Common visual problems in children with disability

Children with disability are at a substantially higher risk of visual impairment (VI) (10.5% compared with 0.16%) but also of ocular disorders of all types, including refractive errors and strabismus. The aetiology of VI in children with disability reflects that of the general population and includes cerebral VI, optic atrophy, as well as primary visual disorders such as retinal dystrophies and structural eye anomalies. VI and other potentially correctable ocular disorders may not be recognised without careful assessment and are frequently unidentified in children with complex needs. Although assessment may be more challenging than in other children, identifying these potential additional barriers to learning and development may be critical. There is a need to develop clearer guidelines, referral pathways and closer working between all professionals involved in the care of children with disability and visual disorders to improve our focus on the assessment of vision and outcomes for children with disability

Commentary on "Long-run risks and financial markets"

Financial markets ; Risk

Rational Expectations, the Real Rate of Interest, and the Natural Rate of Unemployment

macroeconomics, real rate interest, unemployment rate

"Rational Expectations": A Correction

macroeconomics, rational expectations, unemployment

R. F. testing of the third generation defense communication satellite

The approach taken to test a completed DSCS communications satellite on a system level is described. Areas to be described are measuring RF isolation of separate communications subsystems and a test method which insures that one RF subsystem does not interfere with another. In addition, the method of complying with MIL-STD-1541 in the area of demonstrating safety of electroexplosive devices in an RF field is discussed

Interest rate risk and other determinants of post WWII U.S. government debt/GDP dynamics

This paper uses a sequence of government budget constraints to motivate estimates of returns on the U.S. Federal government debt. Our estimates differ conceptually and quantitatively from the interest payments reported by the U.S. government. We use our estimates to account for contributions to the evolution of the debt-GDP ratio made by inflation, growth, and nominal returns paid on debts of different maturities.Holding period returns, capital gains, inflation, growth, debt- GDP ratio, government budget constraint