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University of Texas Rio Grande Valley

2017

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Articles 1 - 30 of 61

Full-Text Articles in Life Sciences

Geographic Variation In Juniperus Drupacea: Dna Sequencing And Volatile Leaf Oils: Further Evidence Of Putative Pleistocene Genetic Isolation Between Europe And Asia, Robert P. Adams, Adam Boratynski, Magda Dou Dagher-Kharrat, Hagar V. Leschner, Tuğrul Mataraci, Andrea E. Schwarzbach Dec 2017

Geographic Variation In Juniperus Drupacea: Dna Sequencing And Volatile Leaf Oils: Further Evidence Of Putative Pleistocene Genetic Isolation Between Europe And Asia, Robert P. Adams, Adam Boratynski, Magda Dou Dagher-Kharrat, Hagar V. Leschner, Tuğrul Mataraci, Andrea E. Schwarzbach

Health & Biomedical Sciences Faculty Publications and Presentations

Recently, Sobierajska et al. (2016), using nSSR and morphology, showed that Juniperus drupacea exhibited differentiation between Greece and Turkey/ Lebanon, suggestive of Pleistocene genetic isolation. Here, we report that leaf terpenoids and DNA sequence data support their hypothesis by confirming differentiation between Greece and Turkey/ Lebanon/ Israel. The leaf oils of the Turkey/ Lebanon plants contained one unique terpene (trans-verbenol, 0.1-1.4%) that was absent in the Greece plants. The Greece oil contained three terpenes not found in the Lebanon/ Turkey plants: (ar)-curcumene (2.2%), β-alaskene (0.3%) and α-alaskene (0.4%). Four other terpenes were in higher concentration in the Greece oils: camphene …


Functional Predictions Of Microbial Communities In Soil As Affected By Long‐Term Tillage Practices, Janani Hariharan, Aditi Sengupta, Parwinder Grewal, Warren A. Dick Dec 2017

Functional Predictions Of Microbial Communities In Soil As Affected By Long‐Term Tillage Practices, Janani Hariharan, Aditi Sengupta, Parwinder Grewal, Warren A. Dick

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Core Ideas

  • Microbial function is important but difficult to assess in soil.
  • An omics‐driven tool, PICRUSt, was used to characterize functions of soil microbial communities.
  • No‐tillage compared with plow tillage was functionally enriched for most nutrient cycles.
  • Many other functions integral to soil health can be explored by the PICRUSt omics approach.

Soil microbial communities affect the soil's biological, chemical, and physical properties, but there is still a knowledge gap regarding the long‐term impact of tillage practices on soil microbial dynamics. Additionally, the accurate identification of belowground microbial functions is a topic of active interest. In this study, microbial community …


Gastrin Induces Nuclear Export And Proteasomal Degradation Of Menin In Enteric Glial Cells, Sinju Sundaresan, Cameron A. Meininger, Anthony J. Kang, Amanda L. Photenhauer, Michael M. Hayes, Nirakar Sahoo, Jolanda Lindenberg, Jolanta Grembecka, Tomasz Cierpicki, Lin Ding Dec 2017

Gastrin Induces Nuclear Export And Proteasomal Degradation Of Menin In Enteric Glial Cells, Sinju Sundaresan, Cameron A. Meininger, Anthony J. Kang, Amanda L. Photenhauer, Michael M. Hayes, Nirakar Sahoo, Jolanda Lindenberg, Jolanta Grembecka, Tomasz Cierpicki, Lin Ding

Biology Faculty Publications and Presentations

Background & aims: The multiple endocrine neoplasia, type 1 (MEN1) locus encodes the nuclear protein and tumor suppressor menin. MEN1 mutations frequently cause neuroendocrine tumors such as gastrinomas, characterized by their predominant duodenal location and local metastasis at time of diagnosis. Diffuse gastrin cell hyperplasia precedes the appearance of MEN1 gastrinomas, which develop within submucosal Brunner's glands. We investigated how menin regulates expression of the gastrin gene and induces generation of submucosal gastrin-expressing cell hyperplasia.

Methods: Primary enteric glial cultures were generated from the VillinCre:Men1FL/FL:Sst-/- mice or C57BL/6 mice (controls), with or without inhibition of gastric acid by omeprazole. Primary …


Morganella Morganii (Enterobacteriales: Enterobacteriaceae) Is A Lethal Pathogen Of Mexican Fruit Fly (Diptera: Tephritidae) Larvae, Bacilio Salas, Hugh E. Conway, Erin Schuenzel, Kristen Hopperstad, Christopher Vitek, Don C. Vacek Dec 2017

Morganella Morganii (Enterobacteriales: Enterobacteriaceae) Is A Lethal Pathogen Of Mexican Fruit Fly (Diptera: Tephritidae) Larvae, Bacilio Salas, Hugh E. Conway, Erin Schuenzel, Kristen Hopperstad, Christopher Vitek, Don C. Vacek

Biology Faculty Publications and Presentations

Tephritid pests, such as the Mexican fruit fly, Anastrepha ludens (Loew), represent a major threat to fruit production worldwide. In order to control these pests, sterile insect technique is used to suppress and eradicate wild populations. For this control method to be successful, hundreds of millions of flies must be produced weekly in mass rearing facilities. The large quantity of artificial diet and close proximity of flies at various life stages allows bacteria from family Enterobacteriaceae, Bacillaceae, Pseudomonadaceae, and others to multiply and spread more easily. In this study, bacteria with a possible pathogenic effect were isolated from Mexican fruit …


The Acute Effects Of Resistance Exercise With Blood Flow Restriction Versus Traditional Resistance Exercise On Arterial Compliance And Energy Expenditure In Recreationally Active Males And Females, Danny D. Dominguez Dec 2017

The Acute Effects Of Resistance Exercise With Blood Flow Restriction Versus Traditional Resistance Exercise On Arterial Compliance And Energy Expenditure In Recreationally Active Males And Females, Danny D. Dominguez

Theses and Dissertations

PURPOSE: The aim of this study was to investigate the acute effects of various intensities of volume matched resistance exercise with blood flow restriction (BFR) and traditional resistance exercise on hemodynamic variables, arterial compliance, oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (RER), and energy expenditure (EE) during exercise and after exercise.

RESULTS: Significant condition main effects (p < 0.05) were found for RPE, HR, crPWV, fdPWV, LAE, SAE, TVI, RER during and postexercise. BFR25 cause greater increases in RPE and HR. BFR50 caused marked increases in SAE, crPWV, and fdPWV.

CONCLUSION: All BFR and traditional exercise conditions found no significant differences in EE, VCO2, and VO2. The lack of differences is likely due to time of protocol. Further protocols should implement greater time of exercise, as BFR had increased hemodynamic …


Utilizing Accelerometer Telemetry Tags To Compare Red Snapper (Lutjanus Campechanus) Behavior On Artificial And Natural Reefs, Ethan T. Getz Dec 2017

Utilizing Accelerometer Telemetry Tags To Compare Red Snapper (Lutjanus Campechanus) Behavior On Artificial And Natural Reefs, Ethan T. Getz

Theses and Dissertations

The Texas Parks and Wildlife Department Artificial Reef Program has deployed over 2,800 hectares of reefing area composed of petroleum platforms, steel vessels, and concrete. Artificial reefs have been shown to support many important reef fishes such as red snapper (Lutjanus campechanus), however, few studies have compared fish behavior on artificial reefs and natural habitats. We examined activity levels, behavioral patterns and habitat preferences of red snapper over natural reefs, oil platforms and submerged ships. Telemetry tags (Sonotronics model MTT) with tri-axial acceleration range, average depth, and average temperature were programmed to optimize data collection and tag life. …


Genetic Diversity Of Kemp's Ridley (Lepidochelys Kempii) Sea Turtles On South Padre Island, Texas, Hilary R. Frandsen Dec 2017

Genetic Diversity Of Kemp's Ridley (Lepidochelys Kempii) Sea Turtles On South Padre Island, Texas, Hilary R. Frandsen

Theses and Dissertations

In 2010, researchers observed an abrupt decline in nesting numbers of the Kemp’s ridley following 35 years of positive growth. In wake of this halt, and subsequent lowered nesting averages, evaluation of the genetic diversity of remaining individuals is relevant to investigate the plausibility of a genetic bottleneck, and determine the reproductive stability of the Kemp’s ridley.

Here, I evaluate the genetic diversity within a sampling of the Kemp’s ridleys on South Padre Island using two methods: targeting the mitochondrial control region and targeting the complete mitochondrial genome. Opportunistic samples were donated from juvenile ridleys on the East coast, and …


Phylogeography Of An Estuarian Calanoid Copepod; Acartia Tonsa In The Texas Gulf Of Mexico, Nicole J. Figueroa Dec 2017

Phylogeography Of An Estuarian Calanoid Copepod; Acartia Tonsa In The Texas Gulf Of Mexico, Nicole J. Figueroa

Theses and Dissertations

The calanoid copepod, Acartia tonsa is one of the most abundant and well-studied estuarian species. However, the idea that this cosmopolitan species has unrestricted dispersal and high gene flow has been challenged. In this study, a more holistic picture of the phylogeography of A. tonsa was developed using the mitochondrial gene cytochrome oxidase one (mtCOI). Multiple new lineages were found in the Texas Gulf of Mexico that are basal to Northeastern Atlantic lineages. Connectivity was also observed between Brazil and the Texas Gulf of Mexico. The revised phylogeny shows a clear pattern of cryptic speciation as the species made a …


Effect Of Land Use Change On South Texas Bats, Katharine Leigh Jones Dec 2017

Effect Of Land Use Change On South Texas Bats, Katharine Leigh Jones

Theses and Dissertations

Bats were acoustically recorded in South Texas over the summer of 2017. Nine species of bats were recorded and identified.


Foxo3 Regulation Of Stem Cell Markers Oct4 And Sox2 In Pten-Null Glioblastomas, Eduardo Martinez Dec 2017

Foxo3 Regulation Of Stem Cell Markers Oct4 And Sox2 In Pten-Null Glioblastomas, Eduardo Martinez

Theses and Dissertations

The PI3K pathway controls many cellular processes such as cell growth, survival, metabolism, apoptosis, and differentiation. Canonically, PI3K activates AKT leading to subsequent nuclear exportation of FOXO transcription factors. Dysregulation of the PI3K pathway is a hallmark in many cancers and often is attributable to a null mutation in PTEN. PTEN is a phosphatase that reverses the reactions catalyzed by PI3K. Loss of PTEN leads to constitutive inactivation of tumor suppressor FOXO proteins. However, there is increasing evidence that FOXO may still reside and promote transcriptional activity in the nucleus despite high PI3K output within certain advance cancers and …


Ph Effect On The Formation Of Thm And Haa Disinfection Byproducts And Potential Control Strategies For Food Processing, Yen-Con Hung, Brian W. Waters, Veerachandra K. Yemmireddy, Ching-Hua Huang Dec 2017

Ph Effect On The Formation Of Thm And Haa Disinfection Byproducts And Potential Control Strategies For Food Processing, Yen-Con Hung, Brian W. Waters, Veerachandra K. Yemmireddy, Ching-Hua Huang

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Chlorine-based sanitizers have seen wide spread use in food sanitation. The reaction of chlorine species with organic matter is a concern for two reasons. Available chlorine can be “used up” by organic compounds resulting in a lower amount of chlorine available for disinfection. Another concern is that some forms of chlorine can react with some organic compounds to form toxic halogenated disinfection byproducts (DBPs). Many studies have been conducted to evaluate the role of hypochlorous acid (HOCl) and hypochlorite ion (OCl−) in the production of DBPs with a particular interest in the production of trihalomethanes (THMs) and haloacetic acids (HAAs). …


Co-Independent Modification Of K+ Channels By Tricarbonyldichlororuthenium(Ii) Dimer (Corm-2), Guido Gessner, Nirakar Sahoo, Sandip M. Swain, Gianna Hirth, Roland Schönherr, Ralf Mede, Matthias Westerhausen, Hans Henning Brewitz, Pascal Heimer, Diana Imhof Nov 2017

Co-Independent Modification Of K+ Channels By Tricarbonyldichlororuthenium(Ii) Dimer (Corm-2), Guido Gessner, Nirakar Sahoo, Sandip M. Swain, Gianna Hirth, Roland Schönherr, Ralf Mede, Matthias Westerhausen, Hans Henning Brewitz, Pascal Heimer, Diana Imhof

Biology Faculty Publications and Presentations

Although toxic when inhaled in high concentrations, the gas carbon monoxide (CO) is endogenously produced in mammals, and various beneficial effects are reported. For potential medicinal applications and studying the molecular processes underlying the pharmacological action of CO, so-called CO-releasing molecules (CORMs), such as tricabonyldichlororuthenium(II) dimer (CORM-2), have been developed and widely used. Yet, it is not readily discriminated whether an observed effect of a CORM is caused by the released CO gas, the CORM itself, or any of its intermediate or final breakdown products. Focusing on Ca2+- and voltage-dependent K+ channels (KCa1.1) and voltage-gated K+ channels (Kv1.5, Kv11.1) relevant …


A Metadata Reporting Framework (Frames) For Synthesis Of Ecohydrological Observations, Danielle S. Christianson, Charuleka Varadharajan, Bradley O. Christoffersen, Matteo Detto, Boris Faybishenko, Bruno O. Gimenez, Val Hendrix, Kolby J. Jardine, Robinson Negron-Juarez, Gilberto Z. Pastorello Nov 2017

A Metadata Reporting Framework (Frames) For Synthesis Of Ecohydrological Observations, Danielle S. Christianson, Charuleka Varadharajan, Bradley O. Christoffersen, Matteo Detto, Boris Faybishenko, Bruno O. Gimenez, Val Hendrix, Kolby J. Jardine, Robinson Negron-Juarez, Gilberto Z. Pastorello

Biology Faculty Publications and Presentations

Metadata describe the ancillary information needed for data preservation and independent interpretation, comparison across heterogeneous datasets, and quality assessment and quality control (QA/QC). Environmental observations are vastly diverse in type and structure, can be taken across a wide range of spatiotemporal scales in a variety of measurement settings and approaches, and saved in multiple formats. Thus, well-organized, consistent metadata are required to produce usable data products from diverse environmental observations collected across field sites. However, existing metadata reporting protocols do not support the complex data synthesis and model-data integration needs of interdisciplinary earth system research. We developed a metadata reporting …


Validating Sidescan Sonar As A Fish Survey Tool Over Artificial Reefs, Michael A. Bollinger, Richard J. Kline Nov 2017

Validating Sidescan Sonar As A Fish Survey Tool Over Artificial Reefs, Michael A. Bollinger, Richard J. Kline

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Visual observation methods via SCUBA are commonly used to survey artificial reef fish, although conditions in the Gulf of Mexico often make surveys difficult or even dangerous for divers. In this study, sidescan sonar was used to quantify water-column fish abundance and was compared to the established visual observation methods on SCUBA over four reef sites. Calibrated intensity values measured from sidescan sonar echo returns were used to estimate fish body length and to calculate scaled biomass (g/m2 reef) from a pooled fish length–weight relationship of commonly observed reef fish in the area. Sidescan sonar methods were equivalent to SCUBA …


Capturing Species-Level Drought Responses In A Temperate Deciduous Forest Using Ratios Of Photochemical Reflectance Indices Between Sunlit And Shaded Canopies, Taehee Hwang, Hamed Gholizadeh, Daniel A. Sims, Kimberly A. Novick, Edward R. Brzostek, Richard P. Phillips, Daniel T. Roman, Scott M. Robeson, Abdullah F. Rahman Oct 2017

Capturing Species-Level Drought Responses In A Temperate Deciduous Forest Using Ratios Of Photochemical Reflectance Indices Between Sunlit And Shaded Canopies, Taehee Hwang, Hamed Gholizadeh, Daniel A. Sims, Kimberly A. Novick, Edward R. Brzostek, Richard P. Phillips, Daniel T. Roman, Scott M. Robeson, Abdullah F. Rahman

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Highlights

  • We examine capability of spectral indices to capture isohydric/anisohydric behavior.

  • We used both in-situ spectral measurements and multi-angle MODIS images.

  • Only PRI could capture species-level drought responses.

  • This study presents a step forward to directly mapping emergent isohydricity.

Abstract

To classify trees along a spectrum of isohydric to anisohydric behavior is a promising new framework for identifying tree species' sensitivities to drought stress, directly related to the vulnerability of carbon uptake of terrestrial ecosystems with increased hydroclimate variability. Trees with isohydric strategies regulate stomatal conductance to maintain stationary leaf water potential, while trees with anisohydric strategies allow leaf …


Nitrate Leaching From Sand And Pumice Geomedia Amended With Pyrogenic Carbon Materials, Jihoon Kang, Marissa Davila, Sergio Mireles, Jungseok Ho Oct 2017

Nitrate Leaching From Sand And Pumice Geomedia Amended With Pyrogenic Carbon Materials, Jihoon Kang, Marissa Davila, Sergio Mireles, Jungseok Ho

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

There is increasing interest in using pyrogenic carbon as an adsorbent for aqueous contaminants in stormwater. The objective of this study was to investigate pyrogenic carbon materials as an amendment to geomedia to reduce nitrate leaching. Batch adsorption and column experiments were conducted to evaluate the performance of a commercial activated carbon and two biochars incorporated (5% by weight) into sand and pumice columns. The batch adsorption with 50 mg L−1 of nitrate solution showed that only activated carbon resulted in a substantial adsorption for nitrate up to 41%. Tested biochars were not effective in removing aqueous nitrate and even …


Linear And Nonlinear Effects Of Temperature And Precipitation On Ecosystem Properties In Tidal Saline Wetlands, Laura C. Feher, Michael J. Osland, Kereen T. Griffith, James B. Grace, Rebecca J. Howard, Camille L. Stagg, Nicholas M. Enwright, Ken W. Krauss, Christopher A. Gabler, Richard H. Day, Kerrylee Rogers Oct 2017

Linear And Nonlinear Effects Of Temperature And Precipitation On Ecosystem Properties In Tidal Saline Wetlands, Laura C. Feher, Michael J. Osland, Kereen T. Griffith, James B. Grace, Rebecca J. Howard, Camille L. Stagg, Nicholas M. Enwright, Ken W. Krauss, Christopher A. Gabler, Richard H. Day, Kerrylee Rogers

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Climate greatly influences the structure and functioning of tidal saline wetland ecosystems. However, there is a need to better quantify the effects of climatic drivers on ecosystem properties, particularly near climate-sensitive ecological transition zones. Here, we used climate- and literature-derived ecological data from tidal saline wetlands to test hypotheses regarding the influence of climatic drivers (i.e., temperature and precipitation regimes) on the following six ecosystem properties: canopy height, biomass, productivity, decomposition, soil carbon density, and soil carbon accumulation. Our analyses quantify and elucidate linear and nonlinear effects of climatic drivers. We quantified positive linear relationships between temperature and above-ground productivity …


A Novel Diffuse Fraction-Based Two-Leaf Light Use Efficiency Model: An Application Quantifying Photosynthetic Seasonality Across 20 Ameriflux Flux Tower Sites, Hao Yan, Shao-Qiang Wang, Kai-Liang Yu, Bin Wang, Qin Yu, Gil Bohrer, Dave Billesbach, Rosvel Bracho, Abdullah F. Rahman, Herman H. Shugart Oct 2017

A Novel Diffuse Fraction-Based Two-Leaf Light Use Efficiency Model: An Application Quantifying Photosynthetic Seasonality Across 20 Ameriflux Flux Tower Sites, Hao Yan, Shao-Qiang Wang, Kai-Liang Yu, Bin Wang, Qin Yu, Gil Bohrer, Dave Billesbach, Rosvel Bracho, Abdullah F. Rahman, Herman H. Shugart

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Diffuse radiation can increase canopy light use efficiency (LUE). This creates the need to differentiate the effects of direct and diffuse radiation when simulating terrestrial gross primary production (GPP). Here, we present a novel GPP model, the diffuse-fraction-based two-leaf model (DTEC), which includes the leaf response to direct and diffuse radiation, and treats maximum LUE for shaded leaves (ɛmsh defined as a power function of the diffuse fraction (Df)) and sunlit leaves (ɛmsu defined as a constant) separately. An Amazonian rainforest site (KM67) was used to calibrate the model by simulating the linear relationship …


Filtering Out Parasites: Sand Crabs (Lepidopa Benedicti) Are Infected By More Parasites Than Sympatric Mole Crabs (Emerita Benedicti), Zen Faulkes Sep 2017

Filtering Out Parasites: Sand Crabs (Lepidopa Benedicti) Are Infected By More Parasites Than Sympatric Mole Crabs (Emerita Benedicti), Zen Faulkes

Biology Faculty Publications and Presentations

Two digging decapod crustaceans, the sand crab species Lepidopa benedicti and the mole crab species Emerita benedicti, both live in the swash zone of fine sand beaches. They were examined for two parasites that infect decapod crustaceans in the region, an unidentified nematode previously shown to infect L. benedicti, and cestode tapeworm larvae, Polypocephalus sp., previously shown to infect shrimp (Litopenaeus setiferus). Lepidopa benedicti were almost always infected with both parasite species, while E. benedicti were rarely infected with either parasite species. This difference in infection pattern suggests that tapeworms are ingested during sediment feeding in …


Climate Controls Over The Net Carbon Uptake Period And Amplitude Of Net Ecosystem Production In Temperate And Boreal Ecosystems, Zheng Fu, Paul C. Stoy, Yiqi Luo, Jiquan Chen, Jian Sun, Leonardo Montagnani, Georg Wohlfahrt, Abdullah F. Rahman, Serge Rambal, Christian Bernhofer Sep 2017

Climate Controls Over The Net Carbon Uptake Period And Amplitude Of Net Ecosystem Production In Temperate And Boreal Ecosystems, Zheng Fu, Paul C. Stoy, Yiqi Luo, Jiquan Chen, Jian Sun, Leonardo Montagnani, Georg Wohlfahrt, Abdullah F. Rahman, Serge Rambal, Christian Bernhofer

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Highlights

  • The start of net C uptake was determined by spring temperature in DBF and EF.

  • Summer precipitation determined NEPmax anomalies in DBF and GRA.

  • Climate controls annual NEP variability by regulating CUP and NEPmax.

Abstract


The seasonal and interannual variability of the terrestrial carbon cycle is regulated by the interactions of climate and ecosystem function. However, the key factors and processes determining the interannual variability of net ecosystem productivity (NEP) in different biomes are far from clear. Here, we quantified yearly anomalies of seasonal and annual NEP, net carbon uptake period (CUP), and the maximum daily NEP (NEPmax) …


N2o Emissions From California Farmlands: A Review, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Charlotte Decock, Gina Garland, Taryn Kennedy, Emma Suddick, William Horwath, Johan Six Sep 2017

N2o Emissions From California Farmlands: A Review, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Charlotte Decock, Gina Garland, Taryn Kennedy, Emma Suddick, William Horwath, Johan Six

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Of the greenhouse gases emitted from cropland, nitrous oxide (N2O) has the highest global warming potential. The state of California acknowledges that agriculture both contributes to and is affected by climate change, and in 2016 it adopted legislation to help growers reduce emissions of greenhouse gases, explicitly including N2O. Nitrous oxide emissions can vary widely due to environmental and agronomic factors with most emission estimates coming from temperate grain systems. There is, however, a dearth of emission estimates from perennial and vegetable cropping systems commonly found in California's Mediterranean climate. Therefore, emission factors (EFs) specific to California conditions are needed …


T6ss Intraspecific Competition Orchestrates Vibrio Cholerae Genotypic Diversity, Benjamin Kostiuk, Daniel Unterweger, Daniele Provenzano, Stefan Pukatzki Sep 2017

T6ss Intraspecific Competition Orchestrates Vibrio Cholerae Genotypic Diversity, Benjamin Kostiuk, Daniel Unterweger, Daniele Provenzano, Stefan Pukatzki

Biology Faculty Publications and Presentations

Vibrio cholerae is a diverse species that inhabits a wide range of environments from copepods in brackish water to the intestines of humans. In order to remain competitive, V. cholerae uses the versatile type-VI secretion system (T6SS) to secrete anti-prokaryotic and anti-eukaryotic effectors. In addition to competing with other bacterial species, V. cholerae strains also compete with one another. Some strains are able to coexist, and are referred to as belonging to the same compatibility group. Challenged by diverse competitors in various environments, different V. choleare strains secrete different combination of effectors - presumably to best suit their niche. Interestingly, …


Principal Component Regression Analysis Of Nutrition Factors And Physical Activities With Diabetes, Ke-Sheng Wang, Ying Lu, Xin Xie, Shaoqing Gong, Chun Xu, Zhanxin Sha Aug 2017

Principal Component Regression Analysis Of Nutrition Factors And Physical Activities With Diabetes, Ke-Sheng Wang, Ying Lu, Xin Xie, Shaoqing Gong, Chun Xu, Zhanxin Sha

Health & Biomedical Sciences Faculty Publications and Presentations

The associations of nutrition factors and physical activities with adult diabetes are inconsistent; while most of these factors are inter correlated. The aims of this study are to overcome the disturbance of the multicollinearity of the risk factors and examine the associations of these factors with diabetes using the principal component analysis (PCA) and regression analysis with principal component scores (PCS). Totally, 659 adults with diabetes and 2827 non-diabetic were selected from the 2012 Health Information National Trends Survey (HINTS 4, Cycle 2). PCA was utilized to deal with multicollinearity of the risk factors. Weighted univariate and multiple logistic regression …


Impact Of Salinity Change On Water Quality Variables From The Sediment Of An Artificial Lake Under Anaerobic Conditions, Tae-Hoon Kim, Jihoon Kang, Sang Hyun Kim, I-Song Choi, Kwang-Hyeon Chang, Jong Min Oh, Ki-Hyun Kim Aug 2017

Impact Of Salinity Change On Water Quality Variables From The Sediment Of An Artificial Lake Under Anaerobic Conditions, Tae-Hoon Kim, Jihoon Kang, Sang Hyun Kim, I-Song Choi, Kwang-Hyeon Chang, Jong Min Oh, Ki-Hyun Kim

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Artificial reservoirs are created by dike construction in coastal areas to secure the agricultural water supply on the west coast of South Korea. These systems are found to retain brackish characteristics until total desalination is achieved. To evaluate the effects of salinity on the organic substances released from the sediment, a laboratory water-sediment column experiment was conducted to assess associated changes in water quality variables such as the sediment oxygen demand (SOD), chemical oxygen demand (COD), and concentrations of nitrogen (N) and phosphorus (P). Under high salinity conditions, the release of N from the sediment was promoted with the enhancement …


(Re)Defining Masculinity: Creando Conciencia Y Conocimiento Sobre La Educación Through Food, Jesus Aaron Sierra Aug 2017

(Re)Defining Masculinity: Creando Conciencia Y Conocimiento Sobre La Educación Through Food, Jesus Aaron Sierra

Theses and Dissertations

This thesis describes how food, culture, and class have shaped how I have acculturated, negotiated and blended Mexican and American. It highlights various themes that have shaped my educational process, including, masculinity, family values, food production, service and consumption. The proximity of South Texas to the U.S.-Mexican border plays an important role in the gastronomy of the Rio Grande Valley (RGV). This is a region where people interact across race, ethnicity and culture to create different dishes and customs surrounding food. It also demonstrates how food brings people together. The methodology used in this thesis is from the autoethnographic perspective …


Linking Plant Hydraulics And Beta Diversity In Tropical Forests, Bradley O. Christoffersen, Patrick Meir, Nate G. Mcdowell Jul 2017

Linking Plant Hydraulics And Beta Diversity In Tropical Forests, Bradley O. Christoffersen, Patrick Meir, Nate G. Mcdowell

Biology Faculty Publications and Presentations

This article is a Commentary on Cosme et al., 215: 113–125.


Removal Of Lead And Arsenic From Aqueous Solution By Biochar Produced From Locally-Sourced Biomass, Sergio I. Mireles Jul 2017

Removal Of Lead And Arsenic From Aqueous Solution By Biochar Produced From Locally-Sourced Biomass, Sergio I. Mireles

Theses and Dissertations

This study evaluated the effectiveness of four adsorbent materials, pyrolyzed corn stover, orange peel, pistachio shell, and magnetic biochar for their ability to adsorb lead (Pb) and arsenic (As III, As V) from aqueous solution. An increase in adsorption was seen as the pH of the solution increased from pH 2 to pH 6. Magnetic orange peel biochar with Fe3O4 particles precipitated on the surface of biochar was synthetized by co-precipitation and used for arsenic adsorption. Initial pH value had an influence on the adsorption behavior of As (III) and As (V). In the pH range of 2–6, As (V) …


Effectiveness Of The Flipped Classroom Model In Anatomy And Physiology Laboratory Courses At A Hispanic Serving Institution, Gerardo Sanchez Jul 2017

Effectiveness Of The Flipped Classroom Model In Anatomy And Physiology Laboratory Courses At A Hispanic Serving Institution, Gerardo Sanchez

Theses and Dissertations

A flipped laboratory model involves significant preparation by the students on lab material prior to entry to the laboratory. This allows laboratory time to be focused on active learning through experiments. The aim of this study was to observe changes in student performance through the transition from a traditional laboratory format, to a flipped format. The data showed that for both Anatomy and Physiology (I and II) laboratories a more normal distribution of grades was observed once labs were flipped and lecture grade averages increased. Chi square and analysis of variance tests showed grade changes to a statistically significant degree, …


The Effects Of A Short-Term Endurance Training Program With Blood Flow Restriction Cuffs Versus Acsm Recommended Endurance Training On Arterial Compliance And Muscular Adaptations In Recreationally Active Males, Brittany N. Esparza Jul 2017

The Effects Of A Short-Term Endurance Training Program With Blood Flow Restriction Cuffs Versus Acsm Recommended Endurance Training On Arterial Compliance And Muscular Adaptations In Recreationally Active Males, Brittany N. Esparza

Theses and Dissertations

RESULTS: Significant time and group interaction found in cardiac ejection time (p<.05). Significant condition difference between blood flow restriction (BFR) and control for heart rate (HR) max (p=.05) and maximum oxygen consumption (VO2) (p<.05). Significant time difference found in pulse wave velocity femoral to distal (p<.05). Significant repetition main effect (p<.01) for root mean square (RMS) and median frequency (MDF) of Thorstensson. Significant time and group interaction in vastus lateralis of MDF (p<.01). Significant repetition main effect for RMS and MDF ratio (p<.01) Significant time and repetition interaction in vastus lateralis of RMS ratio (p<.03)

CONCLUSION: The BFR session showed improvement in both post HR max and post VO2 in comparison to the control group. This may have been caused by increased tolerance to pain/metabolic by-products for HR and increased efficiency at extracting oxygen for VO2


Central Precocious Puberty Alters The Mammary Gland Epithelial Landscape In Female Rats, Alina M. Hamilton Jul 2017

Central Precocious Puberty Alters The Mammary Gland Epithelial Landscape In Female Rats, Alina M. Hamilton

Theses and Dissertations

Precocious puberty (PP) is a serious endocrine disorder associated with an increased risk for development of breast cancer (BC) later in life. However, the lack of a strong in vivo model has made it difficult to study this relationship. Our group has established manganese (Mn) as a non-toxic activator of the pubertal process. Recently we demonstrated that Mn-induced precocious puberty (MnPP) accelerates E2-regulated mammary gland (MG) development in prepubertal female rats, resulting in persistent proliferation and adult hyperplasia. Using this model, I demonstrate that precocious puberty alters steroidal regulation of proliferation in both the prepubertal and adult virgin MG, altering …