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The article presents the results of the research on the features of Pinus sylvestris L. condition and productivity in forest stands of the Left-Bank Forest-Steppe of Ukraine (in Kharkiv and Sumy regions) for 2006–2021. The study was carried out using the 'Forests of Ukraine' Database as of 01.01.2017, and the results of field research at 30 temporary sample plots (TSP), 3 permanent sample plots (PSP) (in 2006–2018), and 13 monitoring plots (2009–2021). Generally accepted methods and new standards were used. The dynamics of forestry and evaluation indicators of Scots pine stands at sample plots were analyzed and compared with high-productive Scots pine stands. The characteristics of natural regeneration are given. It was revealed that the age structure of pine stands is not optimal: there is an excess of middle-aged stand areas. Changes in the structure and development of managed Scots pine stands with respect to changing environmental conditions were observed for 2009–2021. Studied forest stands showed a tendency for negative changes in stand structural characteristics related to regeneration and growth. Drought mainly in combination with even medium anthropogenic impact can further worsen the health status of Scots pine stands in lowland areas of the Left-Bank Forest-Steppe of Ukraine. Thus, the formulation of forest management measures to mitigate the impact of these stress factors is needed. [ABSTRACT FROM AUTHOR]

A solar eclipse (SE) provides a researcher with a rare opportunity to follow the dynamics of the Earth's system (its shells)—the atmosphere, the ionosphere, and the magnetosphere—and variations in the geophysical fields over an interval of a few hours. Different solar eclipses induce significantly different disturbances in this system. The parameters of these disturbances depend on the onset time of a solar eclipse, the state of space weather, the season, the solar cycle phase, the geographic coordinates, and the degree of the solar disk occultation during a solar eclipse. It should be kept in mind that each of the SEs exhibits its own individual characteristics. The purpose of this paper is to analyze the results of ionosonde observations of the ionospheric disturbances accompanying the SE above the city of Kharkiv on June 10, 2021. At the city of Kharkiv, the maximal observed magnitude of the SE was Мmax ≈ 0.11 (more precisely, 0.112) and the relative area of the solar disk occultation was Аmax ≈ 4.4%. The eclipse started at 10:42 UT (13:42 LT) and ended at 12:12 UT (15:12 LT). The maximal magnitude was observed at 11:28 UT (14:28 LT). To study the features of variations in the virtual heights and the frequencies, we used a digital ionosonde located at the Radio Physical Observatory of the V. N. Karazin Kharkiv National University. The analysis of the space weather showed that, during the SE, as well as at the reference time intervals on June 6 and 9, 2021, the space weather conditions were favorable for observing wave disturbances, which is evidenced by the index value Kp ≈ 0.3. The frequency and altitude characteristics of the ionosphere obtained by vertical sounding were analyzed, and the features of the ionospheric processes, which accompanied the partial SE but were absent on the reference day, were determined. During the SE, wave activity in the ionosphere became stronger. The wave trains, which were observed at an altitude of the F2 layer maximum, had periods of 5 and 14 min, while the relative amplitudes of oscillations in the electron density were 0.6 and 1.25%, respectively. At an altitude of 240 km, the relative amplitude of waves with a period of ~14 min increased by 3%. The 14-min period pertains to the atmospheric gravitaty waves, while the 5-min period pertains to the waves of electromagnetic nature. A sharp and considerable increase (from 380 to 560 km) in the virtual height of the radio wave reflection from the F2 region was observed close to the moment of the greatest SE magnitude. A weak decrease (by less than 3.3%) in the electron density, which lagged behind the maximal eclipse magnitude by 12.5 min, was detected. The rates of the electron loss (1.33 × 10–3 s–1) and the ion production (3 × 108 m–3s–1) were estimated. [ABSTRACT FROM AUTHOR]

The analysis of the dental status in Kharkiv population newborns and neonates (Kharkiv City, Ukraine) born with macrosomia has been performed. One hundred and twenty six infants (51 girls and 75 boys) born in 2015 were examined at the age from several hours to several months. They were divided into four groups. The first group was represented by 35 infants born with macrosomia. Twenty nine infants, who had standard weight and length for their gestational age (normosomic), made up the second group. Infants who were born with perinatal hypoxic-ischemic brain damage and macrosomia composed the third group, which included 24 babies. Normosomic infants having perinatal hypoxic-ischemic brain damage belonged to the fourth group of 38 babies. Clinical and statistical methods were applied. Causes of macrosomia in the first and third groups in the sample have been analyzed. Macrosomia can imply hereditary predisposition. The birth of macrosomic newborns is determined by the mother’s weight-length index to a greater degree than by the father’s one. As it turns out, the factors associated with fetal macrosomia include multiparity, but significant influence of parents’ age, maternal obesity, the presence of gestational diabetes, or type 1 diabetes mellitus has not been detected. Dental abnormalities have been proven to occur in all four groups: twenty one infants (60%) in the first group, four infants (13.8%) in the second group, seventeen infants (70.1%) in the third group, and sixteen infants (42.1%) in the fourth group have been proven to have dental abnormalities. The study has shown the higher prevalence of anomalies in the maxillofacial area in the children who were born with macrosomia. Soft tissues anomalies (ankyloglossia, tight and low attached maxillary frenulum) are mostly associated with fetal macrosomia. Relevant evidence for the effect of oxygen deficiency (perinatal hypoxic-ischemic brain damage) in the perinatal period on the dental anomaly formation in the children born with macrosomia has not been revealed. [ABSTRACT FROM AUTHOR]