Extended missions to space have long been a goal of the National Aeronautics and Space Administration (NASA). Accomplishment of NASA's goal requires the development of systems and tools for sustaining human life for periods of several months to several years. This is the primary objective of NASA's Advanced Life Support (ALS) program. This work contributes directly to NASA efforts for ALS, particularly food production. The objective of this work is to develop a systematic methodology for analyzing and improving or modifying ALS technologies to increase their acceptability for implementation in long-duration space missions. By focusing primarily on the food production systems, it is an aim of this work to refine the procedure for developing and analyzing the ALS technologies. As a result of these efforts, researchers will have at their disposal, a powerful tool for establishing protocols for each technology as well as for modifying each technology to meet the standards for practical applications. To automate the developed methodology and associated calculations, a computer-aided tool has been developed. The following systematic procedures are interrelated and automatically integrated into the computer-aided tool: • Process configuration, with particular emphasis given to food production (e.g., syrup and flour from sweet potato, starch from sweet potato, breakfast cereal from sweet potato); • Modeling and analysis for mass and energy tracking and budgeting; • Mass and energy integration • Metrics evaluation (e.g., Equivalent System Mass (ESM)). Modeling and analysis is achieved by developing material- and energy-budgeting models. Various forms of mass and energy are tracked through fundamental as well as semiempirical models. Various system alternatives are synthesized and screened using ESM and other metrics. The results of mass, energy and ESM analyses collectively revealed the major consumers of time, equivalent mass, and energy, namely evaporation, condensation, dehydration, drying and extrusion. The targeted processes were subsequently targeted for modifications. In conclusion, this work provides a systematic methodology for transforming non-conventional problems into traditional engineering design problems, a significant contribution to ALS studies.

Sweet sorghum (Sorghum bicolor) has potential as a bioenergy feedstock due to its high yield potential and the production of simple sugars for fermentation. Sweet sorghum cultivars are typically tall, high biomass types with juicy stalks and high sugar concentration. These sorghums can be harvested, milled, and fermented to ethanol using technology similar to that used to process sugarcane. Sweet sorghum has advantages in that it can be planted by seed with traditional planters, is an annual plant that quickly produces a crop and fits well in crop rotations, and it is a very water-use efficient crop. Processing sweet sorghum is capital intensive, but it could fit into areas where sugarcane is already produced. Sweet sorghum could be timed to harvest and supply the sugar mill during the off season when sugarcane is not being processed, be fit into crop rotations, or used in water limiting environments. In these ways, sweet sorghum could be used to produce ethanol in the Southern U.S and other tropical and subtropical environments. Traditionally, sweet sorghum has been grown as a pureline cultivar. However, these cultivars produce low quantities of seed and are often too tall for efficient mechanical harvest. Sweet sorghum hybrids that use grain-type seed parents with high sugar concentrations are one way to overcome limitation to seed supply and to capture the benefits of heterosis. There are four objectives of this research. First to evaluate the importance of genotype, environment, and genotype-by-environment interaction effects on the sweet sorghum yield and composition. The second objective is to determine the presence and magnitude of heterosis effects for traits related to sugar production in sweet sorghum. Next: to study the ability of sweet sorghum hybrids and cultivars to produce a ratoon crop and determine the contribution of ratoon crops to total sugar yield. The final objective is to evaluate variation in composition of sweet sorghum juice and biomass. Sweet sorghum hybrids, grain-type sweet seed parents, and traditional cultivars that served as male parents were evaluated in multi-environment trials in Weslaco, College Station, and Halfway, Texas in 2007 and 2008. Both genotype and environment influenced performance, but environment had a greater effect than genotype on the composition of sweet sorghum juice and biomass yield. In comparing performance, elite hybrids produced fresh biomass and sugar yields similar to the traditional cultivars while overcoming the seed production limitations. High parent heterosis was expressed among the experimental hybrids for biomass yield, sugar yield and sugar concentration. Additional selection for combining ability would further enhance yields and heterosis in the same hybrid. Little variation was observed among hybrids for juice and biomass composition suggesting that breeding efforts should focus on yield before altering plant composition.

Sweet sorghum is a highly versatile C4 grass noted for its improved drought tolerance and water use efficiency relative to sugarcane. Sweet sorghum is well suited for ethanol production due to a rapid growth rate, high biomass production, and a wide range of adaptation. Unlike the 12-18 month growth cycle of sugarcane, sweet sorghum produces a harvestable crop in three to five months. Sweet sorghum and sugarcane crops are complementary and in combination can extend the sugar mill seasons in many regions of the world to an estimated 8 months. Seasonal growth and weather patterns both optimize and restrict production of each crop to specific times of the year, however these are different for the two crops. In addition to temporally spacing the date of harvest between crops, the genetic variability of maturity within the crops may also be used to extend the mill seasons; specific hybrids can be used and selected to maximize yield throughout the harvest season. Under favorable growing environments, sweet sorghum hybrids of all maturity groups produced sugar yields ranging from 2.8 to 4.9 MT/ha. Early/medium, late, and very late maturity hybrids planted during April, May, and June planting dates are necessary to maximize the mill season. In this study, early/medium maturity hybrids planted during April and May matured for harvest between late July and mid-August. June planting dates were unfavorable for early/medium maturity hybrids. In addition, late and very late maturity hybrids planted during April matured for harvest in late August; the additional growing season thus resulted in higher sugar yields. Timely planting of late and very late maturity hybrids in April, May, and June produce the maximum yields for harvests after mid August. Intermittent use of late and very late maturity hybrids can therefore extend sugar milling seasons into mid November if so desired.

CSI at UBC: How David Sweet is using dental forensics to pit modern science against criminals.

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The enrichment of B-carotene, a precursor to vitamin A, in the local sweetpotato (Ipomoea batatas L.) cultivars is an attractive option in order to improve vitamin A intake in Zambia. The study was conducted to: 1) identify sweetpotato genotypes high in B-carotene content and high root dry mass (RDM) and to determine their combining ability, as measured through their progeny performance; and 2) screen progeny for root characteristics, yield, B-carotene content, and RDM. Firstly, a participatory rural appraisal (PRA) was conducted to determine the consumer preferences for sweetpotato. These preferences would form the basis for selecting desirable genotypes. Secondly, five selected parents were crossed in a full diallel for genetic variance studies. A selected subset of the diallel progeny were evaluated in three environments. Thirdly, 15 polycross progeny were evaluated for stability in five environments using additive main effect and multiplicative interaction (AMMI). The PRA revealed that consumers preferred high RDM combined with high fresh root yield. The diallel crosses recorded significant general combining ability (GCA) and specific combining ability (SCA) effects for B-carotene, RDM, harvest index (HI) and root fresh yield (RFY). The ratios of GCA to SCA variances were large (0.68-0.92). Two high B-carotene parents exhibited positive high GCA effects, indicating that additive gene effects were predominant in the inheritance of B-carotene. Reciprocal mean squares were not significant for RDM but they were significant (p=0.01) for B-carotene content. The estimate of narrow sense heritability of RDM (76.3%) was high; but heritability of B-carotene (20.9%), HI (29.1%) and RFY (34.9%) were much lower. These results suggest that rapid genetic gains should be possible with mass selection breeding techniques based on the phenotype of the parent for RDM but progress will be slow for B-carotene content HI, and RFY. The AMMI analysis identified progeny G2 (B-carotene content = 5.0 mg 100 g-1 and RDM = 37%), G6 (B-carotene content = 4.7 mg 100 g-1 and RDM = 37%), and G8 (B-carotene content = 4.7 mg 100 g-1, RDM = 35%) from the polycross as stable across environments for both B-carotene content and RDM. Genotype G3 was best suited to one of the test environments and had the highest B-carotene content (9.421 mg 100 g-1) and a high RDM (35.47%). / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.

Coleomegilla maculata is a beneficial coccinellid commonly found in sweet cornfields in Kentucky. Previous work on C. maculata has shown an ovipositional preferencefor the weed Acalypha ostryaefolia, compared to three selected weed species and corn. Also, predation of C. maculata egg clusters on A. ostryaefolia was less compared toclusters on corn and the presence of A. ostryaefolia led to higher densities of C. maculata larvae on corn. I determined C. maculata ovipositional preference among weed species in fieldtests using nine common weeds. I also examined ovipositional preference using just A.ostryaefolia and Abutilon theophrasti. I assessed the roles of potential prey densities,plant structures, and weed attractiveness to adult C. maculata. Finally, I examineddiurnal and nocturnal predation of C. maculata eggs on corn, A. ostryaefolia, A.theophrasti, and Amaranthus hybridus. Significant ovipositional preference was always observed for A. theophrasti. C. maculata egg clusters on A. theophrasti and A.ostryaefolia were preyed upon less frequently than clusters on A. hybridus and corn.

Sweet Corn Inhibitor (SCI), a small (11811Da.) protein from the seeds of opaque-2 corn is a potent and specific inhibitor of trypsin and the activated Hageman Factor (Factor βXIIa) of the human blood plasma coagulation system. With the eventual aim of obtaining insight into the structure- function relationships of the selective SCI-pXIIa interaction, a synthetic gene for SCI was cloned into Saccharomyces cerevisiae (yeast) and Escherichia coli (E.coli) expression systems in an attempt to obtain overexpression of the recombinant gene product. The establishment of functional expression, together with an isolation and purification procedure for SCI would provide a system for obtaining selected reactive-site mutants of SCI by cassette- and oligonucleotide-directed mutagenesis. A yeast secretion vector for a truncated form of SCI (tSCI) was constructed by cloning the gene for α-factor prepro-tSCI fusion, downstream to the α-mating factor (MFα1) promoter of yeast. Yeast transformants containing the expression vector failed to express and secrete the desired product. The synthetic gene encoding the complete SCI sequence was cloned into E.coli expression vectors that directed both cytoplasmic and periplasmic expression. In cytoplasmic expression, the SCI gene was cloned directly downstream to the powerful, inducible λ-phage PL- and trc-promoters. No expression was obtained with the latter. With the former, expression levels of up to 3% of the total bacterial protein were obtained. These levels were improved 3- to 4-fold on incorporation of the E.coli dnaY gene product. Solubilisation and refolding of the purified SCI inclusion bodies failed to yield the active, correctly folded product. Failure to obtain an N-terminal sequence indicated an incompletely processed N-terminal methionine. For periplasmic expression, SCI, fused in-frame to the signal sequence of OmpA, a major E.coli outer membrane protein, was cloned into the same λ-phage P_L promoter vector. High levels (=10%) of expression of insoluble SCI were obtained. The nearly homogeneous product was obtained by a two-step procedure, involving ion-exchange chromatography, followed by hydrophobic interaction chromatography. Characterisation by N-terminal sequencing, SDS-PAGE and electrospray mass spectrometry, confirmed the presence of correctly processed SCI in the form of covalently associated dimers. Refolding studies are at present in progress.

Internal fruit rot, caused by Fusarium lactis, is as an important disease of greenhouse sweet pepper. Fungal growth was studied microscopically during anthesis and fruit development. Hyphae were observed on the stigmatal surface one day after inoculation (DAI), and in the transmitting tissues of the style and inside the ovary at 5 and 6 DAI. Symptomless seeds from infected fruits yielded colonies of F. lactis when cultured axenically, and typical disease symptoms were observed when fruits were dissected at 45 DAI. Isolates of F. lactis and the related species F. proliferatum and F. verticillioides, which are also associated with internal fruit rot, produced the mycotoxins beauvericin, moniliformin and fumonisin B1 in various combinations, both in infected fruits and in vitro. These findings suggest that internal fruit rot is initiated through infection of the stigma and style during anthesis, and that mycotoxin contamination of infected fruit could pose a health concern. / Plant Science