Physical Sciences and Mathematics Commons^™

Public Mass Shootings In Texas And California: Routine Activity Theory Comparisons, Mason R. Feinartz

Doctoral Dissertations and Projects

Public mass shootings are a distinct and unique phenomenon that receives vast media and public attention due to the location, weapons used, and amount of people killed or injured. These mass shootings occur in places where people frequent daily in their routine activities and are unexpected, seemingly random, or symbolic events. This study used a casual-comparative quantitative research design using routine activity theory as the foundation to investigate public mass shootings in Texas and California from 1966 to 2023. This study used public open-source data collection and analysis to identify and substantiate all mass shootings that satisfy the research inclusion/exclusion …

Questioning Reality: The Progressive Development Of Modern Physics, Joshua Lancman

STEM Month

Humanity has a tendency to divide time. The past is distinct from the present which is entirely separate from the future. In supposedly 20-20 vision history is neatly divided into different sections, distinct eras with sharp lines between them. What is present and in the future is always modern. What is past is something else with another name.

Yet time is not divided so neatly. We know this living through it: years and decades blend into one another in a non-uniform progression. To divide human history into separate eras is a necessary simplification, as it helps to ascribe order onto …

Mercury Exposure, Fuel Stores And Torpor Use In Silver Haired Bats, Melina Kuerschner

Electronic Thesis and Dissertation Repository

Methylmercury (MeHg) is an environmental contaminant that has a high biomagnification potential with potent neurotoxic effects. Insectivorous bats may be readily exposed to MeHg through their diet. To test the effect of exposure on torpor and body composition in silver-haired bats (Lasionycteris noctivagans), I measured total mercury (THg, combination of inorganic and methylmercury) through fur samples and quantitative magnetic resonance analysis, temperature sensitive radio tags, and respirometry data from these bats to quantify body composition and torpor use. THg levels varied 20-fold with heavier and fatter bats having higher levels, suggesting that individuals that routinely eat more accumulate …

Predictive Models Of Polymer Composites: A Thesis, Navid Afrasiabian

Electronic Thesis and Dissertation Repository

Predictive models are a powerful tool to understand and improve physical systems. Predictive models not only can be used to improve current materials, but they also gain fundamental understanding of the underlying processes. There are numerous theoretical and numerical models introduced in the field of polymer composites and nanocomposites. Different methods best describe a system at a specific time and length scale. In this thesis, I utilize Coarse-grained Molecular Dynamics (CGMD), Multi-PhaseField (MPF), and Lattice-Boltzmann (LB) methods to study different aspect of polymer composites and nanocomposites.

Starting at the nanoscale, we study the dispersion and orientation patterns of nanorod-polymer systems …

Coffee In Brasil: Sustainability And The Role Of Intermediaries, Livia Petzinger

Capstone Collection

ABSTRACT

Coffee is traded in a highly complex global value chain where countless sustainability initiatives have emerged to address social, economic, and environmental issues, challenges which persist due to dominance of the market structure by largescale traders and roasters. Specialty coffee and direct trade have emerged as alternative trade arrangements that promote high-quality coffee through the use of sustainable practices, transparency, and a shortened supply chain. This research analyzes the role that intermediaries in the Brazilian specialty coffee supply chain play in the implementation of sustainability initiatives asking what kinds of sustainability practices they implement and why, and how this …

Solar Photovoltaics As Climate Change Adaptations For Farmers In West Bengal, India: Barriers Within A Food-Water-Energy Nexus Approach, Emily Rochford

Capstone Collection

This capstone research project seeks to identify and address barriers to the use of solar photovoltaics (PV) as an adaptation method to climate change for farmers in West Bengal, India. These barriers are examined within the context of the food-water-energy nexus, particularly concerning the ability of many small holder farmers to produce their own food and sustain their livelihoods. Previous studies have examined both energy access and renewable energy development in West Bengal, and also the food-water-energy nexus in its application to climate change. However, there is minimal literature on how renewable energy development should be applied within the nexus …

A Measure Of Interactive Complexity In Network Models, Will Deter

Northeast Journal of Complex Systems (NEJCS)

This work presents an innovative approach to understanding and measuring complexity in network models. We revisit several classic characterizations of complexity and propose a novel measure that represents complexity as an interactive process. This measure incorporates transfer entropy and Jensen-Shannon divergence to quantify both the information transfer within a system and the dynamism of its constituents’ state changes. To validate our measure, we apply it to several well-known simulation models implemented in Python, including: two models of residential segregation, Conway’s Game of Life, and the Susceptible-Infected-Susceptible (SIS) model. Our results reveal varied trajectories of complexity, demonstrating the efficacy and sensitivity …

Returning Power To The Mashpee Wampanoag Tribe: Energy Policy And Tribal Autonomy, Nicolas Land-Kazlauskas

Capstone Collection

This policy brief addresses tribal autonomy, energy policy, and the resources of the Mashpee Wampanoag Tribe in Massachusetts. Tribal sovereignty has been a difficult and often painful area of discussion for many tribal communities. For generations, tribes have had to carefully navigate their interactions with colonial forces and the residues of colonialist legacies, especially tied to resource wealth and decision-making. Even with the best of efforts by the tribe, their actions often have not impacted the basic legal or economic situations on-the-ground. Their on-going relationships with states and companies continue to undermine tribal autonomy and sovereignty oftentimes simply because they …

Revolutionizing Wild Silk Fibers: Ultrasound Enhances Structure, Properties, And Regenerability Of Protein Biomaterials In Ionic Liquids., Xincheng Zhuang, Haomiao Zhu, Fang Wang, Xiao Hu

College of Science & Mathematics Departmental Research

Ultrasound-assisted regulation of biomaterial properties has attracted increasing attention due to the unique reaction conditions induced by ultrasound cavitation. In this study, we explored the fabrication of wild tussah silk nanofiber membranes via ultrasound spray spinning from an ionic liquid system, characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), atomic force microscopy (AFM), water contact angle, cytocompatibility tests, and enzymatic degradation studies. We investigated the effects of ultrasound propagation in an ionic liquid on the morphology, structure, thermal and mechanical properties, surface hydrophilicity, biocompatibility, and biodegradability …

Green Synthesis Of Carbonized Chitosan-Fe3o4-Sio2 Nano-Composite For Adsorption Of Heavy Metals From Aqueous Solutions, Dalia A. Ali Eng, Rinad Galal Ali Eng.

Chemical Engineering

Water pollution with heavy metals owing to industrial and agricultural activities have become a critical dilemma to humans, plants as well as the marine environment. Therefore, it is of great importance that the carcinogenic heavy metals present in wastewater to be eliminated through designing treatment technologies that can remove multiple pollutants. A novel green magnetic nano-composite called (Carbonized Chitosan-Fe3O4-SiO2) was synthesized using Co-precipitation method to adsorb a mixture of heavy metal ions included; cobalt (Co2+), nickel (Ni2+) and copper (Cu2+) ions from aqueous solutions. The novelty of this study was the synthesis of a new

nano-composite which was green with …

63rd Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 63rd annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in the Copper Conference Center, Copper Mountain, Colorado, August 4-8, 2024.

2024 August 8 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Impact Of Land Use Dynamics On The Water Yields In The Gorgan River Basin, Masoomeh Yaghoobi, Aram Fathi, Shahryar Fazli, Wenzhao Li, Elham Haghshenas, Vahid Shokri Kuchak, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

This research investigates the future dynamics of water yield services in the Gorgan River Basin in the North of Iran by analyzing land cover changes from 1990 to 2020, using Landsat images and predicting up to 2040 with the Land Change Modeler and InVEST model under three scenarios: continuation, conservation, and mitigation. The results indicate significant shifts in agricultural land impacted water yields, which fluctuated from 324.7 million cubic meters (MCM) in 1990 to 279.7 MCM in 2010, before rising to 320.1 MCM by 2020. The study uniquely assesses the effects of land use changes on water yields, projecting a …

Multi-Species Toxicity Testing Of Iprnhc: A Candidate For Organic Coating Enhancements, Maryam Khalilvand Nahid

Electronic Thesis and Dissertation Repository

Corrosion is a natural process affecting the longevity and integrity of metals. N-Heterocyclic carbenes (NHCs) are robust organic compounds that can form strong σ-bonds with metal atoms, allowing for the formation of monolayers on the metal surface. This property makes NHCs promising for coating metals. However, their long-term effects on the aquatic environment are not well understood. The present study investigated the ecotoxicity of 1,3-diisopropyl-1H-benzoimidazolium bicarbonate (iPrNHC NCO₃^-), a candidate for organic coating enhancements, on various species of aquatic organisms. The results showed that high concentrations of iPrNHC significantly increased mortality rates in zebrafish embryos, planarians, Daphnia, …

Effects Of Cutting Management On Herbage Production And Tiller Population In Smooth Bromegrass (Bromus Inermis Leyss), J X. Xia, J Hodgson, A.C P. Chu, P Wang, F Y. Liu

IGC Proceedings (1993-2023)

This paper reports the results of an experiment with smooth bromegrass (Bromus inermis Leyss) under cutting management at Beijing Agricultural University, China from June-October 1989. The main treatments were cutting intervals (l month v. 2 months) and cutting height (10 cm v. 30 cm) with 2 additional treatments (uncut control, and delayed first cut) and 4 replications. Frequent cutting decreased tiller population density, herbage accumulation and underground biomass. Tiller populations were greater under lax than hard cutting, though closer cutting resulted in greater green herbage accumulation. Delaying cutting until flowering was completed resulted in a subsequent depression in herbage …

Relative Productivity And Persistense Of White Clover Cultivars Under Cutting Or Continuous Stocking By Sheep, D A. Davies, M Fothergill

IGC Proceedings (1993-2023)

Perennial ryegrass-white clover (Lolium perenne-Trlfollium repens) swards of 3 clover cultivars were studied at a lowland (30 m) and upland (340 m) site in mid Wales over 3 years (1989-91). Lamb production from small-leaved Aberystwyth S 184 at 1021 kg/ha was 25% and 1191, more than from small-leaved Ac3351 and medium-leaved Grasslands Huia respectively. The relative lamb output from Huia was poorer at the upland location. Clover production, survival and morphology under a number of cutting heights and frequencies were different from those in the continuously stocked pastures. Cutting every 10 days at 2-3 cm resulted in poor clover and …

Morphological Changes In Three Clover (Trifolium Repens L.) Cultivars Under Continuous Stocking, M Fothergill, D A. Davies

IGC Proceedings (1993-2023)

Individual plant morphology of 3 white clover (Trifolium repens L.) cultivars was studied during 1990 and 1991. Seasonal shifts were demonstrated by all cultivars towards a higher proportion of less complex plants from winter to mid summer. Over the latter half of the year the population tended lo return towards its original distribution. Seasonal fluctuations in stolon dry weight/plant and root number/plant were also identified, with the small-leaved Ac3351 maintaining a greater stolon OW/plant than Aberystwyth S184 and Grasslands Huia during 1990. Ac3351 and S184 also maintained a larger root number/plant over this period. However, no significant differences were detected …

Response To Defoliation Of Tall Fescue, H Tavakoli, J Hodgson, P D. Kemp

IGC Proceedings (1993-2023)

An experiment studying the behaviour of toll fescue (Fesutca anrundinacea Schreb,) was conducted under steady stale grazing on a sward dominated by this plant. The swards were grazed lo maintain a surface height of 30-40 mm (H), 50-60 mm (M) and 90-100 mm (L). These treatments were applied on swards with and without white clover (Trifolium repens L.) from November 1990 to April 1991. Results showed that leaf growth decreased as the severity of grazing increased. Tiller number was less under H grazing than under M or L grazing, but tiller size remained constant over time in this …

Carbon Isotope Discrimination And Productivity Of Yellow-Flowered Falcata Alfalfa Clonesj, J A. Morgan, D R. Lecain, C E. Townsend

IGC Proceedings (1993-2023)

Although genetic variation for water•use efficiency has been identified in a number of plant species, progress to genetically increase this trait has been limited, largely owing to the difficulty in evaluating numerous genotypes. Eleven clones of yellow-flowered, falcata-type alfalfa (Medicago saliva L. ssp. falcata (L.) Arcangeli} were grown in the greenhouse under 2 watering regimes, and in space•planted field plots for 2 years. Clonal variation was found in all 4 environments for plant yield and shoot carbon isotope discrimination (A), a trait believed to estimate plant water use efficiency. Generally non­significant correlations between A and forage yield suggest that …

Adaptation Of Sainfoin Cultivars And Lucerne To Water Stress, S R. Mir Hosseini, P D. Kemp, D J. Barker, J Hodgson

IGC Proceedings (1993-2023)

Sainfoin ( Onobrychis viciifolia Scop.) is of particular interest as a pasture crop because it is a productive legume in dry areas but does not induce bloat in ruminant animals. In this study 3·sainfoin cultivars (Fakir, Melrose and 035) and l lucerne (Medicago saliva L.) cultivar Grasslands Oranga were compared during a drying phase when water was withheld once; flowering began. A randomised complete block design with 4 replicates' was used. Transpiration rate (Tr) declined as volumetric soil water content (VSWC) was reduced. Stomata! resistance (Rs) increased and relative ivater content (RWC) decreased when VSWC decreased. Critical VSWC for …

Phytochrome Control Of Assimilate Partitioning In White Clover, Ch Robin, C Varlet-Grancher, F Gastal, A Guckert

IGC Proceedings (1993-2023)

Experiments were conducted in controlled conditions to examine the influences of phytochrome on assimilate partitioning between stolons and branches and to determine the effects on plant moq>hogcncsis in white clover (Trifolium repens L.). Far-red (FR) irradiated plants partitioned more 14C-assimilates to petioles of both the main stolon and branches and less to the nodulated COOis than did control plants. Results clearly demonstrated that FR-irradiated plants developed longer petioles and long internodes. Moreover, the branching rate decreased, which induced a lower portion of dry weight allocated to branches. However, the sink strength of the branches which were developing remained …

Influence Of Rooting On Stolon Branching In White Clover, M Jones, N R. Sackville Hamilton

IGC Proceedings (1993-2023)

The relationship between rooting and branching in stolons of white clover (Trifolium repens L.) was investigated in a field experiment, Half of a group of stolons was allowed to develop roots naturally, while for the other half root establishment was prevented by severing young roots before they made contact with the soil. Prevention of root establishment did not affect the numbers of branches which developed on nodes produced during the experiment, and it stimulated of branching on nodes which were already present. This result was unexpected on the basis of earlier observations of stolon growth and suggests that the …

Accumulation Of Dry Matter, Protein And Total Available Carbohydrate In Berseem Under Different Cutting Regimes, P Martinello, G De Santis, A Iannucci, N Di Fonzo

IGC Proceedings (1993-2023)

The effect of different cutting regimes on physiology and morphology of aerial parts and roots in 6 bcrseem (Trifolium alexadrium L.) genotypes was evaluated. Observations were carried out on individual plants at 4 stages of development: fourth and eighth internode elongation, early flowering and physiological seed maturity. The results showed that the genotypes were characterised by highest values of dry matter in the aerial and root parts at the early flowering stage. Variability among genotypes was observed.

Seasonal Growth Rhythms In Lucerne, C Poisson, G Genier, A Canal, P Guy, A Porcheron

IGC Proceedings (1993-2023)

The repartition of dry matter production of lilcerne (Medicago saliva) through the year is of great interest. A 3-year experiment began in 1990 to distinguish different rhythms of regrowth. Eighteen genotypes of very diverse geographic origins exhibiting great differences of winter dormancy were studied in a multisite experiment. Two different non-destructive methods were used to describe accurately leaf area index evolution: red far/red light ratio (660 nm/730 nm), and indirect measurement of LAI {LI-COR 2000); stem height and dry matter yield were regularly recorded. Important differences in summer and autumn behaviour leading to different sigmoid growth curves wece …

Inherent And Realized Potential Of Axillary Buds Of White Clover In Field Populations, P.C D. Newton, M.J M. Hay

IGC Proceedings (1993-2023)

Fewer than 10% of while clover (Trifolium repens L.) axillary buds form established branches in grazed swards. In order to understand the mechanisms controlling his large loss of growth potential we have charted the potential fates a bud may meet. Each step in this flow chart offers the possibility for a loss of branching potential. We consider the factors that may be important in determining the fates of buds and highlight in particular the heavy losses of viable buds at a young age and propose that different factors may control branch initiation and branch establishment.

Prediction Of Plant Mortality Under Grazing- A Conceptual Approach, J J. Mott, G K. Mckeon, K A. Day

IGC Proceedings (1993-2023)

Based on the concept of biological thresholds, there is growing acceptance 0£ the importance o£ episodic events in the determination of rangeland condition trend. The variable rainfall occurring within Australian rangelands means that overstocking during droughts is a major cause of these Australian rangeland vegetation complexes exceeding these thresholds. Recently plant production models and simplistic estimates of the relationship between animal utilisation and plant mortality became available. Accurate estimates will be developed only with the incorporation of a sound mechanistic understanding of the relationship between utilisation of forage and plant mortality for different conditions of species and soils. Detailed studies …

Canopy Structure And Forage Production Of Lolium Rididum Gaudin As Influenced By The Frequency Of Defoliation, P P. Roggero, A Franca, M Sitzia, S Caredda

IGC Proceedings (1993-2023)

An experiment was conducted in Sardinia to develop an appropriate rotational grazing management regime in spring for an ecotype of annual ryegrass (Lolium rigidum Gaudin). Three intermittent defoliation treatments were compared using sward surface height (10, 15 or 20 cm) to determine time of cutting. Forage dry matter yield, tiller population density, LAI, vertical distribution of plant tissues and other related characteristics were measured. Cutting when sward reached 10 cm resulted In significantly lower yields but a better canopy structure (denser sward, higher percentage of leaves in the bottom layers, higher leaf: sheath ratio) than the other treatments. The …

Physiological Response And Leaf Production Of Two C4 Grasses After Small Rainfall Events, A J. Norman, T L. Thurow, C A. Taylor Jr

IGC Proceedings (1993-2023)

The response of plant water status and leaf production of sideoats grama (Bouteloua curtipendula Michx.) and curly mesquite (Hilaria belangeri Steud.) to application of 10 mm of water were studied in 6 continuous weighing lysimeters near Sonora, Texas, USA.: Transpiration, stomata! conductance, xylem water potentials and leaf production were measured foe both species. Soil water content was monitored in each lysimeter. The 10-mm simulated rainfall events improved plant water status regardless of prior soil water· content.' The transpiration rate for both species was similar. Stomata! conductance' of B. c1irtipe11d11/a responded faster after the simulated rainfall events. More favorable …

Effects Of Cutting Dates In Primary Growth, Water Soluble Carbohydrate Content And Nitrogen Fertilization On Regrowth Of Perennial Ryegrass, W Pohlmann, U Simon

IGC Proceedings (1993-2023)

In a field experiment, an early• and a late-maturing cultivar of perennial ryegrass were cut during the primary growth in 6-weekly intervals starting when the early cultivar (Lolium perenne L.) reached stage of growth 31 (Simon & Park 1983, Proceedings XIV IGC), at 2 levels of nitrogen fertilisation. Dry mailer yield (DMY) in the regrowth was determined 4 weeks after defoliation in the primary growth. DMY in the regrowth decreased with delayed cutting in the primary growth. No significant correlation existed between the content of water soluble carbohydrates (WSC) in 1he stubble at the time of defoliation in the …

Effect Of Row Spacing And Sowing Rate On Establishment Of Lucerne Cv. Grasslands Oranga, M Askarian, J G. Hampton

IGC Proceedings (1993-2023)

Studies on the effects of various row spacings and sowing rates on the establishment of autumn-sown lucerne (Medicago saliva L) cv. Grasslands Oranga were carried out in a split-plot experiment at Massey University Palmerston North, New Zealand. Seed was sown on 15 March 1991 at 1, 3, 6 and 12 kwha at row spacings of 15, 30, 45 and 60 cm. Seedling establishment increased as sowing rate and row spacing increased, but numbers of seedlings were not directly proportional to the number of seeds sown. The percentage establishment 6 months after sowing was significantly higher atthe lowest sowing rate. …