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Wildfire Promotes Dominance Of Invasive Giant Reed (Arundo Donax) In Riparian Ecosystems, Gretchen Coffman, R F. Ambrose, P W. Rundel 2010 University of San Francisco

Wildfire Promotes Dominance Of Invasive Giant Reed (Arundo Donax) In Riparian Ecosystems, Gretchen Coffman, R F. Ambrose, P W. Rundel

Environmental Science

Widespread invasion of riparian ecosystems by the large bamboo-like grass Arundo donax L. has altered community structure and ecological function of streams in California. This study evaluated the influence of wildfire on A. donax invasion by investigating its relative rate of reestablishment versus native riparian species after wildfire burned 300 ha of riparian woodlands along the Santa Clara River in southern California in October 2003. Post-fire A. donax growth rates and productivity were compared to those of native woody riparian species in plots established before and after the fire. Arundo donax resprouted within days after the fire and exhibited higher ...


Reply To "Comment On 'Cooperation In An Evolutionary Prisoner's Dilemma On Networks With Degree-Degree Correlations' ", Stephen Devlin, T Treloar 2010 University of San Francisco

Reply To "Comment On 'Cooperation In An Evolutionary Prisoner's Dilemma On Networks With Degree-Degree Correlations' ", Stephen Devlin, T Treloar

Mathematics

We respond to the comment of Zhu et al. [Phys. Rev. E 82, 038101 (2010)] and show that the results in question are not misleading.


Representing Synonymity In Causal Logic And In Logic Programming, Joohyung Lee, Yuliya Lierler, Vladimir Lifschitz, Fangkai Yang 2010 Arizona State University

Representing Synonymity In Causal Logic And In Logic Programming, Joohyung Lee, Yuliya Lierler, Vladimir Lifschitz, Fangkai Yang

Computer Science Faculty Proceedings & Presentations

We investigate the relationship between rules representing synonymity in nonmonotonic causal logic and in answer set programming. This question is of interest in connection with current work on modular languages for describing actions.


A Chloroacetamidine-Based Inactivator Of Protein Arginine Methyltransferase 1: Design, Synthesis, And In Vitro And In Vivo Evaluation, Obiamaka Obianyo, Corey P. Causey, Tanesha C. Osborne, Justin E. Jones, Young-Ho Lee, Michael R. Stallcup, Paul R. Thompson 2010 University of South Carolina

A Chloroacetamidine-Based Inactivator Of Protein Arginine Methyltransferase 1: Design, Synthesis, And In Vitro And In Vivo Evaluation, Obiamaka Obianyo, Corey P. Causey, Tanesha C. Osborne, Justin E. Jones, Young-Ho Lee, Michael R. Stallcup, Paul R. Thompson

Tanesha C. Osborne

Protein arginine methyltransferases (PRMTs) catalyze the post-translational methylation of arginine residues. PRMT1 is the predominant mammalian isozyme, and is responsible for generating the majority of the asymmetrically dimethylated arginine found in vivo. The dysregulation of this enzyme has been implicated in heart disease and cancer; thus, its inhibition would be useful in the treatment of these diseases. Herein, we describe the most potent PRMT1 inhibitor described to date. This compound, denoted C21, is a chloroacetamidine-containing peptide that is able to irreversibly bind and inactivate the enzyme selectively. We have also shown that the coactivator activity of PRMT1 is selectively inhibited ...


Metallization Of Nanofilms In Strong Adiabatic Electric Fields, Maxim Durach, Anastasia Rusina, Matthias F. Kling, Mark I. Stockman 2010 Georgia Southern University

Metallization Of Nanofilms In Strong Adiabatic Electric Fields, Maxim Durach, Anastasia Rusina, Matthias F. Kling, Mark I. Stockman

Maxim Durach

We introduce an effect of metallization of dielectric nanofilms by strong, adiabatically varying electric fields. The metallization causes optical properties of a dielectric film to become similar to those of a plasmonic metal (strong absorption and negative permittivity at low optical frequencies). This is a quantum effect, which is exponentially size-dependent, occurring at fields on the order of 0.1  V/Å and pulse durations ranging from ∼1  fs to ∼10  ns for a film thickness of 3–10 nm.


Modeling The Noble Metal/Tio2 (110) Interface With Hybrid Dft Functionals: A Periodic Electrostatic Embedded Cluster Model Study, Salai Cheettu Ammal, Andreas Heyden 2010 University of South Carolina - Columbia

Modeling The Noble Metal/Tio2 (110) Interface With Hybrid Dft Functionals: A Periodic Electrostatic Embedded Cluster Model Study, Salai Cheettu Ammal, Andreas Heyden

Faculty Publications

The interaction of Aun and Ptn (n=2,3) clusters with the stoichiometric and partially reduced rutile TiO2 (110) surfaces has been investigated using periodic slab and periodic electrostatic embedded cluster models. Compared to Au clusters, Pt clusters interact strongly with both stoichiometric and reduced TiO2 (110) surfaces and are able to enhance the reducibility of the TiO2 (110) surface, i.e., reduce the oxygen vacancy formation energy. The focus of this study is the effect of Hartree–Fock exchange on the description of the strength of chemical bonds at the interface of Au/Pt clusters and the TiO2 (110 ...


Distribution And Hazard Of Sulfidic Sediments In A River And Creek Channel System Of The Murray-Darling Basin: Edward-Wakool Channel System Case Study, Richard T. Bush, M Tulau, J Coughran, Nicholas J. Ward, Vanessa NL Wong, Michael D. Cheetham, David Morand 2010 Southern Cross University

Distribution And Hazard Of Sulfidic Sediments In A River And Creek Channel System Of The Murray-Darling Basin: Edward-Wakool Channel System Case Study, Richard T. Bush, M Tulau, J Coughran, Nicholas J. Ward, Vanessa Nl Wong, Michael D. Cheetham, David Morand

Southern Cross GeoScience

No abstract provided.


Functionalization Of Multi-Walled Carbon Nanotubes In Epoxy Composites, Chris Fitzwater 2010 University of Kentucky

Functionalization Of Multi-Walled Carbon Nanotubes In Epoxy Composites, Chris Fitzwater

University of Kentucky Master's Theses

Multi-walled carbon nanotubes (MWNTs) are a relatively new allotrope of carbon that have potentially useful properties that may improve polymer composites. The work of this thesis explores the interactions between MWNTs and functionalized MWNTs within epoxy matrix and the properties of the MWNT/epoxy composite. These interactions were characterized with an emphasis on finding how well the MWNT/epoxy composite flows and how conductive it is after curing.


Latest Quaternary Paleoclimate Reconstruction Utilizing Stable Isotopic And Trace Element Proxies In A Stalagmite From Culverson Creek Cave, West Virginia, Ashley Nicole Gilbert 2010 University of Kentucky

Latest Quaternary Paleoclimate Reconstruction Utilizing Stable Isotopic And Trace Element Proxies In A Stalagmite From Culverson Creek Cave, West Virginia, Ashley Nicole Gilbert

University of Kentucky Master's Theses

A reconstruction of regional climate variability in southern West Virginia that spans the last glacial/interglacial transition is presented. Paleoclimate interpretations obtained from the 50-cm long stalagmite provide key insights regarding the timing, magnitude, and forcing mechanisms responsible for past climate variability. Stable isotopic (δ18O and δ13C) and trace element (Ba, Sr, Mg) signatures from samples contiguously milled along the growth-axis of a 230Th-dated stalagmite which grew between approximately 20 and 5 thousand years before present (kyr BP) provide critical constraints for above-cave mean annual temperature, seasonality of moisture mean annual precipitation, and potential vegetation ...


On The Accuracy Of Explicit Finite-Volume Schemes For Fluctuating Hydrodynamics, Aleksandar Donev, Eric Vanden-Eijnden, Alejandro Garcia, John B. Bell 2010 Lawrence Livermore National Laboratory

On The Accuracy Of Explicit Finite-Volume Schemes For Fluctuating Hydrodynamics, Aleksandar Donev, Eric Vanden-Eijnden, Alejandro Garcia, John B. Bell

Alejandro Garcia

This paper describes the development and analysis of finite-volume methods for the Landau–Lifshitz Navier–Stokes (LLNS) equations and related stochastic partial differential equations in fluid dynamics. The LLNS equations incorporate thermal fluctuations into macroscopic hydrodynamics by the addition of white noise fluxes whose magnitudes are set by a fluctuation-dissipation relation. Originally derived for equilibrium fluctuations, the LLNS equations have also been shown to be accurate for nonequilibrium systems. Previous studies of numerical methods for the LLNS equations focused primarily on measuring variances and correlations computed at equilibrium and for selected nonequilibrium flows. In this paper, we introduce a more ...


Coarsening In High Order, Discrete, Ill-Posed Diffusion Equations, Catherine Kublik 2010 University of Dayton

Coarsening In High Order, Discrete, Ill-Posed Diffusion Equations, Catherine Kublik

Mathematics Faculty Publications

We study the discrete version of a family of ill-posed, nonlinear diffusion equations of order 2n. The fourth order (n=2) version of these equations constitutes our main motivation, as it appears prominently in image processing and computer vision literature. It was proposed by You and Kaveh as a model for denoising images while maintaining sharp object boundaries (edges). The second order equation (n=1) corresponds to another famous model from image processing, namely Perona and Malik's anisotropic diffusion, and was studied in earlier papers. The equations studied in this paper are high order analogues of the Perona-Malik equation ...


Periodic Solutions Of Neutral Delay Integral Equations Of Advanced Type, Muhammad Islam, Nasrin Sultana, James Booth 2010 University of Dayton

Periodic Solutions Of Neutral Delay Integral Equations Of Advanced Type, Muhammad Islam, Nasrin Sultana, James Booth

Mathematics Faculty Publications

We study the existence of continuous periodic solutions of a neutral delay integral equation of advanced type. In the analysis we employ three fixed point theorems: Banach, Krasnosel'skii, and Krasnosel'skii-Schaefer. Krasnosel'skii-Schaefer fixed point theorem requires an a priori bound on all solutions. We employ a Liapunov type method to obtain such bound.


Formalization Of The Ad Hominem Argumentation Scheme, Douglas Walton 2010 University of Windsor

Formalization Of The Ad Hominem Argumentation Scheme, Douglas Walton

CRRAR Publications

In this paper, several examples from the literature, and one central new one, are used as case studies of texts of discourse containing an argumentation scheme that has now been widely investigated in literature on argumentation. Argumentation schemes represent common patterns of reasoning used in everyday conversational discourse. The most typical ones represent defeasible arguments based on nonmonotonic reasoning. Each scheme has a matching set of critical questions used to evaluate a particular argument fitting that scheme. The project is to study how to build a formal computational model of this scheme for the circumstantial ad hominem argument using argumentation ...


Hydroacoustic Survey And Point Sampling Of Macrophytes In Diamond Lake 2009, Joseph Eilers, Benn Eilers, Mark D. Sytsma, Rich Miller 2010 Portland State University

Hydroacoustic Survey And Point Sampling Of Macrophytes In Diamond Lake 2009, Joseph Eilers, Benn Eilers, Mark D. Sytsma, Rich Miller

Center for Lakes and Reservoirs Publications and Presentations

MaxDepth Aquatics, Inc. was contracted to conduct a hydroacoustic survey of macrophyte distribution in Diamond Lake in 2009. The survey essentially repeated surveys conducted in 2002 and 2007, allowing for a detailed assessment of conditions in 2009 and comparisons among previous years. In addition, Portland State University was contracted to conduct a depth stratified random point sample survey of macrophyte species presence and absence. The point sample survey was similar to surveys conducted in 2005 and 2007. The results of the 2009 hydroacoustic survey showed that macrophytes were widely distributed throughout the lake at depths less than 8 meters, although ...


A Reasonable Semantic Web, Pascal Hitzler, Frank van Harmelen 2010 Wright State University - Main Campus

A Reasonable Semantic Web, Pascal Hitzler, Frank Van Harmelen

Computer Science and Engineering Faculty Publications

The realization of Semantic Web reasoning is central to substantiating the Semantic Web vision. However, current mainstream research on this topic faces serious challenges, which forces us to question established lines of research and to rethink the underlying approaches. We argue that reasoning for the Semantic Web should be understood as "shared inference," which is not necessarily based on deductive methods. Model-theoretic semantics (and sound and complete reasoning based on it) functions as a gold standard, but applications dealing with large-scale and noisy data usually cannot afford the required runtimes. Approximate methods, including deductive ones, but also approaches based on ...


Distributed Reasoning With El++ Using Mapreduce, Frederick Maier, Raghava Mutharaju, Pascal Hitzler 2010 Wright State University - Main Campus

Distributed Reasoning With El++ Using Mapreduce, Frederick Maier, Raghava Mutharaju, Pascal Hitzler

Computer Science and Engineering Faculty Publications

It has recently been shown that the MapReduce framework for distributed computation can be used effectively for large-scale RDF Schema reasoning, computing the deductive closure of over a billion RDF triples within a reasonable time. Later work has carried this approach over to OWL Horst. In this paper, we provide a MapReduce algorithm for classifying knowledge bases in the description logic EL++, which is essentially the OWL 2 profile OWL 2 EL. The traditional EL++ classification algorithm is recast into a form compatible with MapReduce, and it is shown how the revised algorithm can be realized within the MapReduce framework ...


Approximate Instance Retrieval On Ontologies, Tuvshintur Tserendorj, Stephan Grimm, Pascal Hitzler 2010 Wright State University - Main Campus

Approximate Instance Retrieval On Ontologies, Tuvshintur Tserendorj, Stephan Grimm, Pascal Hitzler

Computer Science and Engineering Faculty Publications

With the development of more expressive description logics (DLs) for the Web Ontology Language OWL the question arises how we can properly deal with the high computational complexity for efficient reasoning. In application cases that require scalable reasoning with expressive ontologies, non-standard reasoning solutions such as approximate reasoning are necessary to tackle the intractability of reasoning in expressive DLs. In this paper, we are concerned with the approximation of the reasoning task of instance retrieval on DL knowledge bases, trading correctness of retrieval results for gain of speed. We introduce our notion of an approximate concept extension and we provide ...


A Database Server For Next-Generation Scientific Data Management, Mohamed Eltabakh, Walid G. Aref, Ahmed Elmagarmid 2010 Purdue University

A Database Server For Next-Generation Scientific Data Management, Mohamed Eltabakh, Walid G. Aref, Ahmed Elmagarmid

Cyber Center Publications

The growth of scientific information and the increasing automation of data collection have made databases integral to many scientific disciplines including life sciences, physics, meteorology, earth and atmospheric sciences, and chemistry. These sciences pose new data management challenges to current database system technologies. This dissertation addresses the following three challenges: (1) Annotation Management: Annotations and provenance information are important metadata that go hand-in-hand with scientific data. Annotating scientific data represents a vital mechanism for scientists to share knowledge and build an interactive and collaborative environment. A major challenge is: How to manage large volumes of annotations, especially at various granularities ...


Spatio-Temporal Access Methods: Part 2 (2003 - 2010), Long-Van Nguyen-Dinh, Walid G. Aref, Mohamed Mokbel 2010 Purdue University

Spatio-Temporal Access Methods: Part 2 (2003 - 2010), Long-Van Nguyen-Dinh, Walid G. Aref, Mohamed Mokbel

Cyber Center Publications

In spatio-temporal applications, moving objects detect their locations via location-aware devices and update their locations continuously to the server. With the ubiquity and massive numbers of moving objects, many spatio-temporal access methods are developed to process user queries efficiently. Spatio- temporal access methods are classified into four categories: (1) Indexing the past data, (2) Indexing the current data, (3) Indexing the future data, and (4) Indexing data at all points of time. This short survey is Part 2 of our previous work [28]. In Part 2, we give an overview and classification of spatio-temporal access methods that are published between ...


The Dynamic X-Ray Sky Of The Local Universe, S. Boggs, C. Wunderer, P. von Ballmoos, T. Takahashi, N. Gehrels, J. Tueller, M. Baring, J. Beacom, R. Diehl, Dieter H. Hartmann 2010 Space Sciences Laboratory, University of California, Berkeley

The Dynamic X-Ray Sky Of The Local Universe, S. Boggs, C. Wunderer, P. Von Ballmoos, T. Takahashi, N. Gehrels, J. Tueller, M. Baring, J. Beacom, R. Diehl, Dieter H. Hartmann

Publications

Over the next decade, we can expect time domain astronomy to flourish at optical and radio wavelengths. In parallel with these efforts, a dedicated transient "machine" operating at higher energies (X-ray band through soft gamma-rays) is required to reveal the unique subset of events with variable emission predominantly visible above 100 eV. Here we focus on the transient phase space never yet sampled due to the lack of a sensitive, wide-field and triggering facility dedicated exclusively to catching high energy transients and enabling rapid coordinated multi-wavelength follow-up. We first describe the advancements in our understanding of known X-ray transients that ...


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