Digital Commons Network^™

Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal

Theses and Dissertations

The objective of this investigation was to examine the foraging patterns and population density of the Buff-bellied Hummingbird (Amazilia yucatanensis ) in Hidalgo County, TX. Previous studies showed that hummingbirds use flowers displaying traditional bird pollination (ornithophilous) characteristics: reddish coloration, tubular corolla, and extended anthers. Observation sessions noted type and frequency of flowering species utilized for nectar, characteristics, and number of individuals seen in each area. Amazilia yucatanensis showed higher use of ornithophilous flowers. Significant results found: f-ratio 5.45 > p-value (0.05) 3.24. Two highly utilized species showed the expected 20–40% sucrose content expected in ornithophilous flowers. Population density per …

Mobile Appointment Reminders In Patient-Centered Care: Design And Evaluation, Ying Wang

Theses and Dissertations

Reminder systems have great potential to enhance healthcare outcome if it can facilitate collaborative appointment management with accessible mobile communication technology in patient-centered care. Yet, Current appointment reminder systems are effective but not optimal (McLean, et al. 2016). Following the design science process delineated by Peffers et al. (2007) and other requirements, this study proposes a design of reciprocal reminder system that automates the process of appointment rescheduling for healthcare providers and patients in addition to confirmation and cancellation. Based on the premises of media synchronicity theory, media naturalness theory and stakeholder theory as kernel theories, this study develops a …

Sequencing Of The Complete Mitochondrial Genome Of Anastrepha Species, Francisco C. Rugama Ii

Theses and Dissertations

Several members of fruit flies in the vastly diverse Anastrepha (Schinner) genus (family Tephritidae), considered to be among the most important and devastating pests of vegetable and fruit crops, are distributed widely throughout the Americas. They attack several different kinds of fruit including citrus, which is of great economical importance in South Texas. The identification of these flies is based primarily on wing pattern and characteristics of the female genitalia, contrary to males, which cannot be distinguished at all. Misidentification of adults is a widespread problem, while identification at the larval stage is practically impossible. Currently, there are no published …

Boricua Type: Intersectional Hybrid Transcultural Art Concepts And Illustrations, Isaac Santiago

Theses and Dissertations

The concepts and artworks contained in this thesis embodies most of the research that I did in and outside the University. My particular experiences as a Puerto Rican, born and raised, and as a migrant artist in Mexico and Texas. Most of the research was made by trail and error independently or with little to no guidance. In conclusion I found my artistic self: technically, personally, and reached a high level of commitment to our community as a prepared professional.

Optical Method For High Magnification Imaging And Video Recording Of Live Cells At Sub-Micron Resolution, Jaime E. Romo Jr.

Theses and Dissertations

Optical microscopy, the most common technique for viewing living microorganisms, is limited in resolution by Abbe’s criterion. Recent microscopy techniques focus on circumnavigating the light diffraction limit by using different methods to obtain the topography of the sample. Systems like the AFM and SEM provide images with fields of view in the nanometer range with high resolvable detail, however these techniques are expensive, and limited in their ability to document live cells. The Dino-Lite digital microscope coupled with the Zeiss Axiovert 25 CFL microscope delivers a cost-effective method for recording live cells. Fields of view ranging from 8 microns to …

Wettability Of Nonwoven Polymeric Nanofiber Mats, Edgar Munoz

Theses and Dissertations

The wettability of heterogeneous materials has been attracting special interest by academia and industrial sector given the need to development self-cleaning Nonwoven nanofiber mats have demonstrated potential given its hydrophobicity granted by the ultimate structure of the system, small fiber diameter and small pores giving rise to effects such as the Cassie-Baxter. This thesis analyzed the wettability of a wide range of polymeric systems. Nanofiber mats were manufactured using the Forcespinning® technology. Samples were prepared at different polymeric concentrations and rotational speeds to alter fiber size; density of the mat was also altered to evaluate the effect of porosity on …

Knee Joint Internal Forces During Squat Jump Exercise, Ricardo Moreno

Theses and Dissertations

The purpose of this research is to investigate muscular ligament and joint contact forces produced during squat jump exercise. An inverse dynamics, two dimensional, leg model is used to describe the motion in the sagittal plane. The lower extremity model includes two bones, tibia and femur, tibio-femoral ligaments, and muscles such as quadriceps, hamstrings, and gastrocnemius. The ligaments are anatomically modeled as nonlinear strings, but the femoral condyle is modeled as a circle and the tibial plateau as a straight line. Experimental squat jump exercises are conducted to obtain the ground reaction forces, the angular accelerations, and centroid linear acceleration …

Using Machine Learning To Predict Student Achievement On The State Of Texas Assessment Of Academic Readiness Examination In Charter Schools, Christopher D. Gonzalez

Theses and Dissertations

The purpose of this study was to research and develop a way to use machine learning algorithms (MLAs) to predict student achievement on the State of Texas Assessment of Academic Readiness (STAAR), specifically in the charter school setting. Charter schools have the disadvantage of a constant influx in students, so providing historical student data in order to analyze trends proves difficult. This study expands on previous research done on students in secondary and post-secondary school and determining features that indicate success in these settings. The data used is from the district of IDEA Public Schools who focuses on providing education …

Ancient Maya Agricultural Resources In The Rio Amarillo Valley Near Copán, Honduras, Bryce Matthew Brown

Theses and Dissertations

The purpose of this study was to use soil physical and chemical analyses to better understand the ancient agricultural landscape around the ancient Maya cities of Rio Amarillo and Piedras Negras, two tributary sites to Copan, Honduras. Our primary objective was to determine whether a mass erosion event around 800 A.D. occurred which could have caused crop failure and famine or if stable soil conditions persisted during the collapse of these city-states. Stable carbon isotope analysis of the humin fraction of the soils showed that much of this valley was used anciently for agriculture, including hillslopes and hilltops; however, there …

Control Of Matrix Metalloproteinases In A Periodontitis Model: Molecules That Trigger Or Inhibit Mmp Production, Catalina Matias Orozco

Theses and Dissertations

In periodontitis, there is a disruption in the homeostasis of the oral microbiome by peridontopathogenic bacteria. However, while bacteria is essential for periodontitis to occur, the severity, pattern and progression of the disease is not solely determined by the microbial burden, and in fact has a lot to do with the overwhelming host inflammatory response. The response can vary even in two individuals with similar periodontopathogenic profiles. The host response leads to extracellular matrix (ECM) destruction, loss of attachment, alveolar bone resorption and eventually, edentulism. The host's reaction is orchestrated by proinflammatory cytokines and chemokines and matrix metalloproteinases (MMPs). MMPs …

An Investigation Of Ssglux, A Glucosidase Co-Expressed With Cslf6 In Oat (Avena Sativa) And Barley (Hordeum Vulgare), Michael Christopher Gines

Theses and Dissertations

Mixed Linkage Glucan (MLG, or (1,3;1,4)-ß-D glucan) is a component of cell walls for major cereal crops and is significant to food and beverage industries. To better understand genetic factors affecting MLG content in oats, this study investigates the presence of glucosidases likely to participate in MLG production. A glucosidase showing co-expression with CslF6—the primary gene responsible for MLG synthesis—could indicate a hand in MLG production by association. Reference genes for expression analysis as well as glucosidase candidates were first selected using in silico methods. In both cases, barley was used as model species because it has abundant public bioinformatic …

If This Heart Had A Mouth: A Forbidden Romance Narrated Through Mimesis: Poems, Julieta V. Corpus

Theses and Dissertations

If This Heart Had a Mouth consists of forty-two poems where love is the catalyst for a multitude of emotions, ranging from falling in love, to hopelessness, to a begrudging kind of acceptance at losing the beloved to somebody else. To create all forty-two poems, 23 written in Spanish, and 19 poems written in English, I employed the literary device called Mimesis which entails deriving an original poem from someone else's work.

To create each poem, I followed another poet’s original work, line by line. I imitated that poet’s rhythm through their use of meter. I counted the number of …

False Positives On Neuropsychological Measures Of Effort Among Bilingual Neurologically Intact Mexican Americans, Arnoldo Amador Jr.

Theses and Dissertations

The present study examines the performance of bilingual Mexican Americans on neuropsychological measures of effort in language and visual-perceptual formats. Optimal/suboptimal effort cutoff scores derived from monolingual English Speakers were used to test participants divided by language of administration and bilingual groupings based upon Spanish-English difference scores on the Woodcock Munoz Language Survey-Revised Picture Vocabulary subtest. Participants produced more false positives (misidentification of suboptimal effort) on the Reliable Digit Span, a language formatted measure, and similar rates of false positives on visual-perceptual effort measures: Test of Memory Malingering and the Dot Counting Test as compared to established rates using monolingual …

An Investigation Of Perceived Principal Stress And Its Impact On Principals In Southwest Georgia, Dorothy Young Ingram

Theses and Dissertations

The purpose of the study was to determine to what extent southwest Georgia principals perceive they are stressed, identify principal stressors and how the stressors impact the principals’ work. Principals are leaders of school building who are experiencing increased stress. Therefore; it is important to understand what causes principal stress as well as how the stressors impact principal work. Principals are expected to maintain building safety, student safety, student achievement, retention of quality teachers, as well as act as instructional leaders. The mixed method study of public elementary school principals was conducted in four southwest Georgia school districts. The researcher …

Use Of The Mmpi-2 Masculine-Feminine Pathology Scale In Determining Gender-Related Symptom Expressions Among Outpatients, Priyanka M. Parikh

Theses and Dissertations

Gender exerts a strong influence over psychopathology experience and expression. The Masculine-Feminine Pathology (Mfp) scale is a recently developed research scale for the Minnesota Multiphasic Personality Inventory, Second Edition (MMPI-2), intended to reflect gender-influenced psychopathological symptoms. The current study was designed to examine whether Mfp scores serve as a useful moderator in the interpretation of MMPI-2 scores in terms of identifying gender-related symptom expression in an outpatient adult psychiatric sample. The sample consisted of 186 participants who had undergone outpatient psychotherapy. MMPI-2 scales include selected clinical scales, Restructured Clinical (RC) scales, content scales, supplementary scales, and Personality Psychopathology-Five (PSY-5) scales …

Non-Invasive Real Time, Accurate And Affordable Monitoring Of Hemoglobin And Vital Parameters For Icu Patients, Harsh S. Modi

Theses and Dissertations

The measurement of hemoglobin concentration (Hb), oxygen consumption (mL and %), and partial pressure of oxygen inside the lungs are vital parameters in early prediction of respiratory diseases such as sepsis, septic shock, acute respiratory distress syndrome (ARDS) etc. The availability of these parameters in real time can play a crucial role in management of modes and parameters of the ventilators. The real time monitoring of patient’s vital signals in intensive care units can reduce the number of blood tests, time and cost spent inside the intensive care units. The medical conditions such as blood loss from surgery or an …

Ethnicity And Poetry: A Systems Theory Approach To Contemporary African American And Mexican American Poetry, Antonio Paniagua Guzman

Theses and Dissertations

Given the ongoing ethnic transformation of the current society of the United States, contemporary sociologists have extensively studied ethnic relations from diverse theoretical and methodological approaches. Despite the vast sociological research recently developed, the literary-based methodological approach remains partially uncultivated. This study explores motivations and patterns of minority groups’ ethnic performance in contemporary poetry by analyzing inter and intra-group similarities and differences of diverse linguistic and cultural traits. From secondary data analysis, this study examines four hundred poems authored by forty contemporary African American and Mexican American writers experientially connected to the state of Texas. Grounded in systems theory, this …

The Role Of Biotic And Environmental Factors In Spatial And Temporal Variability Of Indian River Lagoon Copepod Communities, Hannah G. Kolb

Theses and Dissertations

The role of zooplankton communities as the link between phytoplankton and secondary consumers is dependent on the species make-up of the copepod community. Copepods often dominate zooplankton in numbers and biomass and are frequently the dominant grazers. Species variabilities in behavioral and morphological traits, and seasonal variances in species make-up, have the potential to alter trophic dynamics in planktonic communities. The goal of this study was to identify the driving forces behind copepod community composition and better understand the role of key species in the Northern Indian River Lagoon (N-IRL). Copepods made up 76% of the N-IRL zooplankton community and …

Developing The Three Dimensional Tumor Model For Melanoma Drug Screening, Guochang Ye

Theses and Dissertations

Two-dimensional (2D) Tissue Culture Treated Plastic (TCTP) is widely used for cancer drug screening and has dominated the field for a long time. Compared with traditional two dimensional cell culture, a three dimensional tumor model may able to provide more reliable experimental results related to drug screening and discovery. With the development of nanoparticle chemotherapies, there is a need for ways to better investigate and characterize the effect of the 3D tumor environment. Cerium oxide nanoparticles, Nanoceria, is one of the potential solutions being explored for treating melanoma in the future in combination with conventional chemotherapies. This is attributed to …

Investigation Of Dynamic Biological Systems Using Direct Injection And Liquid Chromatography Mass Spectrometry, Adam Clayton Swensen

Theses and Dissertations

In biological systems, small changes can have significant impacts. It is, therefore, very important to be able to identify these changes in order to understand what is occurring in the organism. In many cases, this is not an easy task. Mass spectrometry has proven to be a very useful tool in elucidating biological changes even at a very small scale. Several different mass spectrometry based techniques have been developed to discover and investigate complex biological changes. Some of these techniques, such as proteomics, have been through years of development and have advanced to the point that anyone can complete complex …

The Effects Of L-Cysteine On Alzheimer's Disease Pathology In Apoe2, Apoe3, And Apoe4 Homozygous Mice, Stephen Gerard Cieslak

Theses and Dissertations

The APOE gene is of profound importance regarding the onset of Alzheimer's disease (AD). From the small physical differences among the protein products of the isoforms of this gene arises a profound difference in their physiologies. For example, the APOE2 isoform confers resistance to AD, the APOE3 isoform confers neutral susceptibility to AD, and the APOE4 isoform confers proneness to AD. L-cysteine is an amino acid that has several anti-AD properties, among which are its ability to sequester iron and form glutathione – a powerful antioxidant – and therefore may be a promising potential dietary supplement for ameliorating AD …

Passively Estimating Index Of Refraction For Specular Reflectors Using Polarimetric Hyperspectral Imaging, Jacob A. Martin

Theses and Dissertations

As off-nadir viewing platforms becoming increasingly prevalent in remote sensing, material classification and ID techniques robust to changing viewing geometries must be developed. Traditionally, either reflectivity or emissivity are used for classification, but these quantities vary with viewing angle. Instead, estimating index of refraction may be advantageous as it is invariant with respect to viewing geometry. This work focuses on estimating index of refraction from LWIR (875-1250 wavenumbers) polarimetric hyperspectral radiance measurements.

Effects Of Tethering Placement And Linker Variations On Antibody Stability On Surfaces, Rebecca Ellen Grawe

Theses and Dissertations

An antibody microarray consists of antibody bound to a surface. Antibody microarrays have great potential in many fields, particularly as a tool to detect antigens. Unfortunately, antibodies suffer from poor performance. A greater understanding of how antibodies interact with surfaces would improve microarray design and performance, but experimental methods fall short of being able to observe these interactions. Therefore molecular simulation has emerged as the primary method to study protein/surface interactions.The simulations here were coarse grain simulations performed using the model of Karanicolas and Brooks. Additionally, an advanced surface model was used that allows for different surface chemistries. PyMBAR analysis …

Endocannabinoid-Mediated Synaptic Plasticity In The Ventral Tegmental Area And Hippocampus, Lindsey Nicole Friend

Theses and Dissertations

Synaptic plasticity is the process whereby connections between neurons can be altered in an experience dependent manner. For example, drugs of abuse alter plasticity in the ventral tegmental area (VTA) of the midbrain. A large amount of research has been applied to uncovering the mechanism whereby synapses on the reward signaling dopamine cells is altered, however, less is known regarding the VTA inhibitory GABA neurons. Our objective was to examine the ability of GABA neurons to exhibit plasticity, and determine how drugs of abuse could influence it. Here we report a novel type of plasticity of excitatory neurotransmission onto VTA …

Design And Development Of A Physiological Stress Monitoring/Alert System Using A Wristband, Ritesh Varma Pathapati Thyagaraju

Theses and Dissertations

The design and development of wearable physiological systems for stress monitoring have gathered a lot of attention during the past few years. These systems have undergone much-needed development to tackle long-term effects such as a headache, depression, insomnia, high blood pressure, confusion, inability to make correct choices, etc. Accurately measuring physiological signals that are helpful to detect stress in its early stages using wearable technology have long been a goal in the healthcare industry. Current commercial products such as Fitbit and Empatica only monitor either the heart rate (Fitbit) or electrodermal activity in real time (Empatica) but these devices have …

Consumer Likelihood To Complain In The U.S. Commercial Airline Industry, Xinpei Lu

Theses and Dissertations

Consumer emotions play an important role in the marketplace nowadays, which can either directly or indirectly affect the marketing outcomes. Consumer complaints are believed to occur if consumers begin to generate negative emotions due to an unfavorable service experience. However, there are also existing controversies. Moreover, males and females tended to show different attitudes towards complaining in different situations. There is a great significance of doing the research of consumer complaints in commercial airline industry because a majority of the predominant research concentrates on the consumer complaint behaviors in market places such as restaurant, hospital, hotel, and shopping mall. The …

An Examination Of The 16pf Validity Scales As Predictors Of The Scale Of Accurate Personality Prediction (Sapp), Katherine E. Schmieder

Theses and Dissertations

The Scale of Accurate Personality Prediction (SAPP) was derived from the 16 Personality Factor Questionnaire (16-PF) as a measure of self-knowledge by comparing the degree of similarity of a participant’s predicted and obtained 16 PF results. The purpose of this study was to examine the utilization of the16PF validity scales as potential predictors of an individual’s score on the Scale of Accurate Personality Prediction (SAPP). A series of multiple regression analyses were performed on the current database of 641 respondents. Additionally, to provide additional validity, the database was split into two halves, and the multiple regression analyses were run on …

Correlates Of The Minnesota Multiphasic Personality Inventory-2 Restructured Form (Mmpi-2-Rf) Scores For Asian Indian College Students, Saloni Taneja

Theses and Dissertations

This study was designed to investigate empirical correlates of the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) for Asian Indian college students using the NEO Five Factor Inventory-3, College Maladjustment Scales and Measures of Psychosocial Development. The study utilized an Asian Indian college student sample (N=48) from a private university in Florida. Pearson Product Moment correlations were computed to establish correlates of the MMPI-2-RF scale scores. Overall, a large number of significant correlates with large effect sizes were found across the three measures. Some correlates found in the study provided an expansion for the interpretation of the MMPI-2-RF scales for Asian …

Digital Quorum Sensing For Self-Organizing Malware, Mark E. Fioravanti Ii

Theses and Dissertations

INTRODUCTION: Malware authors present an interesting problem for the security community as they evolve and adapt to overcome network and host defenses. The determined adversary is a special class of malware author who may attempt to disrupt national interests. These adversaries may seek potentially novel Command and Control (C2) channels to coordinate their activities. Isolated and air-gapped networks pose an interesting challenge that these adversaries must adapt to in order to maintain persistence on these networks. In this work we propose that a determined adversary may seek to implement a digital quorum sensing system inspired by the quorum sensing systems …

A Self-Organized Approach For Detecting Communities In Networks, Ben Collingsworth

Theses and Dissertations

The community structure of networks reveals hidden information about the whole network structure that cannot be discerned using other topological properties. Yet, the importance of identifying community structure in networks to many fields such as medicine, social sciences and national security, calls for better approaches for performing this identification. The prevalent community detection algorithms, such as the one proposed by Girvan and Newman, utilize a centralized approach that is unlikely to scale to very large networks and does not handle dynamic networks. Further, existing algorithms provide limited information regarding community overlap, where an individual participates in multiple communities. We propose …