Physical Sciences and Mathematics Commons^™

The Global Status Of Freshwater Fish Age Validation Studies And A Prioritization Framework For Further Research, Jonathan J. Spurgeon, Martin J. Hamel, Kevin L. Pope, Mark A. Pegg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Age information derived from calcified structures is commonly used to estimate recruitment, growth, and mortality for fish populations. Validation of daily or annual marks on age structures is often assumed, presumably due to a lack of general knowledge concerning the status of age validation studies. Therefore, the current status of freshwater fish age validation studies was summarized to show where additional effort is needed, and increase the accessibility of validation studies to researchers. In total, 1351 original peer-reviewed articles were reviewed from freshwater systems that studied age in fish. Periodicity and age validation studies were found for 88 freshwater species …

Barriers And Bridges To The Integration Of Social–Ecological Resilience And Law, Olivia Odom Green, Ahjond S. Garmestani, Craig R. Allen, Lance H. Gunderson, J.B. Ruhl, Craig A. Arnold, Nicholas A.J. Graham, Barbara Cosens, David G. Angeler, Brian C. Chaffin, C.S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

There is a fundamental difference between the ways in which ecologists and lawyers view uncertainty: in the study of ecology, uncertainty provides a catalyst for exploration, whereas uncertainty is antithetical to the rule of law. This issue is particularly troubling in environmental management, where the tensions between law and ecology become apparent. Rather than acknowledge uncertainties in management actions, legal frameworks often force a false sense of certainty in linking cause and effect. While adaptive management has been developed to deal with uncertainty, laws and legal wrangling can be obstacles to implementation. In this article, we recommend resilience-based governance – …

Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term …

Across-Ecoregion Analysis Suggests A Hierarchy Of Ecological Filters That Regulate Recruitment Of A Globally Invasive Fish, Przemek G. Bajer, Timothy K. Cross, Joseph D. Lechelt, Christopher J. Chizinski, Michael J. Weber, Peter W. Sorensen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Aim -- Even successful invaders are abundant only in a fraction of locales they inhabit. One of the main challenges in invasion ecology is explaining processes that drive these patterns. We investigated recruitment of a globally invasive fish, common carp (Cyprinus carpio), across three ecoregions to determine the role of environmental characteristics, predatory communities and propagule pressure on the invasion process at coarse and fine spatial scales.

Location -- Lakes across Northern Forest, Temperate Forest and Great Plains ecoregions of North America.

Methods -- We used data from 567 lakes to model presence or absence of carp recruitment …

The Importance Of Scaling For Detecting Community Patterns: Success And Failure In Assemblages Of Introduced Species, Craig R. Allen, David G. Angeler, Michael P. Moulton, Crawford S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Community saturation can help to explain why biological invasions fail. However, previous research has documented inconsistent relationships between failed invasions (i.e., an invasive species colonizes but goes extinct) and the number of species present in the invaded community. We use data from bird communities of the Hawaiian island of Oahu, which supports a community of 38 successfully established introduced birds and where 37 species were introduced but went extinct (failed invasions). We develop a modified approach to evaluate the effects of community saturation on invasion failure. Our method accounts (1) for the number of species present (NSP) when the species …

The Effects Of Harvest Regulations On Behaviors Of Duck Hunters, Matthew T. Haugen, Larkin A. Powell, Mark P. Vrtiska, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Uncertainty exists as to how duck harvest regulations influence waterfowl hunter behavior. We used the U.S. Fish and Wildlife Service’s Parts Collection Survey to examine how harvest regulations affected behaviors of Central Flyway duck hunters. We stratified hunters into ranked groups based on seasonal harvest and identified three periods (1975–1984, 1988–1993, 2002–2011) that represented different harvest regulations (moderate, restrictive, and liberal, respectively; season length and daily bag limits smallest in restrictive seasons and largest in liberal seasons). We examined variability of seven measures of duck hunter behaviors across the periods: days harvesting ducks, daily harvest, hunter mobility, mallard (Anas platyrhynchos …

Accuracy Or Precision: Implications Of Sample Design And Methodology On Abundance Estimation, Lucas K. Kowalewski, Christopher J. Chizinski, Larkin A. Powell, Kevin L. Pope, Mark A. Pegg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Sampling by spatially replicated counts (point-count) is an increasingly popular method of estimating population size of organisms. Challenges exist when sampling by point-count method, and it is often impractical to sample entire area of interest and impossible to detect every individual present. Ecologists encounter logistical limitations that force them to sample either few large-sample units or many small sample-units, introducing biases to sample counts. We generated a computer environment and simulated sampling scenarios to test the role of number of samples, sample unit area, number of organisms, and distribution of organisms in the estimation of population sizes using N-mixture …

Predictions Of Future Ephemeral Springtime Waterbird Stopover Habitat Availability Under Global Change, Daniel R. Uden, Craig R. Allen, Andrew A. Bishop, Roger Grosse, Christopher F. Jorgensen, Theodore G. Lagrange, Randy G. Stutheit, Mark P. Vrtiska

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In the present period of rapid, worldwide change in climate and landuse (i.e., global change), successful biodiversity conservation warrants proactive management responses, especially for long-distance migratory species. However, the development and implementation of management strategies can be impeded by high levels of uncertainty and low levels of control over potentially impactful future events and their effects. Scenario planning and modeling are useful tools for expanding perspectives and informing decisions under these conditions. We coupled scenario planning and statistical modeling to explain and predict playa wetland inundation (i.e., presence/absence of water) and ponded area (i.e., extent of water) in the Rainwater …

Drougthscape- Winter 2015, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

CONTENTS

Director’s report...........................1

Central U.S. 2012 report..............3

Oct.-Dec. drought summary ........ 4

2014 drought summary................6

Caribbean capacity building ........ 8

Drought impacts in 2014..............9

California timeline 2014.............12

UC Davis ranching workshop .... 14

NASA SMAP data......................16

Global drought info system........17

Community Capitals .................. 18

Evaluation and assessment.......19

Indicator-impact research .........20

NDMC on YouTube....................21

Room-Temperature Distance Measurements Of Immobilized Spin-Labeled Protein By Deer/Peldor, Virginia Meyer, Michael A. Swanson, Laura J. Clouston, Przemysław J. Boratyński, Richard A. Stein, Hassane S. Mchaourab, Andrzej Rajca, Sandra S. Eaton, Gareth R. Eaton

Andrzej Rajca Publications

Nitroxide spin labels are used for double electron-electron

resonance (DEER) measurements of distances between sites in

biomolecules. Rotation of gem-dimethyls in commonly used

nitroxides causes spin echo dephasing times (T_m) to be too

short to perform DEER measurements at temperatures between

∼80 and 295 K, even in immobilized samples. A spirocyclohexyl

spin label has been prepared that has longer T_m between 80

and 295 K in immobilized samples than conventional labels. Two

of the spirocyclohexyl labels were attached to sites on T4 lysozyme introduced by site-directed spin labeling. Interspin

distances up to ∼4 nm were …

Change Point Detection And Estimation In Sequences Of Dependent Random Variables, Benjamin Cortese

Dissertations - ALL

Two change point detection and estimation procedures for sequences of dependent binary random variables are proposed and their asymptotic properties are explored. The two procedures are a dependent cumulative sum statistic (DCUSUM) and a dependent likelihood ratio test (LRT) statistic, which are generalizations of the independent CUSUM and LRT statistics.

A one step Markov dependence is assumed between consecutive variables in the sequence, and the performance of the DCUSUM and dependent LRT are shown to have substantially better size and power performance than their independent counterparts. In most cases, a comparison of the dependent procedures via simulation shows that the …

Spin-Modified Catalysis, R Choudhary, Priyanka Manchanda, Axel Enders, Balamurugan Balamurugan, Arti Kashyap, David J. Sellmyer, Ralph A. Skomski

Ralph Skomski Publications

First-principle calculations are used to explore the use of magnetic degrees of freedom in catalysis. We use the Vienna Ab-Initio Simulation Package to investigate both L10-ordered FePt and CoPt bulk materials and perform supercell calculations for FePt nanoclusters containing 43 atoms. As the catalytic activity of transition-metal elements and alloys involves individual d levels, magnetic alloying strongly affects the catalytic performance, because it leads to shifts in the local densities of states and to additional peaks due to magnetic-moment formation. The peak shift persists in nanoparticles but is surface-site specific and therefore depends on cluster size. Our research indicates that …

Correlations In Rare-Earth Transition-Metal Permanent Magnets, Ralph Skomski, Priyanka Manchanda, Arti Kashyap

Ralph Skomski Publications

It is investigated how electron-electron correlations affect the intrinsic properties of rare-earth transition- metal magnets. Focusing on orbital moment and anisotropy, we perform model calculations for 3d-4f alloys and density-functional theory (DFT) calculations for NdCo5. On an independentelectron level, the use of a single Slater determinant with broken spin symmetry introduces Hund’s rule correlations, which govern the behavior of rare-earth ions and of alloys described by the local spin density approximation (LSDA) and LSDAþU approximations to DFT. By contrast, rareearth ions in intermetallics involve configuration interactions between two or more Slater determinants and lead to phenomena such as spin-charge distribution. …

Beyond Standard Model Physics Under The Ground And In The Sky, Bithika Jain

Dissertations - ALL

Cosmology and particle physics are in an exciting data-rich era, with several collider and astronomical searches underway. In this dissertation, we have explored some problems which are not addressed by the standard models of particle physics and cosmology. The implications of the Higgs discovery and lack of new physics results are far reaching. To better understand the nature of Higgs and its connections to electroweak symmetry breaking, we have performed a model independent study of spin-1 contributions in gauge extensions of Standard model. The null results of all low energy supersymmetric searches has lead to the development of Split SUSY …

Establishing A Framework For The Recognition Of Local Arboricultural Practitioners, Paul Yuen King Chan

Faculty of Design & Environment (THEi)

No abstract provided.

Image Denoising By A Local Clustering Framework, Partha Sarathi Mukherjee, Peihua Qiu

Mathematics Faculty Publications and Presentations

Images often contain noise due to imperfections in various image acquisition techniques. Noise should be removed from images so that the details of image objects (e.g., blood vessels, inner foldings, or tumors in the human brain) can be clearly seen, and the subsequent image analyses are reliable. With broad usage of images in many disciplines—for example, medical science—image denoising has become an important research area. In the literature, there are many different types of image denoising techniques, most of which aim to preserve image features, such as edges and edge structures, by estimating them explicitly or implicitly. Techniques based on …

Climate Anomalies And Primary Production In Lake Superior, Marcel L. Dijkstra

Dissertations, Master's Theses and Master's Reports - Open

This dissertation supports the modeling of primary production in Lake Superior by offering site specific kinetics and algorithms developed from lab experiments performed on the natural phytoplankton assemblage of Lake Superior. Functions, developed for temperature, light and nutrient conditions and the maximum specific rate of primary production, were incorporated in a 1D specific primary production model and confirmed to published in-situ measured rates of primary production.

An extensive data set (supporting model calibration and confirmation), with a fine spatiotemporal resolution, was developed from field measurements taken bi-weekly during the sampling seasons of 2011, 2012 and 2014; considered to be meteorologically …

Characterization Of Transport And Transformation Of Air Pollutants Observed In The Free Troposphere Over The Central North Atlantic, Bo Zhang

Dissertations, Master's Theses and Master's Reports - Open

Long-range transport of continental pollution emissions has been found to affect air quality in the downwind regions. The Pico Mountain Observatory (PMO), which was established in 2001 in the Azores Islands, has been a perfect site to study long range transport from North America to the central North Atlantic. The dissertation uses the observations and modeling products created since 2001 to provide insights on ozone production tendency during transport, trace gases observations for varying transport patterns, and aerosol ages in the free troposphere over the central North Atlantic.

The first phase of this dissertation research focused on determining the causes …

An Application Of The Autism Management Platform To Tracking Student Progress In The Special Education Environment, Ryan Thomas Burns

Computational and Data Sciences Theses

In the age of online courses and digital textbooks, several areas of academia, such as special education, are far behind in the technological revolution. Some teachers use long unstructured digital documents, while others maintain large physical files for students containing every piece of information or coursework they have ever received. Could these extremely unstructured approaches to data collection and aggregation be streamlined with a software platform built specifically for this purpose? Could this platform also be built to accommodate multiple integrations and practical new features? Most importantly, in terms of usability, would this software be enjoyable to use? The Autism …

Total Synthesis Of Syringolides 1 And 2, Sudhakar Kalagara

Open Access Theses & Dissertations

The total synthesis of Syringolides is described. The synthetic pathway was designed in order to synthesize Syringolides in high yields using inexpensive starting materials. The synthesis strategy features a preparation of the linear tricarbonyl compound followed by intramolecular cyclization. The linear precursor is divided into two fragments, β-keto acid and protected D-xylulose, which are the key fragments and were synthesized from α,β-unsaturated compound followed by asymmetric dihydroxylation. The α,β-unsaturated compound was efficiently prepared by a Wittig reaction between aldehyde and ylide fragments. The butenolide derivative was also achieved by the Knoevenagel condensation of the tricarbonyl compound.

Bayesian Adaptive Penalized Splines In Nonparametric Regression And In Spectral Time Series Analysis, Luis Angel Mora

Open Access Theses & Dissertations

A Bayesian approach to nonparametric regression using Penalized splines (P-splines) is presented. The approach uses the linear mixed model formulation of P-spines. The usual model assumes a single value for the smoothing parameter controlling the amount of smoothing of the fitted function. The main focus of the Thesis is on spatially adaptive smoothing where the smoothing parameter is a function of the covariate so that different amounts of smoothing are applied in different regions of the covariate. An application to spectral time series analysis will be demonstrated. Markov chain Monte Carlo methods are used to make inference based on the …

The Importance Of Olfactory And Visual Cues In Developing Better Monitoring Tools For Sirex Noctilio (Hymenoptera: Siricidae), Mark A. Sarvary, Miriam F. Cooperband, Ann E. Hajek

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

1. To improve the monitoring of the invasive European woodwasp, both sexes of Sirex noctilio were studied in a walk-in wind tunnel.We evaluated three trap types: unbaited traps, traps baited with a three-component pheromone lure and traps baited with a commercial Sirex kairomone lure and ultraviolet light.

2. When no lure was present, the black intercept trap caught more females than the clear jar trap. The increase in pheromone concentration from 0.1 to 1mg increased the capture of females, and not males, in the black intercept panel trap. Both of these findings suggest that the visual cues provided by the …

Mod Planes: A New Dimension To Modulo Theory, Florentin Smarandache, W.B. Vasantha Kandasamy, K. Ilanthenral

Branch Mathematics and Statistics Faculty and Staff Publications

In this book for the first time authors study mod planes using modulo intervals [0, m); 2 ≤ m ≤ ∞. These planes unlike the real plane have only one quadrant so the study is carried out in a compact space but infinite in dimension. We have given seven mod planes viz real mod planes (mod real plane) finite complex mod plane, neutrosophic mod plane, fuzzy mod plane, (or mod fuzzy plane), mod dual number plane, mod special dual like number plane and mod special quasi dual number plane. These mod planes unlike real plane or complex plane or neutrosophic …

Scientific Evidence Supports A Ban On Microbeads, Cm Rochman, Sm Kross, Jb Armstrong, Mt Bogan, Es Darling, Sj Green, Ar Smyth, D Verissimo

VIMS Articles

No abstract provided.

Genomic-Enabled Prediction Of Ordinal Data With Bayesian Logistic Ordinal Regression, Osval A. Montesinos-López, Abelardo Montesinos-López, José Crossa, Juan Burgueño, Kent M. Eskridge

Department of Statistics: Faculty Publications

Most genomic-enabled prediction models developed so far assume that the response variable is continuous and normally distributed. The exception is the probit model, developed for ordered categorical phenotypes. In statistical applications, because of the easy implementation of the Bayesian probit ordinal regression (BPOR) model, Bayesian logistic ordinal regression (BLOR) is implemented rarely in the context of genomic-enabled prediction [sample size (n) is much smaller than the number of parameters (p)]. For this reason, in this paper we propose a BLOR model using the Pólya-Gamma data augmentation approach that produces a Gibbs sampler with similar full conditional distributions of the BPORmodel …

Establishment And Persistence Of Yellow-Flowered Alfalfa No-Till Interseeded Into Crested Wheatgrass Stands, Christopher G. Misar, Lan Xu, Roger N. Gates, Arvid Boe, Patricia S. Johnson, Christopher S. Schauer, John R. Rickertsen, Walter Stroup

Department of Statistics: Faculty Publications

Crested wheatgrass [Agropyron cristatum (L.) Gaertn., A. desertorum

(Fisch. ex Link) Schult., and related taxa] often exists

in near monoculture stands in the northern Great Plains.

Introducing locally adapted yellow-flowered alfalfa [Medicago

sativa L. subsp. falcata (L.) Arcang.] would complement crested

wheatgrass. Our objective was to evaluate effects of seeding

date, clethodim {(E) -2-[1-[[(3-chloro-2-propenyl)oxy]imino]

propyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one}

sod suppression, and seeding rate on initial establishment and

stand persistence of Falcata, a predominantly yellow-flowered

alfalfa, no-till interseeded into crested wheatgrass. Research was

initiated in August 2008 at Newcastle, WY; Hettinger, ND;

Fruitdale, SD; and Buffalo, SD. Effects of treatment …

Effect Of Dexamethasone Prodrug On Inflamed Temporomandibular Joints In Juvenile Rats, Mitchell Knudsen, Matthew Bury, Callie Holwegner, Adam L. Reinhardt, Fang Yuan, Yijia Zhang, Peter Giannini, D. B. Marx, Dong Wang, Richard A. Reinhardt

Department of Statistics: Faculty Publications

Introduction: Juvenile idiopathic arthritis (JIA) often causes inflammation of the temporomandibular joint (TMJ) and has been treated with both systemic and intra-articular steroids, with concerns about effects on growing bones. In this study, we evaluated the impact of a macromolecular prodrug of dexamethasone (P-DEX) with inflammation-targeting potential applied systemically or directly to the TMJ.

Methods: Joint inflammation was initiated by injecting two doses of complete Freund’s adjuvant (CFA) at 1-month intervals into the right TMJs of 24 growing Sprague–Dawley male rats (controls on left side). Four additional rats were not manipulated. With the second CFA injection, animals received (1) 5 …

Threshold Models For Genome-Enabled Prediction Of Ordinal Categorical Traits In Plant Breeding, Osval A. Montesinos-López, Abelardo Montesinos-López, Paulino Pérez-Rodríguez, Gustavo De Los Campos, Kent M. Eskridge, José Crossa

Department of Statistics: Faculty Publications

Categorical scores for disease susceptibility or resistance often are recorded in plant breeding. The aim of this study was to introduce genomic models for analyzing ordinal characters and to assess the predictive ability of genomic predictions for ordered categorical phenotypes using a threshold model counterpart of the Genomic Best Linear Unbiased Predictor (i.e., TGBLUP). The threshold model was used to relate a hypothetical underlying scale to the outward categorical response. We present an empirical application where a total of nine models, five without interaction and four with genomic x environment interaction (G·E) and genomic additive x additive x environment interaction …

Measuring Peer Socialization For Adolescent Substance Use:A Comparison Of Perceived And Actual Friends’ Substance Use Effects, Arielle R. Deutsch, Pavel Chernyavskiy, Douglas Steinley, Wendy S. Slutske

Department of Statistics: Faculty Publications

Objective: There has been an increase in the use of social network analysis in studies of peer socialization effects on adolescent substance use. Some researchers argue that social network analyses provide more accurate measures of peer substance use, that the alternate strategy of assessing perceptions of friends’ drug use is biased, and that perceptions of peer use and actual peer use represent different constructs. However, there has been little research directly comparing the two effects, and little is known about the extent to which the measures differ in the magnitude of their influence on adolescent substance use, as well as …

A Copula Based Approach For Design Of Multivariate Random Forests For Drug Sensitivity Prediction, Saad Haider, Raziur Rahman, Souparno Ghosh, Ranadip Pal

Department of Statistics: Faculty Publications

Modeling sensitivity to drugs based on genetic characterizations is a significant challenge in the area of systems medicine. Ensemble based approaches such as Random Forests have been shown to perform well in both individual sensitivity prediction studies and team science based prediction challenges. However, Random Forests generate a deterministic predictive model for each drug based on the genetic characterization of the cell lines and ignores the relationship between different drug sensitivities during model generation. This application motivates the need for generation of multivariate ensemble learning techniques that can increase prediction accuracy and improve variable importance ranking by incorporating the relationships …