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Full-Text Articles in Physical Sciences and Mathematics

Adaptable Xerogel-Layered Amperometric Biosensor Platforms On Wire Electrodes For Clinically Relevant Measurements, Lillian B. Hughes, Najwa Labban, Grace E. Conway, Julie A. Pollock, Michael C. Leopold Jun 2019

Adaptable Xerogel-Layered Amperometric Biosensor Platforms On Wire Electrodes For Clinically Relevant Measurements, Lillian B. Hughes, Najwa Labban, Grace E. Conway, Julie A. Pollock, Michael C. Leopold

Chemistry Faculty Publications

Biosensing strategies that employ readily adaptable materials for different analytes, can be miniaturized into needle electrode form, and function in bodily fluids represent a significant step toward the development of clinically relevant in vitro and in vivo sensors. In this work, a general scheme for 1st generation amperometric biosensors involving layer-by-layer electrode modification with enzyme-doped xerogels, electrochemically-deposited polymer, and polyurethane semi-permeable membranes is shown to achieve these goals. With minor modifications to these materials, sensors representing potential point-of-care medical tools are demonstrated to be sensitive and selective for a number of conditions. The potential for bedside measurements or continuous monitoring …


Evaluation Of Agricultural Land Cover Representations On Regional Climate Model Simulations In The Brazilian Cerrado, Stephanie A. Spera, Jonathan M. Winter, Jonathan W. Chipman May 2018

Evaluation Of Agricultural Land Cover Representations On Regional Climate Model Simulations In The Brazilian Cerrado, Stephanie A. Spera, Jonathan M. Winter, Jonathan W. Chipman

Geography and the Environment Faculty Publications

Examining interactions between large-scale land cover and land use change and regional climate in areas undergoing dynamic land transformations, like the Brazilian Cerrado, is crucial for understanding tradeoffs between human needs and ecosystem services. Yet regional climate models often do not include accurate land cover data of these complex landscapes. We use National Center for Atmospheric Research’s Weather Research and Forecasting (WRF) model coupled to the Noah-Multiparameterization (Noah-MP) land surface model to run 10-year climate simulations across Brazil to assess (1) whether an accurate, regionally validated land cover data set with two, new agricultural land cover classifications improves model simulation …


Agricultural Intensification Can Preserve The Brazilian Cerrado: Applying Lessons From Mato Grosso And Goia's To Brazil’S Last Agricultural Frontier, Stephanie A. Spera Aug 2017

Agricultural Intensification Can Preserve The Brazilian Cerrado: Applying Lessons From Mato Grosso And Goia's To Brazil’S Last Agricultural Frontier, Stephanie A. Spera

Geography and the Environment Faculty Publications

Food security and climate change are two pressing issues shaping the future of tropical land use. Brazil, home to abundant land that is rich in carbon, water, and biodiversity and often cleared for agropastoral and renewable energy purposes, is the ideal location for studying socioeconomic and environmental trade-offs of land use dynamics. Here, I use recent (2000–2016) land-use land-cover change dynamics in the established agricultural states of Mato Grosso and Goia's to demonstrate how incentivizing intensive agricultural practices and improving degraded pastures may be a means by which Brazil can increase agricultural production while conserving the remainder of the Cerrado. …


Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera Apr 2017

Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera

Geography and the Environment Faculty Publications

The Amazon basin has been subjected to unprecedented rates of land-use change over the past several decades, primarily as a result of the expansion of agriculture. Enhanced rain forest conservation efforts toward the end of the twentieth century slowed deforestation of the Amazon but, in turn, increased demand for land repurposing in the adjacent Cerrado (savanna) region, where conservation regulations are less strict. To maintain or increase yields while minimizing the need for additional land, agricultural producers adopted a form of intensification in which two rain-fed crops are planted within a single growing season (double cropping). Using 10 years (August …


The Relationship Between Tropical Cyclone Activity, Nutrient Loading, And Algal Blooms Over The Great Barrier Reef, Chelsea L. Parker, Amanda H. Lynch, Stephanie A. Spera, Keith R. Spangler Feb 2017

The Relationship Between Tropical Cyclone Activity, Nutrient Loading, And Algal Blooms Over The Great Barrier Reef, Chelsea L. Parker, Amanda H. Lynch, Stephanie A. Spera, Keith R. Spangler

Geography and the Environment Faculty Publications

The Great Barrier Reef, the world’s largest coral reef ecosystem, is subject to many environmental stressors. This study utilizes remotely sensed Moderate Resolution Imaging Spectroradiometer (MODIS) chlorophyll a concentration data to explore statistically significant relationships between local-scale tropical cyclone disturbance and relative water quality between 2004–2014. The study reveals that tropical cyclone activity reduces water quality at 8- and 16-day time lags. Relationships suggest that at early stages (during and just after cyclone activity) algal response is induced primarily through wind-driven sediment re-suspension. However, wind speed in isolation only increases minimum levels of chlorophyll a, rather than mean or …


Evaluating Infection Prevention Strategies In Out-Patient Dialysis Units Using Agent-Based Modeling, Joanna R. Wares, Barry Lawson, Douglas Shemin, Erika D'Agata May 2016

Evaluating Infection Prevention Strategies In Out-Patient Dialysis Units Using Agent-Based Modeling, Joanna R. Wares, Barry Lawson, Douglas Shemin, Erika D'Agata

Department of Math & Statistics Faculty Publications

Patients receiving chronic hemodialysis (CHD) are among the most vulnerable to infections caused by multidrug-resistant organisms (MDRO), which are associated with high rates of morbidity and mortality. Current guidelines to reduce transmission of MDRO in the out-patient dialysis unit are targeted at patients considered to be high-risk for transmitting these organisms: those with infected skin wounds not contained by a dressing, or those with fecal incontinence or uncontrolled diarrhea. Here, we hypothesize that targeting patients receiving antimicrobial treatment would more effectively reduce transmission and acquisition of MDRO. We also hypothesize that environmental contamination plays a role in the dissemination of …


Effects Of A Pyrrole-Based, Microtubule-Depolymerizing Compound On Raw 264.7 Macrophages, John A. Ciemnieckia, Clarke P. Lewis, John T. Gupton, Krista J. Stenger Feb 2016

Effects Of A Pyrrole-Based, Microtubule-Depolymerizing Compound On Raw 264.7 Macrophages, John A. Ciemnieckia, Clarke P. Lewis, John T. Gupton, Krista J. Stenger

Biology Faculty Publications

RAW 264.7 murine macrophages were exposed to the pyrrole-based compound 3,5-Dibromo-4-(3,4-dimethoxyphenyl)-1H-pyrrole-2-carboxylic acid ethyl ester (JG-03-14), which is a known microtubule depolymerizing agent with antitumor activity [1,2,3]. In this study exposure to JG-03-14 reduced the production of pro-inflammatory molecules by macrophages activated with lipopolysaccharide (LPS). Treatment with the pyrrole-based compound decreased the concentration of tumor necrosis factor-α (TNF-α) and nitric oxide (NO) released from the macrophages. Exposure to JG-03-14 also decreased TNF-α mRNA expression levels and the protein expression levels of inducible nitric oxide synthase (iNOS), the enzyme responsible for NO production in the activated macrophages. Furthermore, JG-03-14 treatment significantly changed …


Forest Birds Respond To The Spatial Pattern Of Exurban Development In The Mid-Atlantic Region, Usa, Todd R. Lookingbill, Marcela Suarez-Rubio Jan 2016

Forest Birds Respond To The Spatial Pattern Of Exurban Development In The Mid-Atlantic Region, Usa, Todd R. Lookingbill, Marcela Suarez-Rubio

Geography and the Environment Faculty Publications

Housing development beyond the urban fringe (i.e., exurban development) is one of the fastest growing forms of land-use change in the United States. Exurban development's attraction to natural and recreational amenities has raised concerns for conservation and represents a potential threat to wildlife. Although forest-dependent species have been found particularly sensitive to low housing densities, it is unclear how the spatial distribution of houses affects forest birds. The aim of this study was to assess forest bird responses to changes in the spatial pattern of exurban development and also to examine species responses when forest loss and forest fragmentation were …


Soybean Development: The Impact Of A Decade Of Agricultural Change On Urban And Economic Growth In Mato Grosso, Brazil, Peter Richards, Heitor Pellegrina, Leah Vanwey, Stephanie A. Spera Apr 2015

Soybean Development: The Impact Of A Decade Of Agricultural Change On Urban And Economic Growth In Mato Grosso, Brazil, Peter Richards, Heitor Pellegrina, Leah Vanwey, Stephanie A. Spera

Geography and the Environment Faculty Publications

In this research we consider the impact of export-driven, soybean agriculture in Mato Grosso on regional economic growth. Here we argue that the soybean sector has served as a motor to the state’s economy by increasing the demand for services, housing, and goods, and by providing a source of investment capital to the non-agricultural sector. Specifically, we show that each square kilometer of soybean production supports 2.5 formal sector jobs outside of agriculture, and the equivalent of approximately 150,000 US in annual, non-agricultural GDP. We also show that annual gains in non-agricultural employment and GDP are closely tied to soybean …


Recent Cropping Frequency, Expansion, And Abandonment In Mato Grosso, Brazil Had Selective Land Characteristics, Stephanie A. Spera, Avery S. Cohn, Leah K. Vanwey, Jack F. Mustard, Bernardo F.T. Rudorff, Marcos Adami Jun 2014

Recent Cropping Frequency, Expansion, And Abandonment In Mato Grosso, Brazil Had Selective Land Characteristics, Stephanie A. Spera, Avery S. Cohn, Leah K. Vanwey, Jack F. Mustard, Bernardo F.T. Rudorff, Marcos Adami

Geography and the Environment Faculty Publications

This letter uses satellite remote sensing to examine patterns of cropland expansion, cropland abandonment, and changing cropping frequency in Mato Grosso, Brazil from 2001 to 2011. During this period, Mato Grosso emerged as a globally important center of agricultural production. In 2001, 3.3 million hectares of mechanized agriculture were cultivated in Mato Grosso, of which 500 000 hectares had two commercial crops per growing season (double cropping). By 2011, Mato Grosso had 5.8 million hectares of mechanized agriculture, of which 2.9 million hectares were double cropped. We found these agricultural changes to be selective with respect to land attributes —significant …


A Loose Domain Swapping Organization Confers A Remarkable Stability To The Dimeric Structure Of The Arginine Binding Protein From Thermotoga Maritima, Alessia Ruggiero, Jonathan D. Dattelbaum, Maria Staiano, Rita Berisio, Sabato D'Auria, Luigi Vitagliano Jan 2014

A Loose Domain Swapping Organization Confers A Remarkable Stability To The Dimeric Structure Of The Arginine Binding Protein From Thermotoga Maritima, Alessia Ruggiero, Jonathan D. Dattelbaum, Maria Staiano, Rita Berisio, Sabato D'Auria, Luigi Vitagliano

Chemistry Faculty Publications

The arginine binding protein from Thermatoga maritima (TmArgBP), a substrate binding protein (SBP) involved in the ABC system of solute transport, presents a number of remarkable properties. These include an extraordinary stability to temperature and chemical denaturants and the tendency to form multimeric structures, an uncommon feature among SBPs involved in solute transport. Here we report a biophysical and structural characterization of the TmArgBP dimer. Our data indicate that the dimer of the protein is endowed with a remarkable stability since its full dissociation requires high temperature as well as SDS and urea at high concentrations. In order to elucidate …


Periplasmic Binding Proteins In Thermophiles: Characterization And Potential Application Of An Arginine-Binding Protein From Thermotoga Maritima: A Brief Thermo-Story, Alessio Ausili, Maria Staiano, Jonathan D. Dattelbaum, Antonio Varriale, Alessandro Capo, Sabato D'Auria Jan 2013

Periplasmic Binding Proteins In Thermophiles: Characterization And Potential Application Of An Arginine-Binding Protein From Thermotoga Maritima: A Brief Thermo-Story, Alessio Ausili, Maria Staiano, Jonathan D. Dattelbaum, Antonio Varriale, Alessandro Capo, Sabato D'Auria

Chemistry Faculty Publications

Arginine-binding protein from the extremophile Thermotoga maritima is a 27.7 kDa protein possessing the typical two-domain structure of the periplasmic binding proteins family. The protein is characterized by a very high specificity and affinity to bind to arginine, also at high temperatures. Due to its features, this protein could be taken into account as a potential candidate for the design of a biosensor for arginine. It is important to investigate the stability of proteins when they are used for biotechnological applications. In this article, we review the structural and functional features of an arginine-binding protein from the extremophile Thermotoga maritima …


Structurally Diverse Hamigerans From The New Zealand Marine Sponge Hamigera Tarangaensis: Nmr-Directed Isolation, Structure Elucidation And Antifungal Activity, A. Jonathan Singh, Jonathan D. Dattelbaum, Jessica J. Field, Zlatka Smart, Ethan F. Woolly, Jacqueline M. Barber, Rosemary Heathcott, John H. Miller, Peter T. Northcote Jan 2013

Structurally Diverse Hamigerans From The New Zealand Marine Sponge Hamigera Tarangaensis: Nmr-Directed Isolation, Structure Elucidation And Antifungal Activity, A. Jonathan Singh, Jonathan D. Dattelbaum, Jessica J. Field, Zlatka Smart, Ethan F. Woolly, Jacqueline M. Barber, Rosemary Heathcott, John H. Miller, Peter T. Northcote

Chemistry Faculty Publications

The NMR-directed investigation of the New Zealand marine sponge Hamigera tarangaensis has afforded ten new compounds of the hamigeran family, and a new 13-epi-verrucosane congener. Notably, hamigeran F (6) possesses an unusual carbon–carbon bond between C-12 and C-13, creating an unprecedented skeleton within this class. In particular, the structural features of 6, hamigeran H (10) and hamigeran J (12) imply a diterpenoid origin, which has allowed the putative biogenesis of three hamigeran carbon skeletons to be proposed based on geranyl geranyl pyrophosphate. All new hamigerans exhibited micromolar activity towards the HL-60 …


Challenging Disciplinary Boundaries In The First Year: A New Introductory Integrated Science Course For Stem Majors, Lisa Gentile, Lester Caudill, Mirela Fetea, April L. Hill, Kathy Hoke, Barry Lawson, Ovidiu Z. Lipan, Michael Kerckhove, Carol A. Parish, Krista J. Stenger, Doug Szajda May 2012

Challenging Disciplinary Boundaries In The First Year: A New Introductory Integrated Science Course For Stem Majors, Lisa Gentile, Lester Caudill, Mirela Fetea, April L. Hill, Kathy Hoke, Barry Lawson, Ovidiu Z. Lipan, Michael Kerckhove, Carol A. Parish, Krista J. Stenger, Doug Szajda

Department of Math & Statistics Faculty Publications

To help undergraduates make connections among disciplines so they are able to approach, evaluate, and contribute to the solutions of important global problems, our campus has been focused on interdisciplinary research and education opportunities across the science, technology, engineering, and mathematics (STEM) disciplines. This paper describes the mobilization, planning, and implementation of a first-year interdisciplinary course for STEM majors that integrates key concepts found in traditional first-semester biology, chemistry, computer science, mathematics, and physics courses. This team-taught course, Integrated Quantitative Science (IQS), is half of a first-year student’s schedule in both semesters and is composed of a double lecture and …


Challenging Disciplinary Boundaries In The First Year: A New Introductory Integrated Science Course For Stem Majors, Lisa Gentile, Lester Caudill, Mirela Fetea, April L. Hill, Kathy Hoke, Barry Lawson, Ovidiu Z. Lipan, Michael Kerckhove, Carol A. Parish, Krista J. Stenger, Doug Szajda May 2012

Challenging Disciplinary Boundaries In The First Year: A New Introductory Integrated Science Course For Stem Majors, Lisa Gentile, Lester Caudill, Mirela Fetea, April L. Hill, Kathy Hoke, Barry Lawson, Ovidiu Z. Lipan, Michael Kerckhove, Carol A. Parish, Krista J. Stenger, Doug Szajda

Biology Faculty Publications

To help undergraduates make connections among disciplines so they are able to approach, evaluate, and contribute to the solutions of important global problems, our campus has been focused on interdisciplinary research and education opportunities across the science, technology, engineering, and mathematics (STEM) disciplines. This paper describes the mobilization, planning, and implementation of a first-year interdisciplinary course for STEM majors that integrates key concepts found in traditional first-semester biology, chemistry, computer science, mathematics, and physics courses. This team-taught course, Integrated Quantitative Science (IQS), is half of a first-year student’s schedule in both semesters and is composed of a double lecture and …


Grts And Graphs: Monitoring Natural Resources In Urban Landscapes, Todd R. Lookingbill, John Paul Schmit, Shawn L. Carter Jan 2012

Grts And Graphs: Monitoring Natural Resources In Urban Landscapes, Todd R. Lookingbill, John Paul Schmit, Shawn L. Carter

Geography and the Environment Faculty Publications

Environmental monitoring programs are an important tool for providing land managers with a scientific basis for management decisions. However, many ecological processes operate on spatial scales that transcend management boundaries (Schonewald-Cox 1988). For example, adjacent lands may influence protected-area resources via edge effects, source-sink dynamics, or invasion processes (Jones et al. 2009). Hydrologic alterations outside management units also may have profound effects on the integrity of resources being managed (Pringle 2000). The impacts of climate change are presenting challenges to resource management at local-to-global scales (Karl et al. 2009). This potential disparity between ecological and political boundaries presents an interesting …


Crystallization And Preliminary X-Ray Crystallographic Analysis Of Ligand-Free And Arginine-Bound Forms Of Thermotoga Maritima Arginine-Binding Protein, Alessia Ruggiero, Jonathan D. Dattelbaum, Anna Pennacchio, Luisa Iozzion, Maria Staiano, Matthew S. Luchansky, Bryan S. Der, Rita Berisio, Sabato D'Auria, Luigi Vitagliano Jan 2011

Crystallization And Preliminary X-Ray Crystallographic Analysis Of Ligand-Free And Arginine-Bound Forms Of Thermotoga Maritima Arginine-Binding Protein, Alessia Ruggiero, Jonathan D. Dattelbaum, Anna Pennacchio, Luisa Iozzion, Maria Staiano, Matthew S. Luchansky, Bryan S. Der, Rita Berisio, Sabato D'Auria, Luigi Vitagliano

Chemistry Faculty Publications

The arginine-binding protein from Thermotoga maritima (TmArgBP) is an arginine-binding component of the ATP-binding cassette (ABC) transport system in this hyperthermophilic bacterium. This protein is endowed with an extraordinary stability towards thermal and chemical denaturation. Its structural characterization may provide useful insights for the clarification of structure– stability relationships and for the design of new biosensors. Crystallization trials were set up for both arginine-bound and ligand-free forms of TmArgBP and crystals suitable for crystallographic investigations were obtained for both forms. Ordered crystals of the arginine adduct of TmArgBP could only be obtained by using the detergent LDAO as an additive …


Impact Of Interdisciplinary Undergraduate Research In Mathematics And Biology On The Development Of A New Course Integrating Five Stem Disciplines, Lester Caudill, April L. Hill, Kathy Hoke, Ovidiu Z. Lipan Oct 2010

Impact Of Interdisciplinary Undergraduate Research In Mathematics And Biology On The Development Of A New Course Integrating Five Stem Disciplines, Lester Caudill, April L. Hill, Kathy Hoke, Ovidiu Z. Lipan

Department of Math & Statistics Faculty Publications

Funded by innovative programs at the National Science Foundation and the Howard Hughes Medical Institute, University of Richmond faculty in biology, chemistry, mathematics, physics, and computer science teamed up to offer first- and second-year students the opportunity to contribute to vibrant, interdisciplinary research projects. The result was not only good science but also good science that motivated and informed course development. Here, we describe four recent undergraduate research projects involving students and faculty in biology, physics, mathematics, and computer science and how each contributed in significant ways to the conception and implementation of our new Integrated Quantitative Science course, a …


Impact Of Interdisciplinary Undergraduate Research In Mathematics And Biology On The Development Of A New Course Integrating Five Stem Disciplines, Lester Caudill, April L. Hill, Kathy Hoke, Ovidiu Z. Lipan Oct 2010

Impact Of Interdisciplinary Undergraduate Research In Mathematics And Biology On The Development Of A New Course Integrating Five Stem Disciplines, Lester Caudill, April L. Hill, Kathy Hoke, Ovidiu Z. Lipan

Biology Faculty Publications

Funded by innovative programs at the National Science Foundation and the Howard Hughes Medical Institute, University of Richmond faculty in biology, chemistry, mathematics, physics, and computer science teamed up to offer first- and second-year students the opportunity to contribute to vibrant, interdisciplinary research projects. The result was not only good science but also good science that motivated and informed course development. Here, we describe four recent undergraduate research projects involving students and faculty in biology, physics, mathematics, and computer science and how each contributed in significant ways to the conception and implementation of our new Integrated Quantitative Science course, a …


Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum Jan 2010

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum

Chemistry Faculty Publications

Members of the periplasmic binding protein superfamily are involved in the selective passage of ligands through bacterial cell membranes. The hyperthermophilic eubacterium Thermotoga maritima was found to encode a highly stable and specific periplasmic arginine-binding protein (TM0593). Following signal sequence removal and overexpression in Escherichia coli, TM0593 was purified by thermoprecipitation and affinity chromatography. The ultra-stable protein with a monomeric molecular weight of 27.7 kDa was found to exist as both a homodimer and homotrimer at appreciable concentrations even under strongly denaturing conditions, with an estimated transition temperature of 116 °C. Its multimeric structure may provide further evidence of …


Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima. 2. Molecular Organization And Structural Stability, Andrea Scirè, Anna Marabotti, Maria Staiano, Luisa Iozzion, Matthew S. Luchansky, Bryan S. Der, Jonathan D. Dattelbaum, Fabio Tanfani, Sabato D'Auria Jan 2010

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima. 2. Molecular Organization And Structural Stability, Andrea Scirè, Anna Marabotti, Maria Staiano, Luisa Iozzion, Matthew S. Luchansky, Bryan S. Der, Jonathan D. Dattelbaum, Fabio Tanfani, Sabato D'Auria

Chemistry Faculty Publications

ABC transport systems provide selective passage of metabolites across cell membranes and typically require the presence of a soluble binding protein with high specificity to a specific ligand. In addition to their primary role in nutrient gathering, the binding proteins associated with bacterial transport systems have been studied for their potential to serve as design scaffolds for the development of fluorescent protein biosensors. In this work, we used Fourier transform infrared spectroscopy and molecular dynamics simulations to investigate the physicochemical properties of a hyperthermophilic binding protein from Thermotoga maritima. We demonstrated preferential binding for the polar amino acid arginine …


Biology In Mathematics At The University Of Richmond, Lester Caudill Jan 2009

Biology In Mathematics At The University Of Richmond, Lester Caudill

Department of Math & Statistics Faculty Publications

In an effort to meet the needs of science students for modeling skills, three new courses have been created at the University of Richmond: Scientific Calculus I and II, and Mathematical Models in Biology and Medicine. The courses are described, and lessons learned and future directions are discussed.


An Eye-Opening Approach To Developing And Communicating Integrated Environmental Assessments, Todd R. Lookingbill, William C. Dennison, Tim J.B. Carruthers, Jane M. Hawkey, Shawn L. Carter Jan 2007

An Eye-Opening Approach To Developing And Communicating Integrated Environmental Assessments, Todd R. Lookingbill, William C. Dennison, Tim J.B. Carruthers, Jane M. Hawkey, Shawn L. Carter

Geography and the Environment Faculty Publications

Communication among managers, the public, and scientists is the key to successful ecosystem management; however, the varied perspectives and interests of these groups can make such communication difficult. One way to achieve effective communication is to develop a common knowledge base by combining syntheses of key scientific results with information-rich visual elements. Within a management landscape, integrated environmental assessments provide a useful framework for evaluating resources and directing management efforts. The integrated assessment process involves (1) initial investigation, (2) development of a conceptual framework, (3) data navigation, (4) environmental report cards, and (5) science communication. Each step requires the synthesis …


Urer, The Transcriptional Activator Of The Proteus Mirabilis Urease Gene Cluster, Is Required For Urease Activity And Virulence In Experimental Urinary Tract Infections, Jonathan D. Dattelbaum, C. Virginia Lockatell, David E. Johnson, Harry L.T. Mobley Jan 2003

Urer, The Transcriptional Activator Of The Proteus Mirabilis Urease Gene Cluster, Is Required For Urease Activity And Virulence In Experimental Urinary Tract Infections, Jonathan D. Dattelbaum, C. Virginia Lockatell, David E. Johnson, Harry L.T. Mobley

Chemistry Faculty Publications

Proteus mirabilis, a cause of complicated urinary tract infection, produces urease, an essential virulence factor for this species. UreR, a member of the AraC/XylS family of transcriptional regulators, positively activates expression of the ure gene cluster in the presence of urea. To specifically evaluate the contribution of UreR to urease activity and virulence in the urinary tract, a ureR mutation was introduced into P. mirabilis HI4320 by homologous recombination. The isogenic ureR::aphA mutant, deficient in UreR production, lacked measurable urease activity. Expression was not detected in the UreR-deficient strain by Western blotting with monoclonal antibodies raised against UreD. Urease …


A Comparison Of The Low Mode And Monte Carlo Conformational Search Methods, Carol A. Parish, Rosina Lombardi, Kent Sinclair, Emelyn Smith, Alla Goldberg, Melissa Rappleye, Myrianne Dure Oct 2002

A Comparison Of The Low Mode And Monte Carlo Conformational Search Methods, Carol A. Parish, Rosina Lombardi, Kent Sinclair, Emelyn Smith, Alla Goldberg, Melissa Rappleye, Myrianne Dure

Chemistry Faculty Publications

The Low Mode (LM) and Monte Carlo (MC) conformational search methods were compared on three diverse molecular systems; (4R, 5S, 6S, 7R)-hexahydro-5,6-dihydroxy-1,3,4,7-tetrakis(phenylmethyl)-2H-1,3-diazapin-2-one (1), 2-methoxy-2-phenyl-2-triflouromethyl-N-α-methyl benzyl propanamide (2) and a trimeric 39-membered polyazamacrolide (3). We find that either method, or a combination of the methods, is equally efficient at searching the conformational space of the smaller molecular systems while a 50:50 hybrid of Low Mode and Monte Carlo is most efficient at searching the space of the larger molecular system.


Identification Of The Domains Of Urer, An Arac-Like Transcriptional Regulator Of The Urease Gene Cluster In Proteus Mirabilis, Carrie A. Poore, Christopher Coker, Jonathan D. Dattelbaum, Harry L.T. Mobley Jan 2001

Identification Of The Domains Of Urer, An Arac-Like Transcriptional Regulator Of The Urease Gene Cluster In Proteus Mirabilis, Carrie A. Poore, Christopher Coker, Jonathan D. Dattelbaum, Harry L.T. Mobley

Chemistry Faculty Publications

Proteus mirabilis urease catalyzes the hydrolysis of urea to CO2 and NH3, resulting in urinary stone formation in individuals with complicated urinary tract infections. UreR, a member of the AraC family, activates transcription of the genes encoding urease enzyme subunits and accessory proteins, ureDABCEFG, as well as its own transcription in the presence of urea. Based on sequence homology with AraC, we hypothesized that UreR contains both a dimerization domain and a DNA-binding domain. A translational fusion of the leucine zipper dimerization domain (amino acids 302 to 350) of C/EBP and the C-terminal half of UreR …


Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Histological Sections, Gary P. Radice, Mary Kate Boggiano, Mark Desantis, Peter M. Larson, Joseph Oppong, Matthew T. Smetanick, Todd M. Stevens, James Tripp, Rebecca A. Weber, Michael Kerckhove, Rafael O. De Sá Oct 1999

Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Histological Sections, Gary P. Radice, Mary Kate Boggiano, Mark Desantis, Peter M. Larson, Joseph Oppong, Matthew T. Smetanick, Todd M. Stevens, James Tripp, Rebecca A. Weber, Michael Kerckhove, Rafael O. De Sá

Biology Faculty Publications

Reconstructing three dimensional structures (3DR) from histological sections has always been difficult but is becoming more accessible with the assistance of digital imaging. We sought to assemble a low cost system using readily available hardware and software to generate 3DR for a study of tadpole chondrocrania. We found that a combination of RGB camera, stereomicroscope, and Apple Macintosh PowerPC computers running NIH Image, Object Image, Rotater. and SURFdriver software provided acceptable reconstructions. These are limited in quality primarily by the distortions arising from histological protocols rather than hardware or software.


Two-Photon Excitation Of Rhenium Metal-Ligand Complexes, Joseph R. Lakowicz, Felix N. Castellano, Ignacy Gryczynski, Zygmunt Gryczynski, Jonathan D. Dattelbaum Jan 1999

Two-Photon Excitation Of Rhenium Metal-Ligand Complexes, Joseph R. Lakowicz, Felix N. Castellano, Ignacy Gryczynski, Zygmunt Gryczynski, Jonathan D. Dattelbaum

Chemistry Faculty Publications

We describe the emission spectral properties of two rhenium metal-ligand complexes with one and two-photon excitation, Re(bpy)2(CO)3Cl and [Re(bpy)(CO)3CH3CN]+, where bpy is 2,2’-bipyridyl and CH3CN is acetonitrile. Similar emission spectra and intensity decay times characteristic of the metal-to-ligand charge transfer state were observed for one- and two-photon excitation. The lifetime and quantum yield of the acetonitrile complex are approximately 14-fold higher than that of the chloride complex. Both complexes display high anisotropies near 0.33 in frozen solution with one-photon excitation. Two-photon excitation results in anisotropies about 40% larger, …