Ewens' sampling formula, the probability distribution of a configuration of alleles in a sample of genes under the infinitely-many-alleles model of mutation, is proved by a direct combinatorial argument. The distribution is extended to a model where the population size may vary back in time. The distribution of age-ordered frequencies in the population is also derived in the model, extending th...

We apply the method of principal component analysis to a sample of simple stellar population to select some age sensitive spectral indices. Besides the well-known age sensitive index, Hβ, we find some other spectral indices have great potential to determine the age of stellar population, such as G4300, Fe4383, C24668, and Mgb. In addition, we find these spectral indices sensitivity to age depen...

Cerebral language lateralization can be assessed in several ways. In healthy subjects, functional MRI (fMRI) during performance of a language task has evolved to be the most frequently applied method. Functional transcranial Doppler (fTCD) may provide a valid alternative, but has been used rarely. Both techniques have their own strengths and weaknesses and as a result may be applied in differen...

A climate-induced phenological mismatch between the timing of reproduction and the timing of food resource peaks is one of the key hypothesized effects of climate change on wildlife. Though supported as a mechanism of population decline in birds, few studies have investigated whether the same temperature increases that drive this mismatch have the potential to decrease energetic costs of growth...

This paper investigates the impact of economic growth and more specifically robust economic growth along with other macroeconomic determinants on poverty levels using both the U.S. official measure of poverty and an estimated time series of Sen indices of poverty. The results reveal that the period of robust economic expansion that the U.S. economy experienced during the 1990s did not have a si...

abstract objectives: radiomorphometric indices measured on simple radiographic images can be used for qualitative and quantitative assessment of bone. panoramic radiographic imaging can therefore assist dentists in early detection of osteoporosis in patients. considering the effect of ethnic and environmental factors on development of osteoporosis and absence of normal values of radiomorphometr...

This study presents a dynamical systems model for long-term scenarios of demand in the aviation sector and resultant emissions of CO2 and NOx. We analyze the dynamics of demand growth for aviation, particularly in the emerging markets of developing nations. A model for subsonic aviation emissions is presented that reflects the consequences of industry forecasts for improvement in aviation fuel ...

This study presents a dynamical systems model for long-term scenarios of demand in the aviation sector and resultant emissions of CO2 and NOx. We analyze the dynamics of demand growth for aviation, particularly in the emerging markets of developing nations. A model for subsonic aviation emissions is presented that reflects the consequences of industry forecasts for improvement in aviation fuel ...