String Theory on Warped AdS_3 and Virasoro Resonances

We investigate aspects of holographic duals to time-like warped AdS_3 space-times--which include G\"odel's universe--in string theory. Using worldsheet techniques similar to those that have been applied to AdS_3 backgrounds, we are able to identify space-time symmetry algebras that act on the dual boundary theory. In particular, we always find at least one Virasoro algebra with computable central charge. Interestingly, there exists a dense set of points in the moduli space of these models in which there is actually a second commuting Virasoro algebra, typically with different central charge than the first. We analyze the supersymmetry of the backgrounds, finding related enhancements, and comment on possible interpretations of these results. We also perform an asymptotic symmetry analysis at the level of supergravity, providing additional support for the worldsheet analysis.Comment: 24 pages + appendice

Hypertrophic Scarring and Keloids: Pathomechanisms and Current and Emerging Treatment Strategies

Excessive scars form as a result of aberrations of physiologic wound healing and may arise following any insult to the deep dermis. By causing pain, pruritus and contractures, excessive scarring significantly affects the patient’s quality of life, both physically and psychologically. Multiple studies on hypertrophic scar and keloid formation have been conducted for decades and have led to a plethora of therapeutic strategies to prevent or attenuate excessive scar formation. However, most therapeutic approaches remain clinically unsatisfactory, most likely owing to poor understanding of the complex mechanisms underlying the processes of scarring and wound contraction. In this review we summarize the current understanding of the pathophysiology underlying keloid and hypertrophic scar formation and discuss established treatments and novel therapeutic strategies