Medicine and Health Sciences Commons^™

Noise, Delays, And Resonance In A Neural Network, Austin Quan

HMC Senior Theses

A stochastic-delay differential equation (SDDE) model of a small neural network with recurrent inhibition is presented and analyzed. The model exhibits unexpected transient behavior: oscillations that occur at the boundary of the basins of attraction when the system is bistable. These are known as delay-induced transitory oscillations (DITOs). This behavior is analyzed in the context of stochastic resonance, an unintuitive, though widely researched phenomenon in physical bistable systems where noise can play in constructive role in strengthening an input signal. A method for modeling the dynamics using a probabilistic three-state model is proposed, and supported with numerical evidence. The potential …

Preventing Mother-To-Child Transmission Of Human Immunodeficiency Virus-1 (Hiv-1): Effects Of Intrapartum And Neonatal Single-Dose Nevirapine Prophylaxis And Subsequent Hiv-1 Drug Resistance At Antiretroviral Treatment Initiation, Amanda L. Harmon

CMC Senior Theses

The prevention of mother-to-child transmission is one of the most powerful tools in human immunodeficiency virus type 1 (HIV-1) prevention and has huge potential to improve both maternal and child health. In the absence of any preventative measures, infants born to and breastfed by their HIV-positive mothers have roughly a one-in-three chance of acquiring the infection themselves. HIV can be passed on from mother-to-child during pregnancy, during labor and delivery, and even after during breastfeeding.

Intrapartum and neonatal single-dose nevirapine (sd-NVP) is the foundation of preventing mother-to-child transmission in lower resource settings where it has been used alone or as …