247 research outputs found
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Supporting Complex Business Decisions with a Fuzzy Mobile Assistant
Researchers have recognized the importance of semantic expressiveness in understanding and solving complex problems and have identified a need to incorporate reasoning about uncertainty into decision tools that assist business managers. This study extends current approaches and develops new tools to allow artificial mobile assistants to manage rule-driven consultations by capturing and recommending problem solutions through natural language interfaces. A prototype assistant is described to support fuzzy knowledge representations and fuzzy rule-based consultations. The prototype’s application is implemented in a Windows 8 mobile device and applied in a case study of business outsourcing decisions
Teaching Database Development with Hypertext
This paper discusses our experiences in designing and authoring a hypertext system to guide students through a database project. The system targets instruction in three areas: developing database skills, directing analysis and design of a business\u27s data needs and supporting construction of a database application to meet those business needs. The hypertext tool was built to conform to the standards of Microsoft\u27s WinHelp help system architecture. Initial experiences with the system support the claim that the tool assists students in analyzing, designing and implementing database solutions
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In pursuit of conjugation in one-dimension: Synthetic studies of oligomeric and polymeric organic materials
Chapter 1. Ring-Opening Alkyne Metathesis Polymerization of Dibenzocyclooctynes
A molybdenum(VI) propylidyne substituted with bidentate phenoxides will react with dibenzocyclooctynes in living ring-opening alkyne metathesis polymerization (ROAMP). The corresponding monodentate phenoxides do not yield well-controlled polymerizations. However, if the substrate in the ROAMP reaction is an aliphatic cyclooctyne, uncontrolled, non-living polymerizations take place in all cases.
Chapter 2. Ring-Opening Alkyne Metathesis via a Tungstenatetrahedrane Intermediate
A cyclopropenone-modified dibenzocyclooctyne will undergo a single ring opening alkyne metathesis reaction in the presence of Schrock's tris(tert-butoxy)tungsten(VI) neopentylidyne--a highly active alkyne metathesis catalyst. Despite the enormous amount of ring strain present in and related diphenycyclooctadiynes, these compounds do not readily undergo ring-opening alkyne metathesis polymerization (ROAMP), even with the most active alkyne metathesis catalysts available. The ring-opening of 1 proceeds via a tungstenatetrahedrane intermediate. Because of its sluggish reactivity, we were able to follow the ring-opening reaction by NMR to gain mechanistic insight into this remarkable behavior.
Chapter 3. Functionaliztion of Diphenyloligoenes
Bromine and carboxylic acid substituted α,ω-diphenyl-µ,ν-dicyano-oligoenes (DPDCn) were synthesized up to 9 and 7 olefin units in length, respectively. The carboxylic acid functionalized oligoenes (DPDCn-CO2H) are aligned through hydrogen bonding to DMF in the solid state. These can also be used to direct monolayer formation of Fe3O4 on single crystalline, 100 Gallium Arsenide
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Capturing and Shaping Shifting Requirements using XML and XSLT: A Field Study
This paper explores Extensible Mark-up Language (XML) and Extensible Stylesheet Language Transformations (XSLT) for authoring, presenting and managing system requirements. A field study is presented that explores the influence of XML schema and XSLT rendering and modeling templates on stakeholder communications. The study is of an e-commerce project where an evolving business model and changing partnerships forced the requirements team to continually adapt XML and XSLT tools to capture requirements. Coding procedures categorized resulting repositories of XML documents, XML schema, XSLT templates, stakeholder interviews, field notes, e-mails, and business documents. Qualitative techniques are applied to derive a model summarizing the influence of XML schema, and XSLT rendering and modeling templates. Implications for researchers and practitioners are discussed, including how XML tools support stakeholders by customizing presentations, assisting negotiations and enhancing traceability
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DEAR: A New Technique for Information Extraction and Context-Dependent Text Mining
The desire to store and the need to use electronic data has greatly increased as the power, availability, and connectivity of computers has grown. A large portion of this data is in the form of unstructured text documents. Locating specific information within this amorphous mass of documents is an area of active research. Our contribution to this pursuit is the development of the Document Entity and Resolution (DEAR) system. This system combines semantic similarity matching as provided by the open source WordNet database with the ability to recognize named entities through the OpenCalais system. When used in concert, this provides a novel way for users to quickly find relevant content and detect and identify uniquely named entities within that content. The theory behind the system is defined and the working system is described. This system is then applied to a collection of assessment documents as a proof-of-concept test of its viability. The results are promising and indicate that further research is warranted
Anaerobic Digestion of Cereal Rye Cover Crop
The rapid growth of cover crop planting area in the U.S. helps with erosion control, soil health, control of greenhouse gases, and also provides abundant biomass for the production of bioenergy and bioproducts. Given the cover crops’ compositional heterogeneity and variability, a tolerate platform technology such as anaerobic digestion (AD) is preferred but has not been widely used for cover crop biorefining. This study evaluated the biogas and methane yields from six cereal rye (Secale cereale L.) cover crops grown in the Midwest, using both bench- and pilot-scale anaerobic digesters. The effects of two critical factors, the total solids (TS) content and ensiling, on digester performance were also investigated. Methane yields of 174.79–225.23 L/kg-VS were obtained from the bench-scale tests using cereal rye as the mono feedstock. The pilot-scale test with no pH adjustment showed a slightly higher methane yield. Ensiling increased the methane yield by 23.08% at 6% TS, but disturbed AD at 8% TS, and failed AD at 10% and 15% TS. Findings from this study would help farmers and the biorefining industry to determine the baseline performance and revenue of cereal rye AD and to develop strategies for process control and optimization
CRISPR/Cas9-Induced fad2 and rod1 Mutations Stacked With fae1 Confer High Oleic Acid Seed Oil in Pennycress (Thlaspi arvense L.)
Pennycress (Thlaspi arvense L.) is being domesticated as an oilseed cash cover crop to be grown in the off-season throughout temperate regions of the world. With its diploid genome and ease of directed mutagenesis using molecular approaches, pennycress seed oil composition can be rapidly tailored for a plethora of food, feed, oleochemical and fuel uses. Here, we utilized Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 technology to produce knockout mutations in the FATTY ACID DESATURASE2 (FAD2) and REDUCED OLEATE DESATURATION1 (ROD1) genes to increase oleic acid content. High oleic acid (18:1) oil is valued for its oxidative stability that is superior to the polyunsaturated fatty acids (PUFAs) linoleic (18:2) and linolenic (18:3), and better cold flow properties than the very long chain fatty acid (VLCFA) erucic (22:1). When combined with a FATTY ACID ELONGATION1 (fae1) knockout mutation, fad2 fae1 and rod1 fae1 double mutants produced ∼90% and ∼60% oleic acid in seed oil, respectively, with PUFAs in fad2 fae1 as well as fad2 single mutants reduced to less than 5%. MALDI-MS spatial imaging analyses of phosphatidylcholine (PC) and triacylglycerol (TAG) molecular species in wild-type pennycress embryo sections from mature seeds revealed that erucic acid is highly enriched in cotyledons which serve as storage organs, suggestive of a role in providing energy for the germinating seedling. In contrast, PUFA-containing TAGs are enriched in the embryonic axis, which may be utilized for cellular membrane expansion during seed germination and seedling emergence. Under standard growth chamber conditions, rod1 fae1 plants grew like wild type whereas fad2 single and fad2 fae1 double mutant plants exhibited delayed growth and overall reduced heights and seed yields, suggesting that reducing PUFAs below a threshold in pennycress had negative physiological effects. Taken together, our results suggest that combinatorial knockout of ROD1 and FAE1 may be a viable route to commercially increase oleic acid content in pennycress seed oil whereas mutations in FAD2 will likely require at least partial function to avoid fitness trade-offs
Generating Pennycress (Thlaspi arvense) Seed Triacylglycerols and Acetyl-Triacylglycerols Containing Medium-Chain Fatty Acids
Thlaspi arvense L. (pennycress) is a cold-tolerant Brassicaceae that produces large amounts of seeds rich in triacylglycerols and protein, making it an attractive target for domestication into an offseason oilseed cash cover crop. Pennycress is easily genetically transformed, enabling synthetic biology approaches to tailor oil properties for specific biofuel and industrial applications. To test the feasibility in pennycress of producing TAGs and acetyl-TAGs rich in medium-chain fatty acids (MCFAs; C6–C14) for industrial, biojet fuel and improved biodiesel applications, we generated transgenic lines with seed-specific expression of unique acyltransferase (LPAT and diacylglycerol acyltransferase) genes and thioesterase (FatB) genes isolated from Cuphea viscosissima, Cuphea avigera var. pulcherrima, Cuphea hookeriana, Coco nucifera, and Umbellularia californica. Wild-type pennycress seed TAGs accumulate no fatty acids shorter than 16C and less than 5 mol percent C16 as palmitic acid (16:0). Co-expressing UcFatB and CnLPAT produced up to 17 mol% accumulation of lauric acid (12:0) in seed TAGs, whereas CvFatB1 CvLPAT2 CpDGAT1 combinatorial expression produced up to 27 mol% medium chain FAs Medium Chain Fatty Acids mostly in the form of capric acid (10:0). CpFatB2 ChFatB2 combinatorial expression predominantly produced, in equal parts, up to 28 mol% myristic acid (14:0) and palmitic acid. Genetically crossing the combinatorial constructs into a fatty acid elongation1 (fae1) mutant that produced no 22:1 erucic acid, and with an Euonymus alatus diacylglycerol acetyltransferase (EaDAcT)-expressing line that produced 60 mol% acetyl-TAGs, had no or relatively minor effects on MCFAs accumulation, suggesting fluxes to MCFAs were largely unaltered. Seed germination assays revealed no or minor delays in seed germination for most lines, the exception being CpFatB2 ChFatB2-expressing lines, which had substantially slower seed germination rates. Taken together, these data show that pennycress can be engineered to produce seeds accumulating modest amounts of MCFAs of varying carbon-chain length in TAGs and acetyl-TAGs, with rates of seed germination being delayed in only some cases. We hypothesize that increasing MCFAs further may require functional reductions to endogenous transferases and/or other FA elongases
Molecular tools enabling pennycress (\u3ci\u3eThlaspi arvense\u3c/i\u3e) as a model plant and oilseed cash cover crop
Thlapsi arvense L. (pennycress) is being developed as a profitable oilseed cover crop for the winter fallow period throughout the temperate regions of the world, controlling soil erosion and nutrients run-off on otherwise barren farmland. We demonstrate that pennycress can serve as a user-friendly model system akin to Arabidopsis that is well-suited for both laboratory and field experimentation. We sequenced the diploid genome of the spring-type Spring 32-10 inbred line (1C DNA content of 539 Mb; 2n = 14), identifying variation that may explain phenotypic differences with winter-type pennycress, as well as predominantly a one-to-one correspondence with Arabidopsis genes, which makes translational research straightforward. We developed an Agrobacterium-mediated floral dip transformation method (0.5% transformation efficiency) and introduced CRISPR-Cas9 constructs to produce indel mutations in the putative FATTY ACID ELONGATION1 (FAE1) gene, thereby abolishing erucic acid production and creating an edible seed oil comparable to that of canola. We also stably transformed pennycress with the Euonymus alatus diacylglycerol acetyltransferase (EaDAcT) gene, producing low-viscosity acetyltriacylglycerol- containing seed oil suitable as a diesel-engine drop-in fuel. Adoption of pennycress as a model system will accelerate oilseed-crop translational research and facilitate pennycress’ rapid domestication to meet the growing sustainable food and fuel demands
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