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Full-Text Articles in Life Sciences

Abundance And Size Of Sand Crabs, Lepidopa Benedicti (Decapoda: Albuneidae), In Southern Texas, Jessica H. Murph, Zen Faulkes Dec 2013

Abundance And Size Of Sand Crabs, Lepidopa Benedicti (Decapoda: Albuneidae), In Southern Texas, Jessica H. Murph, Zen Faulkes

Biology Faculty Publications and Presentations

Albuneid sand crabs are found in sandy beaches around the world, but little is known about the basic biology of any species in the family. We sampled sand crabs, Lepidopa benedicti, for 2 years at South Padre Island, Texas, at two locations: one developed site near the town, where recreational use is high and one undeveloped site away from the town, where recreational use is lower. We hypothesized that sand crabs would be less abundant and smaller at the developed site than at the undeveloped one. Densities were highest in summer and lowest in winter but did not differ between …


Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez Dec 2013

Distribution And Abundance Of Anopheles Spp. In The Lower Rio Grande Valley, South Texas, Norma Hermelinda Martinez

Theses and Dissertations - UTB/UTPA

This study investigated the relationship between Anopheles abundance, collection sites and environmental variables in the Lower Rio Grande Valley, South Texas. In addition, species composition in the Lower Rio Grande Valley was determined in 2011. A total of 6772 female mosquitoes were identified to six genera and 27 species. The most prevalent genera collected were Culex (53.9%), Ochlerotatus (25.6%) and Aedes (13.6%). Anopheles mosquitoes were collected using resting boxes during summer 2012 at multiple locations along the Lower Rio Grande Valley. ArcGIS was used to identify land cover characteristics and nearest water sources at mosquito collection sites. Estero Llano Grande …


A Survey Of Heavy Metals In Water, Soil And The Surrounding Plants In The Lower Rio Grande Valley, Erving W. Morelius Dec 2013

A Survey Of Heavy Metals In Water, Soil And The Surrounding Plants In The Lower Rio Grande Valley, Erving W. Morelius

Theses and Dissertations - UTB/UTPA

Heavy metal pollution of the environment in recent years has become a major issue of importance for both human and environmental health. Samples were investigated for the potential pollution of the area as it is a vital produce producing area. During the study plant, soil and water samples were collected from the Donna Reservoir and Canal System to test the concentration of various heavy metals. The heavy metals tested included both potentially toxic and micronutrients in the samples which included arsenic, cadmium, chromium, copper, iron, lead, nickel and sulfur. During the study, a sixty day sampling period was used to …


Decomposition Patterns And Nitrogen Dynamics Of Black Mangrove (Avicennia Germinans)Leaf Litter In Disturbed Estuaries Linked To The Lower Laguna Madre, Texas, Mario Alberto Marquez Nov 2013

Decomposition Patterns And Nitrogen Dynamics Of Black Mangrove (Avicennia Germinans)Leaf Litter In Disturbed Estuaries Linked To The Lower Laguna Madre, Texas, Mario Alberto Marquez

Theses and Dissertations - UTB/UTPA

Estuaries are among the most productive aquatic systems in the world but are subject to both anthropogenic and natural disturbances. With increasing environmental concerns, efforts have become commonplace in assessing the status and trends of environmental conditions. In this study, an assessment of ecosystem status of various estuaries affected by different disturbances, was attempted through the examination of key functional processes such as leaf litter decomposition and nutrient dynamics during decay. Three estuaries located along the Brownsville Ship Channel near the southern terminus of the Lower Laguna Madre in Texas were studied. The overlying goal of this study was to …


Getting To Evo-Devo: Concepts And Challenges For Students Learning Evolutionary Developmental Biology, Anna Hiatt, Gregory K. Davis, Caleb Trujillo, Mark Terry, Donald P. French, Rebecca M. Price, Kathryn E. Perez, Diane Ebert-May Sep 2013

Getting To Evo-Devo: Concepts And Challenges For Students Learning Evolutionary Developmental Biology, Anna Hiatt, Gregory K. Davis, Caleb Trujillo, Mark Terry, Donald P. French, Rebecca M. Price, Kathryn E. Perez, Diane Ebert-May

Biology Faculty Publications and Presentations

In this study we used surveys of evo-devo experts to identify the core concepts of evo-devo and outline an underlying conceptual framework. We also use interviews and surveys of conceptual difficulties with these concepts.

To examine how well biology majors have achieved the necessary foundation in evolution, numerous studies have examined how students learn natural selection. However, no studies to date have examined how students learn developmental aspects of evolution (evo-devo). Although evo-devo plays an increasing role in undergraduate biology curricula, we find that instruction often addresses development cursorily, with most of the treatment embedded within instruction on evolution. Based …


Thorns Of Native Lower Rio Grande Valley Plants Are Colonized By Potentially Pathogenic Bacteria, Felicia A. Charles Aug 2013

Thorns Of Native Lower Rio Grande Valley Plants Are Colonized By Potentially Pathogenic Bacteria, Felicia A. Charles

Theses and Dissertations - UTB/UTPA

Epiphytic pathogenic bacteria on the thorns of native LRGV plants may provide a defense mechanism for the plants. To test this, plant thorns were collected from LRGV plant species and aerobic and anaerobic bacteria were isolated in thioglycollate medium. Tests were performed to characterize the bacterial cultures. The 16S rRNA gene was sequenced to allow for species identification. Sixty-nine bacterial cultures were isolated, including gram-positive and gram-negative cell types. All utilized a variety of carbon sources for nutrients and 23% of isolates displayed hemolysis. Bacterial identification included members of the genus Bacillus, Pseudomonas, Serratia, and others. Most were opportunistic pathogens. …


Examination Of Dietary Habits And Fruit And Vegetable Intake In A Chronic Disease Program, Qian Kuang Aug 2013

Examination Of Dietary Habits And Fruit And Vegetable Intake In A Chronic Disease Program, Qian Kuang

Theses and Dissertations - UTB/UTPA

The AHB program is a chronic disease prevention program which provides resources for community health centers along the U.S.-Mexico border. Healthy dietary habits and fruit/ vegetable intake play important roles in maintaining human health. Eight factors were used to evaluate the success of the AHB program. Another twenty factors were considered to predict dietary habits and fruit/vegetable intake status. Chi-square and multinomial logistic regression were used to study their correlation. Results from analysis showed that factors like birth country, employment, diabetes, baseline HbA1c, limited by problems, overall program quality, group, and program duration were correlated to the dietary habits, and …


Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza Jul 2013

Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza

Theses and Dissertations - UTB/UTPA

To evaluate metal tolerance conferred by the overexpression of Metal Tolerance Protein 1 (MTP1) in transgenic non-accumulator plants such as Arabidopsis thaliana, a model system was developed in Saccharomyces cerevisiae containing either SfMTP1 cDNA, from the metal tolerant plant Streptanthus farnsworthianus, or SpMTP1 cDNA, from the hyperaccumulator Streptanthus polygaloides. Nonquantitative RT-PCR showed constitutive expression of MTP1 in both plant species. Alignment of SfMTP1 and SpMTP1 protein sequences shows a gap in SpMTP1 in a variable histidine region known to affect metal transport. Disk assays revealed SfMTP1 cDNA imparted greater Ni tolerance to yeast than SpMTP1 cDNA; however, SpMTP1 showed higher …


Biochemical, Nutrient And Inhibitory Characteristics Of Streptomyces Cultured From A Hypersaline Estuary, The Laguna Madre (Texas), Luis E. Espinoza, Anita L. Davelos Baines, Kristine L. Lowe May 2013

Biochemical, Nutrient And Inhibitory Characteristics Of Streptomyces Cultured From A Hypersaline Estuary, The Laguna Madre (Texas), Luis E. Espinoza, Anita L. Davelos Baines, Kristine L. Lowe

Biology Faculty Publications and Presentations

Streptomyces are common soil bacteria that produce secondary metabolites, including several antibiotics; however, the characteristics of marine Streptomyces are largely unknown. Sediment samples were taken from 3 sites in the Laguna Madre to isolate marine Streptomyces. Sediment was diluted, spread onto synthetic seawater media to estimate the total bacterial density of the samples and spread onto starch casein agar to isolate Streptomyces. Isolated Streptomyces were tested for salinity tolerance and optimal growth pH. Isolates were assayed using API 20E® test strips and BIOLOG™ plates to construct biochemical profiles and assess nutrient utilization abilities of the bacteria, respectively. Individual Streptomyces were …


Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia May 2013

Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia

Theses and Dissertations - UTB/UTPA

Kleberg bluestem (Dichanthium annulatum) is an invasive grass species native to Africa but now found in southern United States, Mexico, and other tropical and subtropical countries throughout the world. Using the modeling software MaxEnt, climatic variables from WorldClim, the Intergovernmental Panel on Climate Change (IPCC) scenario A1B, and two General Circulatory Models: the Canadian model (Canadian Centre for Climate Modelling and Analysis or CCCMA), and the Australian model (Commonwealth Scientific and Industrial Research Organisation or CSIRO), several models were developed to determine the possible implications of climatic change on the suitable habitat for D. annulatum, in the year 2050. Models …


The Extracellular Polysaccharide Pel Makes The Attachment Of P. Aeruginosa To Surfaces Symmetric And Short-Ranged, Benjamin J. Cooley, Travis W. Thatcher, Sara M. Hashmi, Guillaume L'Her, Daniel A. Hurwitz, Daniele Provenzano, Ahmed Touhami, Vernita D. Gordon Apr 2013

The Extracellular Polysaccharide Pel Makes The Attachment Of P. Aeruginosa To Surfaces Symmetric And Short-Ranged, Benjamin J. Cooley, Travis W. Thatcher, Sara M. Hashmi, Guillaume L'Her, Daniel A. Hurwitz, Daniele Provenzano, Ahmed Touhami, Vernita D. Gordon

Biology Faculty Publications and Presentations

Biofilms are surface-mounted, multicellular communities of microbes. Biofilms are often associated with chronic infections that resist treatment, evade the immune system, and damage host tissue. An essential characteristic of the biofilm state is that constituent organisms are bound in a polymeric matrix. This matrix gives the system spatial structure and clusters bacteria near each other, facilitating intercellular interactions. The Pseudomonas aeruginosa strain PAO1 is widely studied as a model biofilm-forming organism. The polymeric matrix of PAO1 biofilms is dominated by two bacteria-produced extracellular polymers, Pel and Psl. We use a combination of optical and atomic force microscopy to examine the …


Arthropod Abundance And Diversity In Street Trees Of South Texas, Usa, Alexis Racelis, Ann T. Vacek, Carol Goolsby, John Brush, John A. Goolsby Jan 2013

Arthropod Abundance And Diversity In Street Trees Of South Texas, Usa, Alexis Racelis, Ann T. Vacek, Carol Goolsby, John Brush, John A. Goolsby

Biology Faculty Publications and Presentations

In urban areas, street trees provide a variety of ecological services, including biodiversity conservation. In this study we examined arthropod diversity on native and non-native street trees sampled during the fall of 2010 and spring of 2011 in McAllen, Texas, one of the most rapidly growing urban areas in the country. Eighty-eight street trees were sampled by removing arthropods from the lower canopy foliage using a hand held vacuum. Arthropods were collected into nylon bags, identified to order, and counted by morphospecies. Overall, street trees supported a significant and diverse population of arthropods: a total of 1,971 arthropods were collected, …


Avifauna Of The Mache Chindul Ecological Reserve, Northwest Ecuador, Luis Carrasco, Karl S. Berg, Jennifer Litz, Andrew Cook, Jordan Karubian Jan 2013

Avifauna Of The Mache Chindul Ecological Reserve, Northwest Ecuador, Luis Carrasco, Karl S. Berg, Jennifer Litz, Andrew Cook, Jordan Karubian

Biology Faculty Publications and Presentations

We report on the avifauna of the 120,000 ha Mache Chindul Ecological Reserve (REMACH), northwest Ecuador. The study area is located in a poorly studied transition zone between three major Neotropical biogeographic regions-the Chocó, Tumbesian, and Tropical Andes-each of which contains exceptional diversity and endemism in birds and other organisms. We collected data from 1998–99 and 2004–11 from the Bilsa Biological Station (a 3500 ha private reserve) and several farms, forest fragments, and communities distributed across the central portion of REMACH using observations (aural and visual), audio recordings, mist netting, point counts and photographs. We recorded 360 species of bird …


Opportunistic Pathogenic Bacteria Colonize Thorns Of Native Rio Grande Valley Plants, Felicia A. Charles, Sergio Cepeda, J. Andrew Mcdonald, Kristine L. Lowe Jan 2013

Opportunistic Pathogenic Bacteria Colonize Thorns Of Native Rio Grande Valley Plants, Felicia A. Charles, Sergio Cepeda, J. Andrew Mcdonald, Kristine L. Lowe

Biology Faculty Publications and Presentations

Thorns serve as mechanical defenses of plants against herbivory. However, plant thorns harbor microorganisms that are potentially pathogenic. These pathogens may be transferred to herbivores and other animals and provide an additional defense for the plants. Thorns from 5 plant species native to the Rio Grande Valley of South Texas were collected and used to isolate bacteria colonizing the thorn surface. Thorns, leaves and stems of plants were visualized using Scanning Electron Microscopy (SEM) to observe any bacteria on the plant surface. Isolated bacteria were tested for their ability to grow in aerobic versus anaerobic environments, to produce hemolysis, carbon …


The Evodevoci: A Concept Inventory For Gauging Students’ Understanding Of Evolutionary Developmental Biology, Kathryn E. Perez, Anna Hiatt, Gregory K. Davis, Caleb Trujillo, Donald P. French, Mark Terry, Rebecca M. Price Jan 2013

The Evodevoci: A Concept Inventory For Gauging Students’ Understanding Of Evolutionary Developmental Biology, Kathryn E. Perez, Anna Hiatt, Gregory K. Davis, Caleb Trujillo, Donald P. French, Mark Terry, Rebecca M. Price

Biology Faculty Publications and Presentations

The American Association for the Advancement of Science 2011 report Vision and Change in Undergraduate Biology Education encourages the teaching of developmental biology as an important part of teaching evolution. Recently, however, we found that biology majors often lack the developmental knowledge needed to understand evolutionary developmental biology, or “evo-devo.” To assist in efforts to improve evo-devo instruction among undergraduate biology majors, we designed a concept inventory (CI) for evolutionary developmental biology, the EvoDevoCI. The CI measures student understanding of six core evo-devo concepts using four scenarios and 11 multiple-choice items, all inspired by authentic scientific examples. Distracters were designed …


Mitigating Predatory Ants Promotes Establishment Of Biological Control Of Arundo By Arundo Scale In The Cattle Fever Tick Quarantine Zone, A. Velez-Bonner, W. L. A. Osbrink, D. W. Thomas, Kenneth R. Summy, A. T. Showler, A. Perez De Leon, John A. Goolsby Jan 2013

Mitigating Predatory Ants Promotes Establishment Of Biological Control Of Arundo By Arundo Scale In The Cattle Fever Tick Quarantine Zone, A. Velez-Bonner, W. L. A. Osbrink, D. W. Thomas, Kenneth R. Summy, A. T. Showler, A. Perez De Leon, John A. Goolsby

Biology Faculty Publications and Presentations

Ant collection, identification, and control experiments were conducted to improve the establishment of the arundo scale, Rhizaspidiotus donacis, a biological control agent of Arundo donax, an invasive weed in the riparian habitats along the Rio Grande in Texas. Observational studies indicated R. donacis immatures are preyed upon by a variety of predator insects, especially ants. A survey of the principle ant species was made at sites along the Rio Grande with Arundo donax to help direct biological control strategies. We conclude that uses of ant baits can effectively control the common ant species found in these habitats and improve the …


Factors Shaping The Ontogeny Of Vocal Signals In A Wild Parrot, Karl S. Berg, Steven R. Beissinger, Jack W. Bradbury Jan 2013

Factors Shaping The Ontogeny Of Vocal Signals In A Wild Parrot, Karl S. Berg, Steven R. Beissinger, Jack W. Bradbury

Biology Faculty Publications and Presentations

Parrots rely heavily on vocal signals to maintain their social and mobile lifestyles. We studied vocal ontogeny in nests of wild green-rumped parrotlets (Forpus passerinus) in Venezuela. We identified three successive phases of vocal signaling that corresponded closely to three independently derived phases of physiological development. For each ontogenetic phase, we characterized the relative importance of anatomical constraints, motor skills necessary for responding to specific contexts of the immediate environment, and the learning of signals that are necessary for adult forms of communication. We observed shifts in the relative importance of these three factors as individuals progressed from …