Teste de raios x na avaliação da qualidade de sementes de abóbora

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Decomposição de argilas em forno de microondas e determinação simultânea dos seus constituintes principais por espectrometria de emissão óptica em plasma indutivamente acoplado

ANALYSIS OF CLAYS BY INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROMETRY AFTER CLOSED-VESSEL MICROWAVE-ASSISTED ACID DECOMPOSITION. In this work a closed-vessel microwave-assisted acid decomposition procedure for clays was developed. Aluminum, Ca, Fe, K, Mg, Na, Si, and Ti were determined in clay digestates by inductively coupled plasma optical emission spectrometry. The most critical parameter for total decomposition of clays was the composition of the reagent mixture. The applied power and the heating time exerted a less critical influence. Best decomposition conditions were attained using a reagent mixture containing 4 mL aqua regia plus 3 mL HF and the heating program was implemented in 12 min. The accuracy of the results was demonstrated using two standard reference materials and a paired t-test showed a good agreement between determined and certified values at a 95% confidence level.

Spikes em espectrometria alfa para analise de amostras geologicas

The technique of isotope dilution has been extensively utilized for determining the content of trace elements in geological samples; it has been especially useful for the determination of 238U and 234U contents in crustal materials with measurements made by alpha spectrometry. 232U-228Th has usually been used as diluent (spike) during the application of this analytical technique. More recently, 236U and 229Th have been used. Some methodological problems concerning the utilization of these spikes are presented with examples of experimental data obtained in analyses of groundwater and borehole spoil samples from Morro do Ferro, Pocos de Caldas (MG). -from English summary

Análise comparativa de métodos de avaliação da composição corporal em homens sadios e em pacientes com doença pulmonar obstrutiva crônica: antropometria, impedância bioelétrica e absortiometria de raios-X de dupla energia

The aim of this study was to examine the agreement between the results of body fat (BF and BF%), fat-free mass (FFM) and FFM index (FFMI= FFM/height2) as estimated by skinfold anthropometry (ANT), bioelectrical impedance (BIA) and dual-energy X-ray absorptiometry (DXA) in two groups of men (> or = 50 y), one comprising healthy individuals (n=23) and the other, patients with chronic obstructive pulmonary disease (COPD) (n=24). Comparisons between body composition techniques were done by repeated measures ANOVA; the Bland & Altman procedure was used to analyse agreement. RESULTS AND CONCLUSIONS: 1) comparison between healthy and COPD groups showed significant differences between all studied variables; 2) in the healthy group, values for BF, BF%, FFM and FFMI were not significantly different when BIA or ANT was compared to DXA; however, in COPD, values for BF and BF% were significantly higher and for FFM and FFMI significantly lower when BIA was compared to DXA; in contrast, no differences were shown between values for these variables when ANT was compared with DXA; 3) Bland & Altman test, in both groups, showed no agreement between BIA and DXA and between ANT and DXA; it was also shown that body fat was overestimated and fat free mass underestimated by BIA in relation to DXA.

Valor preditivo do potencial de implantação embrionário pela análise do perfil químico de meios de cultivo por espectrometria de massas (ESI-Q-ToF)

Objective: This case-control study analyzed mass spectrometry fingerprinting patterns of culture media samples used for embryo culture to predict embryo implantation. Methods: The culture medium harvested after embryo transfer of 22 embryos from 13 patients was used for the experiments. After embryo transfer, the remaining culture media were collected and samples were split in positive (n=8) and negative (n=14) implantation groups according to implantation outcomes (100% or 0% of implantation). Samples were individually diluted and injected directly to the Electrospray ionization (ESI) MS coupled to a Quadrupole Time-of-flight MS (Q-ToF-MS).Ions relative intensities of each spectrum were considered. Data analysis was conducted in MatLab 7.0 version using Partial Least Squares - Discriminant Analysis toolbox. Results: There were 3027 observed ions at 100% and 0% implantation groups by ESI-Q-ToF-MS. The statistical model could categorize the samples in two clusters, based on their positive and negative implantation outcomes. Less intense ions present in the mass spectra with statistical significance have contributed to the major differences to group distinction. Conclusions: Positive and negative implantation embryos showed a specific biochemical pattern present in culture media, which could be detected as a fast, simple and non-invasive way. This biochemical profile could help the selection of the most viable embryo, improving single embryo transfer and thus eliminating the risk and undesirable outcomes of multiple pregnancies. © Todos os direitos reservados a SBRA - Sociedade Brasileira de Reprodução Assistida.

Sistema para realização de medidas de luminescência com excitação por raios X

In this work is presented a versatile system for X-ray excited optical luminescence (XEOL) measurements. The apparatus was assembled from a sample holder connected to an optical fiber responsibly for the acquisition of the scintillation signal. The spectrum is registered with a CCD coupled in a spectrograph provided with diffraction gratings. The system performance was analyzed by exciting GdAlO3:Eu3+ 3.0 at.% with X-rays from a diffractometer and measuring the emission spectra. The system can be used to obtain precise and reliable spectroscopic properties of samples with various conformations without the loss of the required safety when dealing with ionizing radiations.

Análise de transitórios eletromagnéticos utilizando matrizes de transformação reais-sistemas trifásicos com a presença de cabos pára-raios

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Síntese e caracterização de partículas esféricas de poli(álcool vinílico) e poli(acetato vinílico) para utilização em embolização

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pesquisa e desenvovimento de novos materiais microporosos e mesoporosos para uso em ressonância magnética nuclear por imagem como agentes de contraste

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo teórico da relação entre número de CT de raios-X e Stopping Power de prótons

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Síntese de nanopartículas de sílica mesoporosa e aplicações como biomaterial

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo de propriedades anelásticas de MgB2

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Argilominerais: influência dos aditivos (cinza de bagaço de cana-de-acúcar e rocha sedimentar) no processo de sinterização

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Análise dos parâmetros clínicos periodontais e expressão genética de interferons alfa, gama e genes relacionados em indivíduos portadores de Síndrome de Down com doença periodontal

Pós-graduação em Ciências Odontológicas - FOAR

Hemograma, proteinograma e enzima gama-glutamil transferase de cães neonatos, do 3º ao 45º dia de vida, sob a ação da idade e da suplementação com luteína

Pós-graduação em Medicina Veterinária - FMVZ