This study of secular trend in Portugal has shown that a positive increment in height occurred in Portuguese 18year-old males between 1904 and 2000, and a secular trend in the age at menarche, towards an earliest age, also took place. Mean height increased 8.93 cm, from 1904 to 2000, when reached 172,13 cm. Besides that, in 2000, statistically significant differences (p ≤ 0.001) among the distr...

Lucas Engelhardt 1 does not point out anything incorrect in my “Capital-Based Theory of Secular Growth” (2009). Rather, he implicates me in a violation of Occam’s razor. My discussion of nonrivalry, external effects, and intangible capital contains, but obscures, the fundamental ingredient for secular growth: nondepreciating capital. Engelhardt purports to demonstrate how nondepreciating capita...

BACKGROUND Secular trends in cardiovascular risk factors have been described, but few studies have examined simultaneously the effects of both ageing and secular trends within the same cohort. METHODS Development of cardiovascular risk factors over the past three decades was analysed using serial measurements from 10 308 participants aged from 35 to 80 years over 25 years of follow-up from fi...

Since the 19th century there have been clearly documented secular trends to increasing adult height in most European countries, with current rates of 10-30 mm/decade. Over the same period menarcheal age has also fallen steeply, but has now stabilized at approximately 13 years and may be rising again. Height trends tend to be greater in childhood than in adulthood due to the associated advance i...

The homotopy analysis method HAM is employed to propose an approach for solving the nonlinear dynamical system of an electrostatically actuated micro-cantilever in MEMS. There are two relative merits of the presented HAM compared with some usual procedures of the HAM. First, a new auxiliary linear operator is constructed. This operator makes it unnecessary to eliminate any secular terms. Furthe...

The Chinese ancient accounts of timing observations of 48 lunar eclipses and the secular variation of the Earth's spin speed are discussed. A series of T expressing the secular deceleration of the Earth's rotation was obtained. The average increase rate of length of the day is about 1.5 milliseconds per century.

It is found that a previously thought-to-be well established result of density wave theory, that there is no interaction between a quasistationary spiral density wave and the basic state (i.e. the axisymmetric part) of the galactic disk, is in fact false. When solved as a nonlinear and globally self-consistent problem, the presence of non-axisymmetric patterns such as spirals or bars is shown t...

This paper provides a review of the recent literature on some aspects of secular trends in Western countries. In particular, we discuss height variation, mainly on the basis of conscript data. There are still large height differences between European countries, and there is a marked trend for the tallest conscripts to be in northern Europe and the shortest ones in the southern part of the conti...

Symplectic methods for Hamiltonian systems are known to have favourable properties concerning long-time integrations (no secular terms in the error of the energy integral, linear error growth in the angle variables instead of quadratic growth, correct qualitative behaviour) if they are applied with constant step sizes, while all of these properties are lost in a standard variable step size impl...