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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 41 (2000), S. 4125-4153 
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: In this article we use one-dimensional nonlinear Schrödinger equations (NLS) to illustrate chaotic and turbulent behavior of nonlinear dispersive waves. It begins with a brief summary of properties of NLS with focusing and defocusing nonlinearities. In this summary we stress the role of the modulational instability in the formation of solitary waves and homoclinic orbits, and in the generation of temporal chaos and of spatiotemporal chaos for the nonlinear waves. Dispersive wave turbulence for a class of one-dimensional NLS equations is then described in detail—emphasizing distinctions between focusing and defocusing cases, the role of spatially localized, coherent structures, and their interaction with resonant waves in setting up the cycles of energy transfer in dispersive wave turbulence through direct and inverse cascades. In the article we underline that these simple NLS models provide precise and demanding tests for the closure theories of dispersive wave turbulence. In the conclusion we emphasize the importance of effective stochastic representations for the prediction of transport and other macroscopic behavior in such deterministic chaotic nonlinear wave systems. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 84 (1986), S. 2643-2648 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The separation of nitrogen isotopes by low temperature reaction of vibrationally excited nitrogen gas with oxygen has been studied, in which the formation of 15NO is theoretically favored. The potential yield and isotope separation coefficient β for this process were examined using a numerical simulation of the kinetic processes, which incorporated a steady-state isothermal model of the 14N2 and 14N15N vibrational distribution functions coupled with a non-steady-state kinetic model of the chemical system including N@B|2, O*2, N, O, and their reaction products. In the absence of O2, the vibrationally enhanced rate coefficient for the reaction N@B|2+O → NO+N was observed to be inversely proportional to the concentration of O atoms, due to VT loading of the N*2 distribution function. O2 was also found to greatly reduce the rate coefficient due to efficient depletion of the highly excited species via the reaction N2(v)+O2(0) → N2(v−1) +O2(1). Computed reaction yield increases dramatically if both the O@B|2 and N*2 vibrational temperatures are elevated, but only at the expense of greatly reduced β. The effective separative work for this process was estimated.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 6 (1959), S. 0 
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. Vorticella microstoma was grown non-axenically and axenically at pH 6.4. Vorticellas were maintained indefinitely on Bacillus cereus in a medium composed of Proteose-Peptone, Cerophyl, and the filtrate from boiled wheat kernels. Prolific growth occurred in 2-membered cultures. A medium containing hydrolyzed gelatin, aqueous liver extract, yeast nucleic acid hydrolysate, glucose, and penicillin is recommended for axenic growth.The potential value of vorticellids as research tools is discussed together with metabolic implications of supplementing sterile Proteose-Peptone broth with natural substances in particle form. The ineffectiveness of adding tryptophan, thiamine, glycine, and chelating agents to the axenic medium was considered. Refinements of the axenic medium are on trial.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 17 (1970), S. 0 
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. Cultures of Telotrochidium henneguyi, begun with logarithmic phase cells, were employed in an effort to produce synchronized fission by heat treatment. The cells tolerated a temperature range of 20–50 C; temperatures above 50 were lethal. When cells were exposed to a single shock for 30 min, 30–40 produced 0–50% encystment with total excystment after 10 min exposure to room temperature (heat shock range). No encystment occurred between 20–30 (intershock range). Encystment and excystment time varied directly with temperature between 40–50.The most effective procedure for inducing synchronized fission consisted of 6 cycle program of 38/28 C (shock temperature/intershock temperature) administered for 15/15 (shock/intershock duration in min). Division indices (DI = cells dividing/total population X 100 =%) ranged from 12–66% with a mean of 37.25%. In control cells, division indices ranged from 2–20% with an average of 12%. Inferences from these independently derived findings are discussed.
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 12 (1965), S. 0 
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SYNOPSIS. Telotrochidium henneguyi was cultured axenically. The major nutrients in medium T-3 were liver extract (1:20 National Biochemicals Co.), hydrolyzed yeast nucleic acid, glucose, and dl-β-hydroxybutyric acid; these were fortified with phosphate buffer, EDTA, and penicillin. The supplements were: 18 amino acids, 7 vitamins, 10 salts supplying trace-metals; uridylic, cytidylic, guanylic, and adenylic acids; thymidine-5-diphosphate, nicotinamide mononucleotide, and choline. Optimum conditions for axenic cultivation were obtained with phosphate buffer 2 × 10−1M, penicillin 5,000 U.S.P. units/ml, 23°C, pH 6.8. A monoxenic maintenance medium (“T-broth”) allowed prolific growth and produced trxmendous populations. It was composed of Bacillus cereus in an aqueous broth-concoction of Proteose-peptone, Cerophyl, and wheat kernels. Axenic T-3 medium supported serial subculture; yields of peritrichs were comparable to those in T-broth. Axenic yields were poorer in medium lacking the T-3 supplemenits but containing the major nutrients fortified with acid-hydrolyzed gelatin, serine, riboflavin, EDTA, CaCL, FeCI3, KCI, MgSO4·7 H2O, phosphate buffer, and penicillin. For rapid axenination, excystment was induced by vibrating encysted peritrichs ∼ 30 sec in a Vortex Jr. mixer. Freshly excysted animals were washed by centrifugation. A salt solution, not distilled water, was used for washing inoculants. Inocula consisting of 1 × 103 or more animals were obtained by conventional centrifuge methods.Extension of this investigation to construction of a chemically defined medium is discussed.
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  • 6
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 21 (1974), S. 0 
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: A synthetic medium for Opercularia coarctata was developed that contains 20 amino acids, 10 vitamins, an 8-component balanced salt solution, Fe2(SO4)3·(NH4)2SO4·24H2O, Tween 80, stigmasterol, a 7-component nucleic acid mixture, phenol red as an indicator, and 2,500 U.S.P. units/ml penicillin to maintain sterility. This medium supported axenic survival for 96 hr. Multiple supplements of thioctic acid, niacin, niacinamide, inositol, PABA, oleic acid, and Fe(NO3)2·9H2O instead of Fe2(SO4)3·(NH4)2SO4·24H2O coverted the survival medium into a growth medium, which permitted 36–45 days continuous cultivation of populations in excess of 4 × 103 cells/3.0 ml final volume. Five generations were produced during the 48 hr logarithmic growth period. Serial transfers at 72 hr and during periods of greatest cell density produced a maximum of 8 generations 96 hr after initiation but the medium failed to sustain growth through more than 6 serial transfers. Extension of this investigation to formulating a minimal axenic medium is discussed.
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  • 8
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    Unknown
    Saranac Lake, N.Y., etc. : Periodicals Archive Online (PAO)
    Management Review. 70:10 (1981:Oct.) 8 
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  • 9
    facet.materialart.
    Unknown
    Saranac Lake, N.Y., etc. : Periodicals Archive Online (PAO)
    Management Review. 67:1 (1978:Jan.) 8 
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Communications in mathematical physics 162 (1994), S. 175-214 
    ISSN: 1432-0916
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Notes: Abstract The theory of the focusing NLS equation under periodic boundary conditions, together with the Floquet spectral theory of its associated Zakharov-Shabat linear operator $$\hat L$$ , is developed in sufficient detail for later use in studies of perturbations of the NLS equation. “Counting lemmas” for the non-selfadjoint operator $$\hat L$$ , are established which control its spectrum and show that all of its eccentricities are finite in number and must reside within a finite discD in the complex eigenvalue plane. The radius of the discD is controlled by theH 1 norm of the potential $$\overrightarrow q $$ . For this integrable NLS Hamiltonian system, unstable tori are identified, and Backlund transformations are then used to construct global representations of their stable and unstable manifolds-“whiskered tori” for the NLS pde. The Floquet discriminant $$\Delta (\lambda ;\overrightarrow q )$$ is used to introduce a natural sequence of NLS constants of motion, [ $$[F_j (\overrightarrow q ) \equiv \Delta (\lambda = \lambda _j^c (\overrightarrow q );\overrightarrow q )$$ , where λ c j denotes thej th critical point of the Floquet discriminant Δ(λ)]. A Taylor series expansion of the constants $$F_j (\overrightarrow q )$$ , with explicit representations of the first and second variations, is then used to study neighborhoods of the whiskered tori. In particular, critical tori with hyperbolic structure are identified through the first and second variations of $$F_j (\overrightarrow q )$$ , which themselves are expressed in terms of quadratic products of eigenfunctions of $$\hat L$$ . The second variation permits identification, within the disc D, of important bifurcations in the spectral configurations of the operator $$\hat L$$ . The constant $$F_j (\overrightarrow q )$$ , as the height of the Floquet discriminant over the critical point λ c j , admits a natural interpretation as a Morse function for NLS isospectral level sets. This Morse interpretation is studied in some detail. It is valid globally for the infinite tail, $$\{ F_j (\overrightarrow q )\} _{|j| 〉 N} $$ , which is associated with critical points outside the discD. Within this disc, the interpretation is only valid locally, with the same obstruction to its global validity as to a global ordering of the spectrum. Nevertheless, this local Morse theory, together with the Backlund representations of the whiskered tori, produces extremely clear pictures of the stratification of NLS invariant sets near these whiskered tori-pictures which are useful in the study of perturbations of NLS. Finally, a natural connection is noted between the constants $$F_j (\overrightarrow q )$$ of the integrable theory and Melnikov functions for the theory of perturbations of the NLS equation. This connection generates a simple, but general, representations of the Melnikov functions.
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