Plasma density profile reconstruction of a gas cell for Ionization Induced Laser Wakefield Acceleration

Laser-driven plasma wakefields can provide hundreds of MeV electron beam in mm-range distances potentially shrinking the dimension of the actual particle accelerators. The plasma density plays a fundamental role in the control and stability of the acceleration process, which is a key development for the future electron injector proposed by EuPRAXIA. A gas cell was designed by LPGP and LIDYL teams, with variable length and backing pressure, to confine the gas and tailor the gas density profile before the arrival of the laser. This cell was used during an experimental campaign with the multi TW-class laser at the Lund Laser Centre. Ionization assisted injection in a tailored density profile is used to tune the electron beam properties. During the experiment, we filled the gas cell with hydrogen mixed with different concentration of nitrogen. We also varied the backing pressure of the gas and the geometrical length of the gas cell. We used a transverse probe to acquire shadowgraphic images of the plasma and to measure the plasma electron density. Methods and results of the analysis with comparisons between shadowgraphic and interferometric images will be discussed

Early functional loading of conical Brånemark implants in the edentulous mandible : a 12-month follow-up clinical report

Treatment of patients with implant-supported mandibular fixed prostheses performed according to an early loading concept has shown excellent results in several reports. The outcome of such treatments with 4 implants, in which the posteriors are distally inclined, has not been reported. This clinical report describes a 12-month evaluation of 17 consecutive patients with 68 conical Branemark implants placed between the mental foramina according to a 1-stage surgical procedure. Fixed mandibular prostheses were connected to the implants an average of 33 days after implant placement. Clinical and radiographic examinations were performed at the time of placement of the fixed prosthesis and at a 12-month examination. Five implants were lost during the observation period, 3 before loading and 2 after prosthesis connection, rendering an implant survival rate of 93%. One patient lost her prosthesis because of a failing implant. The average marginal bone loss was 0.24 mm