The hematopoietic stem cell (HSC) niche is the site where HSCs reside in vivo. The HSC niche is formed by supporting cells that provide structure and appropriate environmental cues for HSCs. In this study, three components of the HSC niche were evaluated for their influence on HSC expansion ex vivo:...
Granular matter and living cells represent two extremes of what have come to be regarded as complex systems - systems characterized by a richness in global behavior that is not easily deduced from the interactions of their individual parts, even when those interactions are simple and well understood. On the...
The prediction of multicomponent adsorption equilibria from pure component data alone has been an active research area for over forty years. The Ideal Adsorbed Solution theory (IAS) has been the standard method of doing so, but contains an embedded assumption of Langmuir mixing. This assumption causes its predictions to be...
The recent tightening of permissible NOx release from diesel-powered engines has intensified the search for a catalytic system that can effectively remove NOx under challenging diesel exhaust conditions. Hydrogen-assisted selective catalytic reduction (H2-SCR) using supported palladium catalysts offers significant promise for lean NOx treatment due to its high activity at...
The task of designing porous materials for use in specific applications requires a detailed understanding of the adsorption process and how adsorption is affected by material properties. Applications of interest include maximizing gravimetric or volumetric adsorption capacity for hydrogen and carbon dioxide and increasing the selectivity for carbon dioxide in...
Two subjects are the focus of this dissertation: Au/TiO2 catalyst used for oxidation of CO at low temperature and siloxane nanocages, a novel material (~2nm) recently developed in our group
While bulk gold is chemically inert, gold supported as nanoparticles is remarkably active for the oxidation of carbon monoxide at...
Using a novel DNA-microarray hybridization protocol, the diffusion distance during static microarray hybridization was estimated for Cy3- and Cy5-labeled cDNA probes as 3.8 and 2.6 mm, respectively, despite having almost identical molecular masses. Continuous mixing during microarray hybridization resulted in a 15-20% increase in signal intensity over arrays hybridized statically....
The physics of granular materials is one of the big questions in science. Granular materials serve as a prototype of collective systems far from equilibrium and fundamental questions remain. At the same time, an understanding of granular materials has tremendous practical importance. Among practical problems, granular mixing and its interplay...
Megakaryocytic cells (Mks) are derived from hematopoietic stem cells (HSCs) and give rise to platelets. Ex vivo culture of HSCs under conditions that promote Mk differentiation has been proposed as a method for producing Mks and platelets for cell therapies. Mk maturation involves the development of polyploid cells via endomitosis,...
Little is known about the transcriptional events underlying megakaryocytic (Mk) differentiation from hematopoietic stem cells. We sought to identify genes and pathways not previously associated with megakaryopoiesis and to evaluate the CHRF-288-11 (CHRF) megakaryoblastic cell line as a model system for investigating megakaryopoiesis.
Using DNA microarrays, Q-RT-PCR, and protein-level assays,...