Deuterated molecules in regions of high-mass star formation

We present the results of our studies of deuterated molecules (DCN, DNC, DCO$^+$, N$_2$D$^+$ and NH$_2$D) in regions of high-mass star formation, which include a survey of such regions with the 20-m Onsala radio telescope and mapping of several objects in various lines with the 30-m IRAM and 100-m MPIfR radio telescopes. The deuteration degree reaches $\sim$10$^{-2}$ in these objects. We discuss its dependencies on the gas temperature and velocity dispersion, as well as spatial distributions of deuterated molecules. We show that the H$^{13}$CN/HN$^{13}$C intensity ratio may be a good indicator of the gas kinetic temperature and estimate densities of the investigated objects.Comment: 8 pages, 4 figures, to be published in Proceedings of Science (Proceedings of the conference "The Multifaceted Universe: Theory and Observations - 2022", 23-27 May 2022, SAO RAS, Nizhny Arkhyz, Russia

Taphonomic phenomenon of ancient hair from Glacial Beringia:perspectives for palaeoecological reconstructions

An accumulation of mammoth hair, discovered in the Bol'shaya Chukochya River valley (northeast Yakutia, Russia), was found to contain remains of terrestrial and aquatic organisms, including plants, insects, crustaceans, birds and mammals. Radiocarbon dating indicated that this post-mortem taphocoenosis represented multiple time periods. The mammoth hair was dated to older than 45 ka BP, the plants were dated to 12 750 +/- 50 a BP (which corresponds to a shift in the environmental conditions and landscapes during the formation of thermokarst in northeastern Russia) and the bird feathers were dated to 4115 +/- 40 a BP. A scenario of the formation of this fossil assemblage is proposed, covering the MIS 3-1 time range. The hair also yielded various Arctic branchiopod crustaceans, which inhabit shallow temporary water bodies and therefore are important for reconstruction of palaeoenvironments. The cladoceran subgenus Daphnia (Ctenodaphnia), currently absent from the Asian part of Beringia, is reported from this region for the first time. The study demonstrates that the discovered permafrostpreserved hair is a unique repository of Ice Age organisms.</p

Spectroscopic analysis of metabolic profile in patients with relapsed multiple sclerosis

Introduction. Managing patients with relapsing-remitting multiple sclerosis (RMS) remains a pressing issue. Objective. To detect the reversible metabolic changes of the brain matter in patients with clinically exacerbated RMS and to follow them up after intravenous glucocorticoid (IVGC) treatment. Materials and methods. Neurological examination and neuroimaging in the RMS patients included expanded disability status scale (EDSS) scoring, conventional brain magnetic resonance imaging (MRI), and proton nuclear magnetic resonance spectroscopy (1H-NMR spectroscopy) before and after IVGC treatment. Multivoxel 1H-NMR spectroscopy was used to assess metabolism in the centra semiovale and cingulate gyri. Results. Based on the multivoxel 1H-NMR spectroscopy, relative metabolite concentrations in the grey and white matter statistically differed within the study cohort before and after the IVGC treatment. The N-acetylaspartate/choline ratio significantly recovered and the choline/creatine ratio decreased in the anterior cingulate gyri in 27% of patients. The brainstem function score significantly improved in the metabolic response group as compared to the non-metabolic response group. Conclusion. We should study the potential predictors of RMS activity and the IVGC response to select the RMS relapses when pulse-therapy with IVGCs is definitely indicated. Spectroscopy may reveal RMS pathogenesis variability earlier than conventional MRI

An ancient bison from the mouth of the Rauchua River (Chukotka, Russia)

An incomplete carcass of an extinct bison, Bison ex gr. priscus, was discovered in 2012 in the mouth of the Rauchua River (69°30'N, 166°49'E), Chukotka. The carcass included the rump with two hind limbs, ribs, and large flap of hide from the abdomen and sides, several vertebrae, bones of the forelimbs and anterior autopodia, stomach with its contents, and wool. The limb bones are relatively gracile, which is unusual in bison, and a SEM study of the hair microstructure suggests higher insulating capacity than in extant members of the genus. Additionally, mitochondrial DNA analyses indicate that the Rauchua bison belonged to a distinct and previously unidentified lineage of steppe bison. Two radiocarbon dates suggest a Holocene age for the bison: a traditional 14C date provided an estimate of 8030±70 14C yr BP (SPb-743) and an AMS radiocarbon date provided an age of 9497±92 14C yr BP (AA101271). These dates make this the youngest known bison from Chukotka. Analysis of stomach contents revealed a diet of herbaceous plants (meadow grasses and sedges) and shrubs, suggesting that the early Holocene vegetation near the mouth of the Rauchua River was similar to that of the present day: tundra-associated vegetation with undersized plants

Origin and spread of human mitochondrial DNA haplogroup U7

Human mitochondrial DNA haplogroup U is among the initial maternal founders in Southwest Asia and Europe and one that best indicates matrilineal genetic continuity between late Pleistocene hunter-gatherer groups and present-day populations of Europe. While most haplogroup U subclades are older than 30 thousand years, the comparatively recent coalescence time of the extant variation of haplogroup U7 (~16–19 thousand years ago) suggests that its current distribution is the consequence of more recent dispersal events, despite its wide geographical range across Europe, the Near East and South Asia. Here we report 267 new U7 mitogenomes that – analysed alongside 100 published ones – enable us to discern at least two distinct temporal phases of dispersal, both of which most likely emanated from the Near East. The earlier one began prior to the Holocene (~11.5 thousand years ago) towards South Asia, while the later dispersal took place more recently towards Mediterranean Europe during the Neolithic (~8 thousand years ago). These findings imply that the carriers of haplogroup U7 spread to South Asia and Europe before the suggested Bronze Age expansion of Indo-European languages from the Pontic-Caspian Steppe region

An innovative approach to ex vitro rooting and acclimatization of Fragaria × ananassa Duch. microshoots using а biogenic silica- and green-tea-catechin-based mechanocomposite

A new approach for rapid ex vitro rooting and acclimatization of Fragaria × ananassa micropropagated plantlets of two cultivars (“Alpha” and “Festivalnaya”) has been developed using a mechanocomposite based on biogenic silica and green-tea catechins. Two different mechanocomposite treatments were studied: dipping the cut ends of microshoots in the mechanocomposite powder (the dry dip method) and single watering with solutions at concentrations of 0.3, 1.0, and 3.0 g L⁻¹. These variants were compared with pulse treatment of microplants with 30 mg L⁻¹ indole-3-acetic acid (IAA) for 4 h and a control group of microshoots that were moistened with hormone-free ¼-strength MS medium. The frequencies of ex vitro rooting at the end of the acclimatization period (30 d) varied from 24.8 to 99.7%. The dry dip treatment was best (rooting frequency about 100%) with up to 7.15 ± 0.54-cm root length, and 6.10 ± 0.31 roots per plantlet. Moreover, this study showed that the growth-stimulating effect of this mechanocomposite treatment on root formation resulted in increased rosette height, leaf number, leaf area, and dry weight of aerial parts. Histological analysis of the leaf blades revealed decreased mesophyll thickness of microshoots treated with the mechanocomposite (up to 88.77 ± 2.95 vs. 111.51 ± 3.56 μm for the control). Morphometric analysis of scanning electron microscopy data showed that mechanocomposite treatments led to increased stomata density and stomata length. These structural changes led to normalization of the water regime and indicated successful acclimatization. The combination of ex vitro rooting and acclimatization reduced the procedure time by 4 wk, and may be used for commercial strawberry micropropagation

Deuterated molecules in regions of high-mass star formation

We present the results of our studies of deuterated molecules (DCN, DNC, DCO+, N2D+ and NH2D) in regions of high-mass star formation, which include a survey of such regions with the 20-m Onsala radio telescope and mapping of several objects in various lines with the 30-m IRAM and 100-m MPIfR radio telescopes. The deuteration degree reaches ∼10−2 in these objects. We discuss its dependencies on the gas temperature and velocity dispersion, as well as spatial distributions of deuterated molecules. We show that the H13CN/HN13C intensity ratio may be a good indicator of the gas kinetic temperature and estimate densities of the investigated objects

Environmental reconstruction inferred from the intestinal contents of the Yamal baby mammoth Lyuba (Mammuthus primigenius Blumenbach, 1799)

The article presents the results of a complex investigation of the intestinal content of the frozen mummy of a baby woolly mammoth (Mammuthus primigenius Blumenbach, 1799) found in 2007 in the Yamal Peninsula (Western Siberia). The mummy belongs to a female mammoth calf approximately 1-1.5 months of age, and it has been named “Lyuba”. Analysis of bone tissue yielded a 14C date of 41,910 (+550/-450) years ago. Analysis of detritus material from the large intestine yielded a 14C date of 41,700 (+700/-550) years ago. These dates practically coincide, thus denoting synchronism of the time of the baby mammoth’s death and the formation of its intestinal contents. This time correspond to the middle part of MIS 3, or the Middle Weichselian Pleniglacial. Pollen, phytolith, plant macrofossil and mineral analyses of the intestinal content were carried out. Reconstruction of the environment where the baby mammoth lived is given based on the intestinal content analyses. The data suggest that the baby mammoth lived in tundra-like landscapes dominated by grass-sedge communities with forbs and Betula nana.