[The determination of stomach contents left on the material objects and in the environment].

The objective of the present experimental study was to develop the qualitatively new method for the determination of stomach contents left on the material objects and in the environment with special reference to the cases of aspiration asphyxia. We proposed the original approach for the determination of the origin of the traces of stomach contents based on the detection of pepsin, an enzyme that digests in the acidic milieu protein substances, such as gelatin (hydrolyzed collagen), a component of the emulsion layer of X-ray and photographic films. Samples of the stomach contents were taken from a corpse and placed on the surface of various materials that did not absorb moisture or repulsed it. In addition, materials undergoing putrefactive decomposition were investigated. Moreover, stains left by the cadaveric lung sections from the subjects who allegedly died from aspiration asphyxia on the emulsion layers were studied. A specially developed method was employed to detect pepsin, the main enzyme of the gastric juice. The majority of the studied samples including the control ones exhibited pepsin activity. The results of the study suggest the possibility of application of the proposed method for the detection of stomach contents on the environmental objects provided the material being studied avoided putrefactive modification.

Present and future of the artificial heart driving system.

The totally artificial heart (TAH) is now in development in two trends. First, there is the development of a bridge system for temporary support of cardiac function. The TAH with the extracorporeal pneumatic driving system Sinus-IS is more efficient and safer. Parallel with this, a portable pneumatic driving system has been developed. That can be considered a stage in the development of the second trend: a totally implantable TAH. This article reviews problems of building of the Micron energy system to be used in implantable TAH designs.

[A pneumatic drive for the artificial heart apparatus with improved energy characteristics]. / Pnevmoprivod apparata "iskusstvennoe serdtse" s uluchshennymi énergeticheskimi kharakteristikami.

It has been shown in the present work that if gas compressibility is to be regarded as a reversible effect of energy accumulation, it can be used both for enhancing the pneumatic drive efficiency and maintenance of the goal-oriented self-control of the artificial heart apparatus on the whole. Such self-control provides an opportunity of realizing not only the pump functional characteristics of the apparatus, similar to the analogous parameters of the natural heart, but also of maintaining the reproduction of the other regulatory properties based on the interaction between the left and the right ventricles.

[A portable, movable pneumatic drive for an artificial heart with an autonomous electrochemical source of energy]. / Portativnyi perenosnoi pnevmaticheskii privod iskusstvennogo serdtsas avtonomym élektrokhimicheskim istochnikom énergii.

The authors have designed a pneumatic drive, which differs from the known ones in that it contains two electromagnetic two-linear and two-positioned air distributors while the motor operates in the mode excluding the change of its axis direction. This affords using a standard crank mechanism as a transformer of rotary motion to translational motion and reducing several times the power consumed. Besides, the two-linear and two-positioned air distributors allow a possibility of exercising a separate control over the time of the systole-diastole phases of the left and right ventricles. In this case both ventricles can work at 100% filling whereby maintaining the capacity of the artificial heart without additional energy consumption.

[Optimal mode of operation of an artificial heart]. / Optimal'nyi rezhim upravleniia iskusstvennym serdtsem.

Artificial heart operation was estimated from the view point of minimum energy consumption for the blood transport. The operation mode without breaks proved to be more economical in this respect, as compared to the mode with breaks during systole or diastole. A special control device has been designed just for the provision of uninterrupted artificial heart operation. This device improves the main functional characteristics of the artificial heart, increases the sensitivity to venous influx and provides invariance to the arterial pressure.

[Automatic control of an artificial heart with an autonomous energy source]. / Avtomaticheskoe upravlenie iskusstvennym serdtsem s avtonomnym istochnikom énergii.

Specific features and particularities in the design of the artificial heart control systems are considered, operated by various engines with a radioisotope energy source. The operation results showed the need in a complex approach to the problem solution. It should be based on optimized constructions, methods and principles of functioning for all ingradients of the artificial heart from the viewpoint of automatic control.