Upper bounds for the writhing of knots and the helicity of vector fields ; The automorphism group of a free group is not subgroup separable ; Configuration spaces and braid groups on graphs in robotics ; Alternate discreteness tests ; Intersection-number operators for curves on discs and Chebyshev polynomials ; Implicit function theorem over free groups and genus problem ; On the degree of the Kauffman polynomial of a tangle decomposition ; Knot invariants from counting periodic points ; Random walk on knot diagrams, colored Jones polynomial and Ihara-Selberg zeta function ; Some applications of a multiplicative structure on simple loops in surfaces ; Closed braids and Heegaard splittings ; Homotopy and q-homotopy skein modules of 3-manifolds: An example in algebra Situs ; On knot invariants which are not of finite type