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Forage Production and Nutritive Value of Leucanea leucoephala in Southern Puerto Rico
Get PDFLeucaena leucocephala (L.) is a perennial schrub native to Mexico, Central America and the Caribbean, considered by investigators as a valuable forage legume because of its capacity for high production of digestible forage with a high protein content and tolerance to drought in semiarid regions with annual rainfall less than 1,000 mm (Skerman, 1977). The soil fertility of the semiarid region in southern Puerto Rico is adequate, but rainfall distribution is limiting for forage production and nutritive value. There is a demand for a suitable and inexpensive source of high quality forage to improve the diet of the grazing cattle and to stimulate the development of the livesetock industry in the region. Therefore, research to investigate the potential use of perennial tropical legumes adapted to these environmental conditions and capable of sustaining a high quality forage production throughout the year is highly recommended. The objectives of the present investigation are to evaluate the forage production and nutritive value of Leucaena (L. leucocephala) in the semiarid region of southern Puerto Rico
The Curious Case of the Law Review Editor: A Study of Higher Education\u27s Peculiarly Powerful Students
Get PDFMany law students in their second or third year enroll in student-led, high-impact co-curricular programs such as law journals, moot court teams, and trial competition teams. Law journals particularly demand significant portions of students’ time and energy, especially for students holding Editor-in-Chief positions on a journal. Much has been written about law journals as institutions or about their utility in modern legal education; but little is known about the actual expectations and experiences of the students leading them. Few, if any, studies exist examining the student experience in law journal leadership. How student editors spend their time running their journal and what is expected of them by their peers, their institutions, and the scholars who publish with them is largely unexplored.
This qualitative study of several student editors of law journals seeks to fill this gap and answer the following research questions: In what ways do students benefit from participating in high impact practices like law journals? How are students selected to participate in high impact practices like law journals? What are the important factors influencing students to pursue a leadership position in a law journal? What is the experience like for those students in law journal leadership positions
Evaluating Preoperative Care Providers\u27 Perceptions of the Autism Support Checklist for Surgical Patients with Autism Spectrum Disorder
Get PDFAbstract
Background: Individuals with autism spectrum disorder (ASD) are more likely to report barriers to healthcare access than individuals with other disabilities and non-autistic persons. Many barriers to healthcare for those on the spectrum have been identified and include: negative interactions with healthcare staff, communication barriers with healthcare providers, lack of providers knowledgeable of ASD, sensory concerns, and difficulty navigating the healthcare system. The Autism Support Checklist (ASC) is a tool designed to outline communication methods, sensory concerns, soothing items/actions, triggers, special interests, safety concerns, and other information pertinent to an autistic patient. The tool is designed to convey the information necessary for healthcare providers to deliver patient centered care.
Purpose: The purpose of this DNP project was to evaluate the effect of utilizing the ASC on healthcare providers’ perceptions of supporting autistic patients in the preoperative (pre-op) setting. The specific aim of this project was to evaluate how healthcare providers perceive the effect the information conveyed in the ASC has on several aspects of care provided. These aspects of care include their ability to interact with, communicate with, and accommodate the sensory needs of autistic patients in the pre-op setting.
Methods: The project employed a quasi-experimental, post-test study design and included pre-op nursing staff which is comprised of nurses and nursing care technicians. The intervention involved providing a handoff of the information conveyed on the ASC to the assigned pre-op nursing staff. A post-test “ASC Provider Survey” was used to evaluate the impact of the intervention. Results: The ASC improved nursing staff perceptions of providing patient centered care for autistic patients in pre-op. Seventy-five percent of nursing staff in the pre-op department at University of Kentucky Chandler Hospital (UK Chandler) found the ASC easy to use and agreed or strongly agreed they were better able to communicate with and adjust the environment for the autistic patient based on information provided on the ASC.
Conclusion: The ASC could be a tool to improve pre-op nursing staff perceptions of providing patient specific, supportive care to autistic patients in the pre-op setting. The ASC could also be a springboard for further integration by expanding use of the tool to other areas within 2 perioperative services, UK Chandler at large, and/or, being the initial step to a greater autism friendly initiative by UK Chandler
SAFETY MONITORING & INTELLIGENT POWER DISTRIBUTION SYSTEMS FOR COMPACT AGRICULTURAL EQUIPMENT
Get PDFThe agricultural industry continues to be one of the most dangerous career fields in the United States of America with compact agricultural equipment being a common source for casualties in the industry. The primary focus of this work is to develop new technology that improves operational safety of compact agricultural equipment through the use of low-cost embedded electronics. This work presents the design of three systems in alignment with this goal.
The first system aims to integrate electrical intelligence and passive safety monitoring into the power distribution system of a small piece of agricultural equipment. The system known as the intelligent power distribution module introduces a microcontroller, an inertial measurement unit, electronic circuit control, supervised safety interlocks, current sensing, CAN communication, and data logging capabilities into the fuse block of the vehicle. A printed circuit board prototype of the system was designed and manufactured. In-lab performance and validation testing was conducted to prove the system concept as an effective safety-focused solution and identify areas of improvement.
The second system introduces a concept of scaling the accomplishments of the first system into a decentralized, modular package. A design for a distributed intelligent power distribution module which maintained power distribution, current monitoring, and data logging capabilities of original system while requiring a substantially smaller physical footprint was presented. A prototype of the system was produced and validation testing in a lab setting was conducted. Testing results validated the concept as a feasible method implementing the successes of the original intelligent power distribution module in distributed manner while also revealing areas for improvement in future iterations.
Finally, the third system provides the foundation for orientation monitoring of compact agricultural equipment through the use of low-cost inertial measurement units. Two variations of the system were developed, and multiple rounds of testing were conducted to validate the feasibility of the system as well as continually refine the orientation estimation algorithm of the system. Statistical analysis of the final testing results provided validation of the concept while also highlighting necessary improvements to calibration methodology and system architecture to improve system reliability and performance
MEASURING ACCESSIBILITY OF ELECTRIC VEHICLE CHARGING INFRASTRUCTURE: A CASE STUDY IN KENTUCKY
No full textThis thesis assesses spatial accessibility to electric vehicle charging infrastructure across Kentucky by investigating methodological approaches to measure accessibility: provider-topopulation ratios, regional accessibility metrics, and several methods in the family of gravity models. The Enhanced Two-Step Floating Catchment Area method was employed to measure electric vehicle charging station accessibility across Kentucky using a network-based approach in ArcGIS Pro. The analysis integrated 2023 American Community Survey 5-year Census block group data, Kentucky road network datasets, charging station locations from the Alternative Fuels Data Center, and Alternative Fuel Corridor designations. We examined existing infrastructure and proposed stations outlined in the Kentucky electric vehicle charging plan, and Spatial accessibility indices were calculated for all census block groups. This research also assessed the accessibility of electric vehicle charging stations across household income categories. To identify underserved areas, spatial accessibility maps were overlaid with the Alternative Fuel Corridor network. Results indicate increased accessibility in urban centers such as Lexington and Louisville, while rural regions—especially Eastern Kentucky and growth corridors like the Audubon Parkway—continue to face charging infrastructure gaps. Shortage areas along major highways are identified for additional charging infrastructure deployment if the opportunity arises. This research identifies ongoing challenges to the reconciliation of infrastructure development with geospatial and socioeconomic needs. With the addition of advanced methodologies to geospatial analysis, the study furnishes a data-driven framework to analyze the accessibility of electric vehicle charging stations and to inform planning of future EV charging infrastructure in the state
TARGETED MITIGATION STRATEGIES TO REDUCE SECONDARY EMISSIONS IN CO2 CAPTURE SYSTEMS
No full textGlobal CO2 emissions from industrial, power generation and transportation sources has led to the call for increased implementation of carbon capture strategies. The most developed of these is point source carbon capture, which refers to the process of capturing CO2 directly from large (point) source emitters, before the CO₂ is released into the atmosphere. The challenge becomes separating CO2 from the other components of the emitted gas, mainly nitrogen. These CO2 capture processes typically involve the use of aqueous solutions of amines to absorb (capture) CO₂ from the gas stream, where the CO2 and the basic amine in water react to form a carbamate or bicarbonate depending on the specific amine used. One clear advantage when using amine solutions is that this reaction is reversible, as the absorbed CO2 is released when the solution is heated allowing the amine to be reused in multiple cycles of absorption and regeneration.
This type of amine-based carbon capture is not without some drawbacks. The temperature swings needed for this desorption process not only requires significant energy input but can also lead to gradual degradation of the amine, commonly referred to as thermal degradation. This can lead to solvent losses, reduced performance, and higher operational costs. In addition, the solvent can also degrade due to exposure to oxygen and other contaminants present in combustion flue gas (such as SO₂, NOx). This oxidative degradation can lead to the formation of unwanted byproducts, some of which are regulated volatile organic compounds. Amine degradation can produce a combination of different species generating a complex matrix that when coupled with the high pH environment, can make degradation remediation challenging. To avoid unintended environmental effects, the amine degradation pathways need to be carefully understood and managed. This dissertation focuses on understanding the degradation by-products of amine solvents in carbon capture systems and how the chemical differences between the amine and water impacts the volatility and the removal of these degradation compounds. A better understanding of theses impacts allows for the development of mitigation strategies minimizing any environmental impacts.
Mitigation of the unwanted degradation byproducts is achieved by either removing the contaminants from the solvent or capturing and neutralizing them within the system. First, an assessment was performed to understand the effectiveness of solvent degradation mitigation using activated carbon adsorption, with implications for treating high pH solutions. While there were some benefits to this methodology, activated carbon adsorption was not completely effective and presented several limitations such as metal leaching from the activated carbon material. Given this, it is necessary to expand into other techniques for degradation mitigation. First a better understanding the potential for emissions of any degradation products, including compounds such as aldehydes, is crucial given their known environmental and human health hazards. These emissions may be impacted by the composition of the amine solvent used, therefore the Henry’s volatility coefficient of acetaldehyde in relevant amine solutions were determined as a surrogate for other classes of potential degradation compounds. The volatility was determined to be significantly higher from the amine solvent when compared to water, which is critical fundamental information in aiding the development of proper mitigation strategies that can be implemented within capture systems.
Current engineering controls within CO2 capture plants involve the use of waterwash systems to reduce amine emissions, however some degradation products are also captured by this system which allows for their targeted neutralization. The composition of the wash-water poses yet another unique challenge as the complex matrix and increased the pH make it difficult to treat via traditional water treatment methods. An electrochemical-mediated treatment method was developed and evaluated to facilitate the decomposition of N-nitrosamines and aldehydes. The experimental results showed that even in the presence of this complex matrix, highly efficient decomposition of these hazardous compounds can be achieved
CATALYTIC DEOXYGENATION OF OLEAGINOUS BIOMASS TO RENEWABLE DIESEL AND SUSTAINABLE AVIATION FUEL VIA DECARBOXYLATION/DECARBONYLATION
Get PDFSeveral technologies have been developed to produce hydrocarbon biofuels – renewable diesel (RD) and sustainable aviation fuel (SAF) – from fats, oils, and greases (FOG), with the hydroprocessing of esters and fatty acids (HEFA) representing one of the most mature pathways. In its current form, HEFA is mainly reliant on the hydrodeoxygenation (HDO) reaction, which has several drawbacks since HDO requires large amounts and pressures of hydrogen, feedstocks of high purity and cost, as well as problematic sulfided catalysts that risk contaminating the biofuel product with sulfur. A process based on decarboxylation/decarbonylation (deCOx) offers an attractive alternative to HDO, since it requires lower amounts and pressures of hydrogen, feedstocks of low purity and cost, and simple supported metal catalysts. Herein, several geographically distributed oleaginous feedstocks – ranging from municipal waste feeds (brown grease) to pine chemicals (tall oil and rosin) – were upgraded to RD and SAF via deCOx. Powdered and engineered Ni-based catalysts were used for FOG-to-RD conversion via deCOx, evaluating deoxygenation over reducible and non-reducible oxides. An engineered alumina-based catalyst showed superior deoxygenation activity and stability for up to 300 hours on stream. Similarly, quantitative conversion of FOG to SAF was achieved over bifunctional Ni-Cu-based catalysts with zeolitic support, with deCOx and isomerization occurring in a single step. Initial screening studies performed in a semi-batch reactor revealed that upgrading distilled tall oil (DTO) over a Ni-Cu-based catalyst afforded all types of hydrocarbons comprising SAF, namely, n-alkanes, iso-alkanes, cycloalkanes, and aromatics. The same combination of feed, catalyst, and reaction conditions were applied in a fixed-bed reactor for a continuous experiment, consisting of two 72-hour cycles with a catalyst regeneration in between. DTO conversion remained quantitative (~100%), with aromatic yields ≥80% regardless of time-on-stream. Most liquid products fell within the carbon number and boiling point range of jet fuel across all samples. Notably, the reaction produced all hydrocarbon classes found in SAF, with particular abundance of aromatic hydrocarbons. Since ~20% aromatics are required to swell elastomeric seals and prevent leaks in aircraft fuel systems, seal compatibility testing confirmed that the aromatics-rich SAF blendstock exhibited a volume swell percentage comparable to qualified SAF blends. Catalysts used for deoxygenation reactions were characterized using various techniques – including N2 physisorption, X-ray diffraction, X-ray photoelectron spectroscopy, microscopy, and temperature-programmed methods – to rationalize trends, propose reaction pathways, and elucidate structure-activity relationships. Finally, to evaluate the economic and environmental feasibility of this technology, techno-economic and lifecycle analyses were conducted on an integrated plant combining catalytic deoxygenation and hydrothermal gasification, producing hydrogen for converting tall oil fatty acid to SAF. The analyses revealed a minimum fuel-selling price of USD1.4/L) – with greenhouse gas emissions of 5.1g CO2-eq/MJ, which is 94% lower than fossil jet fuel (85g CO2-eq/MJ)
SPECIAL EDUCATOR PERSISTENCE: UNVEILING TEACHER PERCEPTIONS
Get PDFThere is a continually growing shortage of special education teachers (SET). The shortage is so dire that the U.S. Bureau of Labor Statistics (2024) anticipates that as many as 35,900 new SET will be needed each year for the next decade. One of the leading factors contributing to the shortage of special educators is attrition, or any loss of teachers from their positions (Darling-Hammond, 2003; Ingersoll, 2001). Teacher persistence, therefore, is a critical concern in addressing the teacher shortage. The purpose of this mixed-methods research study is to examine the association between previously identified factors of attrition and SET decisions to remain in the profession. The study also seeks to contribute to the research by understanding how SET perceive the impact of the post-pandemic landscape on their teaching experience and decisions regarding persistence.
Data from a self-report perception questionnaire were analyzed using Pearson’s correlation coefficient to determine any significant findings. Once the data were analyzed, semi-structured interviews were conducted to collect additional data regarding SET perceptions relating to their decisions to remain in the profession
Mathematical-Programming Modeling of Power-Electronics-Based Microgrid Systems
Get PDFThe emergence of power-electronics-based microgrid systems is driven by the shift to cleaner energy, transportation electrification, renewable integration, grid modernization through smart grid advancements, and growing demand for energy-efficient solutions. For utilities, these systems present unique opportunities for enhancing grid resilience, improving load management, and enabling distributed energy resource integration. This work presents a modeling and simulation approach for microgrid systems that uses mathematical programming to represent power flow and capture the system dynamics. By solving an optimization problem at each time step, the method enables evaluation of power distribution and system performance under a range of operating conditions, without requiring detailed component-level specifications. This work introduces a baseline Mathematical Programming Approach (MPA), which assumes an idealized omniscient controller, and an extended Controller-Augmented MPA (CMPA), which explicitly incorporates the behavior of practical controllers. While MPA is valuable for early-stage design studies by offering insight into optimal operation and system limitation, it overlooks the influence of suboptimal control logic and uncertainty. CMPA addresses this by decoupling controller behavior from physical system dynamics, enabling more realistic modeling of power-electronics-based systems. Together, these approaches provide a versatile framework for researchers and utilities to evaluate microgrid architectures, explore control strategies, and assess system resilience
PAUL BOWLES’ \u3ci\u3e BLUE MOUNTAIN BALLADS \u3c/i\u3e FOR WIND OCTET AND SOLO VOICE: A TRANSCRIPTION OF A SONG CYCLE USING THE INSTRUMENTATION OF STRAVINSKY’S \u3ci\u3e OCTET \u3c/i\u3e
Get PDFBlue Mountain Ballads (1946), by Paul Bowles, is a song-cycle and setting of four poems by Tennessee Williams who was the composer\u27s friend and mentor. The work has long held a place in the vocal repertoire. Bowles’ unique harmonic language, wide accompanimental range and the use of jazz idiom provide a unique opportunity for the music to be re-cast for wind instruments. Furthermore, chamber music makes up most of Bowles’ musical output as a composer, so using small instrumental forces seemed an appropriate medium to re-orchestrate this song cycle.
The purpose of this document is 1) to provide a detailed analysis of each of the songs within the cycle; 2) to provide a detailed account of the transcription process and justification to support the use of Stravinsky’s instrumentation as the orchestrational palette for the transcription; 3) to provide a detailed conductor’s guide for performance of this work as a companion to Stravinsky’s Octet OR as a standalone work for voice and chamber winds.
The first chapter of this document will provide a brief biography of Paul Bowles and highlight his relationship with Tennessee Williams and thus the origins of the composition as well as an overview of some of his compositional output. Chapters two will provide a brief overview of the entire work. Chapters three detailed analysis of each of the songs in their performance order: “Heavenly Grass,” “Lonesome Man,” “Cabin,” “Sugar in the Cane.” Chapter four will provide a justification for why this piece was well suited for transcription, its inclusion in the chamber winds repertoire, and the considerations made throughout the transcription process while using the Stravinsky’s original instrumentation. Chapter five will provide a brief conductor’s guide and discuss programming and performance considerations The appendix will include the complete score for Blue Mountain Ballads for Wind Octet