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Inducing Potential Mutants in Industrial Hemp (Cannabis sativa L.) via Physical and Chemical Mutagenesis
No full textCannabis sativa is a multi-use crop with applications in food, fiber, construction, and medicinal industries. Cannabis plants with low THC concentrations (hemp) have recently been decriminalized by multiple nations across the globe, but farmers are still on the fence about its legality. To avert the risk and constant regulatory pressures due to potential THC contents, we aim to develop a Cannabis variety with zero cannabinoids - Type V Cannabis, using physical and chemical mutagenesis. We selected EMS as the chemical mutagen and E-beam radiation as the physical mutagen and identified the LD50 doses for three hemp varieties ��� HT, 4X, and HCP. The variations in seed germination percentages among mutagen treatments were found to be highly significant (P < 0.05). The M0 seeds were treated with the LD50 dosage of the mutagen to produce mutant M1 populations. The M1 plants displayed a wide array of mutant phenotypes and were tested for their trichome profiles. Selection of M1 plants was done based on mutant phenotypic traits and trichome production, followed by self-hybridizations to produce M2 seeds. The obtained line- Type V is expected to be 100% compliant with all regulations. This promising line presents a new, versatile, and sustainable crop with applications in food, fiber, and construction industries, addressing the growing needs of the nation
Can Tariffs Benefit Our Nation?
No full textWhen can adopting tariffs increase a country's welfare? In this policy paper, PERC Fellow Amy Glass discusses the conditions needed for a large country to achieve an optimum tariff, terms of trade, and changes in price due to tariffs. Trade war effects and shifts in production due to tariff avoidance are also discussed
Using Antibiotic Alternative Feed Additives to Improve Overall Duck Growth Performance and Welfare
No full textGrowing ducks with optimal efficiency, health, and welfare has become of paramount importance. While numerous antibiotic alternatives (AA) have been investigated in other poultry species to reach these goals, there has been limited research on Pekin ducks. Several experiments were conducted to determine the effects including (i) organic acids (OA), (ii) oregano oils (OO), and (iii) direct fed microbials (DFM) in ducks. Experiment 1 evaluated duck growth, health, and welfare with water supplementation of OA and OO. The OA and OO improved feed conversion ratio (FCR) and body weight (BW) (P 0.05). Experiment 2 evaluated optimum inclusion rates of a commercially available (DFM) feed additive. Duck growth, stress, fear response, welfare, and litter conditions were evaluated. Results conveyed CON had higher (P 0.05) compared to CON. Experiment 3 evaluated the use of the same treatments as Experiment 2 except for the addition of a prolonged heat stress period added during the grow out. Results indicated BW and FCR compared to CON (P > 0.05) was higher than all other treatments. Total white blood cell counts were lower than CON (P < 0.05) compared to all other treatments in the DFM heat stress trial. Heterophil counts, H/L ratio, and total plasma corticosterone levels were also lower than CON (P < 0.05) compared to all other treatments reviewed whether through water supplementation or dietary supplementation. Lymphocytes counts were higher than CON (P < 0.05) compared to all other treatments. Villus height presented differences (P < 0.05) in all other treatments compared to CON. In conclusion, these experiments indicate that Organic Acid, Oregano Oils, and Direct fed microbials can be used to improve duck growth, feed efficiency, stress susceptibility, and bird welfare
A Guarantee for Confusion: The Impact of Texas��� Guaranteed Tuition Legislation on Tuition and Fees
No full textIncreases in tuition and fees annually charged to students have resulted in public universities and colleges under scrutiny from state legislators. There are as many approaches to increases in tuition as there are states. States like Texas, Illinois, and Oklahoma have implemented legislation requiring public institutions in their respective states to freeze tuition for students. Unlike other states, Texas has placed the requirement on institutions vs. a requirement placed upon students. This research examines the impact on average tuition and average enrollment for Texas public four-year institutions subjected to that state���s guaranteed tuition legislation, using difference-in-differences, a quasi-experimental method. Panel data from 2008 to 2019 obtained from 531 public four-year universities in the United States via the Integrated Postsecondary Education Data System (IPEDS) were used to address two research questions: (1) At public four-year institutions, does the implementation of a required state-level guaranteed tuition policy option for students lead to changes in annual tuition charges of the aggregate amount of tuition paid by students over four years? (2) At public four-year institutions, does the implementation of a state-level guaranteed tuition policy option lead to changes in enrollment for students?
The analysis found the Texas legislation did not significantly increase the average annual tuition charged to in-state students. On average, the legislation did result in a .96 decrease in the average required fees. The analysis also found there were positive changes in enrollment after the imposition of the guaranteed tuition plan legislation. The findings of this study provide insight into the consequences associated Texas��� guaranteed tuition plan legislation. For state policymakers, this study suggests the way in which a guaranteed tuition plan is structured is impactful. For institutional leadership, this study suggests room for improvement in how these plans are described and marketed to students and their families
Applied and Theoretical Approaches to Decision Making in Agriculture
No full textThis work consists of three essays, each demonstrating economic approaches to decision making.
In the first essay, the choice of which Title I farm program to enroll in is modelled as a quadratic integer programming problem. This framework is used to determine optimum program selection for upland cotton producers in Hale County Texas with average risk aversion.
The second essay quantifies the gains in efficiency resulting from recent infrastructure development in the Southern Plains region of Texas. The transportation of agricultural commodities on public roads imposes a number of costs on the state. These include increased road maintenance, ecological damage and traffic congestion in urban centers. The presence of these externalities can lead to inefficient market outcomes. This paper uses a linear programming model to study recent changes to the supply chain of cottonseed and lint and the associated improvement in efficiency.
The third essay is a theoretical piece that expands traditional consumer theory, allowing it to be used in new contexts. It uses this framework to explore and reconcile opposing viewpoints on the value of work. It demonstrates that the process of producing commodities is a potentially important source of utility and failing to account for this results in a misleading evaluation of welfare changes associated with a modification of manufacturing methods
Optimizing Produced Water Treatment in the Permian Basin: The Role of Indirect Evaporative Cooling in Hydraulic Fracturing
No full textThis study investigates the novel application of Indirect Evaporative Cooling (IEC) for treating produced water in hydraulic fracturing operations within the Permian Basin. Utilizing a lab-scale IEC system, we conducted fifteen experiments to assess Total Dissolved Solids (TDS) and volume reduction in produced water, considering variations in initial water volume, composition, and TDS concentration. The experiments included a range of synthetic samples with salinities from 0 to 70,000 ppm and real-produced water from different Permian Basin regions (Delaware, North Midland, and South Midland).
Our findings reveal that IEC's efficiency in TDS removal, achieving near 100% effectiveness for both synthetic and real produced water samples, is primarily influenced by the presence of the most abundant salts rather than the overall TDS concentration. This highlights the system's capability to handle high salinity and diverse impurities typical in oil and gas production waters. Additionally, the IEC system proved to be significantly less energy-intensive compared to traditional thermal evaporation methods.
The economic assessment of IEC versus standard evaporation methods for treating one barrel of water further demonstrates its viability. The study concludes that IEC offers a highly effective, environmentally sustainable, and economically feasible solution for high TDS oil field water treatment. It stands out as a promising alternative to conventional technologies, with potential applications extending across various industrial facilities. This research paves the way for future exploration to maximize the potential of IEC in addressing the wastewater challenges in hydraulic fracturing
Enhance PET Degrading Enzyme Performance Through Immobilization on Magnetic Nanoparticles
No full textGlobal plastic generation has reached 460 million tons in 2019 of which 353 million tons ended up as waste. PET is a widely generated and consumed thermoplastic due to its mechanical and chemical properties. It makes up to 67% of the packaging plastic. Due to its resistance to chemical and mechanical changes it becomes a challenge to handle PET waste. PET requires harsh conditions to decompose into its monomers of TPA and EG. Efforts have been made to recycle PET by degrading it to its monomers or reshaping and upcycling it from there.
Currently, the three major ways of recycling PET comprise of chemical recycling, mechanical recycling and using biological systems for recycling. Chemical recycling of PET is achieved through solvolysis and pyrolysis which is accompanied by release of toxins in the atmosphere. Mechanical recycling does not break down PET to its monomers but reshapes the PET so it can be reused. However, this only recycles PET to a certain extent, after which it can no longer be reshaped and reused since it loses mechanical strength. Biodegradation has become an attractive alternative to chemical and mechanical recycling due to its cost-effectiveness and milder reaction conditions, which makes it a more environment-friendly approach.
The major challenge that comes with biodegradation is the aggregation of the enzymes at higher concentration which inhibits the enzyme activity. To overcome this challenge, there have been attempts to immobilize the enzymes on scaffolds which provides an even distribution and prevents aggregation. With PET degrading enzymes, there have been attempts to immobilize PETase on nanoparticles previously which enhanced the activity of the enzyme. However, none of the existing systems could achieve complete depolymerization of PET. We have proposed a method to immobilize both PET degrading enzymes, FAST PETase and MHETase on iron oxide nanoparticles to enhance activity and achieve complete depolymerization of PET. In addition to this, we also incorporated a carbohydrate binding module (CBM) into the system which has shown to enhance activity by helping the enzyme come in closer proximity to the substrate.
It has been observed that even a small amount of MHETase boosts the PET degradation and the limiting step in conversion of PET to MHET is PETase. We found that 1:20 ratio of pure MHETase to FAST PETase is the optimum ratio for PET degradation. To achieve this ratio on the nanoparticles, we tried sequential addition and compared it with simultaneous addition. The sequential addition helped increase the amount of MHETase immobilized and the total enzyme loading. This two-enzyme system on nanoparticles showed a 2.5-fold increase in TPA release compared with the free enzyme system. We were able to show reusability of the bioconjugates using simple magnetic separation. The enzyme bioconjugates also showed higher stability when stored at 4��� as compared to free enzyme.
With CBM, the enzyme did show higher activity than the samples without CBM initially, however during the course of the assay, it did not show as much enhancement towards the end. This could be due to product accumulation in close proximity of the enzyme which inhibits the activity thereafter. The system could still be optimized further for shorter duration of assays.
With the current system consisting of FAST PETase and MHETase on iron oxide nanoparticles, we were able to achieve complete depolymerization of PET with additional advantages of reusability and enhanced stability through immobilization on nanoparticles. The knowledge from this work could guide other multi-enzyme systems with non-equimolar requirement to enhance activity through immobilization
Centering Cemeteries in Environmental Justice: Observing Community Connectivity in Historic Texas Black Cemeteries
No full textThis research seeks to create new knowledge on Black cemeteries by employing methodologies that are innovative within the field of urban planning. Drawing from concepts borrowed from Black Geographies and Anthropology, particularly Participatory Geographic Information Systems (PGIS) methods, this study aims to delve into the intricate dynamics and significance of Black cemeteries within their respective communities. The significance of Black cemeteries transcends their role as mere burial sites; they serve as crucial spaces for memorialization, historic preservation, and community cohesion. Over generations, these cemeteries have acted as repositories of collective memory, fostering a sense of continuity, and belonging among community members. Moreover, they function as dynamic hubs of activity, where rituals, events, and ongoing preservation efforts contribute to the creation of a shared sense of space and identity. Furthermore, the interconnectedness of Black cemeteries unveils a broader network of stewards and community members dedicated to place-making and heritage preservation. These networks facilitate land-use planning and address environmental justice issues by promoting resource sharing and skill exchange among communities. This research highlights the relevance of local histories and the engagement of local stewards in the preservation and management of Black cemeteries. However, the primary contribution lies in the incorporation of local knowledge into urban planning practices related to cemetery management. It emphasizes the importance of recognizing and valuing the intrinsic significance of these cemeteries within the context of environmental justice movements. In conclusion, safeguarding and advocating for the preservation of Black cemeteries is not merely an act of historical conservation but a fundamental aspect of social and environmental justice efforts. The utilization of geo-humanities as a tool in this research allows for a nuanced understanding of memorialization, place-making, visibility, accessibility, and vulnerability at the granular level, as evidenced through two case studies
Semi-Synthetic Analogs of Occidiofungin
No full textFungal infections are a global healthcare concern. Multi-drug resistant fungal infections present a great challenge for the treatment of infected individuals. Current classes of antifungal agents each have their own limitations. The last class of antifungal agent approved for treating systemic fungal infection was echinocandins in the early 2000s. Occidiofungin is a natural product produced by the soil bacterium Burkholderia contaminans MS14. The structure is a cyclic glycolipopeptide consisting of 8 animo acids. The mechanism of action of occidiofungin is unique compared to current antifungal agents. Murine models demonstrated that occidiofungin had minimal toxicity and was effective in treating vulvovaginal candidiasis. Occidiofungin is currently in phase 1 clinical trials for the treatment of recurrent vulvovaginal candidiasis. This dissertation is focused on the characterization of novel occidiofungin variants, and the production and characterization of semi-synthetic occidiofungin analogs. Semi-synthetic occidiofungin analogs were produced by modifying the sidechain of novel amino acid 2. These analogs were used to investigate the structure-activity relationship of occidiofungin. The diol group on novel amino acid 2 plays an important role in the antifungal activity of occidiofungin, likely contributing to cellular uptake. A newly identified occidiofungin variant was identified which contains aspartic acid instead of asparagine at position 7. The aspartic acid variant could be utilized to produce semi-synthetic analogs by targeting the terminal carboxylic acid on the aspartic acid. The aspartic acid residue presents a region that is highly amenable to modification without reducing antifungal activity. A phosphate prodrug semi-synthetic analog designed to treat systemic infection has been developed. Occidiofungin was not able to reduce the fungal load in a systemic candidiasis murine model, which may be due to high levels of binding to serum proteins. The phosphate prodrug analog demonstrated in vitro antifungal activity and reduced binding to serum proteins. Future investigation into the efficacy of the phosphate prodrug analog in treating systemic fungal infections will be performed
Pair Production in Strong Fields
No full textThe correction to the Coulomb energy due to virtual production of e+e��� pairs, which is on the order of one percent of the Coulomb energy at nuclear scales, is discussed. The effects of including a pair-production term in the semi-empirical mass formula and the correction to the Coulomb barrier for a handful of nuclear collisions using the Bass and Coulomb potentials are studied. With an eye toward future work using Constrained Molecular Dynamics (CoMD) model, we also calculate the correction to the Coulomb energy and force between protons after folding with a Gaussian spatial distribution.
In the collision of two heavy ions the strong repulsion coming from the Coulomb field is enough to produce real e+e��� pair(s) from vacuum fluctuations. The energy is provided by the kinetic energy of the ions and the Coulomb interaction at the production point. If, for instance the electron is located at the center of mass (C.M.) of the two ions moving along the z-axis, and the positron at a distance x from the electron, the ions can be accelerated towards each other since the Coulomb barrier is lowered by the presence of the electron. This screening results in the increase of the kinetic energy of the colliding ions and may result in an increase of the fusion probability of light ions above the adiabatic limit.
Nuclear scattering is not the only situation where real pairs can be produced by this mechanism. In particular, the fields involved in �� decay and nuclear fission are strong enough to produce pairs. The energy of the e+e��� pair is related to the relative distance and velocity of the daughter nuclei. Thus, the energy distribution of the produced pairs can give information about the dynamics of the fission and �� decay processes. A neck model of nuclear fission is used to illustrate how the pairs can be used as a probe of the dynamics.
This model of pair production is also applied to situations with strong fields involving lasers. In particular, lasers can fully ionize clusters of atoms, which then expand in a ���Coulomb explosion," and when a laser irradiates the surface of a metal, a shower of protons is ejected in a phenomenon known as Target Normal Sheath Acceleration (TNSA). The fields involved in these cases were found to be too weak to produce pairs with this mechanism. Likewise, no pairs are produced by the gravitational field at the event horizon of a black hole, indicating that this mechanism is different from Hawking radiation