Computing Homology of Hypergraphs

In the modern age of data science, the necessity for efficient and insightful analytical tools that enable us to interpret large data structures inherently presents itself. With the increasing utility of metrics offered by the mathematics of hypergraph theory and algebraic topology, we are able to explore multi-way relational datasets and actively develop such tools. Throughout this research endeavor, one of the primary goals has been to contribute to the development of computational algorithms pertaining to the homology of hypergraphs. More specifically, coding in python to compute the homology groups of a given hypergraph, as well as their Betti numbers have both been top priorities

X-Ray Spectroscopy of NiO and Nanodiamond at SSRL

The first aspect of this research project focuses on investigating the surface chemistry of high pressure high temperature (HPHT) nanodiamond by using X-ray spectroscopy techniques at the Stanford Synchrotron Radiation Lightsource (SSRL). HPHT nanodiamond is being examined as a biosensing tool for electric field detection based on the fluorescent nitrogen vacancy center hosted within diamond. With use of the transition edge spectrometer (TES), a state-of-the-art X-ray fluorescence detector, we are able to probe the surface and bulk properties of diamond. Preliminary work using density functional theory (DFT) has been done, offering insight into ground state energies and electronic structure. DFT will be used to perform future calculations. The second aspect of this research project investigates effects like saturation which distorts the true X-ray fluorescence-yield absorption spectrum, as well as various probing geometries with attention directed towards dilute samples of nickel oxide mixed with graphite. A typical method used to analyze the electronic structure of materials is electron yield detection. However, due to limitations in the escape depth of the electrons in such a method, the overall electron yield spectra is unrepresentative of bulk properties. Thus, we shift techniques to that of florescence yield detection. These two research endeavors serve to improve XAS techniques and advance nanodiamond for medical applications

Foxtail barley (Hordeum jubatum) control with propoxycarbazone-sodium and fluazifop-p-butyl in three Alaska Native grass species

Thesis (M.S.) University of Alaska Fairbanks, 2007Foxtail barley is one of the most detrimental weeds for the Alaska native grass seed industry. Its control is essential for improving seed production and stand longevity so producers can meet statewide seed demands. The objective of this study was to determine suitable chemical controls of foxtail barley for three different native grass species: 'Nortran' tufted hairgrass (Deschampsia caespitosa L.), 'Gruening' alpine bluegrass (Poa alpina L.), and 'Wainwright' slender wheatgrass (Elymus trachycalus L.) formerly (Agropyron pauciflorum L.). Field and greenhouse experiments were performed to identify selectivity between two herbicide compounds and the crops studied. Foxtail barley was extremely sensitive to both compounds at the 1X rate whereas 'Nortran' tufted hairgrass was tolerant of propoxycarbazone. 'Gruening' alpine bluegrass and 'Wainwright' slender wheatgrass were not tolerant of either compound at the full rate but showed greater tolerance of propoxycarbazone at the 1/2X rate. Propoxycarbazone is a potential tool for foxtail barley control in all three native grass species used for seed production in Alaska

Afinidades afectivas: La política del exceso en el melodrama coreano

Jackson, E. (2007). Afinidades afectivas: La política del exceso en el melodrama coreano. Nosferatu. Revista de cine. (55):49-58. http://hdl.handle.net/10251/41512.Importación Masiva49585

Power Density Spectra and Their Applicatioion in the Determination of Aircraft Gust Loads

Civil Engineerin

Salt Lake County Agriculture Profile

This publication includes a report that gives agricultural facts and statistics pertaining to Salt Lake County

Henderson-Ouachita Faculty Woodwind Quintet

This is the program for the Henderson-Ouachita Faculty Woodwind Quintet concert held on March 27, 1973, in Mitchell Hall Auditorium. The Henderson faculty included David Etienne on flute, Wanda Jackson on oboe, and Earl Hesse on clarinet. The Ouachita faculty included Gregory Umber on horn and Charles Wesley on bassoon

Propionate metabolism and its relationship to leghemoglobin biosynthesis in soybean nodules

Experiments are reported which demonstrate that a cobalt deficiency in R. meliloti results in a decreased cytochrome content of bacterial cells. It is concluded that the effect of cobalt deficiency on cytochrome content of Rhizobium cells and on the leghemoglobin content of nodules possibly may be explained by an effect of cobalt deficiency on the utilization of propionate. Radiotracer experiments have provided evidence that propionate may be utilized for heme synthesis as well as for the maintenance of the citric acid cycle in nodules. When soybean nodules are incubated with propionate-2-C¹⁴, the intermediates of the citric acid cycle not only become labeled with C¹⁴ but also the heme moiety of leghemoglobin becomes labeled. The incorporation of propionate-2-C¹⁴ into heme is linear with time and it appears that propionate is utilized without a lag period. The rate of incorporation of propionate-2-C¹⁴ into heme is more rapid than the rate of incorporation of succinate-2-C¹⁴ and citrate-1, 5-C¹⁴, however, these rates of incorporation may be influenced by different endogenous pool sizes of organic acids. It can be concluded from additional radioactive tracer experiments that the supply of succinyl-CoA from propionate is competitive with the supply of succinyl-CoA from the citric acid cycle. It was observed that when the concentration of propionate was high in the incubation mixture, the rate of succinate-2-C¹⁴ incorporation into heme was inhibited. Furthermore, when a large amount of substrate (succinate or acetate) which can be utilized by the citric acid cycle enzymes is added to the incubation mixture using whole nodules, the rate of incorporation of propionate-2-C¹⁴ into heme is reduced. The addition of acetate to the incubation mixture reduced the rate of incorporation of propionate-2-C¹⁴ into heme by 33 percent, yet it stimulated the citric acid cycle activity and increased the rate of incorporation of succinate-2-C¹⁴ into heme by nearly 50 percent. Since C¹⁴-labeled metabolites were incorporated into the heme moiety of leghemoglobin, a method was developed for the isolation of pure heme from nodules. In brief, the heme was extracted with acid acetone and reextracted with chloroform. After separation and evaporation of the chloroform, the pyridine hemochromogen was isolated by column chromatography from a silicone impregnated cellulose column. The fact that propionate is readily utilized by bacteroids suggested that this compound may be a normal metabolite in nodules. No detectable pool size of propionate was found however, in either soybean nodules or in isolated bacteroids. These results indicated that propionate may be utilized as rapidly as it is formed. An investigation was initiated therefore to determine whether or not lactate could be a precursor of propionate in this symbiotic relationship. Tracer experiments have indicated that lactate-1-C¹⁴ and lactate-2-C¹⁴ are incorporated into the heme moiety of leghemoglobin at approximately equal rates. The rate of incorporation of lactate-C¹⁴ into heme is significantly decreased by the addition of non-radioactive propionate to the reaction mixture, and isolated propionate from this mixture shows that propionate becomes radioactive. Further experiments using a cell-free extract from nodule bacteroids demonstrated the direct conversion of lactate to propionate. The cofactor requirements for this enzymatic conversion are ATP, Mg⁺⁺, NADH and coenzyme A. The rate of C¹⁴ accumulation in propionate from lactate-1-C¹⁴ is inhibited by the addition of nonradioactive a.crylate, suggesting but not proving that acrylate may be an intermediate in the reaction

Probing the Surface of Nanodiamonds at Stanford Synchrotron Radiation Lightsource and San Jose State University

The nitrogen-vacancy center in diamond is a promising tool in oncology, electric field sensing, and quantum cryptography. High-pressure high-temperature (HPHT) nanodiamonds (NDs) are prime contenders for these fields because they host nitrogen-vacancy centers (NVCs) which are applicable towards cancer detection and electric and magnetic field sensing. However, to apply HPHT NDs to these fields, the surface must first be functionalized—a difficult process because of the inert nature of the surface. The project at hand focuses on surface modification of HPHT NDs with amines to allow for further bioconjugation of small molecules and plasmonic shells. This is done via liquid-phase chemistry and high-temperature gas-phase chemistry. To characterize the surface of aminated NDs, samples are probed using synchrotron radiation at the Stanford Synchrotron Radiation Lightsource (SSRL) alongside the transmission edge spectroscopy (TES) detector. Aminated NDs were characterized using X-ray photoelectric spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) at SSRL. X-ray spectra are suggestive of multiple nitrogen moieties on the surface of the aminated NDs. With verification of a homogeneously amine-terminated surface, the NDs are prepared for further functionalization which can be targeted to enhance the properties of the NVC charge states for applications in enhanced electric field and voltage sensing