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Heritable Choice Of Colony Size In Cliff Swallows: Does Experience Trump Genetics In Older Birds?, Erin A. Roche, Charles R. Brown, Mary Bomberger Brown 2011 University of Tulsa

Heritable Choice Of Colony Size In Cliff Swallows: Does Experience Trump Genetics In Older Birds?, Erin A. Roche, Charles R. Brown, Mary Bomberger Brown

Papers in Natural Resources

The variation in breeding colony size seen in populations of most colonial birds may reflect heritable choices made by individuals that are phenotypically specialized for particular social environments. Although a few studies have reported evidence for genetically based choice of group sizes in birds, we know relatively little about the extent to which animals potentially rely on experience versus innate preferences in deciding how many conspecifics to settle with at different times of their lives. We conducted a cross-fostering experiment in 1997–1998 on cliff swallows, Petrochelidon pyrrhonota, in southwestern Nebraska, USA, in which some individuals were reared in colonies ...


Climatic Controls On The Summertime Energy Balance Of A Thermokarst Lake In Northern Alaska: Short-Term, Seasonal, And Interannual Variability, Brittany L. Potter 2011 University of Nebraska-Lincoln

Climatic Controls On The Summertime Energy Balance Of A Thermokarst Lake In Northern Alaska: Short-Term, Seasonal, And Interannual Variability, Brittany L. Potter

Dissertations & Theses in Natural Resources

Shallow, thermokarst lakes that develop atop permafrost are a prominent landscape feature on the Arctic Coastal Plain (ACP) of northern Alaska. The ACP is vulnerable to ongoing climate change and landscape modification, as thousands of thaw lakes and ponds are impacted by changes in temperature, precipitation, thawing permafrost, and human activity. Although summer in the Arctic is short, incoming solar radiation and lake evaporation are relatively high, and both factors play a significant role in the landscape water balance. Furthermore, lake evaporation is anticipated to increase as the ice-free season lengthens and water temperatures become warmer. To improve our understanding ...


Climate Change And Climate Variability: El Salvador – Impacts On Productivity Of Grain Crops And Opportunities For Management And Improvement, P. V. Vara Prasad 2011 Kansas State University

Climate Change And Climate Variability: El Salvador – Impacts On Productivity Of Grain Crops And Opportunities For Management And Improvement, P. V. Vara Prasad

INTSORMIL Presentations

1. Climate change and climate variability (past and future).

2. Climate change and variability in El Salvador (climate models).

3. Impact of temperature on grain yield of dry bean, maize and sorghum in El Salvador (crop simulation models).

4. Effects of temperature, drought and/or carbon dioxide: experimental evidence (response of grain sorghum, maize and dry bean).

5. Opportunities for crop management and genetic improvement.


An Extension Of The Rishon Model, Paul Finkler 2011 University of Nebraska-Lincoln

An Extension Of The Rishon Model, Paul Finkler

Paul Finkler Papers

We present an extension of the Rishon Model of Harari, et. al. [1] [2] [3] In that model, the first generation leptons and quarks are each made from three rishons of two varieties, T and V as follows: ve = V V V , e+ = T T T , d = T V V , and u = T T V . In addition to the original rishons and their anti-rishons T and V , we introduce the dark rishon X and its anti-rishon X; all have spin 1/2.

An exciting possibility that emerges from this idea is the possiblity of ‘beams’ of dark matter coming ...


First-Principles Studies On Physical And Chemical Properties Of Nanostructures, Menghao Wu 2011 University of Nebraska-Lincoln

First-Principles Studies On Physical And Chemical Properties Of Nanostructures, Menghao Wu

Theses, Dissertations, and Student Research: Department of Physics and Astronomy

The physical and chemical properties of decorated graphene and graphene ribbons, single-layer III-V systems, three-dimensional carbon and BN foam, and transition-metal-molecular sandwich nanowires have been investigated by first-principle calculations and their potential applications have been predicted. First, it is shown that zigzag graphene nanoribbons (ZGNRs) can be converted into half metal when their edges are decorated by some chemical functional groups, and the half-metalicity is induced by chemical potential difference between two edges when one edge is decorated by electron-donating group like –OH and the other edge is decorated by electron-accepting group like –F, -NH2, -N(CH3)2 ...


Precisely Serializable Snapshot Isolation, Stephen Anthony Revilak 2011 University of Massachusetts Boston

Precisely Serializable Snapshot Isolation, Stephen Anthony Revilak

Graduate Doctoral Dissertations

Snapshot Isolation (SI) is a method of database concurrency control that uses timestamps and multiversioning, in preference to pessimistic locking. Since its introduction in 1995, SI has become a popular isolation level, and has been implemented in a variety of database systems: Oracle, Postgres, Microsoft SQL Server, and others. Despite the benefits that SI offers, one of the things it cannot provide is serializability. Past approaches for serializable SI have focused on avoiding dangerous structures (or essential dangerous structures). Dangerous structures are patterns of transaction dependencies that indicate the potential for a non-serializable execution; however, the presence of dangerous structures ...


Making An Impact On The Obesity Epidemic By Deploying A Mobile Fitness Suite On The Android Market, Chad Richards 2011 University of Arkansas, Fayetteville

Making An Impact On The Obesity Epidemic By Deploying A Mobile Fitness Suite On The Android Market, Chad Richards

Computer Science and Computer Engineering Undergraduate Honors Theses

The Mobile Fitness Suite aims to make an impact on the obesity epidemic by deploying a set of mobile fitness applications on the Android Market. The thesis details the health and financial issues with the obesity epidemic, along with its causes, and how a set of fitness applications can aid with the obesity epidemic. It also explains the reasons for releasing the program on the Android Market and details each step in the process of deploying a mobile application to the Android Market. Further, it discusses the design and architecture that went into the development of the Mobile Fitness Suite ...


Webtailor: Internet Service For Salient And Automatic User Interest Profiles, John Anderson 2011 University of Arkansas, Fayetteville

Webtailor: Internet Service For Salient And Automatic User Interest Profiles, John Anderson

Computer Science and Computer Engineering Undergraduate Honors Theses

Website personalization systems seek to give users unique, tailored content and experiences on the Internet. A key feature of these systems is a user profile that represents each user in a way that distinguishes them from others. In current personalization systems, the data used to create these profiles is extremely limited, which leads to a host of problems and ineffectual personalization. The main goal of this thesis is to improve these personalization systems by addressing their lack of data and its poor quality, breadth, and depth. This is accomplished by analyzing and classifying the content of each user's Internet ...


Analysis Of 26Al + P Elastic And Inelastic Scattering Reactions And Galactic Abundances Of 26Al, Stephen Todd Pittman 2011 University of Tennessee, Knoxville

Analysis Of 26Al + P Elastic And Inelastic Scattering Reactions And Galactic Abundances Of 26Al, Stephen Todd Pittman

Doctoral Dissertations

26Al(p,p)26Al and 26Al(p,p’)26Al* scattering reactions were performed at the Holifield Radioactive Ion Beam Facility (HRIBF) at the Oak Ridge National Laboratory (ORNL). The purpose of the elastic scattering study was to determine properties of previously uncharacterized 27Si levels above the proton threshold in the energy range E(c.m.) ~ 0.5 - 1.5 MeV and to calculate reaction rates for the 26Al(p,γ[gamma])27Si reaction that destroys 26Al. The inelastic scattering reaction was also evaluated to investigate the reaction that produces the metastable state ...


The Design, Synthesis And Application Of A Novel Class Of N-Heterocyclic Carbene Catalysts, Abigail Lynn Hubbard 2011 University of Arkansas, Fayetteville

The Design, Synthesis And Application Of A Novel Class Of N-Heterocyclic Carbene Catalysts, Abigail Lynn Hubbard

Theses and Dissertations

A copper carbenoid representative of a novel class of N-heterocyclic carbene (NHC) catalysts has been synthesized. This compound was characterized by X-ray crystallography and was found to confirm the rationale of our synthetic design: The C2-symmetric structure places four stereocenters in close proximity (<5Å) to the reactive site of the carbene via a trans-annular gearing effect. The copper carbenoid was found to catalyze the hydrosilylation of prochiral ketones with superb selectivity in high yield.


Defining, Executing And Visualizing Representative Workflows In A Retail Domain, May Zeineldin 2011 University of Arkansas, Fayetteville

Defining, Executing And Visualizing Representative Workflows In A Retail Domain, May Zeineldin

Theses and Dissertations

Our lives are filled with routine activities that we do more or less on auto-pilot such as driving to work and cooking. This thesis explores a workflow representation as a way to represent such activities of daily living. The domain of a retail store environment is used. Workflows are initially expressed in a structured English representation, then translated into a Petri net notation and implemented in mix of Petri nets, Lua, and C so that the resulting workflows can be displayed as the actions of collections of avatarbots (avatars controlled by programs) in a 3D virtual world, Second Life. One ...


The Beta Decay Of 79,80,81zn And Nuclear Structure Around The N=50 Shell Closure, Stephen William Padgett 2011 University of Tennessee, Knoxville

The Beta Decay Of 79,80,81zn And Nuclear Structure Around The N=50 Shell Closure, Stephen William Padgett

Doctoral Dissertations

This dissertation reports on new information in the [beta minus] decay of the neutron-rich nucleus 81Zn, which populates states in its daughter nucleus 81Ga. This includes new [gamma]-ray transitions in the daughter nucleus, 81Ga, as well as a [beta]-delayed neutron branching ratio. This isotope was produced at the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory through the Isotope Separation Online technique. They are fission fragments from proton-induced fission on a uranium carbide target. These fission fragments are ionized and both mass and isotopically separated before arriving at the Low Energy Radioactive Ion Beam Spectroscopy Station ...


An Investigation Of Pinning Landscapes With Engineered Defects: Contact-Free Critical Current Density Measurements, John William Sinclair 2011 University of Tennessee, Knoxville

An Investigation Of Pinning Landscapes With Engineered Defects: Contact-Free Critical Current Density Measurements, John William Sinclair

Doctoral Dissertations

Pinning landscapes in modern second generation coated conductors are excellent candidates for studies of vortex pinning. The ability to produce engineered defects in thin films of high temperature superconductors allows one to investigate representative distinct pinning sites, with the objective of understanding how different pinning centers contribute, compete and evolve under varying conditions of magnetic field strength and orientation, and temperature.New contact-free methods were developed specifically to investigate this system in new ways, especially the dependence of the critical current density Jc on orientation of the magnetic field. A superconducting quantum interference device (SQUID)-based magnetometer was used to ...


Rupert On-Time Food Dispenser, Eric Smith, Darik Boutsaboualoy 2011 Indiana University - Purdue University Fort Wayne

Rupert On-Time Food Dispenser, Eric Smith, Darik Boutsaboualoy

Computer and Electrical Engineering Technology & Information Systems and Technology Senior Design Projects

No abstract provided.


Object Recognition Based On Shape And Function, Akihiro Eguchi 2011 University of Arkansas, Fayetteville

Object Recognition Based On Shape And Function, Akihiro Eguchi

Computer Science and Computer Engineering Undergraduate Honors Theses

This thesis explores a new approach to computational object recognition by borrowing an idea from child language acquisition studies in developmental psychology. Whereas previous image recognition research used shape to recognize and label a target object, the model proposed in this thesis also uses the function of the object resulting in a more accurate recognition. This thesis makes use of new gaming technology, Microsoft’s Kinect, in implementing the proposed new object recognition model. A demonstration of the model developed in this project properly infers different names for similarly shaped objects and the same name for differently shaped objects.


Powersearch: Augmenting Mobile Phone Search Through Personalization, Xiangyu Liu 2011 University of Arkansas, Fayetteville

Powersearch: Augmenting Mobile Phone Search Through Personalization, Xiangyu Liu

Computer Science and Computer Engineering Undergraduate Honors Theses

Cell phone has become a fundamental element of people's life. People use it to call each other, browse websites, send text messages, etc. Among all the functionalities, the most important and frequently used is the search functionality. Based on ComScore, in July 2008, Google was estimated to host 235 millions searches per day. However, unlike the search on desktop, the search on cell phone has one critical constrain: battery. Cell phone performing a normal Google search, the battery drains very fast. The reason is that when sending a query to and fetching the results from Google, cell phone keeps ...


An Analysis Of Breast Cancer Metastasis, Jennifer Lee Gildner 2011 California Polytechnic State University - San Luis Obispo

An Analysis Of Breast Cancer Metastasis, Jennifer Lee Gildner

Statistics

The main objective of this paper is to evaluate possible socio-economic status, clinical, and treatment associations with the occurrence of distant metastasis in Stage I – III breast cancer patients. After analysis in a logistic regression model, four variables were found to be significant with occurrence of distant metastases. These variables were: education, disease group (Triple-negative, Her2Neu-positive and Luminal A), stage at diagnosis, and concordance to chemotherapy based on the NCCN guidelines. Patients without a college degree were found to be more likely to develop distant metastasis than those with a college degree (OR = 2.46 95% CI 1.44 – 4 ...


Cytongrasp: Cyton Alpha Controller Via Graspit! Simulation, Nicholas Wayne Overfield 2011 University of Tennessee, Knoxville

Cytongrasp: Cyton Alpha Controller Via Graspit! Simulation, Nicholas Wayne Overfield

Masters Theses

This thesis addresses an expansion of the control programs for the Cyton Alpha 7D 1G arm. The original control system made use of configurable software which exploited the arm’s seven degrees of freedom and kinematic redundancy to control the arm based on desired behaviors that were configured off-line. The inclusions of the GraspIt! grasp planning simulator and toolkit enables the Cyton Alpha to be used in more proactive on-line grasping problems, as well as, presenting many additional tools for on-line learning applications. In short, GraspIt! expands what is possible with the Cyton Alpha to include many machine learning tools ...


Field-Based Constraints On The Origin Of The Benton Uplift, Ouachita Mountains, Rachel Victoria Keng 2011 University of Arkansas, Fayetteville

Field-Based Constraints On The Origin Of The Benton Uplift, Ouachita Mountains, Rachel Victoria Keng

Theses and Dissertations

The Ouachita Mountains are an east-west trending fold-and-thrust belt exposed in west central Arkansas and southeastern Oklahoma. The Mississippian-Pennsylvanian Ouachita orogeny occurred when the Sabine arc terrane collided during south-facing subduction, during closure of the Cambrian passive margin of the North American plate. Deep-water Paleozoic strata were incorporated into an accretionary wedge as the Sabine terrane approached the North American plate. Folds and thrust faults in the Ouachita Mountains generally verge north due to tectonic transport of an accretionary wedge from south to north. Structures in the Benton and Broken Bow Uplifts (located in the core of the wedge) locally ...


Algebraic Properties Of Killing Vectors For Lorentz Metrics In Four Dimensions, Jesse W. Hicks 2011 Utah State University

Algebraic Properties Of Killing Vectors For Lorentz Metrics In Four Dimensions, Jesse W. Hicks

All Graduate Plan B and other Reports

Four-dimensional space-times with symmetry play a central role in the theory of general relativity. In 1961, in the book Einstein Spaces, A.Z. Petrov gave a complete local classification of four-dimensional space-times based upon their local isometry group, that is, their Lie algebra of Killing vector fields. In this report we discuss algebraic and geometric properties of these Lie algebras. A database of these properties has been computed for the five-dimensional Lie algebras of Killing vectors found in Petrov. As an application of our work, we present dieomorphisms between a few pairs of these Lie algebras of Killing vectors.


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