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Full-Text Articles in Life Sciences
Avian Communities In An Urbanizing Region: Abundance Patterns And Effects Of Local Habitat Features, John S. Brush
Avian Communities In An Urbanizing Region: Abundance Patterns And Effects Of Local Habitat Features, John S. Brush
Theses and Dissertations
The Lower Rio Grande Valley of Texas has experience rapid population growth and increase of urban area since the mid-20th century. The goal of this thesis were to: 1) explore patterns of avian communities in suburban and remnant urban woodlands, with particular interest in native forest species, and 2) to assess how local habitat variables, such as number of native trees, affect avian communities in suburban habitats, and 3) provide recommendations to municipalities and homeowners to enhance urban habitats for birds. Results indicated that remnant urban woodlands provided habitat for common native forest bird species that otherwise avoided suburban habitats, …
Calculating Evapotranspiration Of Arundo Donax Along The Rio Grande, Jose R. Escamilla Jr.
Calculating Evapotranspiration Of Arundo Donax Along The Rio Grande, Jose R. Escamilla Jr.
Theses and Dissertations
Invasive species have been recorded to cause large economic and ecological impacts on various ecosystems and their services. Locally, giant reed (Arundo donax L.), a woody grass native to the Mediterranean, adversely impacts riparian ecosystems in southwestern United States by aggressively displacing their native flora and fauna. Giant reed also has become a cause of concern for national water security, especially in water-limited areas of the arid southwestern United States. The main objective of this study is to provide the first, landscape-level estimates of water use by giant reed in the United States. Evapotranspiration was monitored using the eddy …
Sequencing Of The Complete Mitochondrial Genome Of Anastrepha Species, Francisco C. Rugama Ii
Sequencing Of The Complete Mitochondrial Genome Of Anastrepha Species, Francisco C. Rugama Ii
Theses and Dissertations
Several members of fruit flies in the vastly diverse Anastrepha (Schinner) genus (family Tephritidae), considered to be among the most important and devastating pests of vegetable and fruit crops, are distributed widely throughout the Americas. They attack several different kinds of fruit including citrus, which is of great economical importance in South Texas. The identification of these flies is based primarily on wing pattern and characteristics of the female genitalia, contrary to males, which cannot be distinguished at all. Misidentification of adults is a widespread problem, while identification at the larval stage is practically impossible. Currently, there are no published …
Carbon And Nitrogen Dynamics Of Anthropogenically Disturbed Seagrass Ecosystems, Alison Shepherd
Carbon And Nitrogen Dynamics Of Anthropogenically Disturbed Seagrass Ecosystems, Alison Shepherd
Theses and Dissertations
As atmospheric CO2 concentrations continue to rise, understanding factors that influence size and longevity of carbon (C) pools within coastal and marine ecosystems (i.e., “blue carbon”) is critical. In 2013, the global average atmospheric CO2 concentration reached 396 ppm, which was the highest recorded level in the last 800,000 years. Recent research acknowledges the importance of “blue carbon” in the global C cycle, finding that these ecosystems capture up to 70% of organic C in the marine realm, rendering them one of the most efficient C sinks on the planet. Specifically, seagrass ecosystems are critically important to the global C …
Developing A Multimetric Index To Assess Resaca Ecosystem Health, Buford J. Lessley
Developing A Multimetric Index To Assess Resaca Ecosystem Health, Buford J. Lessley
Theses and Dissertations
As the only freshwater ecosystem in the lower Rio Grande Valley aside from the Rio itself, resacas are critical habitat for many species of flora and fauna. Old distributaries of the Rio Grande, resacas provided conveyance routes moving floodwater to the Laguna Madre. Today these wetlands are novel ecosystems and are artificially maintained. Urbanization and agriculture have lead to sedimentation, habitat loss, contaminants, poor water quality, and invasive species. The objective of this study was to assess and monitor resaca pools and to compose the Resaca Health Index (RHI) from selected indicators of ecosystem structure and function including leaf litter …
The Effect Of Manganese (Mn) On Cell Proliferation And Migration In The Michigan Cancer Foundation-7 (Mcf-7) Human Breast Cancer Cell Line In Vitro, Justin Lloyd Wendel
The Effect Of Manganese (Mn) On Cell Proliferation And Migration In The Michigan Cancer Foundation-7 (Mcf-7) Human Breast Cancer Cell Line In Vitro, Justin Lloyd Wendel
Theses and Dissertations
Manganese (Mn) is a common environmental element necessary for mammalian physiological processes. However, dietary excess or deficiency can lead to detrimental health effects. Therefore, I investigated the effect Mn has on breast cancer progression in vitro. Utilizing MCF-7 breast cancer cells an MTT assay was performed to identify proliferative potential. After 5 days, results showed 100 nM manganese chloride (MnCl2) had a significant (p<0.01) increase in cell number over control. Using a scratch wound-healing assay, 100 nM MnCl2 was found to increase cellular motility as well as induce a possible change in morphology and cytoskeletal organization. Given Mn was shown to localize in the mitochondrial, we investigated Mn-induced ROS expression. 500 nM Mn significantly decreased (p<0.05) ROS levels. Collectively, I provide evidence that Mn may potentially drive less aggressive cancer cells towards a more invasive phenotype.
South Padre Island Beach Management: Assessment Of Dune Restoration, Shelby Rose Bessette
South Padre Island Beach Management: Assessment Of Dune Restoration, Shelby Rose Bessette
Theses and Dissertations
Dune restoration is a common method of increasing coastal resilience. A dune restoration program was initiated by the City of South Padre Island, TX in 2010 consisting primarily of plantings of Sea Oats, Uniola paniculata, and Bitter Panicum, Panicum amarum and has continued approximately annually thereafter. These restoration efforts were evaluated in this study by comparing dune ecological structure and function among reference sites and restoration plots ranging in age from 2 to 5 years. Plant and animal communities were examined using a combination of quadrat sampling, funnel traps, pit-falls and sweep nets. Soil organic content and soil electric …
Characterizing Mesophotic Reef Fish Communities At Five South Texas Relic Coral-Algal Banks, Linda Marie Jordan
Characterizing Mesophotic Reef Fish Communities At Five South Texas Relic Coral-Algal Banks, Linda Marie Jordan
Theses and Dissertations
The South Texas Banks are a mesophotic coral ecosystem (30-150m deep). Understanding the community structure, biodiversity and, geographic connectivity of the South Texas Banks is essential with increasing threats from climate change, ocean acidification, invasive species, and pollution. In this study, a remotely operated vehicle (ROV) was used to examine the fish communities at five of the South Texas Banks: Big Adam, Hospital, Mysterious, North Hospital, and Southern. Reef fish were identified to the lowest possible taxon and enumerated from ROV transect video footage. A total of 3,838 demersal and pelagic fishes were recorded representing 61 species in 22 families …
Relationships Between Texas Tortoise Carapace Length, Home Range Size, And Habitat Selection At Sites With Invasive Grass, Kiley V. Briggs
Relationships Between Texas Tortoise Carapace Length, Home Range Size, And Habitat Selection At Sites With Invasive Grass, Kiley V. Briggs
Theses and Dissertations
Invasive grasses in south Texas have the potential to negatively impact the threatened Texas tortoise (Gopherus berlandieri) by reducing the availability of preferred foods (forbs) and may cause tortoises to travel farther, lead to reduced carapace length, and reduce the availability of refugia from heat stress. I used compositional analysis, regression, and ANOVA to explore relationships between invasive grasses and habitat use, home range size, and carapace length, as well as compared daily maximum temperatures between tussocks of an invasive and native grass. Forbs were ranked higher in use over invasive grasses in compositional analysis, but not strongly so (p …
Characterizing Benthic Invertebrate Communities At Five South Texas Banks, Maria T. Cooksey
Characterizing Benthic Invertebrate Communities At Five South Texas Banks, Maria T. Cooksey
Theses and Dissertations
On the continental shelf off the coast of South Texas lie a series of hardbottom structures known as the South Texas Banks, which provide critical habitat for benthic organisms and pelagic fish species. The depth of the banks, a persistent nepheloid layer, and strong currents have hindered efforts to collect quantitative data on what inhabits the rocky outcrops and relic coral-algal reefs. Using a remotely operated vehicle, video data from five of the banks were collected in order to characterize the benthic communities. Southern and North Hospital Banks were found to be the most diverse of the studied South Texas …
Apoptotic And Necrotizing Mechanisms Of Recombinant Panton-Valentine Leukocidin In Thp1 Monocytes., Heriberto Deleon Iii
Apoptotic And Necrotizing Mechanisms Of Recombinant Panton-Valentine Leukocidin In Thp1 Monocytes., Heriberto Deleon Iii
Theses and Dissertations
The Panton-Valentine Leukocidin (PVL) is a highly specialized bacterial exotoxin produced by Staphylococcus aureus. The increased degree of invasiveness of community associated methicillin resistant Staphylococcus aureus (CAMRSA) has been attributed to the relatively high rates of PVL produced by the pathogen, thus increasing pathogenicity and virulence. The increased rates of PVL encoding CAMRSA infections have been correlated with increased rates of necrotizing fasciitis, invasive osteomyelitis and invasive necrotizing pneumococcal infections. Previous research as revealed that PVL has the ability to induce apoptosis at low concentration (5nM-10nM) and necrosis (50-100nM) at high concentrations, with little detail on the mechanism of initiation. …
Jatropha Curcas Protoplast Isolation And Inhibitory Effects Of Culture, Christopher S. Lukaszewski
Jatropha Curcas Protoplast Isolation And Inhibitory Effects Of Culture, Christopher S. Lukaszewski
Theses and Dissertations
Improvement on the sub-tropical plant Jatropha curcas may increase the use of this drought tolerant oilseed crop for the production of biodiesel. One of the methods for enhancing a species is through genetic manipulation of the protoplast. Isolating protoplasts is challenging and culturing has many obstacles similar to those seen in tissue culture, such as oxidative browning. Successful isolation of J. curcas leaf protoplasts resulted in an average of 3.23 x 106 viable protoplasts/mL. However, protoplasts diminished within 2 days after culturing. A review of the potential solutions used for overcoming the inhibitory effects of culture may reveal further insight …