129,717 research outputs found
Virtual crystals and Nakajima monomials
No full textAn explicit description of the virtualization map for the (modified) Nakajima monomial model for crystals is given. We give an explicit description of the Lusztig data for modified Nakajima monomials in type A(n)
Cobitis striata subsp. hakataensis Nakajima 2012, subsp. nov.
No full text<i>Cobitis striata hakataensis</i> Nakajima, subsp. nov. <p>(Figs. 3C, 4E, F, 5C, 6C)</p> <p> Hakata form of <i>Cobitis striata</i> (middle race): Nakajima <i>et al.</i> 2008: 13, fig. 2G; Hakata form of middle race of <i>Cobitis striata</i> complex: Kitagawa <i>et al.</i> 2009: 12, fig. 2E, F; <i>Cobitis</i> sp. 3 subsp. 3: Nakajima <i>et al.</i> 2012: 92, fig. 3c.</p> <p> <b>Holotype.</b> TKPM-P17342, male, 58.0 mm SL, Japan: Tatara River, Kasuya, Fukuoka Pref., Kyushu, 12. XII. 2010, J. Nakajima.</p> <p> <b>Paratypes.</b> JNC005, 1 male, 54.4 mm SL, same data as holotype; JNC041, 1 male, 60.4 mm SL, Tatara R., Kasuya, Fukuoka Pref., Kyushu, 23. V. 2005, J. Nakajima; KPM-NI29504, male, 55.0 mm SL, Tatara R., Kasuya, Fukuoka Pref., Kyushu, 18. V. 2008, J. Nakajima; MPM-FI1502, 1 male, 48.8 mm SL, same data; FKUN33756, 1 female, 87.4 mm SL, Naka R., Minami-ku, Fukuoka, Fukuoka Pref., Kyushu, 20. IV. 2005, J. Nakajima; JNC006, 1 male, 59.1 mm SL, Muromi R., Nishi-ku, Fukuoka, Fukuoka Pref., Kyushu, 13. V. 2010. E. Miyamura.</p> <p> <b>Non-type specimens.</b> 1 male and 2 females, 56.4–63.4 mm SL, same data as holotype; 1 male and 2 females, 64.0– 69.7 mm SL, Muromi R., Nishi-ku, Fukuoka, Fukuoka Pref., Kyushu, 5. VI. 2006, J. Nakajima; 2 males, 65.0, 65.7 mm SL, Tatara R., Kasuya, Fukuoka Pref., Kyushu, 23. V. 2005, J. Nakajima; 1 male and 1 female, 52.6, 55.5 mm SL, Tatara R., Kasuya, Fukuoka Pref., Kyushu, 18. V. 2008, J. Nakajima.</p> <p> <b>Diagnosis.</b> This subspecies is distinguishable from other Japanese striated spined loaches by the following characteristics: body size moderate, the mature size about 50–60 mm SL in males, 55–80 mm SL in females; lamina circularis at the base of the pectoral fin of adult male simple roundish plate, the upper segments of the first branched soft ray narrow and weak (Fig. 6C); PMN commonly 13; line L3 formed by incomplete longitudinal line, reaching to caudal base; line L4 formed by longitudinal jagged weblike line, reaching to postanal body, broader than L 3 in male of non-spawning season; line L5 organized in 11–14 roundish or ovoid blotches in non-spawning season; caudal fin and dorsal fin with 3–4 arcuate bars; upper spot at the caudal base jet-black comparable in size to eye diameter; lower spot at caudal base faint or missing; egg yolk diameter approximately 1.0mm; karyotype diploid.</p> <p> <b>Description.</b> Lateral view in Figure 3C illustrate body shape, form and position of fins. Morphometric and meristic data for 11 males and 5 females are summarized in Table 2. Dorsal-fin rays iii, 7; anal-fin rays iii, 5; pectoral-fin rays i, 7–8; pelvic-fin rays ii, 6; caudal-fin rays 8+8. Body elongate, laterally compressed. Head and snout elongated. Interorbital space narrow, convex. Caudal peduncle relatively compressed. Mouth small, inferior, arched with fleshy lips; lower lip divided with two well-developed lobes; upper lip with transverse wrinkles on surface. Barbels, 3 pairs, first on rostora, second on maxillae, third on maxillomandibula; each barbel well developed, length of maxillary barbel same as eye diameter; length of rostral and mandibular barbels shorter than that of maxillary barbel. Lateral line short, reaching the central region between the pectoral-fin base and the tip of the fin. PMN commonly 13 (range, 13–14). Very small cycloid scales on the trunk. Lamina circularis at the base of the pectoral fin of adult male simple roundish plate (Fig. 6C). The first branched soft ray of pectoral fin longer than the others; pectoral fin of the male relatively longer than that of the female. The upper segments of the first branched soft ray of pectoral fin narrow and weak. Dorsal-fin base equidistant from the base of the caudal fin and the tip of the snout. Pelvic-fin origin below first or second branched dorsal-fin ray. Anal fin not reaching caudal-fin base. Margin of anal and dorsal fins slightly roundish. Caudal fin slightly roundish. Largest recorded specimens: 65.7 mm SL male, 69.7 mm SL female.</p> <p> <b>Coloration.</b> <i>Male in the non-spawning season</i> (Figs. 3C, 4E). Body yellowish white with dark brown pigmentation in fresh specimens. Clear streak running from the tip of snout to the occiput, crossing to the eye. Upper part of head, opercle and snout covered with oval or amorphous shape spots. Body pigmentation organized in one middorsal and four lateral zones. Line L1 consisting of a series of 14–16, saddles or oval-shaped blotches, irregularly chained to each other. Line L2 formed by longitudinal jagged line, reaching to middorsal region, often fused with L1. Line L3 formed by incomplete longitudinal line, reaching to caudal base. Line L4 formed by longitudinal jagged weblike line, reaching to postanal body, broader than L3. Line L5 organized in 11–14 blotches from upper part of the pectoral fin to the caudal-fin base; blotches roundish or ovoid. Caudal fin and dorsal fin with 3–4 arcuate bars. Anal fin pigmented along the fin rays. Upper spot at the caudal base jet-black comparable in size to eye diameter, lower spot at the caudal base faint or missing.</p> <p> <i>Male in the spawning season</i> (Fig. 4F). Line L4 not visible or formed by faint longitudinal line, present only in anterior half of body. Lines L3 and L5 well developed with broad stripes from the upper part of the pectoral-fin base to the caudal-fin base.</p> <p> <i>Female</i> (Fig. 5C). Appearance similar to males in the non-spawning season, but number of blotches of line L5 tends to be more than in the male, line L5 of female organized in 11–17 blotches.</p> <p> <b>Sexual dimorphism.</b> Males have roundish lamina circularis at the base of the pectoral fin, but females do not. Generally, the body size of females is larger than that of males.</p> <p> <b>Egg diameter.</b> 0.98 ± 0.05 mm (females, N = 3; collected from the Tatara River system, Fukuoka Prefecture).</p> <p> <b>Karyotype.</b> Diploid (Kitagawa <i>et al.</i> 2009).</p> <p> <b>Distribution.</b> Rivers flowing into Hakata Bay, northern Kyushu: Fukuoka Prefecture (Nakajima <i>et al.</i> 2008).</p> <p> <b>Habitat and biology.</b> This species inhabits sandy-mud bottoms of the middle and lower reach of rivers. Life histories are unknown.</p> <p> <b>Etymology.</b> The subspecific name is derived from the popular common name of the Fukuoka City area in which the type locality is situated.</p> <p> <b>Remarks.</b> The genetic features have been reported by Kitagawa <i>et al.</i> (2009).</p> <p> <b>Japanese name.</b> Hakata-suji-shima-dojyô.</p>Published as part of <i>Nakajima, Jun, 2012, Taxonomic study of the Cobitis striata complex (Cypriniformes, Cobitidae) in Japan, pp. 103-130 in Zootaxa 3586</i> on pages 115-11
Hikita-nakajima conjecture for the Gieseker variety
No full textLet M0 be an affine Nakajima quiver variety, and let M be the corresponding BFN Coulomb branch. Assume that M0 can be resolved by the (smooth) Nakajima quiver variety M. The Hikita-Nakajima conjecture claims that there should be an isomorphism of (graded) algebras H∗
S (M, C) C[MC× s ], where S M0 is a torus acting on M0 preserving the Poisson structure, Ms is the (Poisson) deformation of M over s = Lie S, C× is a generic one-dimensional torus acting on M, and C[MC× s ] is the algebra of schematic C×-fixed points of Ms. We prove the Hikita-Nakajima conjecture forM = M(n,r) Gieseker variety (ADHM space). We produce the isomorphism explicitly on generators. We also describe the Hikita-Nakajima isomorphism above using the realization of Ms as the spectrum of the center of the rational Cherednik algebra corresponding to Sn (Z/rZ)n and identify all the algebras that appear in the isomorphism with the center of the degenerate cyclotomic Hecke algebra (generalizing
some results of Shan, Varagnolo, and Vasserot)
Certain Cases of Hikita-Nakajima conjecture
No full textLet be an affine Nakajima quiver variety, and is the corresponding BFN Coulomb branch. Assume that can be resolved by the (smooth) Nakajima quiver variety . The Hikita-Nakajima conjecture claims that there should be an isomorphism of (graded) algebras , where is a torus acting on preserving the Poisson structure, is the (Poisson) deformation of over \mathfrak{s}=\on{Lie}S, is a generic one-dimensional torus acting on , and is the algebra of schematic -fixed points of . In this thesis we prove the Hikita-Nakajima conjecture for \mathfrak{M}= \widetilde{\C^2/ \Gamma} (Kleinian singularities) and Gieseker variety ( space). In the latter case we produce the isomorphism explicitly on generators. We also describe the Hikita-Nakajima isomorphism above using the realization of as
the spectrum of the center of the rational Cherednik algebra corresponding to and identify all the algebras that appear in the isomorphism with the center of the degenerate cyclotomic Hecke algebra.Ph.D
A logarithmic approximation of linearly-ordered colourings
No full textA linearly ordered (LO) k-colouring of a hypergraph assigns to each vertex a colour from the set {0,1,…,k-1} in such a way that each hyperedge has a unique maximum element. Barto, Batistelli, and Berg conjectured that it is NP-hard to find an LO k-colouring of an LO 2-colourable 3-uniform hypergraph for any constant k ≥ 2 [STACS'21] but even the case k = 3 is still open. Nakajima and Živný gave polynomial-time algorithms for finding, given an LO 2-colourable 3-uniform hypergraph, an LO colouring with O^*(√n) colours [ICALP'22] and an LO colouring with O^*(n^(1/3)) colours [ACM ToCT'23]. Very recently, Louis, Newman, and Ray gave an SDP-based algorithm with O^*(n^(1/5)) colours. We present two simple polynomial-time algorithms that find an LO colouring with O(log₂(n)) colours, which is an exponential improvement
Tribo Vernonieae Cass
No full textA tribo Vernonieae possui uma distribuição pantropical, com grande parte das espécies concentradas no Brasil e África. Atualmente, são reconhecidas 21 subtribos, 126 gêneros e cerca de 1.300 espécies (KEELEY; ROBINSON 2009; ROBINSON, 2007)...Fil: Esteves, Roberto. Universidade do Estado de Rio do Janeiro; BrasilFil: Loeuille, Benoit. Universidade Federal de Pernambuco; BrasilFil: Nakajima, Jimi Naoki. Universidade Federal de Uberlândia; BrasilFil: Marques, Danilo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Soares, Polyana N.. Colégio Cenecista Dr. José Ferreira; BrasilFil: Esteves Gonçalves, Vânia. Universidade Federal do Rio de Janeiro; BrasilFil: Mendonça, Cláudia. Universidade Federal do Rio de Janeiro; BrasilFil: Dematteis, Massimiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin
Effect of zonal flow caused by microturbulence on the double tearing mode
No full textThe effect of zonal flow shear on the double tearing mode is investigated by solving the linear reduced two-fluid equations for the equilibrium including zonal flow. The zonal flow caused by microturbulence is obtained from nonlinear simulation results presented by A. Ishizawa and N. Nakajima [Phys. Plasmas 14, 040702 (2007)]. There is no clear evidence that could indicate whether the double tearing mode is stabilized or destabilized by the zonal flow.journal articl
Towards a mathematical definition of Coulomb branches of 3-dimensional N=4 gauge theories
No full textLet M be a quaternionic representation of a compact Lie group G. Physicists study the Coulomb branch of the 3-dimensional gauge theory associated with (G,M), which is a hyper-Kaehler manifold, but have no rigorous mathematical definition. When M is of a form N + N∗, we introduce a variant of the affine Grassmannian Steinberg variety, define convolution product on its equivariant Borel-Moore homology group, and show that it is commutative. We propose that it gives a mathematical definition of the coordinate ring of the Coulomb branch. (Joint work by Braverman, Finkelberg and Nakajima)Non UBCUnreviewedAuthor affiliation: Kyoto UniversityFacult
A Multi-Language Comparison of Influences on Author Verification using Character N-Grams
No full textWe create a new multi-language corpus for author verification based on Wikipedia talkpages, and evaluate the influence that differences in topic and time have on character n-gram author profiles. Topic alignment between two texts is found to increase author verification precision, and an authors writing style is found to change over time, but not more significantly after 3 years than after 1 year.Information ArchitectureWISElectrical Engineering, Mathematics and Computer Scienc
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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