Digital Commons Network^™

Why Are Women Tired? Examining Sex-Dependent Effects Of Behavioral Rhythms On Perceived Sleepiness, Maricel Schuler

Theses and Dissertations--Psychology

Sleep complaints in women emerge at menarche and coincide with reproductive hormonal fluctuations throughout the monthly menstrual cycle. To our knowledge, we are the first study (N = 44) to utilize a validated algorithm that uses actigraphy-derived light and activity data in a novel approach to estimate circadian phase, referred here as the photobehavioral phase. We hypothesize that women will have earlier photobehavioral phases, larger phase angles, poorer perceived sleep quality, and greater sleepiness compared to men. In addition, we hypothesize that the perimenstrual phase will be associated with poorer sleep within a subsample of women (N = 15). Contrary …

Interplay Between Computational Techniques And Quantum Theory: Advancing Quantum Chaos And Quantum Error Correction, Refaat Ismail

Theses and Dissertations--Physics and Astronomy

This dissertation investigates computational techniques addressing critical problems arising within quantum chaos and quantum error correction (QEC). First, we investigate quantum dynamics via the Lanczos algorithm, establishing how its computational features — branching patterns, convergence, and complexity saturation — relate to physical properties like spectral statistics and operator matrix elements. We derive a formula connecting Lanczos coefficients to spectral densities for two-branched Lanczos sequences, revealing how branching patterns encode level repulsion—a hallmark of quantum chaos. Furthermore, we develop an analytic framework predicting Krylov complexity saturation from static system properties alone. Specifically, we decompose the saturation value into a spectral density-dependent …

Laser–Assisted Free–Free (Laff) Electron Scattering: An Elastic Angular Distribution In Argon And The Use Of A Novel Pulsed-Laser Multipass System In Laff Experiments, Charles M. Weaver

Theses and Dissertations--Physics and Astronomy

Laser–assisted free–free experiments investigate the emission or absorption of photons when an electron scatters from an atom in the presence of a laser field.

We measured the relative differential cross sections for 350 eV electrons scattered by an argon target in the presence of 1.17 eV photons from a Nd:YAG laser. The angular distribution for elastically scattered 350 eV electrons was measured over scattering angles from 4◦ to 80◦. This distribution exhibits a pronounced maximum near 47◦ and is symmetric about this angle, as predicted by a Kroll–Watson approximation (KWA) calculation for the experimental kinematics. These measurements directly test a …

Quantum Hall Phases In Monolayer Graphene, Jincheng An

Theses and Dissertations--Physics and Astronomy

In the presence of a perpendicular magnetic field, monolayer graphene at and near charge neutrality forms a quantum Hall ferromagnet—a correlated electronic state where the interplay of interactions, spin, and valley degrees of freedom leads to spontaneous symmetry breaking. While the dominant Coulomb interaction has $SU(4)$ symmetry, the ground state is ultimately determined by subdominant terms: residual lattice-scale anisotropic interactions, Zeeman, and sublattice couplings. Relaxing the ultra-short-range limit of anisotropic interactions unveils diverse symmetry-breaking phases in both integer and fractional quantum Hall regimes. Haldane pseudopotentials, which quantify interactions between particle pairs with fixed relative angular momentum, provide a readily parameterizable …

Simulations Of Electron Detection Systematic Errors For A Ucna+ Experiment, Rashika Gupta

Theses and Dissertations--Physics and Astronomy

The Ultracold Neutron Asymmetry+ (UCNA+) experiment at the Los Alamos Neu- tron Science Center (LANSCE) Ultracold Neutron source is an upgrade of the UCNA experiment, designed to measure the neutron beta decay asymmetry parameter, A 0 , with a precision of less than 0.2% using polarized ultracold neutrons (UCN). Neutron beta decay is governed by the weak interaction, and a precise measurement of A 0 provides a determination of the axial-vector to vector coupling ratio, λ = gA /gV . When combined with a measurement of the neutron lifetime, this allows the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element Vud …

Optimizing External Radioactive Calibration Source Strength To Maximize The Livetime Of The Nexo Detector, Thakur P. Bhatta

Theses and Dissertations--Physics and Astronomy

The proposed next Enriched Xenon Observatory (nEXO) experiment aims to detect neutrinoless double beta decay in 136Xe, a rare process with profound implications for particle physics and our understanding of the neutrino. Achieving the required sensitivity demands ultra-low background conditions, making both material radiop urity screening and precise detector calibration essential. This dissertation addresses two key calibration challenges in preparation for nEXO. First, I investigated discrepancies in calibration efficiency measurements of the high-purity germanium (HPGe) detector named as GeIV located 4850 feet under ground at the Sanford Underground Research Facility, Lead, SD. The root cause for the discrepancy was found …

Precision Measurement Of The Muon’ S Anomalous Precession Frequency Using Energy Integrated Analysis In The Fermilab Muon G- 2 Experiment, Joseph Peck

Theses and Dissertations--Physics and Astronomy

This dissertation investigates the anomalous magnetic moment of the muon, aµ, through the Fermilab Muon g -2 Experiment, which aims to measure aµ to a precision of about 140 parts-per-billion.

Muons were injected into a magnetic storage ring where their decay positrons were detected by calorimeters. The changing spin and momentum orientation leads to an oscillation in decay positron counts, known as the anomalous precession frequency ! a. Using the magnetic field and !a measurements, we can determine the value of a µ. This study focuses on the Q-Method determination of !a, which utilizes an energyintegrated reconstruction rather than high-energy …

A Multidisciplinary Approach To The Thermal And Non-Thermal Mechanisms In Galaxy Clusters, Sheng-Chieh Lin

Theses and Dissertations--Physics and Astronomy

Galaxy clusters form at the intersections of the cosmic web and carry imprints of the structure formation history of the universe. As massive, multi-component systems, they offer unique insights into the astrophysical processes that govern both structure formation and galaxy evolution. Observable across the full electromagnetic spectrum, clusters emit photons through a variety of mechanisms, each tracing different physical processes. This dissertation investigates both the thermodynamic and non-thermal properties of the intracluster medium (ICM) to better understand the physical processes shaping observed phenomena. It comprises three main studies, each targeting a different aspect of galaxy cluster physics. In the second …

Structural And Physical Properties Of Solid State Materials: Cegage, Cssni3, And Yb2Si2-XGeXAl, Liam J. Scanlon

Theses and Dissertations--Physics and Astronomy

We present studies of three independent solid state materials: CeGaGe, CsSnI₃, and Yb₂Si_2-xGe_xAl.

CeGaGe is a magnetic candidate Weyl semimetal. Magnetic Weyl semimetals have possible technological applications due to their electronically conducting bulk states, magnetic states, and topologically protected surface states. We grew single crystals of CeGaGe using the zone-refinement method and flux-growth method. With single crystal X-ray and neutron diffraction, we found that zone-refined CeGaGe crystallizes with the I4₁md symmetry (space group 109). With single crystal X-ray diffraction, we found that flux-grown samples of CeGaGe have the …

Students Participating As Ambassadors For Research In Kentucky (Spark): A Health Equity Undergraduate Research Training Program, Ariel A. Arthur, Rebecca L. Delacerda Allen, Fidelis Y. Sesenu, Maxwell A. Groznik, Carrie B. Oser, Madeline Dunfee, Philip A. Kern, Nancy Schoenberg

UK CARES Faculty Publications

The Students Participating as Ambassadors for Research in Kentucky (SPARK) program provides novel health equity research training and targeted mentorship for undergraduates, particularly those from groups underrepresented in the biomedical and behavioral research and workforce. SPARK aims to address inadequate diversity in the medical and scientific research fields by providing comprehensive research mentorship and skill-building. Unlike most existing research training programs that are brief, focus on laboratory research, or are limited to graduate students and junior faculty, SPARK delivers a 16-month intensive behavioral and population health science training, equipping students with needed tools to conceptualize, plan, execute, and analyze their …

Methanogenesis Kinetics Of Organic Matter Of The Leachate In An Up-Flow Anaerobic Sludge Blanket Reactor, Mohamad Ali Fulazzaky, Ali Yuzir, Tiffany L. Messer, Agus Sofyan

UK CARES Faculty Publications

Understanding the treatment of leachate mediated by the development of anaerobic sludge makes it possible to create an effective design process of biodegradation technology. This study used an up-flow anaerobic sludge blanket (UASB) reactor equipped with a gas–liquid-solid separator to capture CH4 for treating landfill leachate to improve understanding of methanogenesis kinetics of organic matter. The performance of UASB was able to remove 154.75 g/L of chemical oxygen demand (COD) content of the leachate originally anticipated to emit 2.99 L of CH4 production into the atmosphere. The trend in the variation of internal mass transfer (IMT) factor was close to …

Physicochemical Property Effects On Immune Modulating Polymeric Nanoparticles: Potential Applications In Spinal Cord Injury, Daniel J. Kolpek, Jaechang Kim, Hisham Mohammed, John C. Gensel, Jonghyuck Park

Markey Cancer Center Faculty Publications

Nanoparticles (NPs) offer promising potential as therapeutic agents for inflammation-related diseases, owing to their capabilities in drug delivery and immune modulation. In preclinical studies focusing on spinal cord injury (SCI), polymeric NPs have demonstrated the ability to reprogram innate immune cells. This reprogramming results in redirecting immune cells away from the injury site, downregulating pro-inflammatory signaling, and promoting a regenerative environment post-injury. However, to fully understand the mechanisms driving these effects and maximize therapeutic efficacy, it is crucial to assess NP interactions with innate immune cells. This review examines how the physicochemical properties of polymeric NPs influence their modulation of …

Towards An Ideal Seed Coating, J M. Scott

IGC Proceedings (1977-2023)

Coated pasture seeds have been formulated in the past based largely on "trial and error" with relatively few objective criteria being employed to define desirable formulations, A description of desirable propelties of various layers of seed coatings and of the seeds themselves is presented.

Lolium Endophyte Viability: Effect Of Seed Storage, M P. Rolston, J R. Crush, M D. Hare, K K. Moore

IGC Proceedings (1977-2023)

The effects of seed storage on the endophyte Acremonium lolii in ryegrass (Lolium perenne L.) were evaluated over 7 years. The long• term effects of 4 seed moisture contents (SMC) 8.6-13.1 %: tempemture (ambient, 5, O, -15°C) 'aitd packaging types: calico, polyethylene fi,Jm. 9-140 µm, and aluminium-polyethylene (AIP) on endophyte viability were assess·ed. • Endophyte viability was maintained by lower seed moisture content and low temperatures. In ambient warehouse conditions endophyte viability declined to zero in 12 months in calico bags,' but was maintained for 3 years at 8.6% SMC in AIP: • Endophyte viability was maintained for …

Effect Of Dormancy-Releasing Treatments On Germination Of Bahiagrass Seed, J. Jeffrey Mullahey, D S. Fisher

IGC Proceedings (1977-2023)

Low seed germination and dormant seed in bahiagrass (Paspalum nonatutum Flugge.) necessitate high seeding rates for successful pasture establishment. A study of dormancy-releasing treatments and age of seed on germination of bahiagrass was conducted in an incubator at the Southwest Florida Research and Education Center near Immokalee, Florida. Five seed treatments (Crop-Start (Solid Matrix Seed Priming, Kamterter Products Inc., Lincoln, NB), potassium nitrate (KNO3), heat/humidity, palea removed, and a check), 2 cullivars (Pensacola, Tifton 9) of bahiagrass and 2 ages (10 and 16 months) of seed were used. A significant (P<0.05) age ·x treatment interaction occurred for all response variables. Based on total germination at 28 days, % dormant seed and rate of germination, Crop-Start and heat/humidity were consistently the best treatments. Additional research on germination with dormancy-releasing treatments is needed to study the Interaction of seed age and bahiagrass cultivar.

Weed Seed Contamination: Use Of A Seed Testing Database To Identify Processing Limitations, J S. Rowarth, M P. Rolston, A A. Johnson

IGC Proceedings (1977-2023)

A computerised database maintained by the Official Seed Testing Station of New Zealand provided the opporlunity to survey weed seed contamination in clover and grass seed-lots. Broad-leaf weeds such as Slierardia arvensis, Stellaria ,nedia and Chenopodium album were the major contaminants in Trifolium repens seed-lots. In grass seed-lots the main contaminants were seeds of other grasses such as Bromus hordaeceus, Vulpia spp. and Holcus lanatus. Weed seeds were found to be a major reason for downgrading or rejection from certification of clover and grass seed-lots in New Zealand; this reflects strict quality control measures.

An Investigation In To The Effect Of Some Factors On The Germination Of Erodium Seeds, Myrna Johnston, Alfredo Olivares, Gladys Fernandez

IGC Proceedings (1977-2023)

Erodiurn seeds present variable dormancy in and even within each species. Thus, it is important to know the factors that determine this variation as related to the persistence of its species. E. rnoschatmn and E. rnalacoides seeds were collected at the end of the annual cycle at La Rinconada de Maipli (33°28'S and 7S050'W). Effects of seed sour.ce (collecting in 1986, 1988 and 1990), age (keeping seeds under laboratory conditions) and maternal factors (cutting plants at early flowering) were analysed. Seeds were tested for germination capacity and germination rate at a constant temperature of 15°C on Petri dishes provided with …

Long-Term Seed Dormancy In Poa Pratensis L. Northern Norway, Trygve S. Aamlid, Dagfinn Arntzen

IGC Proceedings (1977-2023)

Inadequate gennination has often been obseived when planting Poa pratensis L. cv. Lavang (69°N) in northern Norwegian grasslands. This investigation was intended to elucidate whether this was due lo long­term seed dormancy, Seed-lots grown in different years in northern and southern Norway and stored at O-to•c, were germinated in Jakobsen­type germinators al various combinations of temperature and light. Significant dormancy was expressed at 21 °C even after 10 years of storage. Al this constant temperature, germination was promoted by 8 h fluorescent light compared with darkness and continuous light. Al 21/ I 2°C alternating temperature, seed genninated well irrespective of …

Seed Vigour In Lucerne And White Clover, Y R. Wang, J G. Hampton

IGC Proceedings (1977-2023)

Accelerated ageing (AA) was used to assess the seed vigour of 5 lucerne (Medicago sativa L, cv. Wairau) and 8 white clover (Trifolium repens L. cv. Grasslands Huia) seed-lots. Germination prior to AA ranged from 86-94% and 87-94% for the lucerne and white clover seed-lots respectively. All seed-lots hl\d been harvested in 1988 and were certified either as basic or first generation. Germination after 72 h at 40:t0.5°C (AA test) ranged frcim 31-76% for the lucerne seed­lots and 15-56% for che white clover seed-lots, indicating significant differences in seed.vigour among lots of both species. Time of ageing influenced …

Growing Methods For The Morphological Assessment Of White Clover Cultivars Purity, J G. Hampton, E J. Musukwa

IGC Proceedings (1977-2023)

Three growing methods (field sward, field spaced plants, glasshouse plants) were compared for the morphological assessment of white clover (Trifolium repens L.) cultivar purity. Three cerlified (breeders, basic and first generation) seed-lots of cv. Grasslands Kopu and one first generation Kopu seed lot which had been mixed with seed of another cultivnr (10:1) were used to generate data. After analysis of variance (ANOVA), significant (P<0.05) reductions from the breeders seed lot siandnrd for leaf size, stolon number and leaf length/width ratio were recorded for the mixed seed· 101 in nil three growing methods, and for petiole length with the sward method only. With the glasshouse and spaced-plant melhods, slolon numbers of the basic and first generation seed-lots were reduced (P<0.05), while leaf size was lower (P<0.05) for the first generation seed-lot in lhe glasshouse. However, under OECD certification requirements, leaf size of the mixed seed lot was the only characler for which "off types" were detecled. Data coefficients of variation were no greater for the glasshouse method than the required OECD plot-test method.

Importance Of Tropical Pasture Seed Quality And Factors Affecting It In Smallholder Farming System, H F. Chin, C C. Wong

IGC Proceedings (1977-2023)

Most tropical pastures are associated with and confined to smaJlholder animal production in developing countries of the tropics, with the exception of Australia. At present, tropical pasture seeds are very variable and poor in quality, as tropical herbage seed production is relatively new compared with that for temperate systems. Many tropical species are relatively wild and have yet to be domesticated and selected for pasture use, let alone for seed production characteristics. The unfavourable production and storage environment of the wet tropics, coupled with a lack of appropriate technology, also contributes towards poor quality in tropical pasture seeds. In this …

The Benefits Of Seed Quality In Intensive Temperate Forage Systems, Jeffrey J. Steiner

IGC Proceedings (1977-2023)

Seed quality has traditionally been considered to consist of two components: physiologic and genetic quality. The benefits of using high quality seeds have been widely documented and are generally not questioned. These henefits came about as a result of a first­generation of seed quality aware11ess which began more than a century ago. In intensive temperate forage production systems, the producer usually has a ready supply of high-quality seeds available for purchase. For the consumer, seed quality is not a major constraint to system productivity, However, many forage producers are not realising all of the potential benefits from using high quality …

New Realities For The Management Of Tussock Grasslands In New Zealand, I.G C. Kerr

IGC Proceedings (1977-2023)

Concerns about the potential demise of the tussock grasslands of the Soulh Island of New Zealand have been well recorded in the scientific and official literature. Little effective action has been taken to arrest the process of land degradation that has occurred during the 125 years of utilisation of !he tussock grasslands for pastoralism. A substantial decline in the pastoral productivity and conservation value of the "unimproved" tussock grasslands has been the result, Much of the cause has been the failure of the administrators and the occupiers of the high country to understand, and act on, the evidence. Occupiers and …

Integration Of Recreation With Pastoral Use And Conservation In The High Country Of South Island, New Zealand, P H. Murray, D M. Robertson, C R. Mason

IGC Proceedings (1977-2023)

Over 3 000 000 ha of the South Island high country is Crown (i.e. Govemmcnt)-owned land, held under pastoral lease or conservation estate. There is increasing pressure from recreationists for access to land under both tenures. Permits from Crown agents, with agreement from land occupiers, are required for commercial recreation. Access for non-commercial recreation on pastoral lease land is generally through direct negotiation with the lessee. Conflicts between high country users are occurring where recreation pressure is greatest. A case study in the Remarkables Range near the mountain resort of Queenstown, shows domination by the primary users (pastoral lessees and …

Tradition And Pastoral Sustainability- An Exercise In The Applied Human Ecology Of Mountain Rangelands, David Pitt

IGC Proceedings (1977-2023)

The paper presents the case for regarding some traditional practices and customs as a ba��e for sustainable development in winter cold temperate rangeland pastoralism, The emphasis is on the social forms which maintain a system in which low intensity production, usufruct, kinship dynamics, co-operation, environmentally friendly practices and nomadism are maintained in the face of extreme outside pressures, A typology is elaborated including five situations: independence, coexistence, fluctuation, absorption and interaction. Case studies _are presented from the Middle East, Andes, North Africa, the Alps, the Himalaya and the former Soviet Union. Although these situations are basically historical, or at best …

Integration Of Pastoral And Non-Pastoral Uses On Temperate Rangelands With Cold Winters In Developed Countries, T J. Maxwell, W A. Laycock

IGC Proceedings (1977-2023)

The demands of the relatively wealthy and sophisticated societies of developed countries, with their substantial amounts of leisure time and discretionary income, are having an increasing impact on temperate rangelands in a variety of ways. Some parts of these societies are concerned to protect the landscapes, habitats, wildlife and solitude that can be found there, and wish to constrain any further development within these ecosystems; others also wish .to gain ready access to these resources for hunting, recreation and sport and believe that this requires the exclusion of domesticated livestock. Temperate rangelands are frequently used as water catchments and some …

Effects Of Date Of Harvest On Yield And Quality Of Meadow Fescue Seed, Uwe Simon

IGC Proceedings (1977-2023)

A seed-shattering-resistant cultivar and a normal cultivar of meadow rescue (Festuca pratensis Huds.) were harvested for seed 10 times in regular intervals during a period of 30 days, The effects of harvesting time on yield, water content, germination and weight of seeds, and on costs of seed processing were studied in the 2 types of cultivar. Yield losses due to premature harvest were greater than losses due to delayed harvest. Seed losses due to shattering were smaller in the shattering-resistant cultivar compared with the normal cultivar. The water content of the seeds decreased with advancing maturity, from =50% to .. …

After-Effects Of Grass Seed Production On Subsequent Field Crops, Uwe Simon

IGC Proceedings (1977-2023)

Forage grasses grown for the production of seed are usually components of a crop rotation. The after-effects of 3 grass species compared with 4 crop species on the yields of 5 field crops in the first and second year after grass seed harvest were investigated. Significant differences between the grass species, and between grasses and other field crops on subsequent crops, and between the subsequent crops in their reactions to the preceding crops were obvious in both years after grass seed harvest, Annual and perennial ryegrass excited the most positive effects on subsequent crop yields. Corn and sugarbeets responded particularly …

A New Power Airflow Harvester Improves Grass Seed Yield And Quality In Central Queensland, Australia, J H. Wildin, Dingfa Zhou, A Dobson

IGC Proceedings (1977-2023)

Most perennial tropical grasses produce new seedheads over a period extending up to 4 weeks, Seeds mature and ripen up to 4 weeks after inflorescence emergence. The dilemma for seed producers using one­pass harvesting has been to time the harvesting operation to maxmise. recovery of mature seed, Harvested immature seeds and inert material adversely affect seed purity and germination tests. Light fluffy seeds such as buffel and bluegrasses are generally difficult to harvest with grain crop harvesters, and paddle beater harvesters have been used for simplicity and economy. Over the last 3 years, tractor-mounted brush harvesters using 4 rows of …

Evaluation And Development Of Brush Harvesting For Chaffy-Seed Grasses In Queensland, Australia, T A. Jensen, D S. Loch, B G. Robotham

IGC Proceedings (1977-2023)

Lack of an effective seed harvester has limited the commercial availability of many chaffy-seeded grasses in Australia. A brush harvester similar to the Woodward Plail-Vac. Seed Stripper was evaluated successfully across a range of chaffy-seeded grasses in southern Queensland. A second machine with increased harvesting and storage capacity plus a facility for primary cleaning of seed was designed and built for large-scale commercial use. A third harvester is currently being developed for opportunist harvesting of small discontinuous seed areas, particularly of chaffy-seeded native grasses in the, semi-arid mulga lands in south-western Queensland; it is designed for low-cost construction and maintenance …