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CreatorTitleDescriptionSubjectDate
301 Clayton, Dale H.Neotropical tineidae, II: biological notes and descriptions of two new moths phoretic on spiny pocket mice in Costa Rica (Lepidoptera: Tineoidea)Two new species of tineid moths discovered riding on the backs of two species of spiny pocket mice (Heteromyidae) in Costa Rica are described. Amydria selvae, new species, was found on Heteromys desmarestianus Gray in the rainforest at Finca La Selva and Ptilopsaltis santarosae, new species, occurr...Neotropical Tineidae; Phoretic moths; Amydria selvae; Heteromys desmarestianus; Ptilopsaltis santarosae; Liomys salvini; Mouse moths1986
302 Armentrout, Peter B.Effect of kinetic and electronic energy on the reactions of Mn+ with H2, HD and D2Reactions of several electronic states of Mn+ with H2, HD, and D2 have been examined using guided ion beam mass spectroscopy. The excitation function for the ground state of Mn+ ( 75) has two regions: one of very low reactivity at threshold and another more efficient pathway at higher energies. In ...Ion-molecule reactions; Translational energy; Bond energy; Threshold behavior; Endothermic reactions; Metal ions; Manganese; Hydrogen1986
303 Beckerle, Mary C.Identification of a new protein localized at sites of cell-substrate adhesionA new protein found at sites of cellsubstrate adhesion has been identified by analysis of a nonimmune rabbit serum. By indirect immunofluorescence this serum stains focal contacts (adhesion plaques) and the associated termini of actin filament bundles in cultured chicken cells.Actin; Nonimmune rabbit serum; Polypeptide1986
304 Seger, JonIdeas in ecologyThe word "ecology" means different things to different people. For example, during the last 25 years or so the word has been used to label attitudes, life-styles, consumer goods, political parties, and college courses. In the 1960s one university renamed its "Home Economics" course "Home Ecology."...Behavioral ecology; Population ecology1986
305 Ailion, David CharlesNuclear magnetic resonance in random fields: cluster formation and local dynamics of a deuteron glassNMR data show that the deuteron "pseudo spin-glass" transition in Rbi- X(ND4)*D2P04 is not just a simple kinetic slowing down process but is characterized by a gradual condensation of randomly polarized clusters as expected if we deal with a percolation transition in eigenstate space. The results pr...NMR; Nuclear magnetic resonance; Random fields; Spin lattice1986
306 Blair, David F.Chemical and spectroscopic evidence for the formation of a ferryl Fea3 intermediate during turnover of cytochrome c oxidaseWhen partially reduced cytochrome c oxidase samples are reoxidized with dioxygen, an EPR-silent dioxygen intermediate, which is at the three-electron level of dioxygen reduction, is trapped at the dioxygen reduction site. The intermediate has novel spectral features at 580 and 537 nm. Combined op...Cytochrome c oxidase; EPR; Fea3 intermediate; Reduction1986
307 Vardeny, Zeev ValentinePicosecond dynamics of photoexcitations in amorphous multilayer structuresWe report on measurements of ultrafast relaxation processes in transmission and reflection in amorphous multilayer structures consisting of a-Si:H, a-SiNx:H, a-SiOx:H, and a-Ge:H. The decays recorded in transmission in the a-Si:H/a-SiNx :H and a-Si:H/a-SiOx :H multilayers depend strongly on the sili...Photoexcitations1986
308 Jorgensen, ErikMultiple transcripts from the Antennapedia gene of Drosophila melanogasterThe structures of four major transcripts from the homeotic gene Antennapedia of Drosophila melanogaster were determined. These transcripts constitute two RNA classes, each class initiating from a unique promoter but sharing 3' exons. Within the shared sequences is a major open reading frame encoding...Mutations; Sequences ; RNA1986
309 Armentrout, Peter B.C+(2P)+H2(D2,HD)→CH+(CD+)+H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2, and HD) to form methyliumylidene (CH+ and CD+) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants from th...Methyliumylidene; Endothermic reactions; Isotope effect; Threshold energy1986
310 Mattis, Daniel C.Few-body problem on a latticeThe author explores some of the inherent simplifications of "quantum lattice physics." He distinguishes between fermions and bosons and analyzes the n-body problem for each, with n = 1,2,3... typically a small number. With delta-function (zero-range) interactions, the three-body problem on a lattice...Quantum; Electrons; Spin1986
311 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. I. Recognition of a specific axonal pathway by the pCC neuronThe selective affinities that growth cones display for specific axonal surfaces give rise to stereotyped patterns of selective fasciculation. Previous studies on cell recognition by neuronal growth cones in the grasshopper embryo led to the proposal and initial experimental testing of the labeled-p...Fascicle; Axon; Affinity1986
312 Symko, Orest GeorgeDiscrete spatial filtering with SQUID gradiometers in biomagnetismFirst-, second-, and third-order gradiometers used in detecting biomagnetic signals are analyzed as spatial niters. Their transfer functions independent of the source to be measured are presented and both the magnitude and phase characteristics of the transfer functions are analyzed. The distortion ...Spatial filtering; SQUID gradiometers; Fourier transform1986
313 Armentrout, Peter B.Transition metal cluster ion chemistryThe reactivity and thermochemistry of ionic metal atoms and clusters has been explored using guided ion beam mass spectrometry. With this apparatus, cross sections of ion-molecule reactions can be measured from thermal energies to hundreds of eV. Application to metal cluster chemistry demonstrates...Metal clusters; Manganese ions; Endothermic reactions1986
314 Williams, Clayton C.Optical ranging by wavelength multiplexed interferometryA new optical technique is described for measurement of absolute distance. The approach is based upon a wavelength multiplexed heterodyne interferometer with FM demodulation. By temporally multiplexing discrete wavelengths in a heterodyne interferometer, a complete elimination of interferometric ra...Optical ranging; Distance1986
315 Miller, Joel Steven; Epstein, Arthur J.Linear chain ferromagnetic charge transfer compoundsCharge transfer complexes possessing a ... DADA ... structure with both the donor, D, and acceptor, A, being S = 1/2 radicals may exhibit cooperative magnetic phenomena. The complex [Fe(C5Me5)2]+ [TCNQ]-. exhibits metamagnetic behavior. The similarly structured [TCNE]-. and [C4(CN)6]-. complexes ar...Spin; Exchange; Molecular1986
316 Williams, Clayton C.High resolution thermal microscopyA new high resolution thermal microscope has been demonstrated capable of imaging thermal fields with sub 1000 angstom resolution. It is based upon a non-contacting near field thermal probe. The thermal probe consists of a thermocouple sensor on the end of a tip with sub 1000 angstrom dimensions. Th...1986
317 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. II. Recognition of a specific axonal pathway by the aCC neuronIn the previous paper, we experimentally analyzed the selective affinity of the pCC growth cone for the MP1/dMP2 fascicle in the grasshopper embryo. Here we describe a similar experimental analysis demonstrating the selective affinity of the aCC growth cone for the U fascicle. These results support...Axon; Cell; Fascicle1986
318 Capecchi, Mario R.; Thomas, Kirk R.High frequency targeting of genes to specific sites in the mammalian genomeWe corrected a defective gene residing in the chromosome of a mammalian cell by injecting into the nucleus copies of the same gene carrying a different mutation. We determined how the number, the arrangement, and the chromosomal position of the integrated gene, as well as the number of injected mo...Homologous recombination; Mutant genes; Mammalian genome1986
319 Armentrout, Peter B.C+(2P) + H2(D2,HD)→CH+(CD+) + H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15 eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2 , and HD) to form methyliumylidene (CH+ and C D + ) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants fro...Ion-molecule reactions; Isotope effects; Translational energy; Threshold behavior; Endothermic reactions1986
320 Armentrout, Peter B.Spin-orbit state-selected reactions of Kr+(2P3/2 and 2P1/2) with H2, D2, and HD from thermal energies to 20 eV c.m.Spin-orbit state-selected reactions of K r + (2Pj), J = 3/2 and / = 1/2, with isotopic molecular hydrogen (H2 , D2 , and HD) to form KrH+ and Kr D+ are investigated using guided ion beam techniques. Reaction cross sections for each spin-orbit state are measured as a function of the relative trans...Spin-orbit; Krypton ions; Hydrogen isotopes; Isotope effects; Potential energy surfaces; Ion-molecule reactions1986
321 Vardeny, Zeev ValentineObservation of molecular vibrations in real timeIn a recent Letter Rosker, Wise, and Tang1 have reported ultrafast optical measurements on two large dye molecules, malachite green and nile blue 690. Using the transmission-correlation technique with 40-fs light pulses, they measured photoinduced changes in optical transmission and found a resp...Molecular vibrations; Nile blue 690; Dyes1986
322 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. III. Recognition of specific glial pathwaysIn the previous 2 papers, we focused on the selective affinities that growth cones display for specific axonal pathways. Little is known, however, about how this orthogonal scaffold of axonal pathways in the CNS is established in the first place, and what, if any, role glia might play in these even...CNS; Nerve; Cells1986
323 Olivera, Baldomero M.Calcium channel antagonists: ω-conotoxin defines a new high affinity siteThe ω-conotoxins, a class of Ca2+ channel antagonists from fish-hunting marine snails, have recently been described (Olivera, B. M., McIntosh, J. M., Zeikus, R., Gray, W. R., Varga, J., Rivier, J., de Santos, V., and Cruz, L. J. (1985) Science, 230, 1338-1343). One of these peptide neurotoxins...Conotoxins; Calcium channels; Synaptosomes; Neurotoxins1986
324 Miller, Joel Steven; Epstein, Arthur J.Ferromagnetic properties of one-dimensional decamethylferrocenium tetracyanoethylenide (1:1): [Fe(n5-C5Me5)2].+[TCNE].-[Fe(C5Me5)2].+ [TCNE].-- has been characterized by magnetic susceptibility to possess dominant ferromagnetic interactions; its structure has been determined by X-ray crystallography.Susceptibility; Crystal; Magnetic1986
325 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. IV. Temporal delay experimentsIn the previous 3 papers, we demonstrated that neuronal growth cones display selective affinities for both specific axonal and glial pathways in the grasshopper embryo; for example, the pCC growth cone selectively recognizes the MPl/dMP2 axons, while the aCC growth cone selectively recognizes the U...Pathways; Neurons; Axons1986
301 - 325 of 1,952