Digital Commons Network^™

Assessment Of The Nitrogen Nutrition Index (Nni) By The Nitrogen Concentration Of The Upper Part Of The Sward, B. Deprez, R. Lambert, A. Peeters

IGC Proceedings (1977-2023)

The Nitrogen Nutrition Index (NNI) is based on the concept of a critical nitrogen concentration, defined as the minimum N concentration in the aerial biomass necessary to obtain maximum yield. Values of N_crit are high at the start of the growing period and decline during growth, in relation to dry matter accumulation (t DM/ha) according to the equation of Lemaire & Salette (1984): N_crit(%) = 4.8(DM)^-0.32. The NNI is calculated as the ratio of the actual N concentration of the sward to the N concentration required at a similar biomass to sustain non-limiting growth and biomass …

Modelling The Effect Of Breakeven Date In Spring Rotation Planner On Production And Profit Of A Pasture-Based Dairy System, P. C. Beukes, B. S. Thorrold, M. E. Wastney, C. C. Palliser, G. Levy, X. Chardon

IGC Proceedings (1977-2023)

The breakeven date is the expected date when pasture supply exceeds cow demand. This date is used to plan the rotation rates, slow during the winter, when pasture growth is low and cows are dry, to a fast rotation in spring, when growth is accelerating and most cows lactating. This date is influenced by regional climate, mainly rainfall and soil temperature, which affects timing and rate of growth acceleration. The objective of this modeling exercise was to explore the effect of the breakeven date on milksolids (MS), grass silage, farm cover and economic farm surplus (EFS) over different climate years …

Development Of A Model Simulating The Impact Of Management Strategies On Production From Beef Cattle Farming Systems Based On Permanent Pasture, M. Jouven, R. Baumont

IGC Proceedings (1977-2023)

Grazing systems in Europe increasingly have to meet environmental objectives, which influence management strategies. A deterministic model describing farming system dynamics is being developed in order to elucidate interactions between nature-friendly management practices, as for example late (after flowering) hay harvest or moderate stocking rate, and agricultural output.

On-Farm Information: A Valuable Tool For The Sustainable Management Of Mountain Pastures In Protected Natural Areas, N. Mandaluniz, A. Bernués, A. Igarzabal, I. J. L. Riedel, R. Ruiz, A. Sanz, I. Casasús, L. M. Oregui

IGC Proceedings (1977-2023)

Mountain pastures have traditionally been maintained by livestock. The analysis of data concerning farms' characteristics, productive-reproductive management and land use of commercial farms can constitute a real approach to study these systems and the changes that are occurring. This information is necessary to develop new utilisation guidelines, making compatible livestock production and conservation of natural resources. This paper describes a methodological framework to study the issues described above through some examples taken out from a wider research project (Mandaluniz et al., 2003).

The Impact Of Concentrate Price On The Utilization Of Grazed And Conserved Grass, P. Crosson, P. O'Kiely, F. P. O'Mara, M. J. Drennan, M. Wallace

IGC Proceedings (1977-2023)

A linear programming model was designed and constructed to facilitate the identification of optimal beef production systems under varying technical and policy scenarios. The model operates at a systems level and most activities that could occur in Irish spring-calving, suckler beef production systems are included. In this paper, the components of the model are described together with a simple application of the model involving changing concentrate prices.

Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, Luc Delaby, J. L. Peyraud, P. Faverdin

IGC Proceedings (1977-2023)

The feeding of dairy cows at pasture presents many technical, economic and environmental advantages, while benefiting from a very favourable image. However, the management of grazed land is a complex game of strategy in which the farmer applies decisions in order to manage two unstable and uncertain fluxes of change: growth of grass and intake of the herd. Many tools (platemeter, etc.) and overall methods (local stocking rate references, farm cover, etc.) have been developed as aids to grazing management. Nevertheless, few decision-support systems are currently available that make it possible to anticipate and assess the consequences of a given …

Enhancing Grasslands Education With Decision Support Tools, Helen G. Daily, J. M. Scott, J. M. Reid

IGC Proceedings (1977-2023)

We have successfully used Decision Support Tools (DST) relevant to the management of grazing enterprises to enhance problem solving skills of undergraduates in Australia. Tools such as GrassGro^tm (Moore et al., 1997) and GrazFeed^tm (Freer et al., 1997) are accessed from a central server by authorised users at many widely dispersed Universities across Australia using remote access to thin-client technology via an Internet portal. This has been supplemented with training for lecturers. Experience in developing appropriate teaching and learning materials and the reliable delivery of simulation software to many clients has enhanced learning outcomes at tertiary …

Canasta - Crop Niche Selection For Tropical Agriculture, A Spatial Decision Support System, R. O'Brien, M. Peters, R. Corner, S. Cook

IGC Proceedings (1977-2023)

Farmers in the developing world frequently find themselves in uncertain and risky environments, often having to make decisions based on very little information. Risks for smallholder farmers are often critical because of their poverty. In addition, in the tropics and subtropics, the natural environment is spatially and temporally variable and often harsh, thereby increasing the uncertainty faced by these farmers. This research aims to improve forage adoption decisions in the developing world, thereby increasing sustainable intensification and ultimately contributing to increased sustainable world food production and the alleviation of under-nutrition.

Artturi Assists Finnish Advisers And Farmers To Succeed In Grass-Based Dairy Production, Marketta Rinne, Pekka Huhtanen, Kaisa Kuoppala, H. Nikander, J. Nousiainen, M. Hellämäki, L. Nyholm, J. Helminen, K. Lampinen, M. Maisi, M. Korhonen

IGC Proceedings (1977-2023)

Artturi is a collective name for a wide range of services. It is a common tool for different bodies who share an interest in strengthening grass-based dairy production in Finland: research, advisory service and industries. The Service is named after A. I. (Artturi Ilmari) Virtanen, the Finnish scientist who was awarded the Nobel prize in 1945, partly based on his work in developing the ensiling process of grass. The Artturi web site is available in Internet at: http://www.agronet.fi/artturi. Access to Artturi Services is free and no registration is required. The language used is Finnish. During summer 2003, 15,000 visits were …

A Decision Support System For Monitoring Livestock Diet Quality And Performance: Verification Study On Cattle, Adami Tulu, Ethiopia, A. A. Jama, G. Tolleson, J. W. Stuth, Abule Ebro, K. Zander, Robert J. Kaitho

IGC Proceedings (1977-2023)

Fecal profiling technology based on near infrared spectroscopy (NIRS) has been widely used in the U.S. to predict the diet quality and performance of free-ranging animals (e.g. Leite & Stuth 1995, Lyons & Stuth 1992, Lyons et al., 1993, Stuth et al., 1999, Tolleson et al., 2001). This technology is linked with the Nutritional Balance Analyzer (NUTBAL-PRO) model to form the core of a nutritional advisory system for livestock producers in the United States. This model predicts changes in body weight and condition for a broad range of livestock classes for cattle, sheep and goats. To test …

Irish Grassland Association: Delivering The Benefits From Grassland, S. Flanagan

IGC Proceedings (1977-2023)

The Irish Grassland Association (IGA) is Ireland's leading forum for discussing the science of grass and animal production, the economics and finances of dairy, beef cattle and sheep farm enterprises. Membership is 800 and is a lively mix of progressive farmers (70%), research scientists, advisers and agribusiness personnel. The IGA is a member of the European Grassland Federation and has close ties with the Ulster Grassland Society, Fermanagh Grassland Club and the British Grassland Society.

Drivers And Dynamics Of Phytoplankton Communities And Harmful Algal Blooms In Mountain Lakes, Lara Stephanie Jansen

Dissertations and Theses

Harmful cyanobacterial blooms (cyanoHABs) are a complex and widespread disturbance in freshwater water bodies, impacting water quality for wildlife and human populations. While cyanobacteria often bloom in warm lakes impacted by human development like agriculture, blooms are increasingly reported in cooler waters with limited development in the surrounding watershed. As much of cyanoHAB research has focused on lakes in highly developed watersheds, the understanding of factors leading to cyanobacteria dominance and blooms in the absence of major development remains limited. Mountain lakes can serve as ideal systems to study bloom-forming cyanobacteria in watersheds with minimal development. In addition, mountain lakes …

Proposing A Measure Of Ethicality For Humans And Ai, Alejandro Jorge Napolitano Jawerbaum

Electronic Theses and Dissertations

Smarter people or intelligent machines are able to make more accurate inferences about their environment and other agents more efficiently than less intelligent agents. Formally: ‘Intelligence measures an agent’s ability to achieve goals in a wide range of environments.’ (Legg, 2008)

In this dissertation we extend this definition to include ethical behaviour and we will offer a mathematical formalism and a way to estimate how ethical an action is or will be, both for a human and for a computer, by calculating the expected values of random variables. Formally, we propose the following measure of ethicality, which is computable, or …

Assessment Of Facultative Sulfur Reducing Bacteria In Acidic And Circumneutral Passive Remediation Systems Using A Novel Culturing Technique, Natalie Lamagna

Electronic Theses and Dissertations

Pollution resulting from abandoned mine drainage (AMD) is widespread across the nation and impacts thousands of miles of watersheds in Pennsylvania alone. AMD contaminants pose hazards to ecosystems and to human health by lowering the pH and by suspending toxic heavy metals in water. Sulfur reducing bacteria (SRB) are known to remove metals and sulfur species from mine drainage through the formation of metal sulfide precipitates and have been documented to raise the alkalinity of water. Therefore, it is necessary to understand the environmental conditions in which these microorganisms survive. Environmental samples were collected from a circumneutral and an acidic …

Her X'S And Y'S: Limericks About Women Mathematicians, Marion D. Cohen

Journal of Humanistic Mathematics

This poetry folder is just what its title says, limericks about women mathematicians. A few of them I’ve known personally, most not. There are, of course, many many many other women mathematicians; even though I write limericks prolifically, I could never finish writing about them all!

Exploring Set-Theoretic Practices Of Youth Engagement In Connective Journalism: What We Lose In School-Mathematical Descriptions, Alexandra R. Aguilar, Emma C. Gargroetzi, Lynne M. Zummo, Emma P. Bene

Journal of Humanistic Mathematics

Analyzing youth video submissions regarding COVID-19 to KQED’s ‘Let’s Talk About the Election’ website, we explore the mathematics these youth engaged in through their submissions without creating any explicit connection to school mathematical concepts or standards. Our focus is the students’ construction of sets (e.g. sets of nurses, doctors, American workers), as a means of creating connection with voters and other media authors through Marchi and Clark’s (2021) construct of connective journalism. We observe these youth constructing sets of varying sizes and reflecting on how these sets are contextualized within a larger political dialogue. We also attempt to rewrite part …

Communication In The Science-Policy Interface: Evidence From A Boundary Organization In Nebraska, Usa, Sechindra Vallury, Brian C. Chaffin, Samantha L. Hamlin, Craig R. Allen

School of Natural Resources: Faculty Publications

Boundary organizations have a crucial function in environmental governance by facilitating the processes through which scientists and decision-makers generate, exchange, evaluate, and utilize knowledge to identify societal problems, propose potential solutions, and make decisions on appropriate courses of action. This support for evidence-informed decision making is essential in addressing environmental challenges effectively. Despite the growing popularity of boundary organizations, there remains a significant challenge in designing information dissemination platforms to bridge the communication divide between scientific experts and non-experts. To address this gap, we used natural language processing tools to analyze the communication strategies of a specific boundary organization — …

Activation Of The Renin–Angiotensin–Aldosterone System Is Attenuated In Hypertensive Compared With Normotensive Pregnancy, Robin C. Shoemaker, Marko Poglitsch, Hong Huang, Katherine Vignes, Aarthi Srinivasan, Cynthia Cockerham-Morris, Aric Schadler, John Anthony Bauer, John O'Brien

UK CARES Faculty Publications

Hypertension during pregnancy increases the risk of adverse maternal and fetal outcomes, but the mechanisms of pregnancy hypertension are not precisely understood. Elevated plasma renin activity and aldosterone concentrations play an important role in the normal physiologic adaptation to pregnancy. These effectors are reduced in patients with pregnancy hypertension, creating an opportunity to define the features of the renin–angiotensin–aldosterone system (RAAS) that are characteristic of this disorder. In the current study, we used a novel LC-MS/MS-based methodology to develop comprehensive profiles of RAAS peptides and effectors over gestation in a cohort of 74 pregnant women followed prospectively for the development …

Statistical Methods For Assessing Treatment Effects On Ordinal Outcomes And Selecting Optimal Treatment On Survival Outcomes Using Observational Data., Huirong Hu

Electronic Theses and Dissertations

This dissertation consists of two projects investigating statistical methods in causal inference and personalized medication using observational data. In the first project, we propose a parametric marginal structural ordinal logistic regression model (MS-OLRM) to assess treatment effects on ordinal outcomes. Average treatment effect (ATE) is used to measure the difference of the mean outcomes if all patients would have been treated compared with the outcomes if they would not have been treated. Many statistical methods have been developed to estimate ATE when the outcome is continuous or binary. The methodology on assessing treatment effect for an ordinal outcome is less …

Intra-Gendered Perceptions And Adoption Of Climate-Smart Agriculture: Evidence From Smallholder Farmers In The Upper East Region Of Ghana, Kwabena Antwi, Philip Antwi-Agyei

Student Publications [Scholarly]

Climate-smart agriculture (CSA) remains a key strategy for sustaining agricultural systems and achieving food security and nutrition. Despite this, uncertainty remains on how intra-gendered dynamics influence its adoption in dryland farming systems. This study implements both quantitative and qualitative approaches including household surveys, key informant interviews, and focus group discussions to explore how intra-gender dynamics shape the perceptions and adoption of climate-smart agriculture in three selected communities (Katanga, Dakio, and Zonno) in the Bolgatanga East District of the Upper East Region of Ghana. Specifically, the study answers the following research questions: (i) What is the degree of change in rainfall …

Nutrient Responses To Hippuric Acid In Sheep Urine Applied To Pasture Soil Cores, Ethan Avery Collins

Graduate Theses and Dissertations

Hippuric acid is a breakdown product of tannins, which bind with proteins in the animal rumen and slow down protein metabolism, thus increasing nitrogen (N) retention in the animal. Increased hippuric acid concentration in bovine and ovine urine applied to soil may decrease rates of nitrification, denitrification, and nitrous oxide fluxes in pasture soils. Additionally, condensed tannins have increased rates of carbon mineralization when incorporated in humus and leaf litter. To evaluate effects of hippuric acid concentration, treatments of urine from sheep fed a tannin-supplemented diet, synthetic urine, or urea controls were applied to intact soil cores seeded with crabgrass …

Understanding The Factors Affecting Nebraskan Farmers’ And Landowners' Decision To Adopt Precision Agricultural Technologies And Programs, Corrin C. Winter

School of Natural Resources: Dissertations, Theses, and Student Research

Advisors: Andrew Little, Christopher Chizinski

To gain insights into the challenges faced by Nebraska farmers and landowners when adopting precision agriculture technologies, I analyzed data collected from a 2022 survey involving 7,503 participants, consisting of producers and farmland owners from across the state of Nebraska. The primary objective was to provide valuable insights for agencies seeking to improve their precision agriculture and conservation outreach efforts for the benefit of conservation and Nebraskan farmers and landowners. This study aimed to understand key factors influencing adoption behaviors by evaluating the constraints to precision agriculture adoption, assessing the impact of producer and landowner …

Depression, Anxiety, And Estimated Cardiorespiratory Fitness In College Students, Christian Ison

UNLV Theses, Dissertations, Professional Papers, and Capstones

Depression and anxiety disorders are two common mental health conditions worldwide. College students are considered a high-risk population for the development of these conditions. Improved cardiorespiratory fitness (CRF) has been shown to decrease depression and anxiety risk, symptoms, and severity but this relationship and the extent to which improved CRF can reduce these risks has yet to be examined in the college student population. Validated and reliable non-exercise estimated cardiorespiratory fitness (eCRF) algorithms could be used to identify relationships and associations with depression and anxiety severity levels among college students. The purpose of this study was to assess eCRF and …

Statistical Graph Quality Analysis Of Utah State University Master Of Science Thesis Reports, Ragan Astle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Graphical software packages have become increasingly popular in our modern world, but there are concerns within the statistical visualization field about the default settings provided by these packages, which can make it challenging to create good quality graphs that align with standard graph principles. In this thesis, we investigate whether the quality of graphs from Utah State University (USU) Plan A Master of Science (MS) thesis reports from the years 1930 to 2019 was affected by the rise of graphical software packages. We collected all data stored on the USU Digital Commons website since November 2021 to determine the specific …

A Mechanistic Examination Of Interspecific Competition Between Wild And Domestic Herbivores, Courtney Check

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Large herbivores, such as mule deer and cattle have similar life histories and likely compete for resources. However, quantifying the extent to which these species compete and the specific resources they compete for has proved challenging. My research examines if cattle influence deer abundance and behavior due to competition for forage, competition for shade, and/or by affecting the predation risk of deer. Using a grid of autonomous trail cameras, I was able to determine if cattle abundance influences local deer abundance in relation to specific resources and habitat features. Using GPS data from collared deer, I was also able to …

Biocrude Production From Lignin In Hydrothermal Medium: Effect Of Rapid Heating And Short Residence Time, Kyoko Hirayama

Civil & Environmental Engineering Theses & Dissertations

This study aims to address knowledge gaps in the production of valuable products from waste streams generated during lignocellulosic biofuel production. The primary objective is to develop a process that converts lignin, a byproduct of bioethanol refineries, into a sustainable biolubricant.

The first chapter examines recent advancements in synthesizing biolubricants and investigates their scalability. It explores innovative materials, catalysts, chemical modification approaches, and additives that have emerged in the field. A particular hurdle is the oxidative stability of biolubricants derived from plant oils, which are prone to autooxidation due to their C=C bonds. To overcome this, the study aims to …

The Role Of The New Zealand Grassland Association In Technology Interaction And Policy Evolution, M. W. Calder

IGC Proceedings (1977-2023)

The New Zealand Grassland Association (NZGA) aims for a two-way communication between grassland researchers and pastoral farmers on research findings and farming trends and opportunities. Annual conferences, special symposia, print and electronic publications as well as the web site are used to further these aims. Policy evolution is indirect, using the relationship with agribusiness sponsors and members to promote research objectives.

Activity Of Japanese Society Of Grassland Science, K. Sugawara, S. Saiga, K. Tateno, Y. Cai, N. Yoshida, T. Takamizo, M. Goto

IGC Proceedings (1977-2023)

The Japanese Society of Grassland Science (JSGS) was founded in 1954 for the purposes of progressing grassland and forage crop sciences and fostering grassland agriculture and better management of grassland for animal production in Japan. From the first, the members of JSGS have included interdisciplinary scientists from forage crop science, forestry, animal science, agribusiness and many related fields. In the 50 years since its foundation, JSGS has made large contributions to the progress of both science and industry in Japan. The number of JSGS members is now declining slightly, but there are still about 950 including 800 individual members and …

Comments On The Present Activity Of Czech Specialists In Grassland Cultivation, B. Cagaš

IGC Proceedings (1977-2023)

Unlike some other countries, there is no officially established forage crop or grassland society in the Czech Republic. This, however, does not mean that activity in this field is lacking. Several institutions are involved in the development of grassland research. These are predominantly: Grassland Commission of the Section of Plant Production of the Czech Academy of Agricultural Science, Forage Crop Commission of the Bohemian-Moravian Union of Plant Breeders, Bohemian-Moravian Association of Plant Breeding and Seed Production and Association of Grass and Clover Seed Growers. Members of these institutions are researchers and breeders of grasses and legumes, university lecturers from departments …

The Role Of Grassland Societies In The West Of Scotland, G. E. D. Tiley

IGC Proceedings (1977-2023)

Local grassland societies were first established in the United Kingdom in the 1950s, under the guiding hand of the national, British Grassland Society, itself founded in 1946. In the west of Scotland two local societies were formed: 1) the South West Scotland Grassland Society in 1962, covering the former counties of Ayrshire, Dumfries, Kirkcudbright and Wigtown; and 2) the Central Scotland Grassland Society for Lanark, Stirling, Renfrew, Dumbarton and Clackmannan. The declared aim of these two societies was to promote good grassland farming in all its aspects amongst members and to identify opportunities for improved grassland management, all to the …