Physical Sciences and Mathematics Commons^™

Mgrre_Thinsections_Mgrre-124_5, Mgrre

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No abstract provided.

Utilization And Efficient Computation Of Polarization Factor Q For Fast, Accurate Brdf Modeling, Samuel D. Butler, Michael A. Marciniak

Faculty Publications

The Bidirectional Reflectance Distribution Function (BRDF) is of substantial use in remote sensing, scene generation, and computer graphics, to describe optical scatter off realistic surfaces. This paper begins by summarizing our prior work in relating wave optics and geometric optics models, culminating with the Modified Cook-Torrance (MCT) model. The MCT model is evaluated here against aluminum, Infragold, and silver paint at various wavelengths in the IR. In each case, the MCT model is shown to outperform a standard microfacet model. Then, this paper shows a non-trivial method of computing the primary new term, the polarization factor Q. This optimization …

Maximum Entropy And Constraints In Composite Systems, John D. Ramshaw

Physics Faculty Publications and Presentations

The principle of maximum entropy (PME), as expounded by Jaynes, is based on the maximization of the Boltzmann-Gibbs-Shannon (BGS) entropy subject to linear constraints. The resulting probability distributions are of canonical (exponential) form. However, the rationale for linear constraints is nebulous, and probability distributions are not always canonical. Here we show that the correct noncanonical distribution for a system in equilibrium with a finite heat bath is implied by the unconstrained maximization of the total BGS entropy of the system and bath together. This procedure is shown to be equivalent to maximizing the BGS entropy of the system alone subject …

Variability Of Potential Soil Nitrogen Cycling Rates In Stormwater Bioretention Facilities, Erin N. Rivers, Jennifer L. Morse

Environmental Science and Management Faculty Publications and Presentations

Low-impact development (LID) is a common management practice used to infiltrate and filter stormwater through vegetated soil systems. The pollutant reduction potential of these systems is often characterized by a single pollutant removal rate; however, the biophysical properties of soils that regulate the removal of pollutants can be highly variable depending on environmental conditions. The goal of this study was to characterize the variability of soil properties and nitrogen (N) cycling rates in bioretention facilities (BRFs). Soil properties and potential N cycling processes were measured in nine curbside bioretention facilities (BRFs) in Portland, OR during summer and winter seasons, and …

Effect Of Interfacial Atomic Mixing On The Thermal Conductivity Of Multi-Layered Stacking Structure, Yingguang Liu, Xinqiang Xue, Guoliang Ren, Aleksandr V. Chernatynskiy

Physics Faculty Research & Creative Works

Multi-layered stacking structures and atomic mixing interfaces were constructed. The effects of various factors on the thermal conductivity of different lattice structures were studied by non-equilibrium molecular dynamics simulations, including the number of atomic mixing layers, temperature, total length of the system, and period length. The results showed that the mixing of two and four layers of atoms can improve the thermal conductivities of the multi-layer structure with a small total length due to a phonon "bridge" mechanism. When the total length of the system is large, the thermal conductivity of the multi-layer structure with atomic mixing interfaces decreases significantly …

Phenanthrene: Establishing Lower And Upper Bounds To The Binding Energy Of A Very Weakly Bound Anion, Elisabeth Gruber, Siegfried Kollotzek, Stefan Bergmeister, Fabio Zappa, Milan Ončák, Paul Scheier, Olof E. Echt

Faculty Publications

Quite a few molecules do not form stable anions that survive the time needed for their detection; their electron affinities (EA) are either very small or negative. How does one measure the EA if the anion cannot be observed? Or, at least, can one establish lower and upper bounds to their EA? We propose two approaches that provide lower and upper bounds. We choose the phenanthrene (Ph) molecule whose EA is controversial. Through competition between helium evaporation and electron detachment in He_nPh^- clusters, formed in helium nanodroplets, we estimate the lower bound of the vertical detachment energy …

Speciation Of Diaryliodonium Salts In Solution And Their Reactivity Towards N-Nucleophiles (Phthalimide And Amines) And O-Nucleophiles (Phenols And Phenoxide), Souradeep Basu

Dissertations and Theses

Benzenoid rings are prevalent in pharmaceutical drug molecules, agrochemical molecules and even in some polymers used in electronic device. Aryl rings are often installed using metal catalysis, however, metal free arylations are known but limited. Diaryliodonium salts are novel electrophilic arylating agents. Herein, metal free N-arylation of phthalimide and diarylether formation using aryl(TMP)iodonium salts is described.

The structure of diaryliodonium salts has been primarily studied in either the solid state or in-silico. The structure and speciation of diaryliodonium salts in solution is not well explored. In this work evidence of dimer formation of aryl(Mes)iodonium salts in chloroform using …

Machine Learning To Predict Sports-Related Concussion Recovery Using Clinical Data, Yan Chu, Gregory Knell, Riley P. Brayton, Scott O. Burkhart, Xiaoqian Jiang, Shayan Shams

Faculty Research, Scholarly, and Creative Activity

Objectives
Sport-related concussions (SRCs) are a concern for high school athletes. Understanding factors contributing to SRC recovery time may improve clinical management. However, the complexity of the many clinical measures of concussion data precludes many traditional methods. This study aimed to answer the question, what is the utility of modeling clinical concussion data using machine-learning algorithms for predicting SRC recovery time and protracted recovery?
Methods
This was a retrospective case series of participants aged 8 to 18 years with a diagnosis of SRC. A 6-part measure was administered to assess pre-injury risk factors, initial injury severity, and post-concussion symptoms, including …

Release Of A New Forage Bermudagrass Cultivar From The Usda-Npgs Cynodon Collection, Esteban F. Rios, José C. B. Dubeux Jr., João M. B. Vendramini, M. Wallau, C. H. Lopes De Souza, A. J. Grossman, Y. Lopez, P. Munoz, W. Anderson, L. Baxter, M. S. Castillo, M. C. Saha, K. Quesenberry, A. Blount, P. Reith, K. Kenworthy

IGC Proceedings (1993-2023)

Warm-season perennial grasses are the backbone of the pasture-based livestock industry in the southeastern USA. In Florida specifically, bahiagrass (Paspalum notatum Flugge) and bermudagrass (Cynodon spp.) support 1 million head of cattle and 15,000 beef cattle operations. Bermudagrass is the most widely planted forage species in the southeastern USA, planted in approximately 15 million ha and used for grazing, hay and silage. The genus Cynodon is native to southern Africa and germplasm collections have revealed a high degree of genetic variability within the genus. The United States Department of Agriculture National Plant Germplasm System (USDA-NPGS) maintains a collection …

Relationship Between Semi-Arid Rangelands Quality Parameters And Vegetation Indexes, P. Toro-Mujica, D. Enriquez-Hidalgo, S. Escobar

IGC Proceedings (1993-2023)

A large portion of the sheep production systems in the semi-arid zone of Central Chile base their feeding on the rangelands, adjusting both the production cycle and the use of supplementary feed to the natural supply of fodder. In this way, knowledge of the rangeland quantity and quality at the farm level emerges as an essential input for the decision-making of feed management. The objective of the study was to relate the herbage quality parameters of the semi-arid zone rangeland with Vegetation Indices (VI) and to determine which vegetation index report the best results. Vegetative indexes were obtained from aerial …

Predicting Forage Intake By Sheep Through The Pampa Corte Model Or Nrc, C. A. Pozo, Gilberto V. Kozloski, H. M. N. Ribeiro Filho, J. F. Tourrand, Vicente Celestino Pires Silveira

IGC Proceedings (1993-2023)

The aim of the present study was to evaluate the precision and accuracy of the Pampa Corte and National Research Council (2007; NRC) models for predicting forage intake (FI) by sheep. Individual data (n = 213) of observed FI, body weight and chemical composition of consumed diet were taken from fifteen indoor digestibility trials conducted with male sheep housed in metabolic cages and fed only forage ad libitum. The diets were composed of tropical grasses, temperate grasses and legumes. Individual observations of FI were averaged by treatment (n = 32) into each experiment which were then compared to FI …

Performance Of Napier Grass (Cenchrus Purpureus L.) Genotypes Grown Under Limited Soil Moisture, E. Habte, M. S. Muktar, A. T. Negawo, A. M. Sartie, C. S. Jones

IGC Proceedings (1993-2023)

Napier grass (Cenchrus purpureus Schumach L.) is an important perennial forage native to Africa and grown in many tropical and subtropical countries. It is considered as a short-term drought tolerant forage which is a useful trait in areas that are characterized by low precipitation during the dry season. To exploit the potential of this grass and identify water use efficient (WUE) genotypes, a field drought stress trial was conducted at Bishoftu, Ethiopia. Eighty-four Napier grass genotypes were planted in a p-rep design in four replications. The genotypes were evaluated for forage performance during the dry season of 2019 and …

Performance Of The Leucaena Leucocephala–Megathyrsus Maximus Cv Mombasa System And Local Range Grazed By Pelibuey Ewe-Lambs, E. Cortés Díaz, J. C. Campos Ojeda, P. Martínez Hernández, J. L. Zaragoza Ramírez

IGC Proceedings (1993-2023)

Mombasa grass and leucaena have shown an excellent agronomic performance grown in tropical semi-arid ranges, the objective of this study was to compare the agronomic performance of Leucaena-Mombasa grown as a silvopastoral system at two leucaena plant densities (10000 and 15000 plants ha^-1) and of Pelibuey ewe-lambs grazing it against native unimproved tropical semi-arid range of the state of Morelos, México. Experimental design was a completely random with two replications. Unimproved native range was mainly deciduous shrubs and mixed herbaceous plants (Poaceae and Asteraceae). Stocking rate was the same across treatments and grazing lasted all rainy season. Of …

Pasture Utilization At Islands In Northern Norway, V. Lind, Ø. Holand, F.-A. Haugen, G. Steinheim

IGC Proceedings (1993-2023)

The Norwegian sheep industry is based on utilization of “free” rangeland pasture resources. Use of mountain pastures is dominating, with about two million sheep grazing these pastures during summer. Regional challenges related to e.g., loss of sheep to large carnivores make farmers think differently. The Norwegian coastline is among the longest globally and is scattered with islets and islands. Alone along the coast of Nordland county, it is estimated more than 14,000 islands. Use of islands for summer pasture is an alternative but there is a limited knowledge about such a management system. In this study, we examined lambs’ average …

Noninvasive Detection, Tracking, And Characterization Of Aerogel Implants Using Diagnostic Ultrasound, Sagar Ghimire, Martina Rodriguez Sala, Swetha Chandrasekaran, Grigorios Raptopoulos, Marcus Worsley, Patrina Paraskevopoulou, Nicholas Leventis, Firouzeh Sabri

Chemistry Faculty Research & Creative Works

Medical implants are routinely tracked and monitored using different techniques, such as MRI, X‐ray, and ultrasound. Due to the need for ionizing radiation, the two former methods pose a significant risk to tissue. Ultrasound imaging, however, is non‐invasive and presents no known risk to human tissue. Aerogels are an emerging material with great potential in biomedical implants. While qualitative observation of ultrasound images by experts can already provide a lot of infor-mation about the implants and the surrounding structures, this paper describes the development and study of two simple B‐Mode image analysis techniques based on attenuation measurements and echogenicity comparisons, …

Uncharted Territories: Covid-19 And Other 2020 Events That Changed Lives Forever, Justina Ogodo

Journal of Multicultural Affairs

The year 2020 rolled in with pomp and pageantry like any other year in human history. I assume that many like me had high hopes, possibly made new year resolutions. I looked forward to the new year with great expectations—planned trips, events, graduations, weddings, and even new writing goals and aspirations. But the year had its own plan, taking an unexpected turn. I am a science educator, wife, and mother of three black children; I walked into the uncharted territories of COVID-19 and other 2020 events that changed lives forever. I tell this story of my lived experience with a …

Participatory Evaluation Of Urochloa And Megathyrsus Forage Species In Western Kenya: Farmers Perspective, Ruth Odhiambo, Solomon Mwendia, David Mwangi, Alfred Juma, An Notenbaert

IGC Proceedings (1993-2023)

Despite western Kenya potential in dairy production, it has lagged behind compared to other regions in the country. This comes against growing per capita milk consumption in Kenya currently estimated at 120 litres per person per year. As a result, western Kenya is largely net importer of milk from neighbouring counties albeit the possibility improving productivity within. Among the most prevalent constraint to increased productivity is limited forage quality and quantity throughout the year. Napier stunting disease, which suppresses forage production from Napier grass, the most prevalent cultivated forage in western Kenya, exacerbates this. To contribute to addressing the problem, …

Nutritional Quality Of Available Forages For Small Stock During A Drought In An Arid Pastoral Landscape In South Africa, M. I. Samuels, F. L. Müller, C. F. Cupido, M. B. V. Swarts, L. F. Cyster

IGC Proceedings (1993-2023)

This study aimed to assess the nutritional quality of the available forage species during a drought in an arid pastoral system in South Africa. Forage biomass was collected during the wet and dry seasons whilst following livestock herds consisting of boer goats, swakara sheep and mixed breed sheep, in both the summer and winter rainfall regions of the pastoral system. Mineral nutrient content in the plant species revealed that the forages utilized by the livestock generally contained adequate concentrations of Mg, Ca, Na, and K to meet the dietary requirements of the small stock in both the winter and summer …

Mineral Profile Of Panicum Maximum Var. Ntchisi As Influenced By Organic Nitrogen Rate And Age At Harvest, P. Dele, B. Akinyemi, O. Oyeleke, C. Anotaenwere, F. Salawu, S. O. Onifade

IGC Proceedings (1993-2023)

The study was aimed at profiling the mineral contents of Panicum maximum var Ntchisi as influenced by organic (poultry) nitrogen rate and age at harvest. The study was carried out at the organic research farm of the Federal University of Agriculture, Abeokuta, Nigeria in 2016. The experiment was laid in a 4 x 3 factorial arrangement in a split plot design with four (4) organic nitrogen rate (0, 100, 200 and 300 kgNha^-1) as the main plot and three (3) age at harvest (4, 8 and 12 weeks after cutback) as the subplot which amounts to twelve (12) …

Nutritional Characterisation Of Introduced Improved Brachiaria Grasses In Rwanda, M. Mutimura, P. C. Hitimana

IGC Proceedings (1993-2023)

A study aimed at characterising nutritive value of introduced Brachiaria grasses in Rwanda was conducted. Four Brachiaria grasses including, Brachiaria decumbens cv. Basilisk, Brachiaria brizantha cv. MG4, Brachiaria brizantha cv. Piata and Brachiaria cv. Cayman with Panicum coloratum as control were planted in two contrasting environments of low rainfall in Kirehe district and acidic soils in Nyamagabe district. The experiment was set in a randomized complete block design (RCBD) with four replications and the treatments were harvested after 60 days and 90 days. Data collected were dry matter (DM), crude proteins (CP), organic matter (OM), cellulose, neutral detergent fibre (NDF), …

Microbial Population And Fermentation Characteristics Of Total Mixed Ration Prepared With Local Feed Resources In Mozambique, Y. Cai, Z. Du, S. Yamasaki, D. Nguluve, F. Macome, T. Oya

IGC Proceedings (1993-2023)

To effectively utilize locally available feed resources for dairy cattle in Africa, fermented total mixed ration (TMR) was prepared using Napier grass, corn meal, wheat bran, formula feed, and mineral and vitamin mix. The fermentation quality of TMR were analyzed after 14 days of ensiling. Before ensiling, aerobic bacteria were the dominant bacteria, after ensiling, lactic acid bacteria counts increased rapidly and became the dominant bacteria in TMR. After 14 days of ensiling, aerobic bacteria, coliform bacteria, yeasts, and molds showed lower (P < 0.05) counts in TMR than those before ensiling. The dry matter (DM) of TMR was adjusted to 45.50%, their crude protein and neutral detergent fiber contents were approximately 11.48, and 55.25% of DM, respectively. After 14 days of ensiling, TMR fermented to a good quality, the pH was reduced to 3.90; the lactic acid and ammonia nitrogen contents were 1.01 and 0.31% of FM, respectively; the propionic acid and butyric acid were too low to detect. The results confirm that fermented TMR prepared with local feed resources can attain a good quality in Africa.

The Dynamical Evolution Of Classical Be Stars, Keegan Marr

Electronic Thesis and Dissertation Repository

This thesis focuses on the evolution of the disks of two classical B-emission (Be) stars, 66 Ophiuchi and Pleione, and on the thermal structure for disks tilted out of the star's equatorial plane.

We used a hydrodynamic code to model the disk of the Be star 66 Ophiuchi. Observations from 1957 to 2020 were compiled to follow the growth and subsequent dissipation of the disk. Our models are constrained by new and archival photometry, spectroscopy and polarization observations. Using Markov chain Monte Carlo methods, we confirm that 66 Oph is a B2Ve star. We constrain the density profile of the …

Learning Temporal Rules From Noisy Timeseries Data, Karan Samel, Zelin Zao, Binghong Chen, Shuang Li, Dharmashankar Subramanian, Irfan A. Essa, Le Song

Machine Learning Faculty Publications

Events across a timeline are a common data representation, seen in different temporal modalities. Individual atomic events can occur in a certain temporal ordering to compose higher level composite events. Examples of a composite event are a patient's medical symptom or a baseball player hitting a home run, caused distinct temporal orderings of patient vitals and player movements respectively. Such salient composite events are provided as labels in temporal datasets and most works optimize models to predict these composite event labels directly. We focus on uncovering the underlying atomic events and their relations that lead to the composite events within …

The Fierce Green Fire: Vol. 12 Issue 10, Wofford College. Department Of Environmental Studies

The Fierce Green Fire

No abstract provided.

Fluids And Melts At The Magmatic-Hydrothermal Transition, Recorded By Unidirectional Solidification Textures At Saginaw Hill, Arizona, Usa, Wyatt M. Bain, Pilar Lecumberri-Sanchez, Erin E. Marsh, Matthew Steele-Macinnis

United States Geological Survey: Staff Publications

Fluid exsolution and melt evolution at the magmatic-hydrothermal transition are critical processes driving the metal enrichment of porphyry systems. Coeval fluid and melt inclusion assemblages in unidirectional solidification textures (USTs) at Saginaw Hill—a small, porphyry Cu system in southwestern Arizona—record a dynamic and repetitious process of fluid accumulation and release. The cores of quartz crystals throughout the UST bands host coeval silicate melt and brine inclusions but lack vapor-rich inclusions. This could indicate preferential expulsion of vapor and trapping of high-density brine during episodes of fracturing or the direct exsolution of single-phase high-salinity brine from the silicate melt. In contrast, …

Multidimensional, High Precision Measurements Of Beam Single Spin Asymmetries In Semi-Inclusive Pi+ Electroproduction Off Protons In The Valence Region, S. Diehl, A. Kim, G. Angelini, K. Joo, S. Adhikari, M. Amaryan, M. Arratia, H. Atac, H. Avakian, C. Ayerbe Gayoso, N. A. Baltzell, L. Barion, S. Bastami, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, F. Bossù, Steffen Strauch, Et. Al.

Faculty Publications

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single πþ SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q² ranging from 1–7 GeV². In particular, the structure function ratio ^sinϕ _LU/ F_UU has been determined, where ^sinϕ _LU is a twist-3 quantity that …

Potential Of C4 Tropical Grasses To Contribute In Carbon Sequestration, Environmental Security And Livelihood Opportunities Through Increased Fodder Availability, D. R. Malaviya, A. K. Roy, P. Kaushal

IGC Proceedings (1993-2023)

The world grasslands/rangeland ecosystems comprise 26% of earth’s surface and have immense ecological and economic significance. Diversity of grasslands had been a key element for their sustainability. Grasslands in India have existed as natural ecosystems for millions of years. It is a major source of income, employment and livelihood to the rural families. Owing to heavy grazing pressure, coupled with other social/anthropogenic factors, the grazing resources have fast deteriorated. The country has many old and natural grasslands with ethnic and economic value. Comprehensive ecological studies including floristic compositions, dominant species, grazing pressure and the climax/sub-climax stages of ecological succession will …

Linking Ground, Space And Knowledge: The Role Of Weather Forecasting In Pastoralists' Decision-Making, E. L. Mulder, V. C. Wright, S. C. Steele-Dunne, P. H. A. J. M. Van Gelder, H. C. Winsemius

IGC Proceedings (1993-2023)

Changing weather patterns and decreasing land availability continue to challenge the livelihood of the pastoralists in northern Tanzania. The increasing variability of expected rains has complicated livestock management, often jeopardizing household resilience. Drought Early Warning Systems are being set up to contribute to decision-making processes at national and international levels. Nevertheless, due to the large spatial- and temporal resolution of these systems and their high uncertainties, these systems have limited value at a pastoral household level.

Therefore, this paper explores what type of weather and climate information is deemed valuable for pastoral households in Longido District, Tanzania. It is based …

Microbiome Of The Cool Season Forage Grass Timothy (Phleum Pratense L.) And Its Potential Role In Stress Tolerance, Dina Saleh, Suha Jabaji, Philippe Seguin

IGC Proceedings (1993-2023)

The functional attributes of the microbiome associated with timothy for growth promotion properties, antimicrobial and biosurfactant capacities were characterized. A total of 254 culturable bacteria were identified by 16S rRNA sequencing and grouped into 16 taxa that shared high homology of 98–99% with other known sequences. The majority of bacterial isolates exhibited multifunctional growth promotion attributes and plant stress improvement. The selection of competent and compatible strains for application in forage production is dependent on the recognition of root exudates and motility towards the roots, attachment to the root surface, formation of biofilm, penetration, and colonization of internal tissues. We …

Improving The Functionality Of Water Investments In The Drylands: Learning From Kenya’S County Climate Change Fund, C. Bedelian, M. Bonaya, A. Ibrahim, F. Ngarachu, C. Hesse

IGC Proceedings (1993-2023)

Kenya’s County Climate Change Fund (CCCF) is financing public good investments focused on the water sector to increase the resilience of communities to climate change. In the drylands, investments in water are critical for water and food security, yet ensuring the functionality and sustainability of water investments remains an ongoing challenge. This paper assesses the functionality and sustainability of 62 CCCF water investments in five dryland counties (Isiolo, Wajir, Garissa, Kitui and Makueni) in Kenya through a functionality survey and stakeholder workshops. The survey was designed based on a review of studies assessing the functionality of water supply systems. Across …