There is an urgent need to come up with a vaccine that will curtail the spread of HIV-1. To be successful, the scientific community must work in concert to develop sound strategies based on a deeper understanding of the virus. Significant technological advances are also required to overcome the unique obstacles posed by HIV-1. Some of the challenges we face in this endeavor are discussed here.
We study the connected regular graphs with four distinct eigenvalues. Properties Cheap Babyliss Hair Curlers
and feasibility conditions of the eigenvalues are found. Several examples, constructions and characterizations are given, as well as some uniqueness and nonexistence results.
A new type of hologram, double aperture rainbow hologram (DARH), which can be reconstructed by a 2-D largely extended white light source with much higher resolution than that of the conventional single slit rainbow hologram (SSRH), is suggested. Its principle is explained, the experimental results in good agreement with theoretical expectation are also given.
The square of a graph is obtained by Discount Ghd Hair Australia adding additional edges joining all pairs of vertices with distance two in the original graph. Pósa conjectured that if G is a simple graph on n vertices with minimum degree 2n/3, then G contains the square of a hamiltonian cycle. We show that Pósa's conjecture holds for graphs that in addition contain a maximal 4-clique.