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Investigations Of Rhizobium Biofilm Formation, Nancy Fujishige
Investigations Of Rhizobium Biofilm Formation, Nancy Fujishige
Biology Faculty Works
The development of nitrogen-fixing nodules of the Rhizobium-legume symbiosis, especially the early stages of root hair deformation and curling, infection thread formation, and nodule initiation, has been well studied from a genetic standpoint. In contrast, the factors important for the colonization of surfaces by rhizobia, including roots-an important prerequisite for nodule formation-have not been as thoroughly investigated. We developed conditions for analyzing the ability of two fast-growing rhizobia, Sinorhizobium meliloti and Rhizobium leguminosarum bv. viciae, to produce biofilms on abiotic surfaces such as glass, plastic microtiter plates, sand and soil as a prelude to characterizing the genes important for aggregation …
Comparison Of Geometric Morphometric Outline Methods In The Discrimination Of Age-Related Differences In Feather Shape, Kristen M. Covino
Comparison Of Geometric Morphometric Outline Methods In The Discrimination Of Age-Related Differences In Feather Shape, Kristen M. Covino
Biology Faculty Works
Background: Geometric morphometric methods of capturing information about curves or outlines of organismal structures may be used in conjunction with canonical variates analysis (CVA) to assign specimens to groups or populations based on their shapes. This methodological paper examines approaches to optimizing the classification of specimens based on their outlines. This study examines the performance of four approaches to the mathematical representation of outlines and two different approaches to curve measurement as applied to a collection of feather outlines. A new approach to the dimension reduction necessary to carry out a CVA on this type of outline data with modest …
Impaired Glutamate Transport In A Mouse Model Of Tau Pathology In Astrocytes, Deepa V. Dabir
Impaired Glutamate Transport In A Mouse Model Of Tau Pathology In Astrocytes, Deepa V. Dabir
Biology Faculty Works
Filamentous tau inclusions in neurons and glia are neuropathological hallmarks of tauopathies. The discovery of microtubule-associated protein tau gene mutations that are pathogenic for a heterogenous group of neurodegenerative disorders, called frontotemporal dementia and parkinsonism linked to chromosome-17 (FTDP-17), directly implicate tau abnormalities in the onset/progression of disease. Although the role of tau pathology in neurons in disease pathogenesis is well accepted, the contribution of glial pathology is essentially unknown. We recently generated a transgenic (Tg) mouse model of tau pathology in astrocytes by expressing the human tau protein under the control of the glial fibrillary acidic protein (GFAP) promoter. …
Rat Poison Kills A Pack Of Eastern Coyotes, Canis Latrans, In An Urban Area, Eric Strauss
Rat Poison Kills A Pack Of Eastern Coyotes, Canis Latrans, In An Urban Area, Eric Strauss
Biology Faculty Works
We document the death of a pack of Eastern Coyotes (Canis latrans) from high levels of brodifacoum, a second generation poison that is the active ingredient in some forms of rat poison (e.g., d-Con®). The Coyotes died within a week of each other during late March/early April 2005. This incident indicates the vulnerability of wild animals to commercial over-the-counter rodenticides.
An Ethogram Developed On Captive Eastern Coyotes Canis Latrans, Eric Strauss
An Ethogram Developed On Captive Eastern Coyotes Canis Latrans, Eric Strauss
Biology Faculty Works
We studied capture Eastern Coyotes (Canis latrans) from 27-585 days of age and compiled an ethogram on them. A total of 72247 15-sec samples were taken, amounting to 301 h of field time varying between 59.4-61.3 h per Coyote. A total of 540 behavioral patterns was observed amongst the 16 behaviour categories ranging from 9 (miscellaneous) to 72 (explore/investigate) action patterns per parent category. The 16 parent categories that we believed best described and appropriately sorted the behavioural actions were resting, sitting, sitting1, sitting2, standing, traveling, explore/investigating, hunting, feeding, infantile, greeting, self play, play initiating, playing, agonistic, and miscellaneous. Exploring …
Standard And Routine Metabolic Rates Of Juvenile Sandbar Sharks (Carcharhinus Plumbeus), Including The Effects Of Body Mass And Acute Temperature Change, W. Wesley Dowd, Richard W. Brill, Peter G. Bushnell, John A. Musick
Standard And Routine Metabolic Rates Of Juvenile Sandbar Sharks (Carcharhinus Plumbeus), Including The Effects Of Body Mass And Acute Temperature Change, W. Wesley Dowd, Richard W. Brill, Peter G. Bushnell, John A. Musick
Biology Faculty Works
Standard and routine metabolic rates (SMRs and RMRs, respectively) of juvenile sandbar sharks (Carcharhinus plumbeus) were measured over a range of body sizes (n=34) and temperatures normally associated with western Atlantic coastal nursery areas. The mean SMR Q10 (increase in metabolic rate with temperature) was 2.9 ±0.2. Heart rate decreased with increasing body mass but increased with temperature at a Q10 of 1.8−2.2. Self-paired measures of SMR and RMR were obtained for 15 individuals. Routine metabolic rate averaged 1.8 ±0.1 times the SMR and was not correlated with body mass. Assuming the maximum metabolic rate of sandbar sharks is 1.8−2.75 …
A Feeling For The Micro-Organism: Structure On A Small Scale. Biofilms On Plant Roots, Nancy Fujishige
A Feeling For The Micro-Organism: Structure On A Small Scale. Biofilms On Plant Roots, Nancy Fujishige
Biology Faculty Works
Biofilms are structured communities of bacterial cells enclosed in a self-produced polymeric matrix and adherent to an inert or living surface; they have clinical, industrial and environmental impacts. Biofilms that are established by bacteria on plants are found on the surfaces of roots, leaves, seeds and internal vascular tissues where the microbes live in commensal, mutualistic or parasitic/pathogenic associations with their host. The study of the structure of plant-associated biofilms has been considerably helped by the development of techniques using fluorescent markers coupled with confocal scanning laser microscopy as well as scanning electron microscopy. We review several of these techniques …
Estimating Consumption Rates Of Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Chesapeake Bay, Virginia, Using A Bioenergetics Model, W. Wesley Dowd, Richard W. Brill, Peter G. Bushnell, John A. Musick
Estimating Consumption Rates Of Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Chesapeake Bay, Virginia, Using A Bioenergetics Model, W. Wesley Dowd, Richard W. Brill, Peter G. Bushnell, John A. Musick
Biology Faculty Works
Using a bioenergetics model, we estimated daily ration and seasonal prey consumption rates for six age classes of juvenile sandbar sharks (Carcharhinus plumbeus) in the lower Chesapeake Bay summer nursery area. The model, incorporating habitat and species-specific data on growth rates, metabolic rate, diet composition, water temperature (range 16.8−27.9°C), and population structure, predicted mean daily rations between 2.17 ±0.03 (age-0) and 1.30 ±0.02 (age-5) % body mass/day. These daily rations are higher than earlier predictions for sandbar sharks but are comparable to those for ecologically similar shark species. The total nursery population of sandbar sharks was predicted to consume ~124,000 …