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Atp Luminescence Assay As A Bioburden Estimator Of Biomass Accumulation In Caves, Janez Mulec, Andreea Oarga-Mulec 2016 Karst Research Institute, Scientific Research Centre of the Slovenian Academy of Sciences and Arts

Atp Luminescence Assay As A Bioburden Estimator Of Biomass Accumulation In Caves, Janez Mulec, Andreea Oarga-Mulec

International Journal of Speleology

A commercially available adenosine triphosphate (ATP) detection system (Hygiena, USA), supported by cultivable microbial indicators, was used to estimate bioburden in different habitats in and outside show caves: air, water and solid surfaces. A strong positive correlation between ATP concentration expressed as Relative Light Units (RLU) and Colony-Forming-Units (CFU) was observed for swab samples from cave surfaces. In terms of ATP units, surfaces in a single cave system (Postojna Cave) varied considerably (240-1,258,800 RLU/ 20 cm2) and commonly exceeded the bioburden level of analogues on the surface (0-114,390 RLU/ 20 cm2). Cave sub-habitats were colonized ...


Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr. 2016 Buffalo State College

Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr.

Biology Theses

Invasive plants often dominate novel habitats where they did not co-evolve with local species. Several hypotheses suggest mechanisms that explain increased exotic plant success, including 'novel weapons' and 'degraded mutualisms'. Japanese knotweed (Fallopia japonica) and European buckthorn (Rhamnus cathartica) are widespread plant invaders in North America that can dominate ecosystems. The goal of this study is to test whether these impacts are more consistent with novel weapons or degraded mutualism hypotheses. I examine tree seedling recruitment, (germination and initial survival) growth, (biomass) and mycorrhizal invasion (AMF content) as a function of F. japonica and R. cathartica root exudates. Given that ...


Microbial Extracellular Enzymes In Marine Sediments: Methods Development And Potential Activities In The Baltic Sea Deep Biosphere, Jenna Marie Schmidt 2016 University of Tennessee, Knoxville

Microbial Extracellular Enzymes In Marine Sediments: Methods Development And Potential Activities In The Baltic Sea Deep Biosphere, Jenna Marie Schmidt

Masters Theses

The deep biosphere is defined as the subsurface ecosystem in which little energy is available to microorganisms and microorganisms can live for thousands of years. Heterotrophic microbes survive in the deep biosphere even though organic matter is limited and highly recalcitrant in nature. Measuring microbial extracellular enzyme activity provides a potential means to evaluate the rate at which microorganisms are performing carbon remineralization in the energy limited sediment beneath the seafloor. Extracellular enzymes breakdown organic compounds so that the nutrients can move inside the cell and be used for energy. This study explored the role extracellular enzymes play in the ...


Comparative Genomics, Transcriptomics, And Physiology Distinguish Symbiotic From Free-Living Chlorella Strains, Cristian F. Quispe, Olivia Sonderman, Maya Khasin, Wayne R. Riekhof, James Van Etten, Kenneth Nickerson 2016 University of Nebraska-Lincoln

Comparative Genomics, Transcriptomics, And Physiology Distinguish Symbiotic From Free-Living Chlorella Strains, Cristian F. Quispe, Olivia Sonderman, Maya Khasin, Wayne R. Riekhof, James Van Etten, Kenneth Nickerson

Kenneth Nickerson Papers

Most animal–microbe symbiotic interactions must be advantageous to the host and provide nutritional benefits to the endosymbiont. When the host provides nutrients, it can gain the capacity to control the interaction, promote self-growth, and increase its fitness. Chlorella-like green algae engage in symbiotic relationships with certain protozoans, a partnership that significantly impacts the physiology of both organisms. Consequently, it is often challenging to grow axenic Chlorella cultures after isolation from the host because they are nutrient fastidious and often susceptible to virus infection. We hypothesize that the establishment of a symbiotic relationship resulted in natural selection for nutritional and ...


From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, José Rodrigo Mendoza 2016 University of Nebraska-Lincoln

From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, José Rodrigo Mendoza

Dissertations & Theses in Food Science and Technology

This project aimed to implement the use of metal silos to improve quality and safety of maize consumed by inhabitants of the highlands of Guatemala. This manuscript includes a literature review of the maize production chain in Guatemala, a survey about agricultural practices used in the region of study, as well as a characterization of the analyzed maize regarding its mycoflora, nutritional composition, and insect infestation. To better understand the current situation regarding agricultural practices and maize consumption, a survey was carried out. Sample consisted of 280 families representing 14 rural communities distributed in the townships of Todos Santos and ...


Bioaugmentation And Correlating Anaerobic Digester Microbial Community To Process Function, Kaushik Venkiteshwaran 2016 Marquette University

Bioaugmentation And Correlating Anaerobic Digester Microbial Community To Process Function, Kaushik Venkiteshwaran

Dissertations (2009 -)

This dissertation describes two research projects on anaerobic digestion (AD) that investigated the relationship between microbial community structure and digester function. Both archaeal and bacterial communities were characterized using high-throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, bioaugmentation using a methanogenic, aerotolerant propionate enrichment culture was investigated as a possible method to increase digester methane production. Nine anaerobic digesters, seeded with different biomass, were operated identically and their quasi steady state function was compared. Before bioaugmentation, different seed biomass resulted in different quasi steady state function, with digesters clustering into high, medium or low ...


Microbial Biodiversity Associated With The Walnut Juglans Regia L. In South Tyrol (Italy), Ruth Pardatscher, Wolfgang Schweigkofler 2016 Research Centre for Agriculture and Forestry, Laimburg

Microbial Biodiversity Associated With The Walnut Juglans Regia L. In South Tyrol (Italy), Ruth Pardatscher, Wolfgang Schweigkofler

Wolfgang Schweigkofler

The endophytic and epiphytic microflora from walnut trees in South Tyrol (Northern Italy) was analyzed. A total of 16 trees from 8 sites were sampled at three dates during the warm season (May, July and September) in 2005, using plant material from three different tissue types (leaves, fruit and lignified twigs). Samples were either transferred directly onto nutrient medium or surface sterilized prior to plating to distinguish between epiphytic and endophytic growth. A total of 3,880 culturable isolates were obtained, the vast majority of the isolates (3,742) belonging to fungi (96.4%); only 138 (3.6%) were bacteria ...


Comparison Of Synthetic Versus Organic Herbicides/Insecticides On Arbuscular Mycorrhizal Fungi In Abelmoschus Esculentus, Ariel Freidenreich 2016 Florida International University

Comparison Of Synthetic Versus Organic Herbicides/Insecticides On Arbuscular Mycorrhizal Fungi In Abelmoschus Esculentus, Ariel Freidenreich

FIU Electronic Theses and Dissertations

Arbuscular mycorrhizal fungi (AMF) play a crucial role in improving the growth of a vast majority of plants. Past researchers have discovered that agricultural practices have a significant negative effect on the diversity of AMF. Arbuscular mycorrhizal fungi are reported to enhance plant nutrient uptake, stress tolerance, and soil aggregate formation which are key aspects of productive low-input farming. The objective of this study was to investigate the effects of four pesticides on the ability of AMF to colonize the roots of okra plants (Abelmoschus esculentus). The pesticides being tested include two synthetic chemicals (glyphosate and carbaryl) and two organic ...


Characterization Of The Marine Sponge Amphimedon Compressa Microbiome Across A Spatial Gradient, Renee Michelle Potens 2016 Nova Southeastern University

Characterization Of The Marine Sponge Amphimedon Compressa Microbiome Across A Spatial Gradient, Renee Michelle Potens

Theses and Dissertations

Diverse and ecologically important microbial communities (microbiomes) are symbiotic within marine sponges. In this study, the microbiome of Amphimedon compressa from three sample locations (Broward and Dade Counties, Southeast Florida, USA and the Southern Caribbean, Bocas del Toro, Panama) is characterized using 16S rRNA Illumina sequencing. The predominant taxa are Proteobacteria and Cyanobacteria, as expected for Low Microbial Abundance sponges, accounting for over 53% of the total microbiome community. The numbers of Operational Taxonomic Units (OTUs) decrease from Broward County (2,900) to Dade County (2,300) and then Bocas del Toro (1,200). The correlates to a decreasing north-south ...


Lignocellulose As Carbon Source Promotes Bacterial Synergism And Reduces Antagonism, Yijie Deng 2016 The University of Southern Mississippi

Lignocellulose As Carbon Source Promotes Bacterial Synergism And Reduces Antagonism, Yijie Deng

Dissertations

Lignocellulose decomposes slowly in nature because it consists of complex polymers resistant to enzymatic degradation by most organisms. Some bacteria are capable of producing cellulolytic enzymes but the way in which bacteria interact within a community to enhance degradation of the recalcitrant substrate is poorly understood. A better understanding of how bacterial interactions affect lignocellulose degradation would provide potential approaches to improve the efficiency of lignocellulose degradation for biofuel production.

To study whether bacterial interactions enhance lignocellulose degradation, I grew environmental bacterial isolates in mixed cultures and pure cultures. I found that bacterial synergism in mixed cultures was common in ...


Disease-Causing Fungi In Homes And Yards In The Midwestern United States, Dennis J. Baumgardner 2016 Aurora UW Medical Group, Aurora Health Care

Disease-Causing Fungi In Homes And Yards In The Midwestern United States, Dennis J. Baumgardner

Dennis J. Baumgardner. MD

A number of fungal pathogens that may result in a variety of human diseases are found in residential homes and yards. The growth of these microscopic fungi is often favored by particular characteristics of the dwelling and nearby outdoor environment. Evolved virulence factors or increased ability of specific fungi to grow in diverse, and sometimes harsh, microenvironments presented by the domestic environment may promote growth and pathogenesis. Infection may occur by inhalation or direct inoculation and include endemic fungi in addition to opportunistic or emerging species. Systemic or locally aggressive fungal infections are particularly likely and may be life-threatening in ...


Handwashing: A Study Of The History, Methods, And Psychology Surrounding Hand Hygiene, Daniel J. Remillard 2016 Liberty University

Handwashing: A Study Of The History, Methods, And Psychology Surrounding Hand Hygiene, Daniel J. Remillard

Senior Honors Theses

This paper covers three different areas concerning handwashing. First a review of the history of handwashing is done, going from ancient times to its introduction into modern medicine via Dr. Ignaz Semmelweis. This section gives a sobering reminder not to instantly reject data that comes in conflict with prevalent thought.

Then current medical knowledge about handwashing is examined, and the conclusion reached states that handwashing is best done with non-antibacterial soap.

Finally, a review of the psychology of handwashing shows that medical professionals often tend toward neglect if unwatched and unmotivated by an outside source. However, those suffering from obsessive ...


Environmentally Driven Orchestration Of Metabolisms By Prochlorococcus Spp., Martin James Szul 2016 University of Tennessee - Knoxville

Environmentally Driven Orchestration Of Metabolisms By Prochlorococcus Spp., Martin James Szul

Doctoral Dissertations

In the oligotrophic waters of the world’s open oceans physical factors such as pH, salinity, and temperature are generally stable. The nutrient limited conditions as well as the low environmental variability endemic to these ecosystems select for specialists that gain fitness advantages through minimalism, efficiency, and thrift. These physical characteristics are thought to reduce nutrient demand while allowing for constant metabolic activity and growth, but the mechanisms that promote these fitness advantages are currently unknown. To better understand how these physiologies improve selective fitness for the dominant phytoplankton, we observed metabolic parameters under environmental conditions typical to these waters ...


Global Worming: A Quantitative Study About Greenhouse Gas Flux In Surface Soils Facilitated By The Anecic Earthworm, Lumbricus Terrestris, Under Rising Global Temperature, Rachel Briden Frei, Jose A. Amador 2016 University of Rhode Island

Global Worming: A Quantitative Study About Greenhouse Gas Flux In Surface Soils Facilitated By The Anecic Earthworm, Lumbricus Terrestris, Under Rising Global Temperature, Rachel Briden Frei, Jose A. Amador

Senior Honors Projects

Climate change is the long-term alteration in the Earth’s average weather conditions believed to be driven by greenhouse gases (GHG): carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). These alterations are expected to cause more extreme weather events, gradually warmer global temperatures and greater amounts of precipitation. Roughly 20% of the Earth’s CO2, one-third of CH4 and two-thirds of N2O emissions, originate from soils, and earthworms are known to accelerate GHG. As climate change proceeds, there is expected to be an increase in global temperature of 2-6ºC. Temperature is ...


Isolation And Characterization Of Microbial Communities From Hydraulic Fracturing Fluids, Sheridan S. Brewer 6284984 2016 University of Tennessee, Knoxville

Isolation And Characterization Of Microbial Communities From Hydraulic Fracturing Fluids, Sheridan S. Brewer 6284984

University of Tennessee Honors Thesis Projects

No abstract provided.


Can The Presence And Proportion Of Bacterial Communities Be Used To Estimate Post-Mortem Interval? A Critical Analysis, Alexa L. Golemo 2016 Iowa State University

Can The Presence And Proportion Of Bacterial Communities Be Used To Estimate Post-Mortem Interval? A Critical Analysis, Alexa L. Golemo

Iowa State University Anthropology Symposium

The use of bacterial communities to estimate post-mortem interval is a relatively new concept in the field of forensic anthropology, but one that shows great promise. Research has shown a correlation between the presence and proportion of bacterial communities within the microbiome of a deceased vertebrate and the post-mortem interval of that individual. Methodologies include analyzing and comparing relative abundance of different taxa during decomposition, as well as comparing the microbiome of the decomposing vertebrate to the surrounding soil during different phases of decomposition in skeletonized remains. However, this method of estimating time since death must undergo much more in-depth ...


Nutrient Limitation In Three Lowland Tropical Forests In Southern China Receiving High Nitrogen Deposition: Insights From Fine Root Responses To Nutrient Additions, Feifei Zhu, Muneoki Yoh, Frank S. Gilliam, Xiankai Lu, Jiangming Mo 2016 Marshall University

Nutrient Limitation In Three Lowland Tropical Forests In Southern China Receiving High Nitrogen Deposition: Insights From Fine Root Responses To Nutrient Additions, Feifei Zhu, Muneoki Yoh, Frank S. Gilliam, Xiankai Lu, Jiangming Mo

Frank S. Gilliam

Elevated nitrogen (N) deposition to tropical forests may accelerate ecosystem phosphorus (P) limitation. This study examined responses of fine root biomass, nutrient concentrations, and acid phosphatase activity (APA) of bulk soil to five years of N and P additions in one old-growth and two younger lowland tropical forests in southern China. The old-growth forest had higher N capital than the two younger forests from long-term N accumulation. From February 2007 to July 2012, four experimental treatments were established at the following levels: Control, N-addition (150 kg N ha–1 yr–1), P-addition (150 kg P ha–1 yr–1) and ...


Spatial Variation In Carbon And Nitrogen In Cultivated Soils In Henan Province, China: Potential Effect On Crop Yield, Xuelin Zhang, Qun Wang, Frank S. Gilliam, Yilun Wang, Feina Cha, Chaohai Li 2016 Marshall University

Spatial Variation In Carbon And Nitrogen In Cultivated Soils In Henan Province, China: Potential Effect On Crop Yield, Xuelin Zhang, Qun Wang, Frank S. Gilliam, Yilun Wang, Feina Cha, Chaohai Li

Frank S. Gilliam

Improved management of soil carbon (C) and nitrogen (N) storage in agro-ecosystems represents an important strategy for ensuring food security and sustainable agricultural development in China. Accurate estimates of the distribution of soil C and N stores and their relationship to crop yield are crucial to developing appropriate cropland management policies. The current study examined the spatial variation of soil organic C (SOC), total soil N (TSN), and associated variables in the surface layer (0–40 cm) of soils from intensive agricultural systems in 19 counties within Henan Province, China, and compared these patterns with crop yield. Mean soil C ...


Spatial Variation In Carbon And Nitrogen In Cultivated Soils In Henan Province, China: Potential Effect On Crop Yield, Xuelin Zhang, Qun Wang, Frank S. Gilliam, Yilun Wang, Feina Cha, Chaohai Li 2016 Marshall University

Spatial Variation In Carbon And Nitrogen In Cultivated Soils In Henan Province, China: Potential Effect On Crop Yield, Xuelin Zhang, Qun Wang, Frank S. Gilliam, Yilun Wang, Feina Cha, Chaohai Li

Frank S. Gilliam

Improved management of soil carbon (C) and nitrogen (N) storage in agro-ecosystems represents an important strategy for ensuring food security and sustainable agricultural development in China. Accurate estimates of the distribution of soil C and N stores and their relationship to crop yield are crucial to developing appropriate cropland management policies. The current study examined the spatial variation of soil organic C (SOC), total soil N (TSN), and associated variables in the surface layer (0–40 cm) of soils from intensive agricultural systems in 19 counties within Henan Province, China, and compared these patterns with crop yield. Mean soil C ...


Disease-Causing Fungi In Homes And Yards In The Midwestern United States, Dennis J. Baumgardner 2016 Aurora UW Medical Group, Aurora Health Care

Disease-Causing Fungi In Homes And Yards In The Midwestern United States, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

A number of fungal pathogens that may result in a variety of human diseases are found in residential homes and yards. The growth of these microscopic fungi is often favored by particular characteristics of the dwelling and nearby outdoor environment. Evolved virulence factors or increased ability of specific fungi to grow in diverse, and sometimes harsh, microenvironments presented by the domestic environment may promote growth and pathogenesis. Infection may occur by inhalation or direct inoculation and include endemic fungi in addition to opportunistic or emerging species. Systemic or locally aggressive fungal infections are particularly likely and may be life-threatening in ...


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