The potential dependence of second-to-fourth digit ratio (2D:4D) on latitude has been discussed in recent papers in this journal (Hurd & van Anders, 2007; Loehlin, McFadden, Medland, & Martin, 2006, 2007). Such an association was first suggested by Manning (2002), who proposed that 2D:4D was highest at intermediate latitudes and lowest at the equator and at high latitudes. In their Fig. 1, Hurd...

The Architecture, Engineering and Construction industry is under constant pressure to increase the quality and speed of its production delivery processes. This is due to the mutual competition amongst the industry's constituents and the growing demands of clients who expect faster delivery and higher quality. This has encouraged the AEC community to explore alternative ways in conducting projec...

We discuss the dynamics of a particular two-dimensional (2D) physical system in the four dimensional (4D) (non-)commutative phase space by exploiting the consistent Hamiltonian and Lagrangian formalisms based on the symplectic structures defined on the 4D (non-)commutative cotangent manifolds. The noncommutativity exists equivalently in the coordinate or the momentum planes embedded in the 4D c...

We discuss the dynamics of a particular two-dimensional (2D) physical system in the four dimensional (4D) (non-)commutative phase space by exploiting the consistent Hamiltonian and Lagrangian formalisms based on the symplectic structures defined on the 4D (non-)commutative cotangent manifolds. The noncommutativity exists equivalently in the coordinate or the momentum planes embedded in the 4D c...

One of the challenges in 4D math visualization is to develop an interactive and integrated computational environment to quick-prototype, simulate, and experiment with the abstract mathematical concepts. We have investigated several areas in 4D visualization, including 4D surface rendering, various user interface elements to manipulate mathematical objects in the higherdimensional space, and phy...

Experiences from projects utilizing 4D have been promising. Several companies together with researchers have seen 4D applications as potential products for lucrative business. The promising business prospects have resulted in numerous more and less intuitive attempts to develop such products. This paper draws commonalities from various approaches and reviews 4D applications from the viewpoint o...

It has been suggested that autism may arise as the result of exposure to high concentrations of prenatal testosterone. There is evidence that the ratio of the lengths of the 2nd and 4th digit (2D:4D) may be negatively correlated with prenatal testosterone. We measured 2D:4D in 95 families recruited via the National Autistic Society, UK. The sample comprised a total 72 children with autism (62 m...

Digit ratio (2D:4D) denotes the relative length of the second and fourth digits. This ratio is considered to be a biomarker of the balance between fetal testosterone (T) and estrogen (E) in a narrow window of early ontogeny. Evidence for this assertion is derived from direct and indirect measures of prenatal hormonal exposure (in experimental animals, via amniotic fluid samples and in the study...