Role of twin boundaries on the vortex dynamics in YBa2_2Cu3_3O7_7

By means of a novel technique of rotating the applied current we have directly measured the influence of twin boundaries on the vortex motion in a YBa$_2$Cu$_3$O$_7$ single crystal. The results indicate that the effect of twin planes on the vortex dynamics starts to develop below a certain temperature, being responsible for an anisotropic viscosity in the vortex liquid state and a guided motion in the solid state.Comment: 4 pages, 4 figure

The superfluid vortex cooler

In this contribution a superfluid vortex cooler (SVC) is described. A SVC is a cooling device, the operation of which is based on the special properties of superfluid helium (He II). The SVC is small, simple, has no moving parts, and is gravity independent. It is capable of reaching temperatures as low as 0.65 K. First we have carried out a number of experiments, using a liquid-helium bath as a precooler for the SVC. Various geometries of the cooler components as well as the influence of the working pressure and the base temperature on the performance of the cooler have been investigated. Temperature below 1 K have been reached with a base temperature of 1.4 K. The next step has been combining the SVC with a pulse-tube refrigerator. In a preliminary experiment a lowest temperature of 1.19 K has been reached. Several ways to improve the system are suggested

Immediaat geplaatste fronttandimplantaten 2. Objectief en subjectief esthetisch behandelresultaat

In this study, the aesthetic outcome of treatment was analysed after immediate implant placement in 16 patients. During implant installation the gap between the implant and the buccal plate was filled with a bone substitute. Only single tooth replacements were included; the final crowns were placed 3-6 months after implant installation, all with individual manufactured abutments with an emerging profile and platform switching. Postoperative aesthetics were analysed based on clinical photographs and satisfactionquestionnaires. The objectively attained White Esthetic Score and Pink Esthetic Score with an average value of 8.4 and 11.8 respectively, scored high, as was also observed for patient’s satisfaction on both treatment and outcome (an average of 8.7). It may be concluded that flapless immediate implant placement together with the application of a bone substitute into the buccal gap in combination with a final crown with emerging profile results in objective and subjective good aesthetics and high patient satisfaction

Immediaat geplaatste fronttandimplantaten 2. Objectief en subjectief esthetisch behandelresultaat

In this study, the aesthetic outcome of treatment was analysed after immediate implant placement in 16 patients. During implant installation the gap between the implant and the buccal plate was filled with a bone substitute. Only single tooth replacements were included; the final crowns were placed 3-6 months after implant installation, all with individual manufactured abutments with an emerging profile and platform switching. Postoperative aesthetics were analysed based on clinical photographs and satisfactionquestionnaires. The objectively attained White Esthetic Score and Pink Esthetic Score with an average value of 8.4 and 11.8 respectively, scored high, as was also observed for patient’s satisfaction on both treatment and outcome (an average of 8.7). It may be concluded that flapless immediate implant placement together with the application of a bone substitute into the buccal gap in combination with a final crown with emerging profile results in objective and subjective good aesthetics and high patient satisfaction