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Articles 43951 - 43980 of 294391

Full-Text Articles in Physical Sciences and Mathematics

Varietal Differences In Perennial Ryegrass For Fructan Metabolism And Their Relationship To Grazing Tolerance, B. Lasseur, J. Lothier, A. Morvan-Bertrand, M. O. Humphreys, M. P. Prud'homme Apr 2023

Varietal Differences In Perennial Ryegrass For Fructan Metabolism And Their Relationship To Grazing Tolerance, B. Lasseur, J. Lothier, A. Morvan-Bertrand, M. O. Humphreys, M. P. Prud'homme

IGC Proceedings (1977-2023)

Perennial ryegrass (Lolium perenne L.) is the most important grass in Europe; it often is defoliated. The link between fructan metabolism and defoliation tolerance has been studied in 2 Lolium perenne varieties, Aurora (high sugar perennial) and Perma (low-to-normal sugar perennial) (Turner et al., 2002).

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Variability In Quantity And Composition Of Water Soluble Carbohydrates Among Irish Accessions And European Varieties Of Perennial Ryegrass, S. Mcgrath, S. Barth, A. Frohlich, M. Francioso, S. A. Lamorte, T. R. Hodkinson Apr 2023

Variability In Quantity And Composition Of Water Soluble Carbohydrates Among Irish Accessions And European Varieties Of Perennial Ryegrass, S. Mcgrath, S. Barth, A. Frohlich, M. Francioso, S. A. Lamorte, T. R. Hodkinson

IGC Proceedings (1977-2023)

The objective of this study was to identify perennial ryegrass accessions displaying high fructose and glucose contents and an improved ratio between fructose and glucose fractions across different time points throughout the year. Fructose and glucose are the main constituents of the water soluble carbohydrate (WSC) fraction in perennial ryegrass. For animal nutrition the amount of WSC is crucial as it is the primary energy source available to metabolise the intake of plant protein. The ratio between fructose and glucose fractions is important since fructosan chains, which are an excellent energy source for ruminants, are built from fructose. Furthermore the …

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Breeding Of Cms-F1-Hybrids In Lolium Perenne With Improved Nitrogen Use Efficiency, W. Luesink, B. Ingwersen, L. Wolters, J. De Riek Apr 2023

Breeding Of Cms-F1-Hybrids In Lolium Perenne With Improved Nitrogen Use Efficiency, W. Luesink, B. Ingwersen, L. Wolters, J. De Riek

IGC Proceedings (1977-2023)

The environmental pollution by nitrogen losses from dairy farms can be reduced by improving the nitrogen use efficiency (NUE) of grass varieties. The main goal is to develop varieties with a better nitrogen utilisation. These low input varieties can produce acceptable yields at a low level of N-fertilisation. High input varieties express their high yield potential only at high N-supply. These varieties are less preferable, because N- losses increase at higher levels of nitrogen application. The breeding of CMS-F1-Hybrids can be a successful strategy for developing varieties with a higher NUE. In F1-Hybrid varieties higher heterosis effects can be achieved …

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New Alkyd Resins From Underutilized Indigenous Seed Oils: Synthesis And Characterization, Aliru O. Mustapha, Hakeem B. Ayoku, Halimah A. Amao Apr 2023

New Alkyd Resins From Underutilized Indigenous Seed Oils: Synthesis And Characterization, Aliru O. Mustapha, Hakeem B. Ayoku, Halimah A. Amao

Karbala International Journal of Modern Science

The underutilization of sesame (Sesamum indicum L.), sweet almond (Prunus amygdalus), and jatropha (Jatropha curcas) seeds indicates a significant resource waste. Nine different varieties of 25% (short), 40% (medium), and 60% (long) alkyd resins were produced from the cross-section of drying, semi-drying, and non-drying oils. A large amount of conversion occurred, with the extent of the reaction (Pav) decreasing as time progressed and the corresponding increase in alkyds' average degree of polymerization (Dp) showing synthesized alkyds. Surface drying from the set-to-dry and dry-through periods climaxed at 2 hours for all the alkyds. Except for alkali, synthesized alkyd resins demonstrated outstanding …

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Using Integral Projection Models To Explore Management Strategies For Silver Carp (Hypophthalmichthys Molitrix), Cameron Coles, Elizabeth Balas, James Peirce, Greg Sandland, Richard Erickson Apr 2023

Using Integral Projection Models To Explore Management Strategies For Silver Carp (Hypophthalmichthys Molitrix), Cameron Coles, Elizabeth Balas, James Peirce, Greg Sandland, Richard Erickson

Spora: A Journal of Biomathematics

Silver carp (Hypophthalmichthys molitrix) are planktivorous fish that were originally introduced to the United States for use in fish production ponds and have since escaped these enclosures and are invading the Mississippi River Basin. The silver carp invasion of the Illinois River has a myriad of negative effects on native ecosystems. In this paper, we introduce key dependencies that are likely important in the population dynamics of silver carp: length-dependent egg production and density-dependent growth. Using movement data between two adjacent pools of the Illinois River, we conduct numerical simulations to explore the theoretical effect of harvesting and …

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A Mathematical Model For Mosquito Population Dynamics, Christian Evans, Jemal Mohammed-Awel, Andreas Lazari Apr 2023

A Mathematical Model For Mosquito Population Dynamics, Christian Evans, Jemal Mohammed-Awel, Andreas Lazari

Georgia Journal of Science

In this study, a deterministic mathematical model for mosquito population dynamics is presented. The use of chemical insecticide to control population is incorporated into the model. It is assumed that there is insecticide sensitive (sensitive-type) and insecticide resistant (resistant-type) mosquitoes in the environment. Conditions for the existence and stability of four equilibria of the model have been established. Numerical simulations are carried out to confirm the analytical results and the implications, in terms of mosquito control in the environment, are discussed.

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A Survey Of European Regional Adaptation In Italian Ryegrass Varieties, T. J. Gilliland, A. J. P. Van Wijk Apr 2023

A Survey Of European Regional Adaptation In Italian Ryegrass Varieties, T. J. Gilliland, A. J. P. Van Wijk

IGC Proceedings (1977-2023)

Ryegrass is widely adapted to cool temperate eco-zones and breeders often submit individual varieties for testing in a number of EU countries. National testing programmes often combine data from several trial sites that may differ climatically, but not from sites in other member states, despite the possibility of high ecological similarity. Given increasing interest in animal value characters (soluble sugars, lipids, sward geometry), additional testing for these would be valuable but is prohibited by capped or declining funding. Data sharing between EU national authorities could be advantageous but is inhibited by the lack of statistically valid data on the sensitivity …

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Milk Production Potential Of Different Dairy Pasture Types In Southern Australia, J. Tharmaraj, D. F. Chapman, Z. N. Nie, A. P. Lane Apr 2023

Milk Production Potential Of Different Dairy Pasture Types In Southern Australia, J. Tharmaraj, D. F. Chapman, Z. N. Nie, A. P. Lane

IGC Proceedings (1977-2023)

The growth rate of traditional perennial ryegrass-based pastures commonly fails to meet herd feed requirements through winter and summer in non-irrigated dairy systems in southern Australia. Alternative pasture species can improve seasonal feed supply in this region (Tharmaraj & Chapman, 2005). However, the feeding value and milk production of these pastures must at least match perennial ryegrass if they are to be adopted successfully on dairy farms. This paper reports results of a comparison of the milk production potential of pasture types similar to those investigated by Tharmaraj & Chapman (2005) for their agronomic performance.

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Effect Of Strain Of Holstein-Friesian Cow And Feed System On Reproductive Performance In Seasonal-Calving Milk Production Systems Over Four Years, B. Horan, J. F. Mee, Myles Rath, P. O'Connor, P. Dillon Apr 2023

Effect Of Strain Of Holstein-Friesian Cow And Feed System On Reproductive Performance In Seasonal-Calving Milk Production Systems Over Four Years, B. Horan, J. F. Mee, Myles Rath, P. O'Connor, P. Dillon

IGC Proceedings (1977-2023)

In Ireland most dairy farms operate seasonal calving grass-based milk production systems. Feed demand and supply are matched by having calving highly concentrated in spring. This requires high pregnancy rates within a short time following the start of mating in late April or early May, but has become increasingly difficult to achieve due to declining fertility in Irish dairy herds (Mee, 2004). In New Zealand, cows of North American Holstein-Friesian origin have poorer fertility than New Zealand Holstein-Friesians on pasture-based seasonal calving systems (Harris & Kolver, 2001). The present study sought to determine the effect of strain of Holstein-Friesian (HF) …

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Phenotype X Herbage Allowance Interactions In Reproduction Of First Calf Heifers Grazing Semiarid Rangeland, J. W. Holloway, B. G. Warrington, M. K. Owens Apr 2023

Phenotype X Herbage Allowance Interactions In Reproduction Of First Calf Heifers Grazing Semiarid Rangeland, J. W. Holloway, B. G. Warrington, M. K. Owens

IGC Proceedings (1977-2023)

Cattle are differentially adapted to nutritional environments. The most sensitive measure of adaptation is reproduction of first-calf heifers. We studied the role of maturation rate and milk production on reproductive performance of first-calf heifers allowed different levels of herbage in semiarid rangeland.

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The Impact Of The Level Of Feed-On-Offer Available To Merino Ewes During Winter-Spring On The Wool Production Of Their Progeny As Adults, Chris Oldham, M. Ferguson, B. Paganoni, A. Thompson, G. Kearney, M. A. Van Burgel Apr 2023

The Impact Of The Level Of Feed-On-Offer Available To Merino Ewes During Winter-Spring On The Wool Production Of Their Progeny As Adults, Chris Oldham, M. Ferguson, B. Paganoni, A. Thompson, G. Kearney, M. A. Van Burgel

IGC Proceedings (1977-2023)

New opportunities for developing optimum ewe management systems, based on achieving liveweight and body condition score (CS) targets at critical stages of the reproductive cycle, have emerged from the acceptance that nutrition during pregnancy can have substantial impacts on the lifetime wool performance of the progeny (Kelly et al,. 1996). However, most studies of the impacts of nutrition on foetal growth and development tended to focus on late pregnancy and have also only considered extreme nutritional regimes often outside the boundaries of commercial reality. Hence, the Lifetime Wool team (Thompson & Oldham, 2004) conducted dose-response experiments to determine the …

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Effects Of Forage Chicory (Cichorium Intybus) On Farmed Deer Growth And Internal Parasitism, S. O. Hoskin, P. R. Wilson, W. E. Pomroy, T. N. Barry Apr 2023

Effects Of Forage Chicory (Cichorium Intybus) On Farmed Deer Growth And Internal Parasitism, S. O. Hoskin, P. R. Wilson, W. E. Pomroy, T. N. Barry

IGC Proceedings (1977-2023)

Internal parasitism (particularly lungworm - Dictyocaulus sp) significantly limits post-weaning growth of deer. Endoparasite control using anthelmintics may be unsustainable, due to the increasing risk of anthelmintic resistance and the risk or perception of chemical residues in animal products. Chicory has a high feeding value and contains sesquiterpene lactones and low levels of condensed tannins, both with anti-parasitic activity (Molan et al., 2003). Grazing chicory during autumn may reduce the requirement for anthelmintic treatment of young deer compared with grazing ryegrass-based pasture (Hoskin et al., 1999). The objective of this study was to investigate the effect of withholding …

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Science Club, Danielle Gibson, Krista Andersen Apr 2023

Science Club, Danielle Gibson, Krista Andersen

Honors Program: Expanded Learning Clubs

Honors After School program for elementary age children to engage with scientific principles. Students performed hands-on experiments to explore various STEM fields. Each weekly lesson consisted of a different concept to be learned or explored by early elementary aged students.

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Earthquake Resistant Buildings, Admin Stem For Success Apr 2023

Earthquake Resistant Buildings, Admin Stem For Success

STEM for Success Showcase

Students learn about earthquakes and engineering by building a structure that can survive an earthquake.

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Candy Heart Experiment, Admin Stem For Success Apr 2023

Candy Heart Experiment, Admin Stem For Success

STEM for Success Showcase

Students practice the scientific process by running an experiment to discover how well candy hearts dissolve in different liquids.

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Goonie Shooters Activity, Admin Stem For Success Apr 2023

Goonie Shooters Activity, Admin Stem For Success

STEM for Success Showcase

Students are asked to design a "Goon Shooter" to launch "goons" as far as possible.

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Comments On The: Response To Comments Butte Priority Soils Operable Unit (Bpsou) Clark Tailings Consolidated Waste Management Area Site Investigation Quality Assurance Project Plan (Qapp) (Dated February 28, 2023), Nikia Greene Apr 2023

Comments On The: Response To Comments Butte Priority Soils Operable Unit (Bpsou) Clark Tailings Consolidated Waste Management Area Site Investigation Quality Assurance Project Plan (Qapp) (Dated February 28, 2023), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Kinetic Analysis Of Glu115ala Cytosolic Human Malate Dehydrogenase Mutation Shows A Change In Activity On Non-Native Substrate Phenylpyruvate, Kailey Paar Apr 2023

Kinetic Analysis Of Glu115ala Cytosolic Human Malate Dehydrogenase Mutation Shows A Change In Activity On Non-Native Substrate Phenylpyruvate, Kailey Paar

Chemistry & Biochemistry Student Scholarship

The cytosolic human enzyme, malate dehydrogenase (MDH1), is believed to have a significant effect on the proliferation of cancerous cells. This enzyme oxidizes NADH to NAD+ as it converts oxaloacetate (OAA) to malate. This oxidation of NADH provides the needed NAD+ to cancer cells, which require NAD+ as they upregulate glycolysis in aerobic conditions. Targeting MDH1 can reveal new therapeutic treatments for cancer by preventing the conversion of OAA to malate and depleting NAD+ stores in cancer cells, which can be done by mutating residues in the enzyme and assessing the change in activity. Here we show the replacement of …

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Sleigh Race Project, Admin Stem For Success Apr 2023

Sleigh Race Project, Admin Stem For Success

STEM for Success Showcase

Students use their knowledge of physics and design to build both a sleigh and a slope for the sleigh to travel on.

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Lesson Plans In Astronomy, Ecology And Biology, Admin Stem For Success Apr 2023

Lesson Plans In Astronomy, Ecology And Biology, Admin Stem For Success

STEM for Success Showcase

This document contains various lesson plan ideas for concepts within the fields of biology, ecology, astronomy, and geology.

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From Point Estimates To Predictive Distributions In Machine Learning Models - A Statistical Importance Sampling Framework, Giuseppina Carannante Apr 2023

From Point Estimates To Predictive Distributions In Machine Learning Models - A Statistical Importance Sampling Framework, Giuseppina Carannante

Theses and Dissertations

In this thesis, we leverage powerful statistical frameworks for optimal sequential estimation and tracking in non-linear and non-Gaussian dynamical models, which enjoy proven (asymptotic) optimality properties. Initially, we build upon our previous work, which employed first-order Taylor series approximation to propagate the first two predictive moments, to derive Bayesian encoder-decoder networks. This work introduced the notion of dense, pixel-level uncertainty map that is crucial in fields, such as autonomous vehicles and medical segmentation. We then extended the Bayesian framework to an ensembling scheme based on ensemble Kalman Filtering (EnKF). While EnKF represents the predictive distribution with an ensemble of draws, …

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2023 Final Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Organic Pollutant Surface Water Sampling Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc. Apr 2023

2023 Final Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Organic Pollutant Surface Water Sampling Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Testing Pedagogical Approaches To Online Lecture: Effects Of Background Music And Interactive Video Series On Student Retention Of Prior Conception-Correcting Information On Climate Change, Roya Franseth Apr 2023

Testing Pedagogical Approaches To Online Lecture: Effects Of Background Music And Interactive Video Series On Student Retention Of Prior Conception-Correcting Information On Climate Change, Roya Franseth

Honors Projects

Climate change is a pervasive element in our modern lives, yet many harbor ideas about climate change and associated climate mechanisms that are misinformed or incorrect. Ideas like these – prior conceptions (ideas that people carry with them into learning experiences about a subject) – are studied in varying degrees across fields. The geosciences do not have a particularly robust collection of research on the subject of geoscience-specific prior conceptions. At the same time, due to the COVID-19 pandemic, alternatives to in-person lecture such as online lecture have become normalized. The original aim of this paper was to determine if …

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Approval Letter For The Butte Priority Soils Operable Unit, Final 2022 Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp) Corrective Action Report (February 22, 2023), Nikia Greene Apr 2023

Approval Letter For The Butte Priority Soils Operable Unit, Final 2022 Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp) Corrective Action Report (February 22, 2023), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Final Butte Priority Soils Operable Unit, 2021 Insufficiently Reclaimed Sites Sampling Clark Mill Tailings (Bres No. 154) Site Evaluation Summary Report, Dated (February 22, 2023), Nikia Greene Apr 2023

Final Butte Priority Soils Operable Unit, 2021 Insufficiently Reclaimed Sites Sampling Clark Mill Tailings (Bres No. 154) Site Evaluation Summary Report, Dated (February 22, 2023), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Final Butte Priority Soils Operable Unit, 2021 Insufficiently Reclaimed Sites Sampling Colorado Dump (Bres No. 104) Site Evaluation Summary Report (February 21, 2023), Nikia Greene Apr 2023

Final Butte Priority Soils Operable Unit, 2021 Insufficiently Reclaimed Sites Sampling Colorado Dump (Bres No. 104) Site Evaluation Summary Report (February 21, 2023), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Approval Letter For: Final Butte Priority Soils Operable Unit, 2021 Unreclaimed Sites Sampling Ur-03 Site Evaluation Summary Report (February 7, 2023), Nikia Greene Apr 2023

Approval Letter For: Final Butte Priority Soils Operable Unit, 2021 Unreclaimed Sites Sampling Ur-03 Site Evaluation Summary Report (February 7, 2023), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Magnetic Slime, Admin Stem For Success Apr 2023

Magnetic Slime, Admin Stem For Success

STEM for Success Showcase

Students learn chemistry and physics by making magnetic slime.

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Invisible Ink, Admin Stem For Success Apr 2023

Invisible Ink, Admin Stem For Success

STEM for Success Showcase

Students create invisible ink to hide and reveal a message using chemistry.

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Skew Relative Hadamard Difference Set Groups, Andrew Haviland Apr 2023

Skew Relative Hadamard Difference Set Groups, Andrew Haviland

Theses and Dissertations

We study finite groups $G$ having a nontrivial subgroup $H$ and $D \subset G \setminus H$ such that (i) the multiset $\{ xy^{-1}:x,y \in D\}$ has every element that is not in $H$ occur the same number of times (such a $D$ is called a {\it relative difference set}); (ii) $G=D\cup D^{(-1)} \cup H$; (iii) $D \cap D^{(-1)} =\emptyset$. We show that $|H|=2$, that $H$ has to be normal, and that $G$ is a group with a single involution. We also show that $G$ cannot be abelian. We give examples of such groups, including certain dicyclic groups, by using results …

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