2,018 research outputs found

    Long-range forces between two excited mercury atoms and associative ionization

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    The long-range quadrupole-quadrupole (R5\sim R^{-5}) and leading dispersion (R6\sim R^{-6}) interactions between all pairs of excited Hg(6s6p6s6p) 3P0^3P_0, 3P1^3P_1, 3P2^3P_2, and 1P1^1P_1 atoms are determined. The quadrupole moments are calculated using the {\it ab initio} relativistic configuration-interaction method coupled with many-body perturbation theory. The van der Waals coefficients are approximated using previously calculated static polarizabilities and expressions for the dispersion energy that are validated with similar systems. The long-range interactions are critical for associative ionization in thermal and cold collisions, and are found to be quite different for different pairs of interacting states. Based on this knowledge and the short-range parts of previously calculated potential curves, improved estimates of the chemi-ionization cross sections are obtained.Comment: accepted in Phys Rev

    Individual Rights Under State Constitutions in 2018: What Rights are Deeply Rooted in a Modern-Day Consensus of the States?

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    This Article is actually the third and final article in a series that began with (A) Steven G. Calabresi & Sarah E. Agudo, Individual Rights Under State Constitutions When the Fourteenth Amendment Was Ratified in 1868: What Rights Are Deeply Rooted in American History and Tradition?; and (B) Steven G. Calabresi, Sarah E. Agudo, and Kathryn L. Dore, State Bills of Rights in 1787 and 1791: What Individual Rights Are Really Deeply Rooted in American History and Tradition?. This Article looks at what rights are protected by state constitutions today, in 2018, and compares our findings with the data we collected in our earlier two articles, which looked at rights under state constitutional law in 1868 when the Fourteenth Amendment was ratified, and at what rights were protected in state constitutional law in 1791 when the Federal Bill of Rights with its Ninth Amendment was ratified

    Using the local density approximation and the LYP, BLYP, and B3LYP functionals within Reference--State One--Particle Density--Matrix Theory

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    For closed-shell systems, the local density approximation (LDA) and the LYP, BLYP, and B3LYP functionals are shown to be compatible with reference-state one-particle density-matrix theory, where this recently introduced formalism is based on Brueckner-orbital theory and an energy functional that includes exact exchange and a non-universal correlation-energy functional. The method is demonstrated to reduce to a density functional theory when the exchange-correlation energy-functional has a simplified form, i.e., its integrand contains only the coordinates of two electron, say r1 and r2, and it has a Dirac delta function -- delta(r1 - r2) -- as a factor. Since Brueckner and Hartree--Fock orbitals are often very similar, any local exchange functional that works well with Hartree--Fock theory is a reasonable approximation with reference-state one-particle density-matrix theory. The LDA approximation is also a reasonable approximation. However, the Colle--Salvetti correlation-energy functional, and the LYP variant, are not ideal for the method, since these are universal functionals. Nevertheless, they appear to provide reasonable approximations. The B3LYP functional is derived using a linear combination of two functionals: One is the BLYP functional; the other uses exact exchange and a correlation-energy functional from the LDA.Comment: 26 Pages, 0 figures, RevTeX 4, Submitted to Mol. Phy

    Registration of Great Northern Common Bean Cultivar ‘Coyne’ with Enhanced Disease Resistance to Common Bacterial Blight and Bean Rust

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    Great northern common bean (Phaseolus vulgaris L.) ‘Coyne’ (Reg. No. CV-287, PI 655574) was developed by the dry bean breeding program at the University of Nebraska Agricultural Research Division and released in 2008. It was bred specifically for adaptation to Nebraska growing conditions and for enhanced resistance to common bacterial blight (CBB), a major disease of common bean caused by the seed-borne bacterium Xanthomonas campestris pv. phaseoli (Smith) Dye, and bean common rust Uromyces appendiculatus (Pers.:Pers) Unger. Coyne is a great northern F7:8 line derived from a three-way cross (G95023/Weihing//BelMiNeb-RMR-11). The first cross was made in winter 2003. The F7:8 was tested in advanced yield trials at Scottsbluff and Mitchell, NE, and in growers’ fields in Nebraska. Yield of Coyne was only 47 kg ha–1 lower than ‘Marquis’ in Morrill and Scotts Bluff, NE, counties. Reaction of Coyne to CBB under field conditions was consistent across 3 yr at the West Central Research and Extension Center, North Platte, NE, where fi eld disease ratings of 3.2, 3.5, and 4.4 were recorded in 2005, 2006, and 2007, respectively. Coyne has the Ur-3 and Ur-6 genes for resistance to common bean rust and carries the single dominant hypersensitive I gene that provides resistance to all non-necrotic strains of Bean common mosaic virus. Coyne has bright white seed, blooms 44 d after planting, and is a midseason bean, maturing 91 d after planting

    Registration of Common Bacterial Blight, Rust and Bean Common Mosaic Resistant Great Northern Common Bean Germplasm Line ABC-Weihing

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    Great northern common bean (Phaseolus vulgaris L.) germplasm line ABC-Weihing (Reg. No. GP-246, PI 647964) was developed by the University of Nebraska Agricultural Research Division in cooperation with USDA-ARS and released in 2006. This line, tested as NE1-05-4, was bred specifically for enhanced resistance to common bacterial blight (CBB), a major seed borne disease of common bean caused by the bacterium Xanthomonas campestris pv. phaseoli (Smith) Dye (Xcp). ABC-Weihing is a great northern BC5F3:6 line obtained from five backcrosses (‘Weihing’*5//‘Chase’/XAN 159). The first cross was made in spring 1997. Only BCnF1 plants resistant to Xcp isolates Dominican Republic DR-7 and Nebraska SC4A, as determined by multiple needle leaf inoculation tests in the greenhouse, were used for successive backcrossing. In addition to phenotypic selection for CBB resistance, marker-assisted selection for the resistant QTLlinked marker SU91 was conducted in the BC1F1, BC2F1, and ABC-Weihing. When inoculated with Nebraska Xcp strains in the field, ABC-Weihing exhibited resistance in both 2005 and 2006. ABC-Weihing has Ur-3 and Ur-6 genes for resistance to common bean rust and carries the single dominant hypersensitive I gene that provides resistance to all non-necrotic strains of the Bean common mosaic virus (BCMV). ABC-Weihing has bright white seed, blooms 45 d after planting, and is a midseason bean maturing 92 d after planting

    Structural Information in Two-Dimensional Patterns: Entropy Convergence and Excess Entropy

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    We develop information-theoretic measures of spatial structure and pattern in more than one dimension. As is well known, the entropy density of a two-dimensional configuration can be efficiently and accurately estimated via a converging sequence of conditional entropies. We show that the manner in which these conditional entropies converge to their asymptotic value serves as a measure of global correlation and structure for spatial systems in any dimension. We compare and contrast entropy-convergence with mutual-information and structure-factor techniques for quantifying and detecting spatial structure.Comment: 11 pages, 5 figures, http://www.santafe.edu/projects/CompMech/papers/2dnnn.htm

    Visión general de las percepciones regionales sobre el rol de la educación superior para el desarrollo humano y social

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    Nuestro informe ha estudiado en su Parte I temas globales seleccionados acerca del rol de la educación superior para el desarrollo humano y social. Este trabajo es una síntesis de las perspectivas regionales -África Subsahariana, Estados Árabes, Asia y el Pacífico, Europa, América del Norte y América Latina y el Caribe- acerca del rol de la educación superior para el desarrollo humano y social basado en la contribución de los autores en cinco áreas claves: una de ellas es el estado de la educacion superior en cada región desde la celebración de la Conferencia Mundial sobre Educación Superior (CMES, 1998); y otra de las cuatro áreas clave se refiere a los posibles roles futuros, estrategias y acciones de la educación superior para promover el desarrollo humano y social.Peer Reviewe

    Evo-devo of human adolescence: beyond disease models of early puberty

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    Despite substantial heritability in pubertal development, much variation remains to be explained, leaving room for the influence of environmental factors to adjust its phenotypic trajectory in the service of fitness goals. Utilizing evolutionary development biology (evo-devo), we examine adolescence as an evolutionary life-history stage in its developmental context. We show that the transition from the preceding stage of juvenility entails adaptive plasticity in response to energy resources, other environmental cues, social needs of adolescence and maturation toward youth and adulthood. Using the evolutionary theory of socialization, we show that familial psychosocial stress fosters a fast life history and reproductive strategy rather than early maturation being just a risk factor for aggression and delinquency. Here we explore implications of an evolutionary-developmental-endocrinological-anthropological framework for theory building, while illuminating new directions for research

    Decadal-scale hotspot methane ebullition within lakes following abrupt permafrost thaw

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    Thermokarst lakes accelerate deep permafrost thaw and the mobilization of previously frozen soil organic carbon. This leads to microbial decomposition and large releases of carbon dioxide (CO2) and methane (CH4) that enhance climate warming. However, the time scale of permafrost-carbon emissions following thaw is not well known but is important for understanding how abrupt permafrost thaw impacts climate feedback. We combined field measurements and radiocarbon dating of CH4 ebullition with (a) an assessment of lake area changes delineated from high-resolution (1–2.5 m) optical imagery and (b) geophysical measurements of thaw bulbs (taliks) to determine the spatiotemporal dynamics of hotspot-seep CH4 ebullition in interior Alaska thermokarst lakes. Hotspot seeps are characterized as point-sources of high ebullition that release 14C-depleted CH4 from deep (up to tens of meters) within lake thaw bulbs year-round. Thermokarst lakes, initiated by a variety of factors, doubled in number and increased 37.5% in area from 1949 to 2009 as climate warmed. Approximately 80% of contemporary CH4 hotspot seeps were associated with this recent thermokarst activity, occurring where 60 years of abrupt thaw took place as a result of new and expanded lake areas. Hotspot occurrence diminished with distance from thermokarst lake margins. We attribute older 14C ages of CH4 released from hotspot seeps in older, expanding thermokarst lakes (14CCH4 20 079 ± 1227 years BP, mean ± standard error (s.e.m.) years) to deeper taliks (thaw bulbs) compared to younger 14CCH4 in new lakes (14CCH4 8526 ± 741 years BP) with shallower taliks. We find that smaller, non-hotspot ebullition seeps have younger 14C ages (expanding lakes 7473 ± 1762 years; new lakes 4742 ± 803 years) and that their emissions span a larger historic range. These observations provide a first-order constraint on the magnitude and decadal-scale duration of CH4-hotspot seep emissions following formation of thermokarst lakes as climate warms
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