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Aliterella vladivostokensis Sh. R. Abdullin, A. Yu. Nikulin, V. B. Bagmet et V. Yu. Nikulin 2021, sp. nov.
No full textAliterella vladivostokensis Sh.R. Abdullin, A.Yu. Nikulin, V.B. Bagmet et V.Yu. Nikulin sp. nov. (Fig. 1) Description: —Cells solitary, more commonly irregular or in rounded colonies with many cells (up to 32–64 or more), usually aggregated irregularly, extended (Fig. 1 A–C). Mucilage unstratified, colorless and firm, surrounding cells and colonies. Cells cylindrical 1.6–6.87 μm long, 1.17–5.85 μm wide, 1 to 1.75 × longer than wide (mean, 1.28 ×) (Fig. 1 C–D). Cells easily squeezing from colonies with pressure (Fig. 1 C). The chromatoplasm and centroplasm usually recognizable with light microscopy (Fig. 1 C–D). Cell contents blue-green, slightly granulated, or sometimes homogeneous. Reproduction by simple binary cell division in three or more planes. Holotype: —The dried biomass of authentic strain was deposited to the Herbarium of the Federal Scientific Center of East Asia Terrestrial Biodiversity, Russia (exsiccatum number VLA-CA-1212) as a holotype. Type locality: — RUSSIA. Primorsky Territory, Vladivostok, 43°10’21.4” N, 131°56’10.9” E, collected by Shamil R. Abdullin on August 7, 2018. The authentic strain VCA-43 (Vl15-3) is available in the culture collection of the Laboratory of Botany, Federal Scientific Center of East Asia Terrestrial Biodiversity, Russia. Habitat: —This cyanobacteria occurred in aerophytic habitat (on the concrete fence). Etymology: —The species epithet ‘ vladivostokensis ’ is derived from the type locality Vladivostok City. Molecular phylogeny and sequence analyses: —Results of the BLAST searches showed that the sequence of the 16S rRNA gene and internal transcribed spacer (ITS) region (1800 bp) in our strain was highly similar to those in other species of Aliterella, several uncultured bacterial clones, and Synechocystis sp. PCC 7509 (> 94.5%). When only the ITS region was compared, the similarity to Aliterella spp. was just above 85%. Such relatively low similarity percentages suggested that we were likely dealing with a new species. Phylogenetic analyses (ML and BI) clearly indicated that A. vladivostokensis was a member of the strongly supported (99/1.00; BP/PP; Fig. 2) Aliterella generic clade. Branching pattern between the clade members remained largely unresolved (Fig. 2). We observed the highest 16S rRNA sequence similarities based on p -distance analysis between our isolate and an uncultured bacterial clone (DQ532167) isolated from clean spacecraft assembly rooms where spacecrafts are assembled (99.5%; Table 1). A. antarctica (KU291459) and A. shaanxiensis (MH023997) were the most similar to each other among described Aliterella species, (99.1%). Since no ITS sequences were available for the uncultured bacterial clones resolved as members of the Aliterella clade (5 accessions), we only compared the percentage of sequence dissimilarity between aligned 16S–23S ITS regions for the described taxa and Synechocystis sp. PCC 7509 (6 accessions). The dissimilarity varied from 6.4% to 17.5% (11.6%–17.5% between A. vladivostokensis and the other species; Table 2). Comparison of ITS secondary structures of the D1–D1′ and Box-B helices showed that they have similar patterns of bulges and terminal loops (Fig. 3, 4). The D1–D1′ helix was almost invariant in length (65–67 bp) and structure with 42 conserved sites among Aliterella species (Fig. 3). In Synechocystis sp. PCC 7509 the helix was shorter (57 bp) due to the deletion in the terminal loop (Fig. 3). The basal part of the D1–D1′ helix consisted of a conservative 4-bp double-stranded region followed by the internal (bilateral) loop (positions 5–6 and from 55–57 to 61–63 in different Aliterella species; 5–6 and 47–53 in Synechocystis sp. PCC 7509) and side loop with a single unpaired base (position 51–52, position 43 for Synechocystis sp. PCC 7509). Substitutions in the bilateral loop (base change U → C at position 57) and in the side loop (A → C at position 51) differentiated A. vladivostokensis. The terminal loop of the helix consisted of five bp and also harbored a unique marker mutation for the new species (A → C at position 29). Most species had two internal loops in the central part of D1–D1′ helix with the exception of A. shaanxiensis, which had three loops and Synechocystis sp. PCC 7509 with the one loop. We found one compensatory base change (CBC) and five hemi-compensatory base changes (hCBCs) in our secondary structure models. While CBC (A-U → G-C) was shared between A. vladivostokensis and A. antarctica (at positions 19–42 in both cases), the hCBCs were attributed to A. atlantica (C-G → U-G, at position 22), A. antarctica (two substitutions C-G → U-G at positions 20 and 27), A. chasmolithica (G-C → G-U, at position 33; Fig. 3), and Synechocystis sp. PCC 7509 (C-G → U-G at position 13). The Box-B helix was more variable in both primary and secondary structure (53–62 bp, 29 conservative sites); therefore, homologous nucleotides were difficult to identify in some cases (Fig. 4). The middle part of the Box-B helix had two (A. atlantica) to four (A. vladivostokensis) mostly bilateral internal loops. Point mutations, mostly found in single stranded domains, and indels frequent in the basal part of the Box-B altered the bulges location between species. A base substitution G → U at position 11 in the Box-B disrupted nucleotides pairing that led to an additional internal loop formation in A. vladivostokensis sequence (Fig. 4). The Box-B helix in Synechocystis sp. PCC 7509 differed from those in other species in lacking conservative motive at the base of the helix and shorter terminal loop (5 vs. 7–9 bases; Fig. 4). We found one CBC in Synechocystis sp. PCC 7509 (A-U → U-G, at positions 3 and 29) and one hCBC in A. chasmolithica (A-U → G-U, at position 3).Published as part of Abdullin, Shamil R., Nikulin, Arthur Yu., Bagmet, Veronika B., Nikulin, Vyacheslav Yu. & Gontcharov, Andrey A., 2021, New cyanobacterium Aliterella vladivostokensis sp. nov. (Aliterellaceae, Chroococcidiopsidales), isolated from temperate monsoon climate zone (Vladivostok, Russia), pp. 221-233 in Phytotaxa 527 (3) on pages 223-227, DOI: 10.11646/phytotaxa.527.3.7, http://zenodo.org/record/575142
Reply to: “Levodopa‐Induced Dyskinesia Is Mediated by Cortical Gamma Oscillations in Experimental Parkinsonism”
No full textOn group fields of arithmetic hyperbolic reflection groups: III
No full textThe paper continues from the work of Nikulin. Using our methods of 1980 and 1981, we define some explicit finite sets of number fields containing all ground fields of arithmetic hyperbolic reflection groups in dimensions at least 3, and we give good upper bounds for their degrees (over Q). This extends the earlier results of Nikulin for dimensions at least 4. This finally delivers a possibility, in principle, of effective finite classification of maximal arithmetic hyperbolic reflection groups (more generally, of reflective hyperbolic lattices) in all dimensions. Our results also give another proof of finiteness in dimension 3. In fact, using our methods, we show that finiteness in dimension 3 follows from finiteness in dimension 2
author-bios-SRD-19-0063.R1 – Supplemental material for The Network Structure of Police Misconduct
No full textSupplemental material, author-bios-SRD-19-0063.R1 for The Network Structure of Police Misconduct by George Wood, Daria Roithmayr and Andrew V. Papachristos in Socius</p
Early Detection of Epidemics as a Sequential Change-Point Problem
No full textPublished in "Longevity, Aging and Degradation Models in Reliability, Public Health, Medicine and Biology", edited by V. Antonov, C. Huber, M. Nikulin, and V. Polischook; volume 2, St. Petersburg, 2004; pp. 31-4
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
State-dependent effects of transcranial oscillatory currents on the motor system during action observation
Get PDFWe applied transcranial alternating current stimulation (tACS) to the primary motor cortex (M1) at different frequencies during an index–thumb pinch-grip observation task. To estimate changes in the corticospinal output, we used the size of motor evoked potentials (MEPs) obtained by transcranial magnetic stimulation (TMS) of M1 using an online MRI-guided simultaneous TMS-tACS approach. The results of the beta-tACS confirm a non-selective increase in corticospinal excitability in subjects at rest; an increase was observed for both of the tested hand muscles, the first dorsal interosseous (FDI) and the abductor digiti minimi (ADM). However, during action observation of the pinch-grip movement, the increase of corticospinal excitability was only observed for the prime mover FDI muscle and took place during alpha-tACS, while gamma-tACS affected both the FDI and control muscle (ADM) responses. These phenomena likely reflect the hypothesis that the mu and gamma rhythms specifically index the downstream modulation of primary sensorimotor areas by engaging mirror neuron activity. The current neuromodulation approach confirms that tACS can be used to induce neurophysiologically detectable state-dependent enhancement effects, even in complex motor-cognitive tasks. © 2019, The Author(s)
Statistical analysis of the generalized additive semiparametric survival model with random covariate
Get PDFGeneralizations of the additive hazards model are considered. Estimates of the regression parameters and baseline function are proposed, when covariates are random. The asymptotic properties of estimators are considered
Statistical analysis of the generalized additive semiparametric survival model with random covariate
No full textGeneralizations of the additive hazards model are considered. Estimates of the regression parameters and baseline function are proposed, when covariates are random. The asymptotic properties of estimators are considered
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