INTRODUÇÃO: Os cimentos de ionômero de vidro (CIVs) liberam elementos inorgânicos e monômeros orgânicos residuais que têm o potencial de causar efeitos deletérios sobre as células pulpares. OBJETIVO: Identificar e quantificar os elementos inorgânicos presentes em diferentes CIVs, bem como os componentes liberados por estes materiais em meio de cultura celular. MATERIAL E MÉTODO: Espécimes cilindricos de dois CIVs modificados por resina para base/forramento (Vitrebond e Fuji Lining LC), dois CIVs modificados por resina restauradores (Vitremer e Fuji II LC) e dois CIVs convencionais restauradores (Ketac Fil Plus e Ketac Molar Easymix) foram preparados e analisados por Espectrometria de Fluorescência de Raios X por Energia Dispersiva (EDXRF). Em seguida, extratos de 24h desses materiais foram obtidos e analisados por EDXRF e por Cromatografia Gasosa/Espectrometria de Massa (CG/EM). RESULTADO: Os elementos inorgânicos identificados em maior porcentagem nos CIVs Vitrebond, Fuji Lining LC, Vitremer, Fuji II LC e Ketac Fil Plus foram estrôncio, silício e alumínio, enquanto o zinco foi detectado apenas no Vitrebond. O Ketac Molar Easymix apresentou maior porcentagem dos elementos lantânio, cálcio, alumínio e silício. Estrôncio foi detectado nos extratos de todos os materiais, exceto no Ketac Molar Easymix; cálcio estava presente no extrato do Ketac Fil Plus; zinco apenas no Vitrebond; e silício no extrato do Fuji II LC . O HEMA foi identificado nos extratos de todos os CIVs modificados por resina, e o iodobenzeno, somente no Vitrebond. CONCLUSÃO: Entre os CIVs estudados, o Vitrebond é o que libera mais componentes com potencial citotóxico.

INTRODUCTION: Glass ionomer cements (GICs) release inorganic elements and organic residual monomers with the potential for deleterious effects on pulp cells. OBJECTIVE: To identify and quantify inorganic elements present in different GICs and released components from these materials in cell culture medium. MATERIAL AND METHOD: Samples of two resin-modified GICs for base/liner (Vitrebond and Fuji Lining LC), two resin-modified restorative GICs (Vitremer and Fuji II LC) and two conventional restorative GICs (Ketac Fil Plus and Ketac Molar Easymix) were prepared and analyzed by Energy-Dispersive X-Ray Fluorescence Spectrometry (EDXRF). Extracts of these materials were obtained by immersion of each sample in separate containers of DMEM for 24 h (total surface-liquid ratio = 45.7 mm²/mL). The extracts were analyzed by EDXRF and Gas Chromatography-Mass Spectrometry (GC-MS). RESULT: Higher percentages of strontium, silicon and aluminum were identified in Vitrebond, Vitremer, Fuji Lining LC, Fuji II LC, and Ketac Fil Plus, while zinc was detected only in Vitrebond. Ketac Molar Easymix presented a greater atomic composition of lanthanum, calcium, aluminum and silicon. Strontium was detected in the extracts from all materials except Ketac Molar Easymix; calcium was present in extracts from Ketac Fil Plus; zinc only in Vitrebond; and silicon in Fuji II LC extract. The analysis by GC-MS detected 2-hydroxyethyl-methacrylate (HEMA) in the extracts from all resin-modified GICs, and iodine benzene was detected only in the Vitrebond extract. CONCLUSION: Of the GICs sampled, Vitrebond released the highest number of components with cytotoxic potential.

Este trabalho descreve a preparação de biodiesel proveniente de óleo de babaçu, mamona e misturas destes em várias proporções, utilizando compostos alcalinos de estrôncio (SrO + SrCO3 + Sr(OH)2) como catalisadores heterogêneos. A mistura de óleos dessas oleaginosas foi utilizada na produção de biodiesel com parâmetros de qualidade que atendam a legislação vigente. O catalisador foi caracterizado por difratometria de raios X (XRD), fisissorção de gas (método BET), microscopia eletrônica de varredura (SEM), espectroscopia de raios X por dispersão em energia (EDX) e espectroscopia no infravermelho com transformada de Fourier (FTIR). Os parâmetros reacionais foram acompanhados através da viscosidade dos biodieseis obtidos. As reações de transesterificação usando os compostos de estrôncio apresentaram taxas de conversões de 97,2% (óleo de babaçu), 96,4% (óleo de mamona) e 95,3% (mistura de óleo de babaçu com óleo manona na proporção de 4:1).

This work describes the preparation of babassu, castor oil biodiesel and mixtures in various proportions of these oils, using alkaline compounds of strontium (SrCO3 + SrO + Sr (OH)2) as heterogeneous catalysts. The mixture of oils of these oleaginous sources was used in the production of biodiesel with quality parameters that meet current legislation. The catalyst was characterized by X-ray diffractometry (XDR), physisorption of gas (BET method), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR). The viscometric technique was used to monitor the optimization. The transesterification reactions performed using strontium compounds reached conversion rates of 97.2% babassu biodiesel (BB), 96.4% castor oil biodiesel (COB) and 95.3% Babassu/Castor Oil Biodiesel 4:1 (BBCO41).

Cytotoxic activity of eight plant extracts, native from the Mid-West of Brazil comprising Cerrado, Pantanal and semideciduous forest, was evaluated for MDA-MB-435, SF-295, and HCT-8 cancer cell strains. A single 100 µg.mL-1 dose of each extract was employed with 72 h of incubation for all tests. Doxorubicin (1 µg.mL-1) was used as the positive control and the MTT method was used to detect the activity. Cytotoxicity of distinct polarities was observed in thirty extracts (46%), from different parts of the following species: Tabebuia heptaphylla (Vell.) Toledo, Bignoniaceae, Tapirira guianensis Aubl., Anacardiaceae, Myracrodruon urundeuva Allemão, Anacardiaceae, Schinus terebinthifolius Raddi, Anacardiaceae, Gomphrena elegans Mart., Amaranthaceae, Attalea phalerata Mart. ex Spreng., Arecaceae, Eugenia uniflora L., Myrtaceae, and Annona dioica A. St.-Hil., Annonaceae. Extracts of at least two tested cell strains were considered to be highly active since their inhibition rate was over 75%.

Since the introduction of GC there has been an ongoing interest in reducing time of analysis resulting in new terms and definitions such as ultra fast gas chromatography (UF-GC). One of the most used definitions describes UF-GC as a technique that combines the employment of short narrow bore column with very fast temperature programming rates producing chromatographic peaks in the range of 50 ms and allowing separations times in 1-2 min or less. This paper summarizes the analytical approaches, the main parameters involved and the instrumentation towards UF-GC.

Automotive gasoline consists of a complex mixture of flammable and volatile hydrocarbons derived from crude oil with carbon numbers within the range of 4-12 and boiling points range of 30-225 ºC. Its composition varies with the kind of crude oil and the type of refinery process that they undergone. Aromatics hydrocarbons, in particular benzene, toluene, ethylbenzene and isomeric xylenes (BTEX) are the toxic group constituents presents. GC-FID was employed to quantify these hydrocarbons in 50 commercial gasoline samples from Piauí state. Statistical analysis techniques, such as PCA and HCA were used to analyze the data. Moreover, several validation parameters were evaluated.

In this work we have investigated the properties of CdTe thin films grown on glass substrates by Hot Wall Epitaxy. Its most important feature is the growth at very low temperatures, which would allow the growth even on polymer substrates. Our samples were grown at temperatures between 150 and 250 ºC at a growth rate between 0.2 and 2 µm/h. The CdTe films were characterized by x-ray diffraction, scanning electron microscopy and optical transmission. The x-ray teta-2teta scans revealed films with cubic structure and a very high degree of preferential orientation. In fact, for films thicker than 1 µm, no other reflections have been observed on the spectra besides the (111), (333) and (444). The scanning electron micrographs showed a grain size about 0.3 µm and the optical transmission indicated a very good optical quality of the interfaces, showing pronounced interference fringes.

Com o objetivo de avaliar a dispersão de Aedes aegypti e Ae. albopictus para a área rural, foram instalados pneus em quatro transectos (Norte, Sul, Leste e Oeste), a cada 5 Km, do limite da zona urbana de Londrina em direção a zona rural. Larvas de Culicidae foram coletadas quinzenalmente de agosto de 1998 a agosto de 1999. Um total de 62.517 larvas de Culicidae foram coletadas, distribuídas entre as seguintes espécies: Aedes albopictus (21.71%); Ae. aegypti (5.54%); Ae. terrens (0.53%); Ae. fluviatilis (0.36%); Anopheles argyritarsi (0.01%); Culex quinquefasciatus (48.37%); Cx. mollis (8.88%); Cx. eduardoi (8.65%); Cx. corniger (0.61%); Cx. bigoti (0.24%); Cx. grupo coronator (0.12%); Limatus durhanii (4.61%) e Toxorhynchites sp. (0.32%). Houve uma drástica diminuição na população de Ae. aegypti dos limites da cidade para a zona rural (x1= 21.72 ± 4.71; x2=0.00) e um aumento da população de Ae. albopictus (x1 = 15.64 ± 2.73; x2 = 38.37 ± 8.87). Aedes aegypti não foi encontrado somente nos pontos situados a 30 Km da cidade; no entanto, Ae. albopictus foi encontrado em todos os pontos. Conclui-se que ambas espécies encontram-se dispersas para a zona rural da área estudada e que é necessário um redimensionamento da área de controle destes vetores, já que a zona rural pode servir como um refúgio destas espécies.

Seventy-two tyres were placed in four transects (Northern, Southern, Eastern and Western), every 5 km, from the Londrina city limits to the rural areas, to verify the dispersion of Aedes aegypti and Ae. albopictus vectors. Mosquito larvae were collected fortnightly from August 1998 to August 1999. Data were organized according to the average number of larvae collected for each species in each collection site. A total of 62,517 mosquito larvae were collected and distributed into the following species: Aedes albopictus (21.71%); Ae. aegypti (5.54%); Ae. terrens (0.53%); Ae. fluviatilis (0.36%); Anopheles argyritarsi (0.01%); Culex quinquefasciatus (48.37%); Cx. mollis (8.88%); Cx. eduardoi (8.65%); Cx. corniger (0.61%); Cx. bigoti (0.24%); Cx. grupo coronator (0.12%); Limatus durhanii (4.61%) e Toxorhynchites sp. (0.32%). There was a drastic decrease in the Ae. aegypti population from the city limits to the rural area (x1= 21.72 ± 4.71; x2=0.00) and an increase in the population of Ae. albopictus (x1 = 15.64 ± 2.73; x2 = 38.37 ± 8.87). Aedes aegypti was not present in the collection sites located 30 km away from the urban area; however, Ae. albopictus was found in all the sites. Although the frequency rate for the Aedes aegypti was low, both species were dispersed in the rural area studied. The redimensioning of these vectors’ control areas is recommended since rural areas can function as reservoirs for these species.