Brown, Ashland Oral History Interview

Dean of School of Engineering & Professor of Mechanical Engineering (1991-2016). Topics include: Changes and growth in scope of the academic programs, advancements in student scholarship (use of finite element analysis), challenges that the university could help the Stockton Community improve in (K-12), and challenges that the University could achieve in the future (advancement, research, Stockton K-12).https://scholarlycommons.pacific.edu/esohc/1131/thumbnail.jp

A comparison of analytic approaches for individual patient data meta-analyses with binary outcomes

Abstract Background Individual patient data meta-analyses (IPD-MA) are often performed using a one-stage approach-- a form of generalized linear mixed model (GLMM) for binary outcomes. We compare (i) one-stage to two-stage approaches (ii) the performance of two estimation procedures (Penalized Quasi-likelihood-PQL and Adaptive Gaussian Hermite Quadrature-AGHQ) for GLMMs with binary outcomes within the one-stage approach and (iii) using stratified study-effect or random study-effects. Methods We compare the different approaches via a simulation study, in terms of bias, mean-squared error (MSE), coverage and numerical convergence, of the pooled treatment effect (β 1) and between-study heterogeneity of the treatment effect (τ 1 2 ). We varied the prevalence of the outcome, sample size, number of studies and variances and correlation of the random effects. Results The two-stage and one-stage methods produced approximately unbiased β 1 estimates. PQL performed better than AGHQ for estimating τ 1 2 with respect to MSE, but performed comparably with AGHQ in estimating the bias of β 1 and of τ 1 2 . The random study-effects model outperformed the stratified study-effects model in small size MA. Conclusion The one-stage approach is recommended over the two-stage method for small size MA. There was no meaningful difference between the PQL and AGHQ procedures. Though the random-intercept and stratified-intercept approaches can suffer from their underlining assumptions, fitting GLMM with a random-intercept are less prone to misfit and has good convergence rate

Hybrid Vector and Method Resulting in Protein Overproduction by Eukaryotic Cells

A hybrid vector carrying a first and second DNA segments operationally linked thereto, the first DNA segment encoding a protein capable of cross-linking to the cap structure of mRNA and mediating ribosome-binding, and the second DNA segment encoding a polypeptide or protein, the vector being capable of replication, transcription and translation to express the factor and the polypeptide or protein upon transformation of a eukaryotic host, and the polypeptide or protein being expressed at a level higher than the level of expression thereof in the absence of the first DNA segment. A eukaryotic host is transformed with this hybrid vector. Also disclosed is a method of increasing the synthesis of a polypeptide or protein in a eukaryotic host cell

Mitigation of Explosive Blast Effects on Vehicle Floorboard

This thesis investigates methods for mitigating the blast effects on the floorboard of passenger vehicles due to the detonation of explosives buried in water saturated sand underneath vehicles. The effects on floorboard acceleration of adding a vehicle hull, several types of floorboard bracing, the use of foam to fill the gap between the floorboard and hull, and the use of foam to isolate the floorboard from the hull. In addition, several tests have been conducted to examine how the distance of the floorboard from the ground affects the acceleration of the floorboard after the detonation. Testing showed that the addition of a hull to a vehicle, the hulls geometry, bracing of the floorboard, and increasing ground clearance all are able to help reduce floorboard accelerations. However, floorboard bracing had the potential to make accelerations much higher it is hit by the hull during testing. Foam filling between the hull and floorboard as well as a foam frame to isolate the floorboard from the hull did not have positive results. The primary method of investigation is differentiating a velocity profile found with the use of bar magnet velocity gages on the small scale model floorboard. Several other possible methods of investigation are discussed

Toward a Coordinated Global Observing System for Seagrasses and Marine Macroalgae

In coastal waters around the world, the dominant primary producers are benthic macrophytes, including seagrasses and macroalgae, that provide habitat structure and food for diverse and abundant biological communities and drive ecosystem processes. Seagrass meadows and macroalgal forests play key roles for coastal societies, contributing to fishery yields, storm protection, biogeochemical cycling and storage, and important cultural values. These socio-economically valuable services are threatened worldwide by human activities, with substantial areas of seagrass and macroalgal forests lost over the last half-century. Tracking the status and trends in marine macrophyte cover and quality is an emerging priority for ocean and coastal management, but doing so has been challenged by limited coordination across the numerous efforts to monitor macrophytes, which vary widely in goals, methodologies, scales, capacity, governance approaches, and data availability. Here, we present a consensus assessment and recommendations on the current state of and opportunities for advancing global marine macrophyte observations, integrating contributions from a community of researchers with broad geographic and disciplinary expertise. With the increasing scale of human impacts, the time is ripe to harmonize marine macrophyte observations by building on existing networks and identifying a core set of common metrics and approaches in sampling design, field measurements, governance, capacity building, and data management. We recommend a tiered observation system, with improvement of remote sensing and remote underwater imaging to expand capacity to capture broad-scale extent at intervals of several years, coordinated with stratified in situ sampling annually to characterize the key variables of cover and taxonomic or functional group composition, and to provide ground-truth. A robust networked system of macrophyte observations will be facilitated by establishing best practices, including standard protocols, documentation, and sharing of resources at all stages of workflow, and secure archiving of open-access data. Because such a network is necessarily distributed, sustaining it depends on close engagement of local stakeholders and focusing on building and long-term maintenance of local capacity, particularly in the developing world. Realizing these recommendations will produce more effective, efficient, and responsive observing, a more accurate global picture of change in vegetated coastal systems, and stronger international capacity for sustaining observations

Stationarity and Geometric Ergodicity of BEKK Multivariate GARCH Models

Conditions for the existence of strictly stationary multivariate GARCH processes in the so-called BEKK parametrisation, which is the most general form of multivariate GARCH processes typically used in applications, and for their geometric ergodicity are obtained. The conditions are that the driving noise is absolutely continuous with respect to the Lebesgue measure and zero is in the interior of its support and that a certain matrix built from the GARCH coefficients has spectral radius smaller than one. To establish the results semi-polynomial Markov chains are defined and analysed using algebraic geometry.Comment: version to appear in Stochastic Processes and their Applications, 2011; http://www.sciencedirect.com/science/article/pii/S030441491100137

Effects of physiological self-crowding of DNA on shape and biological properties of DNA molecules with various levels of supercoiling

DNA in bacterial chromosomes and bacterial plasmids is supercoiled. DNA supercoiling is essential for DNA replication and gene regulation. However, the density of supercoiling in vivo is circa twice smaller than in deproteinized DNA molecules isolated from bacteria. What are then the specific advantages of reduced supercoiling density that is maintained in vivo? Using Brownian dynamics simulations and atomic force microscopy we show here that thanks to physiological DNA-DNA crowding DNA molecules with reduced supercoiling density are still sufficiently supercoiled to stimulate interaction between cis-regulatory elements. On the other hand, weak supercoiling permits DNA molecules to modulate their overall shape in response to physiological changes in DNA crowding. This plasticity of DNA shapes may have regulatory role and be important for the postreplicative spontaneous segregation of bacterial chromosome