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Effect of Traditional Versus Fenceline Weaning on Lamb Stress
No full textStress in sheep can negatively affect productivity and increase their susceptibility to illness and parasites. The traditional method of weaning lambs is the abrupt separation of lambs from their dams. An alternative method of weaning, fenceline weaning, where offspring are separated from their dams by a single fence but retain visual and auditory contact, has been found to reduce stress in cattle and may also reduce stress in sheep. The objectives of this study were to evaluate body weights, fecal egg counts, and behavior to determine if traditional or fenceline weaning has lower stress associated with weaning in lambs. The study was conducted at the University of Arkansas System Division of Agriculture\u27s Milo J. Shult Agricultural Research & Extension Center, with two 14-day trials, totaling 32 majority Hampshire lambs (23.5± 0.91 kg initial body weight). Lambs were assigned to either the fenceline or abrupt weaning group. Behavioral responses were observed through video recordings using instantaneous scan sampling for the first three days after weaning. Fecal egg counts (day 14) and weight change measurements (day 0 to 14) were not different (P ≥ 0.26) between the weaning methods. The interaction between weaning group and day was detected for lying and eating behaviors (P ≤ 0.02). The lambs in the fenceline weaning group performed walking behaviors less frequently than the abrupt weaning group. Therefore, fenceline-weaned lambs appeared to have less stress than the abruptly separated weaned lambs. However, further investigations should be conducted to determine the long-term impacts of weaning strategies
Escape from the Floating World : Kabuki Theater in Conflict with the Bakufu Government of Tokugawa Japan (1600-1868)
No full textUkiyo 浮世, the “floating world” of the Tokugawa 徳川 era (1600–1868) in Japan, holds a particular fascination that endures to this day. For townfolk and samurai alike, this realm of beauty and entertainment represented an escape from the ordinary, a place where pleasure took priority above all other concerns. However, for the entertainers themselves, this demi-monde was not a temporary refuge from the mundane – quite the opposite. Their occupations conferred them to a strange and, in many ways, unenviable position in society, as caste structure and governmental restrictions isolated performers of the period physically and socially
Pink Silk Dress/Butterfly (image 2)
No full text“When a mountain girl wants a new dress, she catches a butterfly of the desired color, and crushes it between her teeth...”
Given to the University’s Museum by Mrs. B.J. Wade, this pink flowered sprigged dress possibly dates to the early 1900s and could be worn in a variety of settings; including the possibility of “Play Parties.” “Play Parties” are described by Mary Celestia Parler in CBS’ The Search: Folklore in Arkansas as similar to a dance, consisting of folksong instead of instrumentals, hand-swings rather than waist swings and a game that is directed through song.9While this specific garment may not have been worn for events such as this, one thing that remains to be true across cultures and generations is the desire to don a new outfit for a special occasion. Randolph’s conversations with community members proves this to be true as the saying goes, “When a mountain girl wants a new dress, she catches a butterfly of the desired color and crushes it between her teeth...”10
9 Parler, Mary Celestia. “CBS’ The Search: Arkansas.” YouTube, 1950. https://youtu.be/0JX5vQFDln4?si=4lRyBQw26nkPYzED.
10 Randolph, Vance. “Ozark Superstitions.” The American Journal of Folklore 46, no. 179, March 1933.https://scholarworks.uark.edu/uamucc/1005/thumbnail.jp
A Theoretical Investigation of Photo-induced Deformations and Transitions in Nanoscale Ferroelectrics
No full textThis dissertation presents a comprehensive first-principles investigation into the interaction of light with ferroelectric materials, focusing on light-induced structural responses (photostriction) and phase transitions in Ferroelectric superlattices, epitaxially strained BiFeO3 thin films, and twodimensional NbOX2 (X = Cl, Br, I) ferroelectrics. The work aims to provide microscopic insights into how light can control the lattice structure and even the crystallographic phase in these systems, with the broader goal of informing the design of light-responsive functional materials for practical technological applications. The first part explores light-induced effects in PbTiO3/SrTiO3 superlattices with different polarization orientations. Our simulations reveal that photoexcitation modifies the internal electric fields and structural distortions, enabling light-driven control of the superlattice properties and inducing a polarization rotation in the superlattice. These results offer a theoretical foundation that supports and complements existing experimental observations. The second and third parts examine how photostriction in PbTiO3/SrTiO3 depends on structural parameters—specifically, thickness and chemical composition. In ultrathin superlattices, free carriers are delocalized and suppress electric dipoles, resulting in contraction. In thicker superlattices, free carriers are strongly localized at the interfaces, inducing internal fields that suppress existing depolarizing/polarizing fields in PbTiO3 and SrTiO3 layers and produce opposite strain responses in PbTiO3 and SrTiO3 layers, leading to net expansion or contraction. The balance between these competing responses can be engineered by tuning the PbTiO3 fraction, enabling thickness- and composition-dependent control of photostrictive behavior. The fourth part investigates the enhancement of photostriction in BiFeO3 thin films under varying epitaxial strains. We demonstrate that strained BiFeO3 phases near phase boundaries exhibit large light-induced strains, far exceeding those in bulk BiFeO3. This enhancement arises from the coupling between epitaxial strain and the photoexcitation-driven lattice response. The final part focuses on two-dimensional NbOX2 (X = Cl, Br, I) materials. We discover that light can induce phase transitions from ferroelectric or antiferroelectric to paraelectric states, along with significant photostrictive effects. These results highlight the potential of 2D ferroelectrics for next-generation optoelectronic devices. Altogether, this dissertation advances the understanding of light–matter interaction in ferroic systems and establishes practical guidelines for tailoring photostrictive responses through structural and chemical design
Urbanization, Climate Change, and Water Quality in Northwest Arkansas Caves
No full textThe Ozark Cavefish is one of multiple species of conservation concern found in Cave Springs Cave and Logan Cave in Northwest Arkansas (NWA). Over the past two decades, the urbanization of NWA has negatively impacted the recharge areas of both caves, and in turn the water quality of both cave streams. The changing climate has also altered temperature and precipitation, which influence many aspects of karst groundwater. These effects are shown in the historical water quality records for both caves. However, these records are from varied sources and have never been comprehensively compiled and analyzed. This thesis approaches the issue of degraded water quality for these biologically significant caves through compiling a historical database of physical and chemical water measurements for analysis and comparing water quality trends with changes in land use and climate in the recharge areas, as well as comparing trends between each cave. The analysis identified significant differences, trends, and correlations with water temperature, dissolved load, nutrients, and metals. Total dissolved solids, alkalinity, pCO2, calcium, magnesium, and barium concentrations were significantly higher at Cave Springs compared to Logan Cave. Orthophosphate was significantly higher at Logan Cave compared to Cave Springs. At Cave Springs, water temperature, barium, and magnesium increased from 1999 to 2025. At Logan Cave, pH, inorganic nitrogen, and magnesium increased. Before 2015, nitrate concentrations were significantly higher at Cave Springs, but after 2015 the concentrations were higher at Logan Cave. Water temperature was positively correlated with air temperature at Logan Cave, but not at Cave Springs. Calcium was negatively correlated with discharge, and both barium and magnesium were positively correlated with discharge. Both land cover and climate change are likely to contribute to these results, especially with water temperature, nutrients, and metals. The similarities in climate conditions between the two caves indicate many of their differences can be attributed to the different land cover in their recharge areas, as well as to how those land cover differences exacerbate or buffer climate change signals. The analysis was limited by uncertainties in measurement data and constraints of the statistical calculations. Due to the various sources, measurement frequency, conditions, and methods were inconsistent. Both the chemical and statistical calculations required assumptions that simplified the actual conditions. Future research will need to continue monitoring both sites, as well investigate more comprehensively the agricultural operations and urban developments of the recharge areas beyond the scope of the National Land Cover Dataset. The data collected for this thesis will be publicly archived for future use in the conservation and management of these biologically significant caves