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Articles 31021 - 31050 of 294419

Full-Text Articles in Physical Sciences and Mathematics

Comparative Life Cycle Assessment Of Copper Production, Xiaohan Wu Mar 2024

Comparative Life Cycle Assessment Of Copper Production, Xiaohan Wu

Graduate Industrial Research Symposium

Copper demand will surge significantly in the context of global renewable energy technology implementation, but its production is an energy-intensive process. It is crucial to choose the best production method to reduce environmental damage in terms of the enormous copper supply. This research develops a multi-criteria life cycle assessment model for the three main copper production routes- pyrometallurgy, hydrometallurgy, and bioleaching. We complied material and energy flow data to assess each route's life cycle greenhouse gas (GHG) emissions, cost, and resource efficiency. Results indicate bioleaching emits the least GHG emissions (4.09 kg-CO2 eq/kg copper) among the three routes. Hydrometallurgy is …

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Characterization Of Biological Particles Using An Integrated Hyperspectral Imaging And Machine Learning, Kaeul Lim, Arezoo Ardekani Mar 2024

Characterization Of Biological Particles Using An Integrated Hyperspectral Imaging And Machine Learning, Kaeul Lim, Arezoo Ardekani

Graduate Industrial Research Symposium

Hyperspectral imaging (HSI) is a promising modality in medicine with many potential applications. This study focuses on developing a label-free lipid nanoparticle characterization method using a convolutional neural network (CNN) analysis of HSI images. The HSI data, hypercube, consists of a series of images acquired at different wavelengths for the same field of view, providing continuous spectra information for each pixel. Three distinct liposome samples were collected for analysis. Advanced image preprocessing and classification methods for HSI data were developed to differentiate liposomes based on their material compositions. Our machine learning-based classification method was able to distinguish different liposome types …

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Sepsis Treatment: Reinforced Sequential Decision-Making For Saving Lives, Dipesh Tamboli, Jiayu Chen, Kiran Pranesh Jotheeswaran, Denny Yu, Vaneet Aggarwal Mar 2024

Sepsis Treatment: Reinforced Sequential Decision-Making For Saving Lives, Dipesh Tamboli, Jiayu Chen, Kiran Pranesh Jotheeswaran, Denny Yu, Vaneet Aggarwal

Graduate Industrial Research Symposium

Sepsis, a life-threatening condition triggered by the body's exaggerated response to infection, demands urgent intervention to prevent severe complications. Existing machine learning methods for managing sepsis struggle in offline scenarios, exhibiting suboptimal performance with survival rates below 50%. Our project introduces the "PosNegDM: Reinforcement Learning with Positive and Negative Demonstrations for Sequential Decision-Making" framework utilizing an innovative transformer-based model and a feedback reinforcer to replicate expert actions while considering individual patient characteristics. A mortality classifier with 96.7% accuracy guides treatment decisions towards positive outcomes. The PosNegDM framework significantly improves patient survival, saving 97.39% of patients and outperforming established machine learning …

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Online Class-Incremental Learning For Real-World Food Image Classification, Siddeshwar Raghavan, Jiangpeng He, Fengqing Zhu Mar 2024

Online Class-Incremental Learning For Real-World Food Image Classification, Siddeshwar Raghavan, Jiangpeng He, Fengqing Zhu

Graduate Industrial Research Symposium

Food image classification is essential for monitoring health and tracking dietary in image-based dietary assessment methods. However, conventional systems often rely on static datasets with fixed classes and uniform distribution. In contrast, real-world food consumption patterns, shaped by cultural, economic, and personal influences, involve dynamic and evolving data. Thus, it requires the classification system to cope with continuously evolving data. Online Class Incremental Learning (OCIL) addresses the challenge of learning continuously from a single-pass data stream while adapting to the new knowledge and reducing catastrophic forgetting. Experience Replay (ER) based OCIL methods store a small portion of previous data and …

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Modelling The "Bottom-Up" Development Pattern Of Tar Spot Disease In Corn, Brenden Lane, Joaquín Guillermo Ramírez-Gil, Carlos Góngora-Canul, Mariela Sofia Fernandez Campos, Andres Cruz-Sancan, Fidel E. Jiménez-Beitia, Alex G. Acosta-Guatemal, Wily Sic, C. D. Cruz Mar 2024

Modelling The "Bottom-Up" Development Pattern Of Tar Spot Disease In Corn, Brenden Lane, Joaquín Guillermo Ramírez-Gil, Carlos Góngora-Canul, Mariela Sofia Fernandez Campos, Andres Cruz-Sancan, Fidel E. Jiménez-Beitia, Alex G. Acosta-Guatemal, Wily Sic, C. D. Cruz

Graduate Industrial Research Symposium

In 2015, the corn-infecting pathogen Phyllachora maydis (causal agent of tar spot disease) was reported for the first time in the United States. The disease has since spread across the US, causing major yield losses. In 2021 alone, 5.88 million metric tons (231.3 million bushels) of US corn yield were lost to this disease, costing an estimated US$1.25 billion. Though fungicides can protect against these agroeconomic losses, application timing can be difficult to optimize because our understanding of tar spot dynamics is still evolving. The current view is that tar spot typically develops bottom-up through a repeating infection cycle. Because …

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A Machine Learning Model Of Perturb-Seq Data For Use In Space Flight Gene Expression Profile Analysis, Liam F. Johnson, James Casaletto, Lauren Sanders, Sylvain Costes Mar 2024

A Machine Learning Model Of Perturb-Seq Data For Use In Space Flight Gene Expression Profile Analysis, Liam F. Johnson, James Casaletto, Lauren Sanders, Sylvain Costes

Graduate Industrial Research Symposium

The genetic perturbations caused by spaceflight on biological systems tend to have a system-wide effect which is often difficult to deconvolute it into individual signals with specific points of origin. Single cell multi-omic data can provide a profile of the perturbational effects, but does not necessarily indicate the initial point of interference within the network. The objective of this project is to take advantage of large scale and genome-wide perturbational datasets by using them to train a tuned machine learning model that is capable of predicting the effects of unseen perturbations in new data. Perturb-Seq datasets are large libraries of …

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Student Perspectives On Assignment Deadline Policies In Computer Science Courses, J. Kim, Christian Murphy Mar 2024

Student Perspectives On Assignment Deadline Policies In Computer Science Courses, J. Kim, Christian Murphy

Computer Science Faculty Works

While the COVID-19 pandemic encouraged higher education to be more flexible, there is now growing uncertainty regarding the usefulness of flexibility as students return to in-person classes, particularly in fast-paced, rigorous fields such as Computer Science (CS). A big part of providing flexibility in education is through assignment deadlines. On one hand, flexible deadline policies may reduce student stress, help students face unexpected circumstances, and improve student learning; on the other, too much flexibility may lead to procrastination and poor time management. In order to help CS instructors make informed decisions when choosing an assignment deadline policy, we compared student …

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Experiences Of Undergraduate Computer Science Students Living With Mental Health Conditions, J. Ji, Christian Murphy, B. Blaser, J. Akullian Mar 2024

Experiences Of Undergraduate Computer Science Students Living With Mental Health Conditions, J. Ji, Christian Murphy, B. Blaser, J. Akullian

Computer Science Faculty Works

Along with the growing number of students with disabilities in higher education comes an opportunity to explore the difficulties they experience, especially in the post-pandemic era, as well as how to better support them, thus making post-secondary education more inclusive. A considerable amount of research has been done in providing accommodation for students with physical disabilities, but other hindrances to accessibility such as mental health conditions are prone to be overlooked, perhaps in part due to the stigmatization and subjective invisibility of this topic, specifically in rigorous, competitive fields such as Computer Science (CS). In order to bridge this gap, …

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Learning About Ai: Level Up Your Skills Without Overwhelming Your Mind, Jennifer Freer, Lara Nicosia Mar 2024

Learning About Ai: Level Up Your Skills Without Overwhelming Your Mind, Jennifer Freer, Lara Nicosia

Presentations and other scholarship

OpenAI and deep learning and neural networks, oh my!  The swiftly developing landscape of artificial intelligence, combined with its rapid integration into our work and personal lives, can feel confusing and overwhelming.  This session will help you think about AI in your own work and plan your own personal AI learning journey, while also providing thoughtful recommendations on how both you and your users can get started.  The presenters will discuss common terminology, user-friendly resources for understanding AI, questions to ask when exploring AI tools, and ideas on how to start building your own knowledge on this topic.  The information …

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2024 March 7 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University Mar 2024

2024 March 7 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

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Development Of Bifunctional Peptides As Scaffolds For Bifunctional Catalysis And A Novel Method Of Peptide Stapling Using Squaric Esters, Adam X. Wayment Mar 2024

Development Of Bifunctional Peptides As Scaffolds For Bifunctional Catalysis And A Novel Method Of Peptide Stapling Using Squaric Esters, Adam X. Wayment

Theses and Dissertations

Enzymes are some of nature's most powerful tools in chemical processes. However, their molecular complexity makes them difficult to synthesize and complicates their application in traditional organic synthesis. Peptides, a building block of enzymes, can be rapidly synthesized and have been used as a possible alternative in achieving enzyme-like catalysis. However, most peptide-based catalysts are limited in reaction-scope and are unable to incorporate traditional organic catalysts. We have designed a helical peptide scaffold capable of being functionalized with a wide variety of organocatalysts as well as transition-metal based catalysts. In order to understand how the peptide structure effects reactivity and …

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Detecting Anomalies In Time Series Using Kernel Density Approaches, Robin Frehner, Kesheng Wu, Alexander Sim, Jinoh Kim Mar 2024

Detecting Anomalies In Time Series Using Kernel Density Approaches, Robin Frehner, Kesheng Wu, Alexander Sim, Jinoh Kim

Faculty Publications

This paper introduces a novel anomaly detection approach tailored for time series data with exclusive reliance on normal events during training. Our key innovation lies in the application of kernel-density estimation (KDE) to scrutinize reconstruction errors, providing an empirically derived probability distribution for normal events post-reconstruction. This non-parametric density estimation technique offers a nuanced understanding of anomaly detection, differentiating it from prevalent threshold-based mechanisms in existing methodologies. In post-training, events are encoded, decoded, and evaluated against the estimated density, providing a comprehensive notion of normality. In addition, we propose a data augmentation strategy involving variational autoencoder-generated events and a smoothing …

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Metatranscriptomic Insights Into The Interaction Between Microcystis Blooms And Hydrogen Peroxide, Taylor L. Hancock Mar 2024

Metatranscriptomic Insights Into The Interaction Between Microcystis Blooms And Hydrogen Peroxide, Taylor L. Hancock

USF Tampa Graduate Theses and Dissertations

For this dissertation I studied the interactions of hydrogen peroxide and cyanobacterial harmful algal blooms (cHABs) dominated by Microcystis in the Caloosahatchee River, FL. Specifically, I examined how taxonomic and functional succession relates to both natural hydrogen peroxide dynamics and hydrogen peroxide added to the environment as a cHAB treatment. Chapter 2 investigated how taxonomic succession and gene expression patterns relate to blooms and associated elevated hydrogen peroxide concentrations. The results showed that gene expressions related to cyanobacterial growth were positively correlated with hydrogen peroxide. The genes identified included enzymes capable of hydrogen peroxide generation which were expressed by blooming …

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Spatial Distribution And Movement Of Atlantic Tarpon (Megalops Atlanticus) In The Northern Gulf Of Mexico, Shane A. Stephens, Michael A. Dance, Michelle Zapp Sluis, Richard J. Kline, Matthew K. Streich, Gregory R. Stunz, Aaron J. Adams, R. J. David Wells, Jay R. Rooker Mar 2024

Spatial Distribution And Movement Of Atlantic Tarpon (Megalops Atlanticus) In The Northern Gulf Of Mexico, Shane A. Stephens, Michael A. Dance, Michelle Zapp Sluis, Richard J. Kline, Matthew K. Streich, Gregory R. Stunz, Aaron J. Adams, R. J. David Wells, Jay R. Rooker

School of Earth, Environmental, & Marine Sciences Faculty Publications

Atlantic tarpon (Megalops atlanticus) are capable of long-distance migrations (hundreds of kilometers) but also exhibit resident behaviors in estuarine and coastal habitats. The aim of this study was to characterize the spatial distribution of juvenile tarpon and identify migration pathways of adult tarpon in the northern Gulf of Mexico. Spatial distribution of juvenile tarpon was investigated using gillnet data collected by Texas Parks and Wildlife Department (TPWD) over the past four decades. Generalized additive models (GAMs) indicated that salinity and water temperature played a significant role in tarpon presence, with tarpon occurrences peaking in the fall and increasing …

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Enriched Regions Of 228Ra Along The U.S. Geotraces Pacific Meridional Transect (Gp15), Willard S. Moore, Matt Charette, Paul Henderson, Doug Hammond, Nathaniel Kemnitz, Emilie Leroy, Eun Young Kwon, Mikael Hult Mar 2024

Enriched Regions Of 228Ra Along The U.S. Geotraces Pacific Meridional Transect (Gp15), Willard S. Moore, Matt Charette, Paul Henderson, Doug Hammond, Nathaniel Kemnitz, Emilie Leroy, Eun Young Kwon, Mikael Hult

Faculty Publications

The half‐life of 228Ra (5.7 years) aligns well with near‐surface and near‐bottom ocean mixing timescales. Because 228Ra is sourced from sediments, regions of enhanced activity represent water that has recently interacted with sediments on the continental margin or seabed. The GP15 meridional transect from Alaska to Tahiti along152°W encountered several regions in the upper ocean where 228Ra was enriched. These enrichments follow surface and subsurface ocean current patterns and pair with earlier measurements of 228Ra and transient radionuclides to reveal the origins of these enriched regions. An enriched region at Alaska margin stations 1–3 was sourced locally but did not …

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Instability And Quantization In Quantum Hydrodynamics, Yakir Aharonov, Tomer Shushi Mar 2024

Instability And Quantization In Quantum Hydrodynamics, Yakir Aharonov, Tomer Shushi

Mathematics, Physics, and Computer Science Faculty Articles and Research

We show how the quantum hydrodynamical formulation of quantum mechanics converts the nonlocality in the standard wave-like description of quantum systems by an instability of the quantum system, which opens the door to a new way for studying quantum systems based on known methodologies for studying the stability of fluids. As a second result, we show how the Madelung equations describe quantized energies without any external quantization conditions.

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Exploring The Design Of Low-End Technology To Increase Patient Connectivity To Electronic Health Records, Rens Kievit, Abdullahi Abubakar Kawu, Mirjam Van Reisen, Dympna O'Sullivan, Lucy Hederman Mar 2024

Exploring The Design Of Low-End Technology To Increase Patient Connectivity To Electronic Health Records, Rens Kievit, Abdullahi Abubakar Kawu, Mirjam Van Reisen, Dympna O'Sullivan, Lucy Hederman

Conference papers

The tracking of the vitals of patients with long term health problems is essential for clinicians to determine proper care. Using Patient Generated Health Data (PGHD) communicated remotely allows patients to be monitored without requiring frequent hospital visits. Issues might arise when the communication of data digitally is difficult or impossible due to a lack of access to internet or a low level of digital literacy as is the case in many African countries. The VODAN-Africa project (van Reisen et al., 2021) started in 2020 and has greatly increased the capabilities of clinics in different countries in both Africa and …

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Induction Of Neuroinflammation And Brain Oxidative Stress By Brain-Derived Extracellular Vesicles From Hypertensive Rats, Xinqian Chen, Xin Yan, Leah Gingerich, Qing Hui Chen, Lanrong Bi, Zhiying Shan Mar 2024

Induction Of Neuroinflammation And Brain Oxidative Stress By Brain-Derived Extracellular Vesicles From Hypertensive Rats, Xinqian Chen, Xin Yan, Leah Gingerich, Qing Hui Chen, Lanrong Bi, Zhiying Shan

Michigan Tech Publications

Neuroinflammation and brain oxidative stress are recognized as significant contributors to hypertension including salt sensitive hypertension. Extracellular vesicles (EVs) play an essential role in intercellular communication in various situations, including physiological and pathological ones. Based on this evidence, we hypothesized that EVs derived from the brains of hypertensive rats with salt sensitivity could trigger neuroinflammation and oxidative stress during hypertension development. To test this hypothesis, we compared the impact of EVs isolated from the brains of hypertensive Dahl Salt-Sensitive rats (DSS) and normotensive Sprague Dawley (SD) rats on inflammatory factors and mitochondrial reactive oxygen species (mtROS) production in primary neuronal …

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Identification Of Alfalfa Chromosomes Using Giemas Banding And Image Analysis Techniques, G R. Bauchan, M A. Hossain Mar 2024

Identification Of Alfalfa Chromosomes Using Giemas Banding And Image Analysis Techniques, G R. Bauchan, M A. Hossain

IGC Proceedings (1977-2023)

Chromosomes of two diploid (2n=2x=16) subspecies of Medicago sativa, ssp. caerulea and ssp. falcata, their hybrid and tetraploid (2n=4x=32) cultivated alfalfa (M. sativa, ssp. sativa) were studied. Feulgen’s staining, C- and N-banding techniques and an image analysis system were used. The chromosomes of ssp. falcata have only centromeric bands, however, a multitude of bands were observed in both the C- and N-banding pattern of ssp. caerulea and ssp. sativa enabling the precise identification of each of the eight sets of chromosomes and development of a karyotype. The differences in banding patterns between the diploid subspecies makes it possible …

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Advances In Breeding Apomictic Brachiaria In Tropical America, J W. Miles, C B. Do Valle Mar 2024

Advances In Breeding Apomictic Brachiaria In Tropical America, J W. Miles, C B. Do Valle

IGC Proceedings (1977-2023)

Prior to 1988 Brachiaria improvement was based exclusively on the collection, introduction, and evaluation of natural germplasm from Africa. Breeding programs in Brachiaria have been possible only in the past 10 years with the creation of a sexual, tetraploid B. ruziziensis cross-compatible with B. decumbens and B. brizantha. Applied Brachiaria breeding projects are underway both in Colombia (International Center for Tropical Agriculture, CIAT) and Brazil (National Centre for Beef Cattle Research - Brazilian Corporation for Agricultural Research, CNPGC/EMBRAPA). These seek to combine the broad edaphic adaptation and other desirable agronomic attributes of B. decumbens cv. Basilisk with spittlebug resistance. An …

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Evaluating Cultivars Of Subterranean Clover In Monoculture Or With Perennial Ryegrass, K F.M. Reed, S G. Clark, W M. Feely Mar 2024

Evaluating Cultivars Of Subterranean Clover In Monoculture Or With Perennial Ryegrass, K F.M. Reed, S G. Clark, W M. Feely

IGC Proceedings (1977-2023)

Over four years, sowing perennial ryegrass (Lolium perenne) with a range of subterranean clover (“sub clover”, Trifolium subterraneum) cultivars was found to reduce the yield of clover per se by 31% and increase pasture yield by 11%. For one high-producing experimental variety, the presence of grass did not reduce clover yield (P<0.001). Clover yield in monoculture plots was poorly correlated with that measured in mixed swards (r = 0.44), but clover yield (± grass) was correlated with total herbage yield (r = 0.94). Clover seed yield was not reduced by the presence of grass. However, in year 2 - but not in the establishment year - grass reduced seed weight. Irrespective of grass treatment, the new late maturing cultivar, Leura outyielded the other commercial cultivars (P<0.05). Enfield and Enfield x Daliak crosses set the most seed and regenerated with a greater density than other cultivars (P<0.05) - apart from Leura. It was concluded that the winter-active, late maturing cultivar, Leura, will compete most successfully with perennial ryegrass.

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Gene Flow In Medicago Through Somatic Hybridization, S Arcioni, F Crea, O Calderini, F Damiani, P D. Cluster, F Pupilli Mar 2024

Gene Flow In Medicago Through Somatic Hybridization, S Arcioni, F Crea, O Calderini, F Damiani, P D. Cluster, F Pupilli

IGC Proceedings (1977-2023)

The objective of this research was the characterization at both molecular and phenotypic level of three somatic hybrid plants obtained by electrofusion of protoplasts of Medicago sativa with those of M.coerulea, M.falcata and M.arborea, three Medicago species in a different relation with alfalfa. Different kinds of rearrangements including the amplification of new spacer-length variants were detected at rDNA loci in the somatic hybrids. Analysis of field performances confirmed the suitability of these plants for breeding purposes.

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Ssr- And Rapd Analysis Of A New Agropyron Repens Genotype, G Gyulai, H Ohm, I Dweikat, E Kiss, H Sharma, J Janovszky, L Heszky Mar 2024

Ssr- And Rapd Analysis Of A New Agropyron Repens Genotype, G Gyulai, H Ohm, I Dweikat, E Kiss, H Sharma, J Janovszky, L Heszky

IGC Proceedings (1977-2023)

SSR-(single sequence repeat), and RAPD (randomly amplified polymorphic DNA) primer generated DNA fingerprints were used to distinguish a new genotype of quackgrass from its original type of Agropyron repenes L. Beauv. (= Elytrigia repens). Products of polymerase chain reactions (PCR) were separated by agarose (AGE) and denaturing gradient gel electrophoresis (DGGE). Although, both kinds of primers were found to be polymorphic, the microsatellite primer with sequence of 5í-AC(GACA)4-3í generated distinguishing fingerprints in the two types of quackgrasses. This result gives genetic evidence for the new genotype of quackgrass.

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Screening Ryegrass Cultivars For Aluminium Sensitivity In Nutrient Soluations, F O. Gallardo, S Benavides, R Demanet, F Borie Mar 2024

Screening Ryegrass Cultivars For Aluminium Sensitivity In Nutrient Soluations, F O. Gallardo, S Benavides, R Demanet, F Borie

IGC Proceedings (1977-2023)

The objective of this study was to evaluate Al and H+ tolerance of nine ryegrass (Lolium perenne and L. multiflorum) cultivars by growing plants in a mineral solution (pH 4.8 and 6.0 and 0-200 (M Al). Results showed that Yatsyn-1, with a relative root length of 91 was the cultivar least affected by acidity (H+), and Concord ( RRLpH = 58) was the cultivar with the highest H+ sensitivity. In connection with Al-tolerance, Yatsyn-1 and Concord, were the most tolerant cultivars with 88 and 87 RRLAl, respectively whereas Nui and Marathon, were the most sensitive ones, reaching only …

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Breeding For Persistence In Lotus Corniculatus, M Rebuffo, N Altier Mar 2024

Breeding For Persistence In Lotus Corniculatus, M Rebuffo, N Altier

IGC Proceedings (1977-2023)

The objectives of this study were to develop a more persistent germplasm of birdsfoot trefoil (Lotus corniculatus L.) and to evaluate its potential use in Uruguay. Two cycles of phenotypic recurrent selection were done under field conditions. Eight hundred and 1600 spaced plants were established for the first and second cycle of selection. Both nurseries were visually assessed for crown rot, relative growth, plant habit and foliar diseases. The final selection of the breeding population LE 65-56 includes thirty six plants selected from sixteen elite families. This selection was more persistent and productive than the check varieties in plot …

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Apomixis And The Reproductive Dynamics Of Eastern Gamagrass Tripsacum Dactyloides L., B Kindiger, C L. Dewald Mar 2024

Apomixis And The Reproductive Dynamics Of Eastern Gamagrass Tripsacum Dactyloides L., B Kindiger, C L. Dewald

IGC Proceedings (1977-2023)

Studies were conducted to determine the reproductive characteristics of Tripsacum, a perennial, native pasture species and to identify methods for breeding agronomically superior cultivars. Reproductive methods and types of individuals generated were evaluated with triploid and hexaploids possessing a novel method for transferring sexual germplasm into apomictic tetraploids and tetraploid germplasm into sexual diploids. Triploids and hexaploids are demonstrated to be useful materials for introgressing and transferring desirable alleles across ploidy levels and reproductive barriers.

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Cytogenetical Studies In Range Grasses Of Iran, M Sheidai, A Tavasoli, P Derakhshandeh Mar 2024

Cytogenetical Studies In Range Grasses Of Iran, M Sheidai, A Tavasoli, P Derakhshandeh

IGC Proceedings (1977-2023)

Cytogenetical and breeding studies of range grasses are in hand. Present article describes preliminary cytogenetical analysis of wheatgrass (Agropyron) and bromegrass (Bromus) taxa (Agropyron trichophorum n = 21, A. pectinoforome n = 21), two different populations of A. repens (n = 28) and Bromus stenostachyus (n = 14). The species varied with regard to chiasma number and distribution. The highest value occurred in A. repens (Mako population). Heterogenity test for the paired samples showed lack of heterogenity for chiasmata indicating homogenity of Agropyron taxa. However a test for ring and rod bivalents showed significant differences …

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Direct Selection Response For Stem Rust Resistance In Tall Fescue, R E. Barker, R E. Welty Mar 2024

Direct Selection Response For Stem Rust Resistance In Tall Fescue, R E. Barker, R E. Welty

IGC Proceedings (1977-2023)

Resistance to stem rust (caused by Puccinia graminis Pers.: Pers. subsp. graminicola Z. Urban.) would be beneficial in tall fescue (Festuca arundinacea Schreb.). Two cycles of polycross (PX) selection on progenies from thirty-four parent plants (14 forage-types and 20 turf-types) were compared to one cycle of open pollination (OP) followed by one cycle of PX selection using a 2-stage greenhouse screening process. Response from selection was determined from composite half-sib progenies from each cycle. Number of plants with resistant reaction based on pustule type increased from 5 to 54% in the PX forage-type population and from 6 to 50% …

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Assessment Of Grazing Procedures In The Evaluation Of Plant Breeding Material, D Real, I L. Gordon, J Hodgson Mar 2024

Assessment Of Grazing Procedures In The Evaluation Of Plant Breeding Material, D Real, I L. Gordon, J Hodgson

IGC Proceedings (1977-2023)

Four stocking densities (2, 3, 5 and 9 sheep/18 m2 for one hour) and two times of grazing (morning or evening) were imposed on a spaced plant nursery of nine red clover (Trifolium pratense L.) populations of varying growth habit, in order to optimize measurement of sheep grazing preference. Plant height, spread and leafiness were measured before and after each of three grazings. Sheep preference was viewed multivariately, using combined measurements of these plant characteristics. MANOVA revealed that the effect of stocking density was significant (P-0.05), but that of time of grazing was not. The plant, population and overall …

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Developing Well Adapted Early To Midseason Cultivars Of Trifoiloum Subterraneum Ssp. Brachycalycinum, C T. De Koning, P G.H. Nichols, R L. Tuckwell, N Schubert Mar 2024

Developing Well Adapted Early To Midseason Cultivars Of Trifoiloum Subterraneum Ssp. Brachycalycinum, C T. De Koning, P G.H. Nichols, R L. Tuckwell, N Schubert

IGC Proceedings (1977-2023)

Development and selection of early to midseason cultivars of subterranean clover (Trifolium subterraneum L.) ssp. brachycalycinum has mostly involved the use of early generation selection nursery swards (F2-progeny method). Four sites were sown in the mid-North region of South Australia. At the end of 1995, the top 20 lines from each site had burrs (seed pods) sampled at random. The burr will proceed into the final early generation selection phase (1 - 2 years). Dependent on the site, many lines have out-performed the standard checkplot cultivar, Clare. High hardseed levels have also been incorporated into 1989 crossbreds.

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