), lime (CaO), pumice stone (SiO2+Al2O3), and chalk (CaCO3). Chalk was employed as a whitening agent to give the parchment its final color and opacity. Shell-gold and shell-silver mixed in with animal glue or gum binding media were directly applied on type 1 and 3 forais, while very thin gold leaves (<1 µm) were applied over lead-based tempera grounds (50-180 µm thick) in type 2 forais. Silver was always employed in its finest form without a further protective layer (thus its recursive state of corrosion), while gold was used in various alloy grades.

16.
Microsc Microanal ; 21(1): 15-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25158782

RESUMO

The artwork "Smoke Rings: Two Concentric Tunnels, Non-Communicating" by Bruce Nauman represents a case study of corrosion of a black patina-coated Al-alloy contemporary artwork. The main concern over this artwork was the widespread presence of white spots on its surface. Alloy substrate, patina, and white spots were characterized by means of energy-dispersive X-ray fluorescence and scanning electron microscopy with energy-dispersive spectroscopy. Alloy substrate was identified as an aluminum alloy 6,000 series Al-Si-Mg. Patina's identified composition confirmed the documentation provided by the atelier. Concerning the white spots, zircon particles were found on patina surface as external elements.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 1038-46, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25459630

RESUMO

The preservation of manuscripts and archive materials is a serious problem for librarians and restorers. Paper manuscript is subjected to numerous degradation factors affecting their conservation state. This research represents an attempt to evaluate the conservation restoration process applied in Moroccan libraries, especially the alkaline treatment for strengthening weakened paper. In this study, we focused on six samples of degraded and restored paper taken from three different Moroccan manuscripts aged 150, 200 and 800 years. In addition, the Japanese paper used in restoration has been characterized. A modern paper was also analyzed as reference. A three-step analytical methodology based on infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and scanning electron microscopy coupled to energy dispersive spectrometry (SEM-EDS) analysis was developed before and after restoration in order to determine the effect of the consolidation treatment on the paper structure. The results obtained by XRD and ATR-FTIR disclosed the presence of barium sulfate (BaSO4) in all restored paper manuscripts. The presence of calcium carbonate (CaCO3) in all considered samples was confirmed by FTIR spectroscopy. The application of de-acidification treatment causes significant changes connected with the increase of intensity mostly in the region 1426 cm(-1), assigned to the asymmetric and symmetric CO stretching mode of calcite, indicating the effectiveness of de-acidification procedure proved by the rise of the alkaline reserve content allowing the long term preservation of paper. Observations performed by SEM magnify the typical paper morphology and the structure of fibbers, highlighting the effect of the restoration process, manifested by the reduction of impurities.


Assuntos
Manuscritos como Assunto/história , Papel/história , Espectrometria por Raios X , Difração de Raios X , História do Século XVIII , História do Século XIX , História Antiga , Microscopia Eletrônica de Varredura , Marrocos , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
18.
Appl Spectrosc ; 68(11): 1241-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25286343

RESUMO

The present contribution presents a preliminary investigation of the chemical composition with respect to major, minor, trace, and ultratrace elements in several clam species that are frequently used for human consumption in Portuguese markets and worldwide. In order to use a simple and rapid analytical methodology for clam analysis, energy dispersive X-ray fluorescence (EDXRF) spectrometry and total reflection X-ray fluorescence (TXRF) spectrometry were selected as analytical techniques. The analytical capabilities of TXRF spectrometry were evaluated for the determination of minor and trace elements in commercial edible clams. We compared the direct analysis of powdered suspensions (using different sample amounts and dispersant agents) with the analysis of the digested samples for trace element determination. Inductively coupled plasma mass spectrometry analysis of clam digests was also performed to evaluate the analytical possibilities of TXRF spectrometry for trace and ultratrace analysis.


Assuntos
Bivalves/química , Metais/análise , Frutos do Mar/análise , Espectrometria por Raios X/métodos , Animais , Europa (Continente) , Espectrometria de Massas , Turquia , Vietnã
19.
Appl Spectrosc ; 67(12): 1376-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24359650

RESUMO

A case study on a contemporary Indian miniature was carried out through the application of different spectroscopic techniques. Painting support, pigments, and dyes were largely characterized by means of energy dispersive x-ray fluorescence and Raman microspectroscopy directly on the artwork. Regarding golden motifs and silvered areas, for which these techniques have not provided enough information, scanning electron microscopy coupled with energy dispersive x-ray spectroscopy was used as a complementary technique. The painting support was identified as the Bombyx mori silk. Among the colorant matters, several pigments were identified such as chrome yellow, lithopone, hematite, lamp black, mica-titania pearlescent pigment, and tin-based metallic silver, and dyes such as phthalocyanine blue and the recent synthetic pigment red PR9 naphthol AS. All this materials will provide evidence in the support of the contemporary production of the artwork for future studies.

20.
Food Chem Toxicol ; 60: 277-85, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23900006

RESUMO

The effect of cooking methods (boiling, grilling, and roasting) on the proximate and mineral composition, contaminants concentration and fatty acids profile was evaluated aiming to understand the benefits and risks associated to the consumption of the emerging farmed fish meagre (Argyrosomus regius). All the treatments led to lower moisture content. After grilling and roasting, the SFA, MUFA and PUFA contents increased. There was no degradation of EPA and DHA during the culinary processes. Significant retention of minerals in grilled and roasted meagre samples was registered. For Pb and Cd there were no concentration differences between culinary treatments and regarding raw fish. Whereas As level was higher in grilled meagre, total Hg and Me-Hg values were augmented in grilled and roasted meagre. The consumption of meagre is advisable due to the low and healthy fat, high selenium and protein content. Grilling would be the best culinary treatment due to the retention of protein, EPA, DHA and minerals. But as the risk of ingestion of Me-Hg content also increases, based on the risk assessment, intake should not exceed two weekly meals, provided that no other important Me-Hg food source is present in the diet. Otherwise, even this maximum threshold should be lower.


Assuntos
Culinária/métodos , Contaminação de Alimentos/análise , Perciformes , Poluentes Químicos da Água/análise , Animais , Aquicultura , Arsênio/análise , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análise , Mercúrio/análise , Compostos de Metilmercúrio/análise , Portugal , Controle de Qualidade , Medição de Risco , Oligoelementos
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