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The Role Of Dietary Highly Unsaturated N-3 Fatty Acids In Northern Quahogs, Mercenaria Mercenaria, Through Decreasing Temperature, Sixto E. Portilla 2017 The Graduate Center, City University of New York

The Role Of Dietary Highly Unsaturated N-3 Fatty Acids In Northern Quahogs, Mercenaria Mercenaria, Through Decreasing Temperature, Sixto E. Portilla

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

The series of investigations described in this thesis were designed to assess the effect of diet on mortality through decreasing temperature in two genetic varieties of M. mercenaria important to the natural environment and the aquaculture industry: “wild” from natural stocks and “notata” selected for fast growth. Data from these novel investigations demonstrate a temperature specific sensitivity to each dietary component designating 20:5n-3 as homeoviscously favorable in the upper thermal range above 12°C, and 22:6n-3 as favorable in the lower. Statistical analyses of variance demonstrate distinct cumulative mortalities among the 5 dietary treatments (P < 0.05) for each genetic variety at each thermal range, upper (>12°C) and ...


Ancient Bacteria–Amoeba Relationships And Pathogenic Animal Bacteria, Joan E. Strassmann, Longfei Shu 2017 Washington University in St Louis

Ancient Bacteria–Amoeba Relationships And Pathogenic Animal Bacteria, Joan E. Strassmann, Longfei Shu

Biology Faculty Publications & Presentations

Long before bacteria infected humans, they infected amoebas, which remain a potentially important reservoir for human disease. Diverse soil amoebas including Dictyostelium and Acanthamoeba can host intracellular bacteria. Though the internal environment of free-living amoebas is similar in many ways to that of mammalian macrophages, they differ in a number of important ways, including temperature. A new study in PLOS Biology by Taylor-Mulneix et al. demonstrates that Bordetella bronchiseptica has two different gene suites that are activated depending on whether the bacterium finds itself in a hot mammalian or cool amoeba host environment. This study specifically shows that B. bronchiseptica ...


Burkholderia Cenocepacia J2315-Mediated Destruction Of Staphylococcus Aureus Nrs77 Biofilms., Rachel Thompson 2017 University of Louisville

Burkholderia Cenocepacia J2315-Mediated Destruction Of Staphylococcus Aureus Nrs77 Biofilms., Rachel Thompson

College of Arts & Sciences Senior Honors Theses

Cystic fibrosis (CF) is an inherited disorder that affects over 30,000 people in the US and more than 70,000 people worldwide. Recurring bacterial infections in CF patients result in tissue damage that dramatically lowers respiratory function and are ultimately fatal. The formation of bacterial biofilms in the mucus and on lung epithelial tissue allows pathogens to be protected from antibiotics and the host immune system, making treatment of infection difficult. The interactions between CF pathogens in co-culture biofilms are not well understood and were examined in this study. Staphylococcus aureus and Burkholderia cenocepacia, two common CF pathogens, were ...


Measuring Soil Electrical Conductivity To Delineate Zones Of Variability In Production Fields, Gretchen Sassenrath, S. Kulesza 2017 Kansas State University

Measuring Soil Electrical Conductivity To Delineate Zones Of Variability In Production Fields, Gretchen Sassenrath, S. Kulesza

Kansas Agricultural Experiment Station Research Reports

Production fields in southeast Kansas are highly variable. Differences in elevation and changes in soil texture contribute to unevenness in plant-available moisture and nutrients, resulting in significant inconsistencies in crop production and yield within a field. These variabilities complicate management and impact the return on investments from different areas of the field. Identification of the regions of variability is possible through several methods, including visual inspection, remote imagery, and yield maps. An additional method of assessing soil variability is by measuring the electrical conductivity of the soil. Measuring apparent electrical conductivity gives a map of the spatial distribution of soil ...


Key Components Of Healthy Soils And Their Role In Crop Production, C. J. Hsiao, Gretchen Sassenrath, Charles Rice, L. Zeglin, G. Hettiarachchi 2017 Kansas State University

Key Components Of Healthy Soils And Their Role In Crop Production, C. J. Hsiao, Gretchen Sassenrath, Charles Rice, L. Zeglin, G. Hettiarachchi

Kansas Agricultural Experiment Station Research Reports

Soil health is a confusing term that means different things to different people. To a crop producer, healthy soils are critical for good crop growth and yield. Some soil properties include soil texture, such as the relative percentage of sand, silt and clay; the water content; nutrient levels; organic carbon content; the microbial community; and microbial activity. These properties are determinants of soil health. Our research confirmed that changes in soil management affect the composition and activity of soil microorganisms in surface soils. Greater concentrations of microbial biomass and arbuscular mycorrhizal fungus (AMF) in the no-till agricultural system indicated healthier ...


Impact Of Cations On The Sorption Capabilities Of Kaolin Towards Biofilm-Forming Bacteria, Rachel E. Brineman 2017 Georgia College and State University

Impact Of Cations On The Sorption Capabilities Of Kaolin Towards Biofilm-Forming Bacteria, Rachel E. Brineman

Georgia College Student Research Events

Biofilm-forming bacteria cause problems for industries such as medical, food, and water treatment. Due to its heterogeneous charges, kaolin is capable of sorption of these microorganisms. These charges are impacted by pH and cations, which change the electrostatic interactions between kaolin particles and microorganisms. Proper pH and cation composition may lead to enhanced sorption. The impact of Al3+ cations on kaolin sorption of Gram negative (E. coli and P. aeruginosa) and Gram positive (B. megaterium and S. aureus) was investigated. Calcined kaolin and Diatomaceous Earth kaolin, which were selected in previous studies, were incubated in triplicates with the above organisms ...


In Vitro Studies On Metabolism Of Salvinorin A, Lukasz M. Kutrzeba, Vardan T. Karamyan, Robert C. Speth, John S. Williamson, Jordan K. Zjawiony 2017 University of Mississippi

In Vitro Studies On Metabolism Of Salvinorin A, Lukasz M. Kutrzeba, Vardan T. Karamyan, Robert C. Speth, John S. Williamson, Jordan K. Zjawiony

John Williamson

Microbial transformation of natural products is a well established model for mammalian metabolism. Salvinorin A, a diterpenoid isolated from the hallucinogenic mint Salvia divinorum Epling & Játiva-M (Lamiaceae), is a potent non-nitrogenous κ-opioid receptor agonist. The metabolism of salvinorin A has still not yet been well established. Thirty fungal species were screened for the ability to metabolize salvinorin A. We observed that salvinorin A undergoes fast hydrolysis of the acetate group at carbon atom C2, resulting in formation of the pharmacologically inactive product, salvinorin B. Ex vivo experiments were also performed using organelle fractions isolated from rat liver and brain. Crude ...


Microflora In The Cheek Pouches Of Ord's Kangaroo Rat (Dipodomys Ordii) From The Nebraska Sandhills, Devin M. Christensen 2017 University of Nebraksa Omaha

Microflora In The Cheek Pouches Of Ord's Kangaroo Rat (Dipodomys Ordii) From The Nebraska Sandhills, Devin M. Christensen

Student Research and Creative Activity Fair

The microflora living within the Ord’s kangaroo rat (Dipodymis ordii) cheek pouches has never been extensively studied before. Kangaroo rats use their cheek pouches to transport seeds and grasses in their mouths that they later store. It is predicted that the cheek pouches harbor fungal and bacterial growth that could be either helpful or harmful to the kangaroo rat and its environment. 8 kangaroo rats were humanely captured using Sherman live traps in the Nebraska Sandhills; their cheek pouches were swabbed, and the microorganisms obtained were grown on agar plates and in liquid media until an adequate amount of ...


Relating Watershed Characteristics To Elevated Stream Escherichia Coli Levels In Agriculturally Dominated Landscapes: An Iowa Case Study, Conrad Brendel, Michelle L. Soupir 2017 Iowa State University

Relating Watershed Characteristics To Elevated Stream Escherichia Coli Levels In Agriculturally Dominated Landscapes: An Iowa Case Study, Conrad Brendel, Michelle L. Soupir

Agricultural and Biosystems Engineering Publications

Fecal Indicator Bacteria (FIB) such as Escherichia coli (E. coli) are a leading cause of surface water impairments in the United States. However, the relative impacts of different watershed characteristics on microbial water quality in agriculturally dominated watersheds are unclear. Spatial and statistical analyses were utilized to examine relationships between watershed characteristics and FIB and a multiple regression model was created. Geometric mean E. coli concentration data were obtained for 395 ambient water quality monitoring locations in Iowa. Watersheds were delineated for thirty randomly selected monitoring locations and drainage areas ranged from 93 to 1.1 million hectares. Watershed characteristics ...


Diversity And Biocide Susceptibility Of Fungal Assemblages Dwelling In The Art Gallery Of Magura Cave, Bulgaria, Milena M. Mitova, Mihail Iliev, Alena Novakova, Anna A. Gorbushina, Veneta I. Groudeva, Pedro M. Martin-Sanchez 2017 Sofia University

Diversity And Biocide Susceptibility Of Fungal Assemblages Dwelling In The Art Gallery Of Magura Cave, Bulgaria, Milena M. Mitova, Mihail Iliev, Alena Novakova, Anna A. Gorbushina, Veneta I. Groudeva, Pedro M. Martin-Sanchez

International Journal of Speleology

Magura Cave, north-western Bulgaria, possesses valuable rock-art paintings made with bat guano and dated from the period between the Eneolithic and Bronze Ages. Since 2008, the Art Gallery is closed to the general public in order to protect the paintings from vandalism, microclimatic changes caused by visitors and artificial illumination, and the consequent growth of fungi and phototrophs. Nevertheless, some tourist visits are allowed under the supervision of cave managers. This study provides the first scientific report on cultivable fungal assemblages dwelling different substrata in the Art Gallery. A total of 78 strains, belonging to 37 OTUs (Ascomycota 81%, Zygomycota ...


Microbial Repopulation Following In Situ Star Remediation, Gavin Overbeeke 2017 The University of Western Ontario

Microbial Repopulation Following In Situ Star Remediation, Gavin Overbeeke

Electronic Thesis and Dissertation Repository

In situ STAR (Self-sustaining Treatment for Active Remediation) is an emerging remediation technology which uses smouldering combustion to destroy nonaqueous phase liquid (NAPL) contamination in the subsurface. Since STAR smouldering travels through contaminated soils slowly (~0.5 to 5 m/day) and subjects them to high temperatures (400–1000°C), it is expected that this technology will thoroughly dry and sterilize the zones which it treats. Further, soils surrounding the treatment zone which are not smouldered will be heated, although not smouldered, by virtue of their proximity to STAR, impacting microbial communities within them. Therefore, the objectives of this work ...


Beyond The Obvious: Emerging Contaminants And Biogeochemistry As A Cause And Solution For Nitrogen Pollution, Stephanie L. DeVries 2017 The Graduate Center, City University of New York

Beyond The Obvious: Emerging Contaminants And Biogeochemistry As A Cause And Solution For Nitrogen Pollution, Stephanie L. Devries

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

Following a comprehensive review of the occurrence and impacts of antibiotics and related pharmaceutical compounds on the terrestrial N-cycle, three experiments were performed to explore the topic of biogeochemistry as a source or a sink for N-pollution. The first of these experiments addresses the question of whether environmentally relevant concentrations of antibiotics (µg·kg-1) have a significant effect on denitrification or N2O production, a question that has not been well addressed in previous studies. Having determined that there is a significant shift, the second study aims to comprehensively follow changes to soil N pools and N2 ...


Freshwater Fungal Infections, Dennis J. Baumgardner 2017 Aurora UW Medical Group, Aurora Health Care

Freshwater Fungal Infections, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or fails ...


The Effects Of Polyunsaturated Aldehydes On Pelagic Microbial Food Webs In The Chesapeake Bay Area And Atlantic Coastal Waters, Chase Alfman 2017 The University of Akron

The Effects Of Polyunsaturated Aldehydes On Pelagic Microbial Food Webs In The Chesapeake Bay Area And Atlantic Coastal Waters, Chase Alfman

Honors Research Projects

Diatoms, one of the most common classes of phytoplankton, are autotrophic plankton, and are the primary food source for many organisms. Diatoms play a key role in nearly all oceanic food webs. Under stressful conditions, diatoms can undergo biological changes that produce cytotoxic secondary metabolites such as polyunsaturated aldehydes (PUA’s). This process is a form of allelopathy, utilized by many algae as a defense mechanism against predation, as well as to inhibit competitors. Microzooplankton are an essential part of these aquatic food webs as well, as they are a key herbivore in many oceanic environments. A set of experiments ...


Analysis Of Microbial Diversity In Disturbed Soil, Tyler G. Sanda 2017 University of Akron

Analysis Of Microbial Diversity In Disturbed Soil, Tyler G. Sanda

Honors Research Projects

This paper uses the composition and abundance of microbial species to analyze soil recovery in disturbed land. Surface mining disturbs ecological communities throughout the world. As organizations seek to reclaim these disturbed lands, a proper analysis of recovery is needed. In previous studies, recovery of disturbed land was limited to surface examinations, which do not characterize the possible unseen devastating effects of the subsoil. Soil microorganisms are extremely sensitive to environmental changes such as strip mining. It is proposed that these microorganisms may serve as better indicators of recovery post disturbance. Our analysis indicates microbial recovery, however it may not ...


A Survey Of Β-Lactam Antibiotic Resistance Genes And Culturable Ampicillin Resistant Bacteria In Minnesota Soils, Emily M. Wollmuth 2017 Hamline University

A Survey Of Β-Lactam Antibiotic Resistance Genes And Culturable Ampicillin Resistant Bacteria In Minnesota Soils, Emily M. Wollmuth

Departmental Honors Projects

Since the discovery of penicillin, antibiotics have been an essential tool in the treatment of bacterial infections and diseases. It is estimated that antibiotics and antibiotic resistance genes have existed for billions of years. With the increasing appearance of resistant pathogenic bacteria, there has been growing concern. β-lactam antibiotics make up the largest portion of the global market, so resistance to these antibiotics is especially alarming. It has been theorized that frequency and type of antibiotic resistance genes vary by area. Previous studies suggest that these differences may be related to antibiotic use in agricultural and urban areas. To survey ...


Antibiotic Resistance Genes In Minnesota Soil Bacteria From Areas Of High And Low Ferric Iron, GUNNER L. DROSSEL, Presley Martin PhD 2017 Hamline University

Antibiotic Resistance Genes In Minnesota Soil Bacteria From Areas Of High And Low Ferric Iron, Gunner L. Drossel, Presley Martin Phd

Departmental Honors Projects

Naturally-occurring antibiotic resistance genes in soil bacteria represent a potentially important reservoir of genes that could contribute to antibiotic resistance of human pathogens. It has been reported that over 40 genes in bacterial genomes are controlled by concentrations of ferric iron. We examined the effect of soil metal content on the level of resistance to two antibiotics, ampicillin (Amp) and tetracycline (Tet), and the presence of multiple genes that code for efflux pump-mediated resistance. These pumps act to export toxins (e.g. heavy metals and antibiotics, perhaps). Because of this, growth in heavy metal-contaminated soils might select for antibiotic resistance ...


Short-Term Wildfire Impacts In A Rocky Mountain Catchment: Searching For Evidence Of Riverine Black Carbon Transport After The Cold Springs Wildfire, Dillon McClintock Ragar 2017 University of Colorado, Boulder

Short-Term Wildfire Impacts In A Rocky Mountain Catchment: Searching For Evidence Of Riverine Black Carbon Transport After The Cold Springs Wildfire, Dillon Mcclintock Ragar

Undergraduate Honors Theses

Black Carbon (BC) is a long-lasting and ubiquitous product of combustion. It is found nearly everywhere on the Earth’s surface, oceans, and atmosphere. It was originally considered to be very stable in soils, but is now understood to be mobile in terrestrial and aquatic environments. The magnitude of BC flux into oceans via riverine transport has been established, but the exact conditions under which transport occurs are unknown. This research monitored surface water sites to determine if a pulse of BC could be identified from a recently burned forested area in the Colorado Rocky Mountains. BC was shown to ...


Effects Of Fertilizer And Shade Management On Nitrogen Mineralization, Nitrifying Microbial Abundance And Nitrogen-Fixing Capacity Of Erythrina Poeppigiana In Coffee (Coffea Arabica) Agroforestry Systems In Costa Rica, Stuart E. Barker III 2017 Georgia Southern University

Effects Of Fertilizer And Shade Management On Nitrogen Mineralization, Nitrifying Microbial Abundance And Nitrogen-Fixing Capacity Of Erythrina Poeppigiana In Coffee (Coffea Arabica) Agroforestry Systems In Costa Rica, Stuart E. Barker Iii

Electronic Theses & Dissertations

Worldwide chemical fertilizer use has increased by four times during the last 50 years. Conventional agricultural systems have a high nitrifying nature, resulting in a loss of nearly 70% of overall nitrogen (N) fertilizer inputs, an estimated economic loss of $81 billion. Over application of fertilizer is rampant in tropical developing nations in Central America, where coffee is major crop. Agroforestry offers ecologically sustainable land management strategies that promote the provision of ecosystem services such as, protection of biodiversity, climate change mitigation, and water and soil regulation. When legume trees are incorporated as the shade tree in coffee production, direct ...


The Influence Of The Invasive Chinese Tallow (Triadica Sebifera) Leaf Litter On Aquatic Chemistry And Microbial Community Composition, Raymond D. Montez 2016 Stephen F Austin State University

The Influence Of The Invasive Chinese Tallow (Triadica Sebifera) Leaf Litter On Aquatic Chemistry And Microbial Community Composition, Raymond D. Montez

Electronic Theses and Dissertations

Global climate change and anthropogenic activity have facilitated the movement and invasive potential of nonnative plants in native environments. These invasions can have negative effects on ecosystem diversity and function. The nonnative and invasive plant, Chinese Tallow (Triadica sebifera), has already invaded much of the south eastern US where it is outcompeting native tree species and changing ecosystem diversity in a variety of habitats. Leaf litter from the Chinese tallow has been shown cause changes in dissolved oxygen and pH in the aquatic environment. Turbidity is also affected when Chinese tallow litter is present in water. A series of experiments ...


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