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Knowledge-Based Versus Experimentally Acquired Distance And Angle Constraints For Nmr Structure Refinement, Feng Cui, Robert Jernigan, Zhijun Wu 2017 National Institutes of Health

Knowledge-Based Versus Experimentally Acquired Distance And Angle Constraints For Nmr Structure Refinement, Feng Cui, Robert Jernigan, Zhijun Wu

Robert Jernigan

Nuclear Overhauser effects (NOE) distance constraints and torsion angle constraints are major conformational constraints for nuclear magnetic resonance (NMR) structure refinement. In particular, the number of NOE constraints has been considered as an important determinant for the quality of NMR structures. Of course, the availability of torsion angle constraints is also critical for the formation of correct local conformations. In our recent work, we have shown how a set of knowledge-based short-range distance constraints can also be utilized for NMR structure refinement, as a complementary set of conformational constraints to the NOE and torsion angle constraints. In this paper, we ...


Importance Of Scale, Land Cover, And Weather On The Abundance Of Bird Species In A Managed Forest, Alexis R. Grinde, Gerald J. Niemi, Brian R. Sturtevant, Hannah Panci, Wayne Thogmartin, Peter Wolter 2017 University of Minnesota - Duluth

Importance Of Scale, Land Cover, And Weather On The Abundance Of Bird Species In A Managed Forest, Alexis R. Grinde, Gerald J. Niemi, Brian R. Sturtevant, Hannah Panci, Wayne Thogmartin, Peter Wolter

Peter Wolter

Climate change and habitat loss are projected to be the two greatest drivers of biodiversity loss over the coming century. While public lands have the potential to increase regional resilience of bird populations to these threats, long-term data are necessary to document species responses to changes in climate and habitat to better understand population vulnerabilities. We used generalized linear mixed models to determine the importance of stand-level characteristics, multi-scale land cover, and annual weather factors to the abundance of 61 bird species over a 20-year time frame in Chippewa National Forest, Minnesota, USA. Of the 61 species modeled, we were ...


Age-Structured And Vaccination Models Of Devil Facial Tumor Disease, Christopher D. Bruno, Timothy Comar, Megan O. Powell, Adjo Tameklo 2017 University of St. Francis

Age-Structured And Vaccination Models Of Devil Facial Tumor Disease, Christopher D. Bruno, Timothy Comar, Megan O. Powell, Adjo Tameklo

Spora: A Journal of Biomathematics

Tasmanian devil populations have been devastated by devil facial tumor disease (DFTD) since its first appearance in 1996. The average lifespan of a devil has decreased from six years to three years. We present an age-structured model to represent how the disease has affected the age and breeding structures of the population. We show that with the recent increase in the breeding of juvenile devils, the overall devil population will increase but not nearly to pre-DFTD levels. The basic reproductive number may be increased with the influx of young breeding devils. In addition, our model shows that the release of ...


Optimized Adaptive Enrichment Designs For Multi-Arm Trials: Learning Which Subpopulations Benefit From Different Treatments, Jon Arni Steingrimsson, Joshua Betz, Tiachen Qian, Michael Rosenblum 2017 Department of Biostatistics, Brown School of Public Health

Optimized Adaptive Enrichment Designs For Multi-Arm Trials: Learning Which Subpopulations Benefit From Different Treatments, Jon Arni Steingrimsson, Joshua Betz, Tiachen Qian, Michael Rosenblum

Johns Hopkins University, Dept. of Biostatistics Working Papers

We propose a class of adaptive randomized trial designs for comparing two treatments to a common control in two disjoint subpopulations. The type of adaptation, called adaptive enrichment, involves a preplanned rule for modifying enrollment and arm assignment based on accruing data in an ongoing trial. The motivation for this adaptive feature is that interim data may indicate that a subpopulation, such as those with lower disease severity at baseline, are unlikely to benefit from a particular treatment, while uncertainty remains for the other treatment and/or subpopulation. We developed a new multiple testing procedure tailored to this design problem ...


Search For Transient Gravitational Waves In Coincidence With Short-Duration Radio Transients During 2007-2013, B. P. Abbott, K. Gill, B. Hughey, D. Stiles, M. Szczepanczyk, M. Zanolin, et al. 2017 California Institute of Technology

Search For Transient Gravitational Waves In Coincidence With Short-Duration Radio Transients During 2007-2013, B. P. Abbott, K. Gill, B. Hughey, D. Stiles, M. Szczepanczyk, M. Zanolin, Et Al.

Michele Zanolin

We present an archival search for transient gravitational-wave bursts in coincidence with 27 single pulse triggers from Green Bank Telescope pulsar surveys, using the LIGO, Virgo and GEO interferometer network. We also discuss a check for gravitational-wave signals in coincidence with Parkes Fast Radio Bursts using similar methods. Data analyzed in these searches were collected between 2007 and 2013. Possible sources of emission of both short-duration radio signals and transient gravitational-wave emission include starquakes on neutron stars, binary coalescence of neutron stars, and cosmic string cusps. While no evidence for gravitational-wave emission in coincidence with these radio transients was found ...


Gw151226: Observation Of Gravitational Waves From A 22-Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepanczyk, M. Zanolin, et al. 2017 California Institute of Technology

Gw151226: Observation Of Gravitational Waves From A 22-Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepanczyk, M. Zanolin, Et Al.

Michele Zanolin

We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5 σ. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 ...


Addressing Endogeneity In Actor-Speci Fi C Network Measures, Frederick J. Boehmke, Olga Chyzh, Cameron G. Thies 2017 University of Iowa

Addressing Endogeneity In Actor-Speci Fi C Network Measures, Frederick J. Boehmke, Olga Chyzh, Cameron G. Thies

Frederick J Boehmke

The study of international relations (IR), and political science more broadly, has derived great benefits from the recent growth of conceptualizing and modeling political phenomena within their broader network contexts. More than just a novel approach to evaluating the old puzzles, network analysis provides a whole new way of theoretical thinking. Challenging the traditional dyad-driven approach to the study of IR, networks highlight actor interdependence that goes beyond dyads and emphasizes that many traditional IR variables, such as conflict, trade, alliances, or international organization memberships must be treated and studied as networks. Properties of these networks (e.g., polarization, density ...


Synthesis And Functionalization Of Small Silver Nanoparticles, Chris Menter, Jeunghoon Lee, Sarah Rhen, Elton Graugnard, Bernard Yurke, William Knowlton, Will Hughes, Wan Kuang 2017 Department of Chemistry, Boise State University

Synthesis And Functionalization Of Small Silver Nanoparticles, Chris Menter, Jeunghoon Lee, Sarah Rhen, Elton Graugnard, Bernard Yurke, William Knowlton, Will Hughes, Wan Kuang

William B. Knowlton

Metal nanoparticles in general exhibit interesting properties due to their small sizes. This response shows up as an intense absorption band in the visible region making metallic nanoparticles ideal probes for medical imaging as well as for countless other applications. Functionalizing metallic nanoparticles with DNA enables targeted labeling, controlled by their base sequence. Another purpose of functionalization is to attach the nanoparticle to a DNA substrate allowing controlled bottom up engineering of nanoscale devices. Gold or gold-encapsulated silver is usually used for these purposes instead of bare silver due to the ease with which silver is oxidized although silver nanoparticles ...


Undergraduate Research Opportunities In Microelectronics At Boise State University, S. Burkett, J. Lusth, D. Russell, W. B. Knowlton, S. Parke 2017 Boise State University

Undergraduate Research Opportunities In Microelectronics At Boise State University, S. Burkett, J. Lusth, D. Russell, W. B. Knowlton, S. Parke

William B. Knowlton

Several opportunities exist for undergraduates in the Microelectronics area at Boise State University. This paper will describe the Research Experience for Undergraduates (REU) program funded by the National Science Foundation and other opportunities that have resulted for undergraduates due to external support. BSU became a NSF REU site for Microelectronics research in 1999. Each year 10 students are recruited nation-wide from various engineering and science disciplines to come to BSU for 8 weeks. The students work intensively with various faculty advisors and graduate student mentors. Another unique feature of our program is the tie to local industry. In 1999-2001, three ...


Linking Taxonomic Diversity And Trophic Function: A Graph-Based Theoretical Approach, Marcella M. Jurotich, Kaitlyn Dougherty, Barbara Hayford, Sally Clark 2017 Wayne State College

Linking Taxonomic Diversity And Trophic Function: A Graph-Based Theoretical Approach, Marcella M. Jurotich, Kaitlyn Dougherty, Barbara Hayford, Sally Clark

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The purpose of this study is to develop a novel, visual method in analyzing complex functional trait data in freshwater ecology. We focus on macroinvertebrates in stream ecosystems under a gradient of habitat degradation and employ a combination of taxonomic and functional trait diversity analyses. Then we use graph theory to link changes in functional trait diversity to taxonomic richness and habitat degradation. We test the hypotheses that: 1) taxonomic diversity and trophic functional trait diversity both decrease with increased habitat degradation; 2) loss of taxa leads to a decrease in trophic function as visualized using a bipartite graph; and ...


Nilpotent Linear Transformations And The Solvability Of Power-Associative Nilalgebras, Ivan Correa, Irvin R. Hentzel, Pedro Pablo Julca, Luiz Antonio Peresi 2017 Universidad de La Serena

Nilpotent Linear Transformations And The Solvability Of Power-Associative Nilalgebras, Ivan Correa, Irvin R. Hentzel, Pedro Pablo Julca, Luiz Antonio Peresi

Irvin Roy Hentzel

We prove some results about nilpotent linear transformations. As an application we solve some cases of Albert’s problem on the solvability of nilalgebras. More precisely, we prove the following results: commutative power-associative nilalgebras of dimension n and nilindex n − 1 or n − 2 are solvable; commutative power-associative nilalgebras of dimension 7 are solvable.


Nuclear Elements Of Degree 6 In The Free Alternative Algebra, Irvin R. Hentzel, L. A. Peresi 2017 Iowa State University

Nuclear Elements Of Degree 6 In The Free Alternative Algebra, Irvin R. Hentzel, L. A. Peresi

Irvin Roy Hentzel

We construct five new elements of degree 6 in the nucleus of the free alternative algebra. We use the representation theory of the symmetric group to locate the elements. We use the computer algebra system ALBERT and an extension of ALBERT to express the elements in compact form and to show that these new elements are not a consequence of the known degree-5 elements in the nucleus. We prove that these five new elements and four known elements form a basis for the subspace of nuclear elements of degree 6. Our calculations are done using modular arithmetic to save memory ...


Solvability Of Commutative Right-Nilalgebras Satisfying (B (Aa)) A= B ((Aa) A), Ivan Correa, Alicia Labra, Irvin R. Hentzel 2017 Universidad de Chile

Solvability Of Commutative Right-Nilalgebras Satisfying (B (Aa)) A= B ((Aa) A), Ivan Correa, Alicia Labra, Irvin R. Hentzel

Irvin Roy Hentzel

We study commutative right-nilalgebras of right-nilindex four satisfying the identity (b(aa))a = b((aa)a). Our main result is that these algebras are solvable and not necessarily nilpotent. Our results require characteristic ≠ 2, 3, 5.


Invariant Nonassociative Algebra Structures On Irreducible Representations Of Simple Lie Algebras, Murray Bremner, Irvin R. Hentzel 2017 University of Saskatchewan

Invariant Nonassociative Algebra Structures On Irreducible Representations Of Simple Lie Algebras, Murray Bremner, Irvin R. Hentzel

Irvin Roy Hentzel

An irreducible representation of a simple Lie algebra can be a direct summand of its own tensor square. In this case, the representation admits a nonassociative algebra structure which is invariant in the sense that the Lie algebra acts as derivations. We study this situation for the Lie algebra sl(2).


The Nucleus Of The Free Alternative Algebra, Irvin R. Hentzel, L. A. Peresi 2017 Iowa State University

The Nucleus Of The Free Alternative Algebra, Irvin R. Hentzel, L. A. Peresi

Irvin Roy Hentzel

We use a computer procedure to determine a basis of the elements of degree 5 in the nucleus of the free alternative algebra. In order to save computer memory, we do our calculations over the field Z103. All calculations are made with multilinear identities. Our procedure is also valid for other characteristics and for determining nuclear elements of higher degree.


Rings With (A, B, C) = (A, C, B) And (A, [B, C]D) = 0: A Case Study Using Albert, Irvin R. Hentzel, D. P. Jacobs, Erwin Kleinfeld 2017 Iowa State University

Rings With (A, B, C) = (A, C, B) And (A, [B, C]D) = 0: A Case Study Using Albert, Irvin R. Hentzel, D. P. Jacobs, Erwin Kleinfeld

Irvin Roy Hentzel

Albert is an interactive computer system for building nonassociative algebras [2]. In this paper, we suggest certain techniques for using Albert that allow one to posit and test hypotheses effectively. This process provides a fast way to achieve new results, and interacts nicely with traditional methods. We demonstrate the methodology by proving that any semiprime ring, having characteristic ≠ 2, 3, and satisfying the identities (a, b, c) - (a, c, b) = (a, [b, c], d) = 0, is associative. This generalizes a recent result by Y. Paul [7].


A Variety Containing Jordan And Pseudo-Composition Algebras, Irvin R. Hentzel, Luiz Antonio Peresi 2017 Iowa State University

A Variety Containing Jordan And Pseudo-Composition Algebras, Irvin R. Hentzel, Luiz Antonio Peresi

Irvin Roy Hentzel

We consider 3-Jordan algebras, i.e., the nonassociative commutative algebras satisfying (x^3 y)x=x^3(yx). The variety of 3-Jordan algebras contains all Jordan algebras and all pseudo-composition algebras. We prove that a simple 3-Jordan algebra with idempotent is either a Jordan algebra or a pseudo-composition algebra.


Commutative Finitely Generated Algebras Satisfying ((Yx)X)X=0 Are Solvable, Ivan Correa, Irvin R. Hentzel 2017 Universidad Metropolitana de Ciencias de la Educación

Commutative Finitely Generated Algebras Satisfying ((Yx)X)X=0 Are Solvable, Ivan Correa, Irvin R. Hentzel

Irvin Roy Hentzel

No abstract provided.


Identities Relating The Jordan Product And The Associator In The Free Nonassociative Algebra, Murray R. Bremner, Irvin R. Hentzel 2017 University of Saskatchewan

Identities Relating The Jordan Product And The Associator In The Free Nonassociative Algebra, Murray R. Bremner, Irvin R. Hentzel

Irvin Roy Hentzel

We determine the identities of degree ≤ 6 satisfied by the symmetric (Jordan) product a○b = ab + ba and the associator [a,b,c] = (ab)c - a(bc) in every nonassociative algebra. In addition to the commutative identity a○b = b○a we obtain one new identity in degree 4 and another new identity in degree 5. We demonstrate the existence of further new identities in degree 6. These identities define a variety of binary-ternary algebras which generalizes the variety of Jordan algebras in the same way that Akivis algebras generalize Lie algebras.


Generalized Alternative And Malcev Algebras, Irvin R. Hentzel, H.F. Smith 2017 Iowa State University

Generalized Alternative And Malcev Algebras, Irvin R. Hentzel, H.F. Smith

Irvin Roy Hentzel

No abstract provided.


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