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Perceived Effectiveness Of E-Learning For Technology Instruction In Public Library Staff Development Programs: A Survey Based On The Technology Acceptance Model, Julia Huprich Jul 2016

Perceived Effectiveness Of E-Learning For Technology Instruction In Public Library Staff Development Programs: A Survey Based On The Technology Acceptance Model, Julia Huprich

Master of Science in Information Technology Theses

The purpose of this research study was to determine the perceived effectiveness of e-learning for staff members in public libraries. In addition, the effects of user demographics - including a user’s age and gender - were analyzed to determine if these factors impacted the perceived effectiveness of e-learning as a training delivery model.

Davis’s Technology Acceptance Model (1989) was used to develop a questionnaire related to the perceived effectiveness and value of e-learning, and a survey of public library staff members across the United States was conducted. Results of the survey showed the impact that previous e-learning experience and the …


Can Twilight Reefs Usher In A New Dawn For Depauperate Shallow Coral Reefs?, Hunter Kg Noren Jul 2016

Can Twilight Reefs Usher In A New Dawn For Depauperate Shallow Coral Reefs?, Hunter Kg Noren

HCNSO Student Theses and Dissertations

As shallow reefs continue to decline, scientists are searching for the key to their persistence; as it turns out, they may just need to look deeper. Below many shallow tropical reefs, there exist healthy and more stable mesophotic coral reef communities. The ability of these reefs to act as a refuge for declining shallow populations has garnered significant interest among the scientific community; however, the reproductive and larval aspects necessary for this to occur are unknown. This study assesses the ability of deep reefs to act as a reproductive refuge for shallow counterparts by examining gametic compatibility, viability and larval …


Using Regression-Based Effect Size Meta-Analysis To Investigate Coral Responses To Climate Change, Niklas Alexander Kornder Jul 2016

Using Regression-Based Effect Size Meta-Analysis To Investigate Coral Responses To Climate Change, Niklas Alexander Kornder

HCNSO Student Theses and Dissertations

Attempts to quantify the effects of ocean acidification and warming (OAW) on scleractinian corals provide a growing body of response measurements. However, placing empirical results into an ecological context is challenging, owing to variations that reflect both natural heterogeneity and scientific bias. This study addresses the heterogeneity of climate change induced changes in coral recruitment and calcification. To discern scientific bias and identify drivers of the remaining heterogeneity, 100 publications were analyzed using a combination of weighted mixed effects meta-regression and factorial effect size meta‑analysis. A linear model was applied to quantify the variation caused by differing stress levels across …


Soil Extracellular Enzyme Activities, Soil Carbon And Nitrogen Storage Under Nitrogen Fertilization: A Meta-Analysis, Siyang Jian, Jianwei Li, Ji Chen, Gangsheng Wang, Melanie A. Mayes, Kudjo E. Dzantor, Dafeng Hui, Yiqi Luo Jul 2016

Soil Extracellular Enzyme Activities, Soil Carbon And Nitrogen Storage Under Nitrogen Fertilization: A Meta-Analysis, Siyang Jian, Jianwei Li, Ji Chen, Gangsheng Wang, Melanie A. Mayes, Kudjo E. Dzantor, Dafeng Hui, Yiqi Luo

Agricultural and Environmental Sciences Faculty Research

Nitrogen (N) fertilization affects the rate of soil organic carbon (SOC) decomposition by regulating extracellular enzyme activities (EEA). Extracellular enzymes have not been represented in global biogeochemical models. Understanding the relationships among EEA and SOC, soil N (TN), and soil microbial biomass carbon (MBC) under N fertilization would enable modeling of the influence of EEA on SOC decomposition. Based on 65 published studies, we synthesized the activities of α-1,4-glucosidase (AG), β-1,4-glucosidase (BG), β-d-cellobiosidase (CBH), β-1,4-xylosidase (BX), β-1,4-N-acetyl-glucosaminidase (NAG), leucine amino peptidase (LAP), urease (UREA), acid phosphatase (AP), phenol oxidase (PHO), and peroxidase (PEO) in response to N fertilization. The proxy …


Monitoring And Mitigation Of Elevated Co2 Impacts Using Microalgae, Terry-Rene Wiesner Brown Jul 2016

Monitoring And Mitigation Of Elevated Co2 Impacts Using Microalgae, Terry-Rene Wiesner Brown

USF Tampa Graduate Theses and Dissertations

Climate change is arguably the greatest environmental and economic challenge of our time. There are considerable documented and projected impacts to both human and natural systems as a result of climate change. These impacts include changes in temperature, sea level, precipitation patterns, and biogeography of ecologically and economically relevant species, including pathogens. One of the main drivers of climate change is elevated levels of atmospheric carbon dioxide (CO2), a greenhouse gas. Since pre-industrial times, atmospheric CO2 levels have increased from approximately 280 ppm to over 400 ppm, as a result of fossil fuel combustion, cement production and …


Assessment Of A Mycorrhizal Fungi Application To Treat Stormwater In An Urban Bioswale, Alaina Diane Melville Jul 2016

Assessment Of A Mycorrhizal Fungi Application To Treat Stormwater In An Urban Bioswale, Alaina Diane Melville

Dissertations and Theses

This study assessed the effect of an application of mycorrhizal fungi to stormwater filter media on urban bioswale soil and stormwater in an infiltration-based bioswale aged 20 years with established vegetation. The study tested the use of commercially available general purpose biotic soil blend PermaMatrix® BSP Foundation as a treatment to enhance Earthlite™ stormwater filter media amelioration of zinc, copper, and phosphorus in an ecologically engineered structure designed to collect and infiltrate urban stormwater runoff before it entered the nearby Willamette River.

These results show that the application of PermaMatrix® BSP Foundation biotic soil amendment to Earthlite …


Evaluating The Influences Of Karst Hydrogeology On Freshwater Harmful Algal Blooms In Kentucky Lakes, Robert T. Schaefer Jul 2016

Evaluating The Influences Of Karst Hydrogeology On Freshwater Harmful Algal Blooms In Kentucky Lakes, Robert T. Schaefer

Masters Theses & Specialist Projects

A problem exists in Nolin River Lake and Rough River Lake in Kentucky, due to the increasing prevalence of cyanobacterial-based harmful algal blooms (CyanoHABs) and the threats they pose to local communities. These lakes were developed as artificial reservoirs from embankment. Further complicating the issue, the lakes are located within a heavily karstified region and there exists no plan or method currently for monitoring or managing CyanoHABs in a karst region with regard to groundwater inputs to the lake systems or their tributaries. A mixture of techniques and analysis methods was used to determine the best way to monitor and …


Thermal Analysis In A Triple-Layered Skin Structure With Embedded Vasculature, Tumor, And Gold Nanoshells, Casey O. Orndorff Jul 2016

Thermal Analysis In A Triple-Layered Skin Structure With Embedded Vasculature, Tumor, And Gold Nanoshells, Casey O. Orndorff

Doctoral Dissertations

In hyperthermia skin cancer treatment, the objective is to control laser heating of the tumor (target temperatures of 42-46 °C) so that the temperatures of the normal tissue surrounding the tumor remains low enough not to damage the normal tissue. However, obtaining accurate temperature distributions in living tissue related to hyperthermia skin cancer treatment without using an intruding sensor is a challenge. The objective of this dissertation research is to develop a mathematical model that can accurately predict the temperature distribution in the tumor region and surrounding normal tissue induced by laser irradiation. The model is based on a modified …


Providing Water For Beef Cattle In Rotational Grazing Systems, Stephen F. Higgins, Lee Moser, Kevin Laurent Jul 2016

Providing Water For Beef Cattle In Rotational Grazing Systems, Stephen F. Higgins, Lee Moser, Kevin Laurent

Agriculture and Natural Resources Publications

Water is the most essential nutrient for cattle production. Water is used in almost every bodily function, including digestion, milk production, and excretion. Given the role and function of water in relation to animal production, health, and welfare, it is critical that abundant, clean water is available in any livestock production operation. Livestock must have immediate access to water within every paddock of a rotational grazing system to realize maximum efficiency and production.


Instructional Framing And Student Learning Of Community Interactions, Nathaniel Niosco Jul 2016

Instructional Framing And Student Learning Of Community Interactions, Nathaniel Niosco

School of Natural Resources: Dissertations, Theses, and Student Research

Ecology is a broad field of science that encompasses many disciplines with large impacts in our society (AAAS, 2011; NRC, 2009). To understand the complex systems and concepts of this discipline requires a foundation of knowledge that students often gain in the classroom (Bransford, Brown, & Cocking, 2000). Helping students develop this foundation of knowledge requires an understanding of how they use surface and deep reasoning skills to understand and learn new material. In addition, using methods to teach students to transfer these skills between multiple contexts is key to expanding their ability to broadly apply knowledge. The purpose of …


Climate-Ready Agriculture: A Situation Statement For Western Australia, Robert Anthony Sudmeyer, Anne Bennett, Melanie Strawbridge Jul 2016

Climate-Ready Agriculture: A Situation Statement For Western Australia, Robert Anthony Sudmeyer, Anne Bennett, Melanie Strawbridge

Bulletins 4000 -

Projected future changes in the state’s climate will present new challenges for our producers. The Department of Agriculture and Food, Western Australia (DAFWA) continues to work with agricultural industries to lay solid foundations for an agricultural sector that has a range of response options.

This situation statement provides an assessment of how climate-ready the state’s agricultural sectors are and provides guidance for investment priorities for DAFWA for the period 2015–2020.


Clear Creek Estuary Restoration: Establishing An Ecological Monitoring Program And Baseline Conditions, Christine Butler-Minor Jul 2016

Clear Creek Estuary Restoration: Establishing An Ecological Monitoring Program And Baseline Conditions, Christine Butler-Minor

Environmental Science and Management Professional Master's Project Reports

Monitoring habitat conditions in the Clear Creek Estuary before the completion of the Bucklin Hill Bridge Project is a critical part of this ecosystem restoration planning and execution. The Clear Creek Trail Alliance (CCTA) is working with local partners to monitor the effects of the estuary restoration. In a wider effort to characterize salmonid habitat suitability of the estuary prior to the bridge replacement, CCTA would like to gather data related to water quality, beach/bank elevations, vegetation in the vicinity, and invertebrate diversity in the estuary. The development and implementation of this Clear Creek Estuary monitoring project provides an opportunity …


Costimulation Of Soil Glycosidase Activity And Soil Respiration By Nitrogen Addition, Ji Chen, Yiqi Luo, Jianwei Li, Xuhui Zhou, Junji Cao, Rui-Wu Wang, Yunqiang Wang, Shelby Shelton, Zhao Jin, Laura M. Walker, Zhaozhong Feng, Shuli Niu, Wenting Feng, Siyang Jian, Lingyan Zhou Jun 2016

Costimulation Of Soil Glycosidase Activity And Soil Respiration By Nitrogen Addition, Ji Chen, Yiqi Luo, Jianwei Li, Xuhui Zhou, Junji Cao, Rui-Wu Wang, Yunqiang Wang, Shelby Shelton, Zhao Jin, Laura M. Walker, Zhaozhong Feng, Shuli Niu, Wenting Feng, Siyang Jian, Lingyan Zhou

Agricultural and Environmental Sciences Faculty Research

Unprecedented levels of nitrogen (N) have been deposited in ecosystems over the past century, which is expected to have cascading effects on microbially mediated soil respiration (SR). Extracellular enzymes play critical roles on the degradation of soil organic matter, and measurements of their activities are potentially useful indicators of SR. The links between soil extracellular enzymatic activities (EEAs) and SR under N addition, however, have not been established. We therefore conducted a meta-analysis from 62 publications to synthesize the responses of soil EEAs and SR to elevated N. Nitrogen addition significantly increased glycosidase activity (GA) by 13.0%, α-1,4-glucosidase (AG) by …


Iron Uptake And Accumulation Is A Target Of Nickel Toxicity During The Lag Phase In Escherichia Coli, Geoffrey Tuttle Ford Jun 2016

Iron Uptake And Accumulation Is A Target Of Nickel Toxicity During The Lag Phase In Escherichia Coli, Geoffrey Tuttle Ford

Theses and Dissertations

Various transition metals are essential to all forms of life, and are only required in trace amounts. But this dependence comes as a double-edged sword. All organisms must maintain a careful intracellular quota that does not traverse outside an acceptable range. One transition metal in particular is nickel. The importance of this transition metal has been debated widely and its function varies greatly between organisms, including bacteria. However, the adverse effects caused by over exposure to this metal have been the center of much experimentation in recent years. Still, the mechanisms of nickel toxicity and the subsequent effects on cellular …


One View: Fire Fuels Regeneration In Eastern Sierra, Char Miller Jun 2016

One View: Fire Fuels Regeneration In Eastern Sierra, Char Miller

Pomona Faculty Publications and Research

Sometimes it’s the small things that can best tell big stories.

Like the Marina Fire, which currently has burned a modest 800 acres to the north of Lee Vining, threatened but did not burn any structures, and whose greatest disruption has been periodically to shut down US 395. It hardly seems worth much attention.


Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West Jun 2016

Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West

USF Tampa Graduate Theses and Dissertations

Mollusk shells contain proteins within and between the crystals of calcium carbonate. These organic molecules play an important role in biomineralization and shell function, and their stable isotope ratios of carbon and nitrogen are also thought to record important ecological information about the animal's diet and nutrient sources. These proteins can be preserved for millions of years, offering potential insight into pre-anthropogenic ecological conditions. However, shell organics in older shells are typically recovered in reduced abundances due to leaching and remaining organics are often converted from insoluble proteins to soluble, free amino acids, making them difficult to detect and recover. …


Modeling Of Soybean Under Present And Future Climates In Mozambique, Manuel António Dina Talacuece, Flávio Barbosa Justino, Rafael De Ávila Rodrigues, Milton Edgar Pereira Flores, Jéssica Garcia Nascimento, Eduardo Eduardo Santos Jun 2016

Modeling Of Soybean Under Present And Future Climates In Mozambique, Manuel António Dina Talacuece, Flávio Barbosa Justino, Rafael De Ávila Rodrigues, Milton Edgar Pereira Flores, Jéssica Garcia Nascimento, Eduardo Eduardo Santos

Daugherty Water for Food Global Institute: Faculty Publications

This study aims to calibrate and validate the generic crop model (CROPGRO-Soybean) and estimate the soybean yield, considering simulations with different sowing times for the current period (1990–2013) and future climate scenario (2014–2030). The database used came from observed data, nine climate models of CORDEX (Coordinated Regional climate Downscaling Experiment)-Africa framework and MERRA (Modern Era Retrospective-Analysis for Research and Applications) reanalysis. The calibration and validation data for the model were acquired in field experiments, carried out in the 2009/2010 and 2010/2011 growing seasons in the experimental area of the International Institute of Tropical Agriculture (IITA) in Angónia, Mozambique. The yield …


The Firece Green Fire: Vol. 7 Issue 2, Wofford College Environmental Studies Program Jun 2016

The Firece Green Fire: Vol. 7 Issue 2, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Diversity, Structure And Convergent Evolution Of The Global Sponge Microbiome, Torsten Thomas, Lucas Moitinho-Silva, Miguel Lurgi, Johannes R. Bjork, Cole Easson, Carmen Astudillo-Garcia, Julie B. Olson, Patrick M. Erwin, Susanna Lopez-Legentil, Heidi Luter, Andia Chaves Fonnegra, Rodrigo Costa, Peter J. Schupp, Laura Steindler, Dirk Erpenbeck, Jack Gilbert, Rob Knight, Gail Ackermann, Jose V. Lopez, Michael W. Taylor, Robert W. Thacker, Jose M. Montoya, Ute Hentschel, Nicole S. Webster Jun 2016

Diversity, Structure And Convergent Evolution Of The Global Sponge Microbiome, Torsten Thomas, Lucas Moitinho-Silva, Miguel Lurgi, Johannes R. Bjork, Cole Easson, Carmen Astudillo-Garcia, Julie B. Olson, Patrick M. Erwin, Susanna Lopez-Legentil, Heidi Luter, Andia Chaves Fonnegra, Rodrigo Costa, Peter J. Schupp, Laura Steindler, Dirk Erpenbeck, Jack Gilbert, Rob Knight, Gail Ackermann, Jose V. Lopez, Michael W. Taylor, Robert W. Thacker, Jose M. Montoya, Ute Hentschel, Nicole S. Webster

Marine & Environmental Sciences Faculty Articles

Sponges (phylum Porifera) are early-diverging metazoa renowned for establishing complex microbial symbioses. Here we present a global Porifera microbiome survey, set out to establish the ecological and evolutionary drivers of these host–microbe interactions.We show that sponges are a reservoir of exceptional microbial diversity and major contributors to the total microbial diversity of the world’s oceans. Little commonality in species composition or structure is evident across the phylum, although symbiont communities are characterized by specialists and generalists rather than opportunists. Core sponge microbiomes are stable and characterized by generalist symbionts exhibiting amensal and/or commensal interactions. Symbionts that are phylogenetically unique to …


Intestinal Microbiota-Generated Metabolite Trimethylamine-N-Oxide And 5-Year Mortality Risk In Stable Coronary Artery Disease: The Contributory Role Of Intestinal Microbiota In A Courage-Like Patient Cohort, Vichai Senthong, Zeneng Wang, Xinmin S. Li, Yiying Fan, Yuping Wu, W. H. Wilson Tang, Stanley L. Hazen Jun 2016

Intestinal Microbiota-Generated Metabolite Trimethylamine-N-Oxide And 5-Year Mortality Risk In Stable Coronary Artery Disease: The Contributory Role Of Intestinal Microbiota In A Courage-Like Patient Cohort, Vichai Senthong, Zeneng Wang, Xinmin S. Li, Yiying Fan, Yuping Wu, W. H. Wilson Tang, Stanley L. Hazen

Mathematics and Statistics Faculty Publications

Background: Trimethylamine-N-oxide (TMAO), a metabolite derived from gut microbes and dietary phosphatidylcholine, is linked to both coronary artery disease pathogenesis and increased cardiovascular risks. The ability of plasma TMAO to predict 5-year mortality risk in patients with stable coronary artery disease has not been reported. This study examined the clinical prognostic value of TMAO in patients with stable coronary artery disease who met eligibility criteria for a patient cohort similar to that of the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial. Methods and Results: We examined the relationship between fasting plasma TMAO and all-cause mortality over 5-year …


Agenda: Coping With Water Scarcity In River Basins Worldwide: Lessons Learned From Shared Experiences, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment Jun 2016

Agenda: Coping With Water Scarcity In River Basins Worldwide: Lessons Learned From Shared Experiences, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment

Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)

Water scarcity is increasingly dominating headlines throughout the world. In the southwestern USA, the looming water shortages on the Colorado River system and the unprecedented drought in California are garnering the greatest attention. Similar stories of scarcity and crisis can be found across the globe, suggesting an opportunity for sharing lessons and innovations. For example, the Colorado River and Australia's Murray-Darling Basin likely can share many lessons, as both systems were over-allocated, feature multiple jurisdictions, face similar climatic risks and drought stresses, and struggle to balance human demands with environmental needs. In this conference we cast our net broadly, exploring …


Statistical Analysis And Modeling Health Data: A Longitudinal Study, Bhikhari Prasad Tharu Jun 2016

Statistical Analysis And Modeling Health Data: A Longitudinal Study, Bhikhari Prasad Tharu

USF Tampa Graduate Theses and Dissertations

Lung cancer has been considered one of the leading causes of deaths while cancer re- mains the second most common cause of deaths in the USA. Understanding the behavior of a disease over time could yield important information to make decisions about the disease. Statistical models could provide crucial clues and help to make a decision about the dis- ease, budget allocation, evaluation, and implement prevention. Longitudinal trend analysis of the diseases helps to understand long term effects and nature. Cholesterol level is one of the most contributing risk factors for Coronary Heart Disease. Studying cholesterol statistically helps to know …


Determining The Effectiveness Of Soil Treatment On Plant Stress Using Smart-Phone Cameras, Anurag Panwar Jun 2016

Determining The Effectiveness Of Soil Treatment On Plant Stress Using Smart-Phone Cameras, Anurag Panwar

USF Tampa Graduate Theses and Dissertations

Plants are vital to the health of our biosphere, and effectively sustaining their growth is fundamental to the existence of life on this planet. A critical aspect, which decides the sustainability of plant growth is the quality of soil. All other things being fixed, the quality of soil greatly impacts the plant stress, which in turn impacts overall health. Although plant stress manifests in many ways, one of the clearest indicators are colors of the leaves. In this thesis, we conducted an experimental study in a greenhouse for detecting plant stress caused by nutrient deficienceies in soil using smartphone cameras, …


Statistical Modeling Of Carbon Dioxide And Cluster Analysis Of Time Dependent Information: Lag Target Time Series Clustering, Multi-Factor Time Series Clustering, And Multi-Level Time Series Clustering, Doo Young Kim Jun 2016

Statistical Modeling Of Carbon Dioxide And Cluster Analysis Of Time Dependent Information: Lag Target Time Series Clustering, Multi-Factor Time Series Clustering, And Multi-Level Time Series Clustering, Doo Young Kim

USF Tampa Graduate Theses and Dissertations

The current study consists of three major parts. Statistical modeling, the connection between statistical modeling and cluster analysis, and proposing new methods to cluster time dependent information.

First, we perform a statistical modeling of the Carbon Dioxide (CO2) emission in South Korea in order to identify the attributable variables including interaction effects. One of the hot issues in the earth in 21st century is Global warming which is caused by the marriage between atmospheric temperature and CO2 in the atmosphere. When we confront this global problem, we first need to verify what causes the problem then we …


The University Of North Carolina At Greensboro Regional Undergraduate Mathematics Conference Abstracts, Jan Rychtář Jun 2016

The University Of North Carolina At Greensboro Regional Undergraduate Mathematics Conference Abstracts, Jan Rychtář

Furman University Electronic Journal of Undergraduate Mathematics

It was a very chaotic day, says Kathryn Sikes. Indeed, mutants spread everywhere, according to Brian Stadler. Bacterial wars raged all over the place, adds Dan MacMartin. Everybody was stealing, reported Christian Sykes. There were no limits to it, witnessed by Samuel Grundman. Only the fittest survived and got out of the prison, noted by Joseph Krenicky. The group was set free by Steven Piantadosi. We almost got lost in cyclic paths, said Heather Allmond. At least, our weight was a perfect number, smiles Michael Shiver, because we were not oversized thanks to Martha Shott. Finally, a picture was taken …


Effective Establishment Of Native Grasses On Roadsides In New England, Yulia Kuzovkina, John Campanelli, Cristian Schulthess, Robert Ricard, Glenn Dreyer Jun 2016

Effective Establishment Of Native Grasses On Roadsides In New England, Yulia Kuzovkina, John Campanelli, Cristian Schulthess, Robert Ricard, Glenn Dreyer

Other Publications and Reports

No abstract provided.


Oncogenic Pik3ca Mutations Reprogram Glutamine Metabolism In Colorectal Cancer, Yujun Hao, Yardena Samuels, Qingling Li, Dawid Krokowski, Bo-Jhih Guan, Chao Wang, Zhicheng Jin, Bohan Dong, Bo Cao, Xiujing Feng, Min Xiang, Claire Xu, Stephen Fink, Neal J. Meropol, Yan Xu Jun 2016

Oncogenic Pik3ca Mutations Reprogram Glutamine Metabolism In Colorectal Cancer, Yujun Hao, Yardena Samuels, Qingling Li, Dawid Krokowski, Bo-Jhih Guan, Chao Wang, Zhicheng Jin, Bohan Dong, Bo Cao, Xiujing Feng, Min Xiang, Claire Xu, Stephen Fink, Neal J. Meropol, Yan Xu

Chemistry Faculty Publications

Cancer cells often require glutamine for growth, thereby distinguishing them from most normal cells. Here we show that PIK3CA mutations reprogram glutamine metabolism by upregulating glutamate pyruvate transaminase 2 (GPT2) in colorectal cancer (CRC) cells, making them more dependent on glutamine. Compared with isogenic wild-type (WT) cells, PIK3CA mutant CRCs convert substantially more glutamine to alpha-ketoglutarate to replenish the tricarboxylic acid cycle and generate ATP. Mutant p110 alpha upregulates GPT2 gene expression through an AKT-independent, PDK1-RSK2-ATF4 signalling axis. Moreover, aminooxyacetate, which inhibits the enzymatic activity of aminotransferases including GPT2, suppresses xenograft tumour growth of CRCs with PIK3CA mutations, but not …


Identification Of A Disulfide Bridge In Sodium-Coupled Neutral Amino Acid Transporter 2(Snat2) By Chemical Modification, Chen Chen, Jiahong Wang, Ruiping Cai, Yanmen M. Yuan, Zhanyun Y. Guo, Christof Grewer, Zhou Zhang Jun 2016

Identification Of A Disulfide Bridge In Sodium-Coupled Neutral Amino Acid Transporter 2(Snat2) By Chemical Modification, Chen Chen, Jiahong Wang, Ruiping Cai, Yanmen M. Yuan, Zhanyun Y. Guo, Christof Grewer, Zhou Zhang

Chemistry Faculty Scholarship

Sodium-coupled neutral amino acid transporter 2 (SNAT2) belongs to solute carrier 38 (SLC38) family of transporters, which is ubiquitously expressed in mammalian tissues and mediates transport of small, neutral amino acids, exemplified by alanine(Ala, A). Yet structural data on SNAT2, including the relevance of intrinsic cysteine residues on structure and function, is scarce, in spite of its essential roles in many tissues. To better define the potential of intrinsic cysteines to form disulfide bonds in SNAT2, mutagenesis experiments and thiol-specific chemical modifications by N-ethylmaleimide (NEM) and methoxy-polyethylene glycol maleimide (mPEG-Mal, MW 5000) were performed, with or without the reducing regent …


Properties And Nutrient Status Of Degraded Soils In Luzon, Philippines, Michelle Ann M. Calubaquib, Ian A. Navarrete, Pearl B. Sanchez Jun 2016

Properties And Nutrient Status Of Degraded Soils In Luzon, Philippines, Michelle Ann M. Calubaquib, Ian A. Navarrete, Pearl B. Sanchez

Environmental Science Faculty Publications

A prerequisite to soil management, particularly in degraded soils, is a good knowledge of the characteristics and fertility status of degraded soil, which is fundamental to planning suitable soil management strategies for crop production purposes. The aim of this study was to determine the physico-chemical and mineralogical properties and fertility constraints of degraded soils in Luzon, Philippines. Ten surface soil samples were collected from 10 degraded soils representing the dominant soil series in Luzon Island. These soils were analyzed for physical, chemical and mineralogical properties. Results revealed that all soils have high clay content (except Bantay soil), which impedes cultivation. …


The Influence Of Juncus-Rhizosphere Dissolved Organic Matter On Coastal Plankton Communities, Brittany Zepernick, Robert Michael Mckay, George S. Bullerjahn, Jeffrey W. Krause, Behzad Mortazavi Jun 2016

The Influence Of Juncus-Rhizosphere Dissolved Organic Matter On Coastal Plankton Communities, Brittany Zepernick, Robert Michael Mckay, George S. Bullerjahn, Jeffrey W. Krause, Behzad Mortazavi

Honors Projects

Many aquatic plants produce copious amounts of dissolved organic matter (DOM) which enters surrounding waters and potentially stimulates planktonic activity. In the northern Gulf of Mexico, Juncus roemarianus (i.e. black needlerush) is a dominant marsh grass species residing in coastal zones and barrier islands. The below-ground biomass i.e. rhizosphere, can be consistently submerged, serving as a potential source of DOM to the surrounding waters. The lability and possible stimulatory effect of J. roemarianus DOM was examined for three plankton communities collected within the discharge region of Mobile Bay and adjacent waters of Gulf Shores, Alabama (less affected by Mobile Bay). …