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Articles 4381 - 4410 of 30814
Full-Text Articles in Entire DC Network
Age And Sex Of Wild Asian Elephants Observed In And Around Protected Areas In Kanchanaburi, Thailand, Leah D. Wersebe
Age And Sex Of Wild Asian Elephants Observed In And Around Protected Areas In Kanchanaburi, Thailand, Leah D. Wersebe
Theses and Dissertations
This study observed the wild Asian elephant population in and around Salakpra Wildlife Sanctuary and found a greater proportional presence of adults and subadults than calves and infants per observation, and a greater proportion of males than females outside of the protected area compared to inside the protected area.
Black College Students Perceptions Of The Covid-19 Vaccine Mandate, Rickae Rodney
Black College Students Perceptions Of The Covid-19 Vaccine Mandate, Rickae Rodney
Theses and Dissertations
This study explored Black college students’ perceptions of COVID-19 related mandates. Black college students with higher perceptions of racism, stronger ethnic identity, and greater distrust in science were expected to have more negative attitudes about COVID-19 vaccine and mask mandates. Results varied when relationships were tested.
Skilled Workers’ Mobility And Attrition: The Case Of Florida Emergency Medicine Physicians, Vassina Hassane Meite
Skilled Workers’ Mobility And Attrition: The Case Of Florida Emergency Medicine Physicians, Vassina Hassane Meite
Theses and Dissertations
Emergency medicine (EM) physicians constitute the front line of healthcare providers. They work swiftly to address critical situations, diagnose illnesses, and stabilize patients. Amidst a growing need and shortage of EM physicians, this longitudinal descriptive study captures EM physicians’ preferences for practice locations by studying Florida EM physicians’ relocation patterns between 2006 and 2020. Esti- mates from a Cox Proportional-Hazards model and fixed effects logistic regressions suggest that wage amenities are not a strong determinant of relocation over time. Physician attrition and relocation are instead more saliently affected by high work volumes within the EM physician’s primary work location.
The Rise Of Mercury: The Economic And Health Impacts Of Artisanal Gold Mining In Colombia, Jilmar D. Robledo Caicedo
The Rise Of Mercury: The Economic And Health Impacts Of Artisanal Gold Mining In Colombia, Jilmar D. Robledo Caicedo
Theses and Dissertations
Gold prices triggered mining booms in Colombia, leading to wealth and mercury pollution. These effects on human health remain unknown. This research investigates the effect of gold mining finding a significant effect on fetal deaths reduction, suggesting gender and gestational age are fundamental to understanding the interplay of gold mining.
“Who Will Guard The Guards Themselves ”: A Phenomenological Discourse Analysis On How Whiteness And White Supremacy Are Upheld By White Hearing Officers On Community College Campuses, Amanda Jane Mesirow
“Who Will Guard The Guards Themselves ”: A Phenomenological Discourse Analysis On How Whiteness And White Supremacy Are Upheld By White Hearing Officers On Community College Campuses, Amanda Jane Mesirow
Theses and Dissertations
The purpose of this study was to determine how whiteness and white supremacy are upheld by white hearing officers on community college campuses. The literature shows that racial bias exists in K-12 discipline systems, that no reporting mandates on demographics exist in higher education conduct, and that community colleges often serve minoritized students. Therefore, the problem statement centers on the connection between community colleges conduct systems and whiteness/white supremacy.Data was collected via interviews with three community college conduct practitioners, as well as a review of documents from their institutions’ conduct offices. The study’s research methods were phenomenological discourse analysis and …
A Help Or Hindrance? Team Leader Behaviors And The Team Climate Of Innovation, Matthew Brady Johnson
A Help Or Hindrance? Team Leader Behaviors And The Team Climate Of Innovation, Matthew Brady Johnson
Theses and Dissertations
While the nature of teamwork in organizations is ever-evolving, the utilization of teams in some form has continued to increase over the past several decades. While creativity is generally regarded as an individual-level phenomenon, innovation tends to occur as an emergent process at the team level, so rather than only hiring and rewarding star performers, organizations should cultivate and protect the team’s climate for innovation. A particularly impactful contextual factor in team climate is the team leader’s behavior. Therefore, the team leader’s contribution to the climate should work to promote innovation rather than discourage it. A cross-sectional, correlational study surveyed …
Electronic Books: Educational Enhancement Or Novelty?, Felipe O. Reyes
Electronic Books: Educational Enhancement Or Novelty?, Felipe O. Reyes
Theses and Dissertations
The study’s purpose was to explore if there was a statistically significant difference in reading comprehension of non-Limited English Proficient students when reading eBooks compared to printed books. Second, it explored if there was a statistically significant difference in Limited English Proficient students. Third, it explored if there was a statistically significant difference between non-Limited English Proficient and Limited English Proficient students while reading in neither format. The research sample of the study drew from the population (N=8,100) of students at the middle school level within a district in south Texas who participated in the Accelerated Reader program during …
Vertical Transmission Of Zika Virus In Monodelphis Domestica, Mohini Moulick
Vertical Transmission Of Zika Virus In Monodelphis Domestica, Mohini Moulick
Theses and Dissertations
Zika Viral infection in pregnant women may lead to infants born with microcephaly and other neurological complications, making Zika viral research imperative. Prior research demonstrated Monodelphis domestica to be a unique animal model for Zika virus studies, and viral proteins were detected in brain tissue of juveniles after intracerebral inoculation of infants. We wanted to determine if we can detect a viral protein, non-structural protein 1 (NS1), in brain tissue after intraperitoneal inoculation and we found it to be possible through immunohistochemistry (IHC) analysis. We also investigated if inoculated dams (mothers) would give rise to Zika positive pups (natural inoculation), …
Design And Implementation Of A Load Sensor In A Bearing Adapter Assembly For Freight Railcar Applications, Prince E. Mensah
Design And Implementation Of A Load Sensor In A Bearing Adapter Assembly For Freight Railcar Applications, Prince E. Mensah
Theses and Dissertations
The U.S. freight rail network, which covers approximately 140,000 route miles, is commonly regarded as the largest, safest, and most economical freight system in the world. It generates more than 167,000 jobs nationwide and has additional advantages over other modes of transportation, such as lower costs for logistics, public infrastructure upkeep, and decreases in traffic congestion, highway deaths, fuel consumption, and greenhouse gas emissions. Knowing the exact weight of cargo hauled by freight railcars can help avoid exceeding the loading thresholds set by the Association of American Railroads (AAR). Moreover, knowing the exact load applied to each bearing on the …
Vibration-Based Machine Learning Models For Condition Monitoring Of Railroad Rolling Stock, Sergio M. Martinez
Vibration-Based Machine Learning Models For Condition Monitoring Of Railroad Rolling Stock, Sergio M. Martinez
Theses and Dissertations
One of the primary causes of rail rolling stock derailments is attributed to bearing and wheel axle failures. The health of train bearings is primarily monitored at target locations through wayside detection systems. This practice is susceptible to bearing failure and potential derailments at points in between these wayside systems. To remedy this, the University Transportation Center for Railway Safety (UTCRS) has developed a wireless onboard monitoring system that can continuously monitor the vibration response, which directly correlates to the health of bearings. This data is used to train regression-based machine learning algorithms and long-term prediction neural networks to predict …
Two-Dimensional Nanomaterials And Nanocomposites For Sensing, Separation, And Energy Applications, Md Ashiqur Rahman
Two-Dimensional Nanomaterials And Nanocomposites For Sensing, Separation, And Energy Applications, Md Ashiqur Rahman
Theses and Dissertations
Two-dimension (2D) nanomaterials have gained popularity for the last few decades due to their excellent mechanical, electrical and thermal properties. These unique properties of 2D nanomaterials can be exploited in various applications specially in sensor, energy, and separation devices. In this study, the sensing and energy generation performance of PVDF/PAni fiber mat systems made by the forcespinning method with and without graphene coating. The graphene-coated nanocomposites show an average output voltage of 75 mV (peak-to-peak) which is 300% higher compared to bare fiber mats and an output current of 24 mA (peak-to-peak) by gentle finger pressing. Moreover, the graphene-coated PVDF/PAni …
Manufacturing Of A Flexible Piezoelectric Nanogenerator By Functionalizing Polyvinylidene Fluoride With Lithium Tantalate And Multiwalled Carbon Nanotubes For Energy Harvesting And Sensing Applications, Islam Uddin Shipu
Theses and Dissertations
Mechanical energy is one of the readily accessible green energy sources that could be employed to meet the small-scale energy requirement. In order to capture mechanical energy, power the next generation of electronic gadgets, and health monitoring flexible piezoelectric nanogenerators made of light weight polymers and carbon nanotubes have drawn a lot of attention. Lithium tantalate (LiTaO3), a ferroelectric substance, was prepared here and utilized to create a flexible piezoelectric nanogenerator (FPNG). A compact piezoelectric nanogenerator that successfully transfers mechanical energy into electricity was then created using lightweight polyvinylidene fluoride (PVDF), multi-walled carbon nanotube (MWCNT), and LiTaO3 nanoparticles. To create …
Indium Doped Zinc Stannate-Pdms Based Piezoelectric Generator For Harvesting Mechanical Energy And Sensory Application, Tamanna Zakia
Indium Doped Zinc Stannate-Pdms Based Piezoelectric Generator For Harvesting Mechanical Energy And Sensory Application, Tamanna Zakia
Theses and Dissertations
Piezoelectric materials are comparatively new among other alternative energy sources. Harvesting waste mechanical energy through these materials can be a potential solution of the increasing energy demand. In response to applied mechanical stress, piezoelectric materials accumulate electric charges on their surface. Upon connecting with a circuit, accumulated charges can flow and generate electricity. Based on this hypothesis piezoelectric nano-generator has been fabricated. Binary semiconducting oxides such as ZnO, TiO2 and SnO2 have attracted immense interest as they have unique properties of electron mobility. However, there is always a need for specially designed semiconductors to better match with the properties. This …
A Preliminary Characterization And Assessment Of Mesophotic Octocoral Microbiomes In The Western Gulf Of Mexico, Edward P. Gniffke
A Preliminary Characterization And Assessment Of Mesophotic Octocoral Microbiomes In The Western Gulf Of Mexico, Edward P. Gniffke
Theses and Dissertations
Mesophotic Coral Ecosystems are highly diverse and productive ecosystems in the western Gulf of Mexico which are composed of, in part, by octocorals (subclass Octocorallia). Despite their importance as foundational organisms octocorals are an understudied group in this region, with little known about their microbial community. Ninety-eight Octocoral samples collected from the western and northwestern Gulf of Mexico were sequenced using 16S rRNA sequencing to characterize their microbial communities. The sequenced microbiomes were generally low in diversity composed of a few core microbial taxa. Octocoral group was the main driver of microbiome composition as opposed to depth, season, region, and …
The Effects Of Low Volume High-Intensity Interval Training Vs. Moderate-Intensity Interval Training With Blood Flow Restriction On Body Composition, Hormone Concentration, And Arterial Elasticity In Overweight And Obese Male Adults, Alexis Lopez
Theses and Dissertations
PURPOSE: This study compared the effects of HIIT and MIIT+BFR on the adaptations in body composition, salivary hormone concentration, peak oxygen uptake, anaerobic parameters, and arterial elasticity in young overweight and obese male adults.
RESULTS: There was a significant increase in total BMC (p<0.01), leg BMC (p<0.05), and trunk BMC (p<0.05) from baseline in response to HIIT. MIIT+BFR significantly increased LFM/TFM Ratio from baseline (p<0.01). HIIT significantly decreased AIx@75 (p<0.05) and CI (p<0.05). There was a significant increase in ISO 180o Away (p<0.05), Thor Begin. (p<0.01), and Thor Mid. (p<0.05) in response to HIIT. MIIT+BFR had a superior increase in Thor Mid. (p<0.05) and significantly increased ISO 180o Toward (p<0.01), VO2peak (p<0.05), and VO2peak:Time (p<0.05). In the last training session, HIIT significantly increased salivary leptin (p<0.05), but MIIT+BFR had a superior increase in salivary leptin (p<0.01) from pre- to post exercise.
CONCLUSION: HIIT significantly improved total BMC, leg BMC, trunk BMC, and AIx@75 but decreased CI from baseline. HIIT increased quad muscle strength, whereas MIIT+BFR increased hamstring muscle strength. HIIT and MIIT+BFR significantly increased peak torque in Thor Mid and salivary leptin. Only MIIT+BFR significantly improved VO2peak.
Effect Of Pre-Growth Conditions On Foodborne Pathogen Survival Kinetics In Fresh Produce, Avninder Kaur
Effect Of Pre-Growth Conditions On Foodborne Pathogen Survival Kinetics In Fresh Produce, Avninder Kaur
Theses and Dissertations
World-wide consumption of fresh-cut produce has seen a dramatic increase over the past few decades. However, fresh-cut produce has been implicated in several illness outbreaks due to contamination with foodborne bacterial pathogens. Post-harvest contamination during handling and processing is considered rare but several influencing factors are often overlooked. Specifically, studies have reported the growth, survival, and death kinetics of foodborne bacterial pathogens such as E. coli O157: H7, Salmonella and Listeria monocytogenes in different fresh and fresh-cut produce. The effect of various factors such as storage temperature, time, and relative humidity are widely explored. It is increasingly evident that microbial …
Developing Control System For Manufacturing Processes, Md Shahriar Forhad
Developing Control System For Manufacturing Processes, Md Shahriar Forhad
Theses and Dissertations
Process control has been a critical component in today's manufacturing industry. Industrialists nowadays want reliable control to assure precision manufacturing. Modern control systems must be more dynamic, so that any needed modifications may be made quickly to accomplish the desired product change. For innovative research and development, system customization is critical to ensure freedom for experimental works. In addition, full control of manufacturing systems is necessary to realize and implement Industry 4.0. Often, it is difficult to achieve such control due to limited access to proprietary equipment. To this end, this thesis focuses on developing a custom control platform for …
Professional Development For Teaching In The Digital Age: Addressing Teachers’ Digital Competency, Blanca Nery Ibarra
Professional Development For Teaching In The Digital Age: Addressing Teachers’ Digital Competency, Blanca Nery Ibarra
Theses and Dissertations
The purpose of this study was to identify teachers’ digital skills proficiency gaps in order to determine preparedness for teaching in the digital age. Using a survey research design helped identify teachers’ digital skills self-confidence, attitudes towards the use of technology in the classroom, and current uses of technology for instructional purposes. The participants in this research study consisted of 320 middle school teachers from a border school district in south Texas. The data was collected using a survey instrument consisting of the TPSA C-21 and researcher-developed items. The data was analyzed using the Spearman-rank order correlation to describe the …
Breaking Bridges: A Latina's Role In Familismo And Higher Education, Desiree Trejo
Breaking Bridges: A Latina's Role In Familismo And Higher Education, Desiree Trejo
Theses and Dissertations
This research and collective experiences have been recorded to bring together an autoethnography that demonstrates my personal experiences of being the eldest daughter in a Latino family and how these experiences situate within a social context. The primary purpose of this autoethnography is to provide insight on Latino culture expectations placed upon first born daughters. My own experiences connect to my research covering Latino culture and gender expectations to further understand social meanings and understandings of this culture. This autoethnography presents qualitive research that allows me to self-reflect and apply these findings to my personal experiences within my family to …
Mitigate The Flood Risk At The Parking Lots At The University Of Texas Rio Grande Valley - Edinburg Campus, Mishell Carolina Mazon
Mitigate The Flood Risk At The Parking Lots At The University Of Texas Rio Grande Valley - Edinburg Campus, Mishell Carolina Mazon
Theses and Dissertations
This study focuses on the analysis of the drainage system in the parking lots of the Edinburg campus of the University of Texas Rio Grande Valley. The current project will use the rational method and modified rational method described in the Texas Department of Transportation manual to analyze and determine a solution for the current built drainage system. The primary objective of this study is to offer a practical and comprehensive solution to address the issue of this area that has flooded during heavy rainfall storm events. The proposed solution takes into consideration the building codes of the city of …
Organocatalyzed Four-Component On-Water Green Synthesis Of Spiroindolinpyranopyrazole, Tanzida Zubair
Organocatalyzed Four-Component On-Water Green Synthesis Of Spiroindolinpyranopyrazole, Tanzida Zubair
Theses and Dissertations
Although many synthetic and natural pharmaceuticals and drug-like compounds contain spiro center(s) in their structures, the synthesis of spiro centers is seen to be an exciting and difficult area of research. The synthesis of spiro compounds and their derivatives was carried out using a four-component process that included reagents like hydrazine hydrate, isatin, malononitrile, and an active methylene compound like ethyl acetoacetate. Microwave irradiation was used in a short time range (5 – 30 min) and moderate temperature (80°C), with water as a solvent, and N, N-Diisopropylethylamine (DIPEA) as a catalyst to give high yield of products. Our process complies …
The Effects Of Caffeine On Activity Levels And Motor Behaviors In The Honeybee, Apis Mellifera, Johana Castro
The Effects Of Caffeine On Activity Levels And Motor Behaviors In The Honeybee, Apis Mellifera, Johana Castro
Theses and Dissertations
Caffeine is produced by plants as a defense mechanism against herbivores and pathogens. However, caffeine was found in floral nectar, which contradicts nectar's role in attracting pollinators. Interestingly, low concentrations of caffeine were shown to increase alertness and locomotion in mammals and invertebrates, indicating it may enhance the productivity of pollinators. This investigation examined how caffeine affects activity levels and motor behaviors in the honey bee, Apis mellifera. To test overall activity, forager bees were collected and fed 1 M sucrose to satiation. The following day, bees received 10 µl of 1.0 M sucrose alone or with caffeine ranging from …
Latino Men’S Barriers And Obstacles Towards Treatment Seeking Attitudes, Rebecca Gonzalez
Latino Men’S Barriers And Obstacles Towards Treatment Seeking Attitudes, Rebecca Gonzalez
Theses and Dissertations
There is a drastic difference in the number of Latino men utilizing mental healthcare as only 24 percent of Latino men with a severe mental illness ever receive treatment. Previous research has revealed stigma and attitudes are important factors in the help seeking process, but with limited Latino participants. The current study gathered survey data from Latino male university students about their levels of stigma, attitudes towards both tele – health and in person counseling, perceived barriers and benefits, treatment history, and current levels of depression. It was revealed that in contrast to previous studies, Latino men’s social stigma is …
Machine Learning-Based Drone And Aerial Threat Detection For Increased Turret Gunner Survivability, Nikolas Koutsoubis
Machine Learning-Based Drone And Aerial Threat Detection For Increased Turret Gunner Survivability, Nikolas Koutsoubis
Theses and Dissertations
The introduction of aerial drones on the modern battlefield has transformed combat operations, posing a significant threat to ground-based military operations. Detecting drones in safety scenarios is crucial. However, modern machine learning (ML)-based object detectors struggle to detect small objects like drones. This thesis presents three main contributions: (a) data and algorithmic modifications to improve small object detection in YOLO to aid in drone detection, (b) the development of a benchmark drone detection dataset called DyViR, and (c) the implementation of explainable artificial intelligence (XAI) to ensure transparent and trustworthy decision-making. To boost the performance of small object detection, we …
Establishing Validity And Preliminary Clinical Utility Of A Behavioral Economic Measure Of Social Risk Discounting For Health Behaviors, Connor A. Burrows
Establishing Validity And Preliminary Clinical Utility Of A Behavioral Economic Measure Of Social Risk Discounting For Health Behaviors, Connor A. Burrows
Theses and Dissertations
The COVID-19 pandemic has been the most profound public health emergency of the past several decades and the United States has faced numerous challenges with the timely adoption of mitigating health behaviors. Sustained ambivalence surrounding perceptions of public health recommendations of social distancing, mask wearing, and timely vaccination remain a barrier to slowing the spread of the virus years after its initial onset. Behavior analysis and behavioral economics offer compelling theoretical and quantitative models for framing the relationship between behaviors that are aversive in the short term but beneficial for individual and public good in the long term. The present …
Securely Ever After: Attachment,Trust, And Commitment In Married Adult Adoptees, Jill P. Burgon
Securely Ever After: Attachment,Trust, And Commitment In Married Adult Adoptees, Jill P. Burgon
Theses and Dissertations
Past research suggests that adoptees face a higher risk of insecure attachment and encounter more challenges related to trust and commitment in their romantic relationships compared to nonadopted individuals. This study examines the association between adoption status and marital security among newly married couples, with a focus on the potential moderating role of gender. Using data from a representative sample of newly married couples in the United States (n = 2,110), the relationship between adoption status and multiple measures of marital security were measured using OLS regression. Findings indicate that, during the early stages of marriage, adult adoptees exhibited comparable …
Analyzing The Continuum Of Control And Freedom In Intimate Relationships: A Grounded Theory, Daniel Smedley
Analyzing The Continuum Of Control And Freedom In Intimate Relationships: A Grounded Theory, Daniel Smedley
Theses and Dissertations
Although research identifying and addressing extreme forms of control exists, all relationships experience some amount of control and some amount of the opposite of control, which is freedom. Large gaps in prevalence estimates and varied definitions of control suggest a need to better define the spectrum of control from mild to extreme forms, including looking at non-physically violent forms of coercive control. The purpose of this study was to expand knowledge of control in intimate relationships by examining the continuum of mild and extreme experiences of both control and freedom. Using constructivist grounded theory methods, the two categories of control …
Pillars Of Persistence: Factors That Influence Persistence Of First-Generation Students At 4-Year Public Institutions, Robert Stephen Wayland
Pillars Of Persistence: Factors That Influence Persistence Of First-Generation Students At 4-Year Public Institutions, Robert Stephen Wayland
Theses and Dissertations
In the past few decades, increased use of federal student loans has created an enormous financial burden for many first-generation and low-income students who attend 4-year public postsecondary institutions to attain a degree. Reaching those educational goals for many undergraduate students and how they reach their goals has been at the heart of much debate. The use of federal student loans and grants are paramount for many first-generation and low-income students in their pursuit of all benefits that accompany a postsecondary degree. There had been and will continue to be considerable consequences for the accumulation of debt through the use …
Investigation Of The Performance Of Anti-Corrosive Coating Materials Derived From Bio-Based Feedstocks, Sarah Anne Salazar
Investigation Of The Performance Of Anti-Corrosive Coating Materials Derived From Bio-Based Feedstocks, Sarah Anne Salazar
Theses and Dissertations
Corrosion is a costly phenomenon that is largely responsible for the deterioration of various infrastructures. While there are many corrosion prevention techniques, polymeric coatings are the most cost-effective and frequently used methods for protection of metal surfaces. The most commonly employed polymeric coatings are non-renewable BPA-based epoxide resins. Common curing agents are also the derivatives of hazardous amines such as ethylene di-amine and methylene dianiline. Therefore, there is a growing demand to develop renewable and less-harmful precursors from biomass to replace rapidly depleting petrochemicals. This thesis focuses on the characterization and optimization of anti-corrosive polymeric coating formulations derived from renewable …
Comparison Of Compact Very High Frequency (Vhf) Antennas For Small Airborne Ground Penetrating Radar, Tayler Austen Livingston
Comparison Of Compact Very High Frequency (Vhf) Antennas For Small Airborne Ground Penetrating Radar, Tayler Austen Livingston
Theses and Dissertations
UHF bands because more penetration can be achieved at low frequencies. Consequently, large antennas are required, which limits their use for small airborne applications. This thesis explores various GPR antenna designs for a bi-static system that are at least operational from 225 MHz to 255 MHz and suitable for small airborne applications. The 3D electromagnetic simulation software Ansys high-frequency structure simulator (HFSS) was used to simulate various sizes of strip dipole, triangular bowtie, half elliptical bowtie, and elliptical bowtie antennas. Several physical models were constructed to validate the return loss simulation results. Additionally, simulation data is included for a wire …