66,638 research outputs found

    Current Classification of the Families of Coleoptera

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    (excerpt) Several works on the order Coleoptera have appeared in recent years, some of them creating new superfamilies, others modifying the constitution of these or creating new families, finally others are genera1 revisions of the order. The authors believe that the current classification of this order, incorporating these changes would prove useful. The following outline is based mainly on Crowson (1960, 1964, 1966, 1967, 1971, 1972, 1973) and Crowson and Viedma (1964). For characters used on classification see Viedma (1972) and for family synonyms Abdullah (1969). Major features of this conspectus are the rejection of the two sections of Adephaga (Geadephaga and Hydradephaga), based on Bell (1966) and the new sequence of Heteromera, based mainly on Crowson (1966), with adaptations

    Notes on Insect Injection, Anesthetization, and Bleeding.

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    (excerpt) In recent years there has been a burgeoning interest in insect cytogenetics, sometimes involving in vivo cultures of haematocytes for chromosomal analysis. Mitotic poisons, such as colchicine (Tyrkus, 1971), are commonly injected to produce metaphase plates. Likewise, injection of toxins is now common-place in applied insect research. However, surprisingly little general information on injection is available in the literature. The dictates of morphology determine the gross procedure to be used. The kind of needle and syringe, the amount of fluid to be administered, and the necessity of optical aids are a function of the size of the insect recipient. Once these decisions are made, other considerations must still be weighed, including comparative exoskeletal toughness and the insect\u27s stage of development, which are important in determining possible areas for needle penetration

    Phosphoproteins associated with cyclic nucleotide stimulation of ciliary motility in Paramecium

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    Permeabilized, MgATP-reactivated cells of Paramecium (models) respond to cyclic AMP and cyclic GMP by increasing forward swimming speed. In association with the motile response, cyclic AMP and 8-bromo-cyclic GMP (8-Br-cyclic GMP) stimulated protein phosphorylation. Cyclic AMP addition to permeabilized cells reproducibly stimulated the phosphorylation of 10 proteins, ranging in molecular weight from 15 to 110K (K = 10^3 M_r). 8-Br-cyclic GMP, which selectively activates the cyclic GMP-dependent protein kinase of Paramecium, stimulated the phosphorylation of a subset of the proteins phosphorylated by cyclic AMP. Ca^(2+) addition caused backward swimming and stimulated the phosphorylation of four substrates, including a 25K target that may also be phosphorylated in response to cyclic nucleotide addition. Ba^(2+) and Sr^(2+) also induced backward swimming, but did not cause detectable phosphorylation. To identify ciliary targets of cyclic nucleotide-dependent protein kinase activity, permeabilized cells were deciliated following reactivation of motility with Mg-[y-^(32)P]ATP in the presence or absence of cyclic nucleotide. Soluble proteins of the deciliation supernatant were enriched in 15 cyclic AMP-stimulated phosphoproteins, ranging in molecular weight from 15 to 95K. Most of the ciliary substrates were axonemal and could be released by high salt solution. A 29K protein that copurified in sucrose gradients with the 22S dynein, and a high molecular weight protein (greater than 300K) in the 19 S region were phosphorylated when cyclic AMP was added to permeabilized, motile cells. These data suggest that regulation of ciliary motility by cyclic AMP may include phosphorylation of dynein-associated proteins

    Compositions of near-Earth asteroids

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    The goal is to determine whether any of the near-earth asteroids contain water-bearing phyllosilicate (clay) minerals. If these minerals are present, they would provide a readily available source of water for propellant generation and use in life support systems. Telescopic detection of water on the near-earth asteroids is complicated because thermal emission from the asteroid itself masks the diagnostic absorption features for objects this close to the sun. Sophisticated thermal models are necessary to determine whether the absorption features are present. This year, development of these models was continued and more telescopic data to test the models was obtained

    INEQUALITY AND THE REFERENDUM LEVY

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    This study examines whether or not the referendum levy generates revenue disparities among school districts. More specifically, we hypothesize that if the referendum levy generates inequalities in school finance, a positive relationship will exist between: (1) district property wealth and use of the referendum; (2) district property wealth and the size of the referendum levy; and (3) district property wealth and revenue raised by the referendum levy. The discretionary levy is included throughout the analysis because, being equalized, it provides a relevant contrast to the referendum levy.Public Economics,

    Use of steel and tantalum apparatus for molten Cd-Mg-Zn alloys

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    Steel and tantalum apparatus contains various ternary alloys of cadmium, zinc, and magnesium used in pyrochemical processes for the recovery of uranium-base reactor fuels. These materials exhibit good corrosion resistance at the high temperatures necessary for fuel separation in liquid metal-molten salt solvents

    Localization transitions in non-Hermitian quantum mechanics

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    We study the localization transitions which arise in both one and two dimensions when quantum mechanical particles described by a random Schr\"odinger equation are subjected to a constant imaginary vector potential. A path-integral formulation relates the transition to flux lines depinned from columnar defects by a transverse magnetic field in superconductors. The theory predicts that the transverse Meissner effect is accompanied by stretched exponential relaxation of the field into the bulk and a diverging penetration depth at the transition.Comment: 4 pages (latex) with 3 figures (epsf) embedded in the text using the style file epsf.st
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