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Pleistocene water bodies have been studied using the paleolimnological approach, which traces environmental changes using particular subfossils as ecological proxies, rather than analysis of the paleocommunities themselves. Within a given taphocoenosis, the presence and quantity of animals are related to environmental conditions rather than to community types where relationships between taxa are stabilized during their long-term co-occurrence and are (at least partially) more important than the particular environmental conditions at the time of deposition, which may have experienced significant seasonal and inter-seasonal variations. Here, we analyze Branchiopoda (Crustacea) of two paleolocalities in the Transbaikalian Region of Russia: Urtuy (MIS3) and Nozhiy (older than 1.5 million years). Cladocerans Daphnia (Ctenodaphnia) magna, D. (C.) similis, D. (Daphnia) pulex, Ceriodaphnia pulchella-reticulata, C. laticaudata, Simocephalus sp., Moina cf. brachiata, M. macropopa clade, Chydorus cf. sphaericus, Capmtocercus sp. and anostracans Branchinecta cf. paludosa, and Streptocephalus (Streptocephalus) sp. are found in two localities. With the exception of the last taxon, which now occurs in the southern Holarctic, all other taxa inhabit the Transbaikalian Region. Within Eurasia, the steppe zone has the greatest diversity of large branchiopods and a high diversity of some cladocerans, such as subgenus Daphnia (Ctenodaphnia) and Moina sp. Here we demonstrated that the branchiopod community in shallow steppe water bodies has been unchanged since at least the Pleistocene, demonstrating long-term morphological and ecological stasis.

Diverse epidermal appendages including grouped filaments closely resembling primitive feathers in non-avian theropods, are associated with skeletal elements in the primitive ornithischian dinosaur Kulindadromeus zabaikalicus from the Kulinda locality in south-eastern Siberia. This discovery suggests that “feather-like” structures did not evolve exclusively in theropod dinosaurs, but were instead potentially widespread in the whole dinosaur clade. The dating of the Kulinda locality is therefore particularly important for reconstructing the evolution of “feather-like” structures in dinosaurs within a chronostratigraphic framework. Here we present the first dating of the Kulinda locality, combining U-Pb analyses (LA-ICP-MS) on detrital zircons and monazites from sedimentary rocks of volcaniclastic origin and palynological observations. Concordia ages constrain the maximum age of the volcaniclastic deposits at 172.8 ± 1.6 Ma, corresponding to the Aalenian (Middle Jurassic). The palynological assemblage includes taxa that are correlated to Bathonian palynozones from western Siberia, and therefore constrains the minimum age of the deposits. The new U-Pb ages, together with the palynological data, provide evidence of a Bathonian age—between 168.3 ± 1.3 Ma and 166.1 ± 1.2 Ma—for Kulindadromeus . This is older than the previous Late Jurassic to Early Cretaceous ages tentatively based on local stratigraphic correlations. A Bathonian age is highly consistent with the phylogenetic position of Kulindadromeus at the base of the neornithischian clade and suggests that cerapodan dinosaurs originated in Asia during the Middle Jurassic, from a common ancestor that closely looked like Kulindadromeus . Our results consequently show that Kulindadromeus is the oldest known dinosaur with “feather-like” structures discovered so far.

According to pollen of terrestrial vegetation and micro remains of algae in the bottom sediments of the Lake Bayn-Tsagan reconstructed the vegetation of southeastern Transbaikalia in the Late Holocene. The palynological record showed a change in the lake level against the background of the absence of a dramatic change in vegetation and significant climate changes. During the accumulation of a 30 cm layer of bottom sediments, a threefold shallowing of this reservoir was recorded. In dry years, the level of the first aquifer below the surface decreased, the lake became shallow, and the abundance of higher macrophyte vegetation was overgrown with Staurastrum algae. In wet years, when the groundwater level rose, significant watering occurred. Due to increased surface runoff, the turbidity of the water in the lake increased. This contributed to an increase in the density of phytoplankton with Botryococcus .

The North Caucasus played a key role during the ancient colonization of Eurasia and the formation of its cultural and genetic ancestry. Previous archeogenetic studies described a relative genetic and cultural continuity of ancient Caucasus societies, since the Eneolithic period. The Koban culture, which formed in the Late Bronze Age on the North Caucasian highlands, is considered as a cultural “bridge” between the ancient and modern autochthonous peoples of the Caucasus. Here, we discuss the place of this archeological culture and its representatives in the genetic orbit of Caucasian cultures using genome-wide SNP data from five individuals of the Koban culture and one individual of the early Alanic culture as well as previously published genomic data of ancient and modern North Caucasus individuals. Ancient DNA analysis shows that an ancient individual from Klin-Yar III, who was previously described as male, was in fact a female. Additional studies on well-preserved ancient human specimens are necessary to determine the level of local mobility and kinship between individuals in ancient societies of North Caucasus. Further studies with a larger sample size will allow us gain a deeper understanding of this topic.

The aim of this study was to investigate the levels of various tryptophan metabolites in patients with alcoholic liver disease (ALD) and metabolic-associated fatty liver disease (MAFLD) at different stages of the disease. The present study included 44 patients diagnosed with MAFLD, 40 patients diagnosed with ALD, and 14 healthy individuals in the control group. The levels of tryptophan and its 16 metabolites (3-OH anthranilic acid, 5-hydroxytryptophan, 5-methoxytryptamine, 6-hydroxymelatonin, indole-3-acetic acid, indole-3-butyric, indole-3-carboxaldehyde, indole-3-lactic acid, indole-3-propionic acid, kynurenic acid, kynurenine, melatonin, quinolinic acid, serotonin, tryptamine, and xanthurenic acid) in the serum were determined via high-performance liquid chromatography and tandem mass spectrometry. In patients with cirrhosis resulting from MAFLD and ALD, there are significant divergent changes in the serotonin and kynurenine pathways of tryptophan catabolism as the disease progresses. All patients with cirrhosis showed a decrease in serotonin levels (MAFLDp = 0.038; ALDp < 0.001) and an increase in kynurenine levels (MAFLDp = 0.032; ALDp = 0.010). A negative correlation has been established between serotonin levels and the FIB-4 index (p < 0.001). The decrease in serotonin pathway metabolites was associated with manifestations of portal hypertension (p = 0.026), the development of hepatocellular insufficiency (p = 0.008) (hypoalbuminemia; hypocoagulation), and jaundice (p < 0.001), while changes in the kynurenine pathway metabolite xanthurenic acid were associated with the development of hepatic encephalopathy (p = 0.044). Depending on the etiological factors of cirrhosis, disturbances in the metabolic profile may be involved in various pathogenetic pathways.

We performed lithogeochemical and biostratigraphical studies of the core from the hole 8182 in the Northern paleovalley of Vitim Plateau. According to lithogeochemical characteristics of the sediments in the section, 5 members were found out. Three lower ones characterize the Dzhilinda suite, two upper ones – the Khoygot stratum. The analysis of biodiversity and fossil diatom algae distribution in the core resulted in revealing of 137 species and varieties of diatom algae related to 50 genera. Four diatom zones (DZ) were established by appearing or disappearing of index species. Ecological and geographic analysis showed domination of planktonic, indifferent, cosmopolite species. Palynological analysis revealed three pollen members with reconstruction of vegetation of forest type reflecting the vector of cooling and climate change from moderately warm one in Middle-Late Miocene to moderately cool in Early Pliocene.

Reconstruction of climate change in Central Asia over the last millennium with an annual resolution was made using geochemical and biological proxy in lake bottom sediments and tree-ring data. We investigated the lake in Central Asia- Teletskoe (Altai), Kucherla (Altai), Baikal, Arahlei (Chita) - and adjacent areas. Cores of bottom sediments were investigated by method of scanning X-ray fluorescent analysis with synchrotron radiation with the spatial resolution of 0.1 mm. It corresponds to the time resolution ~ 0.2-0.5 year. At each point analyzed more than 30 trace elements from K to U. Geochemical proxy of terrigenous, organogenous and aerosol components of sediments well correlated with regional meteodata for the last 100-150 years. Time series of lithological-geochemical indicators of climate change based on dating by 14C, 137Cs and 210Pb was calibrated by instrumental hydrometeorological data. We used tree-ring series together with element contents as an additional proxy for calculation of transfer function, considering that tree-ring series are response to summer temperature in this climatic zone. Annual temperature and precipitation change for the Central Asia region (0 - 1000 years ago) have been reconstructed using the transfer functions such as: time series proxy=function (temperature, precipitation).