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Full-Text Articles in Entire DC Network
Shrimp Farming In Thailand: A Pathway To Sustainability, Warinyupa Phornprapha
Shrimp Farming In Thailand: A Pathway To Sustainability, Warinyupa Phornprapha
Pomona Senior Theses
Throughout this thesis I have laid out several factors that have contributed to the sustainability of shrimp farming in Thailand, and if sustainability whilst maintaining production can ever be achieved. To find out the current situation of shrimp farming in Thailand, the history of global and Thai shrimp farming is described. The social and environmental problems of the unsustainable history of shrimp farming in Thailand is then considered. Solutions to these effects conclude that it is up to the consumer to demand for better regulations from the government and the shrimp companies to ensure a sustainable future for shrimp farming …
Estimates Of Calf Survival And Factors Influencing Roosevelt Elk Mortality In Northwestern California, Erin Nigon
Estimates Of Calf Survival And Factors Influencing Roosevelt Elk Mortality In Northwestern California, Erin Nigon
Cal Poly Humboldt theses and projects
Survival of juvenile ungulates is known to be highly variable, yet it is fundamental to understanding the dynamics and trends of wildlife populations. Factors influencing calf survival are poorly understood in northwestern California where Roosevelt elk (Cervus canadensis roosevelti) are known to exist. The objectives of this study were 1) to estimate summer and annual survival rates and determine recruitment rates for Roosevelt elk calves in the area, 2) to evaluate differences in calf survival by examining the effects of individual and population level covariates on summer and annual calf survival, 3) to identify factors influencing the timing …
Borehole Water And Sachet Water Production In Southeast Nigeria, Joseph Emerenini
Borehole Water And Sachet Water Production In Southeast Nigeria, Joseph Emerenini
Walden Dissertations and Doctoral Studies
AbstractDrinking water is potable and safe if it is free from physical, chemical, and microbiological contaminants. Despite the Nigerian government's interventions to alleviate water contamination, a considerable number of Nigerians are still without safe potable water. The purpose of this quantitative cross-sectional study was to examine whether the level of contamination of drinking water sourced from boreholes and sachet packaged water in Owerri City, Southeast Nigeria was in compliance with World Health Organization (WHO) standards, and to examine the relationship between the physical, chemical, and bacteriological parameters of drinking water sourced from borehole and sachet packaged water The conceptual framework …
Torrefaction Of Cassava Rhizome For Catalytic Gasification Process With Mcm-41 Synthesis By Illite Waste, Punchaluck Sirinwaranon
Torrefaction Of Cassava Rhizome For Catalytic Gasification Process With Mcm-41 Synthesis By Illite Waste, Punchaluck Sirinwaranon
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the cassava rhizome (CR) was torrefied under different atmosphere to produce a superior green solid fuel for subsequent catalytic gasification. The research consists of 3 parts. The first part was to study the effect of torrefaction temperature (220–300°C) under nitrogen (N2) and simulated flue gas (SFG) at a residence time of 30 and 60 minutes. The highest carbon content in obtained solid fuel ranged from 51.45–65.09%, meanwhile the lowest oxygen content was 19.36% at a temperature over 260˚C. The decrease of O/C ratio benefited from the fuel characteristics improvement of torrefied CR. The higher heating value of …
The Effects Of Street Tree Site Planting Width On Canopy Width And Ability To Provide Ecosystem Services, Ryan Kendall
The Effects Of Street Tree Site Planting Width On Canopy Width And Ability To Provide Ecosystem Services, Ryan Kendall
Department of Environmental Studies: Undergraduate Student Theses
In a time where pests such as emerald ash borer are reducing urban forests, it is important to gain a return on investment for new trees planted. Since trees cost money, the value of the ecosystem services that they provide over the course of their lives should outweigh their costs. Due to the need for a return on investment, it is important to know whether newly planted street trees are being planted in a space that does not inhibit their growth or ability to provide benefits. This study, in Lincoln, NE looks to determine the relationship between a street tree’s …
Advancing Quantitative Understanding Of Escherichia Coli Concentrations In A Contemporary Mixed Land-Use Watershed, In West Virginia, Usa, Fritz Petersen
Advancing Quantitative Understanding Of Escherichia Coli Concentrations In A Contemporary Mixed Land-Use Watershed, In West Virginia, Usa, Fritz Petersen
Graduate Theses, Dissertations, and Problem Reports (ETD)
A scarcity of field-based research investigating the relationships between E. coli (fecal matter) concentration, suspended particulate matter (SPM; including size distribution), physicochemical parameters (water temperature, pH, SPC, DO, chloride) and land use practices and the importance of these relationships, particularly for human health, policy makers, and water resource managers, provided the impetus for this research. A 22-site, nested-scale, experimental watershed study design was implemented to investigate E. coli concentrations and the aforementioned relationships in a contemporary mixed land use watershed in the Appalachian region of the eastern United States. Results from a reduced (n=4 sites) study showed SPM in the …
Partitioning Variation In Vegetation And Landscape Functionality In Arid Land Piosphere, Eahsan Shahriary
Partitioning Variation In Vegetation And Landscape Functionality In Arid Land Piosphere, Eahsan Shahriary
Open Access Theses & Dissertations
A piosphere is an interaction between vegetation community, watering point, and grazing livestock/wildlife. In this Dissertation, I begin by reviewing the concept of the piosphere, and the progress, knowledge gaps and common statistical approaches and errors in piosphere research. Landscape functionality, plant community distribution and their influencing factors on a piosphere in Iran are then investigated.
A total 862 piosphere publications of multiple types from 68 countries and 10 different languages during the period of 1915 â?? 2018 were reviewed. Australia was the most productive country followed by South Africa, the USA, Botswana and Argentina. Ivan Thrash is the most …
Understanding The Connections: An Analysis Of Climate Change And Human Security, Erica Martinez
Understanding The Connections: An Analysis Of Climate Change And Human Security, Erica Martinez
Open Access Theses & Dissertations
Increasing evidence shows that the impacts of anthropogenic climate change have magnified and will have dramatic implications for both the natural and social systems (Adger et al., 2014). While research on the security implications of climate change has been found to have a major bearing on policy making, experts have not reached a consensus about how climate change and human security are related, leaving the climate-security nexus and corresponding policies underdeveloped.
The purpose of this study is to delineate and scrutinize the relationship between climate change and human security so that a more comprehensive understanding of the phenomenon is achieved. …
Associations Of Traffic Related Air Pollution With Physical Activity And Cardiorespiratory Health Outcomes In At-Risk Populations From El Paso, Texas, Juan Aguilera
Open Access Theses & Dissertations
Exposure to air pollution from traffic-related emissions is a considerable preventable cause of respiratory and cardiovascular diseases. However, the impacts on at-risk populations, such as children with asthma and low-income residents, are yet to be fully understood in the border city of El Paso, TX. This dissertation focused on the most common traffic-related pollutants which include particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2), and ozone (O3). The research described in this work provides an overview of air pollution measurements and shares insights from three different studies in our region.
People with asthma are more likely adversely affected by traffic …
Life Cycle Studies To Evaluate The Physiological And Biochemical Effects Of Copper Oxide And Surface-Coated Titanium Dioxide Nanoparticles On Green Onion (Allium Fistulosum) And Carrot (Daucus Carota L.) Plants: Insights Utilizing Two-Photon Microscopy And Spectroscopy, Yi Wang
Open Access Theses & Dissertations
With the recent increase of nanomaterial production, nano copper oxide (nCuO) and surface-modified titanium dioxide nanoparticles (nTiO2) are among the most widely applied nanoparticles in industry and daily lives. Their use has resulted in accumulation in soils as a consequence of their direct or indirect release. Hence, these NPs may raise a potential risk to crops cultivated in soils. Moreover, the physiological effects of nCuO on green onion (Allium fistulosum) and surface-coated nTiO2 on full-grown carrot (Daucus carota L.) are still unknown. Green onion is characterized by its high content of the antioxidant allicin, and carrot is a worldwide economic …
Effects Of Integrated Application Of Plant-Based Compost And Urea On Soil Food Web, Soil Properties, And Yield And Quality Of A Processing Carrot Cultivar, A. Habteweld, D. Brainard, A. Kravchencko, Parwinder Grewal, H. Melakeberhan
Effects Of Integrated Application Of Plant-Based Compost And Urea On Soil Food Web, Soil Properties, And Yield And Quality Of A Processing Carrot Cultivar, A. Habteweld, D. Brainard, A. Kravchencko, Parwinder Grewal, H. Melakeberhan
School of Earth, Environmental, & Marine Sciences Faculty Publications
Soil nutrient management system characterized by reduced input of inorganic fertilizers integrated with organic amendments is one of the alternatives for reducing deleterious environmental impact of synthetic fertilizers, suppressing soil-borne pests and diseases, and improving soil health and crop yield. A hypothesis of the present study was that lower rates of urea mixed with higher rates of plant compost (PC) would improve nematode community structure, soil food web condition, soil biological, and physiochemical properties, and yield and quality of a processing carrot (Daucus carota) cultivar. Urea and PC were each applied at 135kg nitrogen (N)/ha alone or at 3:1, 1:1, …
Dissipation Of Pesticide Residues On Grapes And Strawberries Using Plasma-Activated Water, Chaitanya Sarangapani, Laurence Scally, Miroslav Gulan, P. J. Cullen
Dissipation Of Pesticide Residues On Grapes And Strawberries Using Plasma-Activated Water, Chaitanya Sarangapani, Laurence Scally, Miroslav Gulan, P. J. Cullen
Articles
In this study, we present a novel atmospheric air plasma discharge for the generation of plasma-activated water (PAW), with the aim of reducing pesticide residues on fresh fruit. For this purpose, a large discharge volume pin-to-plate cold plasma reactor was employed. The pesticide-spiked grapes and strawberries were processed with varying PAW concentrations to study their efficacies for pesticide degradation combined with an evaluation of any induced changes in key nutritional and quality attributes. The results suggest that the reduction of chlorpyrifos was 79% on grapes and 69% on strawberries while that of carbaryl was 86% on grapes and 73% on …
Research And Innovation As A Catalyst For Food System Transformation, A.C.L. Den Boer, K.P.W. Kok, M. Gill, J. Breda, Jean Cahill, C. Callenius, P. Caron, Z. Damianova, M. Gurinovic, L. Lahteenmaki, T. Lang, R. Sonnino, G. Verburg, H. Westhoek, T. Cesuroglu, B.J. Regeer, J.E.W. Broerse
Research And Innovation As A Catalyst For Food System Transformation, A.C.L. Den Boer, K.P.W. Kok, M. Gill, J. Breda, Jean Cahill, C. Callenius, P. Caron, Z. Damianova, M. Gurinovic, L. Lahteenmaki, T. Lang, R. Sonnino, G. Verburg, H. Westhoek, T. Cesuroglu, B.J. Regeer, J.E.W. Broerse
Research and Innovation - Other
Background Food systems are associated with severe and persistent problems worldwide. Governance approaches aiming to foster sustainable transformation of food systems face several challenges due to the complex nature of food systems.
Scope and approach In this commentary we argue that addressing these governance challenges requires the development and adoption of novel research and innovation (R&I) approaches that will provide evidence to inform food system transformation and will serve as catalysts for change. We first elaborate on the complexity of food systems (transformation) and stress the need to move beyond traditional linear R&I approaches to be able to respond to …
Direct And Indirect Effects Of Temperature And Prey Abundance On Bald Eagle Reproductive Dynamics, Joshua H. Schmidt, Judy Putera, Tammy L. Wilson
Direct And Indirect Effects Of Temperature And Prey Abundance On Bald Eagle Reproductive Dynamics, Joshua H. Schmidt, Judy Putera, Tammy L. Wilson
United States National Park Service: Publications
Understanding the mechanisms by which populations are regulated is critical for predicting the effects of large-scale perturbations. While discrete mortality events provide clear evidence of direct impacts, indirect pathways are more difficult to assess but may play important roles in population and ecosystem dynamics. Here, we use multi-state occupancy models to analyze a long-term dataset on nesting bald eagles in south-central Alaska with the goal of identifying both direct and indirect mechanisms influencing reproductive output in this apex predator. We found that the probabilities of both nest occupancy and success were higher in the portion of the study area where …
The Retrospective Analysis Of Radionuclides In Banded Coral From The Bikini Atoll, Athena Marie Gallardo
The Retrospective Analysis Of Radionuclides In Banded Coral From The Bikini Atoll, Athena Marie Gallardo
UNLV Theses, Dissertations, Professional Papers, and Capstones
Nuclear weapons testing conducted within the Bikini Atoll in the Marshall Islands resulted in local fallout contamination, including long lived isotopes of plutonium (Pu) and uranium (U), within the surrounding environment. The Bikini lagoon provides a continuous source of Pu (239+240Pu) and U (236U) to the Pacific Basin. The rate at which these isotopes are flushed from the lagoon to the ocean is balanced by inputs from remobilization of lagoon sediments. This research will provide a basis for predicting future change in the solubility and export potential of Pu and U in lagoon sediments. This is important to better understand …
Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell
Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell
UNLV Theses, Dissertations, Professional Papers, and Capstones
Impending threats to shrubland ecosystems, posed by climate change, necessitate niche modeling efforts to project vegetation range shifts. However, efforts often remain unguided by individual-scale interspecific plant interactions. The stress gradient hypothesis posits that facilitation should increase in areas of high abiotic stress, only if the individuals are able to ameliorate the surrounding area via functional traits. The Sheep Range of Nevada was used to assess the role of functional traits as predictors of plant association. Larrea tridentata, Coleogyne ramosissima, and Artemisia nova were selected as shrubs with variable life history strategies and ranges in order to identify general patterns …
Serological Survey And Pathogen Exposure Of Adult Female White-Tailed Deer In The Western Dakotas, Katherine L. Moratz, Bailey S. Gullikson, Eric S. Michel, Daniel M. Grove, Jonathan A. Jenks, William Jensen
Serological Survey And Pathogen Exposure Of Adult Female White-Tailed Deer In The Western Dakotas, Katherine L. Moratz, Bailey S. Gullikson, Eric S. Michel, Daniel M. Grove, Jonathan A. Jenks, William Jensen
The Prairie Naturalist
Establishing baseline values for pathogen exposure and nutritional indices is necessary to monitor population health. However, little is known about white-tailed deer (Odocoileus virginianus) pathogen exposure and nutritional condition in the Northern Great Plains. Our objective was to assess pathogen exposure and establish nutritional indices for female white-tailed deer in Dunn and Grant counties, North Dakota and Perkins County, South Dakota. During 2014, we collected blood serum from 150 adult female white-tailed deer. Pathogens with the highest antibody prevalence included West Nile Virus (WNV; 85%), epizootic hemorrhagic disease (48%), and malignant catarrhal fever (32%). Serum values for creatine …
Use Of Uav Imagery And Nutrient Analyses For Estimation Of The Spatial And Temporal Contributions Of Cattle Dung To Nutrient Cycling In Grazed Ecosystems, Amanda E. Shine
Use Of Uav Imagery And Nutrient Analyses For Estimation Of The Spatial And Temporal Contributions Of Cattle Dung To Nutrient Cycling In Grazed Ecosystems, Amanda E. Shine
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Nutrient inputs from cattle dung are crucial drivers of nutrient cycling processes in grazed ecosystems. These inputs are important both spatially and temporally and are affected by variables such as grazing strategy, water location, and the nutritional profile of forage being grazed. Past research has attempted to map dung deposition patterns in order to more accurately estimate nutrient input, but the large spatial extent of a typical pasture and the tedious nature of identifying and mapping individual dung pats has prohibited the development of a time- and cost-effective methodology. The first objective of this research was to develop and validate …
Strategies To Improve Forage Utilization By Sheep Offered Forage Mixtures, Valens Niyigena
Strategies To Improve Forage Utilization By Sheep Offered Forage Mixtures, Valens Niyigena
Graduate Theses and Dissertations
In the first experiment, alfalfa and novel endophyte-infected tall fescue (NE+) forages were harvested after a killing frost, then mixed to formulate 4 different treatments; alfalfa alone, 67% alfalfa +33% fescue, 33% alfalfa + 67% fescue, or 100% fescue. After 3 months of storage as silage, Dorper ewe lambs (n = 20; mean BW = 34.7 ± 6.65 kg) were fed silage for ad libitum consumption, using 5 animals per treatment. Increasing the proportion of NE+ tall fescue improved (P < 0.05) silage total acids and lactic acid concentrations and decreased silage ammonia concentration. Digestible dry matter and organic matter intake and nitrogen utilization parameters decreased with increasing inclusion of NE+ in diet. In the second experiment, 16 Dorper ewe lambs (41.8 ± 4.61 kg BW) were assigned to 4 different treatments; alfalfa silage alone (0 g/kg; CONT) or alfalfa silage mixed with chopped sericea lespedeza (SL) hay to provide 90 (LOW), 180 (MED), or 270 g/kg SL (HIGH) on a dry matter basis in a randomized complete block design experiment with 2 period to provide 4 observations per treatment for each experimental period. Increasing the proportion of sericea lespedeza in the diet decreased dry matter and organic matter digestibility but did not affect feed intake. Fecal nitrogen (g/kg N intake) increased linearly (P < 0.01) while urinary N (g/ day and g/ kg of N intake) tended to decreased linearly and quadratically (P ≤ 0.1) with increasing the proportion of SL in diet. In the third experiments, 16 gestating Dorper ewe lambs (49.1 ± 4.61 kg BW) were allocated to 4 treatments; alfalfa silage alone (0% g/kg; CONT) or alfalfa silage mixed with lablab purpureus(LP) hay to provide 90 (LOW), 180 (MED), or 270 g/kg LP (HIGH) on a dry matter (DM) basis, in a randomized complete block design experiment with a total 8 replication per treatment. Supplementation of LP in diet increased quadratically (P ≤ 0.04) forage dry matter, organic matter intake, digestible dry matter and digestible organic matter intake (P < 0.05). Nitrogen apparently absorbed and urinary N both decreased linearly (P < 0.01) with adding more LP hay in diet. Harvesting and mixing alfalfa and fescue after a killing frost improved silage fermentation characteristics and supplementation of tannins from SL and polyphenol from LP altered N excretion.
Key words: lablab, sericea lespedeza, alfalfa silage, nitrogen, sheep.
Histological Evidence Of Annual And Lunar Reproductive Rhythms Of Atlantic Sea Urchin, Arbacia Punctulata In The Gulf Of Mexico: Changes In Nutritive Phagocytes In Relation To Gametogenesis, Eleazar Hernandez Ii
Histological Evidence Of Annual And Lunar Reproductive Rhythms Of Atlantic Sea Urchin, Arbacia Punctulata In The Gulf Of Mexico: Changes In Nutritive Phagocytes In Relation To Gametogenesis, Eleazar Hernandez Ii
Theses and Dissertations
Environmental phenomena such as temperature, photoperiod, tidal cycle, and lunar rhythm act as external cues that stimulate the reproductive activity of marine organisms. In this study, I report the annual and lunar reproductive cycles, and changes in nutritive phagocytes (NPs) in relation to gonadal maturation of Atlantic sea urchin (Arbacia punctulata, a primeval species). Monthly and weekly changes in gonadal development/maturation were observed histologically. In male, the testicular lobules were densely packed with sperm from June to August. In female, on the other hand, mature eggs first appeared in some ovaries in May, numerically increased from June to …
The Prairie Naturalist, Vol. 51, Issue 2, December 2019
The Prairie Naturalist, Vol. 51, Issue 2, December 2019
The Prairie Naturalist
45 EDITOR’S NOTE: Final Thoughts as Editor-in-Chief, by Christopher N. Jacques
RESEARCH ARTICLES
47 Bats of the Loess Hills Ecoregion of Southeast Nebraska, by Virgil Brack, Jr., Dale W. Sparks, and Darwin C. Brack
58 Serological Survey and Pathogen Exposure of Adult Female White-tailed Deer in the Western Dakotas, by Katherine L. Moratz, Bailey S. Gullikson, Eric S. Michel, Daniel M. Grove, Jonathan A. Jenks, and William F. Jensen
68 Factors Limting Reintroduced Plains Topminnow, Fundulus sciadicus, Populations in Central Great Plains Streams, by Joseph D. Thiessen, Keith D. Koupal, and Casey W. Schoenebeck
NOTES
77 Recent Observations of Water …
Benchmarking On-Farm Maize Nitrogen Balance In The Western U. S. Corn Belt, Fatima Amor Tenorio
Benchmarking On-Farm Maize Nitrogen Balance In The Western U. S. Corn Belt, Fatima Amor Tenorio
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
A nitrogen (N) balance, calculated as the difference between N inputs and grain-N removal, provides an estimate of the potential N losses. We used N balance with other N-related metrics (partial factor productivity for N inputs, and yield-scaled N balance), to benchmark maize yields in relation with N input use in the US Corn Belt. We first used experimental data on grain-N concentration (GNC) to assess variation in this parameter due to biophysical and management factors. Subsequently, we used N balance and N-related metrics to benchmark yields in relation with N inputs in irrigated and rainfed fields in Nebraska using …
Viability Of Wetland Crops For Use In Treatment Wetlands: Nitrogen Removal From Water And Production Of Food, Andrew Denson Corder
Viability Of Wetland Crops For Use In Treatment Wetlands: Nitrogen Removal From Water And Production Of Food, Andrew Denson Corder
Theses and Dissertations
Treatment wetlands are used to treat wastewater from a variety of sources, but their functionality depends on the macrophytes present therein. To better understand the viability of wetland macrophytes both as sources of food and as agents of nitrogen removal from wastewater, this study quantified plant growth, food production, and nitrogen removal capacity of three common wetland crops as well as three locally dominant graminoid species in a variety of relevant ecological contexts. All six plant species and a control were grown over a ten-week period in three related experiments: (1) under three moisture regimes, (2) with or without competition …
Modeling Lake Temperature Response To Climate Change In The Alaskan Arctic, Thomas Balkcom
Modeling Lake Temperature Response To Climate Change In The Alaskan Arctic, Thomas Balkcom
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
This thesis study focuses on simulating lake temperature and ice duration for four lakes at the Arctic Long-Term Ecological Research site, near the Toolik Field Station in Alaska. Model projections were driven by the representative global climate model outputs under different carbon emission scenarios. Results show that my simple lake model can reproduce historical lake temperature and ice duration observations, indicating the reliability of the model for future projections. Model projections show that JuneSeptember lake temperatures would increase by 4.3-5.8 °C from the historical period with most progressive carbon emission scenarios, but by 0.7-2.2 °C in the conservative scenarios. Results …
A Model Explaining Medusahead Invasion And Novel Targeted Grazing Approaches Of Control, Casey N. Spackman
A Model Explaining Medusahead Invasion And Novel Targeted Grazing Approaches Of Control, Casey N. Spackman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Medusahead (Taeniatherum caput-medusae (L.) Nevski) is currently one of the biggest threats to rangelands and livestock operations in the Western US. High silica concentrations in medusahead contribute to its invasiveness. I developed a model to explain how silica is involved in the invasion process, and attempted to manipulate silica to increase use of the grass by livestock. Experiments were conducted to determine: 1) whether rotational grazing on established forages of improved nutritional quality would provide supplemental nutrients to increase cattle use of medusahead; 2) evaluate intake of and preference for medusahead treated with a glyphosate herbicide at different rates …
Production Of Biscuits By Substitution With Different Ratios Of Yellow Pea Flour, Jikai Zhao, Xin Liu, Xiang Bai, Fengcheng Wang
Production Of Biscuits By Substitution With Different Ratios Of Yellow Pea Flour, Jikai Zhao, Xin Liu, Xiang Bai, Fengcheng Wang
School of Earth, Environmental, & Marine Sciences Faculty Publications
To promote the commercialization of yellow pea flour (YPF) due to its nutritional benefits. Four biscuits with different YPF ratio (10%–50%) were conducted to explore the optimal addition percentage. The effects of YPF on the rheological and baking performance of biscuits were performed. The results showed that the substitution ratio of YPF and milling methods had a critical impact on the rheological properties of dough. The dough stability decreased gradually while a softening degree increased with YPF ratio increased. In a term of biscuits, the dimensions of length (L), width (W), thickness (T) and color (L*) of biscuits reduced as …
Changes In Students’ Mental Models From Computational Modeling Of Gene Regulatory Networks, Joseph Dauer, Heather E. Bergan-Roller, Gretchen P. King, Mckenzie Kjose, Nicholas J. Galt, Tomáš Helikar
Changes In Students’ Mental Models From Computational Modeling Of Gene Regulatory Networks, Joseph Dauer, Heather E. Bergan-Roller, Gretchen P. King, Mckenzie Kjose, Nicholas J. Galt, Tomáš Helikar
School of Natural Resources: Faculty Publications
Background: Computational modeling is an increasingly common practice for disciplinary experts and therefore necessitates integration into science curricula. Computational models afford an opportunity for students to investigate the dynamics of biological systems, but there is significant gap in our knowledge of how these activities impact student knowledge of the structures, relationships, and dynamics of the system. We investigated how a computational modeling activity affected introductory biology students’ mental models of a prokaryotic gene regulatory system (lac operon) by analyzing conceptual models created before and after the activity.
Results: Students’ pre-lesson conceptual models consisted of provided, system-general structures (e.g., activator, repressor) …
Non-Invasive Methods For Measuring And Monitoring Stress Physiology In Imperiled Amphibians, Edward J. Narayan, Zachery R. Forsburg, Drew R. Davis, Caitlin R. Gabor
Non-Invasive Methods For Measuring And Monitoring Stress Physiology In Imperiled Amphibians, Edward J. Narayan, Zachery R. Forsburg, Drew R. Davis, Caitlin R. Gabor
School of Earth, Environmental, & Marine Sciences Faculty Publications
Global climate change is negatively impacting global biodiversity and ectothermic vertebrates, with amphibians being the most imperiled vertebrate taxa. Increased mean global atmospheric temperatures, high rates of habitat degradation, and exposure to infectious diseases, such as chytridiomycosis, have contributed to population declines and extinctions of rare and endangered amphibian species. Field-based monitoring of physiological endocrine traits can help determine the sub-lethal effects of environmental stressors and provide early alerts when populations are chronically stressed. Recent advances in amphibian stress endocrinology include the development and use of non-invasive methods to quantify the glucocorticoid, or stress biomarker, corticosterone. Non-invasive methods, such as …
Food Habits Of Coyotes (Canis Latrans) In The Valles Caldera National Preserve, New Mexico, Suzanne J. Gifford, Eric M. Gese, Robert R. Parmenter
Food Habits Of Coyotes (Canis Latrans) In The Valles Caldera National Preserve, New Mexico, Suzanne J. Gifford, Eric M. Gese, Robert R. Parmenter
United States Department of Agriculture Wildlife Services: Staff Publications
Wildlife managers needed to understand coyote (Canis latrans) ecology in order to develop management plans on the nascent Valles Caldera National Preserve in northern New Mexico. Managers concerned about low elk (Cervus elaphus) recruitment had observed an increase in sightings of coyotes and observations of coyote predation on elk calves. Our objective was to identify and quantify coyote diet, and assess the temporal variation in coyote diet on the Valles Caldera National Preserve, particularly as related to elk calf consumption. We examined coyote food habits using 1,385 scats analyzed monthly from May 2005 to November 2008. …
Perceptions Of The Effectiveness Of Food Policy Coalitions In Strengthening Community Food Security In The United States., Joseph G. England Iii
Perceptions Of The Effectiveness Of Food Policy Coalitions In Strengthening Community Food Security In The United States., Joseph G. England Iii
USF Tampa Graduate Theses and Dissertations
Food insecurity is experienced most acutely and addressed most innovatively at the community level to which the concept of community food security (CFS) finds purchase (Hamm and Bellows, 2003). In recognition of the many varying dynamics embedded in the CFS concept, Food Policy Coalitions have become an organizational model adapted by communities across the United States. While FPCs have grown in number considerably over the last decade, there remains a considerable lack of empirical research documenting evaluation and engagement methods, as well as strategies used to address community food security. This research, framed by the Community Coalition Action Theory, draws …