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URI permanente desta comunidadehttps://repositorioacademico.universidadebrasil.edu.br/handle/123456789/30
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Resultados da Pesquisa
Item Tolerância à radiação UV-B do fungo entomopatogênico Metarhizium Rileyi para o desenvolvimento com o agente microbiano para o manejo das principais espécies lepidópteras nas culturas de soja e algodão(Universidade Brasil, 2022) Andrade, Eliezer Pereira de; Rangel, Drauzio Eduardo NarettoSoybean, corn and cotton crops are afflicted by several noctuid pests, therefore, the development of bioinsecticides can provide the control of these pests with the sustainability of the system. The fungus Metarhizium rileyi has the greatest potential since its epizootics decimate caterpillar populations in the absence of fungicide applications. The low survival of insect-pathogenic fungi when used for insect control in agriculture, however, is mainly due to the deleterious effects of ultraviolet radiation and heat from solar irradiation. In this study, fourteen isolates of M. rileyi were studied and compared with isolates ARSEF 324 and ARSEF 2575 of Metarhizium acridum and Metarhizium robertsii respectively, which sensitivity to UV-B radiation had been previously studied. Conidial suspensions were exposed at room temperature (ca. 26 °C) to 847.90 mWm2 of Quaite-weighted UV-B using two fluorescent lamps TL 20W12 RS (Philips, Eindhoven, Holland). The plates containing the conidial suspensions were irradiated for 1, 2, and 3 h, providing doses of 3.05, 6.10, 9.16, and 12.21 kJ m2 , respectively. Remarkable variability in conidial UV-B tolerance was found among 14 isolates of M. rileyi. Isolate CNPSo-Mr 150 was the most tolerant isolate (germination above 80% after 2 h exposure), which was comparable to ARSEF 324 (germination above 90% after 2 h exposure), the most tolerant Metarhizium isolate. The least tolerant isolate was CNPSo-Mr 597 (germination below 5% after 2 h exposure). Nine isolates were similar with ARSEF 2575 (germination above 50% after 2 h exposure). Concluding, the majority of M. rileyi isolates can endure 1 or 2 h of UV B radiation exposure. However, after 3 h exposure caused great reduction of germination below 40% for all isolates, except for CNPSo-Mr 150 and ARSEF 324.Item Avaliação dos efeitos da desinfecção química e com radiação ultravioleta na estabilidade dimensional de diferentes materiais de moldagem odontológicos(Universidade Brasil, 2021) Santos Neto, Antonio Vinicios dos; Navarro, Ricardo ScarparoThe disinfection of molds obtained with dental impression materials is within the biosafety protocols, in the control of cross-infection of microorganisms in dental offices, prosthesis laboratories, professionals and patients, being currently the target of greater attention due to the pandemic of COVID-19, with the implementation of alternative disinfection protocols and methods. The purpose of this study was to compare the effects of disinfection by ultraviolet radiation and chemical disinfection on dimensional stability of different dental molding materials. Acrylic resin mannequin molds with irreversible hydrocolloidal materials (alginate) (n = 25) and elastomer (condensation silicone) (n = 25) were used with different disinfection methods (n = 5): G1- negative control: no treatment, G2- Glutaraldehyde 2% (10 min), G3- Sodium hypochlorite 1% (10 min), G4- UV-C radiation (λ = 254 nm) (30 s), G5- Autoclave (positive control) (15 min). The molds after the treatments were cast with special plaster. After 24 h, the plaster models were measured by a calibrated, blinded researcher, with a caliper in determined places on the upper first molar: mesio-distal (MD-O) and vestibulo-lingual (VL-O) and buccal cervical-occlusal face (CV-B) and mesio-distal (MD-V). The data were tabulated and analyzed using the statistical tests of Kolmogorov-Smirnov, ANOVA one-way and Tukey tests (p <0.05). There were no statistically significant differences in the linear values of plaster models between chemical (Glutaraldehyde 2%, sodium hypochlorite 1%) and physical (UV-C radiation) disinfection methods with the control (p> 0.05), the autoclave showed a significant difference in relation to the control and the different methods of disinfection (p <0.05) with greater dimensional change for both impression materials. It can be concluded that the methods of chemical disinfection (Glutaraldehyde 2%, Sodium hypochlorite 1%) and physical (UV-C radiation) maintained the dimensional stability of the dental impression materials alginate and elastomer (condensation silicone).