Molecular dynamics simulation of the formation of Cu-Pt nanocontacts in the mechanically controlled break junction experiments.

The formation of the Cu-Pt nanocontacts has been investigated by means of classical molecular dynamics simulations. The simulations of the mechanically controlled break junction experiment have been performed in wide ranges of temperatures (0-300 K) and at relative Pt concentrations (0-20%). The structure of the breaking area has been studied 2 ns before the final breaking of the nanocontacts. The length of the breaking area increases with the increase of the temperature and decreases with the increase of the relative Pt concentration. The structure of the breaking area has been investigated by means of the radial distribution function method. The breaking area usually has one of the following structures: (i) a bulk-like structure, (ii) a structure consisting of centered icosahedrons rotated 90°, or (iii) an icosahedral structure composed of pentagonal rings. The structure of the breaking area is almost independent of the temperature and the stretching direction due to the strong Cu-Pt interaction.

[Prediction of the outcomes of renal replacement therapy for acute renal failure after cardiosurgical interventions].

The aim of the study was to evaluate the influence of different predictors on the outcomes of acute renal failure (ARF) in cardiosurgical patients. A hundred and five cases of ARF in January 1995 to August 2004 were retrospectively analyzed. Sixty-one patients received continuous renal replacement therapy (CRRT) and 44 patients had intermittent RRT (IRRT). Eighteen preoperative, perioperative, and postoperative risk factors were assessed. The overall hospital mortality was found to be 42%: 48.4% in the CRRT group and 33.3% in the IRRT group. A statistical analysis revealed 8 significant predictors of fatal outcomes: (1) the severity according to the APACHE II scale (25 +/- 1 scores); (2) the number of organ dysfunctions (3.6 +/- 0.2); (3) large-dose inotropic support; (4) artificial ventilation; (5) oliguria; (6) severe concomitant hepatic failure; (7) moderate-to-severe concomitant posthypoxic encephalopathy. CRRT improved survival in AFR associated with severe cardiorespiratory failure, oliguria, and cerebral dysfunctions. The paper discusses criteria for choosing the modes of renal replacement therapy.

[Effectiveness of plasmapheresis and its modifications in the treatment of cardiosurgical patients]. / Effektivnost' plazmafereza i ego modifikatsii v lechenii kardiokhirurgicheskikh bol'nykh.

The efficiency of plasmapheresis in the treatment of infectious complications and multiple organ dysfunctions was evaluated in 66 patients after heart surgery. Early plasmapheresis attenuated the cytokine-related systemic inflammatory response and organ damage. The optimal use of plasmapheresis modifications (membrane plasma filtration, plasma carboperfusion, cryoapheresis) improved the clinical outcomes.

[Tolerance of +Gz acceleration by pilots with tendencies to hypotensive reactions in hot climate conditions]. / Perenosimost' uskorenii +Gz letchikami so sklonnost'iu k gipotonicheskim reaktsiiam v usloviiakh zharkogo klimata

During acrobatic flying the acceleration tolerance of healthy and hypotensive pilots was studied under hot climate conditions. From the professional point of view pilots were very similar. The tolerance was determined on the basis of indirect indices derived from flight accelerograms (maximum and median acceleration values, number of peaks over 4 g. time of flying). The maximum value and the number of peaks of acceleration (+Gz) over 4 g can be recommended as practically indicative of the tolerance. The observations showed an adverse effect of initial hypotension occurring in hot climate on the acceleration tolerance. As compared with the controls, the tolerance decline in 12 hypotensive pilots was I.I. g and 0.6 g of the maximum and median values, respectively.