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Investigation Of Yy Production Methods For Invasive Channel Catfish Ictalurus Punctatus Population Management, Andrew M. Wisniewski Aug 2026

Investigation Of Yy Production Methods For Invasive Channel Catfish Ictalurus Punctatus Population Management, Andrew M. Wisniewski

All Graduate Theses and Dissertations, Fall 2023 to Present

Aquatic invasive species are one of the leading causes of native fish declines in the Southwestern United States. Channel Catfish Ictalurus punctatus were introduced into the Colorado River Basin, including the San Juan River, New Mexico, Colorado, and Utah for fishery enhancement during the 20th century. This introduction has contributed to the decline of native species and despite intensive mechanical removal efforts, the Channel Catfish population has persisted in the San Juan River. The Trojan Sex Chromosome approach is a promising eradication strategy that proposes the production and release of Trojan sex chromosome carriers (YY) to skew a targeted population’s …


Drought And Diet Breadth: Does Insect Specialization Influence Herbivory When Plants Are Under Stress?, Jakob Palmer Aug 2026

Drought And Diet Breadth: Does Insect Specialization Influence Herbivory When Plants Are Under Stress?, Jakob Palmer

All Graduate Theses and Dissertations, Fall 2023 to Present

Climate change will alter precipitation worldwide, causing more frequent and severe drought events worldwide. Drought affects many ecological processes, including plant-herbivore interactions, which are critical to biodiversity and ecosystem health. A variety of plant characteristics can influence herbivory – such as how hairy, nutritious, or toxic a leaf is – and drought has been shown to alter many of these traits. Unique characteristics of herbivore species are also important: herbivores can either feed on a variety of plants (generalists) or a group of closely related plants (specialists). Specialists can cope with traits of the plants they eat, while generalists are …


A Data-Driven Nutrient Density Scoring Framework For Beef Using Principal Component Analysis, Teja Vuppala Aug 2026

A Data-Driven Nutrient Density Scoring Framework For Beef Using Principal Component Analysis, Teja Vuppala

All Graduate Theses and Dissertations, Fall 2023 to Present

Beef is one of the most nutrient-rich foods in the human diet, providing high-quality protein, iron, omega-3 fatty acids, B vitamins, and a wide range of other compounds important to health. However, current nutrition scoring systems used on food labels were designed to compare different foods to one another — for example, beef versus broccoli — and do not work well for judging the nutritional quality of different beef samples relative to each other. A grass-fed steak and a conventionally-finished steak can carry nearly identical Nutrition Facts panels while differing substantially in their content of omega-3 fatty acids, vitamins, and …


Integrating Hydrology And Human Water Footprints: A Case Study Of The Great Salt Lake Basin, Rachel Lynne Seeley Aug 2026

Integrating Hydrology And Human Water Footprints: A Case Study Of The Great Salt Lake Basin, Rachel Lynne Seeley

All Graduate Theses and Dissertations, Fall 2023 to Present

Global demand for water is outrunning supply, and how we account for water is part of the problem. Many water management frameworks are based solely on how much physical water moves through rivers, aquifers, and other water bodies, missing the water that is embedded in food and other products a region produces and exports. This study developed a new, generalizable water accounting framework that incorporates this “hidden water,” known as virtual water, into water management and applied the framework in the Great Salt Lake Basin.

The Great Salt Lake is shrinking, and an often-overlooked driver of the lake’s decline is …


Viability Assessment Of Bovine Embryos: A Public Dataset And Deep Learning Baselines, Erfan Khayyati Aug 2026

Viability Assessment Of Bovine Embryos: A Public Dataset And Deep Learning Baselines, Erfan Khayyati

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the success rates of cattle breeding is essential for sustainable agriculture, global food security, and high-quality livestock production. Currently, determining whether a lab-grown bovine embryo is healthy enough for a successful pregnancy requires highly trained experts to manually evaluate days of continuous time-lapse video footage. This process is not only incredibly time-consuming but also highly subjective; human reviewers often suffer from visual fatigue when tracking subtle, microscopic cellular changes over a seven-day period, leading to significant disagreement among even top experts on an embryo’s true potential. Furthermore, assessing bovine embryos is notoriously difficult due to their dark, lipid-dense cellular …


Why Technical Readiness Is Not Enough: Institutional Barriers To Full Harvest Strategy Adoption In The International Pacific Halibut Commission, Evelyn Roozee, Owen Temby, Gordon M. Hickey Aug 2026

Why Technical Readiness Is Not Enough: Institutional Barriers To Full Harvest Strategy Adoption In The International Pacific Halibut Commission, Evelyn Roozee, Owen Temby, Gordon M. Hickey

School of Earth, Environmental, & Marine Sciences Faculty Publications

Harvest strategies are increasingly promoted as a mechanism to reduce political discretion and align fisheries management with pre-agreed scientific objectives. While substantial progress has been made in tuna regional fisheries management organizations (RFMOs), non-tuna RFMOs have lagged behind. Existing research has focused primarily on technical modeling challenges, with comparatively limited attention to the governance dynamics shaping adoption. Using the International Pacific Halibut Commission (IPHC) as an instrumental case study, we examine the progress and delays in the development of a harvest strategy policy (HSP) through semi-structured interviews and participant observation. We find that the IPHC successfully addressed commonly cited barriers, …


Greenhouse Gas Flux Response In Biochar- And Compost-Amended Lawn Soils Under Simulated Water Saturation Conditions, Angel Salinas, Chu-Lin Cheng, Engil Pereira, Rafael M. Almeida, James Jihoon Kang Aug 2026

Greenhouse Gas Flux Response In Biochar- And Compost-Amended Lawn Soils Under Simulated Water Saturation Conditions, Angel Salinas, Chu-Lin Cheng, Engil Pereira, Rafael M. Almeida, James Jihoon Kang

School of Earth, Environmental, & Marine Sciences Faculty Publications

Understanding greenhouse gas emission dynamics in lawn soils is important for improving climate change mitigation strategies in urban and suburban landscapes. In this greenhouse mesocosm study, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes were measured from 12 turfgrass soil columns arranged in an unreplicated, completely randomized 4 × 3 factorial design. Four amendment treatments (biochar, compost, bio-com [1:1 volume ratio of biochar and compost], and unamended control) were combined with three water-table conditions (full saturation, half saturation, and unsaturated), with a single column representing each treatment combination. Columns were irrigated at 1 cm day−1 for 24 days, …


A Finite Element Model To Analyze Crack-Tip Fields In A Transversely Isotropic Strain-Limiting Elastic Solid, Saugata Ghosh, Dambaru Bhatta, S. M. Mallikarjunaiah Aug 2026

A Finite Element Model To Analyze Crack-Tip Fields In A Transversely Isotropic Strain-Limiting Elastic Solid, Saugata Ghosh, Dambaru Bhatta, S. M. Mallikarjunaiah

School of Mathematical & Statistical Sciences Faculty Publications

This paper presents a finite element model for the analysis of crack-tip fields in a transversely isotropic strain-limiting elastic body. A nonlinear constitutive relationship between stress and linearized strain characterizes the material response. This algebraically nonlinear relationship is critical as it mitigates the physically inconsistent strain singularities that arise at crack tips. These strain-limiting relationships ensure that strains remain bounded near the crack tip, representing a significant advancement in the formulation of boundary value problems (BVPs) within the context of first-order approximate constitutive models. For a transversely isotropic elastic material containing a crack, the equilibrium equation, derived from the balance …


Predicting Student Belonging In Computing Education: A Multimodal Machine Learning Approach Using Eeg And Survey Data, Hannah Moshtaghi Aug 2026

Predicting Student Belonging In Computing Education: A Multimodal Machine Learning Approach Using Eeg And Survey Data, Hannah Moshtaghi

Master's Theses

Measuring students’ sense of belonging, characterized by feelings of acceptance, inclusion, and encouragement from teachers, remains a significant challenge in computing education. Prior research has associated this multidimensional construct with positive academic outcomes and has identified instructors’ growth- and fixed-mindset messaging as a potential influence. However, belonging is a complex and deeply personal experience that is difficult to capture through direct observation alone. Current measurement methods rely on self-report surveys, which may not capture every aspect of an experience that can also involve emotional and cognitive responses.

This thesis investigates whether combining EEG data recorded during a belonging questionnaire with …


Piracy, Terrorism, And The Law: Differential Equations In Hostage Situations, Gabriel Hallevy Jul 2026

Piracy, Terrorism, And The Law: Differential Equations In Hostage Situations, Gabriel Hallevy

Journal of Humanistic Mathematics

Pirates have taken the crew of an American ship hostage. They promise to release the hostages only if another pirate who is held in an American prison for commission of piracy crimes against American citizens, is released. Should the U.S. government enter into negotiations with them? Should they send armed forces and risk the hostages? Should they release the prisoner immediately and unconditionally? The article models and analyzes possible policies regarding sensitive situations involving hostages and other related risks using differential equations. The solutions are surprisingly simple, but not necessarily intuitive. Our analysis aims to demonstrate how powerful mathematics is …


Technological Behaviour Of Pellets Containing Dried Green Crop, Christian Furll Jul 2026

Technological Behaviour Of Pellets Containing Dried Green Crop, Christian Furll

IGC Proceedings (1977-2023)

Pelleted dried green crop presents essential advantages compared to chaff and meal as processing forms. Normally, the solidity of the pellets does not exceed the values required by animal feeding. Abrasion resulting from turnover processes is at present too high, particularly for the discharge of bins. Belt conveyors, vibrating conveyors, and bucket elevators are suitable to convey pellets. Storage of pellets over long periods has to be done by respecting prescribed climate conditions. Zones with excessive portion of abraded par­ticles in the storing pile are a preferred cause for self-heating. Slit-type dosing units as well as dosing units equipped with …


Results Of Comparative Investigations Into The Chevving And Ruminating Activities Of The Dairy Cow Fed Dried Forage From Grass And Leguminous Crops, B Piatkowski, S Nagel Jul 2026

Results Of Comparative Investigations Into The Chevving And Ruminating Activities Of The Dairy Cow Fed Dried Forage From Grass And Leguminous Crops, B Piatkowski, S Nagel

IGC Proceedings (1977-2023)

The chewing and ruminating activities were studied of dairy cows fed grass, alfalfa, and straw of different physical forms. An electronic­ally controlled measuring device was applied. When feeding 8 kg of grass hay (32 % crude fibre in dry matter), the ruminating time was 5: 24 and 1 :49 hours (20,712 and 6,982 ruminat­ing movements) for chopped and ground + pelleted forages, respectively. It declined from 1 : 49 to 0: 0 l hours (from 6,929 to 70 move­ments) when hot-air dried alfalfa (23 % crude fibre) was fed in chopped and ground + pelleted forms, respectively. The ruminating time …


Feed Efficiency In Dairy Cows Of Roughages Preserved And Treated In Different Ways, M Zausch, E Boldt Jul 2026

Feed Efficiency In Dairy Cows Of Roughages Preserved And Treated In Different Ways, M Zausch, E Boldt

IGC Proceedings (1977-2023)

Trials were conducted with dairy cows to investigate the feed efficiency of grass-clover mixture (wilted silage, silage made of fresh material with addition of foDTiic acid, artifi­cially dried forage, pellets with varying portions of straw). The results obtained allow to draw the following conclusions:

As regards dry matter intake, digestibility, and feed efficiency, grass-dover for wilted silage should be wilted to give a OM content not exceeding 40 %.

Pelleting artificially dried grass-clover mix­ture and its use in mixed rations together with other separately pelleted components should be avoided.

The best feed efficiency is reached when dried grass-clover is converted …


The Influence Of Dried And Ensiled Grass On Rumen Fermen­Tation, J Voigt, B Piatkowski Jul 2026

The Influence Of Dried And Ensiled Grass On Rumen Fermen­Tation, J Voigt, B Piatkowski

IGC Proceedings (1977-2023)

Rumen-fistulated cows were used to study the influence of the forage preservation technique on rumen fermentation and holdup time of the feed in the rumen. Cocksfoot (Dactylis glomerata) preserved as wilted silage or dried green crop was fed in the following variants: wilted silage alone; wilted silage + sugar beet + protein supplement; dried green crop alone; dried green crop + sugar beet + protein supplement. As compared with dried green crop, the shares of true protein and sugar in wilted silage were reduced from 9.8 • to 6.4 '.'I􀉧 and from 7.7 to 1.8 %in DM, respectively. In comparison …


Changes In Feeding Value Of Preserved Grass And Legumes By The Action Of High Temperatures, R Prym, F Weissbach Jul 2026

Changes In Feeding Value Of Preserved Grass And Legumes By The Action Of High Temperatures, R Prym, F Weissbach

IGC Proceedings (1977-2023)

High temperatures acting on grass and legumes during preservation and storage, cause nutrient digestibility to deteriorate. Protein digestibility is likely to be most strongly affected. Digest­ibility measurements were performed on sheep to estimate the extent of heat damage suffered by dried green forage and silages. Various laboratory methods were applied for record­ing. such damage. The detennination of the acid-detergent insoluble crude protein portion proved a very suitable approach.


Growth And Nitrogen Retention Of Lambs Fed Alfalfa Dehy­Drated At Different Temperatures, H K. Goering Jul 2026

Growth And Nitrogen Retention Of Lambs Fed Alfalfa Dehy­Drated At Different Temperatures, H K. Goering

IGC Proceedings (1977-2023)

Alfalfa was dried at four temperatures ranging from 60 to 180 °C in two experiments to evaluate the effect on composition, diet di­gestibility, and growth by lambs. In Experi­ment I, the alfalfa was supplemented with 0.6 % salt and pelleted. In Experiment 2, alfalfa was supplemented with 24.4 % starch, 18.5% straw, 6% cane molasses, 0.5% sodium phosphate, and 0.6 % salt so that total nitrogen intake was not in excess of the protein require­ment for growth of the lambs. Cell wall, acid­detergent fiber, lignin, acid-detergent insoluble nitrogen, and pepsin insoluble nitrogen in­creased in the alfalfa dried at 180 °C. …


Non-Mechanical Field Losses In Wilting Grasses As Influenced By Different Factors, G Rucker, O Knabe Jul 2026

Non-Mechanical Field Losses In Wilting Grasses As Influenced By Different Factors, G Rucker, O Knabe

IGC Proceedings (1977-2023)

When wilting grasses, non-mechanical field losses of different extent may occur. The main factors influencing the extent of losses were: water content at cutting time, drying rate, temperature, amount of rain, swath den­sity, and content of water-soluble carbohy­drates in the crop.


The Effect Of Mechanical, Thermal And Chemical Treatment On The Loss Of Water From Cut Leaves Of Grasses, Colin Edward Harris Jul 2026

The Effect Of Mechanical, Thermal And Chemical Treatment On The Loss Of Water From Cut Leaves Of Grasses, Colin Edward Harris

IGC Proceedings (1977-2023)

Laboratory experiments have demonstrated that cut grass -leaves have a high resistance to water loss, probably largely due to the imper­meability of the surface cuticle to water vapour. This resistance can be reduced and drying rate increased by thermal and mechanical treatment, and by exposure to the vapour of boiling petroleum ether. The effectiveness of formic acid and tri-n-butyl phosphate suggests the possibility of using chemicals to increase the drying rate of grass crops cut for hay and dried in the field.


Measures For Increasing The Efficiency Of Hot-Air Drying Of Forage, Siegfried Prufer, Gerd Neubert Jul 2026

Measures For Increasing The Efficiency Of Hot-Air Drying Of Forage, Siegfried Prufer, Gerd Neubert

IGC Proceedings (1977-2023)

In the GDR, the drying of wilted green forage as well as of whole plants of cereals and grain maize considerably improves the effi­ciency of hot-air drying as a whole. The proc­essing of wilted crop and the inclusion of whole-plant drying in the drying pattern cause the throughput to increase by 30 to 50% and fuel consurnption per ton of dried crop to de­crease by up to 50 %, in comparison with drying of fresh green forage containing 15 to 18 % dry matter. Hot-air drying is particularly suitable for feed production along industrial lines. -Being but little dependent on …


Gdr Standard Plant For Producing Feed Pellets On Straw Basis, Gerheard Schmidt Jul 2026

Gdr Standard Plant For Producing Feed Pellets On Straw Basis, Gerheard Schmidt

IGC Proceedings (1977-2023)

Following the international trend, livestock production units are growing in size. Straw, a major feed reserve, must be effectively utilized to meet the growing roughage requirements, especially of ruminants. Therefore, in the GDR a standard feed pelleting plant (type GF A) was developed and put to commercial production. The various machines and equipment em­ployed in the different stages of the GFA pellet­ing technology are explained in detail. The use of that standard feed pelleting plant shows the advantages of processing straw for semi-finished and finished feeds.


The Efficiency Of Producing And Feeding Complete-Ration Feed Briquets Containing Forage Chop, G V. Blagoveshcheski, V M. Sokolov Jul 2026

The Efficiency Of Producing And Feeding Complete-Ration Feed Briquets Containing Forage Chop, G V. Blagoveshcheski, V M. Sokolov

IGC Proceedings (1977-2023)

Production of forage chop from a clover­timothy mixture is efficient when harvesting the forage between the shooting of clover (35 to 40 cm stand height) and mid-flowering. For high-temperature drying, each vegetative stage of the plants requires a clearly defined regime. When establishing formulas for com­plete-ration feed briquets containing clover­timoihy chop harvested before clover budding, the protein/carbohydrate ratio must be bal­anced by supplementing the ration with 30 p.c. barley meal and 29 p.c. straw; when the mix­ture was harvested during budding, phos­phorus supplementation (one p.c. monocal­cium phosphate) is necessary, whilst the mix­ture harvested during flowering has to be supplemented with …


The Production Of Dry Feeds From Straw And Green Forage In The Gdr, Fritz Berg Jul 2026

The Production Of Dry Feeds From Straw And Green Forage In The Gdr, Fritz Berg

IGC Proceedings (1977-2023)

In the GDR, at present about 9% of the feed energy requirement of cattle is covered by dry feeds, above all mechanically processed and chemically treated straw as well as dried green forages. This share is expected to rise to 15 % in forthcoming years. On the basis of technological fundamentals devised by animal nutritionists, corresponding production processes are being developed and perfected. They allow to convert the feedstuffs into a physical and chemical form favourable to high intake; in addition, the feeding value of high-fibre feedstuffs is improved. In this way, the feedstuffs are fed in favourable com­bination as …


Evaluation And Determination Off Actors Defining The Length Of Thin-Stalked Green Forage Chop, Peter Szendro Jul 2026

Evaluation And Determination Off Actors Defining The Length Of Thin-Stalked Green Forage Chop, Peter Szendro

IGC Proceedings (1977-2023)

A more exact analysis of the length distribution of chopped material from thin-stalked green forage crops provides more information for the further processing of this material and for comparing the quality of work of the different technologies. Material cut into longer and less homoge­neous chop with heavier destruction of the green plant particles shows properties more suitable for further processing than chop harvested with a self-propelled precision-chop forage harvester. In consideration of the special importance of the questions discussed it seems advisable to continue the experiments and to perform them under production conditions as well; the results thus obtained will …


Organization Of Wilted Silage Production Along Industrial Lines In The Selbelang Inter-Farm Cooperative Crop Produc­Tion Division, Hunter Watzke, Karl Bachmann Jul 2026

Organization Of Wilted Silage Production Along Industrial Lines In The Selbelang Inter-Farm Cooperative Crop Produc­Tion Division, Hunter Watzke, Karl Bachmann

IGC Proceedings (1977-2023)

The production of high-quality wilted silages on the basis of highly efficient machines and facilities for harvesting and preservation in the Selbelang inter-farm cooperative crop pro­duction division (KAP) is determined by the use of industrial methods of production. Ob­servance of optimum spans for harvesting forage to be used for the production of wilted silage, and the full utilization of machinery and facilities at rising levels of labour pro­ductivity and declining cost are achieved by way of complex and shift employment of machines, facilities, and workers. The size of machine complexes and their performance are dependent on the shape, equipment and …


Possibilities Of Ensiling Meadow Grass With Different Water Content, Roman Moraczewski, Helena Jurkiewicz Jul 2026

Possibilities Of Ensiling Meadow Grass With Different Water Content, Roman Moraczewski, Helena Jurkiewicz

IGC Proceedings (1977-2023)

The paper involves results of investigations into the influence of various methods of grass preservation, different cutting times, and dif­Jerent water contents on the nutrient and min­eral levels in the silage. These results show good possibilities of preserving meadow grass by ensiling. Silage fodder has higher contents of crude protein, crude fibre, crude fat, and ash constituents than are found in hay dried under optimum conditions.


Material And Processing Characteristics Of Grasses And Grass Silages, Manfred Muller, Georg Otto Jul 2026

Material And Processing Characteristics Of Grasses And Grass Silages, Manfred Muller, Georg Otto

IGC Proceedings (1977-2023)

Material and processing characteristics are essential initial values for planning of proce­dures in industrialized crop production. From the technological stages and process sequences from grass mowing to removing the silage, the following key operations can be derived: chop­ping,. compressing, storing, and removing. For adequate planning of procedures it is necessary to determine the quantitative relations between the essential factors: chopper throughput, pro­portion of short chop, crude fibre content, and relative final density. A relation suitable for practical application and providing sufficient accuracy is established for estimating the mean dry matter content of a trailer load. If high­quality silage is to …


Comparison Of Three Techniques Of Forage Conservation, Tereza Kotapska, Tadeusz Olszewski Jul 2026

Comparison Of Three Techniques Of Forage Conservation, Tereza Kotapska, Tadeusz Olszewski

IGC Proceedings (1977-2023)

At the Instytut Mechanizacji i Elektryfikacji Rolnictwa technological trials have been per­formed on green forage conservation under plastic sheeting using round formers from the Italian manufacturers Frigieri, a silage press from the French firm Kuhn, and portable seg­ments of Polish production for the erection clamp silos. The trials covered the operating quality of the equipment and the evaluation of silage quality. During the trials, the performance of the equipment on erecting the silos and specific labour expenditure were established. In addi­tion, an economic rating was made of the ensiling process and of the general suitability of the above methods for …


Losses And Stability Of Silage In Dependence On The Degree Of Air Influence, G Weise, H Rettig, G Suckow Jul 2026

Losses And Stability Of Silage In Dependence On The Degree Of Air Influence, G Weise, H Rettig, G Suckow

IGC Proceedings (1977-2023)

On the basis of model concepts of physical gas exchange, a method has been developed for studying the complex relations existing be­tween the parameters indicating ensilability and the specific local conditions for silage making (degree of anaerobiosis). Conclusions are drawn as to quantitative relations between the depth of the peripheral layers of a silage stock that are endangered by air, the initial density of the silage material, and the sealing of the silage top during the filling and storage periods. Therefrom, certain thresh­olds can be derived for minimum filling height per day as depending on the initial density of the …


Factors Influencing The Formation Of Effluent In Forage Ensiling, G Peters, F Weissbach Jul 2026

Factors Influencing The Formation Of Effluent In Forage Ensiling, G Peters, F Weissbach

IGC Proceedings (1977-2023)

The amount of effluent formed in ensiling forage crops depends, above all, on the dry matter content of the initial material, on the pressure exerted on the feed stock, and on the kind of crop ensiled. Expected values of effluent a­mount were derived from model experiments and calculations. Adequate wilting of suitable forage crops will allow to reduce or prevent effluent formation. The degree of wilting re­quired depends on the height of the feed stock and on the kind of silo used. The limit of 30 % DM in initial material, so far generally accepted for effluent formation, only applies …


Wilted Silage Production For The Supply Of Large Cattle Populations, Wilhelm Schwandt Jul 2026

Wilted Silage Production For The Supply Of Large Cattle Populations, Wilhelm Schwandt

IGC Proceedings (1977-2023)

For supplying large cattle populations with high-quality roughage it is necessary to make available big forage batches of good and large­ly uniform quality. From 4,675 hectares of seed­ed grassland, the ZBE Pflanzenproduktion Ferdinandshof(Ferdinandshofinter-farmestab­lishment for crop production) every year pro­duce in good quality more than 80,000 tons of wilted silage. The material and technical basis of this forage production along industrial lines consists of powerful machine systems that are operated in multi-machine complexes, the oper­ators doing shift work.