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Polyhydrides are a novel class of superconducting materials with extremely high critical parameters, which is very promising for applications. On the other hand, complete experimental study of the magnetic phase diagram for the best so far known superconductor, lanthanum decahydride LaH$_{10}$, encounters a serious complication because of the large upper critical magnetic field $\textit{H}$$_{C2}$(0), exceeding 120-160 T. Partial replacement of La atoms by magnetic Nd atoms results in a decrease of the upper critical field, which makes it attainable for existing pulse magnets. We found that addition of neodymium leads to significant suppression of superconductivity in LaH$_{10}$: each atomic % of Nd causes decrease in $\textit{T}$$_{C}$ by 10-11 K. Using strong pulsed magnetic fields up to 68 T, we constructed the magnetic phase diagram of the ternary (La,Nd)H$_{10}$ superhydride, which appears to be surprisingly linear with $\textit{H}$$_{C2}$ $\propto$ |$\textit{T}$ - $\textit{T}$$_C$|. The pronounced suppression of superconductivity in LaH$_{10}$ by magnetic Nd atoms and the robustness of $\textit{T}$$_C$ with respect to nonmagnetic impurities (e.g., Y, Al, C) under Anderson's theorem indicate the isotropic ($\textit{s}$-wave) character of conventional electron-phonon pairing in the synthesized superhydrides., Comment: Supporting Information is included

Drastic recircumscription of Pentanema (Asteraceae) has resulted in transfers of many species from Inula, whereas hybrids with binomials have not received new combinations yet. However, names for interspecific hybrids of Inula auct. are in active current use, and a dozen nothospecies are regularly mentioned in floras, checklists, and research papers. I have facilitated 12 new combinations for nothospecies in Pentanema: P. xadriaticum (Borbas) Seregin (P. hirtum x P. spiraeifolium), P. xhaussmannii (Huter) Seregin (P. ensifolium x P. hirtum), P. xhispidum (Schur) Seregin (P. asperum x P. hirtum), P. xhybridum (Baumg.) Seregin (P. ensifolium x P. germanicum), P. xlitorale (Borbas) Seregin (P. ensifolium x P. spiraeifolium), P. xmucheri (Starm.) Seregin (P. salicinum x P. squarrosum), P. xsavii (Beck) Seregin (P. salicinum x P. spiraeifolium), P. xsemiamplexicaule (Reut.) Seregin (P. helveticum x P. salicinum), P. xstrictum (Tausch) Seregin (P. ensifolium x P. salicinum), P. xsuaveolens (Jacq.) Seregin (P. oculus-christi x P. squarrosum), P. xtranssilvanicum (Schur) Seregin (P. asperum x P. germanicum), P. xvrabelyianum (Kern.) Scregin (P. asperum x P. ensifolium). A lectotype is designated for Inula xhausmannii Hutcr in place of the superseded neotype published in 2019. Examples of current use arc given for each hybrid. Availability of the new names will certainly be helpful for wider use and acceptance of Pentanema.

Massive imaging of herbarium collections is performed only in a few countries, leading to disproportions in geographical coverage of the world's flora across virtual herbaria. The Moscow University Herbarium (MW) digitised all Asian collections in 2016-2017 and published them online at https://plant.depo.msu.ru/, including 3283 specimens from Turkey. These collections include important historical gatherings by P.E. Boissier, C. Haussknecht, and T. Kotschy and recent collections by the Moscow University staff members. Currently, MW holds 331 type specimens of 285 taxa described from Anatolia-19 holotypes, 47 isotypes, 48 isolectotypes, and 203 syntypes.

Structural changes in vertebrate bone tissues caused by bone growth or by weightlessness were studied using a combination of X-ray tomography at different wavelengths and X-ray fluorescence analysis., A combination of X-ray tomography at different wavelengths and X-ray fluorescence analysis was applied in the study of two types of bone tissue changes: prolonged presence in microgravity conditions and age-related bone growth. The proximal tail vertebrae of geckos were selected for investigation because they do not bear the supporting load in locomotion, which allows them to be considered as an independent indicator of gravitational influence. For the vertebrae of geckos no significant differences were revealed in the elemental composition of the flight samples and the synchronous control samples. In addition, the gecko bone tissue samples from the jaw apparatus, spine and shoulder girdle were measured. The dynamics of structural changes in the bone tissue growth was studied using samples of a human fetal hand. The hands of human fetuses of 11–15 weeks were studied. Autonomous zones of calcium accumulation were found not only in individual fingers but in each of the investigated phalanges. The results obtained are discussed.

Junin virus (JUNV), a highly pathogenic New World arenavirus, is the causative agent of Argentine hemorrhagic fever (AHF). The live-attenuated Candid #1 (Can) strain currently serves as a vaccine for at-risk populations. We have previously shown that the Can glycoprotein (GPC) gene is the primary gene responsible for attenuation in a guinea pig model of AHF. However, the mechanisms through which the GPC contributes to the attenuation of the Can strain remain unknown. A more complete understanding of the mechanisms underlying the attenuation and immunogenicity of the Can strain will potentially allow for the rational design of additional safe and novel vaccines. Here, we provide a detailed comparison of both RNA and protein expression profiles between both inter- and intra-segment chimeric JUNV recombinant clones expressing combinations of genes from the Can strain and the pathogenic Romero (Rom) strain. The recombinant viruses that express Can GPC, which were shown to be attenuated in guinea pigs, displayed different RNA levels and GPC processing patterns as determined by Northern and Western blot analyses, respectively. Analysis of recombinant viruses containing amino acid substitutions selected at different mouse brain passages during the generation of Can revealed that altered Can GPC processing was primarily due to the T168A substitution within G1, which eliminates an N-linked glycosylation motif. Incorporation of the T168A substitution in the Rom GPC resulted in a Can-like processing pattern of Rom GPC. In addition, JUNV GPCs containing T168A substitution were retained within the endoplasmic reticulum (ER) and displayed significantly lower cell surface expression than wild-type Rom GPC. Interestingly, the reversion A168T in Can GPC significantly increased GPC expression at the cell surface. Our results demonstrate that recombinant JUNV (rJUNV) expressing Can GPC display markedly different protein expression and elevated genomic RNA expression when compared to viruses expressing Rom GPC. Additionally, our findings indicate that the N-linked glycosylation motif at amino acid positions 166–168 is important for trafficking of JUNV GPC to the cell surface, and the elimination of this motif interferes with the GPC release from the ER.

Sennikov, Alexander N., Seregin, Alexey P. (2014): Nomenclatural corrections in vascular plants, 1. Valid publication of Allium savranicum "Besser". Phytotaxa 161 (1): 97-100, DOI: 10.11646/phytotaxa.161.1.5, URL: http://dx.doi.org/10.11646/phytotaxa.161.1.5

Seregin, Alexey P. (2012): Taxonomic circumscription and distribution of a glandular Eurasian entity from the Eragrostis pilosa complex (Poaceae). Phytotaxa 52 (1): 8-20, DOI: 10.11646/phytotaxa.52.1.2, URL: http://biotaxa.org/Phytotaxa/article/view/phytotaxa.52.1.2

Seregin, Alexey P. (2012): Allium tarkhankuticum (Amaryllidaceae), a new species of section Oreiprason endemic to the Crimean steppe, Ukraine. Phytotaxa 42: 9-18, DOI: 10.11646/phytotaxa.42.1.2, URL: http://biotaxa.org/Phytotaxa/article/view/phytotaxa.42.1.2

The arbuscular mycorrhizal (AM) fungi are a globally distributed group of soil organisms that play critical roles in ecosystem function. However, the ecological niches of individual AM fungal taxa are poorly understood. We collected > 300 soil samples from natural ecosystems worldwide and modelled the realised niches of AM fungal virtual taxa (VT; approximately species-level phylogroups). We found that environmental and spatial variables jointly explained VT distribution worldwide, with temperature and pH being the most important abiotic drivers, and spatial effects generally occurring at local to regional scales. While dispersal limitation could explain some variation in VT distribution, VT relative abundance was almost exclusively driven by environmental variables. Several environmental and spatial effects on VT distribution and relative abundance were correlated with phylogeny, indicating that closely related VT exhibit similar niche optima and widths. Major clades within the Glomeraceae exhibited distinct niche optima, Acaulosporaceae generally had niche optima in low pH and low temperature conditions, and Gigasporaceae generally had niche optima in high precipitation conditions. Identification of the realised niche space occupied by individual and phylogenetic groups of soil microbial taxa provides a basis for building detailed hypotheses about how soil communities respond to gradients and manipulation in ecosystems worldwide.

The paper presents new records for 29 vascular plant species from 12 Eurasian countries. Seven taxa (Agave sisalana, Austrocylindropuntia subulata, Lagurus ovatus subsp. nanus, Opuntia stricta, Orobanche serbica, Oxalis articulata, Vitis × instabilis) are reported from Albania, one (Allium carinatum) from the Europaean part of Russia, six (Dipsacus fullonum, Gagea shmakoviana, Mentha × dalmatica, Thymus indigirkensis, Thymus sergievskajae, Viola × sukaczewii) from the Asian part of Russia, two (Agrostis sozanensis, Poa mustangensis) from China, two (Carex muskingumensis, Sedum rubens) from Poland, two (Crataegus macrocarpa, Dactylorhiza lapponica) from Romania, two (Oxygraphis delavayi, Ranunculus eryuanensis) from Nepal, two (Erigeron bonariensis, Ophioglossum vulgatum) from Tajikistan, one (Ranunculus olgae) from Kazakhstan, one (Najas guadelupensis) from Hungary, one (Orobanche bartlingii) from Armenia, one (Crataegus petrodavisii) from Azerbaijan and one (Amaranthus powellii) from Georgia. For each species, synonyms, general distribution, habitat preferences, taxonomy with remarks on recognition, and differentiation the species from the most similar taxa occurring in a given country, as well as a list of recorded localities (often far from the previously known areas) are presented.