Self-exciting spatio-temporal statistical models for count data with applications to modeling the spread of violence

In this dissertation we provide statistical models and inferential techniques for analyzing the number of violent or criminal events as they evolve over space and time. Our research focuses on a class of models we refer to as self-exciting spatio-temporal models. These are a class of parametric models that allow for dependence in a latent structure as well as dependence in the data model combining what is sometimes referred to as observation driven and parameter driven models. This class of models arise from straight-forward assumptions on how violence or crime evolves over space and time and has use in the statistical modeling of situations where there is an expected repeat or near-repeat victimization. In Chapter 2 we present the spatially correlated self-exciting model and the reaction-diffusion self-exciting model to analyze the number of violent events in different regions in Iraq. We also demonstrate how Laplace approximations can be used to conduct efficient Bayesian inference. We further show how the choice of the latent structure matters in this problem. In Chapter 3 we generalize the spatially correlated self-exciting model and show how it extends the classic integer generalized auto-regressive conditionally heteroskedastic, or INGARCH, model to account for spatial correlation and improves the second order properties of the INGARCH model. We refer to this new class of models as the spatially correlated INGARCH, or SPINGARCH, model. We show how the spatially correlated self-exciting model is similar to the SPINGARCH(0,1) model. Finally in Chapter 4 we present a fast extended Laplace approximation algorithm for fitting the SPINGARCH(0,1) model demonstrating empirically how the extended Laplace approximation method reduces a bias that exists in the Laplace approximation method while performing much quicker than Markov Chain Monte Carlo approaches

Novel Glass Material with Low Loss and Permittivity for 5G/6G Integrated Circuits

A new borosilicate glass with lower loss and permittivity than any commercial glass has been proposed in this contribution as a substrate or interposer for mm-wave and THz integrated electronics. The glass is composed of a microstructure enclosing high-purity boron rich areas and silicon rich areas. This phase-separated areas are several orders of magnitude smaller than the wavelength at 1 THz

EU Simulations and Engagement: Motivating Greater Interest in European Union Politics

While the effects of simulation based courses on the knowledge of participating students may be marginal in relation to standard lecture and discussion-based courses, this paper argues that the greatest leverage is gained by increasing participating students’ level of interest in the subject of study and in politics more broadly. Participants tend to become increasingly absorbed in their roles and in the politics of the institutions at the center of the simulation. To better consider this possibility, we conduct a survey of students participating in the 2015 Mid-Atlantic European Union Simulation and of appropriate control populations. The survey results indeed suggest that, much more than simply acquiring knowledge about the EU, the simulation experience serves to generate more robust interest in the subject of study

Complementing the sugar code: role of GAGs and sialic acid in complement regulation

Sugar molecules play a vital role on both microbial and mammalian cells, where they are involved in cellular communication, govern microbial virulence, and modulate host immunity and inflammatory responses. The complement cascade, as part of a host’s innate immune system, is a potent weapon against invading bacteria but has to be tightly regulated to prevent inappropriate attack and damage to host tissues. A number of complement regulators, such as factor H and properdin, interact with sugar molecules, such as glycosaminoglycans (GAGs) and sialic acid, on host and pathogen membranes and direct the appropriate complement response by either promoting the binding of complement activators or inhibitors. The binding of these complement regulators to sugar molecules can vary from location to location, due to their different specificities and because distinct structural and functional subpopulations of sugars are found in different human organs, such as the brain, kidney, and eye. This review will cover recent studies that have provided important new insights into the role of GAGs and sialic acid in complement regulation and how sugar recognition may be compromised in disease

Designing a microbial cultivation platform for continuous biopharmaceutical production

The existing biopharmaceutical manufacturing paradigm is poorly suited to produce biologic drugs on demand at a point-of-care. Generally, commercial-scale (~2,000 - 10,000 L) manufacturing using fed-batch cultivation and fixed stainless-steel infrastructure is concentrated in developed nations and results in process cycle times on the order of weeks to months.1,2 Coupled with the complex logistical challenges associated with continuous “plant-to-patient” cold-chains, the geographically biased nature of therapeutic protein production today can limit access to biologic drugs in developing areas of the world.3 There is an opportunity to create technologies capable of rapidly generating biopharmaceuticals in situ in emergency situations, in remote healthcare settings, and in the battlefield. A platform that incorporates a modular suite of bioreactor, purification, and in-line analytics technologies has the potential to bridge this gap if developed in parallel with appropriately engineered stains of a flexible expression host. This poster will describe a multifaceted approach towards the development of a fully automated bench-scale perfusion process for the cultivation of Pichia pastoris and expression of therapeutically relevant heterologous proteins. We demonstrate the application of computational fluid dynamics (CFD) simulations to the optimization of the cultivation environment within our bench-top bioreactors. We further show that Pichia pastoris is amenable to secreting a variety of recombinant proteins spanning a range of preexisting drug classes (e.g. hormones, cytokines, monoclonal antibodies, vaccine antigens). Among these therapeutic proteins are molecules that require proper co-/post-translational processing for bioactivity. We envision that the development of P. pastoris strains with the capability to perform these critical processing steps in vivo will mitigate the need to chemically modify proteins post-expression and reduce the number of unit operations required in a typical upstream process

Surgical approach to limiting skin contracture following protractor myectomy for essential blepharospasm

Purpose: To report our experience with protractor myectomy in patients with benign essential blepharospasm who did not respond to serial botulinum toxin injection, and to describe intra- and postoperative techniques that limited skin contracture while also providing excellent functional and cosmetic results. Methods: The medical records of patients with isolated, benign, essential blepharospasm who underwent protractor myectomy from 2005 to 2008 by a single surgeon were reviewed retrospectively. The technique entailed operating on a single eyelid during each procedure, using a complete en bloc resection of all orbicularis tissue, leaving all eyelid skin intact at the time of surgery, and placing the lid under stretch with Frost suture and applying a pressure dressing for 5-7 days. Results: Data from 28 eyelids in 7 patients were included. Average follow-up was 21.5 months (range, 4-76 months). Of the 28 eyelids, 20 (71.4%) showed postoperative resolution of spasm, with no further need for botulinum toxin injections. In the 8 eyelids requiring further injections, the average time to injection after surgery was 194 days (range, 78-323 days), and the average number of injections was 12 (range, 2-23 injections). All but one eyelid had excellent cosmetic results, without signs of contracture; one eyelid developed postoperative skin contracture following premature removal of the Frost suture and pressure dressing because of concerns over increased intraocular pressure. Conclusions: In our patient cohort, this modified technique resulted in excellent cosmetic and functional results and limited postoperative skin contracture

Exposure to Household Air Pollution from Biomass Cookstoves and Levels of Fractional Exhaled Nitric Oxide (FeNO) among Honduran Women

Household air pollution is estimated to be responsible for nearly three million premature deaths annually. Measuring fractional exhaled nitric oxide (FeNO) may improve the limited understanding of the association of household air pollution and airway inflammation. We evaluated the cross-sectional association of FeNO with exposure to household air pollution (24-h average kitchen and personal fine particulate matter and black carbon; stove type) among 139 women in rural Honduras using traditional stoves or cleaner-burning Justastoves. We additionally evaluated interaction by age. Results were generally consistent with a null association; we did not observe a consistent pattern for interaction by age. Evidence from ambient and household air pollution regarding FeNO is inconsistent, and may be attributable to differing study populations, exposures, and FeNO measurement procedures (e.g., the flow rate used to measure FeNO)