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2009

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Articles 5881 - 5910 of 6353

Full-Text Articles in Physical Sciences and Mathematics

Managing Risk In Life Insurance With Your Genetic Information: The Issues, The Options, And The Speed Of Progress, Michelle Gogerty Jan 2009

Managing Risk In Life Insurance With Your Genetic Information: The Issues, The Options, And The Speed Of Progress, Michelle Gogerty

Honors Program Theses

legislation is already in place to restrict the use of genetic information in the health insurance industry (Genetics and Public Policy Center 2008) and several states have similar laws restricting its use in the life insurance industry as well (National Conference of State legislatures 2008}. It is only a matter of time before national legislation applicable to life insurance is enacted on the matter and I expect it to come within the next five years. Unless both insurers and consumers actively protect their rights to privacy, equality, and profitability, the result of that legislation may be very harmful to one …


Spatial, Geologic, And Land Use Characteristics Of Sinkholes In A Karst Landscape: Waverly, Iowa, Adam Richard Campbell Jan 2009

Spatial, Geologic, And Land Use Characteristics Of Sinkholes In A Karst Landscape: Waverly, Iowa, Adam Richard Campbell

Honors Program Theses

The city of Waverly and its surrounding area in the Waverly Quadrangle has the fortune of having a large supply of groundwater that is easily accessible. However, the karst landscape that comprises much of the quadrangle has made the groundwater supply vulnerable to degradation from point and non-point contamination. Thus, it is crucial to explore the properties of sinkholes in the region to determine their threat to groundwater. To determine this threat, it is necessary to examine the characteristics of where and under what circumstances sinkholes develop. The Waverly Quadrangle is located entirely within the Iowan Surface. The bedrock in …


Ambigrams: The Art And The Math, Callie Kronlage Jan 2009

Ambigrams: The Art And The Math, Callie Kronlage

Honors Program Theses

Because ambigrams are a relatively new concept, I found little mathematical research on them. Throughout this paper, I will address the role of ambigrams as a mathematical entity, an artistic outlet, and even an educational tool. Along with ways to use ambigrams, there are also descriptions of the nine different types of ambigrams, and a chart that can be used to create two of the most common types of ambigrams. Mathematically, ambigrams contain many symmetrical aspects, which are important to the study of Geometry. Within this, I have researched mathematical aspects of three of the ambigram types and found some …


Preliminary Development Of Quantitative Immunoassays For Mitochondrial Proteins, Adriann Hovey Jan 2009

Preliminary Development Of Quantitative Immunoassays For Mitochondrial Proteins, Adriann Hovey

Honors Program Theses

Mitochondria are medium-sized organelles in which most cellular metabolic reactions are carried out. In postmitotic cells that are aged or diseased, such as myocardial, skeletal, and brain cells, abnormally large mitochondria ("giant mitochondria") are often observed. Mitochondrial size and shape are controlled by mitochondrial fusion and fission and disruption of this process may lead to their abnormally large size (Nauratil, Terman, Arriaga, 2008). These giant mitochondria exhibit variations from normal metabolism and altered membrane potentials (Nauratil et al., 2008). An increased number of giant mitochondria may therefore disrupt cell function (Nauratil et al., 2008). This accumulation may result either from …


Impacts Of Alterations Of Organic Inputs On The Bacterial Community Within The Sediments Of Wind Cave, South Dakota, Usa, Marisa K. Chelius, Guy Beresford, Howard Horton, Meghan Quirk, Greg Selby, Rodney T. Simpson, Rodney Horrocks, John C. Moore Jan 2009

Impacts Of Alterations Of Organic Inputs On The Bacterial Community Within The Sediments Of Wind Cave, South Dakota, Usa, Marisa K. Chelius, Guy Beresford, Howard Horton, Meghan Quirk, Greg Selby, Rodney T. Simpson, Rodney Horrocks, John C. Moore

International Journal of Speleology

Wind Cave (WICA) in the Black Hills of South Dakota, like many mostly dry caves in temperate regions is an energy-starved system. The biotic communities that reside in these systems are low in diversity and simple in structure, and sensitive to changes in external inputs of organic matter. Caves open to tourist traffic offer an opportunity to study the impacts of organic matter amendments in the form of human and rodent hair and dander, clothing lint, material from rodent activity (nesting materials and feces), and algal growth in and around artificial lighting. This study reports on the impacts of carbon …


Productivity-Diversity Relationships From Chemolithoautotrophically Based Sulfidic Karst Systems, Megan L. Porter, Annette Summers Engel, Thomas C. Kane, Brian K. Kinkle Jan 2009

Productivity-Diversity Relationships From Chemolithoautotrophically Based Sulfidic Karst Systems, Megan L. Porter, Annette Summers Engel, Thomas C. Kane, Brian K. Kinkle

International Journal of Speleology

Although ecosystems thriving in the absence of photosynthetic processes are no longer considered unique phenomena, we have yet to understand how these ecosystems are energetically sustained via chemosynthesis. Ecosystem energetics were measured in microbial mats from active sulfidic caves (Movile Cave, Romania; Frasassi Caves, Italy; Lower Kane Cave, Wyoming, USA; and Cesspool Cave, Virginia, USA) using radiotracer techniques. We also estimated bacterial diversity using 16S rRNA sequences to relate the productivity measurements to the composition of the microbial communities. All of the microbial communities investigated were dominated by chemolithoautotrophic productivity, with the highest rates from Movile Cave at 281 g …


Lights And Shadows On The Conservation Of A Rock Art Cave: The Case Of Lascaux Cave, Fabiola Bastian, Claude Alabouvette Jan 2009

Lights And Shadows On The Conservation Of A Rock Art Cave: The Case Of Lascaux Cave, Fabiola Bastian, Claude Alabouvette

International Journal of Speleology

Lascaux Cave was discovered in 1940. Twenty years after the first microbial contamination signs appeared. In the last forty years the cave suffered different fungal invasions. Here we discuss the past, present and future of the cave and the conservation of its rock art paintings to the light of data obtained using culture-dependent and –independent methods.


Cottonballs, A Unique Subaqeous Moonmilk, And Abundant Subaerial Moonmilk In Cataract Cave, Tongass National Forest, Alaska, Megan D. Curry, Penelope J. Boston, Mike N. Spilde, James F. Baichtal, Andrew R. Campbell Jan 2009

Cottonballs, A Unique Subaqeous Moonmilk, And Abundant Subaerial Moonmilk In Cataract Cave, Tongass National Forest, Alaska, Megan D. Curry, Penelope J. Boston, Mike N. Spilde, James F. Baichtal, Andrew R. Campbell

International Journal of Speleology

The Tongass National Forest is known for its world-class karst features and contains the largest concentration of dissolutional caves in Alaska. Within these karst systems exist unusual and possibly unique formations exhibiting possible biological origin or influence. Cataract Cave is an example of such a system. This cave hosts a unique depositional setting in which so-called “cottonballs” line two permanent pools. The cottonballs are a calcitic deposit heavily entwined within a mass of microbial filaments. They are juxtaposed with extensive subaerial calcitic moonmilk wall deposit of a more conventional nature but of an extraordinary thickness and abundance. Both the cottonballs …


Proceedings Of The 121st Annual Meeting Of The Iowa Academy Of Science [Program, 2009], Iowa Academy Of Science Jan 2009

Proceedings Of The 121st Annual Meeting Of The Iowa Academy Of Science [Program, 2009], Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Welcome from our Campus Host --- 3
Program Summary/Timeline --- 4
General Session Presentations --- 6
Symposia Presentations --- 9
Special Events --- 12
Awards Luncheon --- 13
President's Banquet --- 13
ESTA Awards Banquet --- 13
IAS Annual Business Meeting --- 14
Iowa Junior Academy of Science --- 16
Field Trips --- 17
Senior Poster Program --- 19
Section Meeting Programs and Oral Presentations (Alphabetical by Section) --- 24
Abstracts (by Section) --- 31
Author Index --- 65


Microbial Communities And Associated Mineral Fabrics In Altamira Cave, Spain, Soledad Cuezva, Sergio Sanchez-Moral, Cesareo Saiz-Jimenez, Juan Carlos Cañaveras Jan 2009

Microbial Communities And Associated Mineral Fabrics In Altamira Cave, Spain, Soledad Cuezva, Sergio Sanchez-Moral, Cesareo Saiz-Jimenez, Juan Carlos Cañaveras

International Journal of Speleology

Evidences of microbial colonizations were observed in Altamira Cave, Spain. These consisted of distinct small coloured colonies, both on walls and ceiling, mainly located in the area near the cave entrance, which progressed until reaching the Polychromes Hall. The colonizations were characterized by a high morphological and microstructural variability and related to biomineralization processes. Two main types of CaCO3 deposits were related to the colonies: rosette- or nest-like aggregates of rhombohedral calcite crystals, and spheroid to hemispheroid CaCO3 elements. Colonies distribution seems to be controlled by microenvironmental conditions inside the cavity. The areas of the cave showing higher …


The Association Between Bubble Trails And Folia: A Morphological And Sedimentary Indicator Of Hypogenic Speleogenesis By Degassing, Example From Adaouste Cave (Provence, France), Philippe Audra, Ludovic Mocochain, Jean-Yves Bigot, Jean-Claude Nobécourt Jan 2009

The Association Between Bubble Trails And Folia: A Morphological And Sedimentary Indicator Of Hypogenic Speleogenesis By Degassing, Example From Adaouste Cave (Provence, France), Philippe Audra, Ludovic Mocochain, Jean-Yves Bigot, Jean-Claude Nobécourt

International Journal of Speleology

Bubble trails are subaqueous features in carbonate caves, which are made by the corrosion of ascending carbon dioxide bubbles. Folia are calcite deposits resembling inverted rimstone dams in saturated pools. Based on morphological studies in Adaouste Cave (Provence, France) and on studies elsewhere in the world, we propose a new genetic model for folia, close to the model of Green (1991). The association of bubble trails and folia, occurring on overhanging walls, is interpreted to be an indicator of hypogenic degassing occurring just below the water table. The association is the result of juxtaposed processes composed of corrosion along bubble …


Observations On The Cave-Associated Beetles (Coleoptera) Of Nova Scotia, Canada, Max Moseley Jan 2009

Observations On The Cave-Associated Beetles (Coleoptera) Of Nova Scotia, Canada, Max Moseley

International Journal of Speleology

The cave-associated invertebrates of Nova Scotia constitute a fauna at a very early stage of post-glacial recolonization. The Coleoptera are characterized by low species diversity. A staphylinid Quedius spelaeus spelaeus, a predator, is the only regularly encountered beetle. Ten other terrestrial species registered from cave environments in the province are collected infrequently. They include three other rove-beetles: Brathinus nitidus, Gennadota canadensis and Atheta annexa. The latter two together with Catops gratiosus (Leiodidae) constitute a small group of cave-associated beetles found in decompositional situations. Quedius s. spelaeus and a small suite of other guanophiles live in accumulations of …


Scaling Up Of Co2 Fluxes From Leaf To Canopy In Maize-Based Agroecosystems, Timothy J. Arkebauer, Elizabeth A. Walter-Shea, Mark A. Mesarch, Andrew E. Suyker, Shashi Verma Jan 2009

Scaling Up Of Co2 Fluxes From Leaf To Canopy In Maize-Based Agroecosystems, Timothy J. Arkebauer, Elizabeth A. Walter-Shea, Mark A. Mesarch, Andrew E. Suyker, Shashi Verma

School of Natural Resources: Faculty Publications

Carbon dioxide fluxes are being measured in three maize-based agroecosystems in eastern Nebraska in an effort to better understand the potential for these systems to sequester carbon in the soil. Landscape-level fluxes of carbon, water and energy were measured using tower eddy covariance systems. In order to better understand the landscape-level results, measurements at smaller scales, using techniques promoted by John Norman, were made and scaled up to the landscape-level. Single leaf gas exchange properties (CO2 assimilation rate and stomatal conductance) and optical properties, direct and diffuse radiation incident on the canopy, and photosynthetically active radiation (PAR) reflected and …


Probabilistic Movement Model With Emigration Simulates Movements Of Deer In Nebraska, 1990–2006, Charles J. Frost, Scott E. Hygnstrom, Andrew J. Tyre, Kent M. Eskridge, David M. Baasch, Justin R. Boner, Gregory M. Clements, Jason M. Gilsdorf, Travis C. Kinsell, Kurt C. Vercauteren Jan 2009

Probabilistic Movement Model With Emigration Simulates Movements Of Deer In Nebraska, 1990–2006, Charles J. Frost, Scott E. Hygnstrom, Andrew J. Tyre, Kent M. Eskridge, David M. Baasch, Justin R. Boner, Gregory M. Clements, Jason M. Gilsdorf, Travis C. Kinsell, Kurt C. Vercauteren

School of Natural Resources: Faculty Publications

Movements of deer can affect population dynamics, spatial redistribution, and transmission and spread of diseases. Our goal was to model the movement of deer in Nebraska in an attempt to predict the potential for spread of chronic wasting disease (CWD) into eastern Nebraska. We collared and radio-tracked >600 white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) in Nebraska during 1990–2006.We observed large displacements (>10 km) for both species and sexes of deer, including migrations up to 100 km and dispersals up to 50 km. Average distance traveled between successive daily locations was 166m for …


Effects Of Plant Uptake And Micro-Topography On Chloride Transport In Arid Soils, Wenming Nie Jan 2009

Effects Of Plant Uptake And Micro-Topography On Chloride Transport In Arid Soils, Wenming Nie

UNLV Theses, Dissertations, Professional Papers, and Capstones

Chloride concentration profiles to depths of 1 m were evaluated on a young alluvial fan in Eldorado Valley, NV. It was found that chloride beneath plant canopies were 11 to 222 times higher than adjacent (1 - 2 m away) bare soil locations. Two-dimensional numerical simulations using HYDRUS 2D/3D model were used to further explore the impact of plants on chloride transport. The simulation results indicated that lateral flow driven by root uptake concentrated chloride toward root zones, leading to the accumulation of chloride under plant canopies. Results also suggest that locally micro-topography can have a substantial impact on chloride …


Using Paired Comparison Matrices To Estimate Parameters Of The Partial Credit Rasch Measurement Model For Rater-Mediated Assessments, Mary Garner, George Engelhard Jr. Jan 2009

Using Paired Comparison Matrices To Estimate Parameters Of The Partial Credit Rasch Measurement Model For Rater-Mediated Assessments, Mary Garner, George Engelhard Jr.

Faculty Articles

The purpose of this paper is to describe a technique for estimating the parameters of a Rasch model that accommodates ordered categories and rater severity. The technique builds on the conditional pairwise algorithm described by Choppin (1968, 1985) and represents an extension of a conditional algorithm described by Garner and Engelhard (2000, 2002) in which parameters appear as the eigenvector of a matrix derived from paired comparisons. The algorithm is used successfully to recover parameters from a simulated data set. No one has previously described such an extension of the pairwise algorithm to a Rasch model that includes both ordered …


Bifurcation Analysis Of A Kaldor-Kalecki Model Of Business Cycle With Time Delay, Liancheng Wang, Xiaoqin P. Wu Jan 2009

Bifurcation Analysis Of A Kaldor-Kalecki Model Of Business Cycle With Time Delay, Liancheng Wang, Xiaoqin P. Wu

Faculty Articles

In this paper, we investigate a Kaldor-Kalecki model of business cycle with delay in both the gross product and the capital stock. Stability analysis for the equilibrium point is carried out. We show that Hopf bifurcation occurs and periodic solutions emerge as the delay crosses some critical values. By deriving the normal forms for the system, the direction of the Hopf bifurcation and the stability of the bifurcating periodic solutions are established. Examples are presented to confirm our results.


Positive Solutions For The (N, P) Boundary Value Problem, Bo Yang Jan 2009

Positive Solutions For The (N, P) Boundary Value Problem, Bo Yang

Faculty Articles

We consider the (n, p) boundary value problem in this paper. Some new upper estimates to positive solutions for the problem are obtained. Existence and nonexistence results for positive solutions of the problem are obtained by using the Krasnosel'skii fixed point theorem. An example is included to illustrate the results.


On The Estimation Of Averages Over Infinite Intervals With An Application To Average Persistence In Population Models, Sean F. Ellermeyer Jan 2009

On The Estimation Of Averages Over Infinite Intervals With An Application To Average Persistence In Population Models, Sean F. Ellermeyer

Faculty Articles

We establish a general result for estimating the upper average of a continuous and bounded function over an infinite interval. As an application, we show that a previously studied model of microbial growth in a chemostat with time–varying nutrient input admits solutions (populations) that exhibit weak persistence but not weak average persistence.


Animated Courseware Support For Teaching Database Design, Meg C. Murray, Mario Guimaraes Jan 2009

Animated Courseware Support For Teaching Database Design, Meg C. Murray, Mario Guimaraes

Faculty Articles

Database technologies are a core component of computing technology curricula. Their importance will only continue to expand as more and more data are retained in database systems. An effective database system is predicated on a good data model. Database design is the conceptualization of an underlying data model that progresses from identifying user requirements to graphically depicting those requirements and finally mapping the graphical models to a set of tables implemented in a physical database system. The abstract nature of much of database design makes it challenging to teach. This paper presents a set of software animations designed to support …


Towards Solving Similarity Search Problems Using Fuzzy Concept For Multi-Dimensional Data, Yong Shi Jan 2009

Towards Solving Similarity Search Problems Using Fuzzy Concept For Multi-Dimensional Data, Yong Shi

Faculty Articles

In this paper, we present continuous research on data analysis based on our previous work on similarity search problems. PanKNN[13] is a novel technique which explores the meaning of K nearest neighbors from a new perspective, redefines the distances between data points and a given query point Q, and efficiently and effectively select data points which are closest to Q. It can be applied in various data mining fields. In this paper, we applied the Fuzzy concept to improve the performance of PanKNN, targeting the better decision making for the calculation of the distance between a data …


A Dynamic Insertion Approach For Multi-Dimensional Data Using Index Structures, Yong Shi Jan 2009

A Dynamic Insertion Approach For Multi-Dimensional Data Using Index Structures, Yong Shi

Faculty Articles

Nowadays large volumes of data with high dimensionality are being generated in many fields. Most existing indexing techniques degrade rapidly when dimensionality goes higher. A large amount of data sets are time related, and the existence of the obsolete data in the data sets may seriously degrade the data processing. In our previous work[7], we proposed ClusterTree+, a new indexing approach representing clusters generated by any existing clustering approach. It is a hierarchy of clusters and subclusters which incorporates the cluster representation into the index structure to achieve effective and efficient retrieval. It also has features from the …


An Investigation Of The Ends Of Finitely Generated Groups, Daniel T. Murphree Jan 2009

An Investigation Of The Ends Of Finitely Generated Groups, Daniel T. Murphree

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Geometric group theory is a relatively new branch of mathematics, studied as a distinct area since the 1990's. It explores invariant properties of groups based on group actions defined on topological or geometrical spaces. One of the pioneering works in geometric group theory is the article "Topological Methods in Group Theory" by Peter Scott and Terry Wall, written in 1977. This article was an overview of revised notes from an advanced course give in Liverpool in the same year. This report is an attempt to make these notes more accessible to lower level graduate students in the fields of topology …


Cow Insurance Vs. Human Insurance: A Comparison Study, Corlan Fawcett Jan 2009

Cow Insurance Vs. Human Insurance: A Comparison Study, Corlan Fawcett

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This paper will compare the premiums to insure cows and humans for n-year term, n-year endowment, and whole life insurance. It will go into more depth for whole life premium s that would be charged, such that the insurance company is 95 percent confident that they will not lose money. In particular the paper will look at how the variance affects the premiums for an insurance company insuring 100 cows.


Heritability Of Cognition Subscales In The Cache County Memory Study Cohort And Methods For Estimating Heritability, Colette Kelly Childs Jan 2009

Heritability Of Cognition Subscales In The Cache County Memory Study Cohort And Methods For Estimating Heritability, Colette Kelly Childs

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The rapid improvement of genotyping technology holds the promise of better understanding the genetic causes of complex disease. While traits of interest often include the presence or absence of disease, there is growing interest in intermediate phenotypes (or so-called endophenotypes) that may yield more information about disease onset or course. In particular, changes over time with respect to an investigative ordinal measure often contain significant predictive power, and rate-of-change phenotypes are becoming important in their own right when studying genetic association. Initial steps in assessing the potential genetic determinants of a continuous trait often involve estimating the degree of the …


Comparison Of Random Forests And Cforest: Variable Importance Measures And Prediction Accuracies, Rong Xia Jan 2009

Comparison Of Random Forests And Cforest: Variable Importance Measures And Prediction Accuracies, Rong Xia

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Random forests are ensembles of trees that give accurate predictions for regression, classification and clustering problems. The CART tree, the base learn er employed by random forests, has been criticized because of bias in the selection of splitting variables. The performance of random forests is suspect due to this criticism. A new implementation of random forests, Cforest, which is claimed to outperform random forests in both predictive power and variable importance measures , was developed based on Ctree, an implementation of conditional inference trees.

We address the underlying mechanism of random forests and Cforest in this report. Comparison of random …


Approaches To Promote Active, Conceptual Learning In A Pedagogically Hybrid Introductory Statistics Course, Brittany L. Allred Jan 2009

Approaches To Promote Active, Conceptual Learning In A Pedagogically Hybrid Introductory Statistics Course, Brittany L. Allred

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Statistics education is an active area of research where discovery-based learning is becoming more prominent. This project reviews how the USEI and GAISE recommendations can be implemented in the statistics classroom. Further, the project describes the creation of a library of classroom materials for an introductory statistics course. The results are also discussed from implementing various library materials, along with the student response to hands-on learning techniques.


Logistic Models With Missing Categorical Covariates, Jeremiah Rounds Jan 2009

Logistic Models With Missing Categorical Covariates, Jeremiah Rounds

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

We present an EM based solution to missing categorical covariates in Binomial models with logit links using an assumption that experimental units are drawn from a Multinomial population of infinite size. We further address the problem of separation of points inducing large variances on parameter estimates by the use of a novel score-modification based on Firth's bias-reduction score-modification. We simulate to address questions about estimate bias, distribution, and appropriate parameter coverage by Wald intervals.


Evaluating The Effectiveness Of A Probability Applet, Chelsa Green Tuddenham Jan 2009

Evaluating The Effectiveness Of A Probability Applet, Chelsa Green Tuddenham

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this project was to develop and examine a computerized interactive probability applet designed to teach basic concepts of probability. The applet design was intended to be a user-friendly way to encourage understanding of basic probability concepts such as, rules of probability, probabilities of mutually exclusive events, and the multiplication rule. Thirty participants were recruited from Utah State University and were asked to participate in the evaluation process of the probability applet. The evaluation of the probability applet consisted of three parts: First, a group of participants were video recorded and asked to voice any and all thoughts …


Probe-Level Statistical Models For Differential Expression Of Genes In Bovine Nt Studies, Jason L. Bell Jan 2009

Probe-Level Statistical Models For Differential Expression Of Genes In Bovine Nt Studies, Jason L. Bell

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A brief introduction of microarray technology and its uses is given. This technology is commonly used in agricultural research, including research in nuclear transfer, which motivated this study. There are 3 classes of statistical models compared: probeset-level, weighted probeset-level and probe-level.

Different statistical mod els are compared on 3 spike-in experiments to assess the relative performance in identifying differentially expressed genes . A novel nested factorial model was found to outperform all other models compared in this study in one spike-in experiment, and was found to be competitive in its performance relative to the other models on the other spike-in …