RESUMO
We report the first ever measurements of the thermalization length of low-energy electrons injected into solid para-hydrogen at a temperature T ≈ 2.8 K. The use of the pulsed Townsend photoinjection technique has allowed us to investigate the behavior of quasi-free electrons rather than of massive, slow negative charges, as reported in all previous literature. We have found an average thermalization length ⟨z0⟩ = 26.1 nm, which is three to five times longer than that in liquid helium at the same temperature.
RESUMO
We report on the resonant Fabry Perot cavity of the PVLAS (Polarization of the Vacuum with LASer) experiment operating at λ = 1064 nm with a record decay time of 2.7 ms, a factor more than two larger than any previously reported optical resonator. This corresponds to a coherence length of 8.1 · 10(5) m. The cavity length is 3.303 m, and the resulting finesse is 770,000.
RESUMO
We describe recent improvements in the development of the high power laser system used in the motion induced radiation (MIR) experiment to amplify electromagnetic fields inside a microwave cavity. The improvements made on the oscillator stabilization, the pulse train shaping device, and the spatial beam uniformity are reported.
RESUMO
OBJECTIVES: Aim of the research was the demonstration of the efficacy of thermal water vs saline in the recurrent and chronic nasosinusal pathologies treatment. MATERIALS AND METHODS: 120 patients randomized into 2 groups of 60 subjects each, all affected by recurrent or chronic rhinosinusitis with/without I degree nasal polyposis. At the beginning and at the end of the study, in all the subjects the clinical history, objective examination and the instrumental analysis of nasal functions by active anterior rhinometry, acustic rhinometry, nasal mucociliary transport time determination and nasal mucosa scraping were performed. Patients of the study group underwent crenotherapy treatment (vapour inhalation, aerosol and nasal douching) with thermal water for 14 days at Salsomaggiore Thermal baths. Other patients underwent nasal douching and aerosol with saline twice a day for 14 days at the Rhinologic Centre of the ENT Clinic of Siena University. RESULTS: At the end of the study, only the patients undergone to crenothrapic treatment with salt-bromine-iodic water showed a significant improvement of nasal obstruction, rinorrea and number of nocturnal arousals. The improvement, even if present, was not significant in the control group. Same positive variations were observed concerning nasal mucosa congestion, nasal secretion and mucociliary transport time reaching the significance in the study group. CONCLUSIONS: Crenotherapy with salt-bromine-iodic water should be considered as efficacious therapeutic tool in the management of chronic and recurrent rhinosinusitis.