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Laser-induced fluorescence spectroscopy (LIFS) is actively used for remote sensing of atmospheric aerosols and is currently one of the most sensitive and selective techniques for determining small concentrations of substances inside particles. The use of high-power femtosecond laser sources for LIFS-based remote sensing of aerosols contributes to the development of new-generation fluorescence atmospheric lidars since it makes it possible to overcome the energy threshold for the nonlinear-optical effects of multiphoton absorption in particles and receive the emission signal at long distances in the atmosphere. Our study is aimed at the development and experimental demonstration of the technique of nonlinear laser-induced fluorescence spectroscopy (NLIFS) based on the remote excitation of aerosol fluorescent emission stimulated by a spatially structured high-power femtosecond laser pulse. Importantly, for the first time to our knowledge, we demonstrate the advances in using stochastically structured plasma-free intense light channels (postfilaments) specially formed by the propagation of femtosecond laser radiation through a turbulent air layer to improve NLIFS efficiency. A multiple increase in the received signal of two-photon-excited fluorescence of polydisperse-dyed aqueous aerosols by the structured postfilaments is reported. [ABSTRACT FROM AUTHOR]

Scots pine (Pinus sylvestris L.) is a valuable tree species, playing an important role in maintaining the ecological and economic balance not only in Kazakhstan, but also in many countries around the world. The purpose of this study was to assess the growth rate and to identify the genotypes of the half-sib progeny of Scotch pine plus trees in order to further obtain high-quality seeds with valuable genetic traits. A molecular genetic analysis was carried out using six microsatellite and 20 isoenzyme loci on 15 Scots pine half-sib families, represented by two samples of seeds collected in the subsequent harvesting periods (planted in 1986 and 1987), that evaluated the taxonomic characteristics such as tree height and trunk diameter (DBH, measured at 1.3 meters). Families with the highest growth rate in both samples were selected as candidates for the elite group. During the SSR analysis, a decrease in the level of expected heterozygosity (0.2377-0.5362 with an average value of 0.4593) was observed in P. sylvestris L. half-sibs compared to the sample of maternal plus trees (0.5444), with similar results to that of the "founder effect". At the same time, the level of observed heterozygosity remained sufficiently high (0.3333-0.7037 with an average value of 0.4980 and 0.4556, respectively). During the isoenzyme analysis, the level of genetic variability either decreased or was similar to that of the maternal trees. Rare and unique alleles were found in seed samples of the analysed tree families. In general, this research showed that a comprehensive evaluation combining both traditional breeding methods (genetic assessment of progeny in the course of growth) and molecular genetic analysis is required for the selection of elite trees. [ABSTRACT FROM AUTHOR]

The purpose of the research is to determine the effect of ammonium nitrate fertilizer on the growth and yield of Origanum vulgare L. essential oil grown in Northern Kazakhstan. One-factor analysis proved that the introduction of ammonium nitrate positively affected the growth and yield of O. vulgare L., the yield of essential oil and the content of its individual components. Plant height increased by 19.3%, bush size - by 17.4%, yield - by 11.8%. Essential oil output of O. vulgare L. at the experimental site, compared to the control site, increased by 20% and the yield of extraction reached 0.60% and 0.48%, respectively. The largest number of components was related to monoterpenes (52.57% in the experimental section, -50.10% in the control section), the most common were γ-Terpinene, ß-Sabinene, Carvacrol and trans-ß-Ocimene. Sesquiterpene content in the experimental sample was 37.19%, compared to 38.5250% in the control sample, in which Germacrene D and Caryophyllene were the most common components. Cluster analysis showed that the essential oil composition of O. vulgare L. from Kazakhstan is similar to the composition of the essential oil of plants from Moldova, Poland, Turkey (Anatolia), Latvia and Russia. Germacrene D, Carvacrol and ß-Sabinene were the binding components of plants from Kazakhstan and Moldova. The similarity between plants from Kazakhstan and other countries in the same cluster was due to the Germacrene D content (cluster's average value was 10.1%) and the content of Spathulenol (4.9%). [ABSTRACT FROM AUTHOR]

In the flora of Kazakhstan there are many medicinal plants, of which the genus Artemisia (Asteraceae) includes 81 species. In the current study, chemical composition of essential oil from aerial parts of Artemisia austriaca Jacq. collected from different sites of Northern Kazakhstan was determined using GC-MS analysis. The chemical analysis demonstrated that the oil was dominated by oxygenated monoterpenes amounting to 39.49-59.20% with camphor (7.03-20.52%), 1,8-cineole (8.95-13.55%), α-thujone (3.16-25.78%) and β-thujone (0.87-9.92%) as major constituents. The results also suggested that there was difference in composition as well as amount among different sites depending on pH and organic matter of the soil. Further chemometric analysis using hierarchical cluster analysis (HCA) of A. austriaca essential oil compositions from the published literature as well as the composition from present study were used in order to demonstrate geographical variations in the composition of the essential oils. It showed the existence of two main clusters: mixture of α- and β-thujones (32.5±21.6%) / 1,8-cineole (13.9±7.8%) (Cluster I) and camphor (40.5±17.4%) / 1,8-cineole (19.4±9.5%) (Cluster II). [ABSTRACT FROM AUTHOR]