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The front-end is a section of the synchrotron radiation (SR) beamline intended to interface the vacuum, radiation, and optical conditions of the SR source with those of the experimental stations. This work presents thermal analyses of key front-end components developed for undulator beamlines 1-1 and 1-2 of the Siberian Circular Photon Source (SKIF). The expected output power of the SR beam from a linear undulator is 7.1 kW. The finite element method implemented in the COMSOL® Multiphysics 6.2 software package, along with the method of the non-uniform power density distribution, is used for simulations. The paper reports the development of front-end components and 3D modeling results of temperature fields and mechanical stresses under continuous thermal loading in ultra-high vacuum conditions. Calculations are carried out for the following components: fixed mask, movable photon shutter, adjustable mask, radiation shutter, diamond vacuum windows, thermal filters, and SR beam monitors. The obtained results demonstrate that the designed cooling systems for the front-end elements efficiently dissipate the incoming thermal power of the synchrotron beam and ensure their reliable operation.

For metals, soil and rocks, a creep model non-associated with the Tresca and Mohr-Coulomb yield surfaces is discussed. The constitutive laws for creep in the model contain angles of internal friction and dilatancy. The authors propose a procedure for finding angles of internal friction and dilatancy using creep curves obtained from testing cylindrical samples. Determination of the time of failure at different irreversible strain rates and different initial stress levels uses the deformation-based and energy-based failure criteria applicable to both uniform and non-uniform stress states under long-term loading.

The analysis of dynamic events in the earth’s crust should take into account internal mechanical losses (energy dissipation) in rocks. Such dynamic events often have a frequency under 1 Hz. Internal mechanical losses are estimated in terms of the dissipation factor Q ^-1. Rayleigh damping represents the dissipation factor with respect to the direct and inverse dependence on frequency. The authors performed three-point bending tests of rock samples of different types and genesis. The dissipation factors are calculated for various frequencies of deformation. The empirical dependences of the dissipation factor on the frequency in a range of 0.003-0.100 Hz are approximated by Rayleigh damping. The coefficients of variation and determination are calculated to define conformity between the experiment and model data, the conclusion on the good agreement with the Rayleigh model is made, and the causes of differences between experimental and theoretical results are listed.

Thermal environment in vertical mine shafts has a significant influence on the shaft support and reinforcement, and on the safety of the while hoisting facility. Fluctuation of air flow temperature causes thermal deformation of structural elements in the shafts. Subzero temperature air enters mine shafts in the winter season because of deficient heating of air supply shafts and as a result of air flow reversal in ventilation shafts. As a consequence, tubing support in the shafts experiences cooling, the tubing joints open, and water inflow in the shaft goes over and above a guideline value, which can initiate an accident. The authors analyze the impact of subzero temperatures on the opening of tubing joints after change in the stress-strain behavior of the tubing ring-concrete lining-rock mass system. The developed and implemented numerical model of the mentioned geotechnical system determines patterns of temperatures and deformations in tubing rings in the periods of exposure to cold.

Floras of mountain territories are of interest due to species richness and а large number of endemic and rare species. However plant checklists published in the second half of the last century turned out to be unsuitable for usage due to modern taxonomic treatments, reidentification of herbarium specimens and results of additional field investigations. The purpose of this work was to compile an actual checklist of the flora of the Eastern Tannu-Ola Range, in which takes into account literary data, the current taxonomic and nomenclature points of view, the results of field researches of the author and other botanists, as well as reidentification of specimens, stored in the herbaria of the Central Siberian Botanical Garden SB RAS (NS, NSK). The actual checklist comprises 1028 species and subspecies of vascular plants which belong to 373 genera and 86 families. Of these, 119 species are listed for the Eastern Tannu-Ola Range for the first time. The 10 biggest families are Poaceae (124 species and subspecies), Asteraceae (121), Rosaceae (66), Fabaceae (62), Ranunculaceae (59), Cyperaceae (55), Caryophyllaceae (43), Brassicaceae (41), Lamiaceae (33) and Scrophulariaceae (31). All the ten largest families are the same as the ten largest families of the Boreal Region and neighbouring Western Tannu-Ola Range and Tsagan-Shibetu Range. However the flora of the Eastern Tannu-Ola Range belongs to Rosaceae-type (Central-European) by the first three largest families (Poaceae, Asteraceae, Rosaceae), while floras of Western Tannu-Ola and Tsagan-Shibetu Ranges belong to Fabaceae-type (Mediterranian-Mongolian) by the first three largest families (Asteraceae, Poaceae, Fabaceae), this points out on the position of the ranges of the Southern Tuva on the world watershed and the proximity of their floras to both North Asian and Central Asian floras. Twenty six species of the flora included into the Red Data Book of the Russian Federation and/or the Red Data Book of the Tyva Republic.

A review of the scientific literature devoted to the study of Astragalus glycyphyllos in various biological and chemical aspects are presented. Currently, studies of the native chemical complex of this type of Astragalus are relevant, with the establishment of the structure of its components, pharmacotherapeutic activity, useful properties and potential uses of A. glycyphyllos not only as a model object in biomedical research, but also, for the conditions of Russia, as analogues of pharmacopoeial types of Astragalus. The results obtained by scientists from different countries, as well as the experience of using A. glycyphyllos in folk medicine from different countries, serve as the basis for the multipurpose use of raw materials of this type of astragalus in pharmacy and medicine. Currently, studies of the recently established neuroprotective activity of extracts and individual compounds of the native A. glycyphyllos complex as potential drugs for the treatment of certain neurodegenerative diseases are becoming particularly relevant.

In a stable climate, the seasonal development of autochthonous plants is well synchronized with the local climate, which determines the stability of their fruiting. However, after the onset of global warming, the periodicity of crop formation began to change in many species, so there was a need to study the causes of this phenomenon. Using the example of Pinus sibirica Du Tour, an economically important nut-bearing species with uneven seed production over the years, the influence of short-term weather anomalies at the stage of cone formation and late spring frosts in the year of development of annual cones is considered. The research was carried out on the example of 180-200-year-old pine trees near the village in the south of Western Siberia. The harvest of mature cones was taken into account for the period 1990-2023. The number of cones laid was determined retrospectively by traces of fallen organs on the bark of shoots. At the same time, meteorological data for the same period obtained from the nearest weather station were analysed. It was found that the optimal conditions for cone setting are average daily temperatures no higher than +17.5 °C in the first ten days of August. The number of cones a depended on the spring weather in the year of growth and differentiation of annual cones and negatively correlated with the sum of active temperatures above +5 °C accumulated before the late spring frost. It has been suggested that the climatically determined continued increase in heat supply in the spring against the background of delayed frosts is fraught with an increase in the negative trend in the dynamics of seed production.

Saposhnikovia divaricata (Turcz.) Schischk. is endemic to Southeast Asia. Biologically active substances have been found in the roots of plants. Consequently, a massive and unregulated withdrawal of S. divaricata from plant communities has been noted, which may lead to a disruption in the balance of genes in cenopopulations of this species. The assessment of the genetic variability of natural populations and the development of S. divaricata cultivation technology is relevant. The optimal ISSR-PCR protocol for S. divaricata has been developed in this study: the most informative primers were selected, conditions for their specific amplification were selected, the polymorphism of ISSR markers in the natural population and plants of the 3-rd generation introducers were analyzed. We studied 16 samples from the natural population of Siberia (Republic of Buryatia) and 15 samples of introduced plants grown at the exposition “Rare and endangered species of plants of Siberia” of the Central Siberian Botanical Garden SB RAS (Novosibirsk). Total DNA was isolated by a modified CTAB method. Of the tested 17 ISSR primers, 4 informative ones for S. divaricata were selected, for which a comparative analysis of genetic variability was carried out. As a result, genetic distances, the level of polymorphism, intra-and inter-population variability were determined. We identified 114 PCR fragments ranging in length from 220 to 3000 bp, 108 of which were polymorphic (94.7 %). Using various statistical programs (TREECON 1.3b, GenALEx 6.51), it was found that the natural population of S. divaricata is characterized by high genetic variability: the Shannon indexis 0.48 ± 0.02, intrapopulation variability is 89 %. We have established that ISSR-PCR is a method for fast and accurate analysis of morphologically close populations of S. divaricata for the detection of genetic changes. For rapid screening, it is sufficient to use one of the four markers (HB12, HB14, 17899A, 17899B), which have shown high efficiency. As a result of the study, it was found that the genetic diversity of S. divaricata did not change under the conditions of introduction during the change of generations compared with the original natural population.

The article focuses on the diversity, ecology, and distribution of steppe on solonetz soils in the South-Minusinsk and North-Minusinsk basins. The steppes were classified into two classes: Agropyretea cristati and Festuco-Brometea. The first class, Agropyretea cristati, includes the following associations: Achnathero sibirici-Stipetum krylovii(variant Iris biglumis), Artemisio frigidae-Stipetum krylovii (variant Achnatherum splendens), Zygophyllo pinnati-Stipetum krylovii , and Allio ramosi-Stipetum krylovii(variant Leymus ramosus). The second class, Festuco-Brometea, is represented by the association Artemisio - Caricetum (variant Plantago salsa). Two ecological series of steppes were identified, with their diversity correlating with the soil’s richness-salinization gradient. The first series begins with the Achnathero sibirici-Stipetum krylovii association and its halophytic variant Iris biglumis . This is followed by the Artemisio glaucae-Caricetum pediformis association (variant Plantago salsa ) and concludes with communities on solonetz soils represented by the Galatello biflorae-Puccinellietum tenuissimae association. The second series starts with the Zygophyllo pinnati-Stipetum krylovii association, transitioning into the Allio ramosi-Stipetum krylovii and Artemisio frigidae-Stipetum krylovii associations, which are replaced by their halophytic variants: Leymus ramosus and Achnatherum splendens. This series ends with the more humid Artemisio glaucae-Caricetum pediformis association. The Zygophyllo pinnati-Stipetum krylovii steppes are found in the South-Minusinsk basin, where they form complexes with communities on solonetz soils, as well as with the Allio ramosi-Stipetum krylovii and Artemisio frigidae-Stipetum krylovii steppes. Halophytic variants of dry steppes (variants: Leymus ramosus and Achnatherum splendens) are observed in isolated small areas of the basin. The Artemisio glaucae-Caricetum pediformis association (variant Plantago salsa) is common in the North-Minusinsk basin, where it forms combinations with the Achnathero sibirici-Stipetum krylovii steppes in the landscape. Steppes on solonetz soils do not form large continuous areas in the South-Minusinsk and North-Minusinsk basins. Their distribution is closely associated with depressions around salt lakes, where the vegetation has been significantly impacted by heavy recreational use. As a result, these steppe communities are highly disturbed.

The paper presents the data on syntaxonomical diversity of forest vegetation of the «ribbon» forests of the Ob-Irtysh watershed. The dataset of 87 original and 152 previously published relevés was analyzed. To segregate the types of communities the TWINSPAN and the manual sorting in the software package IBIS 7.2 were applied. The ordination of syntaxa based on plants indicator values was conducted. The prevalent role of soil moisture in the differentiation of forest communities was shown. Forest vegetation is represented by 6 variants, 3 subassociations, 11 associations, 4 alliances and 4 orders from 4 classes. The class Koelerio glaucae-Pinetea sylvestris includes 3 associations and represents psammophytic pine forests with sparse herb layer, which is dominated by steppe and meadow-steppe plants. The group of most xerophytic communities with the predominance of psammophytes was described as a new association (Table 1). Ass. Stipo borysthenicae-Pinetum sylvestris Chupina et Korolyuk ass. nov. (Table 2, rel. 1-22), holotypus - Table 2, rel. 13 (field no. 96-023): Republic of Kazakhstan, Abayskaya Oblast, Beskaragajskiy district, 4 km north of the village Kanonerka, 12.06.1996, author - A.Yu. Korolyuk. D. s.: Alyssum tortuosum, Astragalus altaicus, Cleistogenes squarrosa, Eremogone biebersteinii, Erysimum canescens, Helichrysum arenarium, Jurinea schischkiniana, Kochia laniflora, Scorzonera ensifolia, Silene borysthenica, Stipa borysthenica, Syrenia siliculosa. Pine forests of the association are common in the southern parts of the “ribbon” forests in the steppe zone (Fig. 3). The communities occupy the gentle slopes as well as the tops of sand dunes. The density of the pine forest stand canopy varies widely and depends on the anthropogenic disturbance intensity. The facultative and obligate psammophytes predominate in the herb layer. The dominants are Carex supina , C. ericetorum , and Koeleria glauca. The class Vaccinio-Piceetea unites mesophytic pine forests with a developed moss-lichen layer. They relate to well-drained habitats with acidic soils. The class includes 5 associations that are widespread in the Burlinskiy pine forest and we had occured the class communities in other “ribbon” forests as well. Mesophytic pine forests with rich herb layer of the class Brachypodio pinnati-Betuletea pendulae include two associations, which were developed on the relatively rich soils. The swamped forest communities belong to the class Alnetea glutinosae. The both classes so far are pointed out for the Burlinskiy pine forest only.