Physical Sciences and Mathematics Commons^™

Influences Of Lithology On Water Quality: A Study Of The Ngam And Mou Watersheds In West Cameroon (Central Africa), E. Kemayou Tchamako, Rv Tsinkou Fotsing, Jp Tchouankoue, Jr Ndam Ngoupayou, B Ngounou Ngatcha, Nancy W. Hinman

Geosciences Faculty Publications

The Ngam and Mou Rivers belong to the river system of the central part of the Cameroon Volcanic Line. The Ngam River watershed comprises 51 Ma old basalts, while the Mou River watershed comprises younger, < 5 Ma pyroclastic basalts. The physico-chemical characteristics of water samples from both watersheds indicated pH between 4.2 and 8.2, and 4.2 to 7.5, and very low mineralization between 11 and 246 μS/cm and 45 to 165 μS/cm, respectively, for the Ngam River and the Mou River. Chemical data showed that waters from old, highly weathered plateau basalts (Ngam River watershed) were dominated by calcium and sodium (signatures of feldpars from syenites and orthogneisses), while waters in the Mou River watershed were dominated by magnesium (signature of olivines and pyroxenes from basalts). Mineralizations in the two watersheds are thus primarily controlled by lithology rather than anthropic activities. These results are promising for identifying potential potable water resources in these areas.

Aluminum In Silica Phases Formed In Hot Springs, Nancy W. Hinman, J. Michelle Kotler

Geosciences Faculty Publications

Sinters are difficult to characterize with traditional methods and are often described by their chemical composition alone. Yet information about the depositional environment and possible diagenetic processes is available in atomic structure. This study probes the atomic structure of siliceous sinters from two geothermal areas using nuclear magnetic resonance (NMR) spectroscopic techniques. Specifically, this study demonstrated that Al is present in tetrahedral coordination with or without octahedral coordination in geyserites from Yellowstone National Park, WY, USA and Geyser Valley, Kamchatka, Russia.

Water-Rock Interaction And Life, Nancy W. Hinman

Geosciences Faculty Publications

Water-rock interactions play a critical role in the origin, existence, and prospects of life. Minerals are sources of energy and nutrients. Life uses aqueous chemical gradients to access and use minerals. Chemical disequilibrium, therefore, represents one type of biotic signature. Life also controls other types of disequilibrium, including isotopic disequilibrium and morphology. Water is a fundamental contributor to all of these biosignatures, acting as a medium for mass transfer and a reservoir for components. Distinguishing biosignatures from abiotic signatures challenges instrumental capabilities. Finally, the ubiquity and heterogenous distribution of life on Earth challenges the ability to interpret different types of …

Indoor Inertial Waypoint Navigation For The Blind, Timothy H. Riehle, Shane M. Anderson, Patrick A. Lichter, William E. Whalen, Nicholas A. Giudice

Spatial Information Science and Engineering Faculty Scholarship

Indoor navigation technology is needed to support seamless mobility for the visually impaired. This paper describes the construction and evaluation of an inertial dead reckoning navigation system that provides real-time auditory guidance along mapped routes. Inertial dead reckoning is a navigation technique coupling step counting together with heading estimation to compute changes in position at each step. The research described here outlines the development and evaluation of a novel navigation system that utilizes information from the mapped route to limit the problematic error accumulation inherent in traditional dead reckoning approaches. The prototype system consists of a wireless inertial sensor unit, …

Class I Waste-Disposal Wells And Class Ii Brine-Injection Wells In Kentucky, Thomas N. Sparks, David C. Harris, J. Richard Bowersox

Map and Chart--KGS

This map shows locations of disposal wells permitted and regulated by the U.S. Environmental Protection Agency under parts of their Underground Injection Control program. Only UIC Class I and Class II disposal wells are illustrated and described. EPA defines Class I as industrial and municipal waste-disposal wells and Class II as oil- and gas-related injection wells (EPA, 2012a). Disposal wells are designed to protect underground sources of drinking water. The primary function of this map is to provide general information about type, name, location, geology, and depth of injection zone for these disposal wells on a statewide basis.

A Spectral Alternative To K-Means Clustering For Graph Data, Becca Simon

Honors Theses, 1963-2015

Producing meaningful clusterings for graph data requires the user to provide some insight to the program which he or she may not have regarding the data. The standard clustering algorithm, K-means, requires the user to specify k, the number of clusters to be produced by the algorithm. This paper discusses the recursivePartition algorithm, a recursive alternative to K-means clustering. The input to recursivePartition asks the user to specify n, the maximum size of any cluster. Using maximum cluster size and spectral methods based on the Laplacian matrix of the graph, recursivePartition has demonstrated an ability to produce highly …

Artificial Intelligence And Data Mining: Algorithms And Applications, Jianhong Xia, Fuding Xie, Yong Zhang, Craig Caulfield

Research outputs 2013

Artificial intelligence and data mining techniques have been used in many domains to solve classification, segmentation, association, diagnosis, and prediction problems. The overall aim of this special issue is to open a discussion among researchers actively working on algorithms and applications. The issue covers a wide variety of problems for computational intelligence, machine learning, time series analysis, remote sensing image mining, and pattern recognition. After a rigorous peer review process, 20 papers have been selected from 38 submissions. The accepted papers in this issue addressed the following topics: (i) advanced artificial intelligence and data mining techniques; (ii) computational intelligence in …

Treatment Of Synthetic Urban Runoff Using Manganese Oxide-Coated Sand In The Presence Of Magnetic Field, Maryam Foroughi, Mehdi Khiadani, Mohammad Mehdi Amin, Hamid Reza Pourzamani, Marzieh Vahid Dastjerdi

Research outputs 2013

Aims: The purpose of this study was to investigate the efficiency of manganese oxide‑coated sand in the presence of magnetic field to treat urban runoff. Materials and Methods: A flow‑through column having a diameter of 50 mm was filled with coated sand and used to conduct the experiments in this study. Atomic absorption, turbidimeter, pH meter, and spectrophotometer DR5000 were used to measure heavy metals, turbidity, pH, phosphate, and nitrate, respectively. The surface of coated sand was assessed by SEM. Energy dispersive X‑ray analysis (EDAX) analysis was used to determine percentage of sand components. Results: SEM and EDAX analyses confirmed …

Projected Risks To Groundwater-Dependent Terrestrial Vegetation Caused By Changing Climate And Groundwater Abstraction In The Central Perth Basin, Western Australia, Olga Barron, Raymond H. Froend, Geoff Hodgson, Riasat Ali, Warrick Dawes, Phil Davies, Don Macfarlane

Research outputs 2013

The effect of potential climate change on groundwater-dependent vegetation largely depends on the nature of the climate change (drying or wetting) and the level of current ecosystem dependence on groundwater resources. In south-western Australia, climate projections suggest a high likelihood of a warmer and drier climate. The paper examines the potential environmental impacts by 2030 at the regional scale on groundwater-dependent terrestrial vegetation (GDTV) adapted to various watertable depths, on the basis of the combined consideration of groundwater modelling results and the framework for GDTV risk assessment. The methodology was tested for the historical period from 1984 to 2007, allowing …

Meta-Analysis Reveals Complex Marine Biological Responses To The Interactive Effects Of Ocean Acidification And Warming, Ben P. Harvey, Dylan Gwynn-Jones, Philippa J. Moore

Research outputs 2013

Ocean acidification and warming are considered two of the greatest threats to marine biodiversity, yet the combined effect of these stressors on marine organisms remains largely unclear. Using a meta-analytical approach, we assessed the biological responses of marine organisms to the effects of ocean acidification and warming in isolation and combination. As expected biological responses varied across taxonomic groups, life-history stages, and trophic levels, but importantly, combining stressors generally exhibited a stronger biological (either positive or negative) effect. Using a subset of orthogonal studies, we show that four of five of the biological responses measured (calcification, photosynthesis, reproduction, and survival, …

Mine Closure Of Pit Lakes As Terminal Sinks: Best Available Practice When Options Are Limited?, Clinton D. Mccullough, G. Marchand, J Unseld

Research outputs 2013

In an arid climate, pit lake evaporation rates can exceed influx rates, causing the lake to function as a hydraulic terminal sink, with water levels in the pit remaining below surrounding groundwater levels. We present case studies from Western Australia for two mines nearing closure. At the first site, modelling indicates that waste dump covers for the potentially acid forming (PAF) material would not be successful over the long term (1,000 years or more). The second site is a case study where PAF management is limited by the current waste rock dump location and suitable cover materials. Pit lake water …

Use Of Sweet Potato To Develop A Medium For Cultivation Of Lactic Acid Bacteria, Saeed A. Hayek

Dissertations

This study investigated the use of sweet potatoes (Ipomoea batatas) as a basic component to develop a medium for cultivation of lactic acid bacteria (LAB). Extract from baked sweet potatoes was used to form a sweet potato medium (SPM). SPM was supplemented with 4 g/L of each nitrogen source (beef extract, yeast extract, and proteose peptone #3). Lactobacilli MRS was used as a control medium. Ten LAB strains were used to determine the suitability of SPM serving the growth of LAB. Our results showed no significant (p < 0.05) differences in the optical density, maximum specific growth rates, and bacterial populations between MRS and SPM. SPM also maintained higher pH values throughout the incubation period compared to that in MRS. The cost of SPM was 47% less than the cost of MRS. Further step was taken to determine the suitability of SPM serving LAB enzymatic activity. LAB strains growing in SPM showed relatively higher β-glucosidases, acid phosphatase, and phytase activities and lower a-glucosidase compared to that in MRS. Strains of L. reuteri showed the …

The Vascular Flora Of Clay Prairie State Preserve (Butler County, Iowa): Recommendations To The Iowa State Preserve System, Edwin L. Freese, William R. Norris

Journal of the Iowa Academy of Science: JIAS

Clay Prairie State Preserve (1.2 ha) is an upland prairie located in Butler County, IA, and represents one of the last remnants of black-soil tallgrass prairie in northeast Iowa. An annotated checklist of the vascular flora of Clay Prairie is presented here, based on a previously published flora of the preserve and recent field work conducted by the authors between 1997 to 2001, and 2008 to 2011. The preserve contains a diverse vascular flora representing 50 families, 145 genera and 214 taxa (174 native to Iowa). In comparison with 26 larger prairies (4 to 121 ha) protected in the Iowa …

The Psychological Impacts Of False Positive Ovarian Cancer Screening: Assessment Via Mixed And Trajectory Modeling, Amanda T. Wiggins

Theses and Dissertations--Epidemiology and Biostatistics

Ovarian cancer (OC) is the fifth most common cancer among women and has the highest mortality of any cancer of the female reproductive system. The majority (61%) of OC cases are diagnosed at a distant stage. Because diagnoses occur most commonly at a late-stage and prognosis for advanced disease is poor, research focusing on the development of effective OC screening methods to facilitate early detection in high-risk, asymptomatic women is fundamental in reducing OC-specific mortality. Presently, there is no screening modality proven efficacious in reducing OC-mortality. However, transvaginal ultrasonography (TVS) has shown value in early detection of OC. TVS presents …

Data Mining And Pattern Discovery Using Exploratory And Visualization Methods For Large Multidimensional Datasets, Hsin-Fang Li

Theses and Dissertations--Epidemiology and Biostatistics

Oral health problems have been a major public health concern profoundly affecting people’s general health and quality of life. Given that oral health data is composed of several measurable dimensions including clinical measurements, socio-behavioral factors, genetic predispositions, self-reported assessments, and quality of life measures, strategies for analyzing multidimensional data are neither computationally straightforward nor efficient. Researchers face major challenges to identify tools that circumvent the processes of manually probing the data.

The purpose of this dissertation is to provide applications of the proposed methodology on oral health-related data that go beyond identifying risk factors from a single dimension, and to …

Post-Caledonian Brittle Fault Zones On The Hyperextended Sw Barents Sea Margin: New Insights Into Onshore And Offshore Margin Architecture, Kjetil Indrevær, Steffen G. Bergh, Jean-Baptiste Koehl, John-Are Hansen, Elizabeth R. Schermer, Arild Ingebrigtsen

Geology Faculty Publications

Onshore-offshore correlation of brittle faults and tectonic lineaments has been undertaken along the SW Barents Sea margin off northern Norway. The study has focused on onshore mapping of fault zones, the mapping of offshore fault complexes and associated basins from seismic interpretation, and the linkage of fault complexes onshore and offshore by integrating a high-resolution DEM, covering both onshore and offshore portions of the study area, and processed magnetic anomaly data. This study shows that both onshore and offshore brittle faults manifest themselves mainly as alternating NNE–SSW- and ENE–WSW-trending, steeply to moderately dipping, normal fault zones constituting at least two …

Chemistry Of Impact-Generated Silicate Melt-Vapor Debris Disks, Channon Visscher, Bruce Fegley Jr.

Faculty Work Comprehensive List

In the giant impact theory for lunar origin, the Moon forms from material ejected by the impact into an Earth-orbiting disk. Here we report the initial results from a silicate melt-vapor equilibrium chemistry model for such impact-generated planetary debris disks. In order to simulate the chemical behavior of a two-phase (melt+vapor) disk, we calculate the temperature-dependent pressure and chemical composition of vapor in equilibrium with molten silicate from 2000 to 4000 K. We consider the elements O, Na, K, Fe, Si, Mg, Ca, Al, Ti, and Zn for a range of bulk silicate compositions (Earth, Moon, Mars, eucrite parent body, …

Research Report 2013-2014, College Of Arts And Sciences

Physics Research Reports

• Introduction
• From the Chai
• Research Spotlight: Elena Litvinova, Ph.D.
• Refereed Publications
• Invited Presentations
• Contributed Presentations
• External Grant Activity (Submitted and Awarded)
• Notable Awards and Memberships
• Doctoral Dissertations and Master’s Theses
• Department Personnel

Oxidation Of Gold Clusters By Thiols, Brian M. Barngrover, Christine M. Aikens

Faculty Publications

The formation of gold–thiolate nanoparticles via oxidation of gold clusters by thiols is examined in this work. Using the BP86 density functional with a triple ζ basis set, the adsorption of methylthiol onto various gold clusters Au_n^Z (n = 1–8, 12, 13, 20; Z = 0, −1, +1) and Au₃₈⁴⁺ is investigated. The rate-limiting step for the reaction of one thiol with the gold cluster is the dissociation of the thiol proton; the resulting hydrogen atom can move around the gold cluster relatively freely. The addition of a second thiol can lead to H_{2 …}

Comparison And Evaluation Of Black Carbon And Elemental Carbon Instrumentation In A Near Roadway Environment, Brandon James Feenstra

Theses Digitization Project

This study was conducted at a site adjacent to the I-710 freeway in Long Beach California from March 7 to April 8 of 2012 to evaluate various black carbon and elemental carbon aerosol measurement methods. The measurement of carbonaceous aerosol is a growing field of study because of increasing interest into the climate and health effects of black carbon (BC), and important constituent of atmospheric particular matter (PM). Elemental carbon (EC) and BC are measurements of similar portions of carbon particulate matter, but two measures are operationally defined according to the method used for their detection.

A Study Of Finite Symmetrical Groups, May Majid

Theses Digitization Project

This study investigated finite homomorphic images of several progenitors, including 2*⁵ : S₅, 2*⁶ : A₆, and 3*⁵ : C₅ The technique of manual of double coset enumeration is used to construct several groups by hand and computer-based proofs are given for the isomorphism types of the groups that are not constructed.

Developing Focused Auditing Tools: A Practical Framework For Creating Formalized Multi-Level Security Policy Specifications, Barbara Ann Brough

Theses Digitization Project

The purpose of this study is that formalized policy specifications and focused penetration testing are needed to effectively audit any information system. Designing and maintaining the security system information is the primary duty of the cyber security professional. In today's world, nearly all government agencies manage some form of financial, defense, national security, and/or privacy information security policies. It is also necessary in this environment that agencies are accountable for auditing the security systems that protect this information.

The Implementation Of A Thin Client In The Department Of Defense Network System, Sung Ju In

Theses Digitization Project

The purpose of this project is to introduce and analyze a thin client solution that could enhance the overall Department of Defense (DoD) network system as well as its IT security posture, minimize risk from external threats, and ease of network operations.

Asynchronous Cellular Automata, Kelechi Chidi Anuforo

Theses Digitization Project

This study will investigate floating-point asynchronous cellular automata models implemented on Field-Programmable Gate Array (FPGA). It includes single grid and random schedules for individual cells. Cellular automata (CA) are basic representations of calculations that show interesting elaborate responses.

The Parsec-Scale Structure Of The Newer Tev Blazars, Glenn Piner

Physics

We expand our previous studies of the parsec-scale structure of TeV blazars by presenting first- epoch images from VLBA monitoring of ten newer TeV HBLs. All ten sources were successfully detected and imaged, and all showed a one-sided core-jet structure. Many display a morphology common to TeV HBLs: a short, collimated jet followed by a transition to low surface brightness extended emission with a much broader opening angle. The newly detected TeV HBLs tend to be fainter in the radio; the median core flux density was 22 mJy, and the median brightness temperature was 8 × 109 K. The brightness …

Magnetic Tuning Of Plasmonic Excitation Of Gold Nanorods, Serkan Zorba, Mingsheng Wang, Chuanbo Gao, Le He, Jinzhong Zhang, Chi Tang, Yadong Yin

Physics

By using gold nanorods as an example, we report the dynamic and reversible tuning of the plasmonic property of anisotropically shaped colloidal metal nanostructures by controlling their orientation using external magnetic fields. The magnetic orientational control enables instant and selective excitation of the plasmon modes of AuNRs through the manipulation of the field direction relative to the directions of incidence and polarization of light.

The Geologic Records Of Dust In The Quaternary, Daniel R. Muhs

United States Geological Survey: Staff Publications

Study of geologic records of dust composition, sources and deposition rates is important for understanding the role of dust in the overall planetary radiation balance, fertilization of organisms in the world’s oceans, nutrient additions to the terrestrial biosphere and soils, and for paleoclimatic reconstructions. Both glacial and non-glacial processes produce fine-grained particles that can be transported by the wind. Geologic records of dust flux occur in a number of depositional archives for sediments: (1) loess deposits; (2) lake sediments; (3) soils; (4) deep-ocean basins; and (5) ice sheets and smaller glaciers. These archives have several characteristics that make them highly …

Modeling Rain-Fed Maize Vulnerability To Droughts Using The Standardized Precipitation Index From Satellite Estimated Rainfall-Southern Malawi Case Study, Harikishan Jayanthi, Gregory J. Husak, Chris Funk, Tamuka Magadzire, Adams Chavula, James P. Verdin

United States Geological Survey: Staff Publications

During 1990s, disaster risk reduction emerged as a novel, proactive approach to managing risks from natural hazards. The World Bank, USAlD, and other international donor agencies began making efforts to mainstream disaster risk reduction in countries whose population and economies were heavily dependent on rain-fed agriculture. This approach has more significance in light of the increasing climatic hazard patterns and the climate scenarios projected for different hazard prone countries in the world. The Famine Early Warning System Network (FEWS NET) has been monitoring the food security issues in the sub-Saharan Africa, Asia and in Haiti. FEWS NET monitors the rainfall …

Loess Origin, Transport, And Deposition Over The Past 10,000 Years, Wrangell-St. Elias National Park, Alaska, Daniel R. Muhs, James R. Budahn, John P. Mcgeehin, E. Arthur Bettis Iii, Gary Skipp, James B. Paces, Elisabeth A. Wheeler

United States Geological Survey: Staff Publications

Contemporary glaciogenic dust has not received much attention, because most research has been on glaciogenic dust of the last glacial period or non-glaciogenic dust of the present interglacial period. Nevertheless, dust from modern glaciogenic sources may be important for Fe inputs to primary producers in the ocean. Adjacent to the subarctic Pacific Ocean, we studied a loess section near Chitina, Alaska along the Copper River in Wrangell-St. Elias National Park, where dust has been accumulating over the past ~10,000 years. Mass accumulation rates for the fine-grained (<20 >µm) fraction of this loess section are among the highest reported for the …

Chronology And Provenance Of Last-Glacial (Peoria) Loess In Western Iowa And Paleoclimatic Implications, Daniel R. Muhs, E. Arthur Bettis Iii, Helen M. Roberts, Stephen S. Harlan, James B. Paces, Richard L. Reynolds

United States Geological Survey: Staff Publications

Geologic archives show that the Earth was dustier during the last glacial period. One model suggests that increased gustiness (stronger, more frequent winds) enhanced dustiness. We tested this at Loveland, Iowa, one of the thickest deposits of last-glacial-age (Peoria) loess in the world. Based on K/Rb and Ba/Rb, loess was derived not only from glaciogenic sources of the Missouri River, but also distal loess from non-glacial sources in Nebraska. Optically stimulated luminescence (OSL) ages provide the first detailed chronology of Peoria Loess at Loveland. Deposition began after ~27 ka and continued until ~17 ka. OSL ages also indicate that mass …