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CreatorTitleDescriptionSubjectDate
1 Poulter, Charles Dale(S)-Geranylgeranylglyceryl phosphate synthase. Purification and characterization of the first pathway-specific enzyme in archaebacterial membrane lipid biosynthesisThe first pathway-specific step in the biosynthesis of the core membrane diether lipids in archaebacteria is the alkylation of the primary hydroxyl group in (S)-glyceryl phosphate by geranylgeranyl diphosphate. The reaction is catalyzed by (S)-3-O-geranylgeranylglyceryl phosphate ((S)-GGGP) synthase...Polyacrylamide gel; Molecular weight1993-10-15
2 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
3 Ailion, David Charles14N study of the role of N-D---O bonds in the deuteron glass transition14N spin-lattice relaxation-time measurements in Rb0.28(ND4)0.72D2PO4 provide direct evidence for the fast exchange averaging of the "long" and "short" N-D---O hydrogen bonds between the ND4 group and the four surrounding PO4 groups. This exchange and the associated distortion of the ND4 tetrahedron...NMR; Hydrogen bonds; Spin-lattice; Relaxation-time; Deuteron glass1999
4 Poulter, Charles Dale; Davis, Darrell R.15N labeled e. coli tRNAMet, tRNAGlu, tRNATyr, and tRNAPhe. Double resonance and two dimensional NMR of H-N1 units in pseudouridineThe N1 imino units in Escherichia coli tRNAfMet, tRNAGlu, tRNAPhe, and tRNATyr were studied by 1H-15N NMR using three different techniques to suppress signals of protons not attached to 15N. Two of the procedures, Fourier internuclear difference spectroscopy and two-dimensional forbidden echo spectr...Escherichia coli; Magnetic resonance spectroscopy; Nucleic acid conformation1985-08-15
5 Poulter, Charles Dale; Davis, Darrell R.15N-labeled Escherichia coli tRNAfMet, tRNAGlu, tRNATyr, and tRNAPhe. Double resonance and two-dimensional NMR of N1-labeled pseudouridine.The N1 imino units in Escherichia coli tRNAfMet, tRNAGlu, tRNAPhe, and tRNATyr were studied by 1H-15N NMR using three different techniques to suppress signals of protons not attached to 15N. Two of the procedures, Fourier internuclear difference spectroscopy and two-dimensional forbidden echo spectr...Escherichia coli; Magnetic resonance spectroscopy; Nitrogen; Nucleic acid conformation1985-08-15
6 Poulter, Charles Dale; Davis, Darrell R.15N-labeled tRNA. Identification of 4-thiouridine in Escherichia coli tRNASer1 and tRNATyr2 by 1H-15N two-dimensional NMR spectroscopy.Uridine is uniquely conserved at position 8 in elongator tRNAs and binds to A14 to form a reversed Hoogsteen base pair which folds the dihydrouridine loop back into the core of the L-shaped molecule. On the basis of 1H NMR studies, Hurd and co-workers (Hurd, R. E., Robillard, G. T., and Reid, B. R. ...Magnetic resonance spectroscopy1986-09-15
7 Poulter, Charles Dale; Davis, Darrell R.15N-labeled tRNA. Identification of dihydrouridine in Escherichia coli tRNAfMet, tRNALys, and tRNAPhe by 1H-15N two-dimensional NMR.The N3 imino units of dihydrouridine were identified in samples of 15N-labeled Escherichia coli tRNAfMet, tRNALys, and tRNAPhe by 1H-15N two-dimensional NMR. The peaks for dihydrouridine had high field 1H (9.7-9.8 ppm) and 15N (147.8-149.5 ppm) chemical shifts. Assignments were made by 1H-15N chemic...Hydrogen Bonding; Magnetic Resonance Spectroscopy; Magnetic Resonance Spectroscopy1986-03-15
8 Seger, Jon1998 Sewall Wright Award: William Donald HamiltonThe Sewall Wright Award was established in 1991 to honor active investigators who have contributed in especially significant ways to the conceptual unification of the biological sciences. This year's recipient is William D. Hamilton of Oxford University. Beginning in the 1960s with his papers on the...Evolution; Biological; Research1999
9 Miller, Joel Steven1H NMR investigation of the magnetic spin configuration in the molecule-based ferrimagnet [MnTFPP][TCNE]1H NMR line-shape measurements have been performed in the linear chain molecule-based ferrimagnet [MnTFPP][TCNE].xPhMe (TFPP=tetrakis(4-fluorophenyl)porphinato; TCNE=tetracyanoethylene) as a function of temperature. Hyperfine shifts of opposite sign were observed indicating the presence of two oppo...Magnetization; Magnets; Paramagnetic2002
10 Ailion, David Charles31P NMR spin-lattice relaxation: structural glass dynamics in Rb1-x(ND4)xD2PO4We performed 3 1P NMR measurements of the temperature-dependent spin-lattice relaxation time in several mixed single crystals of Rbi_x(ND4 ) xD2P04 [DRADP] having different ammonium concentration x (x =0.22, 0.44, 0.78) as well as in three pure single crystals (ND4)D2P04 [DADP], (NH4)H2P04 [ADP], an...NMR; Spin-lattice; Relaxation; Crystals; Glass; Spin-glass1993
11 Ailion, David Charles; Blinc, Robert35Cl spin-lattice relaxation in incommensurate bis(4-chlorophenyl)sulfoneThe 35C1 nuclear-quadrupole-resonance (NQR) spin-lattice relaxation rate in incommensurate bis(4- chlorophenyl)sulfone (BCPS) is determined by Raman processes below 60 K and by direct one-phonon processes above 60 K. The variation of the 35C1 spin-lattice relaxation rate over the incommensurate NQR...35Cl; Incommensurate bis(4-chlorophenyl)sulfone; Raman processes; NQR; Incommensurate systems1995-01
12 Morse, Michael DavidThe 3d?Ni(?F)3d10Cu???*? manifold of excited electronic states of NiCuDiatomic NiCu has been supersonically cooled in a molecular beam and investigated by resonant two-photon ionization spectroscopy. A total of nine band systems connecting the ground 3d?Ni3??Cu??, X 2?5/2 state to the 3d?Ni(3F)3d??Cu??*?? manifold of states have been found, and bands of eight of these...1992
13 Saam, Brian3He spin exchange cells for magnetic resonance imagingWe present a protocol for the consistent fabrication of glass cells to provide hyperpolarized (HP) 3He for pulmonary magnetic resonance imaging. The method for producing HP 3He is spin-exchange optical pumping. The valved cells must hold of order 1 atm.L of gas at up to 15 atm pressure. Because char...3He; Spin exchange cells; Hyperpolarized 3He; Pulmonary magnetic resonance imaging; Spin-exchange optical pumping; SEOP; Glass cells2002
14 Ailion, David Charles79Br nuclear-quadrupole-resonance lineshape and Raman-induced spin-lattice relaxation in the incommensurate phase of β- ThBr4We performed 7 9Br nuclear-quadrupole-resonance (NQR) line-shape and spin-lattice relaxation time measurements in the incommensurate (D system j8-ThBr4 over the temperature range 293-2.5 K. In addition, we extended the theory of the effects of Raman processes on amplitudon and phason spin-lattice re...Spin-lattice; NQR; Raman process; Line shape; Phason gap; Incommensurate systems1989
15 Morse, Michael DavidThe 846 nm A? ???u ? ??? band system of jet-cooled V?The 846 nm band system of jet-cooled 5?V2 has been recorded using resonant two-photon ionization spectroscopy, and is assigned as the A ? 3?u- +X ??g- band system. Both the ?'= 1u? ?" = 1g and ?'= Ou+ ??? = 0g+ subbands of the O-O band have been rotationally resolved and analyzed. Although the trans...1992
16 Ailion, David Charles93Nb NMR in the imcommensurate and quasi-commensurate phases of barium sodium niobateNMR spectra have been measured for the quadrupole perturbed 1/2 -1/2 transition of 9 3Nb in barium sodium niobate (BSN) between 300 and 650 K. The spectra are inhomogeneously broadened in the incommensurate (/) phase between T7 = 580 K and r c = 540 K as well as in the quasicommensurate (QC) phase ...NMR; Spectra; Barium sodium niobate; Line shapes1994
17 Morse, Michael DavidThe ?IIou ?X ???g band system of jet-cooled Ti?A band of jet-cooled ??Ti? has been located in the near infrared by resonant two-photon ionization spectroscopy. Rotational analysis has shown the band to be an ?? =O* ???=1 transition, which is consistent with the 3??g, ground state proposed by Bauschlicher ef al. [J. Chem. Phys. 95, 1057 ( 1991)]...1992
18 Miller, Joel Steven[Et4N]2[TCNE]2 (TCNE = tetracyanoethylene) - an example of an exceptionally long 2.827 Ã CC bondInterest in organic compounds exhibiting unusually long CC bonds has been the subject of several recent studies.1-3 The longest sp3-sp3 C-C single bond reported to date is 1.73 A°,1,2 whereas several [TCNE]22- (TCNE = tetracyanoethylene) dimers have been recently reported to form cation-assisted, l...Synthesis; Crystal; Solution2001
19 Sekercioglu, CaganA birders quide to TurkeyAs I write, it is early December and the woods outside my window lay dusted with snow like a holiday card by Currier and Ives. A minute ago, I looked up and caught a glimpse of an adult Cooper's Hawk dashing swiftly through the trees. It swooped up, landed on a branch, then briefly shook its tail an...2006-01-01
20 Morse, Michael DavidA pair potentials study of matrix-isolated atomic zinc. II. Intersystem crossing in rare-gas clusters and matricesThe mechanism of 4p 1P1?4p 3PJ intersystem crossing (ISC) following excitation of the 4p 1P1 level of matrix-isolated atomic zinc is investigated using a pair potentials approach. This is achieved by extending earlier ISC calculations on the Zn?RG2 and Zn?RG3 complexes to the square planar Zn?RG4 ...1998
21 Olivera, Baldomero M.; McIntosh, J. Michael; Hillyard, David R.A-superfamily of conotoxins: structural and functional divergenceThe generation of functional novelty in proteins encoded by a gene superfamily is seldom well documented. In this report, we define the A-conotoxin superfamily, which is widely expressed in venoms of the predatory cone snails (Conus), and show how gene products that diverge considerably in stru...Conotoxins; A-superfamily conotoxin2004-02-03
22 AAMC Award for Distinguished Research presentation for 1998This is a 3 minutes, 51 seconds video of the presentation of the American Association of Medical Colleges' Award for Distinguished Research to Mario Capecchi and Oliver Smithies for their independent work as pioneers in gene targeting.Transgenic mice; Gene targeting; Genetic engineering; Mutagenesis; Capecchi, Mario R.; Science - Awards - United States; Smithies, Oliver; Awards presentations1998
23 Voth, Gregory AlanAb initio calculations of reactive pathways for ?-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (?-HMX)Using the BLYP and B3LYP level of density functional theory, four possible decomposition reaction pathways of HMX in the gas phase were investigated: N?NO2 bond dissociation, HONO elimination, C?N bond scission of the ring, and the concerted ring fission. The energetics of each of these four mechan...Ab initio calculations; Reactive pathways; HMX2000
24 Wu, Yong-ShiAbsence of (1,0) supersymmetry anomaly in world-sheet gauge theories: a purely cohomological proofA purely cohomological proof is given for the absence of the (1,0) supersymmetry anomaly in gauge theories on a world sheet. In particular, it is shown that generalized cohomological approaches to anomalies in supersymmetric gauge theory, either formulated in whole superconnection space or only in t...World sheet; String theory; Superfields; Superspace1989-01
25 Capecchi, Mario R.Absence of radius and ulna in mice lacking hoxa-11 and hoxd-11.Mice with targeted disruptions in Hox genes have been generated to evaluate the role of the Hox complex in determining the mammalian body plan. This complex of 38 genes encodes transcription factors that specify regional information along the embryonic axes. Early in vertebrate evolution an ancestra...Alleles; Animals; Bone and Bones; Carpal Bones2003-09-02
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