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A 018μm Cmos Transmitter for Ecg Signals (open access)

A 018μm Cmos Transmitter for Ecg Signals

Electrocardiography (ECG) signal transmitter is the device used to transmit the electrical signals of the heart to the remote machine. These electrical signals are ECG signals caused due to electrical activities in the heart. ECG signals have very low amplitude and frequency; hence amplification of the signals is needed to strengthen the signal. Conversion of the amplified signal into digital information and transmitting that information without losing any data is the key. This information is further used in monitoring the heart.
Date: December 2013
Creator: Kakarna, Tejaswi
Object Type: Thesis or Dissertation
System: The UNT Digital Library
3GPP Long Term Evolution LTE Scheduling (open access)

3GPP Long Term Evolution LTE Scheduling

Future generation cellular networks are expected to deliver an omnipresent broadband access network for an endlessly increasing number of subscribers. Long term Evolution (LTE) represents a significant milestone towards wireless networks known as 4G cellular networks. A key feature of LTE is the implementation of enhanced Radio Resource Management (RRM) mechanism to improve the system performance. The structure of LTE networks was simplified by diminishing the number of the nodes of the core network. Also, the design of the radio protocol architecture is quite unique. In order to achieve high data rate in LTE, 3rd Generation Partnership Project (3GPP) has selected Orthogonal Frequency Division Multiplexing (OFDM) as an appropriate scheme in terms of downlinks. However, the proper scheme for an uplink is the Single-Carrier Frequency Domain Multiple Access due to the peak-to-average-power-ratio (PAPR) constraint. LTE packet scheduling plays a primary role as part of RRM to improve the system’s data rate as well as supporting various QoS requirements of mobile services. The major function of the LTE packet scheduler is to assign Physical Resource Blocks (PRBs) to mobile User Equipment (UE). In our work, we formed a proposed packet scheduler algorithm. The proposed scheduler algorithm acts based on the number …
Date: December 2013
Creator: Alotaibi, Sultan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation (open access)

Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation

In this work we address two problems in computational chemistry relevant to biomolecular modeling. In the first project, we consider the conformer space of melatonin as a a representative example of “real-life” flexible biomolecules. Geometries for all 52 unique conformers are optimized using spin-component scaled MP2, and then relative energies are obtained at the CCSD (T) level near the complete basis set limit. These are then used to validate a variety of DFT methods with and without empirical dispersion corrections, as well as some lower-level ab initio methods. Basis set convergence is found to be relatively slow due to internal C-H…O and C-H…N contacts. Absent dispersion corrections, many DFT functionals will transpose the two lowest conformers. Dispersion corrections resolve the problem for most functionals. Double hybrids yield particularly good performance, as does MP2.5. In the second project, we propose a simple DFT-based diagnostic for nondynamical correlation effects. Aλ= (1-TAE [ΧλC]/TAE[XC])/λ where TAE is the total atomization energy, XC the “pure” DFT exchange-correlation functional, and ΧλC the corresponding hybrid with 100λ% HF-type exchange. The diagnostic is a good predictor for sensitivity of energetics to the level of theory, unlike most of the wavefunction-based diagnostics. For GGA functionals, Aλ values approaching unity …
Date: August 2013
Creator: Fogueri, Uma
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Ability of Offenders with Psychopathic Traits to Simulate Cognitive and Affective Empathy (open access)

Ability of Offenders with Psychopathic Traits to Simulate Cognitive and Affective Empathy

The accurate assessment of psychopathy constitutes a critical component of forensic assessments addressing offender populations. Among the core characteristics of psychopathy, the interpersonal component of deception and empathic deficits are prominently observed in offenders with psychopathic traits. Given the negative consequences of being classified as a psychopath, offenders may be likely to minimize their psychopathic traits. In particular, no research has investigated whether offenders with psychopathic traits are able to simulate empathy in an effort to mask their cognitive or affective empathy deficits (e.g., lack of remorse about offenses). The present study aims to contribute to the literature with regard to the simulation of empathy. Using a mixed between- and within-subjects design, 81 male detainees were placed into (a) a low psychopathy group, (b) a moderate psychopathy group, or (c) a high psychopathy group based on the Psychopathy Checklist – Revised. For the within-subjects component, all offenders answered empathy questionnaires under genuine and simulation conditions. Results indicate the sample possessed cognitive empathy, but did not display affective empathy under genuine instructions. Under simulation instructions, participants significantly increased their scores on several empathy measures. The implications of simulated empathy and comparisons between groups regarding simulation abilities are discussed.
Date: August 2013
Creator: Robinson, Emily V.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Acculturation and Feminist Endorsement on Control of Health and Health Behaviors in Hispanic Females (open access)

Acculturation and Feminist Endorsement on Control of Health and Health Behaviors in Hispanic Females

Hispanic women are the fastest growing population in the United States. Thus, it is important to explore health disparities that affect this population and better understand potential causes. Several explanations have been proposed for disparities that exist including turning to cultural alternatives rather than conventional medicine, low numbers of health insurance enrollments among Hispanics, and acculturation. However, little attention has been given to explanations that take into account the unique experiences of Hispanic women. The present study explored these experiences through investigation of endorsement of feminist attitudes (e.g., gender role adherence and beliefs that men and women should be treated equally in society) and level of acculturation. Undergraduate Hispanic women (18-24 years of age, M = 20.25, SD = 1.51) at the University of North Texas completed measures including the Multidimensional Health Questionnaire, the Acculturation Rating Scale for Mexican Americans-II, and the Liberal Feminist Attitude and Ideology Scale. Although results indicate that acculturation was not significant in the sample, feminist endorsement was found to be positively correlated with health-esteem, health-efficacy, and internal-health locus of control. Limitations and recommended directions for future research are explored.
Date: August 2013
Creator: Garner, Ashley Nicole
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Acute Hormonal Response to the Kettlebell Swing Exercise (open access)

The Acute Hormonal Response to the Kettlebell Swing Exercise

The purpose of this investigation was to examine the acute hormonal response to a bout of kettlebell swing exercise. Ten healthy men (19-30 y, 23.6 ± 3.5 y, 174.6 ± 5.7 cm, 78.7 ± 9.9 kg) who were engaged in resistance training at least twice per week but were inexperienced with kettlebell swings participated in this study. Participants were familiarized with the kettlebell swing exercise during an initial visit. During the subsequent experimental protocol visit, participants performed 12 rounds of 30 seconds of 16-kg kettlebell swings alternated with 30 seconds of rest. Heart rate (HR) and rating of perceived exertion (RPE) were measured at the end of every round of swings. Fasted blood samples were collected pre-exercise (PRE), immediately post (IP), 15 minutes post (P15), and 30 minutes post exercise (P30) and analyzed for total testosterone (T), growth hormone (GH), cortisol, and lactate concentrations. Participants completed a total of 227 ± 23 swings (average swings per round: 19 ± 2). HR and RPE increased significantly (P < 0.05) throughout the exercise protocol. Lactate concentrations were significantly increased at all post exercise time points compared to PRE. T was significantly increased at IP compared to PRE. GH was significantly increased at …
Date: December 2013
Creator: Budnar, Ronald Gene, Jr.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Adapting on the Plains: the United States Army's Evolution of Mobile Warfare in Texas, 1848-1859 (open access)

Adapting on the Plains: the United States Army's Evolution of Mobile Warfare in Texas, 1848-1859

The Army, despite having been vexed for a century on how to effectively fight the Plains Indians, ultimately defeated them only a decade after the Civil War. This thesis will bring to the forefront those individuals who adapted fighting techniques and ultimately achieved victories on the Texas frontier before the Civil War. The majority of these victories came as a result of mounted warfare under the direction of lower ranking officers in control of smaller forces. The tactic of fighting Indians from horseback was shown to be effective by the Rangers and later emulated by the Army.
Date: May 2013
Creator: Buchy, Mark B.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
An Age-based Etic Analysis of Orthographic Variation in Computer-mediated French Discourse (open access)

An Age-based Etic Analysis of Orthographic Variation in Computer-mediated French Discourse

This study examines orthographic variation in synchronous computer-mediated French discourse. All nontraditional variations of selected frequently occuring items are quantified in order to provide an etic (i.e., from an external perspective) analysis. The primary variable of interest is age since this study focuses on providing a comparison of chat participants in their twenties versus those in their fifties. The widespread claim is that younger people communicate using more informal and/or nontraditional forms than older people; however, the results of the present study suggest that this is not always the case. The main finding of the present study is that the twentysomethings and the fiftysomethings produce the nontraditional orthography in a similar fashion in 52.2% of the terms, and in a non-similar fashion in 47.8% of the terms. Following the presentation and discussion of the results, directions for future research are provided.
Date: December 2013
Creator: Kharrat, Laila Kiblawi
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Alchemies (open access)

Alchemies

This thesis consists of a collection of poems and a critical preface. The preface is a discussion of Elizabeth Bishop's descriptive mode, as demonstrated by three of her poems: "Sandpiper," "The Monument," and "Santarém." I argue for Bishop's descriptions as creative acts, and examine the gestures that help her make the reader aware of the shaping power she exercises.
Date: August 2013
Creator: Heffner, Christopher Daniel
Object Type: Thesis or Dissertation
System: The UNT Digital Library
An Analysis of the Value-altering Effect of Motivating Operations (open access)

An Analysis of the Value-altering Effect of Motivating Operations

Motivating operations (MOs) may affect behavior in two ways; A) an MO momentarily alters the frequency of behavior for which a particular consequence has served as reinforcement (evocative-effect) and B) an MO momentarily alters the behavioral effects of the relevant consequence (value-altering effect). Many studies have empirically demonstrated the evocative function of MOs, however, few if any studies have attempted to systematically manipulate and measure the value-altering effect. The focus of this study was to investigate the value-altering effect by measuring choice and response allocation across two alternative tasks. Participants were two female girls diagnosed with autism. During conditioning sessions, experimenters created a history for the children in which clicking on a moving square on a computer monitor produced a small piece of edible. Prior to some conditions, the participants were allowed 5 min of free-access to the edibles, and in other sessions, access to edibles prior to session was restricted. During these sessions, the square was either red or blue depending on the condition type (pre-access or restricted-access). During probe sessions, both colored squares were concurrently available and participants were allowed to allocate their responding to whichever square they chose. One participant preferred the square associated with restricted-access, which …
Date: August 2013
Creator: Devine, Bailey
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Analytical Model of Cold-formed Steel Framed Shear Wall with Steel Sheet and Wood-based Sheathing (open access)

Analytical Model of Cold-formed Steel Framed Shear Wall with Steel Sheet and Wood-based Sheathing

The cold-formed steel framed shear walls with steel sheets and wood-based sheathing are both code approved lateral force resisting system in light-framed construction. In the United States, the current design approach for cold-formed steel shear walls is capacity-based and developed from full-scale tests. The available design provisions provide nominal shear strength for only limited wall configurations. This research focused on the development of analytical models of cold-formed steel framed shear walls with steel sheet and wood-based sheathing to predict the nominal shear strength of the walls at their ultimate capacity level. Effective strip model was developed to predict the nominal shear strength of cold-formed steel framed steel sheet shear walls. The proposed design approach is based on a tension field action of the sheathing, shear capacity of sheathing-to-framing fastener connections, fastener spacing, wall aspect ratio, and material properties. A total of 142 full scale test data was used to verify the proposed design method and the supporting design equations. The proposed design approach shows consistent agreement with the test results and the AISI published nominal strength values. Simplified nominal strength model was developed to predict the nominal shear strength of cold-formed steel framed wood-based panel shear walls. The nominal shear …
Date: May 2013
Creator: Yanagi, Noritsugu
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Arvo Pärt and Three Types of His Tintinnabuli Technique (open access)

Arvo Pärt and Three Types of His Tintinnabuli Technique

Arvo Pärt, an Estonian composer, was born in 1935. Most of the works at the beginning of his career were for piano in the neo-classical style. After that, he turned his interest to serial music and continued creating works with serial techniques throughout the 1960s. After his "self-imposed silence" period (during the years 1968-1976), Pärt emerged with a new musical style, which he called tintinnabuli. Although, this technique was influenced by music from the medieval period, the texture and function of its musical style cannot be described easily in terms of any single musical technique of the past. This study explores the evolution of Arvo Pärt's tintinnabuli technique in its first decade 1976-1985, which is divided into three different types. It provides musical examples from the scores of selected works, Für Alina, Cantus in Memory of Benjamin Britten, Cantate Domino canticum novum, Missa Sillabica, Stabat Mater and Es sang vor langen Jahren, and their analyses with supporting interpretative sketches. The goal of this thesis is to provide the reader a basis for understanding and recognizing the different types of Pärt's tintinnabuli technique.
Date: May 2013
Creator: Kongwattananon, Oranit
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Assessing the Role of Smaller Format Retailers on the Food Desert Landscape in Dallas, Texas (open access)

Assessing the Role of Smaller Format Retailers on the Food Desert Landscape in Dallas, Texas

Many policy and business decisions regarding food deserts in the U.S. are based on the United States Department of Agriculture (USDA) definition of a food desert. This definition only includes large/national chain grocery retailers, based on the assumption that these major retailers are the only affordable sources of food contributing to balanced diets. As alternative distribution channels, including smaller stores, start to include groceries in their product offering, the need to consider the role of other businesses in the food retailing environment should be addressed. This thesis assesses the role of smaller format grocery retailers (small local grocers, convenience stores, gas stations, dollar stores, and drug stores) in shaping the food desert landscape in Dallas, Texas. The analysis evaluates the products offered in these stores, and then identifies the difference these stores make when included in the USDA analysis. This was done by collecting in-store data to determine the variety of products offered, the affordability of those products, and the overall healthfulness of the store. In addition, the gaps in supply and demand were identified in the USDA-defined food deserts in order to identify the impact any smaller format retailer may have. The findings suggest that, overall, smaller format retailers …
Date: May 2013
Creator: Regan, Amanda D.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Attention Biases Associated with Vulnerability to Bipolar Disorder (open access)

Attention Biases Associated with Vulnerability to Bipolar Disorder

Bipolar disorder is associated with significant social and occupational impairments, as well as increased risk for substance abuse and suicide. More research is needed to identify potential mechanisms associated with vulnerability to the disorder. Previous research has identified altered processing of emotional information in bipolar and bipolar-prone individuals, including attentional biases which appear to differ based on the current affective state of the individual. The current study applied a sensitive measure of attention (i.e., eye-tracking) to assess whether vulnerability to bipolar disorder, as indexed by hypomanic personality traits, would be correlated with biases in attention to emotional facial stimuli, independent of mood state. Hypomanic personality traits were hypothesized to be associated with greater attention to happy and angry faces, as indexed by faster initial orientation, more frequent gazes, and longer gaze duration for these stimuli. Participants completed self-report measures assessing current mood symptoms, positive and negative affect, and hypomanic personality traits. They then completed two tasks assessing attention for emotional faces. The first was an eye-tracking task, which measured latency to first fixation, total gaze duration and total number of gazes for each emotional face category. The second was a spatial cueing task which assessed both attentional engagement with emotional …
Date: May 2013
Creator: Bain, Kathleen Marie
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Automated Treetop Detection and Tree Crown Identification Using Discrete-return Lidar Data (open access)

Automated Treetop Detection and Tree Crown Identification Using Discrete-return Lidar Data

Accurate estimates of tree and forest biomass are essential for a wide range of applications. Automated treetop detection and tree crown discrimination using LiDAR data can greatly facilitate forest biomass estimation. Previous work has focused on homogenous or single-species forests, while few studies have focused on mixed forests. In this study, a new method for treetop detection is proposed in which the treetop is the cluster center of selected points rather than the highest point. Based on treetop detection, tree crowns are discriminated through comparison of three-dimensional shape signatures. The methods are first tested using simulated LiDAR point clouds for trees, and then applied to real LiDAR data from the Soquel Demonstration State Forest, California, USA. Results from both simulated and real LiDAR data show that the proposed method has great potential for effective detection of treetops and discrimination of tree crowns.
Date: May 2013
Creator: Liu, Haijian
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Bioconcentration and Morphological Effects of Triclosan on Three Species of Wetland Plants (open access)

Bioconcentration and Morphological Effects of Triclosan on Three Species of Wetland Plants

Triclosan (TCS) is an antimicrobial compound found in several types of common household products. After being washed down the drain, TCS will then end up in the local watershed. Although numerous studies have been conducted to evaluate the fate and effects of TCS in aquatic environments, there have been no studies evaluating the role arbuscular mycorrhizal fungi (AM) play in a plants response to TCS exposure. Three species of wetland plants native North Texas were inoculated with AM spores and exposed to 0, 0.4 g/L and 4.0 g/L TCS concentrations. Root morphology of E. prostrata and S. herbacea showed AM and exposure responses. S. herbacea produced the greatest amounts biomass and TCS bioaccumulation, in all but one treatment. It also displayed opposing results to E. prostrata in measures of root length, root surface area, relative root mass, relative shoot mass and shoot:root ratio. TCS root tissue concentrations increased with increased exposures for both E. prostrata and S. herbacea. Even though E. prostrata had the lowest levels in each measure of biomass production, it had the highest amount of root TCS bioaccumulation in the AM inoculated 4.0 g/L treatment. H. laevis was between the other two species in terms of biomass …
Date: May 2013
Creator: Smith, Caleb M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Blood and Earth: Indivisible Territory and Terrorist Group Longevity (open access)

Blood and Earth: Indivisible Territory and Terrorist Group Longevity

The study of terrorism has been both broad in scope and varied in approach. Little work has been done, however, on the territorial aspects of terrorist groups. Most terrorist groups are revolutionary to one degree or another, seeking the control of a piece of territory; but for the supportive population of a terrorist group, how important is the issue of territory? Are the intangible qualities of territory more salient to a given population than other factors? Are territorially based terrorist groups more durable than their ideologically or religiously motivated cohorts? This paper aims to propose the validity of the territorial argument for the study of political terrorism.
Date: May 2013
Creator: Glass, Richard A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Blueline Concerto: Critical Essay (open access)

Blueline Concerto: Critical Essay

The purpose of this critical essay is two-fold. First, the essay presents a detailed critical analysis of my original composition, Blueline Concerto for bass trombone and wind ensemble. Second, using Blueline Concerto, the essay presents preliminary findings of my study to develop an approach to composing that takes into account the musicians' health, specifically regarding noise induced hearing loss (NIHL). Through various hypothesized composition- and orchestral-based approaches, I test effectiveness on changes in NIHL risk while also noting that artistic merit and compositional integrity is preserved.
Date: August 2013
Creator: Lamb, Christopher
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Brass Band History and Idiomatic Writing in Brass Music (open access)

Brass Band History and Idiomatic Writing in Brass Music

The purpose of this research was to explore historical perspective of brass music. There is a brief history of brass bands in Britain. Furthermore, the paper examines the differences between two brass band pieces in the repertoire, A Western Fanfare by Eric Ewazen and Brass Symphony by Jan Koetsier. Both of these pieces were compared and contrasted against the author's newly composed work for brass, Two Companion Pieces for Brass Ensemble. The paper covers different techniques commonly used in brass writing and points these techniques out in all three pieces.
Date: May 2013
Creator: Kahler, Elyse T.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Breaking Outside: Narratives of Art and Hawaii (open access)

Breaking Outside: Narratives of Art and Hawaii

This research examines the personal narratives of two contemporary non-native artists living and working on the island of Oahu, Hawaii. Issues related to narratives, power structures, artistic processes, insider/outsider dynamics, Hawaiian culture, island life, surfing, and the researcher's own experiences are woven together to formulate realizations surrounding alternative knowledge systems and the power of multiple or hidden narratives to the practice of art education.
Date: May 2013
Creator: Davidson, Allison B.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Characterization of Viscoelastic Properties of a Material Used for an Additive Manufacturing Method (open access)

Characterization of Viscoelastic Properties of a Material Used for an Additive Manufacturing Method

Recent development of additive manufacturing technologies has led to lack of information on the base materials being used. A need arises to know the mechanical behaviors of these base materials so that it can be linked with macroscopic mechanical behaviors of 3D network structures manufactured from the 3D printer. The main objectives of my research are to characterize properties of a material for an additive manufacturing method (commonly referred to as 3D printing). Also, to model viscoelastic properties of Procast material that is obtained from 3D printer. For this purpose, a 3D CAD model is made using ProE and 3D printed using Projet HD3500. Series of uniaxial tensile tests, creep tests, and dynamic mechanical analysis are carried out to obtained viscoelastic behavior of Procast. Test data is fitted using various linear and nonlinear viscoelastic models. Validation of model is also carried out using tensile test data and frequency sweep data. Various other mechanical characterization have also been carried out in order to find density, melting temperature, glass transition temperature, and strain rate dependent elastic modulus of Procast material. It can be concluded that melting temperature of Procast material is around 337°C, the elastic modulus is around 0.7-0.8 GPa, and yield …
Date: December 2013
Creator: Iqbal, Shaheer
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Classless: on Being Middle Class in America (open access)

Classless: on Being Middle Class in America

Classless: On Being Middle Class in America is a documentary film that explores what it means to be middle class in America. The film combines personal narrative, folksy reporting, and comedy as the film's director— Joe Brown, tries to reconcile his own status anxiety with everyday understandings of social class. Classless takes the form of a journey; the film travels through the American South, Northeast, and the Mountain West while trying to get at the heart of our middle class American Dream. Classless forwards three main arguments: (1) the American middle class is not as all-encompassing as seems; (2) Americans are more concerned about inequality than both politicians and the media suggest; and (3) many Americans are not actually middle class, economically speaking.
Date: May 2013
Creator: Brown, Joseph V.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Cold-formed Steel Framed Shear Wall Sheathed with Corrugated Sheet Steel (open access)

Cold-formed Steel Framed Shear Wall Sheathed with Corrugated Sheet Steel

Incombustibility is one important advantage of the sheet steel sheathed shear wall over wood panel sheathed shear wall. Compared to shear wall sheathed with plywood and OSB panel, shear wall sheathed with flat sheet steel behaved lower shear strength. Although shear wall sheathed with corrugated sheet steel exhibited high nominal strength and high stiffness, the shear wall usually behaved lower ductility resulting from brittle failure at the connection between the sheathing to frames. This research is aimed at developing modifications on the corrugated sheathing to improve the ductility of the shear wall as well as derive practical response modification factor by establishing correct relationship between ductility factor ? and response modification factor R. Totally 21 monotonic and cyclic full-scale shear wall tests were conducted during the winter break in 2012 by the author in NUCONSTEEL Materials Testing Laboratory in the University of North Texas. The research investigated nineteen 8 ft. × 4 ft. shear walls with 68 mil frames and 27 mil corrugation sheet steel in 11 configurations and two more shear walls sheathed with 6/17-in.OSB and 15/32-in. plywood respectively for comparison. The shear walls, which were in some special cutting arrangement patterns, performed better under lateral load conditions according …
Date: May 2013
Creator: Yu, Guowang
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp (open access)

Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp

Few studies have been conducted on the effectiveness of phytoremediation of pharmaceutical compounds, although the persistent and non-acutely toxic nature of many of these compounds in today's water bodies may yield an ideal application for this practice. To quantify the potential effectiveness of plant uptake, kinetic and proportional bioconcentration factors (BCFk, and BCFp, respectively) in nanograms (ng) carbamazepine and amiodarone per gram (g) wet weight plant tissue for Lemna spp. were determined utilizing a 14-day continuous flow-through study. Samples were analyzed using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) running in positive ion mode. Kinetic BCF was estimated at 0.538, while proportional BCF was estimated at 0.485. Kinetic BCF for the amiodarone study was estimated at 23.033, whereas proportional BCF was estimated at 41.340. Possible contamination of the C18 column and peristaltic pump failure may have impacted uptake results. In light of variability and current lack of research in the field, this work should be considered exploratory rather than conclusive.
Date: August 2013
Creator: Woodard, Jennifer Kristin
Object Type: Thesis or Dissertation
System: The UNT Digital Library