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224 results on '"Guralnick, R"'

1. Generic stabilizers in actions of simple algebraic groups II: higher Grassmannian varieties

Author

Guralnick, R. M. and Lawther, R.

Subjects
Mathematics - Group Theory, Mathematics - Algebraic Geometry, 20G05
Abstract

This is the second of two papers treating faithful actions of simple algebraic groups on irreducible modules and on the associated Grassmannian varieties; in the first paper we considered the module itself and its projective space, while here we handle the varieties comprising the subspaces of the module of fixed dimension greater than one. By explicit calculation, we show that in each case, with essentially one exception, there is a dense open subset any point of which has stabilizer conjugate to a fixed subgroup, called the generic stabilizer. We provide tables listing generic stabilizers in the cases where they are non-trivial; in addition we decide whether or not there is a dense orbit., Comment: This article was combined with another. The combined version is arxiv:1904.13375v2

Published
2019

2. Generic stabilizers in actions of simple algebraic groups

Author

Guralnick, R. M. and Lawther, R.

Subjects
Mathematics - Group Theory, Mathematics - Algebraic Geometry, 20G05
Abstract

In this paper we treat faithful actions of simple algebraic groups on irreducible modules and on the associated Grassmannian varieties. By explicit calculation, we show that in each case, with essentially one exception, there is a dense open subset any point of which has stabilizer conjugate to a fixed subgroup, called the generic stabilizer. We provide tables listing generic stabilizers in the cases where they are non-trivial; in addition we decide whether or not there is a dense orbit, or a regular orbit for the action on the module., Comment: 302 pages, to appear in Memoirs, AMS

Published
2019

6. Remarks on Proficient groups

Author

Guralnick, R. M., Kantor, W. M., Kassabov, M., and Lubotzky, A.

Subjects
Mathematics - Group Theory
Abstract

If a finite group G has a presentation with d generators and r relations, it is well-known that r - d is at least the rank of the Schur multiplier of G; a presentation is called efficient if equality holds. There is an analogous definition for proficient profinite presentations. We show that many perfect groups have proficient presentations. Moreover, we prove that infinitely many alternating groups, symmetric groups and their double covers have proficient presentations

Published
2009

7. Presentations of finite simple groups: a computational approach

Author

Guralnick, R. M., Kantor, W. M., Kassabov, M., and Lubotzky, A.

Subjects
Mathematics - Group Theory, Mathematics - Combinatorics, 20D06, 20F05 (Primary), 20J06 (Secondary)
Abstract

All nonabelian finite simple groups of rank $n$ over a field of size $q$, with the possible exception of the Ree groups $^2G_2(3^{2e+1})$, have presentations with at most $80 $ relations and bit-length $O(\log n +\log q)$. Moreover, $A_n$ and $S_n$ have presentations with 3 generators$,$ 7 relations and bit-length $O(\log n)$, while $\SL(n,q)$ has a presentation with 7 generators, $2 5$ relations and bit-length $O(\log n +\log q)$., Comment: 48 pages

Published
2008

8. Weakly Closed Unipotent Subgroups in Chevalley Groups

Author

Guralnick, R. and Roehrle, G

Subjects
Mathematics - Group Theory, 20D06, 20G40, 20G15
Abstract

The goal of this note is to classify the weakly closed unipotent subgroups in the split Chevalley groups. In an application we show under some mild assumptions on the characteristic that the Lie algebra of a connected simple algebraic group fails to be a so called 2F-module.

Published
2005

9. Thompson-like characterization of the solvable radical

Author

Guralnick, R., Kunyavskii, B., Plotkin, E., and Shalev, A.

Subjects
Mathematics - Group Theory, 20F16
Abstract

We prove that the solvable radical of a finite group G coincides with the set of elements y having the following property: for any x in G the subgroup of G generated by x and y is solvable. We present analogues of this result for finite dimensional Lie algebras and some classes of infinite groups. We also consider a similar problem for pairs of elements., Comment: 13 pages; completely revised and extended version

Published
2005

10. Polynomials which are locally reducible

Author

Guralnick, R., Schacher, M., and Sonn, J.

Subjects
Mathematics - Number Theory
Abstract

Let $K$ be a global field and $n > 1$ an integer. We show $n$ is composite if and only if there is an irreducible polynomial $f(x) \in K[x]$ of degree $n$ which is reducible $q$-adically for all the primes $q$ of $K$.

Published
2004

14. Specimen collection: An essential tool

Author

Rocha, L. A., Aleixo, A., Allen, G., Almeda, F., Baldwin, C. C., Barclay, M. V. L., Bates, J. M., Bauer, A. M., Benzoni, F., Berns, C. M., Berumen, M. L., Blackburn, D. C., Blum, S., Bolaños, F., Bowie, R. C. K., Britz, R., Brown, R. M., Cadena, C. D., Carpenter, K., Ceríaco, L. M., Chakrabarty, P., Chaves, G., Choat, J. H., Clements, K. D., Collette, B. B., Collins, A., Coyne, J., Cracraft, J., Daniel, T., de Carvalho, M. R., de Queiroz, K., Di Dario, F., Drewes, R., Dumbacher, J. P., Engilis, A., Erdmann, M. V., Eschmeyer, W., Feldman, C. R., Fisher, B. L., Fjeldså, J., Fritsch, P. W., Fuchs, J., Getahun, A., Gill, A., Gomon, M., Gosliner, T., Graves, G. R., Griswold, C. E., Guralnick, R., Hartel, K., Helgen, K. M., Ho, H., Iskandar, D. T., Iwamoto, T., Jaafar, Z., James, H. F., Johnson, D., Kavanaugh, D., Knowlton, N., Lacey, E., Larson, H. K., Last, P., Leis, J. M., Lessios, H., Liebherr, J., Lowman, M., Mahler, D. L., Mamonekene, V., Matsuura, K., Mayer, G. C., Mays, H., McCosker, J., McDiarmid, R. W., McGuire, J., Miller, M. J., Mooi, R., Mooi, R. D., Moritz, C., Myers, P., Nachman, M. W., Nussbaum, R. A., Foighil, D. Ó, Parenti, L. R., Parham, J. F., Paul, E., Paulay, G., Pérez-Emán, J., Pérez-Matus, A., Poe, S., Pogonoski, J., Rabosky, D. L., Randall, J. E., Reimer, J. D., Robertson, D. R., Rödel, M.-O., Rodrigues, M. T., Roopnarine, P., Rüber, L., Ryan, M. J., Sheldon, F., Shinohara, G., Short, A., Simison, W. B., Smith-Vaniz, W. F., Springer, V. G., Stiassny, M., Tello, J. G., Thompson, C. W., Trnski, T., Tucker, P., Valqui, T., Vecchione, M., Verheyen, E., Wainwright, P. C., Wheeler, T. A., White, W. T., Will, K., Williams, J. T., Williams, G., Wilson, E. O., Winker, K., Winterbottom, R., and Witt, C. C.

Published
2014

15. The global distribution of known and undiscovered ant biodiversity

Author

Kass, J.M. Guenard, B. Dudley, K.L. Jenkins, C.N. Azuma, F. Fisher, B.L. Parr, C.L. Gibb, H. Longino, J.T. Ward, P.S. Chao, A. Lubertazzi, D. Weiser, M. Jetz, W. Guralnick, R. Blatrix, R. Lauriers, J.D. Donoso, D.A. Georgiadis, C. Gomez, K. Hawkes, P.G. Johnson, R.A. Lattke, J.E. MacGown, J.A. Mackay, W. Robson, S. Sanders, N.J. Dunn, R.R. Economo, E.P. and Kass, J.M. Guenard, B. Dudley, K.L. Jenkins, C.N. Azuma, F. Fisher, B.L. Parr, C.L. Gibb, H. Longino, J.T. Ward, P.S. Chao, A. Lubertazzi, D. Weiser, M. Jetz, W. Guralnick, R. Blatrix, R. Lauriers, J.D. Donoso, D.A. Georgiadis, C. Gomez, K. Hawkes, P.G. Johnson, R.A. Lattke, J.E. MacGown, J.A. Mackay, W. Robson, S. Sanders, N.J. Dunn, R.R. Economo, E.P.

Abstract

Invertebrates constitute the majority of animal species and are critical for ecosystem functioning and services. Nonetheless, global invertebrate biodiversity patterns and their congruences with vertebrates remain largely unknown. We resolve the first high-resolution (∼20-km) global diversity map for a major invertebrate clade, ants, using biodiversity informatics, range modeling, and machine learning to synthesize existing knowledge and predict the distribution of undiscovered diversity. We find that ants and different vertebrate groups have distinct features in their patterns of richness and rarity, underscoring the need to consider a diversity of taxa in conservation. However, despite their phylogenetic and physiological divergence, ant distributions are not highly anomalous relative to variation among vertebrate clades. Furthermore, our models predict that rarity centers largely overlap (78%), suggesting that general forces shape endemism patterns across taxa. This raises confidence that conservation of areas important for small-ranged vertebrates will benefit invertebrates while providing a "treasure map" to guide future discovery. © 2022 American Association for the Advancement of Science. All rights reserved.

Published
2022

16. Expert range maps of global mammal distributions harmonised to three taxonomic authorities

Author

Marsh, CJ, Sica, YV, Burgin, CJ, Dorman, WA, Anderson, RC, del Toro Mijares, I, Vigneron, JG, Barve, V, Dombrowik, VL, Duong, M, Guralnick, R, Hart, JA, Maypole, JK, McCall, K, Ranipeta, A, Schuerkmann, A, Torselli, MA, Lacher, T, Mittermeier, RA, Rylands, AB, Sechrest, W, Wilson, DE, Abba, AM, Aguirre, LF, Arroyo-Cabrales, J, Astua, D, Baker, AM, Braulik, G, Braun, JK, Brito, J, Busher, PE, Burneo, SF, Camacho, MA, Cavallini, P, de Almeida Chiquito, E, Cook, JA, Cserkesz, T, Csorba, G, Cuellar Soto, E, da Cunha Tavares, V, Davenport, TRB, Demere, T, Denys, C, Dickman, CR, Eldridge, MDB, Fernandez-Duque, E, Francis, CM, Frankham, G, Franklin, WL, Freitas, T, Friend, JA, Gadsby, EL, Garbino, GST, Gaubert, P, Giannini, N, Giarla, T, Gilchrist, JS, Gongora, J, Goodman, SM, Gursky-Doyen, S, Hacklander, K, Hafner, MS, Hawkins, M, Helgen, KM, Heritage, S, Hinckley, A, Hintsche, S, Holden, M, Holekamp, KE, Honeycutt, RL, Huffman, BA, Humle, T, Hutterer, R, Ibanez Ulargui, C, Jackson, SM, Janecka, J, Janecka, M, Jenkins, P, Juskaitis, R, Juste, J, Kays, R, Kilpatrick, CW, Kingston, T, Koprowski, JL, Krystufek, B, Lavery, T, Lee, TE, Leite, YLR, Novaes, RLM, Lim, BK, Lissovsky, A, Lopez-Antonanzas, R, Lopez-Baucells, A, MacLeod, CD, Maisels, FG, Mares, MA, Marsh, H, Mattioli, S, Meijaard, E, Monadjem, A, Morton, FB, Musser, G, Nadler, T, Norris, RW, Ojeda, A, Ordonez-Garza, N, Pardinas, UFJ, Patterson, BD, Pavan, A, Pennay, M, Pereira, C, Prado, J, Queiroz, HL, Richardson, M, Riley, EP, Rossiter, SJ, Rubenstein, DI, Ruelas, D, Salazar-Bravo, J, Schai-Braun, S, Schank, CJ, Schwitzer, C, Sheeran, LK, Shekelle, M, Shenbrot, G, Soisook, P, Solari, S, Southgate, R, Superina, M, Taber, AB, Talebi, M, Taylor, P, Vu Dinh, T, Ting, N, Tirira, DG, Tsang, S, Turvey, ST, Valdez, R, Van Cakenberghe, V, Veron, G, Wallis, J, Wells, R, Whittaker, D, Williamson, EA, Wittemyer, G, Woinarski, J, Zinner, D, Upham, NS, Jetz, W, Marsh, CJ, Sica, YV, Burgin, CJ, Dorman, WA, Anderson, RC, del Toro Mijares, I, Vigneron, JG, Barve, V, Dombrowik, VL, Duong, M, Guralnick, R, Hart, JA, Maypole, JK, McCall, K, Ranipeta, A, Schuerkmann, A, Torselli, MA, Lacher, T, Mittermeier, RA, Rylands, AB, Sechrest, W, Wilson, DE, Abba, AM, Aguirre, LF, Arroyo-Cabrales, J, Astua, D, Baker, AM, Braulik, G, Braun, JK, Brito, J, Busher, PE, Burneo, SF, Camacho, MA, Cavallini, P, de Almeida Chiquito, E, Cook, JA, Cserkesz, T, Csorba, G, Cuellar Soto, E, da Cunha Tavares, V, Davenport, TRB, Demere, T, Denys, C, Dickman, CR, Eldridge, MDB, Fernandez-Duque, E, Francis, CM, Frankham, G, Franklin, WL, Freitas, T, Friend, JA, Gadsby, EL, Garbino, GST, Gaubert, P, Giannini, N, Giarla, T, Gilchrist, JS, Gongora, J, Goodman, SM, Gursky-Doyen, S, Hacklander, K, Hafner, MS, Hawkins, M, Helgen, KM, Heritage, S, Hinckley, A, Hintsche, S, Holden, M, Holekamp, KE, Honeycutt, RL, Huffman, BA, Humle, T, Hutterer, R, Ibanez Ulargui, C, Jackson, SM, Janecka, J, Janecka, M, Jenkins, P, Juskaitis, R, Juste, J, Kays, R, Kilpatrick, CW, Kingston, T, Koprowski, JL, Krystufek, B, Lavery, T, Lee, TE, Leite, YLR, Novaes, RLM, Lim, BK, Lissovsky, A, Lopez-Antonanzas, R, Lopez-Baucells, A, MacLeod, CD, Maisels, FG, Mares, MA, Marsh, H, Mattioli, S, Meijaard, E, Monadjem, A, Morton, FB, Musser, G, Nadler, T, Norris, RW, Ojeda, A, Ordonez-Garza, N, Pardinas, UFJ, Patterson, BD, Pavan, A, Pennay, M, Pereira, C, Prado, J, Queiroz, HL, Richardson, M, Riley, EP, Rossiter, SJ, Rubenstein, DI, Ruelas, D, Salazar-Bravo, J, Schai-Braun, S, Schank, CJ, Schwitzer, C, Sheeran, LK, Shekelle, M, Shenbrot, G, Soisook, P, Solari, S, Southgate, R, Superina, M, Taber, AB, Talebi, M, Taylor, P, Vu Dinh, T, Ting, N, Tirira, DG, Tsang, S, Turvey, ST, Valdez, R, Van Cakenberghe, V, Veron, G, Wallis, J, Wells, R, Whittaker, D, Williamson, EA, Wittemyer, G, Woinarski, J, Zinner, D, Upham, NS, and Jetz, W

Abstract

AIM: Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW). LOCATION: Global. TAXON: All extant mammal species. METHODS: Range maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species). RESULTS: Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use. MAIN CONCLUSION: Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control.

Published
2022

18. Specimen collection: An essential tool

Author

Sills, Jennifer, Rocha, L. A., Aleixo, A., Allen, G., Almeda, F., Baldwin, C. C., Barclay, M. V.L., Bates, J. M., Bauer, A. M., Benzoni, F., Berns, C. M., Berumen, M. L., Blackburn, D. C., Blum, S., Bolaños, F., Bowie, R. C. K., Britz, R., Brown, R. M., Cadena, C. D., Carpenter, K., Ceríaco, L. M., Chakrabarty, P., Chaves, G., Choat, J. H., Clements, K. D., Collette, B. B., Collins, A., Coyne, J., Cracraft, J., Daniel, T., de Carvalho, M. R., de Queiroz, K., Di Dario, F., Drewes, R., Dumbacher, J. P., Engilis, A., Jr., Erdmann, M. V., Eschmeyer, W., Feldman, C. R., Fisher, B. L., Fjeldså, J., Fritsch, P. W., Fuchs, J., Getahun, A., Gill, A., Gomon, M., Gosliner, T., Graves, G. R., Griswold, C. E., Guralnick, R., Hartel, K., Helgen, K. M., Ho, H., Iskandar, D. T., Iwamoto, T., Jaafar, Z., James, H. F., Johnson, D., Kavanaugh, D., Knowlton, N., Lacey, E., Larson, H. K., Last, P., Leis, J. M., Lessios, H., Liebherr, J., Lowman, M., Mahler, D. L., Mamonekene, V., Matsuura, K., Mayer, G. C., Mays, H., Jr., McCosker, J., McDiarmid, R. W., McGuire, J., Miller, M. J., Mooi, R., Mooi, R. D., Moritz, C., Myers, P., Nachman, M. W., Nussbaum, R. A., Foighil, D. Ó, Parenti, L. R., Parham, J. F., Paul, E., Paulay, G., Pérez-Emán, J., Pérez-Matus, A., Poe, S., Pogonoski, J., Rabosky, D. L., Randall, J. E., Reimer, J. D., Robertson, D. R., Rödel, M.-O., Rodrigues, M. T., Roopnarine, P., Rüber, L., Ryan, M. J., Sheldon, F., Shinohara, G., Short, A., Simison, W. B., Smith-Vaniz, W. F., Springer, V. G., Stiassny, M., Tello, J. G., Thompson, C. W., Trnski, T., Tucker, P., Valqui, T., Vecchione, M., Verheyen, E., Wainwright, P. C., Wheeler, T. A., White, W. T., Will, K., Williams, J. T., Williams, G., Wilson, E. O., Winker, K., Winterbottom, R., and Witt, C. C.

Published
2014

20. Using semistructured surveys to improve citizen science data for monitoring biodiversity

Author

Kelling, S., Johnston, A., Bonn, Aletta, Fink, D., Ruiz-Gutierrez, V., Bonney, R., Fernandez, M., Hochachka, W.M., Julliard, R., Kraemer, Roland, Guralnick, R., Kelling, S., Johnston, A., Bonn, Aletta, Fink, D., Ruiz-Gutierrez, V., Bonney, R., Fernandez, M., Hochachka, W.M., Julliard, R., Kraemer, Roland, and Guralnick, R.

Abstract

Biodiversity is being lost at an unprecedented rate, and monitoring is crucial for understanding the causal drivers and assessing solutions. Most biodiversity monitoring data are collected by volunteers throughcitizen science projects, and often crucial information is lacking to account for the inevitable biases that observers introduce during data collection. We contend that citizen science projects intended to supportbiodiversity monitoring must gather information about the observationprocess as well as species occurrence. We illustrate this using eBird, a global citizen science project that collects information on bird occurrences as well as vital contextual information on the observation process while maintaining broad participation. Our fundamental argument is that regardless of what species are being monitored, when citizen science projects collect a small set of basic information about how participants make their observations, the scientific value of the data collected will be dramatically improved.

Published
2019

21. Essential biodiversity variables for mapping and monitoring species populations

Author

Jetz, W., McGeoch, M.A., Guralnick, R., Ferrier, S., Beck, J., Costello, M.J., Fernandez, M., Geller, G.N., Keil, P., Merow, C., Meyer, C., Muller-Karger, F.E., Pereira, H.M., Regan, E.C., Schmeller, Dirk Sven, Turak, E., Jetz, W., McGeoch, M.A., Guralnick, R., Ferrier, S., Beck, J., Costello, M.J., Fernandez, M., Geller, G.N., Keil, P., Merow, C., Meyer, C., Muller-Karger, F.E., Pereira, H.M., Regan, E.C., Schmeller, Dirk Sven, and Turak, E.

Abstract

Species distributions and abundances are undergoing rapid changes worldwide. This highlights the significance of reliable, integrated information for guiding and assessing actions and policies aimed at managing and sustaining the many functions and benefits of species. Here we synthesize the types of data and approaches that are required to achieve such an integration and conceptualize ‘essential biodiversity variables’ (EBVs) for a unified global capture of species populations in space and time. The inherent heterogeneity and sparseness of raw biodiversity data are overcome by the use of models and remotely sensed covariates to inform predictions that are contiguous in space and time and global in extent. We define the species population EBVs as a space–time–species–gram (cube) that simultaneously addresses the distribution or abundance of multiple species, with its resolution adjusted to represent available evidence and acceptable levels of uncertainty. This essential information enables the monitoring of single or aggregate spatial or taxonomic units at scales relevant to research and decision-making. When combined with ancillary environmental or species data, this fundamental species population information directly underpins a range of biodiversity and ecosystem function indicators. The unified concept we present links disparate data to downstream uses and informs a vision for species population monitoring in which data collection is closely integrated with models and infrastructure to support effective biodiversity assessment.

Published
2019

22. Surjective word maps and Burnside's p^a q^b theorem

Author

Guralnick, R, Liebeck, MW, O'Brien, E, Shalev, A, and Tiep, PH

Subjects
UNIPOTENT CHARACTERS, SHARP BOUNDS, Science & Technology, General Mathematics, WARING PROBLEM, REPRESENTATIONS, PRODUCTS, 0101 Pure Mathematics, CONJUGACY CLASSES, Physical Sciences, SUBGROUPS, GROWTH, FINITE SIMPLE-GROUPS, Mathematics, EXCEPTIONAL GROUPS
Abstract

We prove surjectivity of certain word maps on finite non-abelian simple groups. More precisely, we prove the following: if N is a product of two prime powers, then the word map (x,y)↦xNyN is surjective on every finite non-abelian simple group; if N is an odd integer, then the word map (x,y,z)↦xNyNzN is surjective on every finite quasisimple group. These generalize classical theorems of Burnside and Feit–Thompson. We also prove asymptotic results about the surjectivity of the word map (x,y)↦xNyN that depend on the number of prime factors of the integer N.

Published
2018

23. Satellite sensor requirements for monitoring essential biodiversity variables of coastal ecosystems.

Author

Muller-Karger, F. E., Hestir, E., Ade, C., Turpie, K., Roberts, D., Siegel, D., Miller, R., Humm, D., Izenberg, N., Keller, M., Morgan, F., Frouin R., R., Dekker, A., Gardner, R., Goodman, J., Schaeffer, B., Franz, B., Pahlevan, N., Mannino, A. G., Concha, J. A., Ackleson, S. G., Najjar, R., Cavanaugh, K., Romanou, A., Tzortziou, M., Boss, E., Pavlick, R., Schimel, D., Freeman, A., Rousseaux, R. S., Dunne, J., Long, M., Klein, E., McKinley, G., Letelier, R., Roffer, M., Goes, J., Bracher, Astrid, Arrigo, K. R., Dierssen, H., Zhang, X., Davis, F., Best, B., Guralnick, R., Moisan, J., Sosik, H. M., Kavanaugh, M., Kudela, R., Mouw, C. B., Barnard, A., Palacios, S., Roessler, C., Drakou, E., Appeltans, W., Muller-Karger, F. E., Hestir, E., Ade, C., Turpie, K., Roberts, D., Siegel, D., Miller, R., Humm, D., Izenberg, N., Keller, M., Morgan, F., Frouin R., R., Dekker, A., Gardner, R., Goodman, J., Schaeffer, B., Franz, B., Pahlevan, N., Mannino, A. G., Concha, J. A., Ackleson, S. G., Najjar, R., Cavanaugh, K., Romanou, A., Tzortziou, M., Boss, E., Pavlick, R., Schimel, D., Freeman, A., Rousseaux, R. S., Dunne, J., Long, M., Klein, E., McKinley, G., Letelier, R., Roffer, M., Goes, J., Bracher, Astrid, Arrigo, K. R., Dierssen, H., Zhang, X., Davis, F., Best, B., Guralnick, R., Moisan, J., Sosik, H. M., Kavanaugh, M., Kudela, R., Mouw, C. B., Barnard, A., Palacios, S., Roessler, C., Drakou, E., and Appeltans, W.

Abstract

The biodiversity and high productivity of coastal terrestrial and aquatic habitats are the foundation for important benefits to human societies around the world. These globally distributed habitats need frequent and broad systematic assessments, but field surveys only cover a small fraction of these areas. Satellite-based sensors can repeatedly record the visible and near-infrared reflectance spectra that contain the absorption, scattering, and fluorescence signatures of functional phytoplankton groups, colored dissolved matter, and particulate matter near the surface ocean, and of biologically structured habitats (floating and emergent vegetation, benthic habitats like coral, seagrass, and algae). These measures can be incorporated into Essential Biodiversity Variables (EBVs), including the distribution, abundance, and traits of groups of species populations, and used to evaluate habitat fragmentation. However, current and planned satellites are not designed to observe the EBVs that change rapidly with extreme tides, salinity, temperatures, storms, pollution, or physical habitat destruction over scales relevant to human activity. Making these observations requires a new generation of satellite sensors able to sample with these combined characteristics: (1) spatial resolution on the order of 30 to 100-m pixels or smaller; (2) spectral resolution on the order of 5 nm in the visible and 10 nm in the short-wave infrared spectrum (or at least two or more bands at 1,030, 1,240, 1,630, 2,125, and/or 2,260 nm) for atmospheric correction and aquatic and vegetation assessments; (3) radiometric quality with signal to noise ratios (SNR) above 800 (relative to signal levels typical of the open ocean), 14-bit digitization, absolute radiometric calibration <2%, relative calibration of 0.2%, polarization sensitivity <1%, high radiometric stability and linearity, and operations designed to minimize sunglint; and (4) temporal resolution of hours to days. We refer to these combined s

Published
2018

25. HISTORICAL AND BIOMECHANICAL ANALYSIS OF FUNCTIONAL AND STRUCTURAL DISSOCIATION IN THE FEEDING SYSTEMS OF MOLLUSCS

Author

Guralnick, R.

Abstract

Modifications of the molluscan feeding system has long been recognized as a crucial feature in molluscan diversification related to the important process of gathering energy from the environment. Perhaps the most obvious variability in the feeding stroke in Mollusca is whether or not the radular teeth flex laterally or remain fixed in place. Here, we use a combination of phylogenetic inference and biomechanical modeling to understand the transformational and causal basis or flexure or lack thereof. We also use the same data sets to test if subparts of systems are structurally, functionally and/or evolutionary dissociated or integrated. Results from synthesizing our data sets suggest that flexure is the plesiomorphic condition in Mollusca, with lack of flexure arising in one clade. Analysis of structural character state transformations that correlate with change function at the node suggest that dissociation of radular from cartilage is the main change leading to lack of flexure. We also show that radular and cartilage characters, contra previous comparative work, do not change in concert but instead happen independently.

Published
1998

26. On the maximal number of coprime subdegrees in finite primitive permutation groups

Author

Dolfi, S, Guralnick, R, Praeger, C, Spiga, P, Praeger, CE, SPIGA, PABLO, Dolfi, S, Guralnick, R, Praeger, C, Spiga, P, Praeger, CE, and SPIGA, PABLO

Abstract

The subdegrees of a transitive permutation group are the orbit lengths of a point stabilizer. For a finite primitive permutation group which is not cyclic of prime order, the largest subdegree shares a non-trivial common factor with each non-trivial subdegree. On the other hand, it is possible for non-trivial subdegrees of primitive groups to be coprime, a famous example being the rank 5 action of the small Janko group J1 on 266 points which has subdegrees of lengths 11 and 12. We prove that, for every finite primitive group, the maximal size of a set of pairwise coprime non-trivial subdegrees is at most 2.

Published
2016

27. Dealing with Trade-Offs in Destructive Sampling Designs for Occupancy Surveys

Author

Guralnick, R, Canessa, S, Heard, GW, Robertson, P, Sluiter, IRK, Guralnick, R, Canessa, S, Heard, GW, Robertson, P, and Sluiter, IRK

Abstract

Occupancy surveys should be designed to minimise false absences. This is commonly achieved by increasing replication or increasing the efficiency of surveys. In the case of destructive sampling designs, in which searches of individual microhabitats represent the repeat surveys, minimising false absences leads to an inherent trade-off. Surveyors can sample more low quality microhabitats, bearing the resultant financial costs and producing wider-spread impacts, or they can target high quality microhabitats were the focal species is more likely to be found and risk more severe impacts on local habitat quality. We show how this trade-off can be solved with a decision-theoretic approach, using the Millewa Skink Hemiergis millewae from southern Australia as a case study. Hemiergis millewae is an endangered reptile that is best detected using destructive sampling of grass hummocks. Within sites that were known to be occupied by H. millewae, logistic regression modelling revealed that lizards were more frequently detected in large hummocks. If this model is an accurate representation of the detection process, searching large hummocks is more efficient and requires less replication, but this strategy also entails destruction of the best microhabitats for the species. We developed an optimisation tool to calculate the minimum combination of the number and size of hummocks to search to achieve a given cumulative probability of detecting the species at a site, incorporating weights to reflect the sensitivity of the results to a surveyor's priorities. The optimisation showed that placing high weight on minimising volume necessitates impractical replication, whereas placing high weight on minimising replication requires searching very large hummocks which are less common and may be vital for H. millewae. While destructive sampling methods are sometimes necessary, surveyors must be conscious of the ecological impacts of these methods. This study provides a simple tool for identify

Published
2015

30. Specimen collection: An essential tool

Author

Rocha, L, Aleixo, A, Allen, G, Almeda, F, Baldwin, C, Barclay, M, Bates, J, Bauer, A, Benzoni, F, Berns, C, Berumen, M, Blackburn, D, Blum, S, Bolaños, F, Bowie, R, Britz, R, Brown, R, Cadena, C, Carpenter, K, Ceríaco, L, Chakrabarty, P, Chaves, G, Choat, J, Clements, K, Collette, B, Collins, A, Coyne, J, Cracraft, J, Daniel, T, de Carvalho, M, de Queiroz, K, Di Dario, F, Drewes, R, Dumbacher, J, Engilis Jr., A, Erdmann, M, Eschmeyer, W, Feldman, C, Fisher, B, Fjeldså, J, Fritsch, P, Fuchs, J, Getahun, A, Gill, A, Gomon, M, Gosliner, T, Graves, G, Griswold, C, Guralnick, R, Hartel, K, Helgen, K, Ho, H, Iskandar, D, Iwamoto, T, Jaafar, Z, James, H, Johnson, D, Kavanaugh, D, Knowlton, N, Lacey, E, Larson, H, Last, P, Leis, J, Lessios, H, Liebherr, J, Lowman, M, Mahler, D, Mamonekene, V, Matsuura, K, Mayer, G, Mays Jr., H, Mccosker, J, Mcdiarmid, R, Mcguire, J, Miller, M, Mooi, R, Moritz, C, Myers, P, Nachman, M, Nussbaum, R, Ó Foighil, D, Parenti, L, Parham, J, Paul, E, Paulay, G, Pérez-Emán, J, Pérez-Matus, A, Poe, S, Pogonoski, J, Rabosky, D, Randall, J, Reimer, J, Robertson, D, Rödel, M, Rodrigues, M, Roopnarine, P, Rüber, L, Ryan, M, Sheldon, F, Shinohara, G, Short, A, Simison, W, Smith-Vaniz, W, Springer, V, Stiassny, M, Tello, J, Thompson, C, Trnski, T, Tucker, P, Valqui, T, Vecchione, M, Verheyen, E, Wainwright, P, Wheeler, T, White, W, Will, K, Williams, J, Williams, G, Wilson, E, Winker, K, Winterbottom, R, Witt, C, Rocha, LA, Baldwin, CC, Barclay, MVL, Bates, JM, Bauer, AM, Berns, CM, Berumen, ML, Blackburn, DC, Bowie, RCK, Brown, RM, Cadena, CD, Ceríaco, LM, Choat, JH, Clements, KD, Collette, BB, de Carvalho, MR, Dumbacher, JP, Engilis Jr. , A, Erdmann, MV, Feldman, CR, Fisher, BL, Fritsch, PW, Graves, GR, Griswold, CE, Helgen, KM, Iskandar, DT, James, HF, Larson, HK, Leis, JM, Mahler, DL, Mayer, GC, Mays Jr. , H, McCosker, J, McDiarmid, RW, McGuire, J, Miller, MJ, Mooi, RD, Nachman, MW, Nussbaum, RA, Parenti, LR, Parham, JF, Rabosky, DL, Randall, JE, Reimer, JD, Robertson, DR, Rödel, M-O, Rodrigues, MT, Ryan, MJ, Simison, WB, Smith-Vaniz, WF, Springer, VG, Tello, JG, Thompson, CW, Wainwright, PC, Wheeler, TA, White, WT, Williams, JT, Wilson, EO, Witt, CC, Rocha, L, Aleixo, A, Allen, G, Almeda, F, Baldwin, C, Barclay, M, Bates, J, Bauer, A, Benzoni, F, Berns, C, Berumen, M, Blackburn, D, Blum, S, Bolaños, F, Bowie, R, Britz, R, Brown, R, Cadena, C, Carpenter, K, Ceríaco, L, Chakrabarty, P, Chaves, G, Choat, J, Clements, K, Collette, B, Collins, A, Coyne, J, Cracraft, J, Daniel, T, de Carvalho, M, de Queiroz, K, Di Dario, F, Drewes, R, Dumbacher, J, Engilis Jr., A, Erdmann, M, Eschmeyer, W, Feldman, C, Fisher, B, Fjeldså, J, Fritsch, P, Fuchs, J, Getahun, A, Gill, A, Gomon, M, Gosliner, T, Graves, G, Griswold, C, Guralnick, R, Hartel, K, Helgen, K, Ho, H, Iskandar, D, Iwamoto, T, Jaafar, Z, James, H, Johnson, D, Kavanaugh, D, Knowlton, N, Lacey, E, Larson, H, Last, P, Leis, J, Lessios, H, Liebherr, J, Lowman, M, Mahler, D, Mamonekene, V, Matsuura, K, Mayer, G, Mays Jr., H, Mccosker, J, Mcdiarmid, R, Mcguire, J, Miller, M, Mooi, R, Moritz, C, Myers, P, Nachman, M, Nussbaum, R, Ó Foighil, D, Parenti, L, Parham, J, Paul, E, Paulay, G, Pérez-Emán, J, Pérez-Matus, A, Poe, S, Pogonoski, J, Rabosky, D, Randall, J, Reimer, J, Robertson, D, Rödel, M, Rodrigues, M, Roopnarine, P, Rüber, L, Ryan, M, Sheldon, F, Shinohara, G, Short, A, Simison, W, Smith-Vaniz, W, Springer, V, Stiassny, M, Tello, J, Thompson, C, Trnski, T, Tucker, P, Valqui, T, Vecchione, M, Verheyen, E, Wainwright, P, Wheeler, T, White, W, Will, K, Williams, J, Williams, G, Wilson, E, Winker, K, Winterbottom, R, Witt, C, Rocha, LA, Baldwin, CC, Barclay, MVL, Bates, JM, Bauer, AM, Berns, CM, Berumen, ML, Blackburn, DC, Bowie, RCK, Brown, RM, Cadena, CD, Ceríaco, LM, Choat, JH, Clements, KD, Collette, BB, de Carvalho, MR, Dumbacher, JP, Engilis Jr. , A, Erdmann, MV, Feldman, CR, Fisher, BL, Fritsch, PW, Graves, GR, Griswold, CE, Helgen, KM, Iskandar, DT, James, HF, Larson, HK, Leis, JM, Mahler, DL, Mayer, GC, Mays Jr. , H, McCosker, J, McDiarmid, RW, McGuire, J, Miller, MJ, Mooi, RD, Nachman, MW, Nussbaum, RA, Parenti, LR, Parham, JF, Rabosky, DL, Randall, JE, Reimer, JD, Robertson, DR, Rödel, M-O, Rodrigues, MT, Ryan, MJ, Simison, WB, Smith-Vaniz, WF, Springer, VG, Tello, JG, Thompson, CW, Wainwright, PC, Wheeler, TA, White, WT, Williams, JT, Wilson, EO, and Witt, CC

Published
2014

31. Coprime subdegrees for primitive permutation groups and completely reducible linear groups

Author

Dolfi, S, Guralnick, R, Praeger, C, Spiga, P, SPIGA, PABLO, Dolfi, S, Guralnick, R, Praeger, C, Spiga, P, and SPIGA, PABLO

Abstract

In this paper we answer a question of Gabriel Navarro about orbit sizes of a finite linear group H aS dagger GL(V) acting completely reducibly on a vector space V: if the H-orbits containing the vectors a and b have coprime lengths m and n, we prove that the H-orbit containing a + b has length mn. Such groups H are always reducible if n,m > 1. In fact, if H is an irreducible linear group, we show that, for every pair of non-zero vectors, their orbit lengths have a non-trivial common factor. In the more general context of finite primitive permutation groups G, we show that coprime non-identity subdegrees are possible if and only if G is of O'Nan-Scott type AS, PA or TW. In a forthcoming paper we will show that, for a finite primitive permutation group, a set of pairwise coprime subdegrees has size at most 2. Finally, as an application of our results, we prove that a field has at most 2 finite extensions of pairwise coprime indices with the same normal closure

Published
2013

32. The minimum information about a genome sequence (MIGS) specification

Author

Field, D., Garrity, G., Gray, T., Morrison, N., Selengut, J., Sterk, P., Tatusova, T., Thomson, N., Allen, M.J., Angiuoli, S.V., Ashburner, M., Axelrod, N., Baldauf, S., Ballard, S., Boore, J., Cochrane, G., Cole, J., Dawyndt, P., De Vos, P., dePamphilis, C., Edwards, R., Faruque, N., Feldman, R., Gilbert, J., Gilna, P., Glöckner, F.O., Goldstein, P., Guralnick, R., Haft, D., Hancock, D., Hermjakob, H., Hertz-Fowler, C., Hugenholtz, P., Joint, I., Kagan, L., Kane, M., Kennedy, J., Kowalchuk, G.A., Kottmann, R., Kolker, E., Kravitz, S., Kyrpides, N., Leebens-Mack, J., Lewis, S.E., Li, K.W., Lister, A.L., Lord, P., Maltsev, N., Markowitz, V., Martiny, J., Methe, B., Mizrachi, I., Moxon, R., Nelson, K.E., Parkhill, J., Proctor, L., White, O., Sansone, S-A., Spiers, A., Stevens, R., Swift, P., Taylor, C., Tateno, Y., Tett, A., Turner, S., Ussery, D., Vaughan, B., Ward, N., Whetzel, T., GIil, I.S., Wilson, G., Wipat, A., Field, D., Garrity, G., Gray, T., Morrison, N., Selengut, J., Sterk, P., Tatusova, T., Thomson, N., Allen, M.J., Angiuoli, S.V., Ashburner, M., Axelrod, N., Baldauf, S., Ballard, S., Boore, J., Cochrane, G., Cole, J., Dawyndt, P., De Vos, P., dePamphilis, C., Edwards, R., Faruque, N., Feldman, R., Gilbert, J., Gilna, P., Glöckner, F.O., Goldstein, P., Guralnick, R., Haft, D., Hancock, D., Hermjakob, H., Hertz-Fowler, C., Hugenholtz, P., Joint, I., Kagan, L., Kane, M., Kennedy, J., Kowalchuk, G.A., Kottmann, R., Kolker, E., Kravitz, S., Kyrpides, N., Leebens-Mack, J., Lewis, S.E., Li, K.W., Lister, A.L., Lord, P., Maltsev, N., Markowitz, V., Martiny, J., Methe, B., Mizrachi, I., Moxon, R., Nelson, K.E., Parkhill, J., Proctor, L., White, O., Sansone, S-A., Spiers, A., Stevens, R., Swift, P., Taylor, C., Tateno, Y., Tett, A., Turner, S., Ussery, D., Vaughan, B., Ward, N., Whetzel, T., GIil, I.S., Wilson, G., and Wipat, A.

Published
2008

33. Mapping the biosphere: exploring species to understand the origin, organization and sustainability of biodiversity

Author

Wheeler, Q. D., primary, Knapp, S., additional, Stevenson, D. W., additional, Stevenson, J., additional, Blum, S. D., additional, Boom, B. M., additional, Borisy, G. G., additional, Buizer, J. L., additional, De Carvalho, M. R., additional, Cibrian, A., additional, Donoghue, M. J., additional, Doyle, V., additional, Gerson, E. M., additional, Graham, C. H., additional, Graves, P., additional, Graves, S. J., additional, Guralnick, R. P., additional, Hamilton, A. L., additional, Hanken, J., additional, Law, W., additional, Lipscomb, D. L., additional, Lovejoy, T. E., additional, Miller, H., additional, Miller, J. S., additional, Naeem, S., additional, Novacek, M. J., additional, Page, L. M., additional, Platnick, N. I., additional, Porter-Morgan, H., additional, Raven, P. H., additional, Solis, M. A., additional, Valdecasas, A. G., additional, Van Der Leeuw, S., additional, Vasco, A., additional, Vermeulen, N., additional, Vogel, J., additional, Walls, R. L., additional, Wilson, E. O., additional, and Woolley, J. B., additional

Published
2012
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45. Presentations of finite simple groups: a computational approach.

Author

Guralnick, R. M., Kantor, W. M., Kassabov, M., and Lubotzky, A.

Subjects
*FINITE simple groups, *PROGRAM generators (Computer programs), *AUTOMORPHISMS, *SYMMETRIC functions, *COMPUTATIONAL complexity
Abstract

All finite simple groups of Lie type of rank n over a field of size q, with the possible exception of the Ree groups 2G2(q), have presentations with at most 49 relations and bit-length O(log n + log q). Moreover, An and Sn have presentations with 3 generators, 7 relations and bit- length O (log n), while SL(n, q) has a presentation with 6 generators, 25 relations and bit-length O(logn + logq). [ABSTRACT FROM AUTHOR]

Published
2011
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46. The reductive subgroups of G2.

Author

Stewart, David I. and Guralnick, R. M.

Subjects
*FROBENIUS groups, *DIFFERENTIAL algebraic groups, *AUTOMORPHISMS, *SUBGROUP growth, *GROUP theory
Abstract

Let G ≔ G2( K) be a simple algebraic group of type G2 defined over an algebraically closed field K of characteristic p > 0. Let σ denote a standard Frobenius automorphism of G such that Gσ ≅ G2( q) with q ⩾ 4. In this paper we find all reductive subgroups of G and quasi-simple subgroups of Gσ in the defining characteristic. Our results extend the complete reducibility results of [Liebeck and Seitz, Mem. Amer. Math. Soc. 121: 580, 1996, Theorem 1]. [ABSTRACT FROM AUTHOR]

Published
2010
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47. The reductive subgroups of G2.

Author

Stewart, David I. and Guralnick, R. M.

Subjects
FROBENIUS groups, DIFFERENTIAL algebraic groups, AUTOMORPHISMS, SUBGROUP growth, GROUP theory
Abstract

Let G ≔ G2( K) be a simple algebraic group of type G2 defined over an algebraically closed field K of characteristic p > 0. Let σ denote a standard Frobenius automorphism of G such that Gσ ≅ G2( q) with q ⩾ 4. In this paper we find all reductive subgroups of G and quasi-simple subgroups of Gσ in the defining characteristic. Our results extend the complete reducibility results of [Liebeck and Seitz, Mem. Amer. Math. Soc. 121: 580, 1996, Theorem 1]. [ABSTRACT FROM AUTHOR]

Published
2010
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48. Intervals in the subgroup lattices of the alternating and symmetric groups of prime degree.

Author

Perepelitsky, Philipp and Guralnick, R. M.

Subjects
*SUBGROUP growth, *LATTICE theory, *ISOMORPHISM (Mathematics), *PRIME numbers, *FINITE groups
Abstract

If G is a group and H is a subgroup of G we write for the lattice of over-groups of H in G. It is an open question whether or not every finite lattice is isomorphic to some finite group interval lattice , where G is finite. We prove that no DΔ( m1, ... , mt)-lattice and few M-lattices have the form , where G is an alternating or symmetric group of prime degree. [ABSTRACT FROM AUTHOR]

Published
2009
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49. A note on arc-transitive circulant digraphs.

Author

Praeger, Cheryl E., Jing Xu, and Guralnick, R. M.

Subjects
INTEGER programming, AUTOMORPHISMS, ISOMORPHISM (Mathematics), MATHEMATICS, PRIME numbers
Abstract

We prove that, for a positive integer n and subgroup H of automorphisms of a cyclic group Z of order n, there is up to isomorphism a unique connected circulant digraph based on Z admitting an arc-transitive action of Z ⋊ H. We refine the Kovács–Li classification of arc-transitive circulants to determine those digraphs with automorphism group larger than Z ⋊ H. As an application we construct, for each prime power q, a digraph with q – 1 vertices and automorphism group equal to the semilinear group ΓL(1, q), thus proving that ΓL(1, q) is 2-closed in the sense of Wielandt. [ABSTRACT FROM AUTHOR]

Published
2009
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50. Determining a connected split reductive group from its irreducible representations.

Author

CheeWhye Chin and Guralnick, R. M.

Subjects
*ISOMORPHISM (Mathematics), *MATHEMATICS, *HOMOMORPHISMS, *GROTHENDIECK groups, *SET theory
Abstract

We show that a connected split reductive group G over a field of characteristic 0 is determined up to isomorphism by specifying a maximal torus T of G, the set of isomorphism classes of irreducible representations of G, and the character homomorphism from the Grothendieck ring of G to that of T. More precisely, we determine all isomorphisms compatible with the specified data. [ABSTRACT FROM AUTHOR]

Published
2008
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