Extended Holomorphic Anomaly in Gauge Theory

The partition function of an N=2 gauge theory in the Omega-background satisfies, for generic value of the parameter beta=-eps_1/eps_2, the, in general extended, but otherwise beta-independent, holomorphic anomaly equation of special geometry. Modularity together with the (beta-dependent) gap structure at the various singular loci in the moduli space completely fixes the holomorphic ambiguity, also when the extension is non-trivial. In some cases, the theory at the orbifold radius, corresponding to beta=2, can be identified with an "orientifold" of the theory at beta=1. The various connections give hints for embedding the structure into the topological string.Comment: 25 page

Finding Faint Intermediate-mass Black Holes in the Radio Band

We discuss the prospects for detecting faint intermediate-mass black holes, such as those predicted to exist in the cores of globular clusters and dwarf spheroidal galaxies. We briefly summarize the difficulties of stellar dynamical searches, then show that recently discovered relations between black hole mass, X-ray luminosity and radio luminosity imply that in most cases, these black holes should be more easily detected in the radio than in the X-rays. Finally, we show upper limits from some radio observations of globular clusters, and discuss the possibility that the radio source in the core of the Ursa Minor dwarf spheroidal galaxy might be a $\sim 10,000-100,000 M_\odot$ black hole.Comment: 10 pages, no figures, to appear in From X-ray Binaries to Quasars: Black Hole Accretion on All Mass Scales, ed. T. J. Maccarone, R. P. Fender, and L. C. Ho (Dordrecht: Kluwer

Supersymmetric Gauge Theories, Intersecting Branes and Free Fermions

We show that various holomorphic quantities in supersymmetric gauge theories can be conveniently computed by configurations of D4-branes and D6-branes. These D-branes intersect along a Riemann surface that is described by a holomorphic curve in a complex surface. The resulting I-brane carries two-dimensional chiral fermions on its world-volume. This system can be mapped directly to the topological string on a large class of non-compact Calabi-Yau manifolds. Inclusion of the string coupling constant corresponds to turning on a constant B-field on the complex surface, which makes this space non-commutative. Including all string loop corrections the free fermion theory is elegantly formulated in terms of holonomic D-modules that replace the classical holomorphic curve in the quantum case.Comment: 67 pages, 6 figure

Exact results for topological strings on resolved Y(p,q) singularities

We obtain exact results in \alpha' for open and closed A-model topological string amplitudes on a large class of toric Calabi-Yau threefolds by using their correspondence with five dimensional gauge theories. The toric Calabi-Yau's that we analyze are obtained as minimal resolution of cones over Y(p,q) manifolds and give rise via M-theory compactification to SU(p) gauge theories on R^4 x S^1. As an application we present a detailed study of the local F_2 case and compute open and closed genus zero Gromov-Witten invariants of the C^3/Z_4 orbifold. We also display the modular structure of the topological wave function and give predictions for higher genus amplitudes.The mirror curve in this case is the spectral curve of the relativistic A_1 Toda chain. Our results also indicate the existence of a wider class of relativistic integrable systems associated to generic Y(p,q) geometries.Comment: 54 pages, 10 figures; typos corrected, new section added. Version accepted for publication on Communications in Mathematical Physic

Randomized placebo- and active-controlled study of desvenlafaxine for menopausal vasomotor symptoms

ArticleObjective To evaluate the efficacy and safety of desvenlafaxine (administered as desvenlafaxine succinate) vs. tibolone and placebo for menopausal vasomotor symptoms and the incidence of uterine bleeding. Methods This 12-week double-blind randomized controlled trial was conducted at 35 sites in Europe two sites in South Africa and one site in Mexico. Postmenopausal women with ≥50 moderate or severe hot flushes per week (n = 485) were randomized to desvenlafaxine 100 mg/day tibolone 2.5 mg/day or placebo. Reduction in the average daily number of moderate and severe hot flushes at weeks 4 and 12 (primary endpoint) was evaluated using analysis of covariance. Safety assessments included incidence of uterine bleeding adverse events laboratory values and vital signs. Results At week 12 no statistically significant difference was observed in reduction of the average daily number of moderate and severe hot flushes for desvenlafaxine (-5.78) vs. placebo (-5.82; p = 0.921) although time to 50% reduction was significantly less than placebo (13 vs. 26 days p = 0.006). Hot flush reduction with tibolone (-8.21) was significantly greater than placebo (p < 0.001). Nausea was the most common adverse event with desvenlafaxine was generally mild to moderate and resolved within the first 2 weeks. Significantly more subjects experienced bleeding with tibolone (23%) vs. desvenlafaxine (12%; p < 0.024) or placebo (9%; p < 0.001). Conclusions Desvenlafaxine did not separate from placebo in reducing the number of moderate to severe hot flushes at week 12 although it did allow women to achieve 50% reduction sooner than placebo. Tibolone did separate from placebo but with smaller than expected effect. The placebo effect was high (57%). Adverse drug reactions were consistent with the known safety profile of desvenlafaxine and significantly more women who received tibolone experienced episodes of bleeding compared with women who received desvenlafaxine or placebo. © 2012 International Menopause Society