Cotunneling current through a two-level quantum dot coupled to magnetic leads: the role of exchange interaction.

The cotunneling current through a two-level quantum dot weakly coupled to ferromagnetic leads is studied in the Coulomb blockade regime. The cotunneling current is calculated analytically under simple but realistic assumptions as follows: (i) the quantum dot is described by the universal Hamiltonian, (ii) it is doubly occupied, and (iii) it displays a fast spin relaxation. We find that the dependence of the differential conductance on the bias voltage is significantly affected by the exchange interaction on the quantum dot.

[The health status of the rural population living in the areas contiguous with industrial towns].

Exposed to environmental pollution with emissions from industrial enterprises, the population of their contiguous rural areas faces a high risk of their health. The studies of the health status of the population from the contiguous rural areas versus that from the non-contiguous ones have established that measurements of a risk to the children's health revealed the highest risk among the contiguous areas in the Sterlitamaksky district and the least risk among the non-contiguous ones in the Askinsky district. The markers of carcinogenic ill-being in the contiguous rural areas were the incidence of cancer of the lip, esophagus, stomach, larynx, cervix uteri, uterine appendages, and prostate and leukemia.

[Hygienic significance of noise level in the development of diseases with temporary disability among petroleum-processing plant workers].

A correlation was established between morbidity with temporary disability among oil-processing plant workers and the levels of the noise dosages received in one working shift. The morbidity rate among the engine-drivers examined was generally higher than that in the group of operators. The correlational analysis of morbidity versus the complex hazard indices revealed that the latters' growth resulted into increasing morbidity rate, but the same correlation was less vivid in case with the workers affected with the smallest noise dosages (up to 1.