Deep levels,transport and THz emission properties of SiGe/Si quantum-well structures

Recharging of quantum confinement levels in SiGe quantum wells (QW) was studied by charge deep-level transient spectroscopy (Q-DLTS) for Si/SiGe/Si structures with different Ge contents in the SiGe layer. A peak with activation energy varying in the range from 0 to 100 meV in different tempera-ture intervals was observed in Q-DLTS spectra. Activation energies extracted from Q-DLTS measure-mens are in good agreement with energies of quantum confinement levels in the QW.     

Pathology of the lymphopharyngeal ring in children

The condition of tonsils was studied in 9612 children of organized establishments aged up to 14 years. Diseases of the tonsils were found in 34.8% cases (simple hyperplasia in 35.6%, chronic tonsillitis in 64.4% cases). In 63.3% cases chronic tonsillitis was accompanied by tonsillar hypertrophy. In 84% cases it proceeded with signs of tonsillogenous intoxication. Lymphopharyngeal ring pathology was more often than not found in 7-14 year old children (44.6%). The authors discuss problems of pathogenesis, clinical course, diagnostics and treatment of lymphopharyngeal ring pathology in children. They suppose that tonsillar pathology in children is to be considered as a systemic disease, the leading role in its pathogenesis seems to belong to the total lymphoid system of the organism. Proceeding from the fact that the tonsils in children are of great functional importance as they take part in the formation of local and general defensive immunologic reactions of the organism, the authors consider that in children it is necessary to give preference to conservative methods in the treatment of chronic tonsillitis.