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  • Thesis

  • Authors: Ramsey, Philip Wharton (2006)

  • Chapter 2: Polyphasic studies that used phospholipid fatty acid analysis (PLFA) in conjunction with community level physiological profiling (CLPP) or PCR-based molecular methods were analyzed in order to evaluate the power of each strategy to detect treatment effects on soil microbial community structure (MCS). We found no studies where CLPP or PCR-based methods differentiated treatments that were not also differentiated by PLFA. In 14 of 32 studies (44%), PLFA differentiated treatments that were not resolved by CLPP analysis. In 5 of 25 studies (20%), PLFA differentiated treatments that were not resolved by PCR-based methods. We discuss PLFA, CLPP, and PCR-based methods with respect to power to discriminate change in MCS versus potential for characterization of underlying populat...

  • Thesis

  • Authors: Li, Lin (2006)

  • Small GLUT4-containing vesicles represent the major insulin-responsive compartment in fat and skeletal muscle cells. These vesicles derive from the perinuclear "donor" compartment that represents recycling endosomes and/or trans-Golgi reticulum. However, the molecular mechanism of the formation of these vesicles is not yet known. In order to address the problem of GLUT4 targeting to the perinuclear "donor" compartment, we created several "gain of function" chimeric molecules between GLUT4 and cellugyrin, a four transmembrane protein that shares a part of the intracellular trafficking route with GLUT4, but is excluded from insulin-responsive vesicles. Cellugyrin with the carboxy-terminal tail substituted by that of GLUT4 was localized in the perinuclear "donor" compartment, but its ...

  • Thesis

  • Authors: Sayers-Fay, Andrew Lawrence (2006)

  • This study examines the relative significance of natural organic matter (NOM) quality and mineral surfaces for the sorption of chlorpyrifos (phosphorothioic acid, 0,0-diethyl O-[3,5,6-trichloro-2-pyridinyl] ester) and diazinon (phosphorothioic acid, 0,0-diethyl 0-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester) on eight California soils, sediments, and suspended estuary sediment. Their aggregate behavior reveals some sorption behaviors of semi-polar contaminant with environmental sorbents. NOM was characterized with pyrolysis-gas chromatography-mass spectrometry (py-GC¬MS) into biological source and chemical class groupings. X-ray diffraction was used to quantitate the minerals present and N2-BET isotherms were used to determine mesopore structure. NOM was removed with hypochlor...

  • Thesis

  • Authors: Miao, Mingming (2006)

  • In addition to transporting oxygen and carbon dioxide, red blood cells (RBCs) actually regulate blood flow in the smallest arteries. The RBCs accomplish this by releasing adenosine triphosphate (ATP) in areas of reduced blood flow. RBCs can detect reduced oxygen concentration, reduced pH, and, as well, the shear stress of deformation. Reduced oxygen concentration, reduced pH and physical deformation are the "signals" which cause red cells to elicit local production of nitric oxide, which can increase regional blood flow. Thus, in addition to carrying out complex transport functions, the RBCs play a critical role in the regulation of blood flow. Forcing RBCs through filters is the method most commonly used to study deformation-induced ATP release. The shear stress imposed on RBCs by...

  • Thesis

  • Authors: Xu, Ruifeng (2006)

  • Collocation is a lexical phenomenon in which two or more words are habitually combined together as some conventional way of saying things. Collocation information is essential to many natural language processing tasks such as word sense disambiguation, machine translation, and information extraction. Most of current works on collocation extraction are statistical based with limited precision and recall because they can not well distinguish word co-occurrences, which are statistically 'significant, from true collocations, which are of habitual use and are thus either syntactically or semantically significant. The objective of this study is to investigate methods to improve the performance of Chinese collocation extraction algorithms. Different types of collocations are identified. C...

  • Thesis

  • Authors: Feliciano, Joe L. (2006)

  • The main objective of this dissertation is to explore both the technological and organizational aspects of the success criteria of Knowledge Management Systems (KMS), and focus on the process of building an organizational knowledge base for operational knowledge reuse. In a time of change, more organizations are deploying a variety of Knowledge Management Systems to enhance business processes and performance. Information and communication technology (ICT) has provided abundant tools and utilities to enable such systems. After nearly a decade of practice in knowledge management, the results are mixed at best and the type of systems utilized are very diverse and often fragmented in infrastructure. In identifying these enabling criteria in a knowledge management system, the author w...

  • Thesis

  • Authors: McDonnell, Ryan (2006)

  • A number of organometallic complexes utilize carbamate ligands to incorporate CO2 into new molecules. In order to better understand metal-carbamate chemistry, a series of CO2 reactive alkylaminozinc complexes were synthesized by the addition of dimethylzinc to secondary amines, resulting in the isolation of Zn(CH3)2(HNC4H8O)2, 1. The addition of one equivalent of CO2 to 1 resulted in the formation of the partially converted complex [Zn(CH3,)(HNC4H8O)(02CNC4H8O)]n, 2. Addition of CO2 in excess under anhydrous conditions formed the complex [Zn(02CNC4H8O)2]n, 3, and the addition of one quarter equivalent of H2O to 3 caused the formation of the Zn4(O2CNC4H8O)6 complex, 4. The kinetics of CO2 addition to 1 indicated the presence of a pentacoordinate zinc transition state that is responsi...

  • Thesis

  • Authors: Graham, Thomas H. (2006)

  • The first section describes the synthesis of the Cl, to C11' side chain of leucascandrolide A. The key step of the synthesis is a modified Robinson-Gabriel synthesis of the oxazole. The Cl, to C11, side chain was constructed in 9 steps and 7% overall yield. The second section describes the synthesis of 2-alkynyl oxazoles and subsequent transformations into a variety of useful motifs. The conjugate addition of nucleophiles to 2-alkynyl oxazoles under basic conditions affords vinyl ethers, vinyl thioethers and enamines. The addition of ethanedithiol affords dithiolanes that can be transformed into ethyl thioesters and ketones. Nucleophilic additions of thiols to 2-alkynyl oxazolines affords oxazoline thioethers. Additions of halides under acidic conditions stereoselectively affords v...

  • Thesis

  • Authors: Adair, Brian Andrew (2006)

  • Crystalline nanoporous materials like zeolites and metal phosphates (e.g. AlPOs) are used commercially for catalysis, adsorption, molecular sieving, and ion exchange. Their properties are related to both their porous architectures and chemical compositions. Materials that incorporate tin(II) and antimony(III), with stereochemically active lone electron pairs, could impart properties different from those of materials based on aluminum, cobalt, zinc, iron, and other metals that adopt [MO4] tetrahedra. Exploratory hydrothermal synthesis resulted in thirty new tin(II) and antimony(III) materials, including the first open-framework antimony(III) phosphate. Structure determination was by single crystal X-ray diffraction. Some materials incorporate a three-ring chain motif observed in othe...

  • Thesis

  • Authors: Cecil, Matthew Steven (2006)

  • The heat kernel measure vt is constructed on W(G), the group of paths based at the identity on a simply connected complex Lie group G. An isometric map, the Taylor map, is established from the space of L2(vt)-holomorphic functions on W(G) to a subspace of the dual of the universal enveloping algebra of Lie(H(G)), where H(G) is the Lie subgroup of finite energy paths. Surjectivity of this Taylor map can be shown in the case where G is stratified nilpotent.