Atmospheric pressure fluctuations in the far infrasound range and emergency transport events coded as circulatory system diseases

[Influence of present weather conditions on the appeal of Bishkek and Osh residents for emergency care because of cardiovascular diseases]

Purpose of the study. To determine the influence of air temperature, atmospheric pressure, precipitation, fast weather changes on the number of emergency calls to patients with heart disease in the cities of Bishkek and Osh.

MATERIALS AND METHODS

The data of calls to the ambulance station of the cities of Bishkek and Osh for a 20-year period (1998-2018) were analyzed by classes of diseases in accordance with the ICD 10^th revision: A00-R99 - from all causes; I00-I99 - diseases of the circulatory system. More than 450 thousand ambulance calls were analyzed. To assess the meteorological indicators, the archived data of the site https://www.gismeteo.ru/diary/5327 were used. Correlation analysis was performed using the SPSS program.

Results and conclusion. The data obtained indicate the presence of moderate and strong statistically significant relationships in the number of patients with cardiovascular diseases seeking medical care with periods of prolonged heat, days with a fast weather change, days with increased atmospheric pressure after the invasion of the cold air front and precipitation. The necessity of seasonal prophylaxis of meteopathic reactions taking into account weather changes is shown.

Ultradian Biorhythms of C57BL/6 Mice Body Temperature under Constant Illumination or during Natural Day-Night Cycle

The study analyzed the dynamics of intraperitoneal body temperature in C57BL/6 mice during 39 days of uninterrupted measurements. When mice were exposed to constant illumination, the ultradian oscillations of body temperature demonstrated the rhythms with periods of 2 h, 60 min, and 12 min, which were the higher harmonics of the circadian temperature oscillations. In two mutually isolated groups exposed to constant illumination, the phases of revealed biorhythms coincided. When the mice maintained under natural illumination, the body temperature demonstrated the ultradian rhythms with the same periods, which indicated that constant illumination did not distort the parameters of ultradian biorhythms. Probably, there is an external biotropic factor with similar harmonic spectrum, which synchronizes these biorhythms.

Past, present and future of the climate and human health commission

The following paper presents the history of the Climate and Human Health Commission at the International Society of Biometeorology after more than one decade since its creation. A brief history of the origins of the human biometeorology is revealed through some of the main research topics and publications of the founders of the society in this field. Secondly, it is presented as a brief review of the activities of the commission in the last 10 years, based on the reports that have periodically been submitted by members of the commission to the Bulletin of the society. A summary of the topics of interest on human biometeorology and the most frequent research topics are also described. Thirdly, the need of adapting human biometeorology contents, methods and techniques to a changing world is articulated according to some of the new environmental threats in the XXI century. Finally, a list of future actions and research lines collected through a form from members of the commission is presented. The paper concludes with the existence of great challenge for human biometeorology in order to transform biometeorological knowledge into specific services to improve the wellbeing of human beings.

Tympanic membrane pressure buffering function at quasi-static and low-frequency pressure variations

Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%-70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa-0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.

The Effects of Atmospheric Pressure Fluctuations on Human Behaviour Related to Injury Occurrences: Study on the Background of Low and Moderate Levels of Geomagnetic Activity

The effects of slight atmospheric pressure fluctuations (APFs) within two ranges of periods attributed mostly to far infrasound (3 s–120 s) and internal gravity waves (120 s–1200 s) on human behaviour related to injury occurrences, within the one-year interval, are examined. Special interest is paid to the analysis of combined effects of APFs and geomagnetic activity (GMA) attributed to low and moderate levels. The relations between the daily number of emergency transport events due to sport injuries (EEI) and daily mean of APF integral amplitudes within the two ranges (DHAI and DHAG, resp.) along with the planetary geomagnetic index Ap are analysed using the regression models based on categorization. As shown, the high DHAI is a rather strong meteorotropic factor, being of relevance to increase in the incidence of sport injuries. The high DHAG appears to be of opposite sense on the background of low DHAI, promoting the decreased EEI number. The consideration of combined effects of the APF and GMA reveals that the negative effects of high DHAI are more pronounced in combination with low Ap levels. The results are discussed from the viewpoint of the necessity of further medico-meteorological studies using databases of most disturbed geophysical conditions.