114,664 research outputs found
Mallomonas spinosa Gusev 2012, sp. nov.
No full text<i>Mallomonas spinosa</i> Gusev, <i>sp. nov.</i> (Figs 2–11) <p>Cells ellipsoidal, approximately 20 × 11 µm, covered by scales with spines (Fig. 2). Apical scales lack spines (Fig. 4). Body scales oval, 4.5–5.6 × 2.7–3.6 µm. Shield with densely and regularly spaced papillae (Figs. 6–11). V-rib conspicuous, acute to slightly rounded. Distal ends of arms of V-rib curve and become continuous with anterior submarginal ribs. Anterior submarginal rib forms a prominent asymmetrically placed stout spine with four edges (Fig. 7). Anterior flange with a row of papillae (Fig. 8). Posterior flange smooth with depression containing pores on the base plate (Figs. 5–11). Posterior rim wide and smooth in SEM view. Bristles unknown. Cysts not observed.</p> <p> <b>Type:</b> — VIETNAM. Dong Nai Province: unnamed temporary forest pool in Cat Tien National Park, 11°24’26” N, 107°24’48” E, 23 November 2010, <i>E.S. Gusev s.n.</i> SEM stub CT40/2010 (holotype IBIW!, see Fig. 2), sample CT40 23.11.2010, in collection E.S. Gusev.</p> <p> <b>Distribution and habitat:—</b> This species was found in the type locality and two other water bodies in Khanh Hoa province in Vietnam.</p> <p> <b>Etymology:—</b> The epithet “spinosa” refers to the whole cell being covered by scales with stout spines.</p>Published as part of <i>Gusev, Evgeniy S., 2012, A new species of the genus Mallomonas (Synurophyceae), Mallomonas spinosa sp. nov., from Vietnam, pp. 1-5 in Phytotaxa 66 (1)</i> on pages 2-3, DOI: 10.11646/phytotaxa.66.1.1, <a href="http://zenodo.org/record/5065820">http://zenodo.org/record/5065820</a>
Mallomonas kuzminii E. S. Gusev & Kulikovskiy 2013, sp. nov.
No full textMallomonas kuzminii E.S. Gusev & Kulikovskiy, sp. nov. (Figs. 2–11) Cells dimensions unknown. Scales tripartite, 3.1–6.4 × 1.9–4.0 µm, with or without dome. Body scales oblong-oval or asymmetric with a narrowed and tapered distal part. Caudal scales with a short spine (Figs. 6, 12, 15). Dome with ribs (Figs. 2–3, 7–8) and surrounded by an extension of the anterior rib (Fig. 8). V-rib acute or rounded, hooded (Figs. 7–11), continuous with the anterior submarginal rib. Posterior flange and shield with pores and without a secondary layer. Pores can be evenly spaced on all the surface (Figs. 2, 6, 7) or irregularly distributed on the posterior flange and shield (Figs. 3- 5, 8-11). A patch of small pores is present in the angle of the V-rib (Figs. 2, 5–6). The proximal part of the scale is surrounded by a thin rim. Bristles dentate, curved, with pointed tips, 8–14 µm long (Figs. 14, 17). Cyst ca. 18 µm in diameter. Type: — RUSSIA. Republic of Buryatia: Lake Frolikha, 55° 26’ 15” N, 110° 1’ 16” E, E.S. Gusev s.n. SEM stub 75/1 (holotype IBIW!, Fig. 3), sample “Baikal 75”, 26-7-2012, in collection E.S. Gusev. Distribution:— This species was only found in the type locality. Etymology:— This species dedicated to G.V. Kuzmin, well-known specialist on algae, one of the first investigators of scaled chrysophytes in East Siberia.Published as part of Gusev, Evgeniy S. & Kulikovskiy, Maxim S., 2013, A new species of the genus Mallomonas (Chrysophyceae: Synurales), Mallomonas kuzminii sp. nov., from lake Frolikha (Russia, Baikal region), pp. 66-70 in Phytotaxa 155 (1) on page 67, DOI: 10.11646/phytotaxa.155.1.6, http://zenodo.org/record/510095
On Synchronizing Colorings and the Eigenvectors of Digraphs
No full textAn automaton is synchronizing if there exists a word that sends all states of the automaton to a single state. A coloring of a digraph with a fixed out-degree k is a distribution of k labels over the edges resulting in a deterministic finite automaton. The famous road coloring theorem states that every primitive digraph has a synchronizing coloring. We study recent conjectures claiming that the number of synchronizing colorings is large in the worst and average cases.
Our approach is based on the spectral properties of the adjacency matrix A(G) of a digraph G. Namely, we study the relation between the number of synchronizing colorings of G and the structure of the dominant eigenvector v of A(G). We show that a vector v has no partition of coordinates into blocks of equal sum if and only if all colorings of the digraphs associated with v are synchronizing. Furthermore, if for each b there exists at most one partition of the coordinates of v into blocks summing up to b, and the total number of partitions is equal to s, then the fraction of synchronizing colorings among all colorings of G is at least (k-s)/k. We also give a combinatorial interpretation of some known results concerning an upper bound on the minimal length of synchronizing words in terms of v
Mallomonas acidophila Gusev & Shkurina & Huan 2023
No full text<i>Mallomonas acidophila</i> Gusev & Shkurina (Figures 2–22) <p>Cell dimensions unknown. Scales are tripartite, oval, 4.3–5.6 × 2.4–3.5 μm, with a dome, a V-rib, anterior submarginal ribs, a shield, anterior and posterior flanges, and a posterior rim. The base plate is devoid of pores. The dome is recessed from the distal margin, shallow, elongated or narrowly elliptical, sometimes curved. The dome can be placed perpendicular to the longitudinal axis of the scale or at an angle to this axis. It is covered with papillae. The shield is ornamented with numerous unevenly distributed papillae. The V-rib is rounded, with a broad and U-shaped base, slightly hooded, with arms that are continuous with the anterior submarginal ribs. The anterior submarginal ribs are of equal length if the dome is perpendicular to the longitudinal axis or unequal if the dome is located at an angle to the longitudinal axis. The anterior flanges are narrow. The posterior rim is narrow and encircles one-third to one-half of the scale perimeter. The posterior flange is wide and smooth. It lacks a secondary siliceous layer in a narrow area along the posterior rim and is strongly thickened in the area adjacent to the V-rib. Bristles are 2.4–7.2 μm long, straight, with a hook-shaped flattened foot, turned at an angle of approximately 45 degrees or less relative to the shaft, gutter-shaped bristle shaft, and a flattened and bifurcated apical tip with a wide, rounded middle part. Cysts are unknown.</p> <p> <b>Holotype (</b> designated here <b>)</b>:— Portion of a single gathering of cells on SEM stub number TTH55 deposited at the Herbarium of the Papanin Institute for Biology of Inland Waters RAS, Borok (IBIW). Material from unnamed reservoir in Thua Thien Hue Province, Vietnam. Sample collected 28 October 2022 by E. Gusev. Figure 3 is a representative scale from the type specimen.</p> <p>Type locality:— Vietnam: unnamed swamp water body in Thua Thien Hue Province, Phong Điễn District, Latitude / Longitude: N16°39.777’ E107°21.905’.</p> <p> <b>Etymology</b>:—The epithet “acidophila” refers to the fact that this species is found at low pH values.</p> <p> <b>Distribution:</b> —To date, <i>M</i>. <i>acidophila</i> has been observed in two neighbouring localities in Vietnam. In addition to the type locality, it has been found in another unnamed water body (Latitude/Longitude: N16°39.694’ E107°21.746’).</p> <p> <b>Observations:</b> — <i>Mallomonas acidophila</i> was found in acidic conditions (pH 5.0–5.2), with low specific conductance values ranged from 17 to 18 μS cm-1, temperature 26 ºC, total phosphorus concentrations 68–133 μL-1, Kjeldahl nitrogen concentrations 406–508 μL-1.</p>Published as part of <i>Gusev, Evgeniy, Shkurina, Nataliya & Huan, Phan Trong, 2023, Mallomonas acidophila sp. nov. (Synurales, Chrysophyceae) - a new species from the tropics with morphological features of fossil taxa, pp. 157-166 in Phytotaxa 620 (2)</i> on page 159, DOI: 10.11646/phytotaxa.620.2.3, <a href="http://zenodo.org/record/10022374">http://zenodo.org/record/10022374</a>
Non-uniqueness and prescribed energy for the continuity equation
No full textIn this note, we provide new non-uniqueness examples for the continuity equation by constructing infinitely many weak solutions with prescribed energy
Mallomonas voloshkoae Gusev & Němcová & Kulikovskiy 2022, sp. nov.
No full text<i>Mallomonas voloshkoae sp. nov.</i> Gusev, Němcová & Kulikovskiy (Figs. 2–18) <p> <b>Description</b>: Scales are 3.4–4.5 × 1.7–2.4 μm (up to 2.6 μm with winged flanges), oval to obovate with lateral incurvings. Scales possess a posterior rim, a V-rib, anterior ribs and flanges, and a dome. The dome is subcircular and smooth. The shield is marked with four to six regularly spaced transverse ribs. A group of numerous pores, usually more than 20, is located at the angle of the V-rib in the posterior part of the shield. Anterior flanges are wide, in the form of wing-like extensions, with three to seven closely spaced struts. Anterior flanges surround the dome. The anterior submarginal ribs are well developed. The V-rib on the scales is acutely angled, slightly hooded, and continues on wing-like extensions. The posterior rim bears internal struts but is smooth on the surface. The posterior flange bears approximately 14–18 struts and scattered base-plate pores, sometimes organised to form a row (Fig. 6). Bristles are 4.5–6.2 μm in length, slightly curved. The distal end of the bristle is widened. The tip is bifurcated with unequal diverging branches. One branch is short and sharp, whereas the other is wide with an acute tip and flat dorsal side (Figs. 10–14). Cysts were not observed.</p> <p> <b>Holotype specimen</b>: Portion of a single gathering of cells on SEM stub No. B137 deposited at the Herbarium, Papanin Institute for Biology of Inland Waters RAS, Borok (IBIW). Material from an unnamed lake in the Barguzin Mountains, Republic of Buryatia, Russia, collected by E.S. Gusev and M.S. Kulikovskiy on 18 July 2014. Figure 2 illustrates a representative scale from the holotype specimen. <b>Type Locality</b>: Unnamed lake 1 in Barguzin Mountains, Republic of Buryatia, Russia. Latitude/Longitude: N55° 26.250’ E110° 16.363’.</p> <p> <b>Epithet</b>: The species is named in honour of Lyudmila Voloshko, a well-known specialist in chrysophyte algae.</p> <p> <b>Distribution</b>: In addition to the type locality, this species was observed in other lakes of the Transbaikal area (Table 1). <i>Mallomonas voloshkoae</i> was found in acidic to slightly acidic conditions (pH from 5.2 to 6.5) with a specific conductance ranging from 2 to 14 µS cm-1 and a temperature of 12–20°C (Table 1).</p>Published as part of <i>Gusev, Evgeniy, Němcová, Yvonne & Kulikovskiy, Maxim, 2022, Mallomonas voloshkoae sp. nov. (Synurales, Chrysophyceae) and distribution of M. pechlaneri in mountain lakes of Siberia, pp. 221-229 in Phytotaxa 530 (2)</i> on pages 224-226, DOI: 10.11646/phytotaxa.530.2.9, <a href="http://zenodo.org/record/5832781">http://zenodo.org/record/5832781</a>
Neproletarskie partii Rossii v trech revoljucijach. Sbornik statej. Otv. red. Kirill Vladimirovič Gusev
No full textHäfner L. Neproletarskie partii Rossii v trech revoljucijach. Sbornik statej. Otv. red. Kirill Vladimirovič Gusev. Jahrbücher für Geschichte Osteuropas. 1991;39(3):431-433
Erratum to: Endomorphisms of the lattice of epigroup varieties (Semigroup Forum, (2016), 93, 3, (554-574), 10.1007/s00233-016-9825-6)
No full textThe correct authors’ names for this article are S. V. Gusev and B. M. Vernikov. © 2016, Springer Science+Business Media New York
Mallomonas pseudocorymbosa Gusev, Martynenko & Shkurina 2023, sp. nov.
No full text<i>Mallomonas pseudocorymbosa</i> Gusev, Martynenko & Shkurina <i>sp. nov.</i> (Figure 2). <p> <b>Diagnosis:</b> Scales are oval, tripartite, 4.8–5.9 × 3.3–4.3 µm in size, with or without a dome. The dome is large, rounded, oval or asymmetrical. The V-rib is acute, slightly hooded and its arms continuous with the anterior submarginal ribs. Anterior submarginal ribs are well developed. The anterior flange is wide, especially on the domeless scales, with a row of base plate pores at each side. The posterior flange is wide, with numerous base plate pores distributed on the surface. The shield and posterior flange have a secondary siliceous layer forming circular or elongated oval meshes unevenly distributed on the surface often with areas without development of the secondary layer. Numerous pores are placed on the basal plate. The posterior upturned rim is narrow, with inner struts visible only on TEM images, encircles less than a half of the scale perimeter. Bristles are 13–25 μm long, curved and serrated at the distal half. Shorter bristles have a bifurcated tip with a long terminal spine, and longer bristles have a prolonged thread-like terminal part. Cysts unknown.</p> <p> <i>Holotype (here designated):</i> Portion of a single gathering of cells on SEM stub No. CD8 deposited at the Herbarium, Papanin Institute for Biology of Inland Waters RAS, Borok (IBIW). Material from Ahn Hai Lake, Côn SƠn Island, Bà Rịa-Vũng Tàu Province, Vietnam. Figure 2C illustrates a representative scale from the holotype specimen.</p> <p> <i>Type Locality:</i> Ahn Hai Lake, Côn SƠn Island, Bà Rịa-Vũng Tàu Province, Vietnam. Latitude / Longitude: 8° 40.645’ N 106° 35.867’ E. At the time of collection, the pH was 6.5, temperature 30 °C, and specific conductance 201 µS cm-1. Material was collected by E.S. Gusev and Nguyen-Ngoc Lam on 3 May 2015.</p> <p> <i>Etymology:</i> The species name is derived from the fact that its scales resemble, and could be confused with, those of <i>Mallomonas corymbosa</i>.</p> <p> <i>Distribution:</i> This species has been observed in 17 localities in 13 provinces of Vietnam (Table 1). Scales of this species were also observed in Bangladesh (Takahashi & Hayakawa 1979), China (Wei &Yuan 2001, 2013; Wei <i>et al</i>. 2014), Brazil (Franceschini & Couté 1991)and South Africa (Janse van Vuuren <i>et al</i>. 2022). <i>Mallomonas pseudocorymbosa</i> was found at wide ranges of environmental parameters: pH from 6.1 to 8.6, specific conductance from 62 to 2370 µS cm-1, chlorophyll <i>a</i> values from 5 to 76 µg l –1, and temperature 17–39 ºC (Table 1).</p>Published as part of <i>Gusev, Evgeniy, Martynenko, Nikita, Shkurina, Nataliya & Dien, Tran Duc, 2023, Description of a new species of the genus Mallomonas from section Mallomonas (Synurales, Chrysophyceae) in the tropics, pp. 59-68 in Phytotaxa 618 (1)</i> on page 62, DOI: 10.11646/phytotaxa.618.1.5, <a href="http://zenodo.org/record/8389917">http://zenodo.org/record/8389917</a>
Cryptomonas uralensis Martynenko, Gusev, Kulizin & Guseva 2020, sp. nov.
No full textCryptomonas uralensis Martynenko, Gusev, Kulizin & Guseva sp. nov. Figs 2–12 Diagnosis Cells (absolute minimal and maximal values of strain UR168) 15–26 µm long, 8–17 µm wide, 8–12 µm thick. Cells more or less flattened in dorso-ventral plane, in ventral view elliptical to ovoid. In lateral view with oblique or rounded apex and rounded antapex. One plastid with two to four pyrenoids. Species differs from other species of the genus by the order of nucleotides in nuclear ITS2, LSU and SSU rDNA gene sequences. Etymology The species name derived from “Ural”, the region from which this taxon was described. Type material Holotype RUSSIA • Solikamsk town, water-body in the Usolka River flood plain; 59°38′59″ N, 56°44′57″ E; 2014; collected by N.A. Martynenko; strain UR168; GenBank MN509781, MN509779; MHA [Cryptomonas uralensis Russia Martynenko 20-2 MHA, strain UR168]. The holotype is a large drop of unfixed dried cells of the strain UR168 (= IPPAS H-2046) on water colour paper (hic designatus), deposited at MHA (Herbarium, Main Botanical Garden, Botanicheskaya Str. 4, Moscow, 127276, Russia) under the designation Cryptomonas uralensis Russia Martynenko 20-2 MHA, strain UR168. Representative living strain and DNA sample are kept at IPPAS. Representative DNA sequences GenBank accession numbers MN 509781 (nuclear ITS 2 and partial nuclear LSU rDNA), and MN 509779 (nuclear SSU rDNA). Authentic strain UR168 (= IPPAS H-2046). Type locality A water-body in the Usolka River flood plain, Solikamsk town, Russia. Latitude/Longitude 59°38′59″ N, 56°44′57″ E, collected by N.A. Martynenko in 2014. Other representative culture UR167, GenBank accession numbers MN 509780 (nuclear ITS 2 and partial nuclear LSU rDNA), and MN 509778 (nuclear SSU rDNA). Geographical distribution To date, Cryptomonas uralensis sp. nov. has only been observed at the type locality. At the time of collection, the pH was 6.5, temperature 18°C.Published as part of Martynenko, Nikita A., Gusev, Evgeniy S., Kulizin, Pavel V., Guseva, Elena E., McCartney, Kevin & Kulikovskiy, Maxim S., 2020, A new species of Cryptomonas (Cryptophyceae) from the Western Urals (Russia), pp. 1-12 in European Journal of Taxonomy 649 on page 5, DOI: 10.5852/ejt.2020.649, http://zenodo.org/record/383610
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