TTˉT{\bar T} and Holography

In recent years, there have been two independent but related developments in the study of irrelevant deformations in two dimensional quantum field theories (QFTs). The first development is the deformation of a two dimensional QFT by the determinant of the energy momentum stress tensor, commonly referred to as $T{\bar T}$ deformation. The second development is in two dimensional holographic field theories which are dual to string theory in asymptotically Anti-de Sitter (AdS) spacetimes. In this latter development, the deformation is commonly referred to as single-trace $T{\bar T}$ deformation. The single-trace $T{\bar T}$ deformation corresponds in the bulk to a string background that interpolates between AdS spacetime in the infrared (IR) and a linear dilaton spacetime (vacuum of little string theory (LST)) in the ultraviolet (UV). It serves as a useful tool and guide to better understand and explore holography in asymptotically AdS and non-AdS spacetimes in a controlled setting. In particular, it is useful to gain insights into holography in flat spacetimes. The dissertation is devoted to the study of single-trace $T{\bar T}$ deformation and its single-trace generalizations in theories with $U(1)$ currents, namely $J\bar T$ and $T\bar J$ deformations, in the context of gauge/gravity duality. In the dissertation I present new results in the study of holography in asymptotically non-AdS spacetimes. I discuss two point correlation functions in single-trace $T{\bar T}$ deformation, and entanglement entropy and entropic $c$-function in single-trace $T{\bar T}$, $J\bar T$ and $T\bar J$ deformations. I show that two point functions in position space have both real parts and imaginary parts. I also show that the imaginary parts are non-perturbative. The imaginary parts correspond in momentum space to branch cuts, which signal non-locality. I obtain exact result for entanglement entropy associated with a spatial region of finite size. I also show that in the UV for a particular combination of the deformation couplings the leading order dependence of the entanglement entropy on the size is given by a square root but not logarithmic function. Such power law dependence of the entanglement entropy on the size is quite distinct and interesting. I also give exact result for the entropic $c$-function and show that it is regularization schemes independent, positive and monotonic, which are similar to the behaviors observed in conventional local QFTs. I also discuss its distinctive features in the UV

Prospective Audit of Avoidable Factors in Institutional Stillbirths and Early Neonatal Deaths at Tikur Anbessa Hospital in Addis Ababa, Ethiopia

Mortality audits are being used with increasing frequency to improve health outcomes by pinpointing precisely where deficiencies in clinical care exist. We conducted a prospective audit of stillbirths and early neonatal deaths at Tikur Anbessa Hospital in Addis Ababa, Ethiopia, as part of a broader initiative to reduce perinatal mortality in the labor room and neonatal intensive care unit. Out of 1,225 deliveries that took place during the six-month study period, there were 30 stillbirths and 31 early neonatal deaths (PMR 50/1,000). A multi-disciplinary Audit Team was established and convened monthly to review standardized data collection forms that were completed for each death. It was determined that avoidable factors were present in 70% of perinatal deaths. Health worker-related factors were the most common avoidable factors identified (accounting for 84% of avoidable factors identified), followed by patient-related factors (11%) and administrative-related factors (5%). Based on the study findings, quality improvement programs that target gaps in care are being implemented on the hospital’s labor room and in the neonatal intensive care unit.Keywords: Perinatal mortality, Clinical audit, Ethiopia, Developing Countries, Stillbirt

Mental, neurologic, and substance use (MNS) disorders among street homeless people in Ethiopia

Abstract Background About 25–60% of the homeless population is reported to have some form of mental disorder. To our knowledge, there are no studies aimed at the screening, diagnosis, treatment, care, rehabilitation, and support of homeless people with mental, neurologic, and substance use (MNS) disorders in general in Ethiopia. This is the first study of its kind in Africa which was aimed at screening, diagnosis, care, treatment, rehabilitation, and support of homeless individuals with possible MNS disorder. Methods Community-based survey was conducted from January to March 2015. Homeless people who had overt and observable psychopathology and positive for screening instruments (SRQ20, ASSIST, and PSQ) were involved in the survey and further assessed for possible diagnosis by structured clinical interview for DSM-IV diagnoses and international diagnostic criteria for seizure disorders for possible involvement in care, treatment, rehabilitation services, support, and training. The Statistical Program for Social Science (SPSS version 20) was used for data entry, clearance, and analyses. Results A total of 456 homeless people were involved in the survey. Majority of the participants were male (n = 402; 88.16%). Most of the homeless participants had migrated into Addis Ababa from elsewhere in Ethiopia and Eritrea (62.50%). Mental, neurologic, and substance use disorders resulted to be common problems in the study participants (92.11%; n = 420). Most of the participants with mental, neurologic, and substance use disorders (85.29%; n = 354) had psychotic disorders. Most of those with psychosis had schizophrenia (77.40%; n = 274). Almost all of the participants had a history of substance use (93.20%; n = 425) and about one in ten individuals had substance use disorders (10.54%; n = 48). Most of the participants with substance use disorder had comorbid other mental and neurologic disorders (83.33%; n = 40). Conclusion and recommendation Mental, neurologic, and substance use disorders are common (92.11%) among street homeless people in Ethiopia. The development of centers for care, treatment, rehabilitation, and support of homeless people with mental, neurologic, and substance use disorders is warranted. In addition, it is necessary to improve the accessibility of mental health services and promote better integration between mental and primary health care services, as a means to offer a better general care and to possibly prevent homelessness among mentally ill