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Creator | Title | Description | Subject | Date |
| 76 |
 |
Mattis, Daniel C. | Mobility gap and anomalous dispersion | It is shown that anomalous dispersion of quasiparticles leads to nonpropagating states. Therefore regions of anomalous dispersion define a sort of "mobility gap." Using the coherent-potential approximation, we calculate the conditions for obtaining such a mobility gap in a disordered binary alloy. J... | Mobility gap; Disordered media; Quasiparticles | 1973-09 |
| 77 |
 |
Capecchi, Mario R. | Altered enzymes in drug-resistant variants of mammalian tissue culture cells. | Two selective procedures are compared in an effort to isolate variants of mouse L cells containing structural gene mutations. Among the resulting variant cloned cell lines are found two types of alterations in theenzyme hypoxanthine phosphoribosyl transferase (EC 2.4.2.8.) (1): enzyme with altered ... | Drug Resistance; Azaguanine; Clone Cells; Hypoxanthines | 1973-11 |
| 78 |
 |
Symko, Orest George | Background signals in SQUID magnetometers | Since a SQUID magnetometer is an extremely sensitive device capable of detecting minute magnetic flux changes in a sample, it will also detect unwanted signals from materials near the magnetometer. The presence of temperature dependent "background signals" limits the accuracy of measurements of ... | SQUID magnetometer; Background signals | 1974 |
| 79 |
 |
Mattis, Daniel C. | New wave-operator identity applied to the study of persistent currents in 1D | We show that a large class of backward-scattering matrix elements involving Δk ~ + 2k F vanish for fermions interacting with two-body attractive forces in one dimension. (These same matrix elements are finite for noninteracting particles and infinite for particles interacting with two-body repulsiv... | Persistent current; Supercurrents | 1974 |
| 80 |
 |
Mattis, Daniel C. | Conductivity of one-dimensional interacting fermions* | Using an exactly soluble model, the decay rate of a current-carrying state of one-dimensional fermions is calculated in the presence of random scatterers at finite temperature and the dc conductivity thereby inferred. For interacting fermions it is modified by a factor (T/T + θ)g, where g is a posi... | Fermi gas | 1974-04 |
| 81 |
 |
Mattis, Daniel C. | Effect of band structure on ferromagnetism* | We extend Nagaoka's study of the ferromagnetism of nearly half-filled bands in the infinite-repulsion limit of the Hubbard model by including next-nearest-neighbor tight-binding overlap matrix elements K2. Particles can now get past one another, even in one dimension. We find corroboration of Nagaok... | Eigenstates; Spin waves | 1974-08 |
| 82 |
 |
Mattis, Daniel C. | Dynamic properties of a nonsuperfluid Bose liquid in the random-phase approximation | The dynamic structure factor S(k,w) of a nonideal Bose liquid is calculated within the random-phase approximation and compared with neutron scattering data by Cowley and Woods for liquid helium in the temperature range Tλ<T≤4.2°K, with the conclusion that the model is wholly inadequate. A low-f... | Bose liquid; Random-phase approximation; Overdamping | 1974-11 |
| 83 |
 |
Capecchi, Mario R. | Selective degradation of abnormal proteins in mammalian tissue culture cells. | The degradation rates of several missense mutants of hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8) in mouse L cells are compared to those of the wild-type enzyme. Although the rates of total protein breakdown in the mutant cell lines are identical to that of the parental L cell line, ... | Gene Expression Regulation; Mice, Transgenic; Microscopy, Fluorescence | 1974-12-01 |
| 84 |
 |
Davidson, Diane W. | Preliminary study of seed predation in desert and montane habitats | Multifactorial experiments in which domestic seeds in shallow glass containers were distributed in desert and montane habitats provided data on identity of seed predators (whether rodents or ants), spatial and temporal pattern of their foraging activities, and their preferences for sizes and species... | Ant; Competition; Granivory; Predators, Seed; Rodent; Seed selection | 1975 |
| 85 |
 |
Gesteland, Raymond F.; Atkins, John F. | Origin and destiny of adenovirus proteins | Lytic infection of human cells by adenovirus proceeds by a temporal expression of genes. Classically two phases have been defined: an early phase, which includes events occurring before the onset of DNA synthesis (8 hours), and a late phase, including events whose existence depends on the onset of... | Protein Biosynthesis; DNA, Viral; Adenoviridae; RNA, Viral; Time Factors | 1975 |
| 86 |
 |
Capecchi, Mario R. | Purification and characterization of mouse hypoxanthine-guanine phosphoribosyltransferase. | Hypoxanthine-guanine phosphoribosyltransferase (HGPR transferase) (EC 2.4.2.8) has been purified approximately 4500-fold to apparent homogeneity from mouse liver. The procedure involves the use of affinity chromatography and was designed to be readily adaptable to small scale isolations. The enzyme ... | Buffers; Centrifugation, Density Gradient; Chromatography, Affinity; Chromatography, Gel; Chromatography, Ion Exchange; Electrophoresis, Polyacrylamide Gel | 1975-01-31 |
| 87 |
 |
DeTar, Carleton | Reggeon calculus as a low-order perturbation theory for the Pomeron | We review the foundations of the Gribov Reggeon calculus with an emphasis on the relationship between the energy-plane and J-plane descriptions of the diagrams of the calculus. The question of the "large-rapidity-gap cutoff' for the Pomeron and the problem of signature are treated in more detail t... | Singularities; Reggeon calculus; Reggeon field theory; Two-body propagator | 1975-02 |
| 88 |
 |
Sokolsky, Pierre | Search for backward A1 and A2 production in π-p→pπ- π + π- at 8 GeV/c* | Backward meson production in there action π- p→ Pπ +π- has been studied with use of a streamer chamber triggered by the detection of a fast forward proton. For cos0* <-0.98 we find no evidence of At or A2 production, and we determine total backward cross - section upper limits (95% confidence) ... | | 1975-03 |
| 89 |
 |
Vardeny, Zeev Valentine | Lattice dynamics of CuCl | A satisfactory fit for CuCl phonon dispersion relations is obtained for the first time. This fit is achieved by modifying the branch assignment of a few 2 phonons and by applying a double-shell model to fit the observed phonon data. | CuCl; Phonon dispersion relations | 1975-06 |
| 90 |
 |
Capecchi, Mario R. | Yeast super-suppressors are altered tRNAs capable of translating a nonsense codon in vitro. | tRNA isolated from two different yeast super-suppressor strains translates a known nonsense mutation in vitro, whereas tRNA from a closely related nonsuppressing strain does not. Suppression was assayed by translation of RNA isolated from an amber coat mutant of bacteriophage Qbeta (GB11) in a prote... | Codon; Escherichia coli; Protein Biosynthesis | 1975-11 |
| 91 |
 |
Symko, Orest George | Application of SQUID magnetometer to nuclear magnetic thermometry | This paper presents an application of a SQUID magnetometer for low temperature thermometry using the magnetic properties of a nuclear paramagnet. The static magnetization of a material which obeys Curie's law provides a very sensitive means of thermometry. Also included in the device is the capabi... | SQUID magnetometer; Nuclear magnetic thermometry; Low temperature thermometry | 1976 |
| 92 |
 |
Olivera, Baldomero M. | Preliminary study of Conus venom protein | ALTHOUGH THE TOXICITY of venoms of the genus Conus has been known since a report by RUMPHIUS in 1705 (VAN BENTHEM-JUTTINO, 1959), these venoms have been studied only intermittently since. Biochemical studies have not been carried out to any great extent; the last major study on the biochemistry of... | Conotoxins; Conus venom | 1976 |
| 93 |
 |
Christiansen, Richard Wesley | Word recognition in continuous speech using linear prediction analysis | A promising method of automatic word recognition in continuous speech, recently designated as word spotting, has been demonstrated. The method uses error residual ratios from LPC (Linear Predictive Coding) vocoder analysis for waveform comparison and a dynamic programming procedure for time regist... | Word recognition; continuous speech; linear prediction analysis; word spotting; error residual ratios; LPC; Linear Predictive Coding; vocoder analysis | 1976 |
| 94 |
 |
Sokolsky, Pierre | Backward 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 |
| 95 |
 |
Mattis, Daniel C. | Reconstructing the thermodynamic properties out of scattering cross sections | Using Green's functions of electrons scattered at an impurity site, I derive expressions for the energy όU solely in terms of the electronic scattering cross section,, My formulas can correlate the excess specific heat of dilute alloys with their resistivity. Formulas are derived for nontrivial sca... | Wolff's function | 1976-01 |
| 96 |
 |
Mattis, Daniel C. | Operator identity and applications to models of interacting electrons | By correct reduction of some quartic forms in fermion field operators, I eliminate all but a constant and some quadratic terms. I can use this to transform the Wolff model, of a magnetic impurity in a nonmagnetic metal, into a solvable quadratic form in fermions. Applying the same method (with less ... | Fermi operators | 1976-03 |
| 97 |
 |
Sokolsky, Pierre | Observation of the reaction νµ + p →νµ + p+ | We have observed the elastic neutral - current reaction vµ +p→vµ +p and compared it to the quasielastic reaction vµ +n→µ +p. We have measured the ratio of the two reactions to be 0.23 ± 0.09. | | 1976-07 |
| 98 |
 |
Keller, Robert M. | Denotational models for parallel programs with indeterminate operators | Several approaches to networks of concurrently-operating modules involving indeterminacy are discussed. Techniques for representing the denotational semantics of such networks, and for verifying properties of them, are presented, including an oracle approach, an axiomatic approach, a data-type reduc... | Denotational models; Indeterminate operators | 1977 |
| 99 |
 |
Boll, Steven F. | Improving linear prediction analysis of noisy speech by predictive noise cancellation | The analysis of speech using Linear Prediction is reformulated to account for the presence of acoustically added noise and a technique is presented for reducing its effect on parameter estimation. The method, called Predictive Noise Cancellation (PNC), modifies the noisy speech autocorrelations ... | Linear prediction; Predictive Noise Cancellation; Noisy speech; Sppech analysis | 1977 |
| 100 |
 |
Ailion, David Charles | Nuclear double resonance: cross relaxation rates between two spin species | A rotating-frame nuclear-double-resonance experiment is reported in which the cross-relaxation rates between 7Li and 6Li in powdered lithium metal were measured. The theory developed my McArthur, Hahn, and Walstedt (MHW) is applied to these data and good agreement is obtained. We also apply this t... | Nuclear-double-resonance; Lithium; MHW; Cross-relaxation | 1977 |
