Vol 32, No 2 (2025)
- Year: 2025
- Published: 20.07.2025
- Articles: 6
- URL: https://hum-ecol.ru/1728-0869/issue/view/12983
ORIGINAL STUDY ARTICLES
Influence of solar radiation components on partial oxygen density in the surface air layer in subarctic and subtropical regions
Abstract
BACKGROUND: Solar radiation consists of electromagnetic radiation and the solar wind. It becomes nonlinear during solar flares, with increased wave radiation and the emission of large amounts of charged particles. Increased solar radiation intensity alters the Earth’s light and thermal balance and geomagnetic activity, affecting both weather and oxygen status.
AIM: To assess the effect of solar radiation components on changes in partial oxygen density in subarctic and subtropical regions, depending on the level of solar activity.
METHODS: Sunspot data were obtained from the Royal Observatory of Belgium. Solar radiation levels, the planetary magnetic index (Ap), and the local geomagnetic activity index (K) were assessed using data from the All-Russian Research Institute of Hydrometeorological Information. Partial oxygen density was calculated based on air temperature, atmospheric pressure, and relative air humidity. Data from 2007 (low solar activity) and 2001 (high solar activity) were compared. Wavelet analysis was used for mathematical processing.
RESULTS: In the North, the mesor, amplitude, and autocorrelation of solar radiation in 2001 did not differ from those recorded in 2007. In subtropical regions, the mesor and amplitude of solar radiation were significantly higher, whereas autocorrelation was lower, indicating a disruption of time series. The synchronization coefficient demonstrated a strong correlation between solar radiation and partial oxygen density in both high and low solar activity years in the North, and a weak synchronization in the subtropics during the year of low solar activity. Synchronization of the Ap and K indices in Polokwane increased as solar activity rose from very low to moderate. The synchronization coefficients for Ap and partial oxygen density, as well as K and partial oxygen density, indicated a very weak correlation between magnetic indices and partial oxygen density, regardless of solar activity. In Khanty-Mansiysk, synchronization between the Ap and K indices remained weak. The synchronization coefficient for Ap and partial oxygen density showed a non-significant increase with rising solar activity, whereas synchronization between K and partial oxygen density decreased from weak to very weak as solar activity increased.
CONCLUSION: During the year of low solar activity, both geographic regions showed a significant correlation between solar radiation fluctuations and partial oxygen density. In subtropical regions, increasing solar activity was associated with a weaker correlation between solar radiation and partial oxygen density. Significant synchronization between fluctuations in partial oxygen density and planetary or local magnetic activity ranged from weak to very weak, regardless of solar activity levels or geographic latitude.
80-89
The Effect of Indoor Plants on Indoor Air Quality in Child Care Centers
Abstract
BACKGROUND: In the modern settings, air quality is critical to children’s health. Preschool education has a significant impact on children’s health, which is determined by child care centers' compliance with sanitary and epidemiological regulations and established hygienic standards. According to Russian and international studies, low air quality, poor microclimate, and reduced comfort in indoor environments caused by carbon dioxide have a negative impact on children's functional status. This reduces functional capacity and cognitive performance while also compromising the immune system, which significantly increases the risk of morbidity in children. Notably, there are currently no standards for carbon dioxide (CO2) levels; as a result, it is a risk factor in institutions where children are housed both temporarily and regularly.
AIM: To evaluate the use of indoor plants to improve indoor air quality in child care centers.
METHODS: Microclimatic indicators and air quality were monitored in two playrooms of the Raduga combined-type kindergarten. A specific type of indoor plants was used; the selected plants were safe and harmless to children, with proven antibacterial, air-sanitizing, and gas-absorbing properties. EClerk-Eco-RHTC devices (Novosibirsk, Russia) were installed in the observation and control groups to continuously measure, monitor, and regulate air parameters essential for human health (temperature, relative humidity, CO2 concentration), alerting users when any value exceeded preset thresholds.
RESULTS: The air quality study in the Raduga kindergarten showed that the recommended indoor plants in rooms where children stay for extended periods provided a significant decrease in carbon dioxide levels in the observation group compared to the control group: by 1.3-fold (Kruskal–Wallis test, p < 0.05) and 1.2-fold (Kruskal–Wallis test, p < 0.05), respectively, when plants with leaf surface areas of 1.7 m2 and 2.5 m2 were placed in a 48 m2 room.
CONCLUSION: The effectiveness of improving air quality in playrooms of child care centers depends on the leaf surface area of the recommended plants and their rational distribution, taking into account the effective radius of impact. Indoor plants with a combination of phytoncidal, gas-absorbing, and transpiring properties improve indoor air quality and reduce CO2 concentrations in child care centers.
90-99
Quantitative Assessment of Traditional and Imported Meat Consumption by Indigenous and Local Caucasian Populations of the Modern Arctic
Abstract
BACKGROUND: A healthy, balanced diet is essential for preserving metabolic health in high-latitude environments. Indigenous peoples’ traditional lifestyles have shifted from nomadic to settled due to socioeconomic changes caused by industrial growth and urbanization in northern regions. This transition has affected dietary patterns and, consequently, metabolic health.
AIM: To conduct a comparative quantitative assessment of traditional and imported meat product consumption by indigenous and local Caucasian populations of the modern Arctic.
METHODS: During field expeditions to the Yamalo-Nenets and Nenets Autonomous Okrugs, 839 people’s dietary habits were assessed using a questionnaire-based survey. Retrospective data were collected on the consumption of traditional and imported meat products over the preceding 12 months among both indigenous (nomadic and settled) and local Caucasian Arctic residents.
RESULTS: Indigenous populations consumed more traditional meat products, whereas local Caucasian populations consumed more imported meat, both lean and fatty. Among indigenous populations, nomadic people consumed significantly more traditional meat, whereas settled people consumed more fatty imported meat. There were no significant differences in processed meat consumption between the three groups.
CONCLUSION: The abundance of imported meat products in the diet, previously uncharacteristic of the Russian Arctic’s indigenous peoples, has not completely replaced traditional cuisine. Among indigenous populations, nomadic people consume meat in ways that are more similar to traditional diets than their settled counterparts. However, retrospective data indicate a decline in the consumption of reindeer meat, a dietary staple among the Nenets. Therefore, to ensure a high quality of life and good health, indigenous populations of northern regions should stick to their centuries-old traditional dietary patterns, maintaining a high proportion of locally sourced foods.
100-109
Prevalence of natural ABO antibodies in donors in Surgut
Abstract
BACKGROUND: The physiological status of a population can be assessed through the adaptive function of maintaining internal homeostasis, particularly by studying the activity of natural antibodies. The population-specific ecological variability in antibody production is of interest for both population physiology and the advancement of applied transfusion medicine and transplantation.
AIM: To assess the prevalence of natural ABO antibody titers in donors in Surgut.
METHODS: A single-center, cross-sectional, observational study was conducted. The study included donors from Surgut. The presence and activity of natural complete ABO anti-erythrocyte α (anti-A) and β (anti-B) antibodies were assessed using slide titration with standard A(II) and B(III) erythrocytes and isotonic sodium chloride solution. The prevalence of antibody titers was calculated as a percentage.
RESULTS: A total of 14,223 donor blood samples were analyzed. In type O(I) blood donors, natural antibody activity began at titers of 1:2 and 1:4, with some reaching titers as high as 1:512. The most prevalent titers in type A(II) blood donors were 1:8 in males and 1:16 in females, whereas in type B(III) blood donors, a 1:32 titer was most common in both sexes. The highest titers reported in the A(II) and B(III) groups were 1:256. Titer distributions were similar in males and females, with an overall tendency toward lower titers in 2023. A high incidence of 1:8 and 1:16 titers was reported in males and females, respectively.
CONCLUSION: Distinct patterns in the prevalence of natural ABO antibody titers were identified in 2015–2017 vs. 2023, a period with post-COVID-19 immune response transformation. These differences are likely due to previous SARS-CoV-2 infection and its effects on immune system function. The findings indicate that Surgut donors' immune systems actively produce natural ABO antibodies, which is important for assessing the physiological structure of populations living in specific environments.
110-122
Ventricular repolarization in apparently healthy young men under short-term normobaric isocapnic and hypercapnic hypoxic exposure
Abstract
BACKGROUND: The effects of hypoxic exposure on the human cardiorespiratory system have been extensively studied. Combined hypoxic and hypercapnic exposure has been shown to reduce the severity of adverse outcomes associated with oxygen deficiency across all functional systems, while also improving subjective tolerance to acute hypoxia.
AIM: To assess cardiac electrical activity during the ventricular repolarization phase under exogenous normobaric hypoxic exposure with different inspired carbon dioxide levels in apparently healthy, untrained individuals.
METHODS: A prospective, single-center, experimental study was conducted. The study included apparently healthy, untrained young men. Exclusion criteria: chronic pulmonary or cardiovascular diseases and recent acute respiratory viral infections. Participants were randomly assigned to one of two groups based on the type of exposure: exogenous isocapnic hypoxia (Group 1) or exogenous hypercapnic hypoxia (Group 2). Isocapnic and hypercapnic hypoxia were simulated by breathing through a facial mask for 15 minutes. The cardiac electric field was used to assess the amplitude and temporal characteristics of positive and negative extrema during the ventricular repolarization phase based on lead II electrocardiogram findings. The duration of QT, J–Tpeak, and Tpeak–Tend intervals with Bazett's correction was measured.
RESULTS: Isocapnic hypoxia was found to cause more pronounced changes in SpO2 and heart rate compared to hypercapnic hypoxia. At comparable SpO2 levels, analysis of the temporal characteristics of ventricular repolarization demonstrated that the hypercapnic component of the hypoxic gas mixture reduced changes in the duration of nearly all examined electrocardiogram intervals.
CONCLUSION: The study of ventricular repolarization under hypoxic exposure with various CO2 levels found that isocapnic hypoxia had a more pronounced stress effect on cardiac electrical activity than hypercapnic hypoxia in apparently healthy young men.
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Prevalence of Anxiety and Depression Symptoms and Their Association with Sleep Quality in Patients with Hypertension
Abstract
BACKGROUND: In recent years, substantial evidence has accumulated regarding the negative impact of psychoemotional stress, sleep disorders, and anxiety and depressive disorders on the course of arterial hypertension, as reflected in national guidelines. However, in real-world clinical practice, these aspects are often assessed subjectively and rarely incorporated into the diagnosis; as a result, they frequently receive insufficient attention and are not addressed properly.
AIM: To assess the prevalence of subclinical and clinically significant anxiety and depression symptoms, as well as their association with sleep quality in patients with hypertension.
METHODS: A single-center, observational, cross-sectional study was conducted. The study included patients admitted for follow-up inpatient examination and treatment at the Department of Propaedeutics of Internal Diseases, S.M. Kirov Military Medical Academy, from 2021 to 2024. During their first days in the hospital, patients completed validated questionnaires assessing psychoemotional status, sleep disorders, and risk of obstructive sleep apnea. The questionnaires included the Hospital Anxiety and Depression Scale, the Insomnia Severity Index, the STOP-BANG Risk Score for Obstructive Sleep Apnea, and the Epworth Sleepiness Scale.
RESULTS: A total of 348 patients were surveyed, with a mean age of 49.5 ± 20.6 years. The majority of participants were male (83.3%), whereas females comprised 16.7%. Symptoms of subclinical and clinically significant anxiety and depression were reported in 112 patients (32.2%) and 132 patients (37.9%), respectively. A high risk of obstructive sleep apnea was identified in 228 patients (65.5%), whereas 282 patients (81.1%) had moderate sleep disorders. The severity of anxiety and depression moderately correlated with sleep quality (ρ = 0.51 and 0.50, respectively; p < 0.001) and daytime sleepiness (r = 0.43 and 0.57, respectively; p < 0.001). Individuals with moderate sleep disorders were 12.88 times more likely to have depression symptoms (95% CI: 4.6–36.4) and 9.62 times more likely to have anxiety symptoms (95% CI: 3.40–27.20); these differences were significant. Moreover, there were significant differences in anxiety and depression severity in patients with exertional angina and a high risk of obstructive sleep apnea, regardless of sex. In female patients, significant differences in anxiety severity were reported (p < 0.05).
CONCLUSION: The findings show that patients with hypertension have a high prevalence of cardiovascular risk factors, including psychoemotional disorders, sleep disorders, and obstructive sleep apnea, emphasizing the importance of comprehensive history taking and using specialized questionnaires in routine clinical practice.
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