The Cosmic Radio and Infrared Backgrounds Connection

We use the radio-infrared (IR) flux correlation bet ween star-forming galaxies in the local universe to derive a simple analytical expression between the intensity of the IR background and the brightness t emperature of the radio background. This relation i s insensitive to the star formation history of the galaxies that produce the cosmic IR background (CIB). We use the observed CIB intensity to constrain t he cosmic star formation history, and the relation between the CIB and the cosmic radio background (CR B) to constrain the relative contribution of star-f orming galaxies to the CRB. Current limits on the C IB intensity predict a 178 MHz brightness temperature of ~18+-9 K, about half of the 37+-8 K inferred for an isotropic radio component. This suggests that s tar-forming galaxies and AGN contribute about equal ly to the CRB intensity at that frequency.Comment: Accepted for publication in the ApJ (14 pages + 3 embedded figures

Maternal Expression Relaxes Constraint on Innovation of the Anterior Determinant, bicoid

The origin of evolutionary novelty is believed to involve both positive selection and relaxed developmental constraint. In flies, the redesign of anterior patterning during embryogenesis is a major developmental innovation and the rapidly evolving Hox gene, bicoid (bcd), plays a critical role. We report evidence for relaxation of selective constraint acting on bicoid as a result of its maternal pattern of gene expression. Evolutionary theory predicts 2-fold greater sequence diversity for maternal effect genes than for zygotically expressed genes, because natural selection is only half as effective acting on autosomal genes expressed in one sex as it is on genes expressed in both sexes. We sample an individual from ten populations of Drosophila melanogaster and nine populations of D. simulans for polymorphism in the tandem gene duplicates bcd, which is maternally expressed, and zerknüllt (zen), which is zygotically expressed. In both species, we find the ratio of bcd to zen nucleotide diversity to be two or more in the coding regions but one in the noncoding regions, providing the first quantitative support for the theoretical prediction of relaxed selective constraint on maternal-effect genes resulting from sex-limited expression. Our results suggest that the accelerated rate of evolution observed for bcd is owing, at least partly, to variation generated by relaxed selective constraint

State of the World's Fathers: 2015

Fathers' involvement in their children's lives has been linked to higher cognitive development and school achievement, better mental health for boys and girls, and lower rates of delinquency in sons. Studies in multiple countries have shown that fathers' interaction is important for the development of empathy and social skills in sons and daughters.The SOWF report states that to achieve full gender equality and maximum wellbeing for children, we must move beyond rigid, limiting definitions of fatherhood and motherhood. This is not just a question of encouraging men to be nurturing and caring but rather an issue of social and economic justice. The report states that changes are needed in policies, in systems and institutions, among service providers, within programming and within data collection and analysis efforts. A lack of supportive policies such as paternity leave for new fathers helps cause an imbalance between mothers and fathers. This causes women to miss out on opportunities for work and income, children to miss out on having an involved father, and men to miss out on the positive benefits of involved fatherhood

Computerised tomography indices of raised intracranial pressure and traumatic brain injury severity in a New Zealand sample

After traumatic brain injury (TBI) complex cellular and biochemical processes occur¹ including changes in blood flow and oxygenation of the brain; cerebral swelling; and raised intracranial pressure (ICP).² This can dramatically worsen the damage³ and contributes to mortality

Sulphur and Carbon Isotopes as Tracers of Past Sub-seafloor Microbial Activity

Microbial life below the seafloor has changed over geological time, but these changes are often not obvious, as they are not recorded in the sediment. Sulphur (S) isotope values in pyrite extracted from a Plio- to Holocene sequence of the Peru Margin (Ocean Drilling Program, ODP, Site 1229) show a down-core pattern that correlates with the pattern of carbon (C) isotopes in diagenetic dolomite. Early formation of the pyrite is indicated by the mineralogical composition of iron, showing a high degree of pyritization throughout the sedimentary sequence. Hence, the S-record could not have been substantially overprinted by later pyrite formation. The S- and C-isotope profiles show, thus, evidence for two episodes of enhanced microbial methane production with a very shallow sulphate-methane transition zone. The events of high activity are correlated with zones of elevated organic C content in the stratigraphic sequence. Our results demonstrate how isotopic signatures preserved in diagenetic mineral phases provide information on changes of past biogeochemical activity in a dynamic sub-seafloor biosphere