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  • 1
    Electronic Resource
    Electronic Resource
    Why does the white tip of stony coral grow so fast without zooxanthellae? (1989)
    Springer
    Marine biology 103 (1989), S. 359-363 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The photosynthesis of zooxanthellae in a coral polyp greatly enchances the calcification rate of a coral. However, the white tip of a coral branch is free of zooxanthellae yet still has a very high calcification rate. Furthermore, the reason for the difference is not clear. In this study, the amount of photopigment, total protein (TP), total organic carbon (TOC), ATP, and lipid in polyps from the white tip and brown stalk of a branch of stony coral were measured. Samples of Acropora hyacinthus and A. formosa were collected from southern Taiwan between 1985 and 1987. The results showed that the ATP concentration in polyps of the white tip was much higher than that in polyps of the brown stalk. Conversely, the amount of TP, TOC and measured lipids in polyps of the brown stalk were all higher than those of the white tip. It was the high concentration of ATP in cells that gave these polyp tips the vitality to sustain the energy requirements of such a rapid calification rate. Facilitated diffusion, due to the high metabolite gradient created by cell activity, could be the major driving force for the transport of photosynthetic product from stalk to tip.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00397270
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  • 2
    Electronic Resource
    Electronic Resource
    Coupling phases and amplitudes of minor constituents with temperature perturbations in the lower thermosphere (1994)
    Springer
    Annales geophysicae 12 (1994), S. 438-447 
    Details
    ISSN: 0992-7689
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Based on the linearized theory of atmospheric gravity waves (AGW) and considering the effects of temperature perturbation on the chemical rate coefficients, the formulae of coupling relations between nj/nj and T′/T driven by AGW (nj and T denote the background quantities) are described, the coupling phases and amplitudes of minor constituents O3, NO, H, OH, and O are analyzed in detail for the mesopause (86 km) and just upside of the O layer (100 km) at daytime. A general principle is outlined: the coupling phases are strongly dependent on density scale heights and perturbation scales, while the amplitudes are little affected by these two factors. A criterion to distinguish the coupling behavior is given: when the minor constituent number density scale height Hj satisfies 1-〈Gamma〉Hm/Hj〉0 (Hm denotes the scale height of the major constituent), the dynamical perturbation process always keeps the nj/nj in phase with T’/T, i.e. keeps the nj/nj in antiphase with that of the major constituent. The results obtained indicate that both the temperature dependence of reaction rate coefficients and the profile slopes of the O distribution may have a major influence on the behavior of the coupling relations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-994-0438-0
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  • 3
    Electronic Resource
    Electronic Resource
    Crystallographic analysis of Phe→Leu substitution in the hydrophobic core of barnase (1995)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 51 (1995), S. 220-231 
    Details
    ISSN: 1399-0047
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The crystal structure of a barnase mutant, Phe→Leu7 has been determined to 2.2 Å resolution. No structural rearrangement is observed near the mutated residue. The F7L mutation is highly destabilizing and this is caused by the loss of extensive van der Waals contacts that wild-type Phe7 made with its neighbouring residues, and the exposure of a large hydrophobic pocket on the surface of the protein. The side-chain conformations of the mutated Leu7 residue have torsion angles χ1 ranging from −138° to −168° and χ2 ranging from +16° to +70°, for the three molecules in the asymmetric unit. These angles do not agree with the most frequently observed conformations in the protein side-chain rotamer library [Ponder & Richards (1987). J. Mol. Biol. 193, 775–791] . However, when compared to a more recent `backbone-dependent' rotamer library [Dunbrack & Karplus (1993). J. Mol. Biol. 230, 543–574], the side-chain conformation of Leu7 agrees well with that of the most frequently observed rotamers. The side-chain conformation of Leu7 was found to be dictated by two factors: it has the lowest conformational energy and it buries the most hydrophobic surface area.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0907444994008851
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  • 4
    Electronic Resource
    Electronic Resource
    T Cell-Derived Lymphokines That Induce IgM and IgG Secretion in Activated Murine B Cells (1984)
    Oxford, UK : Blackwell Publishing Ltd
    Immunological reviews 78 (1984), S. 0 
    Details
    ISSN: 1600-065X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-065X.1984.tb00480.x
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  • 5
    Electronic Resource
    Electronic Resource
    Transfer-matrix analysis of waveguide phase modulator using the linear electro-optic effect of asymmetric quantum wells (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 4903-4905 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The phase modulation of asymmetric quantum-well embedded waveguides is studied. In order to accurately analyze the modulation from quantum wells and optimize the performance of waveguide modulators, a transfer-matrix method is developed to calculate the bias-controlled phase modulation of waveguides with an arbitrary refractive index distribution. The refractive index change may include those from free-carrier effects and the nonlinear effects of bulk material and quantum wells. The linear electro-optic effect introduced by asymmetric quantum wells can potentially be used to improve the frequency performance of semiconductor waveguide phase modulators.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357271
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  • 6
    Electronic Resource
    Electronic Resource
    X-ray and particle diagnostics of a high-density plasma by laser implosion (invited) : Eighth topical conference on high−temperature plasma diagnostics (1990)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 61 (1990), S. 3235-3240 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A series of laser fusion implosion experiments of plastic hollow shell targets was performed by using the Gekko XII glass laser in order to achieve the required fuel areal density for ignition. Introducing random phase plates to improve illumination uniformity, high-density compression of more than 600 times deuterium liquid density has been achieved. The implosion dynamics and symmetry were observed with a spatially resolved x-ray streak camera and an x-ray multiframing camera. The three-dimensional emission profile of the laser-heated plasma was reconstructed from the x-ray images by use of computed tomography and was compared with the laser illumination profiles. The areal density of the imploded core was measured by the neutron activation of a silicon tracer, the secondary reaction method, and the knock-on proton method. Although the measured density and areal density were consistent with those from 1-D hydrodynamic simulation, experimental neutron yields were significantly lower than those predicted by the simulation for convergence ratios larger than 20. This suggests that better implosion uniformity is required to create a hot spark.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1141654
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  • 7
    Electronic Resource
    Electronic Resource
    Blind reconstruction of x-ray penumbral images (1998)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 1966-1969 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: We proposed a method to estimate the point-spread function from the power cepstrum of the penumbral image in this paper. It is used as a preprocessing step before deconvolution. Both computer simulations and experimental results for real x-ray imaging demonstrated the potential of the method for practical applications. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1148881
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  • 8
    Electronic Resource
    Electronic Resource
    Neutron penumbral imaging at Gekko XII (abstract) : Eighth topical conference on high-temperature plasma diagnostics (1990)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 61 (1990), S. 3230-3230 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: 14 MeV DT neutrons emitted from a laser-imploded target have been imaged by using a penumbral aperture camera. This system consists of a 6-cm-thick tungsten toroidal aperture, an array of plastic scintillators, an optical fiber coupled two-stage image intensifier, and a cooled CCD camera. A burn region has been observed with a spatial resolution of ∼35 μm at a neutron yield of 5×1011. The spatial resolution was determined by a pixel resolution, the accuracy of the aperture fabrication, the alignment accuracy of the aperture, the signal-to-noise ratio of an encoded image, and the statistical fluctuation in detecting neutrons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1141645
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  • 9
    Electronic Resource
    Electronic Resource
    Development of x-ray emission computed tomography for ICF research : Eighth topical conference on high−temperature plasma diagnostics (1990)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 61 (1990), S. 2783-2785 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A computed tomographic (CT) technique has been developed to diagnose laser-irradiated spherical targets using x-ray emissions. The three-dimensional (3-D) x-ray distribution was reconstructed by using an algebraic reconstruction technique (ART) from x-ray pinhole camera images obtained along different sight directions. 3-D distributions of electron temperature and density were measured by use of an absorption filter technique. Time-resolved 3-D x-ray emission images from an imploding hollow shell target were reconstructed with less than 100 ps temporal resolution by using x-ray multiframing cameras.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1141830
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  • 10
    Electronic Resource
    Electronic Resource
    Observation of a large capacitive current in a double barrier resonant tunneling diode at resonance (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 64 (1994), S. 2276-2278 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Capacitance-voltage measurements of double barrier In0.53Ga0.47As/AlAs resonant tunneling diodes show a large capacitance peak at a bias near resonance. The measured peak capacitance is about five times larger than the calculated depletion capacitance. This large capacitance is interpreted as the capacitance between the emitter and the quantum well, which is activated near resonance only when the quantum well has a sufficient number of electrons to screen the ac electric field. An equivalent circuit with the new added series RC component is proposed and the effect on the high frequency operation of a resonant tunneling diode is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.111642
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