Noise model application to small hydroelectrical power plants impact evaluation in the Aosta Valley territory.

In this paper measurements, results and model estimates, with reference to hydroelectric power plant noise emissions in the Aosta Valley territory, are compared in different contexts. The analysis was performed to evaluate and point out the influence of the noise source context on the accuracy of the model results. The estimates were implemented considering power plants as: point sources and area sources taking (or not) into account the building elements of the plant. This method allowed evaluating the detail that is suitable to achieve in an estimate and to justify possible simplifications in this kind of noise source description. Noise measurements were carried out simultaneously, at different distances from the power plants that were taken into account. The measurement results at the closest points to the sources were used as the model input data, while the levels found at the other points were used for comparison with the estimate results.

[Resin and glass-ionomer sealants. Indications, mechanism of action, and application technics]. / I sigillanti in resina ed al cemento vetro-ionomerico. Indicazioni, meccanismo d'azione e tecniche di applicazione.

The usefulness and indications to treatment with sealants in pedodontics are examined. Sealants are classified and the action mechanism of sealant resins and the application techniques needed for correct positioning of the material are described. The use of the new glass-ionomer cement sealants, with their advantages and disadvantages, are then discussed and the preventive and economic value of occlusive seals evaluated.

[Finishing and polishing of an anterior hybrid composite--Herculite XR. SEM evaluation]. / Rifinitura e lucidatura di un composito ibrido per anteriori--HERCULITE XR. Valutazioni al SEM.

A study was a conducted in order to discover finishing and polishing effectiveness, by particular operative method, on HERCULITE XR, sub-micron hybrid composite. The study was realized on 35 incisors extracted for periodontal reasons, treated with "labial veneers" according to Jordan (1987), divided into 7 groups each containing 5, and finished with different technique. After treatment, the teeth were subjected to SEM examination. The results showed that the high speed finishing technique by twelve and thirty fluted carbide burs and final polishing with Command Ultrafine Luster Paste produces the smoothest and flatest surface of HERCULITE XR. Furthermore the HERCULITE XR/enamel margin doesn't appear fractured or disrupted. Since finishing and polishing rotary techniques in accordance with the characteristic of each type of composite resins.

[Autotransplantation of tooth germs]. / Considerazioni sull'autotrapianto dei germi dentari.

The authors explained, after an attentive review of literature, the clinic and therapeutic procedures about dental germs' transplant. They show the indications for this surgical operation, the procedure for selection of grafting germs and the current surgical technique to do it.