RESUMO
We have measured the full counting statistics of current fluctuations in a semiconductor quantum dot (QD) by real-time detection of single electron tunneling with a quantum point contact. This method gives direct access to the distribution function of current fluctuations. Suppression of the second moment (related to the shot noise) and the third moment (related to the asymmetry of the distribution) in a tunable semiconductor QD is demonstrated experimentally. With this method we demonstrate the ability to measure very low current and noise levels.
RESUMO
A 62-year-old man, under long-term corticosteroid therapy for pigeon breeder's disease, was admitted to endocrinology disease department for cutaneous abscess on back, limbs and scalp. Culture of various bacteriological samples (cutaneous abscess, blood culture) isolated Nocardia otitidiscaviarum. The patient was treated by trimethoprime-sulfametoxazole during several weeks with abscess disappearance. Our laboratory quickly identificatied a bacteria belonging to the Nocardia genus, with simple technique, later confirmed by a specialized laboratory (Pr. Boiron Claude Bernard University Lyon I) with identification of Nocardia otitidiscaviarum. The proof of pulmonary nocardiosis could not be established despite the existente of several risk factors. Prognosis is poor for immunocompromised patients, but the secondary cutaneous dissemination phase presented a favourable evolution under antibiotic therapy.