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Skeletal Age During Hurricane Impacts Fluctuating Asymmetry In Cayo Santiago Rhesus Macaques, Ashly N. Romero, Edwin Dickinson, Cassandra M. Turcotte, Claire E. Terhune Aug 2023

Skeletal Age During Hurricane Impacts Fluctuating Asymmetry In Cayo Santiago Rhesus Macaques, Ashly N. Romero, Edwin Dickinson, Cassandra M. Turcotte, Claire E. Terhune

Anthropology Faculty Publications and Presentations

As natural disasters become more frequent due to climate change, understanding the biological impact of these ecological catastrophes on wild populations becomes increasingly pertinent. Fluctuating asymmetry (FA), or random deviations from bilateral symmetry, is reflective of developmental instability and has long been positively associated with increases in environmental stress. This study investigates craniofacial FA in a population of free-ranging rhesus macaques (Macaca mulatta) that has experienced multiple Category 3 hurricanes since the colony's inception on Cayo Santiago, including 275 individuals from ages 9 months to 31 years (F = 154; M = 121). Using geometric morphometrics to quantify …


Estimation Of Gross Primary Productivity Of Rice In Arkansas Using The Vegetation Photosynthesis Model, Riasad Bin Mahbub Aug 2023

Estimation Of Gross Primary Productivity Of Rice In Arkansas Using The Vegetation Photosynthesis Model, Riasad Bin Mahbub

Graduate Theses and Dissertations

An estimate of the gross primary productivity (GPP) of rice fields can be instrumental to understand their harvest yield and to fulfill an array of agricultural monitoring needs. One of the most common satellite-based models to estimate GPP is the vegetation photosynthesis model (VPM). In this study, we use the VPM model for rice cropland in Arkansas and validate our findings against 16 site-years in-situ data (eddy covariance (EC)). At the site scale, results validated against 16 site-years have shown that the VPM with site information (R2 = 0.71, MAE = 2.90 g C m-2day- 1, and RMSE = 4.04 …


Raised Field Agriculture On The North Coast Of Peru: Environmental Investigations In The Casma Valley, Seth Price Aug 2023

Raised Field Agriculture On The North Coast Of Peru: Environmental Investigations In The Casma Valley, Seth Price

Graduate Theses and Dissertations

The Casma Valley, located on the central-northern coast of Peru, is home to a system of raised agricultural fields unique to the region. Relicts of pre-Hispanic culture, these fields are unusually well-preserved and primarily unaffected by modern agriculture. Multiscalar investigations of the Casma Valley raised fields revealed distinct anthropogenic soil alteration and landscape modification patterns. This dissertation assesses why Late Chimú (1300-1470 CE) societies in the Casma Valley converted ca. 2 km2 of land into raised agricultural field systems. This project is designed to investigate the composition and operation of raised fields, the short and long-term effects of field operation, …


Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed Aug 2023

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …


The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins Aug 2023

The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins

Graduate Theses and Dissertations

Zea mays is the most commonly grown grain in the world and is used for animal feed, human consumption, and the creation of other products such as ethanol and bioplastics. Contamination of stored maize with stored grain invaders can lead to loss of revenue, reduced food availability, and potential health complications. Two such storage invaders; the mold mite Tyrophagus putrescentiae and the fungus Aspergillus flavus can work as symbionts within the grain storage system. To determine resulting population growth from this symbiosis, maize was inoculated with three treatments: A. flavus with no mites, T. putrescentiae with no fungus, and both …


Development And Use Of A Detached Leaf Assay To Assess Soybean Cultivar Resistance To Target Spot, Caused By Corynespora Cassiicola, Rachael Wolf Aug 2023

Development And Use Of A Detached Leaf Assay To Assess Soybean Cultivar Resistance To Target Spot, Caused By Corynespora Cassiicola, Rachael Wolf

Graduate Theses and Dissertations

Target spot, caused by the fungus Corynespora cassiicola, was once considered a minor foliar disease of soybean in the US. However, a severe outbreak of target spot occurred in the southeastern U.S in 2016. Due to the lack of information on resistance in soybean cultivars, and the challenges in screening cultivars in the field, a detached leaf assay was developed to evaluate resistance. The objectives of the effort were to 1) develop a greenhouse inoculation method of soybean with C. cassiicola 2) use that method to compare reactions of soybean germplasm lines to target spot 3) collect and characterize isolates …


Toxicity Of Different Insecticides To Sitophilus Oryzae, Tribolium Castaeneum And Tribolium Confusum Infesting Corn, Amina Twaibu Aug 2023

Toxicity Of Different Insecticides To Sitophilus Oryzae, Tribolium Castaeneum And Tribolium Confusum Infesting Corn, Amina Twaibu

Graduate Theses and Dissertations

Corn is an important cereal crop cultivated across various countries, including the United States. Corn serves multiple purposes such as human and livestock food and raw material for industrial processes. Despite being an important crop, corn production faces challenges due to factors such as weather fluctuations and the presence of insect pests and diseases, both in the field and during storage. Among these challenges, insect infestation poses a major threat, as the insect damage not only reduces the quantity and quality of the grain but also renders it unfit for human and animal consumption, leading to a decrease in market …


The Effects Of Pesticide Exposure And Diet On The Health, Reproduction, And Behavior Of Mason Bees (Osmia Spp.), Olivia Mae Kline Aug 2023

The Effects Of Pesticide Exposure And Diet On The Health, Reproduction, And Behavior Of Mason Bees (Osmia Spp.), Olivia Mae Kline

Graduate Theses and Dissertations

Several mason bees (Osmia spp.), such as Osmia lignaria and Osmia cornifrons, are efficient and valuable pollinators in orchards. They can be used to supplement honey bee (Apis mellifera) pollination, to improve yields and reduce costs compared to A. mellifera alone. Osmia spp. encounter many stressors in their environment, which can negatively impact their health and pollination ability. These stressors include pesticide use and habitat loss due to agricultural expansion. Apis mellifera are often used as surrogates for pesticide risk assessment, but different bee species can vary widely in their response to stressors. Therefore, research into the impact of stressors …


Generation Z’S Perceptions Of Hunting And Conservation Efforts In Arkansas, Hannah Ferguson Aug 2023

Generation Z’S Perceptions Of Hunting And Conservation Efforts In Arkansas, Hannah Ferguson

Graduate Theses and Dissertations

Hunting participation numbers have steadily declined since the 1980s and Generation Z is not engaging in hunting. Hunting is one of the most effective tools for managing wildlife populations and ensuring the success and local ecosystem conservation. Many wildlife stewardship institutions, such as Arkansas Game and Fish Commission in Arkansas, are funded by sales taxes imposed on firearms, ammo, and archery equipment. With a decline in hunting participation, it is imperative state-run wildlife stewardship organizations and other hunting institutions learn the best practices for communicating with younger generations. This study sought to understand Generation Z’s perceptions of hunting and conservation …


Dietary Histidine: Broiler Responsiveness With And Without Endogenous Histidine Reserve Consideration, Kenneth Blake Nelson Aug 2023

Dietary Histidine: Broiler Responsiveness With And Without Endogenous Histidine Reserve Consideration, Kenneth Blake Nelson

Graduate Theses and Dissertations

In the past, histidine warranted little concern from poultry nutritionists because it was seldom deficient in practical broiler diets. With most essential amino acids now commercially available as feed-grade forms to partially replace intact protein ingredients, histidine and its minimum in least-cost formulation are receiving fresh attention. Published histidine requirement data for broilers are sparce, and many of these studies have been conducted on males within the first three weeks post-hatch. Moreover, rudimentary dose-response experimental designs may not be applicable to estimate histidine requirements in later growth periods because histidine is uniquely stored within the body. In times of dietary …


Density And Occupancy Of Mammals Along An Urban To Rural Gradient In Northwest Arkansas, Leah E. Mctigue Aug 2023

Density And Occupancy Of Mammals Along An Urban To Rural Gradient In Northwest Arkansas, Leah E. Mctigue

Graduate Theses and Dissertations

Human development is a rapidly expanding phenomenon impacting wildlife communities globally. As the human footprint expands, natural greenspace and nature reserves become fragmented and isolated. Wildlife species and communities respond to these changes in different ways. Urban exploiters persist in more urban areas and are able to take advantage of anthropogenic subsidies (food, shelter, etc). Urban avoiders, however, are species that may be pushed out of developed areas or occur in lower densities relative to undisturbed areas. Northwest Arkansas is an optimal location to study the impacts of urbanization on wildlife communities, as the current human population is expected to …


Shedding In The Timber Rattlesnake: Natural Patterns, Endocrinological Underpinnings, Temporal And Energetic Effort, And Integration As A Reptilian Life History Trait, Maxwell D. Carnes-Mason Aug 2023

Shedding In The Timber Rattlesnake: Natural Patterns, Endocrinological Underpinnings, Temporal And Energetic Effort, And Integration As A Reptilian Life History Trait, Maxwell D. Carnes-Mason

Graduate Theses and Dissertations

The semi-frequent replacement of the epidermis (ecdysis) is a characteristic trait of reptiles. Whereas all reptiles regularly engage in some degree of skin shedding, skin morphology in snakes necessitates the synchronous replacement of the entire epidermis and facilitates the subsequent removal of the old layer as a single sheet. To date, the ubiquitous process has garnered little attention from researchers because snakes shed with unpredictable timing and frequency and are exceedingly cryptic during ecdytic cycles; previously impeding detailed physiological or ecological investigations of the process in the clade. Because of the lack of study, ecdysis is often viewed as a …


Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino Aug 2023

Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino

Biological Sciences Undergraduate Honors Theses

This honors thesis aims to investigate the reusability and performance of cell coatings for cell therapy applications. Cell therapy, which involves the use of human cells to repair or replace damaged tissues, holds immense potential for medical advancements. However, ensuring the survival and functionality of transplanted cells remains a significant challenge. We focused on studying the effectiveness of coatings applied to cells for improved cell growth and viability. The research project involved the preparation of the coatings using a layer-by-layer method and the subsequent seeding of cells. The coated cells were then subjected to a series of experiments to assess …


The Influence Of Climate And Landscape On Allocapnia Mohri Distribution In Arkansas, Brianna Leigh Annaratone Aug 2023

The Influence Of Climate And Landscape On Allocapnia Mohri Distribution In Arkansas, Brianna Leigh Annaratone

Graduate Theses and Dissertations

Stoneflies are a globally threatened aquatic insect order. In Arkansas, a diverse group of winter stonefly (Capniidae: Allocapnia) have not been surveyed since the 1980s, likely because species-level identification requires the rarely-collected adult form. Allocapnia mohri, a regional endemic, was previously commonly found in mountainous, intermittent streams from the Ouachita Mountains ecoregion north to the Ozark Highlands, but no species distributional models including land use or climate variables exist to our knowledge. We collected adults from 70 stream reaches from the historic Arkansas range from November to April 2020 and 2021. We modeled distributions using random forest (RF) models populated …


Time And Chance Happen To Them All: A Macroevolutionary Examination Of The Effects Of Whole Genome Multiplications, Eric Robert Hagen Aug 2023

Time And Chance Happen To Them All: A Macroevolutionary Examination Of The Effects Of Whole Genome Multiplications, Eric Robert Hagen

Graduate Theses and Dissertations

Polyploidy, the state of having more than two complete sets of chromosomes, is common in plants and has been linked to several beneficial traits. On the macroevolutionary scale, the effects of polyploidy have been hotly debated for over one hundred years, being alternatively described as an “evolutionary dead end” and the most important discovery in evolutionary biology since Darwin and Wallace. This thesis aims to contribute to the debate by studying the diversification, biogeography, and ecophysiology of polyploid flowering plants with recently developed phylogenetic comparative methods. This dissertation has three chapters. In Chapter I, I review work on the so-called …


Modeling The Egyptian Goose (Alopochen Aegyptiaca) Invasion; And Future Concerns, Percival Matzinger Marshall Aug 2023

Modeling The Egyptian Goose (Alopochen Aegyptiaca) Invasion; And Future Concerns, Percival Matzinger Marshall

Graduate Theses and Dissertations

In an increasingly interconnected world, the ecological and financial cost of invasive species is expected to continue to climb through the movement of exotic biota. Understanding the driving forces behind how a species invades, what environments promote their establishment, and what impacts they are likely to have on the invaded environment are all critical for management. Waterfowl, order Anseriformes, are one such category of invasive species of concern due to their popularity of accidental introduction, ease of movement, and propensity to affect both terrestrial and aquatic ecosystems. The Egyptian Goose (Alopochen aegyptiaca) is a native to the African continent that …


Non-Energy Circular Economy Potential Of Rice Husks: A Techno-Eco-Environmental Assessment, Winfred Oppong Yeboah Aug 2023

Non-Energy Circular Economy Potential Of Rice Husks: A Techno-Eco-Environmental Assessment, Winfred Oppong Yeboah

Graduate Theses and Dissertations

The non-energy circular bioeconomy potential of rice husks was examined via sustainability assessments, namely life cycle assessment (LCA), life cycle impact cost assessment (LCICA), and techno-economic assessment (TEA). The study was conducted with three objectives. The first objective was to review previous studies on the non-energy utilization potential of rice husks by the method of meta-analysis. This review followed a systematic approach where research papers were collected following a defined set of criteria. The study revealed 16 key utilization pathways, all of which showed promising results. However, a comprehensive sustainability assessment was lacking in all of the pathways. The second …


Phenotypic And Transcriptomic Characterization Of Rice Snrk1 Mutants Developed By Crispr/Cas9 Mutagenesis, Maria Clara Faria Chaves Aug 2023

Phenotypic And Transcriptomic Characterization Of Rice Snrk1 Mutants Developed By Crispr/Cas9 Mutagenesis, Maria Clara Faria Chaves

Graduate Theses and Dissertations

SnRK1 is a heterotrimeric protein kinase that is composed of a catalytic subunit (α) and two regulatory subunits (β and βγ), and it has a main role in regulating energy homeostasis in the plant by modulating anabolic and catabolic process. SnRK1 phosphorylates and alters the activities of enzymes involved in metabolism and regulates gene expression by altering the activity of chromatin-remodeling enzymes or the transcription factors. Rice contains three functional paralogs of SnRK1α: SnRK1αa (LOC_Os03g17980), SnRK1αb (LOC_Os08g37800), and SnRK1αc (LOC_Os05g45420). This study focused on the function of these SnRK1 paralogs by evaluating the phenotypic and transcriptomic characteristics and the disease …


Treating High Salinity Produced Water Using Hybrid Membrane Processes: Electrocoagulation-Microfiltration/Ultrafiltration-Membrane Distillation-Crystallization, Mahmood Gheni Jebur Aug 2023

Treating High Salinity Produced Water Using Hybrid Membrane Processes: Electrocoagulation-Microfiltration/Ultrafiltration-Membrane Distillation-Crystallization, Mahmood Gheni Jebur

Graduate Theses and Dissertations

Produced water (PW) is considered the largest industrial wastewater stream in the world. PW generated from oil and gas operations generally contains a range of contaminants including high total dissolved solids, high total suspended solids, polar and nonpolar organic compounds, and low surface tension dissolved species. Treating PW is very challenging and applying only membrane-based technologies is not sufficient due to membrane fouling, which affects their long-term performance. Hence, integrated membrane processes are required to treat PW effectively. Hybrid membrane processes, which may result from combining a conventional process with a membrane separation, could be used to address the issues …


The Influence Of Temperature, Prey Availability, And Population Of Origin On Ectotherm Energetics, Allison R. Litmer Aug 2023

The Influence Of Temperature, Prey Availability, And Population Of Origin On Ectotherm Energetics, Allison R. Litmer

Graduate Theses and Dissertations

Climate change poses threats to organisms regarding direct and indirect effects of warming temperatures. Laboratory studies and predictive models are useful for understanding how temperature influences organisms, and the future of species’ life history and persistence. This dissertation expands upon current approaches to thermal studies and climate models, while investigating effects of warming nighttime temperature and altered prey availability on individuals and populations. Lizards in the genus Sceloporus were used as model organisms, as they are broadly distributed with thermally sensitive physiologies. The first dissertation chapter conducted meta-analyses to examine temperature-induced changes in food consumption, activity, and life history. Prominent …


Molecular Characterization Of Compartment Boundary Formation During Epithelial Remodeling In Drosophila Melanogaster, Samia Parveen Aug 2023

Molecular Characterization Of Compartment Boundary Formation During Epithelial Remodeling In Drosophila Melanogaster, Samia Parveen

Graduate Theses and Dissertations

The ability of epithelial cells to self-organize is crucial for the development of proper tissue structures and organs in multi-cellular organisms. Epithelia consist of inter-connected cells that form flat sheets, and specific groups of cells within these sheets are partitioned into distinct compartments via compartment boundaries (CBs). These CBs are specialized interfaces between cells characterized by stable, high-tension actomyosin cables, which act as fences to prevent movements between adjacent compartments during tissue reorganization. In the early Drosophila embryo, CBs are established in response to the asymmetrical localization of two cell-surface proteins the Leucine-Rich Repeat (LRR) protein Tartan and the Teneurin …


Juvenile Justice System Involvement And The Transition To Early Adulthood: Does Direct Intervention Help Or Harm?, Cameron Miller Perrine Aug 2023

Juvenile Justice System Involvement And The Transition To Early Adulthood: Does Direct Intervention Help Or Harm?, Cameron Miller Perrine

Graduate Theses and Dissertations

The present study examines the effects of the juvenile justice system on youth as they transition to early adulthood. The present study adds to the literature by incorporating comparison groups of youths and by testing multiple explanations of recidivism: Labeling Theory and the Life Course perspective. In total, 267 adults were recruited via online survey and sorted into three groups: Externalizing Behavior and Juvenile Justice Involved, Externalizing Behavior and Not Juvenile Justice Involved, and Not Externalizing and Not Juvenile Justice Involved. In addition to demographics, participants completed measures of past externalizing behaviors, past juvenile justice involvement, social disadvantage, deviant peer …


Injectable Immunomodulatory Strategies To Enhance Muscle Recovery Following Injury, Tai Huu Huynh Aug 2023

Injectable Immunomodulatory Strategies To Enhance Muscle Recovery Following Injury, Tai Huu Huynh

Graduate Theses and Dissertations

Although skeletal muscle displays an astonishing regenerative capacity, injuries or diseases that resulted in bedridden or chronic muscle wasting can overwhelm this intrinsic feature of skeletal muscle and lead to functional deficit (range of motion and/or strength) and overall reduction in quality of life. Microenvironmental cues within injured skeletal muscle dictate regenerative and repair process which are tightly coordinated interplay among resident cells, cells recruitment and immune response following an assault in the muscle extracellular matrix (ECM). The successful regeneration of functional tissues requires both appropriate modulation of the inflammatory response, and activation of a variety of cell populations. Biomaterials …


Rice Material State Diagrams: Trends Of Contemporary Cultivars And Influence Of Nitrogen Application During Production, Evans Ameyaw Owusu Aug 2023

Rice Material State Diagrams: Trends Of Contemporary Cultivars And Influence Of Nitrogen Application During Production, Evans Ameyaw Owusu

Graduate Theses and Dissertations

Rice is typically harvested at high moisture content (MC) levels which necessitates drying to low MC levels for safe storage. However, drying at inappropriate temperatures and durations can lead to deterioration of kernel quality such as fissure formation. Kernels with these fissures are typically associated with reduced head rice yields and significant economic losses. Material state diagrams for rice have been created by the University of Arkansas Rice Processing Program (UARPP) as a tool to aid in predicting the ideal temperatures to use during drying and tempering (a process of holding rice at the drying temperature for some duration). The …


Use Of X-Ray Imaging To Elucidate Impacts Of Drying Approach On Rice Seed Health, Samuel Olayiwola Olaoni Aug 2023

Use Of X-Ray Imaging To Elucidate Impacts Of Drying Approach On Rice Seed Health, Samuel Olayiwola Olaoni

Graduate Theses and Dissertations

Improper drying, which causes fissuring of rice kernels, may influence the overall seed health. This study evaluated the impacts of various drying conditions on rice fissures, seed germination and vigor. A long – grain rice cultivar with a moisture content (MC) of 15.5% w.b. (wet basis) was used during the experiments. Samples were dried as thin layers at temperatures of 30 ℃, 40 ℃ and 50 ℃ with a constant relative humidity (RH) of 50% and air velocities (AV) of 0.66 m/s and 1.65 m/s. X – ray imaging was used for fissure detection before and after drying the samples …


Functional Morphology Of The Platyrrhine Humerus And Talus: Implications For Inferring Locomotor Behavior In Extinct Primates, Liam Michael Zachary Aug 2023

Functional Morphology Of The Platyrrhine Humerus And Talus: Implications For Inferring Locomotor Behavior In Extinct Primates, Liam Michael Zachary

Graduate Theses and Dissertations

Platyrrhines are a diverse radiation of primates that exhibit a range of locomotor adaptations. The relationships between extant primate locomotor behavior and variation in postcranial morphology are often used to make functional interpretations of skeletal anatomy in extinct primates. However, a comparative baseline of form-function relationships in the extant platyrrhine postcranium is lacking compared to other primates, which limits understanding of platyrrhine locomotor evolution. The humerus and talus are two of the best represented skeletal elements in the platyrrhine fossil record and are informative of locomotor behavior. Therefore, quantification of morphological variation in extant platyrrhine tali and humeri can provide …


Securing Rice Safety Through Innovative Radiative Heat Treatment And Proper Storage, Faith Achieng Ouma Aug 2023

Securing Rice Safety Through Innovative Radiative Heat Treatment And Proper Storage, Faith Achieng Ouma

Graduate Theses and Dissertations

Securing the microbial safety of rice is a rising priority within the food industry, especially when used as an ingredient to manufacture ready-to-eat, minimally-processed products. Mold contamination is typically the most problematic for rice because certain species of Aspergillus produce toxic secondary metabolites known as aflatoxins, rendering the grain unfit for human and animal consumption. The objectives of this study are to: (1) investigate the effectiveness of using high-power (915 MHz frequency), short-duration microwaves (MWs) to inactivate microbes on rough rice; (2) use a three-level screening design to determine which storage factors, such as temperature, relative humidity (RH), storage duration, …


Next-Generation Nanopore Sensors Based On Conductive Pulse Sensing For Enhanced Detection Of Nanoparticles, Samuel Confederat, Seungheon Lee, Derr Vang, Dimitrios Soulias, Fabio Marcuccio, Timotheus I. Peace, Martin Andrew Edwards, Pietro Strobbia, Devleena Samanta, Christoph Wälti, Paolo Actis Aug 2023

Next-Generation Nanopore Sensors Based On Conductive Pulse Sensing For Enhanced Detection Of Nanoparticles, Samuel Confederat, Seungheon Lee, Derr Vang, Dimitrios Soulias, Fabio Marcuccio, Timotheus I. Peace, Martin Andrew Edwards, Pietro Strobbia, Devleena Samanta, Christoph Wälti, Paolo Actis

Chemistry & Biochemistry Faculty Publications and Presentations

Nanopore sensing has been successfully used to characterize biological molecules with single-molecule resolution based on the resistive pulse sensing approach. However, its use in nanoparticle characterization has been constrained by the need to tailor the nanopore aperture size to the size of the analyte, precluding the analysis of heterogeneous samples. Additionally, nanopore sensors often require the use of high salt concentrations to improve the signal-to-noise ratio, which further limits their ability to study a wide range of nanoparticles that are unstable at high ionic strength. Here, a new paradigm in nanopore research that takes advantage of a polymer electrolyte system …


B. R. Wells Arkansas Rice Research Studies 2022, J. Hardke, X. Sha, N. Bateman Aug 2023

B. R. Wells Arkansas Rice Research Studies 2022, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 50.1% of total U.S. rice production and 49.8% of the total acres planted to rice in 2022. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas that produce rice. Questions …


Bio-Methane Production From Anaerobic Co-Digestion Of Poultry Litter With Wheat Straw Improved By Process Optimization And Employment Of Advanced Techniques, Yuanhang Zhan Aug 2023

Bio-Methane Production From Anaerobic Co-Digestion Of Poultry Litter With Wheat Straw Improved By Process Optimization And Employment Of Advanced Techniques, Yuanhang Zhan

Graduate Theses and Dissertations

Anaerobic co-digestion (Co-AD) of poultry litter (PL) and wheat straw (WS) for sustainable waste management and simultaneously renewable bioenergy generation was improved by advanced technologies including micro-aeration (MA), biochar addition (BC), nanoparticles supplementation (NP) and their integrations. Response surface methodology (RSM) and artificial neural network (ANN) were used for the process modeling and optimization. First, a method by gradually increasing OLR was developed for the start-up of Co-AD of PL and WS in an anaerobic sequencing batch reactor (ASBR), with a continuous daily biogas production of (13.06 ± 0.21) L and methane content (MC) of (54.38 ± 0.53) % observed. …