Long String Scattering in c = 1 String Theory

We study the scattering of long strings in c = 1 string theory, both in the worldsheet description and in the non-singlet sector of the dual matrix quantum mechanics. From the worldsheet perspective, the scattering amplitudes of long strings are obtained from a decoupling limit of open strings amplitudes on FZZT branes, which we compute by integrating Virasoro conformal blocks along with structure constants of boundary Liouville theory. In particular, we study the tree level amplitudes of (1) a long string decaying by emitting a closed string, and (2) the scattering of a pair of long strings. We show that they are indeed well defined as limits of open string amplitudes, and that our results are in striking numerical agreement with computations in the adjoint and bi-adjoint sectors of the dual matrix model (based on proposals of Maldacena and solutions due to Fidkowski), thereby providing strong evidence of the duality.Comment: 42 pages, 18 figure

The c=1 String Theory S-Matrix Revisited

We revisit the perturbative S-matrix of c=1 string theory from the worldsheet perspective. We clarify the origin of the leg pole factors, the non-analyticity of the string amplitudes, and the validity as well as limitations of earlier computations based on resonance momenta. We compute the tree level 4-point amplitude and the genus one 2-point reflection amplitude by numerically integrating Virasoro conformal blocks with DOZZ structure constants on the sphere and on the torus, with sufficiently generic complex Liouville momenta, and find agreement with known answers from the c=1 matrix model.Comment: 32 pages, 7 figures; footnote and references added, typos correcte

Pancreatic pseudocyst eroding into the splenoportal venous confluence and mimicking an arterial aneurysm

We report the case of a 62-year-old man with chronic pancreatitis who presented with increasing abdominal pain. Sonography, magnetic resonance imaging, contrast-enhanced computed tomography, and ultimately catheter angiography demonstrated a pancreatic pseudocyst that had eroded into the splenoportal venous confluence, mimicking an arterial aneurysm. The diagnostic was confirmed at the time of surgical treatment. This case demonstrates the use of imaging to diagnose complications of pancreatitis, and the difficulty of distinguishing an eroding pseudocyst from an arterial aneurysm

Characterization in bi-parameter space of a non-ideal oscillator

The authors thank scientific agencies CAPES, CNPq (112952/2015-1), and FAPESP (2011/ 19269-11). M. S. Baptista also thanks EPSRC (EP/I03 2606/1).Peer reviewedPostprin

The S-Matrix of 2D Type 0B String Theory Part 2: D-Instanton Effects

We study the effect of D-instantons on closed string scattering amplitudes in the two-dimensional type 0B string theory from the worldsheet perspective. We find that the contribution from a pair of D-instanton and anti-D-instanton to the closed string reflection amplitude, with a suitable contour prescription for the integration over the D-instanton moduli space, agrees with the corresponding leading non-perturbative corrections in the proposed dual matrix quantum mechanics. This analysis is further extended to thermal observables defined at finite temperature. The infrared divergence in charged processes is understood through the measure factor for charged D-instantons, and can be treated with spacetime dimensional regularization.Comment: 30 pages, 3 figures, 1 tabl

Prevalence of Bacterial Vaginosis and Associated Factors among Pregnant Women Attending at Bugando Medical Centre, Mwanza, Tanzania

Bacterial vaginosis (BV) is an extremely common reproductive tract condition worldwide with reported high prevalence among African population. Factors associated with this condition include preterm labour, premature rupture of membranes, preterm delivery and possibly spontaneous abortion. Nevertheless, antenatal screening and treatment is not routinely available in most poor-resource countries including Tanzania. A cross-sectional descriptive study was conducted among delivering women at Bugando Medical Centre (BMC), Mwanza, Tanzania to determine the magnitude of the BV using the Nugent’s criteria and to document factors associated with the condition. A total of 284 women who presented for delivery at BMC labour ward from February to March 2011 were recruited into the study. For each consented women, a vaginal swab was taken, samples collected tested and a Nugent’s score of at least seven indicated bacterial vaginosis. Overall, bacterial vaginosis was diagnosed in 28.5% (n=81) of all participants. Gardnerella was the commonest morphotypes found in approximately 66.2% (n=188) of all participants while 11.6% (33 participants) had Mobilincus. There were no evidence for the association between bacterial vaginosis having formal education, (OR, 1.42[95%CI, 0.29-6.97; p=0.667]). Urban residence (OR, 1.29 [95% CI, 0.76-2.19; p=0.352]), ever delivered before (OR 0.66[95%CI, 0.39-1.12; p=0.126]), vaginal practice to enhance dry sex (OR, 1.16[95%CI, 0.43-3.17; p=0.768]) or wet sex (OR 1.31[95%CI, 0.46-3.7; p=0.613]), gestation age less than 37 weeks (OR 0.82[95%CI, 0.45-1.51; p=0.534]) and HIV infection (OR 0.90[95%CI, 0.28-2.92; p=0.863]) were not associated with bacterial vaginosis. Bacterial vaginosis is common among women delivering at Bugando Medical Centre and more studies to include antenatal clinic attendees initiating care are required to reliably document the magnitude the condition