Hierarchical Analysis of the Omega Ontology

Initial delivery for mathematical analysis of the Omega Ontology. We provide an analysis of the hierarchical structure of a version of the Omega Ontology currently in use within the US Government. After providing an initial statistical analysis of the distribution of all link types in the ontology, we then provide a detailed order theoretical analysis of each of the four main hierarchical links present. This order theoretical analysis includes the distribution of components and their properties, their parent/child and multiple inheritance structure, and the distribution of their vertical ranks

Hierarchical Analysis of the Omega Ontology

Initial delivery for mathematical analysis of the Omega Ontology. We provide an analysis of the hierarchical structure of a version of the Omega Ontology currently in use within the US Government. After providing an initial statistical analysis of the distribution of all link types in the ontology, we then provide a detailed order theoretical analysis of each of the four main hierarchical links present. This order theoretical analysis includes the distribution of components and their properties, their parent/child and multiple inheritance structure, and the distribution of their vertical ranks

Littoral and limnetic zooplankton communities in Lake Mead, Nevada-Arizona, USA

Zooplankton were collected from adjacent littoral and limnetic sites in Lake Mead, Nevada-Arizona, USA. Limnetic species dominated both littoral and limnetic zooplankton communities; littoral species rarely exceeded 2% of monthly total zooplankton densities. Low species richness of littoral taxa and high similarity in species composition between littoral and limnetic habitats appeared to result from uniform horizontal physical and chemical environments, due to horizontal mixing, and from the absence aquatic macrophytes. Significant differences in spatial distribution occurred in phytoplankton biomass, total zooplankton density, and fish abundances; highest concentrations of these factors occurred nearest an inflow high in nutrients and progressively declined farther below the inflow. These factors generally showed no significant difference between adjacent littoral and limnetic sites. Large variation also occurred in seasonal zooplankton community structure among some sites

Fish aid: The Lake Mead fertilization project

Sport fishing at Lake Mead in Nevada and Arizona is a resource valued at nearly $100 million per year to southern Nevada. During the past two decades, salmonids, mostly trout, have disappeared entirely, the largemouth bass catch has drastically declined despite greater fishing pressure, and the condition factors for striped bass have steadily deteriorated. It appears that a major reduction in phosphorus loading caused by the upstream impoundment of the Colorado River to form Lake Powell in 1963 and advanced wastewater treatment removal of phosphorus from domestic wastewater inflows in 1981 are the principal factors responsible for decreased production at all levels of the food chain. The Lake Mead Fertilization Project is an attempt to reverse these declining fisheries. The first large-scale test of fertilization occurred on May 30, 1987. More than 300 boats and 1,000 volunteers helped spread 20,000 gallons (75.7 m3) of liquid ammonium polyphosphate over 19,000 acres (7700 ha) of lake surface. Highlights of the history of the project and initial results, which indicate that the test was extremely successful, are discussed

Starspot-induced optical and infrared radial velocity variability in T Tauri star Hubble 4

We report optical (6150 Ang) and K-band (2.3 micron) radial velocities obtained over two years for the pre-main sequence weak-lined T Tauri star Hubble I 4. We detect periodic and near-sinusoidal radial velocity variations at both wavelengths, with a semi-amplitude of 1395\pm94 m/s in the optical and 365\pm80 m/s in the infrared. The lower velocity amplitude at the longer wavelength, combined with bisector analysis and spot modeling, indicates that there are large, cool spots on the stellar surface that are causing the radial velocity modulation. The radial velocities maintain phase coherence over hundreds of days suggesting that the starspots are long-lived. This is one of the first active stars where the spot-induced velocity modulation has been resolved in the infrared.Comment: Accepted for publication in The Astrophysical Journa

Provenance Store Evaluation

Requirements for the provenance store and access API are developed. Existing RDF stores and APIs are evaluated against the requirements and performance benchmarks. The team’s conclusion is to use MySQL as a database backend, with a possible move to Oracle in the near-term future. Both Jena and Sesame’s APIs will be supported, but new code will use the Jena AP

Material Substitution Workshop: Safer Products That Work: Cleaners and Degreasers for Industrial Maintenance and Auto Repair: State/Community Hazardous Material Source Reduction

Presentation details Minnesota Technical Assistance Program's safer chemicals work with auto repair shops and the City of Minneapolis Green Business Cost Share Program. Presented as Day 2 materials substitution workshop at the 2017 Triple Regional Pollution Prevention Roundtable.Ope

Lake Mead prefertilization study: Preliminary nutrient enhancement studies in Lake Mead

Studies conducted by the University of Nevada-Las Vegas (UNLV), the Nevada Department of Wildlife (NDOW), the Arizona Game and Fish Department (AGFD), The Nevada Division of Environmental Protection (NDEP), and the United States Bureau of Reclamation (USBR) have identified decreased algal production as a major factor involved in the decline of the Lake Mead sport fishery. Phosphorus-laden silt particles in the Colorado River have been sedimenting out in Lake Powell since the completion of Glen Canyon Dam 286 miles upstream in 1963. This sharp decrease in phosphorus loading to Lake Mead (\u3e5000 tons per year) has resulted in decreased biomass and growth at all levels of the food chain. Phosphorus loading to the lower basin (Boulder Basin) has decreased even further since 1981 when Clark County and the City of Las Vegas began removing phosphorus from wastewaters discharged into Las Vegas Bay. Most of Lake Mead is now oligotrophic according to almost all of the trophic status indices which have been developed. Only the inner and middle regions of Las Vegas Bay (treated wastewater influent), the Overton Arm upstream of Fish Island (Muddy and Virgin River discharges), and the Iceberg Canyon/Grand Wash area (Colorado River influence) have been found to have phosphorus levels sufficient to sustain relatively higher productivity. Phytoplankton production becomes tightly regulated by the supply of phosphorus during most of the growing season. Zooplankton graze on planktonic algae, and threadfin shad feed primarily on these zooplankton and phytoplankton. Since game fish feed primarily on either zooplankton or shad at different stages of their life cycle, it is clear how a nutrient limitation of phytoplankton growth can cascade up the food chain. The declines in the sport fisheries, particularly largemouth bass, striped bass and trout, began in the early 1960\u27s and have become much more dramatic since the mid to late 1970\u27s as evidenced by declines in total yields of largemouth bass and trout, and striped bass condition factors, and increased angler effort. It is likely that as fish were increasingly stressed by food shortages, conditions were worsened by indirect factors such as lack of suitable cover for littoral populations and by fish predation. The only way to restore the previous fertility of the lake water is to add nutrients. Large-scale fertilization programs in British Columbia and Alaska have been very successful at stimulating the productivity of all levels of the food chain, ultimately producing more salmon. Nevada and Arizona completed an intensive study of the black bass (largemouth bass) fishery in Lake Mead in 1982 which was funded by the U.S. Bureau of Reclamation (USBR). A major recommendation was that pilot fertilizations be conducted as a demonstration project for future large-scale nutrient enrichment. UNLV subsequently submitted a proposal to the Bureau of Reclamation in November 1984 to artificially fertilize about 30,000 acres in the Overton Arm and about 11,000 acres in Gregg Basin. Since that time a technical advisory panel (the Lake Mead Nutrient Enhancement Technical Committee) comprised of representatives from UNLV, NDOW, AGFD, USBR, NDEP, the National Park Service (NPS), and the U.S. Fish and Wildlife Service (USFWS), was formed to review the original proposal and develop a feasible plan for implementing an experimental program of large-scale fertilization. Subsequently, the USBR funded the present study for 16 months (May 1986-August 1987) to conduct laboratory and pilot-scale field experiments designed to evaluate the potential for successfully stimulating algal growth on a large scale in Lake Mead using artificial fertilization

A search for giant planet companions to t tauri stars

We present results from an ongoing multiwavelength radial velocity (RV) survey of the Taurus–Auriga star-forming region as part of our effort to identify pre-main-sequence giant planet hosts. These 1–3 Myr old T Tauri stars present significant challenges to traditional RV surveys. The presence of strong magnetic fields gives rise to large, cool star spots. These spots introduce significant RV jitter which can mimic the velocity modulation from a planet-mass companion. To distinguish between spot-induced and planet-induced RV modulation, we conduct observations at ∼6700Åand∼2.3μmand measure thewavelength dependence (if any) in theRVamplitude. CSHELL observations of the known exoplanet host Gl 86 demonstrate our ability to detect not only hot Jupiters in the near-infrared but also secular trends from more distant companions. Observations of nine very young stars reveal a typical reduction in RV amplitude at the longer wavelengths by a factor of ∼2–3. While we cannot confirm the presence of planets in this sample, three targets show different periodicities in the two wavelength regions. This suggests different physical mechanisms underlying the optical and the K-band variability