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Vibrational Spectroscopic Study Of The 1,3,5,7-Cyclooctatetraene At High Static Pressures, Edward Romano 2010 University of Nevada, Las Vegas

Vibrational Spectroscopic Study Of The 1,3,5,7-Cyclooctatetraene At High Static Pressures, Edward Romano

UNLV Theses, Dissertations, Professional Papers, and Capstones

1,3,5,7-cyclooctatetraene (COT) is a single-ringed hydrocarbon that has not been studied extensively under high static pressures. It was the intent of this study to reveal its high-pressure behavior through its vibrational spectra. To this end, its infrared spectra as a function of pressure were collected at the National Synchrotron Light Source (NSLS) U2A beamline, as well as its Raman spectra over pressure using a micro-Raman spectrometer.

The spectra show the typical stiffening of force constants with increasing pressure for most peaks, particularly those which would theoretically exhibit a mode-softening behavior under hypotheses of molecular planarization and aromatization ...


Patrilocal Exogamy As A Monitoring Mechanism: How Inheritance And Residence Patterns Co-Evolve, Brishti GUHA 2010 Singapore Management University

Patrilocal Exogamy As A Monitoring Mechanism: How Inheritance And Residence Patterns Co-Evolve, Brishti Guha

Research Collection School Of Economics

Economists have modeled inheritance norms assuming the pattern of post-marital residence is exogenous. We model the co-evolution of these two institutions, examining how patrilineal inheritance and patrilocal exogamy reinforced each other in a patrilineal-patrilocal equilibrium. We also derive conditions for a matrilineal-matrilocal equilibrium. The endogenous choice of the old to monitor the sexual behavior of the young women who reside with them, thereby affecting the paternity confidence of the young women’s husbands and hence their incentives, is crucial. Our model fits the data on the relationship between inheritance, residence patterns and paternity confidence, and on the importance of paternity ...


Seasonal Energy And Water Balance Of A Phragmites Australis-Dominated Wetland In The Republican River Basin (Southwestern Nebraska, Usa), Gregory J. Cutrell 2010 University of Nebraska - Lincoln

Seasonal Energy And Water Balance Of A Phragmites Australis-Dominated Wetland In The Republican River Basin (Southwestern Nebraska, Usa), Gregory J. Cutrell

Dissertations & Theses in Natural Resources

Climate and vegetation can dramatically alter the water cycle on local to regional scales. A change in the surface energy and water balance, especially in arid regions, can have significant impacts on local water availability and, therefore, water resource management. The purpose of this study is to understand the role of climate and vegetation in the energy and water balance of a riparian wetland in the central Great Plains. The site is located near the Republican River in southwestern Nebraska, where decreases in streamflow have been observed in recent decades. In an effort to reduce consumptive use from evapotranspiration (ET ...


Evaluating Hydroperiod Response In The Rainwater Basin Wetlands Of South-Central Nebraska, Richard D. Wilson 2010 University of Nebraska-Lincoln

Evaluating Hydroperiod Response In The Rainwater Basin Wetlands Of South-Central Nebraska, Richard D. Wilson

Dissertations & Theses in Natural Resources

A collection of wetlands in south-central Nebraska make up a region called the Rainwater Basin. This basin contains closed-basin wetlands formed in loess. The wetlands receive water from precipitation and irrigation runoff. Since the early 1900s, wetland area in the basin has decreased dramatically due to intensive agriculture which either altered or removed the wetlands. The Rainwater Basin wetlands provide many ecological services and thus, should be preserved, but are most noted for the resting, breeding, and feeding habitat they provide for millions of migratory birds that is not provided elsewhere in this region along the continental flyway.

Given the ...


A Bayesian Approach To Dose-Response Assessment And Drug-Drug Interaction Analysis: Application To In Vitro Studies, Violeta G. Hennessey 2010 University of Texas Graduate School of Biomedical Sciences at Houston

A Bayesian Approach To Dose-Response Assessment And Drug-Drug Interaction Analysis: Application To In Vitro Studies, Violeta G. Hennessey

UT GSBS Dissertations and Theses (Open Access)

The considerable search for synergistic agents in cancer research is motivated by the therapeutic benefits achieved by combining anti-cancer agents. Synergistic agents make it possible to reduce dosage while maintaining or enhancing a desired effect. Other favorable outcomes of synergistic agents include reduction in toxicity and minimizing or delaying drug resistance. Dose-response assessment and drug-drug interaction analysis play an important part in the drug discovery process, however analysis are often poorly done. This dissertation is an effort to notably improve dose-response assessment and drug-drug interaction analysis.

The most commonly used method in published analysis is the Median-Effect Principle/Combination Index ...


Dynamic Chemical Shift Imaging For Image-Guided Thermal Therapy, Brian A. Taylor 2010 University of Texas Graduate School of Biomedical Sciences at Houston

Dynamic Chemical Shift Imaging For Image-Guided Thermal Therapy, Brian A. Taylor

UT GSBS Dissertations and Theses (Open Access)

Magnetic resonance temperature imaging (MRTI) is recognized as a noninvasive means to provide temperature imaging for guidance in thermal therapies. The most common method of estimating temperature changes in the body using MR is by measuring the water proton resonant frequency (PRF) shift. Calculation of the complex phase difference (CPD) is the method of choice for measuring the PRF indirectly since it facilitates temperature mapping with high spatiotemporal resolution. Chemical shift imaging (CSI) techniques can provide the PRF directly with high sensitivity to temperature changes while minimizing artifacts commonly seen in CPD techniques. However, CSI techniques are currently limited by ...


An Implantable Mosfet Dosimeter Modified To Act As A Fiducial Marker, Joseph S. Dick 2010 University of Texas Graduate School of Biomedical Sciences at Houston

An Implantable Mosfet Dosimeter Modified To Act As A Fiducial Marker, Joseph S. Dick

UT GSBS Dissertations and Theses (Open Access)

In external beam radiation therapy, it is imperative that the prescribed dose is administered to the correct location and in the correct amount. Though several ex vivo methods of quality assurance are currently employed to achieve this goal, verifying that the correct dose is received within the patient in situ is impossible without the capability of measuring dose inside the patient. Recently, a method of measuring dose delivered within the patient has been developed, an implantable MOSFET dosimeter. This dosimeter is implanted within the patient and records the dose received. Since the dosimeter is implanted in the patient, it could ...


Characterization Of Optically Stimulated Luminescent Detectors In Photon & Proton Beams For Use In Anthropomorphic Phantoms, James R. Kerns 2010 University of Texas Graduate School of Biomedical Sciences at Houston

Characterization Of Optically Stimulated Luminescent Detectors In Photon & Proton Beams For Use In Anthropomorphic Phantoms, James R. Kerns

UT GSBS Dissertations and Theses (Open Access)

This study investigated characteristics of optically stimulated luminescent detectors (OSLDs) in protons, allowing comparison to thermoluminescent detectors, and to be implemented into the Radiological Physics Center’s (RPC) remote audit quality assurance program for protons, and for remote anthropomorphic phantom irradiations. The OSLDs used were aluminum oxide (Al2O3:C) nanoDots from Landauer, Inc. (Glenwood, Ill.) measuring 10x10x2 mm3. A square, 20(L)x20(W)x0.5(H) cm3 piece of solid water was fabricated with pockets to allow OSLDs and TLDs to be irradiated simultaneously and perpendicular to the beam. Irradiations were performed at 5cm depth in photons, and in ...


Thoracic Target Volume Delineation Using Various Maximum-Intensity Projection Computed Tomography Image Sets For Stereotactic Body Radiation Therapy, David A. Zamora 2010 University of Texas Graduate School of Biomedical Sciences at Houston

Thoracic Target Volume Delineation Using Various Maximum-Intensity Projection Computed Tomography Image Sets For Stereotactic Body Radiation Therapy, David A. Zamora

UT GSBS Dissertations and Theses (Open Access)

The motion of lung tumors during respiration makes the accurate delivery of radiation therapy to the thorax difficult because it increases the uncertainty of target position. The adoption of four-dimensional computed tomography (4D-CT) has allowed us to determine how a tumor moves with respiration for each individual patient. Using information acquired during a 4D-CT scan, we can define the target, visualize motion, and calculate dose during the planning phase of the radiotherapy process. One image data set that can be created from the 4D-CT acquisition is the maximum-intensity projection (MIP). The MIP can be used as a starting point to ...


Benchmarking And Implementation Of A New Independent Monte Carlo Dose Calculation Quality Assurance Audit Tool For Clinical Trials, Scott E. Davidson 2010 University of Texas Graduate School of Biomedical Sciences at Houston

Benchmarking And Implementation Of A New Independent Monte Carlo Dose Calculation Quality Assurance Audit Tool For Clinical Trials, Scott E. Davidson

UT GSBS Dissertations and Theses (Open Access)

Introduction Commercial treatment planning systems employ a variety of dose calculation algorithms to plan and predict the dose distributions a patient receives during external beam radiation therapy. Traditionally, the Radiological Physics Center has relied on measurements to assure that institutions participating in the National Cancer Institute sponsored clinical trials administer radiation in doses that are clinically comparable to those of other participating institutions. To complement the effort of the RPC, an independent dose calculation tool needs to be developed that will enable a generic method to determine patient dose distributions in three dimensions and to perform retrospective analysis of radiation ...


Evaluation Of Current And Alternative Spatial Patterns Of Grassland In The Loess Hills, Dustin A. Farnsworth, Lisa A. Schulte, Susanne Hickey 2010 Iowa State University

Evaluation Of Current And Alternative Spatial Patterns Of Grassland In The Loess Hills, Dustin A. Farnsworth, Lisa A. Schulte, Susanne Hickey

Natural Resource Ecology and Management Conference Papers, Posters and Presentations

Half of Iowa’s remnant prairie lies within the Loess Hills of western Iowa, yet development, woody encroachment, and agriculture continue to have an impact upon the size, shape, and quality of grasslands in the region. Given the limited resources available to manage grasslands, prioritizing restoration expenditures and targeting efforts to areas of greatest conservation potential are critical. To this end, we conducted an assessment of landscape patterns in the Loess Hills and developed a conservation priority index (CPI) to identify cropland with the greatest potential to promote connectivity of grasslands. Cropland parcels were given a CPI score between 1 ...


Noise Assumptions In Complex-Valued Sense Mr Image Reconstruction, Daniel B. Rowe, Iain P. Bruce 2010 Marquette University

Noise Assumptions In Complex-Valued Sense Mr Image Reconstruction, Daniel B. Rowe, Iain P. Bruce

Mathematics, Statistics and Computer Science Faculty Research and Publications

In fMRI, brain images are not measured instantaneously and a volume of images can take two seconds to acquire at a low 64x64 resolution. Significant effort has been put forth on many fronts to decrease image acquisition time including parallel imaging. In parallel imaging, sub-sampled spatial frequency points are measured in parallel and combined to form a single image. Measurement time is decreased at the expense of increased image reconstruction difficulty and time. One significant parallel imaging technique known as SENSE utilizes a complex-valued regression coefficient estimation process with transposes replaced by conjugate transposes. However, in SENSE the noise structure ...


Temporal And Spatial Assessment Of Evaporation, Transpiration, And Soil Moisture Redistribution, Brian M. Bird 2010 University of Nevada, Las Vegas

Temporal And Spatial Assessment Of Evaporation, Transpiration, And Soil Moisture Redistribution, Brian M. Bird

UNLV Theses, Dissertations, Professional Papers, and Capstones

At a native stand of creosote bush (Larrea tridentata) in North Las Vegas, a rainfall simulation study was conducted over a 12 month period from October 2005 to October 2006. Simulated rainfall occurred during the winter, spring, summer, and fall periods. Rainfall simulation systems were positioned on each of 12 plots, each containing a single creosote bush. Simulated rainfall events occurred at night with multiple short pulses designed to maximize infiltration while minimizing ponding. Yearly simulated rainfall amounts were set at 0, 15, 30 and 60 cm (replicated three times) and were approximately 0, 1.5, 3.0 and 6 ...


Cloud Storage And Online Bin Packing, Swathi Venigella 2010 University of Nevada, Las Vegas

Cloud Storage And Online Bin Packing, Swathi Venigella

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cloud storage is the service provided by some corporations (such as Mozy and Carbonite) to store and backup computer files. We study the problem of allocating memory of servers in a data center based on online requests for storage. Over-the-net data backup has become increasingly easy and cheap due to cloud storage. Given an online sequence of storage requests and a cost associated with serving the request by allocating space on a certain server one seeks to select the minimum number of servers as to minimize total cost. We use two different algorithms and propose a third algorithm; we show ...


Evaluating The Impacts Of Water Conservation Policies On Water Demand, Availability And Outdoor Water Use In The Las Vegas Valley, Kamal Qaiser 2010 University of Nevada, Las Vegas

Evaluating The Impacts Of Water Conservation Policies On Water Demand, Availability And Outdoor Water Use In The Las Vegas Valley, Kamal Qaiser

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Valley, located in the arid Southern Nevada region, with a growing population, limited water resources, and a prolonged drought, faces a challenge in meeting its future water needs. Southern Nevada Water Authority (SNWA), the main water management agency in the Valley, is focusing on water conservation to reduce water demand. Current water use is 945 lpcd (250 gpcd) which SNWA aims to reduce to 752 lpcd (199 gpcd) by 2035. Presently the indoor outdoor water use proportion is about 40:60 in the Valley. An important component of the Valley's supply are the return flow credits ...


Clay Mineral Cycles Identified By Diffuse Spectral Reflectance In Quaternary Sediments From The Northwind Ridge: Implications For Glacial-Interglacial Sedimentation Patterns In The Arctic Ocean, Lyanne N. Yurco, Joseph D. Ortiz, Leonid Polyak, Dennis A. Darby, Kevin A. Crawford 2010 Old Dominion University

Clay Mineral Cycles Identified By Diffuse Spectral Reflectance In Quaternary Sediments From The Northwind Ridge: Implications For Glacial-Interglacial Sedimentation Patterns In The Arctic Ocean, Lyanne N. Yurco, Joseph D. Ortiz, Leonid Polyak, Dennis A. Darby, Kevin A. Crawford

OEAS Faculty Publications

A Quaternary record of fine-grained sediment composition is used to investigate Arctic Ocean climate variability on glacial-interglacial time scales. Diffuse spectral reflectance data from sediment core P1-92AR-P25 from the Northwind Ridge, north of Alaska, demonstrates cyclic variations in mineralogy. Varimax-rotated R-mode factor analysis of down-core data revealed three major mineralogical assemblages, which were then compared with the content of manganese, a proxy for basin ventilation, and thus glacial-interglacial cycles. Results indicate that factor 1, a smectite + chlorite clay assemblage, was delivered to the core site during interglacials, either by fluvial discharge or sea-ice drift from Siberian rivers or inflow from ...


Reconstruction And Analysis Of The Chukchi Sea Circulation In 1990-1991, Gleb Panteleev, Dmitri A. Nechaev, Andrey Proshutinsky, R. Woodgate, J. Zhang 2010 University of Alaska

Reconstruction And Analysis Of The Chukchi Sea Circulation In 1990-1991, Gleb Panteleev, Dmitri A. Nechaev, Andrey Proshutinsky, R. Woodgate, J. Zhang

Faculty Publications

The Chukchi Sea (CS) circulation reconstructed for September 1990 to October 1991 from sea ice and ocean data is presented and analyzed. The core of the observational data used in this study comprises the records from 12 moorings deployed in 1990 and 1991 in U. S. and Russian waters and two hydrographic surveys conducted in the region in the fall of 1990 and 1991. The observations are processed by a two-step data assimilation procedure involving the Pan-Arctic Ice-Ocean Modeling and Assimilation System (employing a nudging algorithm for sea ice data assimilation) and the Semi-implicit Ocean Model [utilizing a conventional four-dimensional ...


Protecting Privacy And Ensuring Security Of Rfid Systems Using Private Authentication Protocols, Md. Endadul Hoque 2010 Marquette University

Protecting Privacy And Ensuring Security Of Rfid Systems Using Private Authentication Protocols, Md. Endadul Hoque

Master's Theses (2009 -)

Radio Frequency IDentification (RFID) systems have been studied as an emerging technology for automatic identification of objects and assets in various applications ranging from inventory tracking to point of sale applications and from healthcare applications to e-passport. The expansion of RFID technology, however, gives rise to severe security and privacy concerns. To ensure the widespread deployment of this technology, the security and privacy threats must be addressed. However, providing solutions to the security and privacy threats has been a challenge due to extremely inadequate resources of typical RFID tags. Authentication protocols can be a possible solution to secure RFID communications ...


Investigation Of Potential Pathways And Multi-Cycle Bioregeneration Of Ion-Exchange Resin Laden With Perchlorate, Mohamadali Sharbatmaleki 2010 University of Nevada, Las Vegas

Investigation Of Potential Pathways And Multi-Cycle Bioregeneration Of Ion-Exchange Resin Laden With Perchlorate, Mohamadali Sharbatmaleki

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ion-exchange (IX) is possibly the most feasible technology for perchlorate removal and perchlorate-selective and non-selective IX resins are commercially available for this purpose. The use of both resins has shortcomings. Selective resins are incinerated after one time use, and non-selective resins produce a regenerant waste stream that contains high concentration of perchlorate. A process involving directly contacting of spent IX resin containing perchlorate with perchlorate-reducing bacteria (PRB) to bioregenerate the resin has been developed and proven recently. In this process PRB biodegrade perchlorate ions which are attached to the functional groups of the resin.

Although its feasibility has been proven ...


The Effects Of Contact Metamorphism On The Host Rocks For Carlin-Type Mineralization At The Getchell Development, Nevada, Usa, Nathan C. Eck 2010 University of Nevada, Las Vegas

The Effects Of Contact Metamorphism On The Host Rocks For Carlin-Type Mineralization At The Getchell Development, Nevada, Usa, Nathan C. Eck

UNLV Theses, Dissertations, Professional Papers, and Capstones

Carlin-type gold deposits (CTGDs) result from low to moderate temperature hydrothermal systems which form replacement bodies in carbonate or calcareous host rocks. The Getchell CTGD is located on the Getchell trend in north central Nevada. The Eocene age mineralization is locally hosted within the metamorphic aureole of the Cretaceous age Osgood stock. Previous studies have noted that the effects of the contact metamorphism can be heterogeneous, with strongly calc-silicate altered carbonates transitioning to relatively pristine limestone over short distances. The main finding of this study was that the variability in calc-silicate alteration is largely dependent on the differing host lithologies ...


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