What is Colorism?

Analyze any advertising campaign colorism, dark-skinned, skin lightening, skin bleaching or notice the types of people represented in the media and on television and one major conclusion will be made clear -- Colorism is a prevalent issue worldwide. When the complexity of colorism transpires within a race it causes an even greater societal struggle, making it almost impossible to eliminate

An appraisal of the molecular model for the vk centre

The Vk centre in halide crystals is often described in terms of an X2− molecule ion. Recent molecular calculations for the halogen molecule negative ions have enabled a detailed comparison to be made between the theoretical anion and the results from optical and spin resonance studies on the crystals. The optical absorption line widths are naturally dependant on the host lattice, but the excitation energies and spin resonance constants may be readily interpreted in terms of the molecule. Certain anomalies in the spin resonance data for the heteronuclear defects, in particular ClI− and BrI−, show that the simple wavefunction constructed from “s” and “p” atomic orbitals does not adequately describe the polarisation of the large halogen atoms, and a more flexible wavefunction will be needed to calculate the spin resonance constants for these ions

QUENCHING OF LUMINESCENCE IN SEMICONDUCTORS BY CHARGED DEFECTS

Charged point defects and dislocations create internal electric fields that can prevent the binding of carriers to luminescent centres such as N in GaP. The authors calculate the distribution of fields present in a semiconductor and its effect on the lifetime of an electron trapped at a localised impurity. The results show a decrease in the fraction of effective luminescent centres with increasing concentration of ionised donors and acceptors. Both unscreened dislocations and those with a compensating atmosphere of oppositely charged point defects are considered and the calculations show dark regions around them, as observed

Receiving, or ‘Adopting’, Donated Embryos to Have Children: Parents Narrate and Draw Kinship Boundaries

Existing research suggests that embryo donation (ED) may be seen as similar to adoption by those who donate or receive embryos, or it may not. Our qualitative study explored whether having a child via embryo donation initiated kinship connections between embryo donor and recipient families as interpreted by recipient parents. Interviews were conducted with five parents from four families whose child(ren) had been born via embryo donation. All four families had an open-contact relationship set up with the couples who donated their embryos through an agency in the USA. Narrative thematic analysis of interview data and visual family map drawings were used to explore kinship conceptualizations. We conclude that the dilemma experienced by parents who have a child via embryo donation is to decide how to reconcile their child’s different genetic heritage, when gestation and upbringing both clearly boundary family membership solely within the recipient family. While some families were still struggling with this dilemma, one solution embarked upon by some parents when drawing their family map was to expand family membership, not only on the basis of genetics, but also via an appreciation of shared family and community values too

QUADRUPOLE SPLITTING OF MOSSBAUER LINES DUE TO DEFECTS IN CO0

The Fe3+ lines observed in CoO Mossbauer sources may arise from the decay of Co3+ ions associated with cation vacancies in the crystal. These defects produce an electric-field gradient that causes a quadrupole splitting of the resonance line and that can, in principle, distinguish between different types of defects. The calculation of the quadrupole splitting at Fe2+ and Fe3+ sites near various vacancy clusters includes the relaxation of the lattice about the defect. This lattice polarisation and distortion is shown to be extremely important, since simple calculations based on perfect ion positions give very different field gradients at neighbouring sites. The results compared with the experiments available and the quadrupole splittings observed are close to those predicted by a vacancy model

Mechanism related to the lateral rectus muscle capable of retracting the outer canthus of the eye

This is the author's PDF version of an article published in British journal of ophthamology© 1994. The definitive version is available at bjo.bmj.comThis article discusses a case report of a fibromembranous slip arising from the belly of the left lateral rectus muscle which was discovered in a male subject

Does feedback help or hinder star formation? The effect of photoionisation on star formation in Giant Molecular Clouds

We investigated the effect of photoionising feedback inside turbulent star-forming clouds, comparing the resultant star formation in both idealised profiles and more realistic cloud structures drawn from a global galaxy simulation. We performed a series of numerical simulations which compared the effect of star formation alone, photoionisation and photoionisation plus supernovae feedback. In the idealised cloud, photoionisation suppresses gas fragmentation at early times, resulting in the formation of more massive stars and an increase in the star formation efficiency. At later times, the dispersal of the dense gas causes the radiative feedback effect to switch from positive to negative as the star formation efficiency drops. In the cloud extracted from the global simulation, the initial cloud is heavily fragmented prior to the stellar feedback beginning and is largely structurally unaffected by the late injection of radiation energy. The result is a suppression of the star formation. We conclude that the efficiency of feedback is heavily dependent on the gas structure, with negative feedback dominating when the density is high.Comment: Accepted to MNRA