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

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

Formation of an embryonic supermassive star in the first galaxy

We studied the gravitational collapse of a warm (~8000 K) primordial-gas cloud as a candidate progenitor for a supermassive star (SMS; >10^5 Msun) using a three-dimensional hydrodynamical simulation, including all the relevant cooling processes of both H_2 and H, which can potentially induce cloud fragmentation. This is the first simulation of this kind to resolve protostar formation. We find that the cloud undergoes runaway collapse without a major episode of fragmentation. Although the H_2 fraction jumps by a large factor via the three-body reaction at ~10^-13 g/cm^3, its cooling remains inefficient due to the optical thickness, and the temperature remains >3000 K. When the central core of the cloud becomes opaque to continuum radiation at ~10^-8 g/cm^3, a hydrostatic protostar with ~0.2 Msun is formed. The protostar grows to the mass ~1 Msun and the radius ~2 AU within ~1 yr via rapid accretion of dense filamentary flows. With high accretion rate ~2 Msun/yr, the protostar is expected to turn into a SMS within its lifetime, eventually collapsing to a seed for the supermassive black hole observed in the early Universe at z~7.Comment: 6 pages, 6 figures, Accepted for publication in MNRA

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

Star Formation in Disk Galaxies. II. The Effect of Star Formation and Photoelectric Heating on the Formation and Evolution of Giant Molecular Clouds

We investigate the effect of star formation and diffuse photoelectric heating on the properties of giant molecular clouds (GMCs) formed in high resolution (~< 10 pc) global (~ 20 kpc) simulations of isolated Milky Way-type galaxy disks. The clouds are formed through gravitational fragmentation and structures with densities n_H>=100cm^-3 are identified as GMCs. Between 1000-1500 clouds are created in the simulations with masses M > 10^5 Msolar and 180-240 with masses M > 10^6 Msolar in agreement with estimates of the Milky Way's population. We find that the effect of photoelectric heating is to suppress the fragmentation of the ISM, resulting in a filamentary structure in the warm gas surrounding clouds. This environment suppresses the formation of a retrograde rotating cloud population, with 88% of the clouds rotating prograde with respect to the galaxy after 300 Myr. The diffuse heating also reduces the initial star formation rate, slowing the conversation of gas into stars. We therefore conclude that the interstellar environment plays an important role in the GMCs evolution. Our clouds live between 0-20 Myr with a high infant mortality (t' < 3 Myr) due to cloud mergers and star formation. Other properties, including distributions of mass, size and surface density agree well with observations. Collisions between our clouds are common, occurring at a rate of ~1/4 of the orbital period. It is not clear whether such collisions trigger or suppress star formation at our current resolution. Our star formation rate is a factor of 10 higher than observations in local galaxies. This is likely due to the absence of localized feedback in our models.Comment: 25 pages. 18 figures. Accepted for publication in Ap