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Localized cutaneous argyria is a rare condition in which the skin changes into blue-grey spots due to the absorption of silver. The lesions need to be differentiated from other pigmentary disorders and require radiographic and histological examination for more accurate diagnosis. Scanning electron microscopy and energy dispersive x-ray spectroscopy can be a confirmatory tool in the evaluation of silver elements in biopsy tissue. This report shows the localized cutaneous argyria in earlobe of a 21-year-old woman who wears silver earrings for 10 years. (Ann Dermatol 31(6) 666∼668, 2019)

Agradecimentos: This study was supported by grants from the São Paulo Research Foundation, Brazil (FAPESP #2011/21670-9). The authors of this article certify they have no proprietary, financial, or other personal interest of any nature or kind in any product, service, and/or company that is presented in this article Abstract: The purpose of this study was to evaluate the surface roughness (Ra), and the morphology and composition of filler particles of different composites submitted to toothbrushing and water storage. Disc-shaped specimens (15 mm × 2 mm) were made from five composites: two conventional (Z100™, and Filtek™ Supreme Ultra Universal, 3M), one "quick-cure" (Estelite E Quick, Tokuyama), one fluoride-releasing (Beautiful II, Shofu), and one self-adhering (Vertise Flow, Kerr) composite. Samples were finished/polished using aluminum oxide discs (Sof-Lex, 3M), and their surfaces were analyzed by profilometry (n = 5) and scanning electron microscopy (SEM; n = 3) at 1 week and after 30,000 toothbrushing cycles and 6-month water storage. Ra data were analyzed by two-way analysis of variance and Tukey's test (a = 0.05). Filler particles morphology and composition were analyzed by SEM and X-ray dispersive energy spectroscopy, respectively. Finishing/polishing resulted in similar Ra for all the composites, while toothbrushing and water storage increased the Ra of all the tested materials, also changing their surface morphology. Beautifil II and Vertise Flow presented the highest Ra after toothbrushing and water storage. Filler particles were mainly composed of silicon, zirconium, aluminum, barium, and ytterbium. Size and morphology of fillers, and composition of the tested composites influenced their Ra when samples were submitted to toothbrushing and water storage FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Voor een inductief gekoppeld plasma zijn de matrixeffecten onderzocht voor matrixoplossingen met een enkele matrixcomponent (Na of Ca) en voor oplossingen met twee matrixcomponenten (Na plus Ca). Daarbij werd gebruik gemaakt van een ultrasone verstuiver en het plasma werd op de 'klassieke' manier bekeken (radiaal). Correctie voor matrixeffecten werd uitgevoerd door het gebruik van een interne standaard op twee manieren. Bij de ene manier werd het analietsignaal gedeeld door het signaal van de interne standaard (internal standard ratio method) en bij de tweede, nieuwe manier werd een proportionele correctie uitgevoerd in relatie tot het signaal van de interne standaard. Deze manier werd dan ook 'proportional correction' genoemd. Als interne standaardelementen werden yttrium en scandium gebruikt. De beste correctie werd verkregen met behulp van proportionele correctie, zowel voor enkelvoudige matrixcomponentsystemen als voor het tweevoudige matrixcomponentsysteem.

The quality of the dentin root is the most important factor for restoration resin sealing and drives the outcome of endodontic treatment. Objective This study evaluated the effect of different filling pastes and cleaning agents on the root dentin of primary teeth using Fourier-transformed Raman spectroscopy (FT-Raman), micro energy-dispersive X-ray fluorescence (µ-EDXRF) and scanning electron microscopic (SEM) analysis. Material and Methods Eighty roots of primary teeth were endodontically prepared and distributed into 4 groups and filled according to the following filling pastes: Control-no filling (CP), Calen®+zinc oxide (CZ), Calcipex II® (CII), Vitapex® (V). After seven days, filling paste groups were distributed to 4 subgroups according to cleaning agents (n=5): Control-no cleaning (C), Ethanol (E), Tergenform® (T), 35% Phosphoric acid (PA). Then, the roots were sectioned and the dentin root sections were internally evaluated by FT-Raman, µ-EDXRF and SEM. Data was submitted to two-way ANOVA and Tukey tests (α=0.05). Results Regarding filling pastes, there was no significant difference in organic content. CP provided the lowest calcium values and, calcium/phosphoric ratio (Ca/P), and the highest phosphoric values. For cleaning agents there was no difference in organic content when compared to the C; however, T showed significantly higher calcium and Ca/P than PA. All groups showed similar results for phosphorus. The dentin smear layer was present after use of the cleaning agents, except PA. Conclusion The filling pastes changed the inorganic content, however they did not change the organic content. Cleaning agents did not alter the inorganic and organic content. PA cleaned and opened dentin tubules.

The change in the implant microstructure during handling may reduce the potential of surface treatment on the osteoinduction and, therefore, on the osseointegration. The aim of this study was to evaluate by energy-dispersive X-ray spectroscopy (EDX) the effect of insertion torque and pullout test on the microstructure of dental implants with different shapes. Four shapes of implants (n=8) were selected: conical with surface treatment (COTS), cylindrical with surface treatment (CTS), cylindrical with double surface treatment (CTSD) and cylindrical with machined surface (CSU). Before and after performing the mechanical tests, the screw surfaces were subjected to analysis of chemical composition by EDX. The results obtained by the microstructural analysis showed presence of three main chemical elements: Ti, C and O. There was a significant change in the concentration of Ti and C. The implant with double surface treatment (CTSD) showed the greatest Ti reduction and the greatest C increase. It may be concluded that the mechanical manipulation may alter the implant surfaces as regards their microstructure. Therefore, surgical planning should take into consideration the choice of surface treatment because the characteristics of the implants may be modified as they are inserted and removed from the bone site. A alteração da microestrutura do implante durante seu manuseio pode reduzir o potencial do tratamento superfícial na osteoindução e consequentemente na osseointegração. O objetivo deste estudo foi avaliar o efeito do torque de inserção e do ensaio de arrancamento, na microestrutura de implantes odontológicos de diferentes formatos, por meio de espectometria de energia dispersiva de raios-X (EDS). Para a realização do estudo foram selecionados quatro modelos de implantes Conexão(r) (n=8): Cônico com tratamento de superfície (COTS), Cilíndrico com tratamento de superfície (CTS), Cilíndrico com duplo tratamento de superfície (CTSD) e Cilíndrico com superfície usinada (CSU). Antes e após a realização dos ensaios mecânicos, os parafusos foram submetidos à análise da composição química de suas superfícies, por meio de EDS. Os resultados obtidos com a análise microestrutural demonstraram a presença de três elementos químicos principais: Ti, C e O. Foi verificada alteração estatisticamente significante na concentração dos elementos Ti e C. O implante com duplo tratamento de superfície (CTSD) foi o que apresentou a maior redução do Ti e maior aumento do C. A partir dos dados obtidos foi possível concluir que a manipulação mecânica pode alterar a superfície dos implantes quanto à sua microestrutura. Sendo assim, o planejamento cirúrgico deve levar em conta a escolha do tratamento de superfície, pois uma vez que o implante é inserido e removido do leito ósseo suas características podem ser alteradas.

To obtain satisfactory sample melting i. e. a positive result of the JIIS test it is necessary to determine conditions glass disk preparation for each type of sample as pre characteristics of glass disk e. g. particle size, homogeneity of the sample – flux mixture, composition of the mixture for melting, melting temperature and time as well the temperature regime during the melting procedure were examined for samples of iron ores sinters, mixture for sinters and blast furnace slags. The samples and subsamples, in particular phases of the procedure of glass disk preparation were studied by x – ray diffraction and electron probe microanalysis. A Debye Scherr camera PW 1024 Philips and a electron – probe microanalyses JOEL JXA 50A were used. A conclusion about the quality of the procedure of glass disk preparation can be drawn from the presence or absence of the lines of flux mixture components in Debye Scherrer photographs or from distribution of analyte on the x – ray image. To achieve a satisfactory glass disk quality is necessary to establish uniformity of particle size in the mixture for melting, to reach high homogeneity of the sample – flux mixture, to define optimum mass participation of each component in the mixture for melting and define optimum time, temperature and regime of melting. In these conditions are not fulfilled, non – transparence segration of unreached components on the surface as well as breaking and husking on the edges of glass disk will appear. All results were analyzed mathematically.

Made available in DSpace on 2014-06-11T19:24:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-03-24Bitstream added on 2014-06-13T18:51:41Z : No. of bitstreams: 1 lima_jpm_me_arafo.pdf: 3908479 bytes, checksum: 1c7f63e885d8dafaeb577071612f7aa7 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Atualmente, vários novos materiais estéticos são lançados no mercado odontológico destinados especificamente à confecção de restaurações diretas. Embora tais compósitos apresentem bons resultados clínicos, o que garantem ser indicados nas regiões anterior e posterior, ha a necessidade de comprovações adicionais para que se possam ser utilizados com segurança. As informações disponíveis de cada material recém introduzido ainda trazem duvidas sobre sua real composição e sobre suas propriedades físicas e mecânicas, gerando confusão para o clinico, que pode estar ciente ou não de qual resina melhor atende as necessidades de cada paciente. O conhecimento dimensional do conteúdo inorgânico dos sistemas de resinas compostas ainda e o responsável pela classificação dos mesmos e parecem estimar sobre suas propriedades mecânicas. Assim, nos propusemos a (1) estudar através de ampla e profunda revisão sistemática da literatura, a influencia das partículas inorgânicas nas propriedades físicas, químicas e mecânicas de resinas compostas e; (2) descrever a morfologia e a composição química das partículas inorgânica das resinas compostas atuais, como forma de dotar o clinico de um parâmetro de comparação entre os materiais restauradores resinosos, e de auxiliá-lo na indicação deste material mediante situação clínica. Na primeira etapa de nosso estudo, foram determinados os critérios de inclusão e exclusão, e estabelecida a estratégia de busca – palavras-chave e limites de assuntos, em varias combinações – dos estudos laboratoriais nas principais bases de dados eletrônicas (ISI – Web of Science, Medline, Biblioteca Cochrane, SciELo, Lilacs e Biblioteca Digital de Teses – Portal Capes), e outras fontes de informação. Currently, dozens of new aesthetic materials are launched on the dentistry market designed specifically to the confection of direct restorations. Although such composite show good clinical results, which guarantees be given in anterior and posterior regions, there is a need for additional evidence so that it can be used safely. The information available of each newly introduced material also brings questions about their real composition and on its physical and mechanical properties, creating confusion for the clinician, which may be or not aware of resin which best meets the necessities of each patient. The dimensional knowledge of the inorganic content of the composed resin systems also is responsible for the classification of the same ones and seems estimate on its mechanical properties. Thus, we proposed (1) to study through extensive and meticulous systematic review of literature, the influence of inorganic particles in the physical, chemical and mechanical properties of composite resins and; (2) to describe the morphology and chemical composition of the inorganic particles of current composite resins, as a way of giving the clinician with a parameter of comparison among the resinous restorative materials, and of assisting it in the indication of this material through of clinical situation. In the first stage of our study, the criteria of inclusion and exclusion had been determined, and established the strategy of search – keywords and limits of subjects, in some combinations – of the laboratory studies in the main electronic databases ((ISI – Web of Science, Medline, Biblioteca Cochrane, SciELo, Lilacs and Digital Library of Theses – Portal Capes), and others sources of information. Of the 138 abstracts located, only 59 were selected (most located on Pubmed) being in accordance with the pre-established criteria.

Model samples prepared from starch, Alkaloid, Skopje were used in investigation. After 2, 5 hours of irradiation an increase in the number of grains in small-sized fraction was noted which directly influenced the accuracy and reproducibility of X -ray relative intensity measurements.

Briquetted samples for control analysis by emission spectrometry have to be compact products with smooth surface and good mechanical resistance. To obtain such briquettes the optimal conditions of preparation should be determined for each type of sample (iron ore, sinter, etc.). Two parameters influencing the briquette quality - pressure and pressure time were examined using an originally developed VDM device. The optimal conditions for the preparation of briquetted iron ore and sinter samples were determined.

In this paper the behaviour of boric acid as binder was investigated. On basis of debyegrams and secondary electron micrographs radiolytic changes of boric acid were proved. Debyegrams of sample of boric acid showed that spottiness and prefered orientation were enhanced after exposure of sample to x-Rays. In secondary electron micrographs interruption of regularity of initial lamellar structure after iradiation of boric acid sample coud be seen as broken lamellas and appearance of round-shaped crystals with adhering particles. These radiolytic cahanges have as a result and increased briquetted porosity and are considered to constitute limiting factor for longer use of smples prepared with boric acid as binder.

A Monte Carlo model has been developed, using the EGS4 code, to aid the design and optimization of a polarized source for in vivox-ray fluorescence(XRF) analysis of platinum (Pt). The modeled code is based on a 300 kV clinical x-ray therapy unit at Singleton Hospital. The code handles five individual components (x-ray tube, filter, polarizer, sample, and detector) which the user assembles as needed, thus allowing the facility for simulation of a wide variety of XRF systems. For each component, all the physical dimensions and materials involved are set by the user. The model includes polarized photon transport modification, K-edge fluorescent photon transport modification and K-edge sampling method for mixtures (a facility previously available only for simple compounds). It incorporates a variance reduction technique (forcing photon interaction) and uses random number generator called RANMAR. Also EGS4PICT (The EGS4 Shower Display System for PC) is built in to display a shower picture at every stage of simulation. The selected polarizermaterials tested are C, Al, Fe, Cu, Sn, and Pb. The material shape and thickness are investigated. The secondary beam collimator diameter, length, and material are also studied. Results are compared with analytical models and experiment.

For better understanding and interpretation of the observed deviation in results of measurement of relative intensity of analytical lines FeK , CaK and SiK in samples of limonite iron ore and sinter mixture specially prepared samples were studied. Limonite iron ores and sinter mixure were ground, separated by sieving into five fractions (size between 200  m and < 50  m), homogenized and formed into briquettes without or with binder. In the same way were prepared samples of mixture of different fractions, mixed in ratios 3 : 1, 1: 1 and 1: 3. All measurements were made on a sequential semiautomatic X-ray spectrometer, diffractometris system and scanning electron probe microanalyser. The results obtained showed that changes in relative intensity were due not only to component participation in each fraction but also to the phase component participation in each fraction but also to the phase composition of grain, its behaviour during the briquetting process, segregation rate and the tendency towards agglomeration and formation of stuck particles.

The influence of heterogeneity on the measurement of relative intensities by the method of X-ray emission spectrometry was studied in prepared model samples. The results obtained enabled the explanation of irregularities observed in the measurement of FeK-alpha, SiK-alpha and CaK-alpha lines in real samples. For the sake of better understanding of the influence of grain size composition mixtures of different sample fractions were studied. Samples of limonite iron ore, sinter, mixture for sinter and blast furnace slag were ground and separated by means of sieves into fractions of different grain size (200-125, 125-90, 90-63, 63-50 and < 50  m). Particular sample fractions in ratios 1:3, 1:1 and 3:1 were mixed, homogenised in a Spex type attachment for homogenisation and formed into briquettes under a pressure of 234 MPa for 1 min. All measurement were made on a diffractometric system and using a sequential semi-automatic Philips X-ray spectrometer. It was found that the results of measurements were influenced by grain size composition but also by grain distribution within briquette and by phase composition.

Samples in the form of metallic disc are grequently used in the analysis of cast iron by x-ray emission spectrometry and give good results for common analyses (determination of carbon, suplhur, phosphorus, silicon, manganese, copper, etc.) because of the uniform distribution of the analyte in the sample. However, the results of the analysis of metallic disc samples of cast iron to which cerium had bbeen added werw poor, wich could be attributed to a non-uniform distribution of compounds which cerium formed with sulphur and oxygen. A more detailed investigation of cerium distribution in relation to its content in the sample gave evidence of the presumed non-uniform distribution. Scanning electron microscopy confirmed the presence of unequally distributed aggregates of different size containing cerium, sulphur and oxygen. On the basis of an examination and comparison of published pretreatment procedures, a modified procedure including cerium precipitation with oxalate without transformation into the oxide form is proposed. Using this method, greater reliability of the results was obtained than in the analysis of cast iron samples without pretreatment, i.e. in the disc form.

In the laboratory for material structure investigation the X-ray emission spectrometry methods have been successfully applied for routine analysis of solid, powder and liquid materials. Non-aqueous solutions (organo-metallic phosphates), pickling products (nickel ore in sulphuric acid) and samples for pollution control (waste waters and soil) were analised qualitatively and semiquantitatively by x-ray spectrometric solution technique. The samples were directly measured in polypropylene liquidspecimen cell 3515 made by Spex and PW 1527/90 made by Philips, or as supported specimens on glass-fibre paper and cellulose. Measurements were made in a Philips x-ray spectrometer PW 1410/10 with chromium and rhodium target radiation. Vacuum, air and helium were used as radiation path media. Our experience in the application of the x-ray spectrometric solution technique shows that it is acceptable because it: - is non-destructive ; - enables direct measurement i.e. no sample preparation is necessary ; - requires small volumes of solution ; - is economical and fast. By adapting the existing x-ray spectrometer for analysis in helium path medium it is possible to measure light elements directly. This also anables a wide application of this technique for sample analysis in everyday practice.