934 resultados para chill storage
Resumo:
Seed storage under controlled environmental conditions represents one of the most important lines of research to be applied on short-lived forest species as Handroanthus. The present research aimed to identify the most suitable seed storage conditions and longevity behavior of Handroanthus umbellatus seeds subject to the following storage treatments: packaging permeable paper bags under a no-controlled laboratory temperature and humidity (control) and multiwall semipermeable bag at temperatures of -18 degrees C ,1 degrees C and 25 degrees C. Seeds were dried to 6.3% of water content. Stored seeds were evaluated every three months until 24 months for water content, germination percentage and vigor utilizing first counting test. Seeds of T. umbellata are orthodox, with low longevity under natural conditions, once they remain viable for less than 5 months. The best conditions of seed preservation of these species were obtained by storage at -18 degrees C in multiwall bags. Under these conditions physiological seed quality remains unchanged for a 24-month period.
Resumo:
The application of ultrasound waves with a conventional dental ultrasonic scaler on glass ionomer cements surface accelerated initial setting reaction and improved the mechanical properties. Objective: This study evaluated the ultimate tensile strength of glass ionomer cements after ultrasonic excitation and different water storage times. Material and method: Twelve specimens of each material (Fuji IX GP, Ketac Molar Easymix and Vitremer) were prepared, and six of each received a 30-second ultrasound application during initial setting of the cements. After storage of the 24 hours or 30 days, the specimens were sectioned into stick to microtensile testing and the mean ultimate tensile strength values were submitted to Welch’s ANOVA and Tamhane’s test. Result: The results showed that the Vitremer presented the highest mean tensile strength. The chemically set Fuji IX GP presented significantly higher mean tensile strength after 30 days than after 24 hours of storage (p < 0.05). At 24 hours, the ultrasonically set Fuji IX GP presented significantly higher mean tensile strength than their counterparts set under standard conditions (p < 0.05). Conclusion: Treatment with ultrasound increased the tensile strength of Fuji IX GP in the early period of maturation.
Resumo:
This study evaluated the efficiency of a toothbrush holder to prevent contamination of toothbrushes used by preschool children. For that, the sample was composed by children 6 years old, enrolled in an educational and recreational center in Araraquara/SP, and divided into 3 groups: G1: same continuing routine storage toothbrushes, G2: children received only a new toothbrush holder for storage; G3: they received new toothbrushes holder for storage and solution of chlorhexidine digluconate to 0.12% to dabble in the toothbrush after use. After brushing their teeth, toothbrushes were collected for microbiological analysis. The data were analyzed using the distribution of frequencies. It was observed that, in general, higher prevalence of the microorganism in the toothbrushes was Streptococcus viridans (58.97%), followed by Estafilococcus (35.90%), the bacillus of air (28.21%) and Neisseria mucosa (5.13%). Evaluating frequency, it was noted that the contamination presented by Streptococcus is higher in G1 when compared to G2 and G3, while for Estafilococcus, the presence was more significant in G3. Thus, it was concluded that the use of new toothbrushes holder able to avoid direct contact between brushes and allow drying without smothering could be an excellent alternative to educational institutions that require the storage group.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)