Let J be the Jacobian of a smooth curve C of genus g, and let A(J) be the ring of algebraic cycles modulo algebraic equivalence on J, tensored with $\mathbb{Q}$. We study in this paper the smallest $\mathbb{Q}$-vector subspace R of A(J) which contains C and is stable under the natural operations of A(J): intersection and Pontryagin products, pull back and push down under multiplication by integers. We prove that this ‘tautological subring’ is generated (over $\mathbb{Q}$) by the classes of the subvarieties $W_1=C,\ W_2=C + C, \dots ,W_{g-1}$. If C admits a morphism of degree d onto $\mathbb{P}^1$, we prove that the last d - 1 classes suffice.

Let X be a strongly pseudoconvex compact 3-dimensional CR manifolds which bounds a complex variety with isolated singularities in some C$^N$. The weighted dual graph of the exceptional set of the minimal good resolution of V is a CR invariant of X; in case X has a tranversal holomorphic S¹ action, we show that it is a complete topological invariant of except for two special cases. When X is a rational CR manifolds, we give explicit algebraic algorithms to compute the graph invariant in terms of the ring structure of [oplus ]$_k=0$$^$∞ m$^k$/m$^k+1$, where m is the maximal ideal of each singularity. An example is computed explicitly to demonstrate how the algorithms work.

In this paper it is shown that the computation of higher dimensional harmonic volume, defined in [1], can be reduced to Harris' computation in the onedimensional case (See [3]), so that higher dimensional harmonic volume may be computed essentially as an iterated integral. We then use this formula to produce a specific smooth curve , namely a specific double cover of the Fermat quartic, so that the image of the second symmetric product of in its Jacobian via the Abel-Jacobi map is algebraically inequivalent to the image of under the group involution on the Jacobian.