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CreatorTitleDescriptionSubjectDate
376 Miller, Joel StevenFormation of a zwitterionic donor-acceptor compound based on N,N,N',N'-tetramethly-p-phenylenediamine and 7,7,8,8-tetracyanoperfluoro-p-quinodimethaneThe reaction of the donor N,N,N',N'- tetramethyl-p-phenylenediamine (TMPD) with the acceptor 7,7,8,8-tetracyanoperfluoro-p-quinodimethane (TCNQF4) has led to the isolation of a novel type of zwitterionic donor-acceptor compound whose structure has been determined by X-ray crystallography.Ccrystals; Single bond1988
377 DeTar, CarletonHigh-precision lattice QCD confronts experimentThe recently developed Symanzik-improved staggered-quark discretization allows unquenched lattice-QCD simulations with much smaller (and more realistic) quark masses than previously possible. To test this formalism, we compare experiment with a variety of nonperturbative calculations in QCD draw...Staggered quarks2004-01
378 Mattis, Daniel C.Tricritical point in random-field Ising modelThe numerical investigation of the random-field Ising model by Houghton, Khurana, and Seco1 has revealed a number of interesting features concerning the three-dimensional Ising model in a random external field Bt. Earlier, Aharony2 had already found that even in a mean-field approximation the b...Random external field; Tricritical points; Gaussian distribution1985
379 Vardeny, Zeev Valentine; Nahata, AjayThermal emission from metallic films perforated with subwavelength hole arraysThis report presents an overview of our study on the optical transmission and thermal light emission properties of subwavelength hole arrays fabricated in a square lattice with 4 um periodicity. The structures were fabricated in thin aluminum (Al) films on silicon (Si) substrates using conventional ...2008
380 Olivera, Baldomero M.?O-Conotoxins inhibit NaV channels by interfering with their voltage sensors in domain-2The ?O-conotoxins MrVIA and MrVIB are 31-residue peptides from Conus marmoreus, belonging to the O-superfamily of conotoxins with three disulfide bridges. They have attracted attention because they are inhibitors of tetrodotoxin-insensitive voltage-gated sodium channels (NaV1.8) and could therefore ...2007
381 Thomas, Kirk R.; Capecchi, Mario R.Maintenance of functional equivalence during paralogous Hox gene evolution.Biological diversity is driven mainly by gene duplication followed by mutation and selection. This divergence in either regulatory or protein-coding sequences can result in quite different biological functions for even closely related genes. This concept is exemplified by the mammalian Hox gene comp...Alleles; Animals; Cervical Vertebrae; Embryo; Genetic Complementation Test; Homeodomain Proteins; Homozygote; Mice2000-02-10
382 Gondolo, PaoloCosmic ray positron excess and neutralino dark matterUsing a new instrument, the HEAT Collaboration has confirmed the excess of cosmic ray positrons that they first detected in 1994. We explore the possibility that this excess is due to the annihilation of neutralino dark matter in the galactic halo. We confirm that neutralino annihilation can produ...Neutralinos; Supersymmetric models; Positron flux; Annihilations2002-02
383 Bohs, Lynn A.Phylogeny and biogeography of the Canarian Solanum vespertilio and S. lidii (Solanaceae)The endemic and rare Solanum vespertilio and S. lidii from the Canary Islands are notable in being andromonoecious, self compatible, highly heterandrous (with short >reward= anthers and one very long >pollination= anther), and bearing strongly zygomorphic corollas. Solanum vespertilio flowers are a...Solanum vespertilio; Solanum lidii; Leptostemonum; tnT-F region; granule-bound starch synthase gene; GBSSI; Andromonoecy; Hererandry; Enantiostyly2006
384 Capecchi, Mario R.Personal view of gene targetingGene targeting provides the means for creating strains of mice with mutations in virtually any gene.1 First, the desired mutation is introduced into a cloned copy of the chosen gene by standard recombinant DNA technology. The mutation is then transferred to the genome of a pluripotent mouse embryo-d...1995
385 DeTar, CarletonHadronic deformation energy. I. Quark-antiquark separationThe MIT bag model for hadrons is treated in the static cavity approximation in three dimensions with a definite quark number. The energy of the system is computed to second order in the gluon coupling. A constrained variational method is described which permits the calculation of the energy as a f...Bag models; Quark bag; Deformation energy; Antiquarks; Gluon coupling; Quark energies; Gluon energies1978-01
386 Capecchi, Mario R.Characterization of three proteins involved in polypeptide chain termination.At each stage of elongation, the growing polypeptide chain is bound to the ribosome-messenger RNA complex through the transfer RNA of the most recently incorporated amino acid residue. When the chain is complete, the last polypeptide-transfer RNA (tuna) ester linkage is cleaved, releasing the chain ...Anti-Bacterial Agents; Phenylalanine; Stimulation, Chemical1969
387 Ailion, David Charles109Ag NMR investigation of atomic motions in the incommensurate and paraelectric phases of proustite (Ag3AsS3)109Ag NMR line shape, T1 , Hahn spin echo, and Carr-Purcell-Meiboom-Gill ~CPMG! spin-echo measurements were performed in proustite (Ag3AsS3) between 420 and 47 K in order to understand the role of atomic motions in phase transitions in a system containing an incommensurate phase. These measurements ...NMR; Atomic motion; Proustitie; Phase transitions; Line shape2000
388 Voth, Gregory AlanMultiscale coarse-graining of the protein energy landscapeA variety of coarse-grained (CG) models exists for simulation of proteins. An outstanding problem is the construction of a CG model with physically accurate conformational energetics rivaling all-atom force fields. In the present work, atomistic simulations of peptide folding and aggregation equilib...2010-06-24
389 Miller, Joel StevenFerrimagnetic ordering of one-dimensional N,N'-dicyanoquinone diimine (DCNQI) electron transfer salts with porphyrinatomanganese(II)*The redox reaction between N,N'-dicyanoquinone diimines (DCNQIs) and porphyrinatomanganese(II) produced electron transfer salts (ETSs), [MnIIITMesP]+[DMeO-DCNQI]-. 1 (MnIIITMesP=meso-tetrakis(2,4,6- trimethylphenyl)porphyrinatomanganese(III), DMeO-DCNQI=2,5-dimethoxy-N,N'-dicyanoquinone diimine) an...Transitions; Interactions; Magnetic2001
390 Thomas, Kirk R.; Capecchi, Mario R.High-fidelity gene targeting in embryonic stem cells by using sequence replacement vectors.Mutations were targeted to the Hprt locus in murine embryonic stem cells by using sequence replacement vectors. When the vector was designed such that the mutated sequences were flanked on both sides by several kilobases of DNA homologous to the target locus, replacement of chromosomal sequences wit...Drug Resistance; Gene Rearrangement; Gentamicins1992-07
391 DeTar, CarletonEquation of state and QCD transition at finite temperatureWe calculate the equation of state in 2 + 1 flavor QCD at finite temperature with physical strange quark mass and almost physical light quark masses using lattices with temporal extent Nr = 8. Calculations have been performed with two different improved staggered fermion actions, the asqtad and p4 a...Deconfinement; Chiral symmetry; Staggered fermions; Phase transitions; Polyakov loop2009-07
392 Coley, Phyllis D.Benefits and costs of defense in a neotropical shrubBenefits and costs are central to optimality theories of plant defense. Benefit is the gain in fitness to reducing herbivory and cost is the loss in fitness to committing resources to defense. We evaluate the benefits and costs of defense in a neotropical shrub, Psychotria horizontalis. Plants were ...Cost of defense; Growth-defense trade-off; Exclosures; Field experiment; Herbivory; Panama; Psychotria horizontalis; Rubiaceae; Tannins; Toughness; Tropics1995
393 Wu, Yong-ShiMultiparticle quantum mechanics obeying fractional statisticsWe obtain the rule governing many-body wave functions for particles obeying fractional statistics in two (space) dimensions. It generalizes and continuously interpolates the usual symmetrization and antisymmetrization. Quantum mechanics of more than two particles is discussed and some new features a...Multiparticle quantum mechanics; Fractional statistics1984-07
394 Miller, Joel StevenFar-infrared powder spectrum of (N(CH3)3D)(I)(TCNQ)We present the powder absorption spectrum of (TMA)(I)(TCNQ) in the far-infrared as a function of temperature. Below 160 K new absorption features appear and others increase in intensity. This behaviour supports the electron- neutron-diffraction evidence of a distortion on the TCNQ chains below the f...Conductivity, Crystals, Electrons1983
395 Beckerle, Mary C.Kindler syndrome protein is regulated by Transforming Growth Factor-β and involved in integrin-mediated adhesionTransforming growth factor-β1 (TGF-β1) contributes to tumor invasion and cancer progression by increasing the motility of tumor cells. To identify genes involved in TGF-β-mediated cell migration, the transcriptional profiles of human mammary epithelial cells (HMEC) treated with TGF-β were compar...Kindler syndrome; Kindlerin; Talin; Focal adhesions; FERM domain2004
396 Rogachev, AndreyEnhancing superconductivity: magnetic impurities and their quenching by magnetic fieldsMagnetic fields and magnetic impurities are each known to suppress superconductivity. However, as the field quenches (i.e. polarizes) the impurities, rich consequences, including field-enhanced superconductivity, can emerge when both effects are present. For the case of superconducting wires and th...Thermal phase slippage; Coulomb blockade2006-09-01
397 Vardeny, Zeev ValentineExcitation dynamics in single molecular crystals of α-hexathiophene from femtosecond to millisecondWe identify odd- and even-parity states and measure transient photomodulation spectra of Frenkel excitons in a-hexathiophene single crystals. The lowest Frenkel excitons are characterized by a stimulated emission band at ~2 eV and an absorption band at 1.3 eV. Intramolecular internal conversion go...Excitation dynamics; alpha-hexathiophene; Frenkel excitons; pi-conjugated polymers; Photoexcitation2001-04
398 Vardeny, Zeev ValentineLasing and stimulated emission in ∏-conjugated polymersRecent studies of lasing and stimulated emission in luminescent -conjugated polymers performed by our group are presented. Optical properties of cylindrical high- polymer microcavities are discussed. The emission spectra of plastic microring and microdisk lasers are measured and analyzed. Light-emi...Lasing; Stimulated emission; pi-conjugated polymers; Microcavities; Polymer lasers2000-01
399 Sokolsky, PierreBackward production in π-p→pπ+π-π- at 8 GeV/c*We have studied backward baryon and meson production in π'p → pπ+pπ +π-π- at 8.0 GeV/c using a streamer chamber triggered by the detection of a fast forward proton. Our data sample (1227 events) displays prominent N*p and N*f quasi-two-body production. These states are investigated with rega...1976-01
400 Capecchi, Mario R.Mice lacking endothelial ACE: normal blood pressure with elevated angiotensin IIRecently, the concept of local renin-angiotensin systems (RAS) capable of generating angiotensin II apart from the circulation has received considerable attention. To investigate this, we generated ACE 1/3 mice in which one allele of ACE is null and the second allele was engineered to express ACE o...2003
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