150 and Counting

Canada 150

As we put 2017 behind us, I am dedicating this editorial to the celebration of Canada’s 150 birthday. I was fortunate to be in Ottawa for the month of August where I took in several Canada 150 events and displays, the most memorable and inspiring being MosaïCanada in Gatineau (created by the world famous Mosaïcultures internationales de Montréal http://english.mosaicanada.ca/). So impressed and...

Curve Counting and Instanton Counting

Intuitively, in four-dimensional gauge theories one counts instantons, and in twodimensional string theory one counts holomorphic curves. These correspond to the instanton counting and curve counting in the title. There is no obvious connection between them, but a remarkable physical idea called geometric engineering [9, 10, 11] dictates that they are indeed related. More precisely, the generat...

On Counting Polynomials of Some Nanostructures

The Omega polynomial(x) was recently proposed by Diudea, based on the length of strips in given graph G. The Sadhana polynomial has been defined to evaluate the Sadhana index of a molecular graph. The PI polynomial is another molecular descriptor. In this paper we compute these three polynomials for some infinite classes of nanostructures.

William Osler at 150.

Neandertals...150 years later.

The place of Neandertals in modern human emergence has been a subject of debate since the first recognized Neandertal skeleton was discovered in 1856. This paper presents an overview of morphological, archaeological, and genetic evidence commonly used in discussions of Neandertals and their evolutionary significance. A brief historical sketch of the argument provides insight into the changing v...