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New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly Aug 2023

New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly

Electronic Theses and Dissertations

Dryolestoids are extinct cladotherians mammals from the Jurassic and Cretaceous periods. I describe a collection of dryolestoid specimens from the Late Cretaceous localities of Cerro Tortuga (Allen Formation), Anfiteatro 1, and Shining (both La Colonia Formation) from Patagonia, Argentina. Using comparative morphology, I identify a new species of meridiolestidan dryolestoid based on eleven specimens across both formations. The new species’ recovery from La Colonia Formation represents the first dryolestoid connection between the two approximately contemporaneous formations. The species’ morphology may represent an ecological shift within Meridiolestida from insectivory to herbivory, showing a transition in characters between the plesiomorphic sharp-toothed meridiolestidans …


Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander May 2020

Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander

Electronic Theses and Dissertations

Background: Tobacco smoking is the leading environmental risk factor for periodontal diseases. Delineation of the mechanisms underlying tobacco-induced or exacerbated periodontitis is hampered by the lack of an appropriate and reliable animal model. Hypothesis: We hypothesized that Porphyromonas-gingivalis-infected, cigarette smoke-exposed mice would represent reproducible models of acute (ligature model) and chronic (oral gavage model) tobacco-enhanced periodontitis that reflect multiple aspects of the disease noted in human smokers. Methods: In a chronic oral gavage disease model, Balb/c mice (6-8 weeks, 4 groups of n = 6 per group) were exposed to smoke produced by a Teague-10 smoking machine from 1R6F research …


The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley Aug 2018

The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley

Electronic Theses and Dissertations

The Cave Salamander, Eurycea lucifuga (Rafinesque, 1822), is a little-known species, yet a common inhabitant of caves in the eastern United States. Salamanders are often important components of ecological communities and ecosystems, influencing critical processes such as nutrient cycling and community composition through their predation on invertebrates. Cave-dwelling salamanders such as E. lucifuga may thus appreciably influence the relatively simple ecosystems and communities of caves. Any such influence may be particularly important because these habitats and the organisms that reside in them are often of conservation concern. I used non-invasive methods to study the demographics, movements, and habitat selection of …


The Effects Of Habitat And Connectivity On Tropical Ant Ecology And Behavior., Benjamin Jacob Adams May 2018

The Effects Of Habitat And Connectivity On Tropical Ant Ecology And Behavior., Benjamin Jacob Adams

Electronic Theses and Dissertations

This dissertation explores the role that physical connections among and within habitats play in determining the local diversity and behaviors of cursorial organisms. Understanding the processes that regulate local community assembly and that contribute to the maintenance of species diversity is a cornerstone of community ecology. Ants are a useful model for studies of local communities because they are abundant and fulfill a variety of ecological roles. Chapter one of the dissertation examines the how lianas (woody vines) function as connective structures among tree crowns and how these connections affect arboreal ant community structure within a tropical forest canopy. Trees …


Impact Of Urban Factors And Invasive Species On White-Footed Mouse (Peromyscus Leucopus) Habitat Use And Foraging Behavior In An Urban Forest Park., William Persons Dec 2015

Impact Of Urban Factors And Invasive Species On White-Footed Mouse (Peromyscus Leucopus) Habitat Use And Foraging Behavior In An Urban Forest Park., William Persons

Electronic Theses and Dissertations

White-footed mice (Peromyscus leucopus) select for areas of greater canopy cover at the macro scale, and for areas with more CWD at the micro-scale. White-footed mice potentially avoid habitats with higher invasive species richness. White-footed mice preferentially foraged under the honeysuckle canopy in response to changes in temperature and humidity. This study suggests that the interaction between P. leucopus and ground layer invasive species is complex, and that the effect of moonlight may be diminished in this urban park. Urban ecosystems demonstrate high levels of anthropogenic land-use change, modification of abiotic inputs, and altered disturbance regimes. These changes result …


Effects Of Step Training On The Kidneys Following Spinal Cord Injury In Rats., Pradeepa Poudyal Dec 2014

Effects Of Step Training On The Kidneys Following Spinal Cord Injury In Rats., Pradeepa Poudyal

Electronic Theses and Dissertations

Detrusor-sphincter dyssynergia after chronic spinal cord injury (SCI) leads to over-distention, high bladder pressures and vesico-ureteric reflux into the kidney, resulting in repeated infections and pyelonephritis. Given the importance/limited knowledge of SCI effects on the upper urinary tract, this study assessed expression of two proteins in the kidneys of contused (T9) male rats relative to controls that are indicative of tissue stress/damage (TGFβ, CD11b). The impact of two therapeutic rehabilitation strategies, 60 minutes of step training and general exercise, was then assessed on these protein levels relative to non-trained SCI controls, plus the effectiveness of a shorter training duration (30 …


Earthworm, Microbial Biomass, And Leaf Litter Decay Responses After Invasive Honeysuckle Shrub Removal From Urban Woodlands., Robert Preston Pipal Dec 2014

Earthworm, Microbial Biomass, And Leaf Litter Decay Responses After Invasive Honeysuckle Shrub Removal From Urban Woodlands., Robert Preston Pipal

Electronic Theses and Dissertations

Invasive species are one of the leading causes of biodiversity loss and their presence can significantly impact the structure and function of native ecosystems. In this dissertation, the impacts of the invasive honeysuckle shrub, Lonicera maackii, on exotic earthworm populations, leaf litter decay responses, and inorganic and organic nutrient pools in an urban woodland park are assessed. Chapter 1 provides a brief review of honeysuckle's effects on forest ecosystems. Chapter 2 describes honeysuckle’s effects on exotic earthworm populations and the seasonal importance of macroinvertebrates to leaf litter decomposition in urban woodlands. This study revealed that L. maackii promoted higher exotic …


A Survey Of The Rhopalocera Of Jefferson County, Kentucky., Delbert Kenneth Weniger Jan 1946

A Survey Of The Rhopalocera Of Jefferson County, Kentucky., Delbert Kenneth Weniger

Electronic Theses and Dissertations

No abstract provided.


A Study Of Sex Differentiation In Lebistes Reticulatus As Affected By Estradiol Stilbestrol And Pregneninolon., Esther Coogle Jan 1943

A Study Of Sex Differentiation In Lebistes Reticulatus As Affected By Estradiol Stilbestrol And Pregneninolon., Esther Coogle

Electronic Theses and Dissertations

No abstract provided.


The Incidence Of Trichinella Spiralis In The Diaphragms Of Swine From The Louisville Abattoirs., Stuart Lyle Adams Jan 1942

The Incidence Of Trichinella Spiralis In The Diaphragms Of Swine From The Louisville Abattoirs., Stuart Lyle Adams

Electronic Theses and Dissertations

Trichinosis is a disease caused by the parasitic nematode Trichinella spiralis. When meat containing encysted larvae is consumed the cysts are dissolved by the action of the gastric juice in the stomach and the larvae migrate to the intestine where they mature, copulate and give birth to living young within a week of the original infection. The larvae enter the lymph spaces and are carried to the thoracic duct from which they reach the venous circulation and thence the arterial circulation by way of the heart and the pulmonary capillaries. From the arterial blood the larvae enter most of the …


The Morphogenesis Of The Pectoral Girdle Of Amblystoma Microstomum., Raymond W. Lawrence Jan 1939

The Morphogenesis Of The Pectoral Girdle Of Amblystoma Microstomum., Raymond W. Lawrence

Electronic Theses and Dissertations

No abstract provided.


A Cytological Study Of The Ciliated Epithelium Of Nucula Castrensis Hinds., Dorothy Blumer Jun 1938

A Cytological Study Of The Ciliated Epithelium Of Nucula Castrensis Hinds., Dorothy Blumer

Electronic Theses and Dissertations

Ever since the latter part of the 17th century, when ciliary movement was first observed, the study of ciliated cells has been of great interest to biologists, particularly to physiologists. In 1713 Leeuwenhoek recorded some observations he made on ciliary activity, using his primitive microscope. A knowledge of the structure and function of ciliated cells is also of importance in that branch of medicine pertaining to disorders of the respiratory passages and the movement of the ovum in the uterine tubes. The bivalve molluscs have come to be the classical example for the study of ciliated cells, both because of …


A Study Of The Relationship Between Blood Flow And Limb Volume In The Hind Limb Of The Dog., J. P. Holt Jan 1938

A Study Of The Relationship Between Blood Flow And Limb Volume In The Hind Limb Of The Dog., J. P. Holt

Electronic Theses and Dissertations

No abstract provided.


The Skeletal, Muscular, Vascular, And The Digestive Systems Of The Ferret (Mustela Putorius) And A Comparison Of These Systems With Those Of The Domestic Cat (Felis Domesticus)., Arthur Pincus Skwerer Jan 1937

The Skeletal, Muscular, Vascular, And The Digestive Systems Of The Ferret (Mustela Putorius) And A Comparison Of These Systems With Those Of The Domestic Cat (Felis Domesticus)., Arthur Pincus Skwerer

Electronic Theses and Dissertations

No abstract provided.


The Anatomy, Systematic Position, Natural History And Economic Importance Of The Spoonbill Ganoid, Polyodon Spathula., Oscar H. Steinberg Jan 1935

The Anatomy, Systematic Position, Natural History And Economic Importance Of The Spoonbill Ganoid, Polyodon Spathula., Oscar H. Steinberg

Electronic Theses and Dissertations

No abstract provided.


The Effect Of Potassium-Iodide On The Embryological Development Of The Chick With Special Reference To The Growth Of The Long Bones., David M. Polot 1904-1978 Jan 1931

The Effect Of Potassium-Iodide On The Embryological Development Of The Chick With Special Reference To The Growth Of The Long Bones., David M. Polot 1904-1978

Electronic Theses and Dissertations

No abstract provided.