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Vibrational Spectroscopy and X-ray Diffraction of Cd(OH)2 to 28GPa at 300 K

Description: We report Raman and infrared absorption spectroscopy alongwith X-ray diffraction for brucite-type beta-Cd(OH)2 to 28 GPa at 300 K.The OH-stretching modes soften with pressure and disappear at 21 GPa withtheir widths increasing rapidly above 5 GPa, consistent with a gradualdisordering of the H sublattice at 5 20 GPa similar to that previouslyobserved for Co(OH)2.Asymmetry in the peak shapes of the OH-stretchingmodes suggests the existence of diverse disordered sitesfor H atoms inCd(OH)2 under pr… more
Date: March 20, 2006
Creator: Shim, Sang-Heon; Rekhi, Sandeep; Martin, Michael C. & Jeanloz,Raymond
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reversible Guest Exchange Mechanisms in Supramolecular Host-Guest Assemblies

Description: Synthetic chemists have provided a wide array of supramolecular assemblies able to encapsulate guest molecules. The scope of this tutorial review focuses on supramolecular host molecules capable of reversibly encapsulating polyatomic guests. Much work has been done to determine the mechanism of guest encapsulation and guest release. This review covers common methods of monitoring and characterizing guest exchange such as NMR, UV-VIS, mass spectroscopy, electrochemistry, and calorimetry and also… more
Date: September 1, 2006
Creator: Pluth, Michael D. & Raymond, Kenneth N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Education and Outreach Project of ATLAS - A New Participant inPhysics Education

Description: The ATLAS experiment at the Large Hadron Collider at CERN has a substantial collaborative Education and Outreach project. This article describes its activities and how it promotes physics to students around the world. With the extraordinary possibility to make groundbreaking discoveries, the ATLAS Experiment [1] at the Large Hadron Collider at CERN can play an important role in promoting contemporary physics at school. For many years ATLAS has had a substantial collaborative Education and Outre… more
Date: April 15, 2006
Creator: Barnett, R. Michael & Johansson, K. Erik
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Partner: UNT Libraries Government Documents Department
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Quantum Mechanical Single Molecule Partition Function from Path Integral Monte Carlo Simulations

Description: An algorithm for calculating the partition function of a molecule with the path integral Monte Carlo method is presented. Staged thermodynamic perturbation with respect to a reference harmonic potential is utilized to evaluate the ratio of partition functions. Parallel tempering and a new Monte Carlo estimator for the ratio of partition functions are implemented here to achieve well converged simulations that give an accuracy of 0.04 kcal/mol in the reported free energies. The method is applied… more
Date: October 1, 2006
Creator: Chempath, Shaji; Bell, Alexis T. & Predescu, Cristian
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studying High pT muons in Cosmic-Ray Air Showers

Description: Most cosmic-ray air shower arrays have focused on detectingelectromagnetic shower particles and low energy muons. A few groups (mostnotably MACRO + EASTOP and SPASE + AMANDA) have studied the high energymuon component of showers. However, these experiments had small solidangles, and did not study muons far from the core. The IceTop + IceCubecombination, with its 1 km$^2$ muon detection area can study muons farfrom the shower core. IceCube can measure their energy loss ($dE/dx$),and hence their … more
Date: December 1, 2006
Creator: Klein, Spencer R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complete chloroplast genome of Trachelium caeruleum: extensiverearrangements are associated with repeats and tRNAs

Description: Chloroplast genome structure, gene order and content arehighly conserved in land plants. We sequenced the complete chloroplastgenome sequence of Trachelium caeruleum (Campanulaceae) a member of anangiosperm family known for highly rearranged chloroplast genomes. Thetotal genome size is 162,321 bp with an IR of 27,273 bp, LSC of 100,113bp and SSC of 7,661 bp. The genome encodes 115 unique genes, with 19duplicated in the IR, a tRNA (trnI-CAU) duplicated once in the LSC and aprotein coding gene (p… more
Date: January 9, 2006
Creator: Haberle, Rosemarie C.; Fourcade, Matthew L.; Boore, Jeffrey L. & Jansen, Robert K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of Order Formation in Block Copolymer Thin Films UsingResonant Soft X-Ray Scattering

Description: The lateral order of poly(styrene-block-isoprene) copolymer(PS-b-PI) thin films is characterized by the emerging technique ofresonant soft X-ray scattering (RSOXS) at the carbon K edge and comparedto ordering in bulk samples of the same materials measured usingconventional small-angle X-ray scattering. We show resonance using theoryand experiment that the loss of scattering intensity expected with adecrease in sample volume in the case of thin films can be overcome bytuning X-rays to the pi* re… more
Date: November 27, 2006
Creator: Virgili, Justin M.; Tao, Yuefei; Kortright, Jeffrey B.; Balsara,Nitash P. & Segalman, Rachel A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Revealing Charge Density Wave Formation in the LaTe2 System byAngle Resolved Photoemission Spectroscopy

Description: We present the first direct study of charge density wave(CDW) formation in quasi-2D single layer LaTe2 using high-resolutionangle resolved photoemission spectroscopy (ARPES) and low energy electrondiffraction (LEED). CDW formation is driven by Fermi surface (FS)nesting, however characterized by a surprisingly smaller gap (~;50 meV)than seen in the double layer RTe3 compounds, extending over the entireFS. This establishes LaTe2 as the first reported semiconducting 2D CDWsystem where the CDW phas… more
Date: November 15, 2006
Creator: Garcia, D. R.; Gweon, G.-H.; Zhou, S. Y.; Graf, J.; Jozwiak, C. M.; Jung, M. H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fishing for biodiversity: Novel methanopterin-linked C1 transfergenes deduced from the Sargasso Sea metagenome

Description: The recently generated database of microbial genes from anoligotrophic environment populated by a calculated 1,800 of major phylotypes (the Sargasso Sea metagenome) presents a great source for expanding local databases of genes indicative of a specific function. In this paper we analyze the Sargasso Sea metagenome in terms of the presence of methanopterin-linked C1 transfer genes that are signature for methylotrophy. We conclude that more than 10 phylotypes possessing genes of interest are pres… more
Date: July 1, 2004
Creator: Kalyuzhnaya, Marina G.; Nercessian, Olivier; Lapidus, Alla & Chistoserdova, Ludmila
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complete chloroplast genome sequences of Drimys, Liriodendron, andPiper: Implications for the phylogeny of magnoliids and the evolution ofGC content

Description: The magnoliids represent the largest basal angiosperm clade with four orders, 19 families and 8,500 species. Although several recent angiosperm molecular phylogenies have supported the monophyly of magnoliids and suggested relationships among the orders, the limited number of genes examined resulted in only weak support, and these issues remain controversial. Furthermore, considerable incongruence has resulted in phylogenies supporting three different sets of relationships among magnoliids and … more
Date: June 1, 2006
Creator: Zhengqiu, C.; Penaflor, C.; Kuehl, J.V.; Leebens-Mack, J.; Carlson, J.; dePamphilis, C.W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coral Reef Genomics: Developing tools for functional genomics ofcoral symbiosis

Description: Symbioses between cnidarians and dinoflagellates in the genus Symbiodinium are widespread in the marine environment. The importance of this symbiosis to reef-building corals and reef nutrient and carbon cycles is well documented, but little is known about the mechanisms by which the partners establish and regulate the symbiosis. Because the dinoflagellate symbionts live inside the cells of their host coral, the interactions between the partners occur on cellular and molecular levels, as each pa… more
Date: March 1, 2005
Creator: Schwarz, Jodi; Brokstein, Peter; Manohar, Chitra; Coffroth, MaryAlice; Szmant, Alina & Medina, Monica
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A phylogenomic gene cluster resource: The phylogeneticallyinferred groups (PhlGs) database

Description: We present here the PhIGs database, a phylogenomic resource for sequenced genomes. Although many methods exist for clustering gene families, very few attempt to create truly orthologous clusters sharing descent from a single ancestral gene across a range of evolutionary depths. Although these non-phylogenetic gene family clusters have been used broadly for gene annotation, errors are known to be introduced by the artifactual association of slowly evolving paralogs and lack of annotation for tho… more
Date: August 25, 2005
Creator: Dehal, Paramvir S. & Boore, Jeffrey L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Type IIP supernovae as cosmological probes: A SEAM distance to SN1999em

Description: Because of their intrinsic brightness, supernovae make excellent cosmological probes. We describe the spectral-fitting expanding atmosphere method (SEAM) for obtaining distances to Type IIP supernovae (SNe IIP) and present a distance to SN 1999em for which a Cepheid distance exists. Our models give results consistent with the Cepheid distance, even though we have not attempted to tune the underlying hydrodynamical model but have simply chosen the best fits. This is in contradistinction to the e… more
Date: June 1, 2004
Creator: Baron, E.; Nugent, Peter E.; Branch, David & Hauschildt, Peter H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Imaging of InGaN inhomogeneities using visible aperturelessnear-field scanning optical microscope

Description: The optical properties of epitaxially grown islands of InGaN are investigated with nanometer-scale spatial resolution using visible apertureless near-field scanning optical microscopy. Scattered light from the tip-sample system is modulated by cantilever oscillations and detected at the third harmonic of the oscillation frequency to distinguish the near-field signal from unwanted scattered background light. Scattered near-field measurements indicate that the as-grown InGaN islanded film may exh… more
Date: June 14, 2007
Creator: Stebounova, Larissa V.; Romanyuk, Yaroslav E.; Chen, Dongxue & Leone, Stephen R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Acid Catalysis in Basic Solution: A Supramolecular Host PromotesOrthoformate Hydrolysis

Description: Though many enzymes can promote chemical reactions by tuning substrate properties purely through the electrostatic environment of a docking cavity, this strategy has proven challenging to mimic in synthetic host-guest systems. Here we report a highly-charged, water soluble, metal-ligand assembly with a hydrophobic interior cavity that thermodynamically stabilizes protonated substrates and consequently catalyzes the normally acidic hydrolysis of orthoformates in basic solution, with rate acceler… more
Date: December 12, 2007
Creator: Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Requirements and standards for organelle genome databases

Description: Mitochondria and plastids (collectively called organelles)descended from prokaryotes that adopted an intracellular, endosymbioticlifestyle within early eukaryotes. Comparisons of their remnant genomesaddress a wide variety of biological questions, especially when includingthe genomes of their prokaryotic relatives and the many genes transferredto the eukaryotic nucleus during the transitions from endosymbiont toorganelle. The pace of producing complete organellar genome sequences nowmakes it un… more
Date: January 9, 2006
Creator: Boore, Jeffrey L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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How to Find More Supernovae with Less Work: Object ClassificationTechniques for Difference Imaging

Description: We present the results of applying new object classificationtechniques to difference images in the context of the Nearby SupernovaFactory supernova search. Most current supernova searches subtractreference images from new images, identify objects in these differenceimages, and apply simple threshold cuts on parameters such as statisticalsignificance, shape, and motionto reject objects such as cosmic rays,asteroids, and subtraction artifacts. Although most static objectssubtract cleanly, even a … more
Date: May 2, 2007
Creator: Bailey, Stephen; Aragon, Cecilia; Romano, Raquel; Thomas, RollinC.; Weaver, Benjamin A. & Wong, Daniel
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Probing the band structure of LaTe2 using angle resolved photoemission spectroscopy

Description: With the current interest in the rare-earth tellurides ashigh temperature charge density wave materials, a greater understandingof the physics of these systems is needed, particularly in the case ofthe ditellurides. We report a detailed study of the band structure ofLaTe_2 in the charge density wave state using high-resolution angleresolved photoemission spectroscopy (ARPES). From thiswork we hope toprovide insights into the successes and weaknesses of past theoreticalstudy as well as helping t… more
Date: November 1, 2006
Creator: Garcia, Daniel R.; Zhou, Shuyun Y.; Gweon, Gey-Hong; Jung, M.H.; Kwon, Y.S. & Lanzara, Alessandra
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Making Amines Strong Bases: Thermodynamic Stabilization ofProtonated Guests in a Highly-Charged Supramolecular Host

Description: A highly-charged, cavity-containing supramolecular assembly formed by metal-ligand interactions acts as a host to dramatically shift the effective basicity of encapsulated protonated amine guests. The scope of encapsulated protonated amine and phosphine guests shows size selectivity consistent with a constrained binding environment. Protonation of the encapsulated guests is confirmed by {sup 31}P NMR studies, mass spectrometry studies, and the pH dependence of guest encapsulation. Rates of gues… more
Date: April 16, 2007
Creator: Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Insertion of a self-splicing intron into the mtDNA of atriploblastic animal

Description: Nephtys longosetosa is a carnivorous polychaete worm that lives in the intertidal and subtidal zones with worldwide distribution (pleijel&rouse2001). Its mitochondrial genome has the characteristics typical of most metazoans: 37 genes; circular molecule; almost no intergenic sequence; and no significant gene rearrangements when compared to other annelid mtDNAs (booremoritz19981995). Ubiquitous features as small intergenic regions and lack of introns suggested that metazoan mtDNAs are under … more
Date: April 14, 2006
Creator: Valles, Y.; Halanych, K. & Boore, J.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Excited State Structural Dynamics of Carotenoids and ChargeTransfer Systems

Description: This dissertation describes the development andimplementation of a visible/near infrared pump/mid-infrared probeapparatus. Chapter 1 describes the background and motivation ofinvestigating optically induced structural dynamics, paying specificattention to solvation and the excitation selection rules of highlysymmetric molecules such as carotenoids. Chapter 2 describes thedevelopment and construction of the experimental apparatus usedthroughout the remainder of this dissertation. Chapter 3 will … more
Date: September 1, 2006
Creator: Van Tassle, Aaron Justin
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Benefits of IEEE-754 features in modern symmetric tridiagonaleigensolvers

Description: Bisection is one of the most common methods used to compute the eigenvalues of symmetric tridiagonal matrices. Bisection relies on the Sturm count: For a given shift a, the number of negative pivots in the factorization T - {sigma}I = LDL{sup T} equals the number of eigenvalues of T that are smaller than a. In IEEE-754 arithmetic, the value oo permits the computation to continue past a zero pivot, producing a correct Sturm count when T is unreduced. Demmel and Li showed that using oo rather tha… more
Date: March 12, 2006
Creator: Marques, Osni; Riedy, Jason E. & Vomel, Christof
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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