The experimental model of laboratory animals’ intoxication by polyacrylonitrile pyrolysis products

Purpose of research – To develop an experimental model of intoxication of laboratory animals by polyacrylonitrile pyrolysis products. Materials and methods. The study was performed on the rats. Pyrolysis of polyacrylonitrile fibers was carried out at temperature of 270–350 °C. The laboratory animals were exposed to static inhalation intoxication by pyrolysis products for 15 min. Vital signs were determined in animals before and 5 minutes after intoxication. Arterial blood oxygenation index and acid-base state parameters were evaluated at 10 min after exposure. Qualitative detection of cyanides in brain and myocardial samples obtained 15 minutes after intoxication was carried out by gas chromatography. Results and discussion. It was found that the weight of the material (containing 85 % polyacrylonitrile), which pyrolysis products lead to the death of 50 % of laboratory animals within 24 hours after exposure, was 0.81 ± 0.15 g. The animals showed signs of poisoning by substances interrupting the processes of cell bioenergy when exposed to pyrolysis products obtained under specified conditions. The evident bradycardia and bradypnea (p < 0,05), and significant decrease in rectal temperature was marked. The exposed animals did not differ (p > 0,05) from the rats of the control group by the parameters of oxygenation. The signs of decompensated metabolic acidosis were detected in blood. The cyanide peak was detected by gas chromatography with a retention time of 3.78 min in brain and heart muscle biopsies. The experimental model, in which inhalation exposure of pyrolysis products of polyacrylonitrile fibers led to severe intoxication of laboratory animals, was developed. The model can be used to search for means of etiotropic and pathogenetic therapy of poisoning by combustion products of nitrogen-containing polymeric materials

Creation of a Permanently Operating GNSS Reference Station in the City of Alapaevsk

The stages of creation are given, the procedure and methodology for the installation and determination of the coordinates of the permanent GNSS base station in the city of Alapaevsk are presented. Reports were prepared on post-processing and equalization of the coordinates of the base station relative to the GGS points using the specialized software “Topcon Tools”, the coordinates of the base station. Equalization of the base station from the reference geodetic network is carried out, the accuracy of coordinates is estimated, and the base station is linked to it. Conclusions are made about the health of the base station.Приведены этапы создания, представлены порядок и методика работ по установке и определению координат постоянно действующей базовой станции ГНСС в г. Алапаевске. Составлены отчеты по постобработке и уравниванию координат базовой станции относительно пунктов ГГС при помощи специализированного программного обеспечения «Topcon Tools». Выполнено уравнивание базовой станции от опорной геодезической сети, даются оценка точности координат, привязка к ней базовой станции. Сделаны выводы о работоспособности базовой станции

СЕПСИС, ВЫЗВАННЫЙ HAEMOPHILUS INFLUENZA

The article provides clinical examples of hemophilic sepsis developed in non-vaccinated children with immunodeficiency conditions resulted in death.В статье приводятся два случая гемофильного сепсиса, развившегося у невакцинированных детей с иммунодефицитными состояниями, закончившиеся летальным исходом