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M Alexe

Publications and source records attributed to M Alexe.

3 recordsLinked to original sources
PubMed2005

Chaos supported stochastic resonance in a metal-ferroelectric-semiconductor heterostructure.

An experimental study is presented on a complex nonlinear system showing a particular type of dynamics that can be interpreted as stochastic resonance. The system consists of a metal-ferroelectric-semiconductor structure, which plays the role of a nonlinear element in an electric circuit with linear resistance, inductance, and capacitance connected in series (RLC series circuit) driven externally by a high-amplitude harmonic voltage source. The system presents various kinds of nonlinear behavior, of which the simplest, consisting of a period-doubling evolution to chaos, is of interest to this study. The broadband intrinsic chaos emerging after a period-doubling sequence exists for a large range of frequencies of the driving voltage. The appearance of the chaotic dynamics is associated with the promotion of a low-frequency harmonic spectral component. This is interpreted as stochastic resonance with intrinsic chaos replacing noise, the usual variable in regular SR.

Journal Article↗
PubMedDate not supplied

[The indications of bronchial resection and anastomosis in lung cancer].

Bronchial resection and anastomosis represents an alternative to the pneumonectomy in patients with severe impairment of pulmonary function and/or other diseases which make such radical surgery too risky. The authors present two clinical cases of right upper lobe lung cancer (a squamous-cell carcinoma and an adenocarcinoma) admitted in the Thoracic Surgery Department of the National Institute of Pulmonology "Marius Nasta" from Jan-March 2001, in which they could not perform pneumonectomy because of unacceptable high risks. In both patients a right upper lobectomy with "sleeve" resection was done, with the anastomosis of right main bronchus to the intermediary one. The clinical, bronchoscopic and functional results were excellent. The literature review also shows very good results of this technique in the surgical treatment of lung cancer. For these reasons, the authors recommend this procedure in all the cases in which it can be technically applied; more than that, the survival rate is similar with other more radical techniques, but without any complications.

Adenocarcinoma↗