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  Partner: UNT Libraries
 Decade: 2010-2019
 Collection: UNT Theses and Dissertations
9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

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Date: May 2012
Creator: Nalam, Vamsi J.
Description: The activity of plant 9-lipoxygenases (LOXs) influences the outcome of Arabidopsis thaliana interaction with pathogen and insects. Evidence provided here indicates that in Arabidopsis, 9-LOXs facilitate infestation by Myzus persicae, commonly known as the green peach aphid (GPA), a sap-sucking insect, and infection by the fungal pathogen Fusarium graminearum. in comparison to the wild-type plant, lox5 mutants, which are deficient in a 9-lipoxygenase, GPA population was smaller and the insect spent less time feeding from sieve elements and xylem, thus resulting in reduced water content and fecundity of GPA. LOX5 expression is induced rapidly in roots of GPA-infested plants. This increase in LOX5 expression is paralleled by an increase in LOX5-synthesized oxylipins in the root and petiole exudates of GPA-infested plants. Micrografting experiments demonstrated that GPA population size was smaller on plants in which the roots were of the lox5 mutant genotype. Exogenous treatment of lox5 mutant roots with 9-hydroxyoctadecanoic acid restored water content and population size of GPA on lox5 mutants. Together, these results suggest that LOX5 genotype in roots is critical for facilitating insect infestation of Arabidopsis. in Arabidopsis, 9-LOX function is also required for facilitating infection by F. graminearum, which is a leading cause of Fusarium head ...
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161 Glass: Site Specific Music in an Artistic Context

161 Glass: Site Specific Music in an Artistic Context

Date: May 2010
Creator: Rusnak, Christina S.
Description: The composition 161 Glass is a 17-minute musical work with percussion, wind and brass instruments in which the intersection of mid-century architecture, and the art and culture of a dynamic city are inextricably linked. Through this paper, I explore the process of composing a musical work in relationship to the significance of site specific context. The paper begins by defining the concept of site specific art works; then reviews the discourse of the intersection of art, music and architecture. I then delve into the cultural and geographic context surrounding this project from the modern era through the present, and how those perspectives apply to the building and my piece. I reveal how the composition relates the musical ideas to the site. Finally, I describe the collaborative process between myself, the musicians and the Dallas Contemporary staff.
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A 018μm Cmos Transmitter for Ecg Signals

A 018μm Cmos Transmitter for Ecg Signals

Date: December 2013
Creator: Kakarna, Tejaswi
Description: 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.
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3D Reconstruction Using Lidar and Visual Images

3D Reconstruction Using Lidar and Visual Images

Date: December 2012
Creator: Duraisamy, Prakash
Description: In this research, multi-perspective image registration using LiDAR and visual images was considered. 2D-3D image registration is a difficult task because it requires the extraction of different semantic features from each modality. This problem is solved in three parts. The first step involves detection and extraction of common features from each of the data sets. The second step consists of associating the common features between two different modalities. Traditional methods use lines or orthogonal corners as common features. The third step consists of building the projection matrix. Many existing methods use global positing system (GPS) or inertial navigation system (INS) for an initial estimate of the camera pose. However, the approach discussed herein does not use GPS, INS, or any such devices for initial estimate; hence the model can be used in places like the lunar surface or Mars where GPS or INS are not available. A variation of the method is also described, which does not require strong features from both images but rather uses intensity gradients in the image. This can be useful when one image does not have strong features (such as lines) or there are too many extraneous features.
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3GPP Long Term Evolution LTE Scheduling

3GPP Long Term Evolution LTE Scheduling

Date: December 2013
Creator: Alotaibi, Sultan
Description: 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 ...
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Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation

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

Access: Use of this item is restricted to the UNT Community.
Date: August 2013
Creator: Fogueri, Uma
Description: 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 ...
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Ability of Offenders with Psychopathic Traits to Simulate Cognitive and Affective Empathy

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

Date: August 2013
Creator: Robinson, Emily V.
Description: 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.
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Absorptive Capacity:  An Empirical Examination of the Phenomenon and Relationships with Firm Capabilities

Absorptive Capacity: An Empirical Examination of the Phenomenon and Relationships with Firm Capabilities

Date: May 2012
Creator: Daspit, Josh
Description: The field of strategic management addresses challenges that firms encounter in an attempt to remain competitive. The ability to explain variation in firm success through examination of knowledge flows has become a prominent focus of research in the strategic management literature. Specifically, researchers have sought to further examine how firms convert knowledge, a phenomenon conceptualized as absorptive capacity. Absorptive capacity is the firm’s ability to acquire, assimilate, transform, and exploit knowledge. Few studies have captured the richness and multi-dimensionality of absorptive capacity, and it remains to be understood how the dimensions of the phenomenon convert knowledge. Furthermore, how absorptive capacity influences the firm remains to be understood. To address these research gaps, this dissertation seeks to (1) determine how absorptive capacity converts knowledge, and (2) determine how absorptive capacity influences firm capabilities. The research questions are investigated using structural modeling techniques to analyze data collected from software-industry firms. The findings offer contributions to the absorptive capacity and capability literatures. For example, absorptive capacity is hypothesized to consist of complex relationships among its internal dimensions. However, findings of this study suggest the relationships among the dimensions are linear in nature. This finding is in line with the theoretical foundations of and ...
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Academic Advising Professional Characteristics and Standards: Do Academic Advisors Follow Recognized Professional Standards in Their Work?

Academic Advising Professional Characteristics and Standards: Do Academic Advisors Follow Recognized Professional Standards in Their Work?

Date: May 2014
Creator: Shelton, Kiesha R.
Description: There were two main purposes of this quantitative study. The first purpose was to identify characteristics associated with the selected sample of academic advisors that comprise study. Secondly, the study sought to determine how well work related activities of a selected population of academic advisors correlate with professional characteristics constructs and professional standards constructs of academic advising as a profession. The study used Habley’s (1986) characteristics of a profession to derive the studies professional characteristic construct, education activities, research activities, and professional development activities as it relates to a selected group of academic advisors work related activities. The studies professional standards construct was derived from five Council for the Advancement of Standards (CAS) professional standards for academic as it relates to a selected group of academic advisors work related activities. The study of 78 out of 210 identified full-time academic advisors at two-and four-year public colleges and universities in the North Texas Region utilized a multidimensional researcher-developed Web survey instrument designed to measure professional standards and characteristic within the field of academic advising. Study results reinforced current criticism of research and education activities within the field of academic advising showing that the lack of scholarly research and education activities among ...
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The Academic and Athletic Experiences of African-american Males in a Division I (Fbs) Football Program

The Academic and Athletic Experiences of African-american Males in a Division I (Fbs) Football Program

Date: December 2013
Creator: Salinas, Silvia M.
Description: This study investigated the academic and athletic experiences of African-American males in a Division I football bowl subdivision football program. Critical race theory, identity development model, and social learning model were the theoretical frameworks used as the critical lenses in a qualitative design to examine the participants. The participants’ responses were analyzed and interpreted using thematic analysis. A qualitative research design, which included individual interviews with 10 second year African-American male football players, was used to address this research problem. The goal was to bring together both the psychological and sociological perspectives and to challenge participants to candidly describe their academic and athletic experiences and attitudes toward obtaining an undergraduate degree. Four themes were determined in the data analysis: differential treatment and determining oneself, time management, relationships, and career aspirations. In relation to the theoretical frameworks, the development of self-confidence and knowledge of balancing their academic and athletic schedules was critical for all participants. The sense of feeling different and challenged because of the differences in culture and experience was evident. From this study, university and collegiate athletics administrators may better understand the backgrounds, challenges, and learning needs of this population. As a result, higher education personnel may improve the ...
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