The food consumption to biomass ratio (C) is one of the most important population parameters in ecosystem modelling because its quantifies the interactions between predator and prey. Existing models for estimating C in fish populations are per-recruit cohort models or empirical models, valid only for stationary populations. Moreover, empirical models lack theoretical support. Here we develop a ...

The following article is the verbatim text of a report based on research funded by the Social Security Administration and the National Institute of Child Health and Human Development to the Rand Corporation. The report looks at changing fertility rates in the United States and their implications for future population size and age distributions. An economic model of fertility rate is used to exp...

To assess the influence of storage dynamics and nonlinearities in hydrological connectivity on time-variant stream water ages, we used a new long-term record of daily isotope measurements in precipitation and streamflow to calibrate and test a parsimonious tracer-aided runoff model. This can track tracers and the ages of water fluxes through and between conceptual stores in steeper hillslopes, ...

This paper presents annual indices of labour input adjusted for the age, education and gender distributions of the Irish workforce for the period 1999-2008. Growth in labour services is divided between the increase in hours and improvement in the productive quality of these hours. Improvement in labour quality, as proxied by education, age and gender, has added on average 0.7 percentage points ...

Preterm neonates are at higher risk of neurocognitive and neurosensory abnormalities. While numerous studies have looked at the effect of prematurity on brain anatomy, none to date have attempted to understand the relative pose of subcortical structures and to assess its potential as a biomarker of abnormal growth. Here, we perform the first relative pose analysis on a point distribution model ...

For some time now, it has been recognised that a major shift is occurring in the population age distributions of most motorised countries resulting in a growing number of older persons with an increasing need for mobility. It is expected that the mobility of older persons will become even more reliant on the motor vehicle as European countries in particular undergo transitions towards decentral...