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High-fluoride dentifrice can be used to manage dental erosion; however, little is known about it effect on root dentine previously demineralized. This study evaluated the effect of high-fluoride treatment on dentin de/remineralization exposed to an erosion challenge in vitro.Sound and demineralized dentine blocks were submitted to a 5-days-erosive challenge in soft drink (4/day during 90 s) and treated with fluoride solutions (0, 1,100, or 5,000 µg F/mL). After this, the percentage of surface hardness loss (%SHL) or recovery (%SHR) was calculated. Data were analyzed by one-way ANOVA and Tukey post hoc test with p fixed at 5%.High-fluoride treatment was able to reduce dentine remineralization and increase mineral recovery of previously demineralized dentine compared to other treatments tested (High-fluoride treatment was able to increase the remineralization and reduce the demineralization of root dentine submitted to an erosive challenge in vitro, being an option for the erosion prevention/treatment.

Comunicação apresentada no 4º Simpósio de Meteorologia e Geofísica da APMG – 6º Encontro Luso-Espanhol de Meteorologia, Sesimbra, 14-17 Fevereiro de 2005. Submitted by Paulo Fialho (paulofialho@uac.pt) on 2012-10-08T17:27:20Z No. of bitstreams: 1 2005APMG-191-194.pdf: 287856 bytes, checksum: fd8b1f0691bcd57c306804d575175b09 (MD5) Made available in DSpace on 2012-10-11T10:23:13Z (GMT). No. of bitstreams: 2 6295335750599558.zip: 283908 bytes, checksum: 559a5c75d61b03c0f273bfd44cdaf535 (MD5) 2005APMG-191-194.pdf: 287856 bytes, checksum: fd8b1f0691bcd57c306804d575175b09 (MD5) Previous issue date: 2005

Proceedings of the NATO Advanced Study Institute, held in Kolympari, Crete, Greece, from 15-24 May 1999. Copyright © 2000 Kluwer Academic Publishers. Understanding the physical and chemical properties of marine aerosol particles is crucial because of the role these particles play in a number of atmospheric processes. Marine aerosols affect climate directly through scattering and absorption of radiation and indirectly as they can act as cloud condensation nuclei and thus influence the albedo of clouds. In addition, marine aerosol particles play an important role in the cycling of various elements through the atmosphere. Many aspects about the origin of marine aerosols and their impact on atmospheric processes are still poorly known ar present and this lack of understanding stems in part from the relatively few measurements which have been performed in the most pristine areas of the earth. In order to improve our knowledge about the marine aerosol and its formation we established a land-based aerosol sampling station on the western coast of Terceira island (Azores). Here we present the first measurements of a project of sampling atmospheric particulate matter which started in Spring of 1999 and will be extended for one year.

Comunicação apresentada no 4º Simpósio de Meteorologia e Geofísica da APMG – 6º Encontro Luso-Espanhol de Meteorologia, Sesimbra, 14-17 Fevereiro de 2005. First results of aerosol optical depth measurements out with a Middleton SP02 sun photometer mounted on a sun tracker system (Kipp & Zonen 2AP) in Terceira Is. (Azores) are presented. SP01 and Cimel data from AERONET programme at Faial Is. are compared and analyzed with respect to weather conditions. These measurements are a part of the Portuguese Meteorological contribution for the development of a Global Station in the scope of the GAW/WMO programme in close cooperation with Azores University. The installation and operation of these instruments are partially funded by CLIMAAT (INTERREG IIIB – Project CLIMAAT – MAC 2.3/A3). Ground based measurements collected at Terceira Is. should be useful on long term referencing and assessing of the performance of space-borne instruments over North Atlantic Region.