Time-dependent density functional study of the electronic potential energy curves and excitation spectrum of the oxygen molecule

Orbital energies, ionization potentials, molecular constants, potential energy curves, and the excitation spectrum of O(2) are calculated using time-dependent density functional theory (TDDFT) with Tamm-Dancoff approximation (TDA). The calculated negative highest occupied molecular orbital energy (-epsilon(HOMO)) is compared with the energy difference ionization potential for five exchange correlation functionals consisting of the local density approximation (LDAxc), gradient corrected Becke exchange plus Perdew correlation (B(88X)+P(86C)), gradient regulated asymptotic correction (GRAC), statistical average of orbital potentials (SAOP), and van Leeuwen and Baerends asymptotically correct potential (LB94). The potential energy curves calculated using TDDFT with the TDA at internuclear distances from 1.0 to 1.8 A are divided into three groups according to the electron configurations. The 1pi(u) (4)1pi(g) (2) electron configuration gives rise to the X (3)Sigma(g) (-), a (1)Delta(g), and b (1)Sigma(g) (+) states; the 1pi(u) (3)1pi(g) (3) electron configuration gives rise to the c (1)Sigma(u) (-), C (3)Delta(u), and A (3)Sigma(u) (+) states; and the B (3)Sigma(u) (-), A (1)Delta(u), and f (1)Sigma(u) (+) states are determined by the mixing of two or more electron configurations. The excitation spectrum of the oxygen molecule, calculated with the aforementioned exchange correlation functionals, shows that the results are quite sensitive to the choice of functional. The LDAxc and the B(88X)+P(86C) functionals produce similar spectroscopic patterns with a single strongly absorbing band positioned at 19.82 and 19.72 eV, respectively, while the asymptotically corrected exchange correlation functionals of the SAOP and the LB94 varieties yield similar excitation spectra where the computed strongly absorbing band is located at 16.09 and 16.42 eV, respectively. However, all of the exchange correlation functionals yield only one strongly absorbing band (oscillator strength greater than 0.1) in the energy interval of 0-20 eV, which is assigned to a X (3)Sigma(g) (-) to (3)Sigma(u) (-) transition. Furthermore, the oxygen molecule has a rich spectrum in the energy range of 14-20 eV and no spin allowed absorption bands are predicted to be observed in the range of 0-6 eV

Resilience of a eucalypt forest woody understorey to long-term (34–55 years) repeated burning in subtropical Australia

We investigated the effects of annual burning since 1952, triennial burning since 1973, fire exclusion since 1946 and infrequent wildfire (one fire in 61 years) on woody understorey vegetation in a dry sclerophyll eucalypt forest, south-eastern Queensland, Australia. We determined the influence of these treatments, and other site variables (rainfall, understorey density, topsoil C : N ratio, tree basal area, distance to watercourse and burn coverage) on plant taxa density, richness and composition. The richness of woody understorey taxa 0–1 m in height was not affected by burning treatments, but richness of woody plants 1–7.5 m in height was lower in the annually burnt treatment than in the triennially burnt treatment from 1989 to 2007. Fire frequency and other site variables explained 34% of the variation in taxa composition (three taxon groups and 10 species), of which 33% of the explained variance was explained by fire treatment and 46% was explained by other site variables. Annual burning between 1974 and 1993 was associated with lower understorey densities mainly due to reduced densities of eucalypts 1–7.5 m in height. Triennial burning during the same period was associated with higher densities of eucalypts 0–7.5 m in height relative to the annually burnt and unburnt treatments. Most woody taxa persisted in the frequently burnt treatments through resprouting mechanisms (e.g. lignotuberous regeneration), and fire patchiness associated with low-intensity burning was also found to be important. Persistence of plants <1 m tall demonstrates the resilience of woody taxa to repeated burning in this ecosystem, although they mainly exist in a suppressed growth state under annual burning

The impact of facial abnormalities and their spatial position on perception of cuteness and attractiveness of infant faces

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Research has demonstrated that how “cute” an infant is perceived to be has consequences for caregiving. Infants with facial abnormalities receive lower ratings of cuteness, but relatively little is known about how different abnormalities and their location affect these aesthetic judgements. The objective of the current study was to compare the impact of different abnormalities on the perception of infant faces, while controlling for infant identity. In two experiments, adult participants gave ratings of cuteness and attractiveness in response to face images that had been edited to introduce common facial abnormalities. Stimulus faces displayed either a haemangioma (a small, benign birth mark), strabismus (an abnormal alignment of the eyes) or a cleft lip (an abnormal opening in the upper lip). In Experiment 1, haemangioma had less of a detrimental effect on ratings than the more severe abnormalities. In Experiment 2, we manipulated the position of a haemangioma on the face. We found small but robust effects of this position, with abnormalities in the top and on the left of the face receiving lower cuteness ratings. This is consistent with previous research showing that people attend more to the top of the face (particularly the eyes) and to the left hemifield

Sperm dumping as a defense against meiotic drive

Sperm from Drosophila simulans that carry a sex-ratio distorter is preferentially lost from females' sperm-storage organs. This suggests that sperm dumping is a major factor affecting sperm competition in this species, and may have evolved in response to sex-ratio distorters

Optimization of the Penalty Parameter for the Dual-Wind Discontinuous Galerkin Methods on a Prototypical Second Order Pde.

A discontinuous Galerkin (DG) finite-element interior calculus is used as a common framework to describe various DG approximation methods for second- order elliptic problems. The dual-wind discontinuous Galerkin method (DWDG) has been shown to be stable and consistent for a wide range of penalty parameter values, including zero, for second order elliptic problems under certain mesh conditions. In this presentation, we will present the results of numerical experiments on various second order elliptic problems with varying penalty parameters that show the choice of zero for the penalty parameter is an optimal choice for application

The 2018 Provincial Election in New Brunswick

New Brunswick’s 2018 election produced a minority legislature, the first in a century. The major parties continue to decline in voter support, and two new parties now have a presence in the Assembly. The election brings New Brunswick’s electoral politics increasingly into the modern Canadian mainstream; one new caucus is the Greens. In other respects, the election made the old new again. The populist People’s Alliance gained three seats partly on the basis of criticism of bilingualism policy. The Alliance and the Progressive Conservatives, in an informal alliance to govern, are all but confined to the anglophone parts of the province, while the defeated Liberals have all their strength in the Acadian north-east. The campaign mattered, as did constitutional conventions.  The Liberals squandered a large lead in the polls, and the parties struggled to sort out the conventions of government formation

Eleven Principles of Effective Character Education

There is no single script for effective character education, but there are some important basic principles. The following eleven principles serve as criteria that schools and other groups can use to plan a character education effort and to evaluate available character education programs, books, and curriculum resources