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We assume that the manifold with boundary, X, has a Spin_C-structure with spinor bundle S. Along the boundary, this structure agrees with the structure defined by an infinite order integrable almost complex structure and the metric is Kahler. The induced CR-structure on bX is integrable and either strictly pseudoconvex or strictly pseudoconcave. We assume that E->X is a complex vector bundle, which has an infinite order integrable complex structure along bX, compatible with that defined along bX. In this paper use boundary layer methods to prove subelliptic estimates for the twisted Spin_C- Dirac operator acting on sections on S\otimes E. We use boundary conditions that are modifications of the classical dbar-Neumann condition. These results are proved by using the extended Heisenberg calculus., Comment: To appear Annals of Math. 57 pages. Wrong file uploaded on previous attempt. The second revision fills a gap in the proof of Proposition 16

A unimodular complex surface is a complex 2-manifold X endowed with a holomorphic volume form. A strictly pseudoconvex real hypersurface M in X inherits not only a CR-structure but a canonical coframing as well. In this article, this canonical coframing on M is defined, its invariants are discussed and interpreted geometrically, and its basic properties are studied. A natural evolution equation for strictly pseudoconvex real hypersurfaces in unimodular complex surfaces is defined, some of its properties are discussed, and several examples are computed. The locally homogeneous examples are determined and used to illustrate various features of the geometry of the induced structure on the hypersurface., Comment: 34 pages

A joint generalization of real smooth as well of complex manifolds are the Cauchy-Riemann manifolds. The main objective of the paper is to inroduce a class of symmetric CR manifolds containing both classes of Riemannian and Hermitian symmetric spaces. It turns out that the classical requirement of isolated fixed points for the symmetries is no longer adequate, because it would imply the Levi-flatness. Among all symmetric CR-manifolds we distinguish a large subclass consisting of all Shilov boundaries of bounded symmetric domains. For this class we calculate the polynomial and the rational convex hulls Both hulls are canonically stratified into real-analytic CR-submanifolds such that the (unique) stratum of the highest dimension is complex for the polynomial and Levi-flat for the rational convex hull. It is also proved that the CR-functions extend continuously to the rational convex hull such that the extension is CR on every stratum., Comment: 24 pages, to appear in Advances in Mathematics