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Articles 14791 - 14820 of 17792
Full-Text Articles in Entire DC Network
Conceptualizing And Improving Red Wine Grape Cultivars Grown In Kentucky, Matthew Simson
Conceptualizing And Improving Red Wine Grape Cultivars Grown In Kentucky, Matthew Simson
University of Kentucky Master's Theses
Wine sensory attributes are associated with quality of wines. Cabernet Franc did not possess good coloration of its wine. Therefore, in the 2009 and 2010 growing seasons, studies including the sampling of four red wine grape cultivars from the end of flowering throughout the rest of the season and applying treatments to Cabernet Franc grapevines at veraison were commenced to address suitability and color enhancement, respectively. The study examining Cabernet Franc, Cabernet Sauvignon, Chambourcin, and Norton looked at sampling their grapes at two-week intervals from times post-flowering to understand the demands of each cultivar during key stages of berry development, …
Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton
Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton
University of Kentucky Master's Theses
Currently, bacterial movement in karst aquifers is not well understood. Use of stable isotopes to label non-pathogenic Escherichia coli as a particulate groundwater tracer in karst systems has been examined in previous studies. Loss of the stable isotope signal is anticipated in traces greater than 500 m in length. Potential loss of 15N due to predation by protozoa was examined. Filter-sterilized water from Royal Spring in Georgetown, Kentucky, was inoculated with a mixture of either Tetrahymena pyriformis or Colpoda steinii and 15N-enriched E. coli and stored in the dark at 14°C. Samples were analyzed for their nitrogen isotope …
Stories Of The Proterozoic Earth: Paleoproterozoic Chuanlinggou Arcitarchs And Neoproterozoic ¹⁷O-Depleted Barite, Yongbo Peng
Stories Of The Proterozoic Earth: Paleoproterozoic Chuanlinggou Arcitarchs And Neoproterozoic ¹⁷O-Depleted Barite, Yongbo Peng
LSU Doctoral Dissertations
This dissertation consists of two independent topics, both critical to understanding Earth history during the Proterozoic Eon. (1) Paleoproterozoic Chuanlinggou Acritarchs: The eukaryotic affinity of acritarchs from the Chuanlinggou Formation has been questioned because of lack of indisputable morphological evidence. In this study, Chuanlinggou acritarchs were examined by jointly using optical microscopy, scanning electron microscopy, and transmission electron microscopy. In most cases, an ovoidal group of acritarchs represents a half-vesicle following a complete longitudinal rupture, which is a morphological model different from a whole envelope with medial splits, as proposed by earlier studies. This ovoidal group displays a bipolar morphology, …
Phylogenetic Relationships Of The Metazoan Parasites Of The Clariid Fishes Of Lake Victoria Inferred From Partial 18s Rdna Sequences, C. J. Mwita, G. Nkwengulila
Phylogenetic Relationships Of The Metazoan Parasites Of The Clariid Fishes Of Lake Victoria Inferred From Partial 18s Rdna Sequences, C. J. Mwita, G. Nkwengulila
Tanzania Journal of Science
Phylogenetic relationships among twenty two metazoan parasites recovered from seven species of clariid fish from Lake Victoria were analysed using partial 18S rDNA sequences. The 18S rDNA gene was amplified by polymerase chain reaction, directly sequenced, aligned and phylogenies inferred using maximum parsimony. Heuristic bootstrap MP searches yielded one most parsimonious tree (CI = 61%, HI = 39%), which showed that clariid parasites are monophyletic at higher taxonomic levels (Cestodea, Nematodea, Digenea and Crustacea). However the position of two trematodes (Allocredium mazoensis and Clinostomum sp.) and a nematode (Contracaecum sp.) were not stable. Despite the present findings, the study utilised …
Due Diligence And Demographic Disparities: Effects Of The Planning Of U.S.- Mexico Border Fence On Marginalized Populations, J. Gaines Wilson, Jude A. Benavides, Karen Engle, Denise Gilman, Anthony Reisinger, Jessica Spangler, Joe Lemen
Due Diligence And Demographic Disparities: Effects Of The Planning Of U.S.- Mexico Border Fence On Marginalized Populations, J. Gaines Wilson, Jude A. Benavides, Karen Engle, Denise Gilman, Anthony Reisinger, Jessica Spangler, Joe Lemen
School of Earth, Environmental, & Marine Sciences Faculty Publications
In the buildup to the construction the U.S.-Mexico border fence by the United States Department of Homeland Security (USDHS), much attention was drawn to security, drug enforcement, and immigration issues. However, there was little quantitative analysis regarding which populations were most likely to be affected by the proposed fence. Using a geographic information system, we classified census blocks in Cameron County, Texas into one of two categories: either ‘fence’ or ‘gap’. A total of 14 demographic factors were tested for disparities between those living in gap areas and those living in areas exposed to the fence. Twelve of fourteen factors …
Investigation Of Spatial And Temporal Processes Of Lake–Aquifer Interactions In The Nebraska Sand Hills, John T. Ong
Investigation Of Spatial And Temporal Processes Of Lake–Aquifer Interactions In The Nebraska Sand Hills, John T. Ong
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
Interaction between surface water and groundwater is an important component of the water cycle that affects the physicochemical and biological characteristics of lakes, streams, wetlands, and seacoasts. Due to the complex interaction of geologic, topographic, and hydrologic factors, flow between lakes and groundwater remains poorly understood. Evolution of conceptual models over the past 30 years describes processes of advection, dispersion, and free convection that occur in different lake flow regimes. Few detailed field studies document the validity of these conceptual models because of the difficulty of studying the subsurface and the prohibitive cost of instrumenting large areas. In the semi-arid …
An Application And Refinement Of The Karst Disturbance Index Through Evaluating Variability In Island Karst Disturbance In Puerto Rico, Brandon Lee Porter
An Application And Refinement Of The Karst Disturbance Index Through Evaluating Variability In Island Karst Disturbance In Puerto Rico, Brandon Lee Porter
Masters Theses & Specialist Projects
Karst environments are unique landscapes that contain important resources, including freshwater aquifers and specialized ecosystems, which are easily disturbed due to the interconnected nature of the surface and subsurface. The anthropogenic impacts on karst are deleterious to the ecosystems that are dependent on the karst environment and also to groundwater supplies. The Karst Disturbance Index (KDI) is a holistic tool used to measure anthropogenic impacts associated with karst environments, which has been applied and refined through studies performed in Florida and Italy, yet still remains untested and susceptible to modification for other areas. Application of the KDI in Arecibo, Puerto …
Geophysics At The Interface: Response Of Geophysical Properties To Solid-Fluid, Fluid-Fluid, And Solid-Solid Interfaces, Rosemary Knight, Laura J. Pyrak-Nolte, Lee D. Slater, Estella A. Atekwana, Anthony L. Endres, Jil T. Geller, David P. Lesmes, Seiji Nakagawa, Andre Revil, Mukul M. Sharma, Christian Straley
Geophysics At The Interface: Response Of Geophysical Properties To Solid-Fluid, Fluid-Fluid, And Solid-Solid Interfaces, Rosemary Knight, Laura J. Pyrak-Nolte, Lee D. Slater, Estella A. Atekwana, Anthony L. Endres, Jil T. Geller, David P. Lesmes, Seiji Nakagawa, Andre Revil, Mukul M. Sharma, Christian Straley
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Laboratory studies reveal the sensitivity of measured geophysical properties to solid-fluid, fluid-fluid, and solid-solid interfaces in granular and fractured materials. In granular materials, electrical properties and nuclear magnetic resonance relaxation times exhibit a strong dependence on the size and properties of the solid-fluid interface. The electrical and seismic properties of granular materials and the seismic properties of fractured materials reveal a dependence on the size or geometry of fluid-fluid interfaces. Seismic properties of granular and fractured materials are affected by the effective stress and cementing material at solid-solid interfaces. There have been some recent studies demonstrating the use of field-scale …
The River Discontinuum: Applying Beaver Modifications To Baseline Conditions For Restoration Of Forested Headwaters, Denise Burchsted, Melinda Daniels, Robert Thorson, Jason Vokoun
The River Discontinuum: Applying Beaver Modifications To Baseline Conditions For Restoration Of Forested Headwaters, Denise Burchsted, Melinda Daniels, Robert Thorson, Jason Vokoun
Center for Integrative Geosciences
Billions of dollars are being spent in the United States to restore rivers to a desired, yet often unknown, reference condition. In lieu of a known reference, practitioners typically assume the paradigm of a connected watercourse. Geological and ecological processes, however, create patchy and discontinuous fluvial systems. One of these processes, dam building by North American beavers (Castor canadensis), generated discontinuities throughout precolonial river systems of northern North America. Under modern conditions, beaver dams create dynamic sequences of ponds and wet meadows among free-flowing segments. One beaver impoundment alone can exceed 1000 meters along the river, flood the valley laterally, …
Pilot-Scale Constructed Wetland Treatment System For Ammonia Removal From Oil-Field Produced Water, Yun Song
Pilot-Scale Constructed Wetland Treatment System For Ammonia Removal From Oil-Field Produced Water, Yun Song
All Theses
This investigation examined the feasibility of using free-water surface constructed wetland systems (CWTSs) to decrease the ammonia concentration in oil-field produced water. The objective of this research was to design constructed wetland experiments to determine specific conditions that decrease aqueous ammonia concentrations in simulated oilfield produced water. The design of these experiments was based on biogeochemical pathways of nitrification and denitrification. The experiments included three scales: bench-scale, single-cell, and pilot-scale. Bench-scale reactors contained wetland plants (Typha latifolia) and hydrosoil in 5-gallon buckets. Single wetland cells were constructed by adding hydrosoil and plants (T. latifolia and Schoenoplectus californicus) to 70-gallon containers. …
Phosphorus Export From A Restored Wetland Ecosystem In Response To Natural And Experimental Hydrologic Fluctuations, Marcelo Ardón, Shaena Montanari, Jennifer L. Morse, Martin W. Doyle, Emily S. Bernhardt
Phosphorus Export From A Restored Wetland Ecosystem In Response To Natural And Experimental Hydrologic Fluctuations, Marcelo Ardón, Shaena Montanari, Jennifer L. Morse, Martin W. Doyle, Emily S. Bernhardt
Environmental Science and Management Faculty Publications and Presentations
Wetland restoration is a commonly used approach to reduce nutrient loading to freshwater and coastal ecosystems, with many wetland restoration efforts occurring in former agricultural fields. Restored wetlands are expected to be effective at retaining or removing both nitrogen and phosphorus (P), yet restoring wetland hydrology to former agricultural fields can lead to the release of legacy fertilizer P. Here, we examined P cycling and export following rewetting of the Timberlake Restoration Project, a 440 ha restored riverine wetland complex in the coastal plain of North Carolina. We also compared P cycling within the restored wetland to two minimally disturbed …
The Effect Of Enso On Nebraska Winter Snowfall, Jonathan Burnham
The Effect Of Enso On Nebraska Winter Snowfall, Jonathan Burnham
Department of Environmental Studies: Undergraduate Student Theses
No abstract provided.
Late Holocene Relationships Among Fire, Climate, And Vegetation In Rangeland Ecosystems Of Southwestern Idaho, Nathan A. Nelson, Jennifer Pierce
Late Holocene Relationships Among Fire, Climate, And Vegetation In Rangeland Ecosystems Of Southwestern Idaho, Nathan A. Nelson, Jennifer Pierce
Geosciences Faculty Publications and Presentations
Rangelands are characterized by more arid climates than forested regions; therefore, establishing fire histories using traditional methods (e.g. fire-scars from trees or charcoal in lake sediments) is problematic. This study uses radiocarbon dating of charcoal preserved in alluvial fans and stream deposits to reconstruct a record of fire and geomorphic response in rangelands of southwestern Idaho. Samples indicate three primary periods of fire-related activity: 4400 – 4000, 2000 – 1400, and 650-400 cal yr BP. Charcoal macrofossil identification and comparison with other regional climate and fire records indicate this area has likely switched between a "fuel-limited" system (fires limited by …
Characterization Of Watersheds On Fort Benning Military Reservation: Comparison Of Field Data To Watershed Parameters, Melinda Rosetta Stahl
Characterization Of Watersheds On Fort Benning Military Reservation: Comparison Of Field Data To Watershed Parameters, Melinda Rosetta Stahl
Theses and Dissertations
Sixteen watersheds located on Fort Benning Military Installation in Georgia were analyzed using both physically collected data and computer modeling data. Physical data collected included total suspended solids (TSS) and grain size analysis using the Wolman Pebble Count method. Computer modeling analyzed the watersheds using ArcGIS 9.3 for comparison to physical data. Land use, slope, and soil data were used in a modified revised universal soil loss equation (RUSLE) to create a soil erodibility index map. Wolman Pebble Count data showed that in half of the watersheds, 84% of the sampled grains were less than half a millimeter in size. …
Evaluation Of A Pilot-Scale Constructed Wetland Treatment System For Renovation Of A Specific Oilfield Produced Water For Beneficial Use, Jennifer Horner
Evaluation Of A Pilot-Scale Constructed Wetland Treatment System For Renovation Of A Specific Oilfield Produced Water For Beneficial Use, Jennifer Horner
All Theses
Oilfield produced waters (OPWs) are brought to the surface when oil reservoirs contained in water-bearing geologic units are extracted. Large volumes of OPW present environmental challenges concerning disposal, as well as potential opportunities for beneficial use if constituents posing risk can be remediated. In this study a pilot-scale constructed wetland treatment system (CWTS) was specifically designed to treat an OPW from sub-Saharan Africa for use in irrigation and livestock watering. Three major objectives were to: characterize and identify constituents of concern in the OPW in terms of beneficial use, evaluate treatment performance of a pilot-scale constructed wetland treatment system for …
Carbon Isotopic Fractionation Across A Late Cambrian Carbonate Platform: A Regional Response To The Spice Event As Recorded In The Great Basin, Jonathan Lloyd Baker
Carbon Isotopic Fractionation Across A Late Cambrian Carbonate Platform: A Regional Response To The Spice Event As Recorded In The Great Basin, Jonathan Lloyd Baker
UNLV Theses, Dissertations, Professional Papers, and Capstones
Geochemical models have suggested that the late Cambrian was characterized by a greenhouse climate with high pCO2. Furthermore, stableisotope analyses within the Great Basin have documented a large carbonate isotope (δ13Ccarb) excursion, known as the Steptoean Positive Carbon Isotope Excursion (SPICE). This event has been documented globally, and is interpreted as having resulted from enhanced organic carbon burial. Unless the size of carbon reservoirs in the Cambrian ocean was significantly different from those of the Cenozoic, this forcing should have resulted in a comparable carbon-isotope excursion in organic matter (δ13Corg). It is also predicted that increased organic carbon burial would …
Effect Of Spatial And Temporal Variability Of Antecedent Moisture Content On Model-Generated Runoff From An Arid Watershed, William J. Meyer
Effect Of Spatial And Temporal Variability Of Antecedent Moisture Content On Model-Generated Runoff From An Arid Watershed, William J. Meyer
UNLV Theses, Dissertations, Professional Papers, and Capstones
Streams in the arid southwest are typically ephemeral, and stream gages are not commonly available. Consequently, runoff data from storm events is not available, and flood control facility design or other water resource related decisions are based on synthetic hydrographs. In the Mojave Desert region of Southern Nevada, the duration of storm used to develop these synthetic hydrographs is the 6 hour storm. The 6 hour storm is used to simulate high intensity summer storms. Additionally, soils information used in the calculations for these synthetic hydrographs is taken from maps that are generally developed for a broad range of issues …
A Comprehensive Uncertainty Analysis And Method Of Geometric Calibration For A Circular Scanning Airborne Lidar, Michael Oliver Gonsalves
A Comprehensive Uncertainty Analysis And Method Of Geometric Calibration For A Circular Scanning Airborne Lidar, Michael Oliver Gonsalves
Dissertations
This dissertation describes an automated technique for ascertaining the values of the geometric calibration parameters of an airborne lidar. A least squares approach is employed that adjusts the point cloud to a single planar surface which could be either a narrow airport runway or a dynamic sea surface. Going beyond the customary three boresight angles, the proposed adjustment can determine up to eleven calibration parameters to a precision that renders a negligible contribution to the point cloud’s positional uncertainty.
Presently under development is the Coastal Zone Mapping and Imaging Lidar (CZMIL), which, unlike most contemporary systems that use oscillating mirrors …
Effect Of Mica Content On Surface Infiltration Of Soils In Northwestern Kern County, California, Steven Keyes Stakland
Effect Of Mica Content On Surface Infiltration Of Soils In Northwestern Kern County, California, Steven Keyes Stakland
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A soils infiltration rate (IR) is the measured rate that soil is able to absorb water, either from precipitation or irrigation. A low IR can cause damage to crops if the necessary amount of water cannot penetrate to the plant roots in the time needed. The damage can be common in permanent plantings such as almond and pistachio orchards where regular tillage is avoided. This indicates a physical aspect to the problem because tillage increases IR. However, there is also an electrochemical side to infiltration problems because certain calcium surfactant treatments can increase IR. Various other methods have been used …
The Distribution And Comparative Biogeochemistry Of Silver With Other Selected Trace Metals In Coastal Waters Near Massachusetts, Usa, Christian F. Krahforst
The Distribution And Comparative Biogeochemistry Of Silver With Other Selected Trace Metals In Coastal Waters Near Massachusetts, Usa, Christian F. Krahforst
Graduate Doctoral Dissertations
Water samples and hydrologic data were collected during 1994-1996 in New England coastal waters near Massachusetts, USA to examine the distribution of silver and other trace metals (Cu, Pb, Cd, Zn, and Fe) in the coastal systems of Massachusetts and Cape Cod Bays. These investigations were designed to test the hypothesis that silver could serve as a tracer of dispersion of municipal wastewater in Boston Harbor into Massachusetts and Cape Cod Bays and estimate the relative contribution of wastewater discharge to the overall silver budget of the Massachusetts Bays system. Silver concentrations in both particulate and filtered (<0.4 µm) fractions averaged 103 and 117 pmol kg-1 for Boston Harbor, 34 and 10 pmol kg-1 in western Massachusetts Bay, and 11 and 7 pmol kg-1 in the central portion of Massachusetts Bay, respectively. Average Ag concentrations in southern Gulf of Maine coastal waters were 10 and 2 pmol kg-1 for filtered and particulate fractions, respectively. While nearly half of the silver existed in particulate form in Boston Harbor, nearly 80% of the silver in Massachusetts and Cape Cod Bays occurred in the filterable fraction. Coastal water surveys revealed non-conservative Ag behavior and probably the result of incomplete mixing of three or more water masses with unique Ag signatures (e.g., Merrimack River, Boston Harbor, surface and intermediate Gulf of Maine waters). Quasi-steady state mass balance approaches estimate most of the silver entering into the Massachusetts Bays system during the study period was the result of municipal wastewater discharge to Boston Harbor (84-93%).
Multivariate analyses …
0.4>Stable Isotopes Of Fossil Teeth Corroborate Key General Circulation Model Predictions For The Last Glacial Maximum In North America, Matthew J. Kohn, Moriah Mckay
Stable Isotopes Of Fossil Teeth Corroborate Key General Circulation Model Predictions For The Last Glacial Maximum In North America, Matthew J. Kohn, Moriah Mckay
Geosciences Faculty Publications and Presentations
Oxygen isotope data provide a key test of general circulation models (GCMs) for the Last Glacial Maximum (LGM) in North America, which have otherwise proved difficult to validate. High δ18O pedogenic carbonates in central Wyoming have been interpreted to indicate increased summer precipitation sourced from the Gulf of Mexico. Here we show that tooth enamel δ18O of large mammals, which is strongly correlated with local water and precipitation δ18O, is lower during the LGM in Wyoming, not higher. Similar data from Texas, California, Florida and Arizona indicate higher δ18O values than in the Holocene, which is also predicted by GCMs. …
Modern Variation In Predation Intensity: Constraints On Assessing Predator-Prey Relationships In Paleoecologic Reconstructions, James Funderburk
Modern Variation In Predation Intensity: Constraints On Assessing Predator-Prey Relationships In Paleoecologic Reconstructions, James Funderburk
USF Tampa Graduate Theses and Dissertations
The complex interaction between predators and their prey is rarely preserved in the fossil record. However, predation of marine mollusks by drilling gastropods leaves a diagnostic hole in the shell of the prey, possibly allowing for quantitative analysis of this ecological interaction. Drilling frequency, as measured in marine mollusks both in the Modern and fossil record, has been heralded as a potential opportunity to quantify these ecological interactions and use these values in the testing of hypotheses.
This study employed the collection, tallying, and analysis of bulk samples derived from shelly deposits on 45 Modern beaches along the contiguous coast …
Carbon Isotope Compositions Of Terrestrial C3 Plants As Indicators Of (Paleo)Ecology And (Paleo)Climate, Matthew J. Kohn
Carbon Isotope Compositions Of Terrestrial C3 Plants As Indicators Of (Paleo)Ecology And (Paleo)Climate, Matthew J. Kohn
Geosciences Faculty Publications and Presentations
A broad compilation of modern carbon isotope compositions in all C3 plant types shows a monotonic increase in δ13C with decreasing mean annual precipitation (MAP) that differs from previous models. Corrections for temperature, altitude, or latitude are smaller than previously estimated. As corrected for altitude, latitude, and the δ13C of atmospheric CO2, these data permit refined interpretation of MAP, paleodiet, and paleoecology of ecosystems dominated by C3 plants, either prior to 7–8 million years ago (Ma), or more recently at mid- to high latitudes. Twenty-nine published paleontological studies suggest preservational or scientific bias toward …
Loring-Greenough House, North Yard Archaeogeophysics, Jamaica Plain, Massachusetts, John M. Steinberg, Christa M. Beranek, John Schoenfelder, Kathryn A. Catlin
Loring-Greenough House, North Yard Archaeogeophysics, Jamaica Plain, Massachusetts, John M. Steinberg, Christa M. Beranek, John Schoenfelder, Kathryn A. Catlin
Andrew Fiske Memorial Center for Archaeological Research Publications
An archaeogeophysical survey was carried out in May 2010 using Geonics EM-38 RT and a Malå Ground Penetrating Radar (GPR) system with a 500 MHz antenna over an 28x26 m grid immediately northeast of the Loring-Greenough house in Jamaica Plain, MA. Three major anomalies were identified. These anomalies have not been ground truthed, but they appear to be archaeological features. First, we suggest that there is builders trench just north of the house. Second, we suggest that there could be three east-west garden paths or other landscape features about 30 cm below the surface crossing the entire length of the …
Spatial Similarities And Differences Of Attributes Of Three Subwatersheds Within The Middle Smoky Hill River Watershed And Their Relationship To Instream Total Suspended Solids, Dustin Fross
Master's Theses or Doctor of Nursing Practice
The objective of this study was to spatially analyze the attributes of three subwatersheds, Hydrological Unit Code 12 (HUC 12), of the Middle Smoky Hill River Watershed in west-central Kansas and relate the variances of the attributes to the concentrations of total suspended solids (TSS) entering the Smoky Hill River during storm events. This was accomplished by comparing land cover, including cropland, grassland, and urban factors; agricultural practices, such as tillage methods, condition of terraces, and the presence of grass waterways; geomorphology, including soil types, topography, and visible erosion; and lastly, precipitation variance. The three HUC 12s that were studied …
Bedrock Erosion By Root Fracture And Tree Throw: A Coupled Biogeomorphic Model To Explore The Humped Soil Production Function And The Persistence Of Hillslope Soils, Emmanuel Gabet, Simon Mudd
Bedrock Erosion By Root Fracture And Tree Throw: A Coupled Biogeomorphic Model To Explore The Humped Soil Production Function And The Persistence Of Hillslope Soils, Emmanuel Gabet, Simon Mudd
Faculty Publications
In 1877, G. K. Gilbert reasoned that bedrock erosion is maximized under an intermediate soil thickness and declines as soils become thinner or thicker. Subsequent analyses of this “humped” functional relationship proposed that thin soils are unstable and that perturbations in soil thickness would lead to runaway thinning or thickening of the soil. To explore this issue, we developed a numerical model that simulates the physical weathering of bedrock by root fracture and tree throw. The coupled biogeomorphic model combines data on conifer population dynamics, rootwad volumes, tree throw frequency, and soil creep from the Pacific Northwest (USA). Although not …
Molecular Mechanisms Of Persistence Of Mutualistic Bacteria Photorhabdus In The Entomopathogenic Nematode Host, Ruisheng An, Parwinder Grewal
Molecular Mechanisms Of Persistence Of Mutualistic Bacteria Photorhabdus In The Entomopathogenic Nematode Host, Ruisheng An, Parwinder Grewal
School of Earth, Environmental, & Marine Sciences Faculty Publications
Symbioses between microbes and animals are ubiquitous, yet little is known about the intricate mechanisms maintaining such associations. In an emerging mutualistic model system, insect-pathogenic bacteria Photorhabdus and their insect-parasitic nematode partner Heterorhabditis, we found that the bacteria undergo major transcriptional reshaping in the nematode intestine. Besides general starvation mechanisms, the bacteria induce cellular acidification to slow down growth, switch to pentose phosphate pathway to overcome oxidative stress and nutrition limitation, and shed motility but develop biofilm to persist in the nematode intestine until being released into the insect hemolymph. These findings demonstrate how the symbiotic bacteria reduce their …
Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology
Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology
Earth, Environmental, and Atmospheric Sciences Publications
No abstract provided.
Droughtscape, Fall 2010, Kelly Smith
Droughtscape, Fall 2010, Kelly Smith
DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)
CDC Issues Drought Guidance for Public Health
La Niña May Intensify Drought in South
Recent Workshops and Meetings
East Feels Impacts as Heat Intensifies Drought
New Products
Nicole Wall Co-Facilitates Republican River Basin Task Force
NDMC Climatologist on Ethiopia Team
Earth News, V34, Fall 2010, Department Of Earth Science, University Of Northern Iowa.
Earth News, V34, Fall 2010, Department Of Earth Science, University Of Northern Iowa.
Earth News
Inside this issue:
--- Faculty & Staff News
--- Sunday at the Quarry
--- Studies in Air Quality for Science Educators
--- Geology for Iowa Teachers
--- IMSEP Workshop
--- Grant Activities in Hydrologic Sciences
--- IGEIN / GSI Field Trip
--- EDMAP
--- Student Research Presentations
--- Internships / Seminars
--- Graduates / SGE
--- Scholarships & Awards
--- Making a Difference / NAGT Award
--- UNI Alum: Brian Hynek
--- UNI Alum: Mary Lestina
--- Gifts
--- Alumni News