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Synergies Of Microecology And Macroecology Elicit Insights For Creation Care, David Warners, John T. Wertz
Synergies Of Microecology And Macroecology Elicit Insights For Creation Care, David Warners, John T. Wertz
University Faculty Publications and Creative Works
This article reports on a collection of microecological and macroecological insights that emerged from extended conversations between Calvin University professors David Warners, a botanist concentrating in restoration ecology, and John Wertz, a micro-biologist specializing in microbial ecology. Classic descriptions of ecology identify biological interactions as happening at the ecosystem, community, or population level. And yet, ecological interactions are very much occurring at the microbial level as well. Furthermore, microbial-level interactions frequently influence the quality and character of macroecological relationships and vice versa. Allowing ecological principles to be applied across all life forms broadens our comprehension of interactions that are happening …
A Review On Credit Card Electronic Fraud Detection Methodologies, Titilayo Mary Sayikanmi, Ibrahim Adepoju Adeyanju, Bolaji Abigail Omodunbi
A Review On Credit Card Electronic Fraud Detection Methodologies, Titilayo Mary Sayikanmi, Ibrahim Adepoju Adeyanju, Bolaji Abigail Omodunbi
Mansoura Engineering Journal
Credit card fraud remains a critical and escalating challenge within the global financial ecosystem, driving substantial annual losses and necessitating the continuous evolution of detection methodologies. This paper presents a systematic literature review, conducted via the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework, which comprehensively analyzes the state-of-the-art in electronic credit card fraud detection. Through a rigorous examination of 49 high-quality studies, this review maps the methodological evolution from traditional rulebased systems and statistical models to advanced artificial intelligence techniques, including machine learning, deep learning, and graph-based approaches. The analysis reveals that while individual methods possess distinct advantages …
Estimates Of Insecticide Performance Against Selected Insect Pests Of Cotton, Corn, Sorghum, And Soybeans Across The Cotton Producing States Of The United States, 2025, D. Cook, S. Graham, B. Thrash, N. Bateman, G. Studebaker, I. Esquivel, P. Roberts, D. Buntin, D. D. Kerns, J. Villegas, W. D. Crow, T. B. Towles, C. Floyd, D. Reisig, A. Farris, J. K. Greene, F. Reay-Jones, S. Brown, D. L. Kerns, S. Vyavhare, T. Mays, K. Siders, B. Easterling, S. Biles, T. Bryant
Estimates Of Insecticide Performance Against Selected Insect Pests Of Cotton, Corn, Sorghum, And Soybeans Across The Cotton Producing States Of The United States, 2025, D. Cook, S. Graham, B. Thrash, N. Bateman, G. Studebaker, I. Esquivel, P. Roberts, D. Buntin, D. D. Kerns, J. Villegas, W. D. Crow, T. B. Towles, C. Floyd, D. Reisig, A. Farris, J. K. Greene, F. Reay-Jones, S. Brown, D. L. Kerns, S. Vyavhare, T. Mays, K. Siders, B. Easterling, S. Biles, T. Bryant
Midsouth Entomologist
Annually the members of the National Cotton States Arthropod Pest Management Working Group estimate insecticide and insect trait performance against selected insect pests in cotton, corn, sorghum, and soybeans across the cotton growing states. These estimates are based on commonly used/recommended rates and from observations collected through field experiences and replicated research trials. Results are summarized by region including the Southeast, MidSouth, West, and across all regions (U.S.). States comprising regions include Alabama, Florida, Georgia, North Carolina, South Carolina, and Virginia (Southeast); Arkansas, Louisiana, Mississippi, Missouri, and Tennessee (Mid-South); and Arizona, California, Kansas, New Mexico, Oklahoma, and Texas (West). Not …
The Cultivation Of Public Perception: Cultivated Meat Narratives And Misinformation On Tiktok, Anna M. Balkus
The Cultivation Of Public Perception: Cultivated Meat Narratives And Misinformation On Tiktok, Anna M. Balkus
Graduate Masters Theses
Cultivated meat is an emerging tissue engineering technology that has the potential to address major issues threatening food systems, including climate change, rapid population growth, and the spread of disease. Among technical challenges, public perception remains a significant barrier for the widespread adoption of cultivated meat. While social media has transformed communication globally, it has simultaneously contributed to corrupt online environments infected with misinformation—unintentional inaccuracies that differ from disinformation, which is spread with the intent to mislead. The way the public receives and digests information regarding new food technologies, like cultivated meat, will be shaped by their social media environment. …
Intervention Levers For Stunting Reduction In Indonesia: Evidence From The 2023 Indonesian Health Survey Data, Iwan Ariawan, Hafizah Jusril, Zahra Izza Afifa, Azka Fitri, Elmarizha Sekar Utami, Mikail Hasan, Dwi Puspasari
Intervention Levers For Stunting Reduction In Indonesia: Evidence From The 2023 Indonesian Health Survey Data, Iwan Ariawan, Hafizah Jusril, Zahra Izza Afifa, Azka Fitri, Elmarizha Sekar Utami, Mikail Hasan, Dwi Puspasari
Kesmas
Stunting remains the largest public health challenge among macro-nutrition problems in Indonesia, affecting almost a quarter of children under five in 2023. The prevalence is considered high according to the World Health Organization standard. This study analyzed 15 aggregated provincial variables from the 2023 Indonesian Health Survey using Structural Equation Modeling (SEM), focusing on determinants of stunting among children under two to identify primary intervention levers. Findings indicated that intervention urgency should focus on the first 1,000 days, particularly the steep increase in stunting prevalence observed in the 12–24-month age range. While the highest prevalence is in Eastern provinces (e.g., …
Vergence Task-Based Neural Pathways With Binocularly Normal Vision And Comorbid Persistent Post-Concussive Symptoms -Convergence Insufficiency, Ayushi Sangoi
Dissertations
Binocular dysfunctions are more prevalent in the persistent post-concussive symptoms (PPCS) population than in the general population. The most prevalent binocular disorder is convergence insufficiency (CI), affecting 3-17% of the general population and up to 10 times as many people with PPCS. CI makes it difficult to fuse or maintain fusion on targets at near, and its symptoms include double or blurry vision and headaches when performing close-range tasks such as reading, which can exacerbate PPCS symptoms. Given controversy over the subjectivity and effectiveness of diagnostic tools and symptom surveys for both PPCS and CI, understanding why CI has high …
Transcranial Ac Modulation Of Cerebellar Nuclear Activity In Awake Animals, Nuran Kavakli
Transcranial Ac Modulation Of Cerebellar Nuclear Activity In Awake Animals, Nuran Kavakli
Dissertations
Entrainment of cerebellar nuclear (CN) cells via cerebellar transcranial alternating current stimulation (ctACS) has been reported in animals under ketamine/xylazine anesthesia. Our main objective was to demonstrate modulation of CN activity in unanesthetized, freely moving animals using ctACS. Multi-channel carbon-fiber electrodes were implanted into the interpositus nucleus for recording multi-unit (MU) activity, and thin-film electrodes were implanted subcutaneously over the posterior cerebellum for stimulation. A frequency-domain-based metric was developed to quantify modulation from MU signals. The results demonstrated modulation in a wide range of frequencies (4 Hz-300 Hz) as in anesthetized animals. In contrast, the amplitude of the peak in …
The Effect Of Incompatibility Types On The Escalation Of Global Armed Conflicts, Michael Haratua Rajagukguk, Ruben Cornelius Siagian Rcs
The Effect Of Incompatibility Types On The Escalation Of Global Armed Conflicts, Michael Haratua Rajagukguk, Ruben Cornelius Siagian Rcs
Journal of Terrorism Studies
Global armed conflicts show variations in intensity influenced by the type of issue incompatibility. This study aims to analyze the influence of territorial, ideological, and combined incompatibilities on the probability of high-intensity conflict escalation, as well as its implications for conflict mitigation strategies. Global conflict dyadic data were analyzed using a multilevel logistic regression model with controls for time, region, and conflict type. The results show that ideology-based conflicts have a lower probability of reaching high intensity than territorial conflicts (OR ≈ 0.51, p < 0.05), while conflicts with a combination of ideology and territory tend to be at greater risk of high escalation (AM effect ≈ +26.6 points), although the effect is not yet statistically significant. Temporal analysis shows a downward trend in conflict intensity over time, especially in the post-Cold War period, while regional effects and conflict types show significant variation. These findings fill a gap in the literature on the dual interaction of ideological and territorial claims, showing that the highest escalation of violence occurs when symbolic and material dimensions are intertwined. In conclusion, conflict escalation is more influenced by a combination of issues and structural characteristics of conflict than by ideology alone. The novelty of this research lies in the identification of the strengthening effect of dual incompatibility and the downward trend in conflict intensity after the Cold War, which emphasizes the importance of a relational and temporal context-based mitigation approach in global conflict management.
Pickleweed In The Disappearing Marsh: Population Genetics & Metal Accumulation In Salicornia Depressa, Alice Kaisla
Pickleweed In The Disappearing Marsh: Population Genetics & Metal Accumulation In Salicornia Depressa, Alice Kaisla
Graduate Doctoral Dissertations
Salicornia is a genus of succulent halophytes found in salt marshes around the world. Salicornia species have a remarkably high tolerance for heavy metal pollution and have been shown to accumulate high concentrations of heavy metals in their tissue under experimental conditions. As a result, they are both a useful system for studying evolution in polluted coastlines and a potential candidate for use in phytoremediation. My research focuses on Salicornia depressa, known as pickleweed, a species commonly found in marshes along the heavily urbanized and industrialized New England coast. I investigate genetic diversity and population structure in S. depressa populations …
Adapting Population Genetics, Practice, And Policy For Plant Conservation In A Changing World, Cooper M. Kimball-Rhines
Adapting Population Genetics, Practice, And Policy For Plant Conservation In A Changing World, Cooper M. Kimball-Rhines
Graduate Doctoral Dissertations
Biodiversity conservation is an inherently interdisciplinary goal that requires effective collaboration among academics, ecosystem managers, policymakers, and other stakeholders. Codesigning research with these groups ensures experiments are useful and improves adoption of policy and practice recommendations while advancing our understanding of basic science. This dissertation explores the power of codesigned research in shaping plant conservation strategies using stakeholder engagement, causal inference, demographic modeling, and multi-omic sequencing techniques. In chapter 1 I discuss the history of New England ecosystems and the need for research-driven changes to plant conservation policy and practice in the face of global change. In chapter 2, I …
Investigation Of Environmental Influences On Multiple Sclerosis: A Study For Egypt’S Health, Noha Ezzaldin Alziny Ali
Investigation Of Environmental Influences On Multiple Sclerosis: A Study For Egypt’S Health, Noha Ezzaldin Alziny Ali
Theses and Dissertations
Background: Multiple sclerosis (MS) is a complex, chronic neuroinflammatory disease influenced by both genetic and environmental factors. While global research has identified potential environmental influences, most evidence comes from Western populations, creating a significant knowledge gap for regions like Egypt, which has witnessed a dramatic rise in MS prevalence over recent decades. This study hypothesized that Egyptian MS patients exhibit a distinct biological signature in their blood, characterized by an imbalance in essential and toxic trace elements (the metallome) and alterations in stress-response biomarkers associated with neuroaxonal injury and cellular stress. Objective: This study aimed to comprehensively profile and compare …
Is Trimethylamine N-Oxide A Friend, Foe, Or Hormetic Agent In Patients With Parkinson’S Disease: A Focused Review Of One Microbial Metabolite, Abraham B. Alton
Is Trimethylamine N-Oxide A Friend, Foe, Or Hormetic Agent In Patients With Parkinson’S Disease: A Focused Review Of One Microbial Metabolite, Abraham B. Alton
Student Works
This review synthesizes recent literature examining trimethylamine N-oxide (TMAO) synthesis and its potential role in Parkinson’s Disease (PD) pathology. An increase in TMAO plasma and CSF concentration is associated with PD progression and severity. TMAO biosynthesis is a two-step process. First, precursors including carnitine and choline are converted to trimethylamine (TMA) by gut microbes. Second, TMAO is oxidized to TMAO in the liver. Once absorbed into circulation TMAO crosses the blood brain barrier and may influence PD disease pathology by increasing neuroinflammation and astrocyte activation and damaging the cerebral lymphatic system. These mechanisms may contribute to the cognitive and motor …
Working Out Your Self-Image: Strength, Self-Esteem, And Human Flourishing, Kingston K. Christie
Working Out Your Self-Image: Strength, Self-Esteem, And Human Flourishing, Kingston K. Christie
Honors Projects
This project integrates empirical research in exercise science with theological anthropology to examine the psychological effects of resistance training and the meaning of strength within a Christian framework of human dignity and flourishing. The empirical component investigated the effects of a four-week progressive resistance training intervention on global self-esteem and physical self-concept among undergraduate university students with moderate-to-low baseline self-esteem. Eleven participants (N = 11; 20.15 ± 1.52 yrs) completed the Rosenberg Self-Esteem Scale (RSES) and Physical Self-Description Questionnaire Short Form (PSDQ-S) before and after the intervention, with muscular strength assessed via submaximal testing across the squat, bench press, deadlift, …
Rocatinlimab As A Novel Treatment Strategy For Atopic Dermatitis, Haylee Whyde, Evan Blazek, Macy Davis, Parker George, Alex Lowery, Connor Dains, Brenna Hissong, David Koh
Rocatinlimab As A Novel Treatment Strategy For Atopic Dermatitis, Haylee Whyde, Evan Blazek, Macy Davis, Parker George, Alex Lowery, Connor Dains, Brenna Hissong, David Koh
Pharmacy and Wellness Review
Atopic dermatitis is a common chronic inflammatory skin disease that affects millions of children and adults in the United States. Atopic dermatitis is characterized by recurrent pruritus, erythema, and relapsing symptoms that can significantly impair quality of life. The pathophysiology of atopic dermatitis involves epidermal barrier dysfunction, immune dysregulation, and genetic susceptibility. Atopic dermatitis guidelines follow a stepwise approach that begins with a severity assessment, trigger avoidance, and nonpharmacologic and pharmacologic treatments. First-line therapies include topical corticosteroids (TCSs), topical calcineurin inhibitors (TCIs), and emollients. Crisaborole and topical ruxolitinib are used for mild-to-moderate disease when prior therapy has been inadequate. Monoclonal …
Fda Approval Of Tradipitant: A Novel Approach To Motion Sickness Treatment, Haley Brown, Jennifer Cao, Allie Honigford, Leah Heitkamp, Sarah Hiett, Connor Dains, Brenna Hissong, Manoranjan D'Souza
Fda Approval Of Tradipitant: A Novel Approach To Motion Sickness Treatment, Haley Brown, Jennifer Cao, Allie Honigford, Leah Heitkamp, Sarah Hiett, Connor Dains, Brenna Hissong, Manoranjan D'Souza
Pharmacy and Wellness Review
Motion sickness is a prevalent neurophysiological condition affecting approximately one-third of the worldwide population, resulting from sensory mismatch and the brain’s internal model of motion. It is characterized by nausea, vomiting, dizziness, and autonomic symptoms during exposure to actual or virtual motion, which may significantly impair daily functioning and quality of life. Current guidelines recommend the prevention and treatment of motion sickness through pharmacologic, herbal, and non-pharmacologic strategies. Scopolamine and first-generation antihistamines are effective pharmacologic options, while ginger has demonstrated some benefit in reducing symptoms as an herbal option. Non-pharmacologic interventions such as habituation training, behavioral techniques, and sensory strategies …
Evaluating The Market Withdrawal Of Andexanet Alfa, Jordyn Linfield, Addisyn Cooper, Alexander Defranco, Emma Gerding, Jessica Kelley, Tyler Henney, Connor Dains, Brenna Hissong, Brittany Bates
Evaluating The Market Withdrawal Of Andexanet Alfa, Jordyn Linfield, Addisyn Cooper, Alexander Defranco, Emma Gerding, Jessica Kelley, Tyler Henney, Connor Dains, Brenna Hissong, Brittany Bates
Pharmacy and Wellness Review
The coagulation cascade comprises intrinsic, extrinsic, and common pathways that converge when thrombin converts fibrinogen (factor I) into fibrin, leading to fibrin mesh formation, stabilization of the platelet plug, and ultimately thrombus formation. Inhibition of the coagulation cascade can be achieved with a variety of anticoagulant medications, including direct oral anticoagulants (DOACs). The mechanism of action of DOACs is to inhibit either factor Xa or thrombin. Reversal of anticoagulation remains an important clinical consideration when managing patients on DOACs who experience serious bleeding events. Andexanet alfa is a recombinant, modified human factor Xa protein previously indicated for patients receiving rivaroxaban …
Fda Approval Of Etripamil For The Treatment Of Paroxysmal Supraventricular Tachycardia, Kiley Devoll, Daniella Egbujor, Katy Grainger, Katherine Cook, Victoria Niese, Connor Dains, Brenna Hissong, Andrew Roecker
Fda Approval Of Etripamil For The Treatment Of Paroxysmal Supraventricular Tachycardia, Kiley Devoll, Daniella Egbujor, Katy Grainger, Katherine Cook, Victoria Niese, Connor Dains, Brenna Hissong, Andrew Roecker
Pharmacy and Wellness Review
Paroxysmal supraventricular tachycardia (PSVT) is characterized by sudden, brief, intermittent episodes that result in a heart rate of 150 to 250 beats per minute (bpm). PSVT is difficult to diagnose, making proper treatment challenging. According to the 2015 American Heart Association (AHA)/American College of Cardiology (ACC)/Heart Rhythm Society (HRS) guidelines, current pharmacologic recommendations for PSVT include adenosine, verapamil, diltiazem, or nonpharmacologic vagal maneuvers.1 These treatments each have a variety of adverse effects, contraindications, and dosing considerations, which highlight a need for novel therapies for the acute treatment and maintenance of PSVT.1 The NODE-301 trial assessed the safety and …
Impact Of Package Dimension Changes On The Consumer’S Perception Of Ready-To-Eat Meal Serving Size, Greg Roskos, Koushik Saha
Impact Of Package Dimension Changes On The Consumer’S Perception Of Ready-To-Eat Meal Serving Size, Greg Roskos, Koushik Saha
Journal of Applied Packaging Research
Consumers increasingly scrutinize changes in food packaging, particularly in the context of “shrinkflation,” yet little empirical work has examined whether small dimensional changes in primary packaging affect perceived value when product weight is held constant. This study investigates the impact of minor tray dimension changes on consumers’ perception of serving size and product quality for ready-to-eat (RTE) frozen meals. Three single-compartment tray formats were evaluated: a control tray, a larger-volume tray (~18% increase), and a hybrid tray with an intermediate volume (~8% increase). All trays contained identical net product weight. Thirty-six untrained panelists from a local community participated in a …
Patents And Technology Evolution: Altering Innovations And Innovators Via Patent Influences, Richard Gruner
Patents And Technology Evolution: Altering Innovations And Innovators Via Patent Influences, Richard Gruner
Georgia Journal of Law & Technology
Technologies improve primarily through evolutionary change not rational optimization. New technologies emerge as attempts to solve practical problems, the technologies are tested in marketplaces to determine if they are superior in cost and function to alternatives, and those that fare well in the testing gain widespread adoption. Widely adopted technologies, and their problems, form the basis for the next round of technology improvements and evolution. Through these steps, evolutionary processes lacking rational direction can generate changing technologies matched to the desires and problems of present society.
As they operate to advance diverse technologies, evolutionary processes governing technology change are subject …
Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood
Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood
IGC Proceedings (1977-2023)
The experiment was designed to determine the effects of land spreading of animal manures on the nutrient content of surface runoff water and infiltrating soil water. This report deals only with nitrogen (N) and attempts to quantify the losses through runoff, leaching, and volatilization of ammonia (NH3) as well as N uptake in the grass over a 3-year period. Experimental plots sited on grassland, on two soil types (a moderately drained loam and an impermeable gley), were equipped to collect surface runoff water. Ceramic probes were installed in each plot at 15-, 30-, 60-, and 100-cm depths to extract infiltrating …
Annual Losses Of Ammonia From A Grazed Pasture Fertilized With Urea, V R. Catchpoole, L A. Harper, R J.K Keyers
Annual Losses Of Ammonia From A Grazed Pasture Fertilized With Urea, V R. Catchpoole, L A. Harper, R J.K Keyers
IGC Proceedings (1977-2023)
Nitrogen-balance studies have shown losses of applied nitrogen (N) from grazed pastures in southeastern Queensland. Losses as high as 80% have been observed from urea N broadcast at 376 kg N/ha/yr over 8 years on a Setaria sp1uu:elata cv. Nandi pasture. Management techniques aimed at reducing this loss and thereby increasing the efficiency of use of N by pastures cannot be devised until the pathways of loss are known. The objective of this research was to estimate the annual ammonia (NH3) loss by convective transport from a urea-fertilized pasture at Samford Pasture Research Station in southeastern Queensland. Urea was broadcast …
Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney
Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney
IGC Proceedings (1977-2023)
Grazing ruminants aggregate large quantities of forage nitrogen (N) into urine patches. Pasture plots treated with urine N were studied to assess its fate under contrasting seasonal conditions: cool-moist (representing winter-spring); warm-moist (late spring-early summer), and warm-dry (late summer-autumn). A permanent ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) sward on free-draining alluvial soil was studied. 'freatments were replicated in randomized blocks. Urine N was applied at 30 or 60 g N/m2• Relevant measurements were then continued until treatment differences disappeared. Apparent N balances for urine treatments were compiled. Fixation by white clover was always greatly reduced in …
Effects Of Grazing Management On Seasonal Variation In Nitrogen Fixation, J L. Brock, J H. Hoglund, R H. Fletcher
Effects Of Grazing Management On Seasonal Variation In Nitrogen Fixation, J L. Brock, J H. Hoglund, R H. Fletcher
IGC Proceedings (1977-2023)
Using the acetylene reduction assay, field studies in recent years have investigated the variation in N fixation in grazed systems, and some of the principles involved in the interaction with available soil N have been described. This experiment extends this work to include the effect of grazing management on the factors influencing N fixation. Two self-contained sheep-grazed units, one a 10-paddock rotationally grazed system and the other set stocked, were established on a high-fertility ryegrass-white clover pasture, with a basic stocking rate of 22 sheep/ha. Over the 1975-1978 period, both units were monitored for pasture growth, N fixation, and associated …
Symbiotic Nitrogen Fixation Of Alfalfa, Birdsfoot Trefoil, And Red Clover, G H. Heichel, C P. Vance, D K. Barnes
Symbiotic Nitrogen Fixation Of Alfalfa, Birdsfoot Trefoil, And Red Clover, G H. Heichel, C P. Vance, D K. Barnes
IGC Proceedings (1977-2023)
Forage legumes such as alfalfa (Medicago sativa L.), birdsfoot trefoil (Lotus comiculatus L.), and red clover (Trifolium pratense L.), grown in crop rotations, can provide an inexpensive source of nitrogen (N) to succeeding crops. Few quantitative measurements of seasonal patterns of N fixation in managed communities of perennial forage legumes have been undertaken, chiefly because of the lack of satisfactory methods. Therefore, there is little knowledge of how N fixation varies with crop development, yielding ability, and weather patterns. Quantitative measurements of N fixation are important in choosing the appropriate legume for use in a crop rotation and for …
Photosynthate Supply And Nitrogen Fixation In Forage Legumes, P M. Murphy
Photosynthate Supply And Nitrogen Fixation In Forage Legumes, P M. Murphy
IGC Proceedings (1977-2023)
Photosynthate supply is known to limit nitrogen fixation in legumes, and the resulting shortfall in energy supply necessary for maximum crop production may be aggravated by the energy-wasteful process of hydrogen (H2) evolution by the legume N2 fixing system. There is less information available on these aspects of the nitrogen-fixing process in forage legumes, such as white clover (Trifolium repens). The objectives of the present work were to determine how N2(C2H2) fixation and H2 production are influenced by carbohydrate supply in forage legumes.
Plants were grown under controlled environmental conditions, and nodule energy supply was varied by adjusting …
Selection Of Rhizobium Strains For Enhanced Dinitrogen Fixation In Forage Legume Production, C Hagedorn, W E. Knight
Selection Of Rhizobium Strains For Enhanced Dinitrogen Fixation In Forage Legume Production, C Hagedorn, W E. Knight
IGC Proceedings (1977-2023)
A set of procedures for the selection of Rhizobium strains for enhanced dinitrogen fixation in forage legumes is presented. Although forage legumes are among the most efficient members of the Leguminosae regarding biological nitrogen fixation (BNF), they are generally neither productive nor persistent without effective nodulation by appropriate rhizobia. The following methods define a selection and evaluation process to obtain appropriate Rhizobium strains. These include (1) regional survey of the production area, (2) strain collection and soil analyses, (3) strain characterization, (4) strain selection and manipulation, and (5) field evaluation of strains. The initial procedure is to survey the region …
Interactions Between Grasses And Rhizosphere Nitrogen-Fixing Bacteria, M H. Gaskins, D H. Hubbell, S L. Albrecht
Interactions Between Grasses And Rhizosphere Nitrogen-Fixing Bacteria, M H. Gaskins, D H. Hubbell, S L. Albrecht
IGC Proceedings (1977-2023)
Sorghum and Digitaria cultivars grown in soil or nutrient solutions were inoculated with a strain of Azospirillum in short-term greenhouse experiments. Carbon compounds lost by roots in solution culture experiments were determined in order to estimate the quantity of energy substrates that might be obtained by rhizosphere organisms from growing plants. Other plants were treated with plant growth hormones, and responses were compared to those of plants treated with killed Azospirillum cells. The similarity of the responses suggests that growth-hormone production by the inoculant organism, rather than nitrogen (N) fixation, is responsible for part or all of the increase in …
Simple Computer Simulation Models For Forage-Management Applications, G W. Fick, D Onstad
Simple Computer Simulation Models For Forage-Management Applications, G W. Fick, D Onstad
IGC Proceedings (1977-2023)
Dynamic computer simulation models of forage growth can be useful in interpreting physical and biological limitations on production and in designing management systems for testing in the field. The explanatory detail of such models makes them both more reliable and more expensive to use than simple empirical formulations. Simple simulation models reduce the expense. They can also serve as reference points for designing, evaluating, or selecting more complex versions and thus provide a more rational basis for using models in grassland research and management. Our objectives were to develop and to test a simple dynamic simulation model of alfalfa (Medicago …
Energy Flow And Conversion Efficiency In Grazing Grassland, T Akiyama, S Takahashi, M Shiyomi, T Okubo
Energy Flow And Conversion Efficiency In Grazing Grassland, T Akiyama, S Takahashi, M Shiyomi, T Okubo
IGC Proceedings (1977-2023)
Measurable energy storage on grassland ecosystems was examined for 5 years at the Fujinita site under the same rotation program with two grazing intensities. Daily global solar radiation and photosynthetic active radiation were measured as the energy sources in the ecosystem. Primary production by pasture plants and amount grazed by cattle were estimated by the biomass differences inside and outside of protection cages. For the estimation of energy produced or stored by plants or cattle, calorific values were examined for dominant plant species at the Fujinita site. Seasonal changes in digestibility were investigated to ascertain the energy of herbage digested …
A System Approach To Swedish Ley Production, J F. Angus, A Kornher, B.W R. Torssell
A System Approach To Swedish Ley Production, J F. Angus, A Kornher, B.W R. Torssell
IGC Proceedings (1977-2023)
A simulation model for estimating yield of leys from standard meteorological observations is described. It is based on an S-shaped growth curve also accounting for phasic development and regrowth depression. Effects of temperature, radiation, and soil moisture are accounted for by a growth index. Soil moisture is simulated with a standard water budget. The parameters in the model were estimated by comparing measured with calculated growth. The model then predicted final harvest with reasonable accuracy, but with underestimate of early season growth, presumably due to mobilization of carbohydrate from storage organs. Observed ley yields from 49 Swedish parishes (1961-1978) were …