Digital Commons Network^™

Effect Of Nitrogen On The Radiation Use Efficiency For Modelling Grass Growth, R. Lambert, A. Peeters

IGC Proceedings (1977-2023)

When nitrogen (N) is not at a sufficient level to permit maximum growth rate, dry matter production is reduced. Models of plant growth in relation to solar radiation intercepted by the crop have been largely used. According to these models, N deficiency can act on the leaf extension and thus on the quantity of radiation intercepted by the crop, but also by reducing the radiation use efficiency of the crop (RUE) (Bélanger, 1990). The effect of N on the RUE of ryegrass swards is determined and discussed.

The Meal Criterion Estimated In Grazing Dairy Cattle: Evaluation Of Different Methods, P. A. Abrahamse, D. Reynaud, J. Dijkstra, S. Tamminga

IGC Proceedings (1977-2023)

The meal criterion (MC) has been found a useful tool to pre-treat intake behaviour data in dairy cows. It was defined as the longest interval between bouts that belong to the same meal (Tolkamp & Kyriazakis, 1999), necessary to cluster bouts to meals. The method of Yeates et al. (2001) calculating the log_e-transformed intervals between bouts and using the Gaussian-Gaussian-Weibull (GGW) model to calculate the MC was found to provide the best estimation of the MC in biological as well as statistical terms. However, in grazing dairy cattle the MC-estimation has only been carried out by Rook …

Radiation Use Efficiency Of Ryegrass: Determination With Non Cumulative Data, R. Lambert, A. Peeters

IGC Proceedings (1977-2023)

The growth of a crop is generally described as biomass accumulation per unit time. Monteith (1977) developed a model of growth where biomass accumulation is related to solar radiation intercepted by the crop. This model has been largely used for different crops. The conversion factor between radiation absorbed or intercepted by the crop and the biomass production is called “radiation use efficiency” or “dry matter radiation quotient”. Radiation use efficiency (RUE) is usually calculated as the regression coefficient of the linear relationship between crop biomass measured repeatedly during growth and cumulated intercepted or absorbed solar radiation. Demetriades-Shah et al. …

Modelling The Digestibility Decrease Of Three Grass Species During Spring Growth According To The Age Of The Grass, The Thermal Age And The Yield, M. E. Salamanca, R. Lambert, M. Gomez, A. Peeters

IGC Proceedings (1977-2023)

The nutritive value of forage changes during growth. For the protein content, a general evolution curve was found with the yield increase (Salette & Lemaire, 1984). The digestibility of the organic matter decreases during growth as cellulose and lignin content increase. Regrowth age is the main factor, which explains the digestibility decrease (Demarquilly & Jarrige, 1981). The crop age can be expressed in number of growth days but also in thermal age (cumulated temperature). We compared the digestibility change of three grass species during spring growth for two years as a function of yield increase, thermal age or number of …

Visual Modelling Of Alfalfa Growth And Persistence Under Grazing, S. R. Smith Jr., L. Muendermann, A. Singh

IGC Proceedings (1977-2023)

A ‘virtual’ alfalfa plant model was developed at the University of Manitoba in Canada as part of a comprehensive grazing research project. This model shows an alfalfa plant ‘growing’ on a computer screen and the plant’s response to grazing (similar to time-lapse photography). The original model was constructed by Singh (2005) to show the research potential of visually modelling alfalfa plant growth. The ability to visually ‘grow’ a plant on a computer screen also offers tremendous opportunities for teaching and extension. Detailed morphological measurements were used in the construction of Singh’s model, based on single plants subjected to the following …

A New Agro-Meteorological Simulation Model For Predicting Daily Grass Growth Rates Across Ireland, R. P. O. Schulte

IGC Proceedings (1977-2023)

Grass growth rates and herbage yields depend on weather conditions, soil characteristics and grassland management and differ from year to year and from site to site. In the past, grass growth has been predicted using both mechanistic and statistical models. The accuracy of mechanistic models is commonly insufficient for practical application, while statistical models generally apply to one test site only (e.g. Han et al., 2003). In this paper a semi-empirical grass growth model is presented which is numerically accurate, but which can be applied to contrasting sites across Ireland at the same time.

A Farmer-Based Decision Support System For Managing Pasture Quality On Hill Country, I. M. Brookes, D. I. Gray

IGC Proceedings (1977-2023)

Despite considerable effort to promote formal feed budgeting in New Zealand, survey data suggests it is only adopted by 20% of farmers (Nuthall & Bishop-Hurley, 1999). Recent work (Gray et al., 2003) has identified that farmers may use a different approach - micro-budgeting - to manage feed. Rather than operate at a whole farm level, micro-budgeting focuses at the paddock level. This paper describes micro-budgeting as used by a high performing hill country sheep and cattle farmer to manage pasture quality over spring and a decision support model developed to help other farmers undertake this process

Pâtur’In: A User-Friendly Software Tool To Assist Dairy Cow Grazing Management, L. 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 …

Understanding Livestock Grazing Impacts: A Decision Support Tool To Develop Goal-Oriented Grazing Management Strategies, S. J. Barry, K. Guenther, G. Hayes, R. Larson, G. Nader, M. Doran

IGC Proceedings (1977-2023)

Managing grasslands in the western United States has become much more complex over the last few decades. A century ago the goal was to survive as a livestock producer, and grassland management involved using forage effectively and overcoming obstacles such as predators and shortages of water and feed. Today the successful grassland manager also needs to consider the diversity and health of the ecosystem as a whole. Livestock grazing can negatively and/or positively affect riparian areas, sensitive plants, and endangered wildlife. Since the impact on a specific factor will vary depending on the timing, intensity and class of livestock grazed, …

Enhancing Grasslands Education With Decision Support Tools, H. 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™ (Moore et al., 1997) and GrazFeed™ (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 level. We …

Prophages Encode And Disseminate Bacterial Immune Systems, Amelia K. Schmidt

UM Graduate Student Research Conference (GradCon)

Bacteria are under constant threat of infection by viruses called bacteriophages (phages).

As a result, bacteria have evolved diverse phage defense systems; however, these defenses are very specific and effectively defend against a narrow range of phages. I have discovered that the filamentous Pf phages which chronically infect the formidable bacterial pathogen Pseudomonas aeruginosa encode diverse phage defense systems. Infection by a competing phage mobilizes these systems, allowing defense systems to fluctuate in dominance in response to the ever-changing pressure of phage predation.

Parasitic Infection In A Social Carnivore: T. Gondii Exposure Increases Risky Decision Making In Gray Wolves, Connor J. Meyer, Kira A. Cassidy, Erin Stahler, Ellen Brandell, Colby B. Anton, Daniel Stahler, Douglas W. Smith

UM Graduate Student Research Conference (GradCon)

Toxoplasma gondii is a protozoan parasite capable of infecting any warm-blooded species yet, requires a feline definitive host to sexually reproduce. Experimental studies indicate that T. gondii infection increases an individual’s risky decision-making but, due to the intensive data collection and large samples sizes necessary, T. gondii’s role in ecosystem processes is understudied.

We sought to understand the role in which T. gondii exposure affects gray wolf decision-making in Yellowstone National Park. To achieve this, we used 25 years of wolf serological and behavioral data to build generalized linear mixed models (GLMMs) to test for a change in behavior of …

Beaver Dam Analogs Change Macroinvertebrate Communities In Headwater Streams, Western Montana, Michelle E. Fillion

UM Graduate Student Research Conference (GradCon)

Starting in the 17^th century, beavers were nearly eradicated from their historic range. Though today their populations are improving, the lack of beaver dams in aquatic systems has left a lasting impact on the environment. As a result, managers of freshwater systems have turned to beaver dam analogs (BDAs) as one technique for stream restoration. BDAs are human constructed structures designed to mimic natural beaver dams and their geomorphic, hydrologic, and ecological effects. Though BDAs have proven to be a useful restoration technique, there has been little research on how they influence macroinvertebrate communities, which serve as a vital …

Seeding Resilience: An Examination Of The Impacts Of A Seed Saving Network In Western Montana, Christina Leas

UM Graduate Student Research Conference (GradCon)

Informal seed saving continues even in the context of an increasingly industrialized and globalized agricultural system. While some scholarship has focused on informal seed saving practices that continue to thrive in the global South, few studies have examined the dynamics of these practices in the global North, particularly in the American West. This thesis utilizes a resilience framework to assess a seed saving network and its impacts in western Montana, specifically the Bitterroot and Missoula Valleys. Two questions guide the inquiry: 1) How do significant actors connect within the seed saving network of the Missoula and Bitterroot Valleys, and 2) …

A Farmer Friendly Feed Budget Calculator For Grazing Management Decisions In Winter And Spring, M. Curnow, M. W. Hyder

IGC Proceedings (1977-2023)

The Western Australian (WA) environment is Mediterranean with annual legume/grass pastures and a 6 month growing season. In autumn where over grazing can impact pasture establishment and in spring, prior to senescence, when under grazing can mean significant losses of efficiency are crucial times for grazing management. Pasture utilisation is typically low (25-35%) due to conservative stocking regimes; key to increasing productivity is increasing pasture utilisation (Grimm, 1998). Increased levels of productivity require farmer sophistication in the way they feed budget. To this end, satellite technology is being used to provide farmers in southern Australia with weekly estimates of pasture …

Simulation Of Pasture Phase Options For Mixed Livestock And Cropping Enterprises, L. Salmon, A. D. Moore, J. F. Angus

IGC Proceedings (1977-2023)

In southern Australia, 50% of grain-producing farms also run beef and/or sheep enterprises. Legume pasture leys are used to replace soil nitrogen and manage crop disease risks. Deep-rooted perennials, predominantly lucerne (Medicago sativa), are replacing annual Trifolium subterraneum-based leys to increase pasture production. They also have the environmental benefits of limiting soil acidity, rising water tables and dryland salinity. After recent droughts depletion of soil water by lucerne has penalised wheat yields. Decision support tools can help farmers evaluate the long-term effects of grazed annual and perennial leys on animal and crop production at the whole farm …

Grasscheck: Monitoring And Predicting Grass Production In Northern Ireland, P. D. Barrett, A. S. Laidlaw

IGC Proceedings (1977-2023)

No abstract provided.

Effect Of Strategy Of Forage Supplementation And Of Turnout Date In A Medium Stocking Rate System On The Main Characteristics Of Dairy Cows Grazing, P. Defrance, L. Delaby, J. M. Seuret, M. O'Donovan

IGC Proceedings (1977-2023)

Having a stocking rate of 2.9 cows per hectare of grassland (35 ares/cow) in Brittany offers many options for turnout date and forage supplementation strategies. For a farmer, knowing the consequences of the different options during the course of the grazing season makes grazing management decisions easier. As experiments on grazing management require considerable resources and are hardly generalisable, various spring scenarios have been tested using a dynamic decision support system, Pâtur’IN (Delaby et al., this volume).

Grass Growth Profiles In Brittany, P. Defrance, J. M. Seuret, L. Delaby

IGC Proceedings (1977-2023)

For farmers, knowing the local grass growth profile and the possible variations between years is very helpful in managing grazing. Indeed, the comparison with herd needs and anticipated farm cover change allows decisions to be made that will maintain the cover at the desired level. This paper proposes a ten-days grass growth profile corresponding to Brittany’s different conditions of soil, climate and pasture management.

Using The Grassgro Decision Support Tool To Evaluate The Response In Grazing Systems To Pasture Legume Or A Grass Cultivar With Improved Nutritive Value, H. Dove, J. R. Donnelly

IGC Proceedings (1977-2023)

Decision support tools (DST) based on models of grazing systems allow the evaluation of changes in enterprise management on productivity and profitability. The Grassgro DST (Moore et al., 1997) uses historical weather data on a daily time step to simulate pasture growth and the resultant productivity of either grazing sheep or cattle. Different pasture species are represented within a parameter set that describes the response of pasture species to their environment. Manipulation of these parameters provides a means of evaluating, a priori, the likely responses of livestock production to ‘improved cultivars’. We report the results of simulations conducted …

Medical School Watercooler Newsletter - February 24, 2023, Lindsey Lyle

Watercooler Newsletter

This is the February 24, 2023 edition of the Frederick P. Whiddon College of Medicine's newsletter - Watercooler.

Contents include:

• Reed joins office of research education and training
• GHHS members observe Solidarity week
• Fundraising event for Ukraine set for Feb. 24
• Alumni Spotlight: Nita Landry, M.D. '07

The Beacon, February 24, 2023, Beacon Staff

The Beacon, 2022-2023

Unsung Heroes: Mere Reyes; What is student government at NW?; Rebecca Black's debut dawns new day; Newest "Ant-Man" installation falls short; Senior Spotlight: Chloe Tschetter; Ads and halftime show triumph Superbowl; NW reflects on Ash Wednesday Services; Maintenance worker goes above and beyond; How do college students spend their money?; NW Student Government; Prehistoric Dino Controversy; NW Athletes in Intramurals at NW; Birds Can Fly, But Raiders Can Fly Higher; Chaotic Cool: Library Craig Fines Defenders; Jennifer Boeve Ruling the NW Raider Softball Roost; Professor prepares for a new journey; Flapjacks, fellowship and friendly competition

Simple Mathematical Equations For Calculating Oxidation Number Of Organic Carbons, Number Of Transferred Electrons, Oxidative Ratio, And Mole Of Oxygen Molecule In Combustion Reactions, Pong Yuen, Cheng Man Diana Lau

Faculty Publications

The oxidation number and number of transferred electrons are two paramount parameters in the study of redox reactions. Their calculations are both important and challenging. The oxidation number of organic carbons is used in organic chemistry, biochemistry, and applied chemistry. Combustion reaction is a classical type of redox reaction, in which the oxygen molecule (O2) is the oxidizing agent. In this article, the integration of three sets of relations is explored by using the method of balancing organic combustion: (i) number of transferred electrons and oxidation number of organic carbons, (ii) mole of oxygen molecule and number of transferred electrons, …

Caregivers’ Views On Cannabis Use For Their Children With Autism, Taylor Sivori, Maclain Capron, Daniel E. Graves, Jill Harris, Roseann C. Schaaf

Jefferson Autism Center of Excellence Faculty Papers

Background: Autism is a neurodevelopmental disorder impacting 1 in 44 children that is characterized by decreased social communication and problem behaviors. Despite the increasing accessibility of cannabis, there is limited guidance about its use and usefulness for autism. The purpose of this study is to query caregivers of autistic children about their experience, knowledge and interest in medical cannabis use for their children.

Method: Survey methodology was used to query caregivers of autistic children between ages five to ten years. Informants recruited through a large children’s hospital in New Jersey and the Autism Speaks website. Descriptive analyses of frequencies and …

Microfluidic Concurrent Assessment Of Red Blood Cell Adhesion And Microcapillary Occlusion: Potential Hemorheological Biomarkers In Sickle Cell Disease, Yuncheng Man, Douglas H. Wu, Ran An, Karamoja Monchamp, Utku Goreke, Zoe Sekyonda, William J. Wulftange, Chiara Federici, Allison Bode, Lalitha V. Nayak, Umut A. Gurkan

Faculty Scholarship

Deformability and non-adherence are two fundamental functional properties of red blood cells (RBCs), which allow them to move unimpeded through the microvasculature. In sickle cell disease (SCD), polymerization of abnormal sickle hemoglobin leads to decreased deformability and increased membrane adhesiveness in RBCs. This contributes to abnormal blood vessel occlusion, which is central to the underlying pathophysiology. RBC deformability and adhesiveness are, therefore key hemorheological biomarkers in characterizing disease states as well as in evaluating novel therapeutics. To date, these important interrelated biomarkers have been assessed in distinct laboratory assays, without integration or concurrent assessment in vitro. To this end, we …

The Environmental Conditions, Treatments, And Exposures Ontology (Ecto): Connecting Toxicology And Exposure To Human Health And Beyond., Lauren E Chan, Anne E Thessen, William D Duncan, Nicolas Matentzoglu, Charles Schmitt, Cynthia J Grondin, Nicole Vasilevsky, Julie A Mcmurry, Peter N Robinson, Christopher J Mungall, Melissa A Haendel

Faculty Research 2023

BACKGROUND: Evaluating the impact of environmental exposures on organism health is a key goal of modern biomedicine and is critically important in an age of greater pollution and chemicals in our environment. Environmental health utilizes many different research methods and generates a variety of data types. However, to date, no comprehensive database represents the full spectrum of environmental health data. Due to a lack of interoperability between databases, tools for integrating these resources are needed. In this manuscript we present the Environmental Conditions, Treatments, and Exposures Ontology (ECTO), a species-agnostic ontology focused on exposure events that occur as a result …

The Effect Of Language Type And Perceived Controllability On Stigma And Compassion, Maddie Leake, Christine Mcgrath, Trudy Mickel, Claire Shaver, Gina A. Paganini, E. Paige Lloyd

DU Undergraduate Research Journal Archive

Previous research suggests that mental health stigma creates significant barriers to treatment seeking and adherence, diminishes treatment outcomes, and motivates social rejection towards people experiencing mental illness; by contrast, compassion seems to offer protective effects, improving treatment outcomes and helping behavior. The current work extends the established literature by experimentally examining the independent and interactive effects of two factors theorized to influence stigma and compassion: controllability and language. Participants read vignettes about hypothetical mental illnesses explained with a genetic attribution (indicating low controllability) or a behavioral attribution (indicating high controllability) and completed measures of perceived controllability, stigma, and compassion. We …

Gottman Processes And Couple Outcomes While Navigating Infertility, Clayton Brigance

Dissertations

Infertility remains one of the most difficult relational contexts for couples. However, some research suggests that some couples actually increase their overall satisfaction in their relationship through infertility due to a deeply shared emotional experience. To the knowledge of the author of this dissertation, no studies exist which explain how couples arrive at their relational outcomes through the experience of infertility. These studies within this dissertation add to the present literature by explaining how couples may arrive at their relational outcome through the lens of Gottman Method Couple Therapy (GMCT). For both studies presented here, 902 participants were recruited through …

Data From: Mechanisms Of Gill-Clogging By Hagfish Slime, Luke Taylor, Gaurav Chaudhary, Gaurav Jain, Andrew Lowe, Andre Hupe, Atsuko Negishi, Yu Zeng, Randy Ewoldt, Douglas Fudge

Biology, Chemistry, and Environmental Sciences Faculty Data Sets

Abstract of Proc. Roy. Soc. article:

Hagfishes defend themselves from gill-breathing predators by producing large volumes of fibrous slime when attacked. The slime’s effectiveness comes from its ability to clog predators’ gills, but the mechanisms by which hagfish slime clogs are uncertain, especially given its remarkably dilute concentration of solids. We quantified the clogging performance of hagfish slime over a range of concentrations, measured the contributions of its mucous and thread components, and measured the effect of turbulent mixing on clogging. To assess the porous structure of hagfish slime, we used a custom device to measure its Darcy permeability. We …

Volume Cxlii, Number 15, February 24, 2023, Lawrence University

The Lawrentian

No abstract provided.