Physical Sciences and Mathematics Commons^™

Belowground Meristem Populations As Regulators Of Grassland Dynamics, Harmony J. Dalgleish, D. C. Hartnett

IGC Proceedings (1977-2023)

Studies of plant populations are critical for linking organism to ecosystem-level phenomena and for understanding mechanisms driving responses to global change. In perennial grasslands, the below-ground population of meristems (the bud bank) plays a fundamental role in local plant population recruitment, persistence and dynamics. We explore two aspects of the bud bank in North American grasslands. It has been hypothesized that low variability in arid biomes is explained by meristem limitation, which constrains responses to pulses of high resource availability. Our research tests this hypothesis by comparing bud-bank populations across six sites in the United States that vary 3-fold in …

The Impact Of Vegetation Structure And Spatial Heterogeneity On Invertebrate Biodiversity Within Upland Landscapes, L. Cole, M. L. Pollock, D. Robertson, J. P. Holland, D. I. Mccraken

IGC Proceedings (1977-2023)

Livestock grazing influences vegetation structure and composition at both the patch and wider landscape scale (Milne et al., 1998), and this may have effects on upland invertebrate communities, which in turn influence bird abundance and distribution (Fuller & Gough, 1999; Cole et al., 2002). Of particular importance are open grasslands and wet flushes where invertebrates are abundant and more accessible to birds. However, there have been few studies of invertebrates associated with upland habitats, and most of these have focused on heather moorland, blanket bog, or very fine-scaled structure within grasslands (Dennis et al. 1997; 1998; 2001). This …

Attenuated Skeletal Muscle Metabolism Explains Blunted Reactive Hyperemia After Prolonged Sitting, Cody Anderson, Elizabeth Pekas, Michael Allen, Song-Young Park

UNO Student Research and Creative Activity Fair

Introduction: Although reduced post-occlusive reactive hyperemia (PORH) after prolonged sitting (PS) has been reported as impaired microvascular function, no specific mechanism(s) have been elucidated. One potential mechanism, independent of microvascular function, is that an altered muscle metabolic rate (MMR) may change the magnitude of PORH by modifying the oxygen deficit achieved during cuff-induced arterial occlusions. We speculated that if MMR changes during PS, this may invalidate current inferences about microvascular function during PS. Objective: Therefore, the objective of this study was to examine if peripheral leg MMR changes during PS and to ascertain whether the change in the oxygen deficit …

Problem Of The Week: A Student-Led Initiative To Bring Mathematics To A Broader Audience, Jordan M. Sahs, Brad Horner

UNO Student Research and Creative Activity Fair

Problem of the Week (POW!) is a weekly undergraduate mathematics competition hosted by two graduate students from the UNO Math Department. It started with the goal to showcase variety, creativity, and intrigue in math to those who normally feel math is dry, rote, and formulaic. Problems shine light on both hidden gems and popular recreational math, both math history and contemporary research, both iconic topics and nontraditional ones, both pure abstraction and real-world application. Now POW! aims to increase availability and visibility in Omaha and beyond. Select problems from Fall 2021 to Spring 2023 are highlighted here: these received noteworthy …

Healthcare Facilities: Maintaining Accessibility While Implementing Security, Ryan Vilter

UNO Student Research and Creative Activity Fair

In the wake of the Tulsa, Oklahoma hospital shooting in the summer of 2022, it was made clear that more security needed to be implemented in healthcare facilities. As a result, I inquired: What is the happy balance for healthcare facilities to maintain their accessibility to the public while also implementing security measures to prevent terrorist attacks? With that base, I give recommendations in the areas of cybersecurity, physical infrastructure, and physical and mental health, based off the existing literature and data gathered from terrorist attacks against hospitals over several decades.

The Effects Of Demographics And Risk Factors On The Morphological Characteristics Of Human Femoropopliteal Arteries, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Background: Disease of the lower extremity arteries (Peripheral Arterial Disease, PAD) is associated with high morbidity and mortality. During disease development, the arteries adapt by changing their diameter, wall thickness, and residual deformations, but the effects of demographics and risk factors on this process are not clear.

Methods: Superficial femoral arteries from 736 subjects (505 male, 231 female, 12 to 99 years old, average age 51±17.8 years) and the associated demographic and risk factor variables were used to construct machine learning (ML) regression models that predicted morphological characteristics (diameter, wall thickness, and longitudinal opening angle resulting from the …

Time Evolution Is A Source Of Bias In The Wolf Algorithm For Largest Lyapunov Exponents, Kolby Brink, Tyler Wiles, Nicholas Stergiou, Aaron Likens

UNO Student Research and Creative Activity Fair

Human movement is inherently variable by nature. One of the most common analytical tools for assessing movement variability is the largest Lyapunov exponent (LyE) which quantifies the rate of trajectory divergence or convergence in an n-dimensional state space. One popular method for assessing LyE is the Wolf algorithm. Many studies have investigated how Wolf’s calculation of the LyE changes due to sampling frequency, filtering, data normalization, and stride normalization. However, a surprisingly understudied parameter needed for LyE computation is evolution time. The purpose of this study is to investigate how the LyE changes as a function of evolution time …

Toward A Simulation Model Complexity Measure, J. Scott Thompson, Douglas D. Hodson, Michael R. Grimaila, Nicholas Hanlon, Richard Dill

Faculty Publications

Is it possible to develop a meaningful measure for the complexity of a simulation model? Algorithmic information theory provides concepts that have been applied in other areas of research for the practical measurement of object complexity. This article offers an overview of the complexity from a variety of perspectives and provides a body of knowledge with respect to the complexity of simulation models. The key terms model detail, resolution, and scope are defined. An important concept from algorithmic information theory, Kolmogorov complexity, and an application of this concept, normalized compression distance, are used to indicate the possibility of measuring changes …

Studies On Bonding, Syntheses, And Applications Of Diarylhalonium Compounds, Shubhendu Karandikar

Dissertations and Theses

Organic compounds containing functionalized benzenoid rings have found tremendous applications in pharmaceuticals, agrochemicals, commodity chemicals, and beyond. As a result, development of methods for the synthesis of functionalized benzenoid rings has gained much attention from the synthetic community. Although many transition-metal mediated methods to functionalize benzenoid rings are known, there has been an upsurge of activity in developing protocols for decoration of benzenoid cores promoted by p-block elements. This excitement stems from the sustainability of earth-abundant elements and unique reactivity patterns observed within the p-block. Among these, transformations promoted by hypervalent halogen compounds, and especially, the diarylhalonium salts are very …

Assessment Of Air Pollution Levels During Sugarcane Stubble Burning Event In La Feria, South Texas, Usa, Sai Deepak Pinakana, Edward Robles, Esmeralda Mendez, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Agricultural stubble burning is the third largest source of air pollution after vehicular and industrial emissions. Fine particulate matter (PM2.5), volatile organic compounds (VOCs), carbon monoxide (CO), nitrogen dioxide (NO2), and black carbon (BC) are some of the pollutants emitted during such burning events. The Lower Rio Grande Valley (RGV) region of South Texas is a major hub of agricultural activity, and sugarcane farming is one of them. Unfortunately, this activity results in episodic events of high air pollution in this low-resourced, Hispanic/Latino majority region of the U.S.–Mexico border. This study presents results from a sugarcane site in La Feria, …

Fraud Pattern Detection For Nft Markets, Andrew Leppla, Jorge Olmos, Jaideep Lamba

SMU Data Science Review

Non-Fungible Tokens (NFTs) enable ownership and transfer of digital assets using blockchain technology. As a relatively new financial asset class, NFTs lack robust oversight and regulations. These conditions create an environment that is susceptible to fraudulent activity and market manipulation schemes. This study examines the buyer-seller network transactional data from some of the most popular NFT marketplaces (e.g., AtomicHub, OpenSea) to identify and predict fraudulent activity. To accomplish this goal multiple features such as price, volume, and network metrics were extracted from NFT transactional data. These were fed into a Multiple-Scale Convolutional Neural Network that predicts suspected fraudulent activity based …

Self-Learning Algorithms For Intrusion Detection And Prevention Systems (Idps), Juan E. Nunez, Roger W. Tchegui Donfack, Rohit Rohit, Hayley Horn

SMU Data Science Review

Today, there is an increased risk to data privacy and information security due to cyberattacks that compromise data reliability and accessibility. New machine learning models are needed to detect and prevent these cyberattacks. One application of these models is cybersecurity threat detection and prevention systems that can create a baseline of a network's traffic patterns to detect anomalies without needing pre-labeled data; thus, enabling the identification of abnormal network events as threats. This research explored algorithms that can help automate anomaly detection on an enterprise network using Canadian Institute for Cybersecurity data. This study demonstrates that Neural Networks with Bayesian …

Deep Learning For Online Fashion: A Novel Solution For The Retail E-Commerce Industry, Zachary O. Harris, Gowtham G. Katta, Robert Slater, Joseph L. Woodall Iv

SMU Data Science Review

The online shopping experience for clothing can be further enhanced by implementing Deep Learning techniques, such as Computer Vision and personalized recommendation systems. Automation, as a principle, can be applied to solving problems surrounding efficacy, efficiency, and security. It also provides a layer of abstraction for the user during the online shopping experience. This research aims to apply Deep Learning methods and principles of automation to augment the e-commerce fashion market in a novel way. After using these methods, it was found that Convolutional Autoencoders and Item-to-Item Based Recommenders may be used to accurately and precisely recommend articles of clothing …

Towards A Comparative Map Of White Clover (Trifolium Repens) And Barrel Medic (Medicago Truncatula), M. Febrer, G. Jenkins, M. T. Abberton, D. Milbourne

IGC Proceedings (1977-2023)

Grassland is of pivotal importance to the Irish agricultural industry. This dependence of grass is reflected in the large proportion of land area under grass, approx. 80% of the total land acreage in Ireland. The presence of white clover (Trifolium repens L.) in grassland significantly improves the overall nutritional value of the forage by increasing the relative amounts of nitrogen present. Genetic improvement of white clover through breeding of varieties should increase the productivity of grasslands. Advances in plant biotechnology offer the possibility of developing tools that will radically enhance our ability to breed improved plant varieties. The objective …

Role Of The Banyuls(Ban) Gene From Arabidopsis Thaliana In Transgenic Alfalfa Expression Of Anthocyanins And Proanthocyanidins, S. M. Hesamzadeh Hejazi, Sergio Arcioni, F. Paolocci

IGC Proceedings (1977-2023)

Condensed tannins (CTs) are flavonoid oligomers, many of which have beneficial effects on animal (bloat safe) and human health. The BAN gene encodes anthocyanidin reductase (ANR), an enzyme proposed to convert anthocyanidins to their corresponding 2,3-cis-flavan-3-ols (Xie et al., 2003). Ectopic expression of BAN in Alfalfa transgenic foliage results in accumulation of CTs. Thus, it has been assumed that the BAN gene also acts in starter units for the condensation of tannins in Alfalfa.

Clover Astra: A Web-Based Resource For Trifolium Est Analysis, G. C. Spangenberg, T. Sawbridge, E. K. Ong, C. G. Love, T. A. Erwin, E. G. Logan, D. Edwards

IGC Proceedings (1977-2023)

White clover (Trifolium repens L.) is a major temperate forage legume.

Controlled Flowering Project For Lolium Perenne At Agresearch: An Overview, I. Kardailsky, B. Veit, N. Forester, M. Gagic, K. Richardson, Marty J. Faville, G. Bryan

IGC Proceedings (1977-2023)

Ryegrass (Lolium perenne) is an important forage crop in New Zealand. The work presented here has the goal of developing a system for complete and arbitrary control of the transition from vegetative to floral development. For this, we have pursued an integrated approach utilising genomics with both forward and reverse genetics. Like other model plants, photoperiodic and vernalization pathways are presumed to be operating in ryegrass and control the activity of the meristem identity/floral patterning genes. The candidate gene approach targeting the photoperiodic pathway is described in an accompanying abstract (Gagic et al.). Other candidate genes include …

Monitoring Of Gene Expression Profiles And Identification Of Candidate Genes Involved In Drought Tolerance In Festuca Mairei With Cdna-Aflp, J. P. Wang, S. S. Bughrara

IGC Proceedings (1977-2023)

Drought stress is one of the most complex environmental constraints on plants. Response of plant to drought stress is manifested by various changes in physiological and metabolic processes, which are reflected at the molecular level. cDNA-amplified fragment length polymorphism (cDNA-AFLP) is a high-throughput transcript profiling technique for temporal and spatial gene expression analysis (Bachem et al., 1996). To understand the molecular genetic basis of drought tolerance of grasses, we applied the cDNA-AFLP procedure to identify the genes responding to drought stress of Festuca mairei (Fm), which showed a xeriphytic adaptation (Marlatt et al., 1997).

Gene Discovery And Molecular Dissection Of Fructan Metabolism In Perennial Ryegrass (Lolium Perenne), J. Chalmers, A. Lidgett, X. Johnson, K. Terdich, N. Cummings, Y. Y. Cao, K. Fulgueras, M. Emmerling, T. Sawbridge, E. K. Ong, A. Mouradov, G. C. Spangenberg

IGC Proceedings (1977-2023)

Fructans are the main soluble carbohydrate stored in up to a third of the vegetation of the earth, including the economically important temperate grasses. Fructans are polymers of fructose attached to a sucrose precursor. Perennial ryegrass (L. perenne L.) accumulates fructans of the inulin series, inulin neoseries and levan neoseries. Four enzymes are required to produce fructans of this profile: 1-SST (sucrose:sucrose 1- fructosyltransferase), 1-FFT (fructan:fructan 1-fructosyltransferase), 6G-FFT (6-glucose fructosyltransferase) and 6-FFT (fructan:fructan 6-fructosyltransferase) or 6-SFT (sucrose:fructan 6-fructosyltransferase) (Figure 1). Fructan biosynthetic enzymes have evolved from invertases and thus it is argued that fructan metabolism is an extension …

Isolation And Characterization Of A Cbf Gene From Perennial Ryegrass (Lolium Perenne L.), Y. Xiong, S. Fei

IGC Proceedings (1977-2023)

Maximum freezing tolerance of many temperate plant species is achieved after exposure to a period of non-freezing low temperatures, a phenomenon called “cold acclimation”. Multiple mechanisms appear to operate in conferring freezing tolerance in plants. The discovery of a class of transcription factor genes, CBF genes (C-repeat binding factor), in Arabidopsis demonstrated that CBF genes can serve as ‘Master switches’ to activate downstream cold-related (COR) genes during cold-acclimation (Liu et al., 1998). They act by binding to the core sequence (CCGAC) which is present in COR genes and thus activate the expression of COR genes and enhance …

Phenotypic Variation Within Local Populations Of Meadow Fescue Shows Significant Associations With Allele Frequencies At Aflp Loci, S. Fjellheim, Å. B. Blomlie, P. Marum, O. A. Rognli

IGC Proceedings (1977-2023)

To identify markers useful for Marker Assisted Selection (MAS), mapping families are usually constructed and used for Quantitative Trait Loci (QTL) mapping. Association mapping offers an alternative strategy for marker development using already characterized germplasm, preferably from natural populations. Simultaneous phenotypic and molecular screening of gene bank accessions can reveal associations between molecular marker alleles and phenotypic traits, and lead to a more targeted construction of mapping families for fine-mapping. In this investigation, we combine molecular (AFLP) and phenotypic data of 15 Norwegian local populations and 5 Nordic cultivars in order to identify markers associated with phenotypic traits of interest.

Diversity Of Diet Composition Decreases With Conjoint Grazing Of Cattle With Sheep And Goats, A. M. Nicol, M. B. Soper, A. Stewart

IGC Proceedings (1977-2023)

Conjoint or mixed grazing can affect the diet selected by each species (Nicol & Collins, 1990). Diet similarity coefficients are often used to compare pairs of diets (Krebs, 1999). However this approach is awkward when a number of contrasts are required in a multifactorial comparison. Species diversity is a descriptor of a particular environment. Many models provide an estimate of species diversity, the most common of these being a log-normal distribution (Tokeshi, 1996). We tested whether this model could be applied to dietary components selected from a pasture, and thus provide a coefficient of dietary diversity for the individual diets …

A Simple Vegetation Criterion (Ndf Content) May Account For Diet Choices Of Cattle Between Forages Varying In Maturity Stage And Physical Accessibility, Cécile Ginane, R. Baumont

IGC Proceedings (1977-2023)

The management of extensively grazed pastures requires an understanding and prediction of the diet choices of herbivores grazing on vegetation that is qualitatively (maturity stage) and quantitatively (biomass, sward height) heterogeneous. The Optimal Foraging Theory (OFT, Stephens & Krebs, 1986), bases its predictions on the relative energy intake rate (EIR) of forages. However, as EIRs are difficult to assess at pasture and are subject to wide intra- and inter-individual variations, another vegetation criterion was sought (accessibility, quality), by-passing the animal's influence, to predict cattle diet choices quantitatively.

Spatial Scale Of Heterogeneity Affects Diet Choice But Not Intake In Beef Cattle, S. Mark Rutter, J. E. Cook, K. L. Young, R. A. Champion

IGC Proceedings (1977-2023)

Previous research has shown that sheep (Champion et al., 1998) and dairy cattle (Nuthall et al., 2000) have a partial preference for clover of 70%, and achieve higher daily intakes when offered grass and clover as separate but adjacent monocultures compared with animals grazing mixed swards. This intake benefit could be utilised to increase intake and production on farms by grazing from adjacent strips of the two herbages. This study aimed to establish the minimum strip width required to achieve the benefits of monocultures.

Is Biodiversity Declining In The Traditional Haymeadows Of Skye And Lochalsh, Scotland?, G. E. D. Tiley, D. G. L. Jones

IGC Proceedings (1977-2023)

Species-rich haymeadows have developed on crofts in the Isle of Skye and Lochalsh Districts of north-west Scotland as a result of a century or more of traditional land use. This has involved long rotations of late cutting for hay with aftermath grazing by cattle and short breaks for cropping. The traditional haymeadows are increasingly coming under threat from changes taking place in the countryside. A survey of the main haymeadows still remaining in Skye and Lochalsh was carried out during 2003 to assess the current botanical composition, management and conservation value, and to compare with earlier surveys.

Alternative Land Use Options For Philippine Grasslands: A Bioeconomic Modeling Approach Using The Wanulcas Model, D. B. Magcale-Macandog, E. Abucay, P. A. B. Ani

IGC Proceedings (1977-2023)

In the Philippines, pure grasslands occupy 1.8 million ha and another 10.8 million ha (33% of the country’s total land area) is under extensive cultivation mixed with grasslands and scrub. Most of these grasslands are under-utilised and dominated by Imperata cylindrica. Imperata grasslands generally represent areas of degraded soils that are acidic, low in organic matter and susceptible to erosion. However, conversion of these grassland areas into upland farms planted to annual crops and perennial trees is proliferating at a fast rate. This is triggered by the interacting factors of rapidly increasing population, the system of landholding, scarcity of …

Forage Development In The Nepal Mid-Hills: New Perspectives, A. D. Robertson

IGC Proceedings (1977-2023)

Nepali hill farming communities are typically poor and remote, and are currently severely affected by conflict. The challenge is to define simple approaches which can generate results within this context. Livestock are central to livelihoods and to the sustainability of farming, with rain-fed agriculture dependent on inputs of manure-based compost. Stall feeding has increased dramatically with the adoption of community forestry and general preclusion of grazing. A broad landscape approach to forage development is increasingly being adopted, with concurrent on-farm interventions, such as intercropping and back-yard forage, and off-farm interventions, such as landslide stabilisation with forages, development of forest understory, …

How To Simplify Tools For Natural Grassland Characterisation Based On Biological Measures Without Losing Too Much Information?, P. Ansquer, P. Cruz, J. P. Theau, E. Lecloux, M. Duru

IGC Proceedings (1977-2023)

In marginal areas, such as the Pyrenees, natural grasslands are the only available resource for livestock feeding. Despite this, there is a lack of simple and efficient tools for advisers to aid the management of the complex vegetation of these grasslands. Therefore, we tested an approach derived from functional ecology, to construct such tools: using biological traits to inform on the agronomic characteristics and the way farmers’ practices act on them (Ansquer et al., 2004). Nevertheless, the required protocol of measurement is still time-consuming and difficult. In this paper, we test different ways of simplifying this protocol by reducing …

Herders And Wetland Degradation In Northern Cameroon, E. Tedonkeng Pamo, F. Tendonkeng, J. R. Kana

IGC Proceedings (1977-2023)

Livestock rearing in Northern Cameroon is carried out under two majors systems: the nomadic and the transhumance production systems (Pamo & Pamo, 1991). Nomadism is the practice of wandering from place to place, while transhumance involves seasonal displacement of flocks from one area to another by herders. These production systems involved large grazing areas, which may encompass different ecosystems. The Yaére, the only wetland of the northern Cameroon, is the major dry season grazing lands for livestock and wildlife. The main characteristic of this wetland is that the whole area is excluded from grazing during the growing season as a …

New Far-Infrared Laser Frequencies Generated By Ch3cn, Cd3cn, 13ch3i, Cd3i, And 13cd3i, Michael Jackson

All Faculty Scholarship for the College of the Sciences

Heterodyne techniques have been used to experimentally determine, for the first time, the frequencies for nineteen laser emissions ranging from 264 to 984 GHz. These laser emissions were generated by optically pumping either CH₃CN, CD₃CN, ¹³CH₃, CD₃I, or ¹³CD₃I with a CO₂ laser. This includes the newly discovered 566.325-μ m laser emission from optically pumped ¹³CD₃I. The fractional uncertainties with which these frequencies were experimentally determined, up to ± 5 × 10^− 7, were of sufficient accuracy to confirm or revise …