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Biomedical subjects

V E Zakharov

Publications and source records attributed to V E Zakharov.

14 recordsLinked to original sources
PubMed2004

Weak turbulent Kolmogorov spectrum for surface gravity waves.

We study the long-time evolution of surface gravity waves on deep water excited by a stochastic external force concentrated in moderately small wave numbers. We numerically implemented the primitive Euler equations for the potential flow of an ideal fluid with free surface written in Hamiltonian canonical variables, using the expansion of the Hamiltonian in powers of nonlinearity of terms up to fourth order. We show that because of nonlinear interaction processes a stationary Fourier spectrum of a surface elevation close to <|eta(k)|(2)> approximately k(-7/2) is formed. The observed spectrum can be interpreted as a weak-turbulent Kolmogorov spectrum for a direct cascade of energy.

Journal Article↗
PubMed2002

Freely decaying weak turbulence for sea surface gravity waves.

We study the long-time evolution of deep-water ocean surface waves in order to better understand the behavior of the nonlinear interaction processes that need to be accurately predicted in numerical models of wind-generated ocean surface waves. Of particular interest are those nonlinear interactions which are predicted by weak turbulence theory to result in a wave energy spectrum of the form of [k](-2.5). We numerically implement the primitive Euler equations for surface waves and demonstrate agreement between weak turbulence theory and the numerical results.

Journal Article↗
PubMed1992

[Combined action of doxycycline and mytilan on the immune response to tularemia antigen].

Combined action of doxycycline and mytilan, a natural polysaccharide, on the primary immune response to the antigen of the tularemia vaccinal strain in CBA mice was studied. The polysaccharide was used to compensate the immunosuppressive effect of doxycycline high doses on the humoral immune response. The maximum stimulation of the antibody titers as compared to the controls (more than 250 per cent) was observed when mytilan was administered simultaneously with or prophylactically 3 days prior to the antibiotic in doses of 2.5 and 25 mg/kg. The use of mytilan in combination with doxycycline high doses made it possible to compensate the antibiotic-induced decrease of DTH and even to stimulate it as compared to the controls. The highest levels of DTH (150 per cent against the control) were observed when mytilan was administered prophylactically in doses of 2.5 and 11.25 mg/kg 3 days prior to immunization. Mytilan had the highest stimulating effect on antibody production. The combined use of doxycycline and mytilan was characterized by significant stimulation of antibody production and DTH when the dose/time regimens were rational.

Animals↗
PubMed1991

[Surgical tactics in occlusive lesions of the brachiocephalic and coronary arteries].

Surgical management of combined arterial occlusions is a difficult problem. Combined lesions of the coronary arteries and brachiocephalic trunk are marked by significant mutual aggravation. The authors examined 48 patients with this pathological condition in the last 4 years, 32 of them underwent restorative surgical interventions. The direct effect was positive in 87% of patients. Four patients died after the operation. Comparative evaluation of the late-term results was carried out by the actuarial method. The authors believe a stage-by-stage character of the intervention to be expedient, except for cases of one-stage critical ischemia carried out simultaneously in two arterial channels and the possibility of simultaneous reconstruction of the sternotomy approach.

Arterial Occlusive Diseases↗
PubMed1990

[Simultaneous intrathoracic restoration of the coronary and brachiocephalic blood flow].

The treatment of 3 patients with combined occlusive affection of the brachiocephalic and coronary arteries is discussed. A one-stage intrathoracic operation was carried out. Prosthetics of one or two brachiocephalic branches was conducted at first after which a double of triple aortocoronary shunt was formed under conditions of extracorporeal circulation with the use of cardioplegia. The outcome of treatment was favourable. The formation of an aortobifemoral shunt will be undertaken in one of the patients in a short time. Various problems of tactical and surgical character in one-stage correction of the coronary and brachiocephalic blood flow are discussed.

Arteriosclerosis↗