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An Investigation of the Genomic Space and Search for Hydrocarbon Biosynthetic Genes in the Green Microalga Botryococcus braunii
Get PDFThe colonial green microalga Botryococcus braunii is well known for producing liquid hydrocarbons that can be utilized as biofuel feedstocks. B. braunii is taxonomically classified as a single species made up of three chemical races, A, B, and L, that are mainly distinguished by the hydrocarbons produced. These hydrocarbons can be refined into chemically identical petroleum fuel equivalents. Making them a unique organism for the production and/or sourcing of biofuel feedstocks. There has long been a debate over the chemical race classification system used for B. braunii and if these chemical races are a single or different species. Here data is presented from a comparative genomics analysis (Chapter III) from newly assembled draft nuclear genomes of the A and L chemical races (Chapter II). This comparative analysis revealed many differences at the genomic level between all three chemical races, suggesting these chemical races are in fact distinct and different species within the genus Botryococcus. A reclassification is proposed of the three chemical races to the following species names: Botryococcus alkenealis (A race), Botryococcus braunii (B race), and Botryococcus lycopadienor (L race).
Great efforts have been spent trying to elucidate and characterize the biosynthetic pathways responsible for hydrocarbon production in Botryococcus. Previous work has elucidated a nearly full biosynthetic pathway B. braunii (B race). Recently, the first committed step and all pathway intermediates in the hydrocarbon biosynthetic pathway for B. lycopadienor was elucidated. The remaining step in the pathway is the identification and characterization of the proposed reductase(s) that serially reduces these hydrocarbon intermediates to form lycopadiene. Here (Chapter IV), great efforts are detailed in the attempted identification of these reductase(s)
Oyster biology
No full text43 slide Power Point presentation. Created 2004; modified in 2005. Includes sets for oyster biology, dermo watch, WPA bird collection, and World War II bird collectio
Design and Analysis Methods for 3D Printed Concrete Structures
No full textThis dissertation introduced the general design methodology and performance evaluation process of single-story 3D Printed Concrete (3DPC) buildings. The current knowledge gaps in the seismic performance of 3DPC buildings are the general design process and relative Seismic Performance Factors (SPFs). In this research, the FEMA P695 methodology is applied to evaluate their performance and quantify the SPFs.
Two types of Lateral Force Resisting Systems (LFRSs) in 3DPC buildings are proposed and the relative structural information, such as load path, element interaction, and construction suggestions were introduced. The seismic design process for 3DPC buildings with different LFRSs was developed based on design equations from a companion study.
A detailed numerical modeling approach based on shell elements in OpenSees was developed. To perform the Incremental Dynamic Analyses (IDA) efficient, a simplified modeling approach based on truss elements was proposed and the material calibration process was explained. A total number of 48 3DPC shear walls were modeled and the effect of major parameters including aspect ratio, printed layer width, bed-joint reinforcement spacing, and infill pattern in 3DPC shear walls was investigated using the proposed modeling strategy. The comparison indicated that the proposed modeling strategy based on shell elements can capture the lateral strength and failure mechanisms of the 3DPC shear wall with acceptable accuracy.
Building archetype designs for the FEMA P695 process were established on the basis of actual 3DPC buildings and the proposed design process. Numerical models for building archetypes were developed and FEMA P695 methodology was applied. The nonlinear static and dynamic analyses were performed and suggested SPFs were given. 3DPC buildings with Type 1 LFRS showed similar performance to ordinary reinforced masonry and the R factor of 1.5 satisfied the evaluation process with little safety margin. 3DPC buildings with Type 2 LFRS exhibits low ductility and high stiffness whose strength is mainly controlled by minimum wall dimensions
