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Stalk Borer Migration Is Beginning, Erin W. Hodgson 2010 Iowa State University

Stalk Borer Migration Is Beginning, Erin W. Hodgson

Integrated Crop Management News

Warm June temperatures have accelerated insect growth and development, including stalk borers. Start looking for migrating stalk borer larvae when 10 percent movement is predicted. The 2010 forecast for 10 percent stalk borer movement in Iowa is starting this week (Fig. 1).


A High-Throughput Transient Gene Expression System For Switchgrass (Panicum Virgatum L.) Seedlings, Xinlu Chen, Raymie Equi, Holly Baxter, Kyle Berk, Jin Han, Sujata Agarwal, Janice Zale 2010 University of Tennessee - Knoxville

A High-Throughput Transient Gene Expression System For Switchgrass (Panicum Virgatum L.) Seedlings, Xinlu Chen, Raymie Equi, Holly Baxter, Kyle Berk, Jin Han, Sujata Agarwal, Janice Zale

Plant Sciences Publications and Other Works

Abstract

Background

Grasses are relatively recalcitrant to genetic transformation in comparison to certain dicotyledons, yet they constitute some of the most important biofuel crops. Genetic transformation of switchgrass (Panicum virgatum L.) has previously been reported after cocultivation of explants with Agrobacterium and biolistics of embryogenic calli. Experiments to increase transient gene expression in planta may lead to stable transformation methods with increased efficiency.

Results

A high-throughput Agrobacterium-mediated transient gene expression system has been developed for in planta inoculation of germinating switchgrass seedlings. Four different Agrobacterium strains were compared for their ability to infect switchgrass seedlings, and strain AGL1 was ...


Glandularia Canadensis (L.) Nutt., William E. McClain 2010 Eastern Illinois University

Glandularia Canadensis (L.) Nutt., William E. Mcclain

Specimens by Name

No abstract provided.


Oas1 Polymorphisms Are Associated With Susceptibility To West Nile Encephalitis In Horses, Jonathan J. Rios, Joann G. W. Fleming, Uneeda K. Bryant, Craig N. Carter, John C. Huber Jr., Maureen T. Long, Thomas E. Spencer, David L. Adelson 2010 University of Texas Southwestern Medical Center at Dallas

Oas1 Polymorphisms Are Associated With Susceptibility To West Nile Encephalitis In Horses, Jonathan J. Rios, Joann G. W. Fleming, Uneeda K. Bryant, Craig N. Carter, John C. Huber Jr., Maureen T. Long, Thomas E. Spencer, David L. Adelson

Veterinary Diagnostic Laboratory Faculty Publications

West Nile virus, first identified within the United States in 1999, has since spread across the continental states and infected birds, humans and domestic animals, resulting in numerous deaths. Previous studies in mice identified the Oas1b gene, a member of the OAS/RNASEL innate immune system, as a determining factor for resistance to West Nile virus (WNV) infection. A recent case-control association study described mutations of human OAS1 associated with clinical susceptibility to WNV infection. Similar studies in horses, a particularly susceptible species, have been lacking, in part, because of the difficulty in collecting populations sufficiently homogenous in their infection ...


A Computational Biology Approach To The Analysis Of Complex Physiology: Coagulation, Fibrinolysis, And Wound Healing, Nathan Menke 2010 Virginia Commonwealth University

A Computational Biology Approach To The Analysis Of Complex Physiology: Coagulation, Fibrinolysis, And Wound Healing, Nathan Menke

Theses and Dissertations

The birth of complexity research derives from the logical progression of advancement in the scientific field afforded by reductionist theory. We present in silico models of two complex physiological processes, wound healing and coagulation/fibrinolysis based on two common tools in the study of complex physiology: ordinary differential equations (ODE) and Agent Based Modeling (ABM). The strengths of these two approaches are well-suited in the analysis of clinical paradigms such as wound healing and coagulation. The complex interactions that characterize acute wound healing have stymied the development of effective therapeutic modalities. The use of computational models holds the promise to ...


A Novel Role Of Sirt1 In Sildenafil Induced Cardioprotection In Mice, Mona Shalwala 2010 Virginia Commonwealth University

A Novel Role Of Sirt1 In Sildenafil Induced Cardioprotection In Mice, Mona Shalwala

Theses and Dissertations

Phosphodiesterase-5 inhibitor, sildenafil (SIL) protects against myocardial ischemia/reperfusion (I-R) injury. We hypothesized that SIL-induced protection may be mediated through activation of SIRT1, an enzyme which deacetylates proteins involved in cellular stress response. Adult male ICR mice were treated with SIL (0.7mg/kg ip), Resveratrol (RSV) (5mg/kg ip) (positive control), or saline (0.2 ml ip). The hearts were harvested 24 h later and homogenized for SIRT1 activity analysis. Both SIL and RSV increased cardiac SIRT1 activity (P<0.001) as compared to Saline. Adult mouse ventricular cardiomyocytes pre-treated with either SIL or RSV (1µM) in vitro also upregulated SIRT1 activity (P<0.05). SIL also reduced infarct size following 30 min. ischemia and 24 h reperfusion in vivo. Sirtinol (5mg/kg in 10% DMSO, ip), a SIRT1 inhibitor abolished the infarct-limiting effect of SIL and RSV (P<0.001). In conclusion, activation of SIRT1 by SIL plays an essential role in cardioprotection against I-R injury.


Age And Sex Differences In Duration Of Pre-Hospital Delay, Hospital Treatment Practices, And Short-Term Outcomes In Patients Hospitalized With An Acute Coronary Syndrome/Acute Myocardial Infarction: A Dissertation, Hoa L. Nguyen 2010 University of Massachusetts Medical School

Age And Sex Differences In Duration Of Pre-Hospital Delay, Hospital Treatment Practices, And Short-Term Outcomes In Patients Hospitalized With An Acute Coronary Syndrome/Acute Myocardial Infarction: A Dissertation, Hoa L. Nguyen

GSBS Dissertations and Theses

Background
The prompt seeking of medical care after the onset of symptoms suggestive of acute coronary syndromes (ACS)/acute myocardial infarction (AMI) is associated with the receipt of coronary reperfusion therapy, and effective cardiac medications in patients with an ACS/AMI and is crucial to reducing mortality and the risk of serious clinical complications in these patients. Despite declines in important hospital complications and short-term death rates in patients hospitalized with an ACS/AMI, several patient groups remain at increased risk for these adverse outcomes, including women and the elderly. However, recent trends in age and sex differences in extent ...


Glycosylation, Assembly And Trafficking Of Cardiac Potassium Channel Complexes: A Dissertation, Kshama D. Chandrasekhar 2010 University of Massachusetts Medical School

Glycosylation, Assembly And Trafficking Of Cardiac Potassium Channel Complexes: A Dissertation, Kshama D. Chandrasekhar

GSBS Dissertations and Theses

KCNE peptides are a class of type I transmembrane ß-subunits that assemble with and modulate the gating and ion conducting properties of a variety of voltage-gated K+ channels. Accordingly, mutations that affect the assembly and trafficking of K+ channel/KCNE complexes give rise to disease. The cellular mechanisms that oversee KCNE peptide assembly with voltage-gated K+ channels have yet to be elucidated. In Chapter II, we show that KCNE1 peptides are retained in the early stages of the secretory pathway until they co-assemble with KCNQ1 K+ channel subunits. Co-assembly with KCNQ1 channel subunits mediates efficient forward trafficking of KCNE1 peptides ...


Natural Competence In Thermoanaerobacter And Thermoanaerobacterium Species, A Joe Shaw, David A. Hogsett, Lee R. Lynd 2010 Dartmouth College

Natural Competence In Thermoanaerobacter And Thermoanaerobacterium Species, A Joe Shaw, David A. Hogsett, Lee R. Lynd

Open Dartmouth: Faculty Open Access Articles

Low-G+C thermophilic obligate anaerobes in the class Clostridia are considered among the bacteria most resistant to genetic engineering due to the difficulty of introducing foreign DNA, thus limiting the ability to study and exploit their native hydrolytic and fermentative capabilities. Here, we report evidence of natural genetic competence in 13 Thermoanaerobacter and Thermoanaerobacterium strains previously believed to be difficult to transform or genetically recalcitrant.

In Thermoanaerobacterium saccharolyticum JW/SL-YS485, natural competence- mediated DNA incorporation occurs during the exponential growth phase with both replicating plasmid and homologous recombination-based integration, and circular or linear DNA. In T. saccharolyticum, disruptions of genes ...


Temperature Fluctuations Have And May Continue To Inhibit Corn Emergence, Roger Elmore, Lori Abendroth 2010 Iowa State University

Temperature Fluctuations Have And May Continue To Inhibit Corn Emergence, Roger Elmore, Lori Abendroth

Integrated Crop Management News

Corn planting proceeded at an all-time record this spring. We’ve experienced one of the best planting seasons ever in Iowa. According to the most recentUSDA-NASS report (2 May 2010), 84 percent of Iowa’s corn was planted with cropping districts ranging from 69 percent complete in south central Iowa to 92 percent complete in north central Iowa. Overall, corn has been planted within the recommended window which should serve to maximize yield potential relative to planting date.


Iowa State Receives $200,000 Grant To Develop Biomass Crops In Southern Iowa, Emily A. Heaton 2010 Iowa State University

Iowa State Receives $200,000 Grant To Develop Biomass Crops In Southern Iowa, Emily A. Heaton

Integrated Crop Management News

Iowa State University has been awarded a $200,000 grant to develop perennial cash crops for southern Iowa. The grant was awarded by the U.S. Department of Energy's Sun Grant Initiative to fund biomass crop production research and forms a partnership with the U.S. Department of Agriculture Natural Resources Conservation Service and Agricultural Research Service.


What We Talk About When We Talk About The Soul, Stephen Asma 2010 Columbia College Chicago

What We Talk About When We Talk About The Soul, Stephen Asma

Stephen T Asma

The author discusses the popularity among college students of the concept of the soul, and attempts to place it in its proper context. He dispenses with orthodox theological arguments and New Age arguments as scientifically untenable. He takes a so-called Wittgensteinian approach, noting soul's linguistic significance. He analyzes expressions which use the concept of soul and concludes that they are qualitatively different from testable factual expressions. He notes that soul talk is about hopes and aspirations, inspiration, or feelings deeper than friendship. He assigns it meaning outside of scientific concepts. He likens expressions of soul to creative and ethical ...


Daily To Decadal Patterns Of Precipitation, Humidity, And Photosynthetic Physiology Recorded In The Spines Of The Columnar Cactus, Carnegiea Gigantea, N. B. English, D. L. Dettman, D. R. Sandquist, David G. Williams 2010 University of Wyoming

Daily To Decadal Patterns Of Precipitation, Humidity, And Photosynthetic Physiology Recorded In The Spines Of The Columnar Cactus, Carnegiea Gigantea, N. B. English, D. L. Dettman, D. R. Sandquist, David G. Williams

Botany Faculty Publications

Isotopic analyses of cactus spines grown serially from the apex of long-lived columnar cactuses may be useful for climatological and ecological studies if time series can be reliably determined from spines. To characterize the timescales over which spines may record this information, we measured spine growth in saguaro cactus over days, months, and years with time-lapse photography, periodic marking, and postbomb radiocarbon dating and then analyzed isotopic variability over these same timescales and compared these measurements to local climate. We used daily increments of growth, visible as transverse bands of light and dark tissue in spines, as chronometers to develop ...


Long-Term Spatial And Temporal Variability Of Benthic Macroinvertebrate Communities: Implications For Bioassessment Of Lotic Systems, Eve O'Connor 2010 Virginia Commonwealth University

Long-Term Spatial And Temporal Variability Of Benthic Macroinvertebrate Communities: Implications For Bioassessment Of Lotic Systems, Eve O'Connor

Theses and Dissertations

The structure and composition of benthic macroinvertebrate communities can vary spatially and over time. Spatial and temporal variation along a stream has many implications for population and community dynamics, which may influence bioassessment programs. I examined variability in the benthic community of eight streams within the Polecat Creek, Virginia watershed. These streams vary in size from 1st to 4th order. The streams were sampled once every season for eleven years using standard bioassessment protocols. Macroinvertebrates were sampled from both sediment and submerged wood habitats at each site. The coefficient of variation (CV) was used to quantify among season, among year ...


Role Of Neutrophils In Enhancing Vascular Reactivity To Angiotensin Ii In Preeclampsia, Nikita Mishra 2010 Virginia Commonwealth University

Role Of Neutrophils In Enhancing Vascular Reactivity To Angiotensin Ii In Preeclampsia, Nikita Mishra

Theses and Dissertations

Women with preeclampsia have enhanced vascular reactivity to Angiotensin II (Ang II) and extensive vascular infiltration of neutrophils. The primary mechanism to enhance vessel reactivity is RhoA kinase that phosphorylates MYPT1 to inhibit myosin light chain (MLC) phosphatase. Therefore, MLCs remain phosphorylated and increase sensitivity to calcium. Neutrophils release reactive oxygen species (ROS), which can activate this pathway, so we hypothesized that neutrophils would enhance vessel reactivity to Ang II. Omental vessels from normal pregnant women were used to study vascular reactivity. Ang II dose response (0.001-10µM) was significantly enhanced with perfusion of neutrophils (<2000/mm3, activated with IL-8) or ROS. Addition of superoxide dismutase (SOD)/Catalase to quench ROS or 3µM Y-27632, a specific RhoA kinase inhibitor, blocked enhancement. Vascular smooth muscle expression of pMYPT1 and pMLC in cell culture was significantly increased by neutrophils or ROS. The increase was prevented by Y-27632. RhoA kinase activity assay showed a 3-fold increase in RhoA kinase activity in omental vessels treated with ROS. Similarly, ROS also enhanced vessel reactivity to another vasoconstrictor, norepinephrine, via RhoA kinase. In preeclamptic women, increased neutrophil infiltration is associated with increased vascular expression and production of matrix metalloproteinase-1 (MMP-1). MMP-1 activates protease activated receptor-1 (PAR-1), which could cause endothelial endothelin-1 release, so we considered a novel hypothesis that MMP-1 might cause vasoconstriction and enhance vessel reactivity to Ang II via PAR-1. Omental vessels perfused with activated MMP-1 (0.025-25ng/ml) showed dose-dependent vasoconstriction. Perfusion of activated MMP-1 (2.5ng/ml) significantly enhanced dose response to angiotensin II. MMP-1 mediated vasoconstriction and enhanced vessel reactivity to Ang II was abolished by co-perfusion of 10µM SCH-79797, a specific PAR-1 blocker, and by 5µM BQ-123, a specific endothelin-1 type A receptor blocker. These data are the first to show that activated neutrophils enhance vascular reactivity to Ang II via ROS and the RhoA kinase pathway. They are also the first to show that MMP-1 induces vasoconstriction and enhances vessel reactivity to Ang II. Thus, vascular neutrophil infiltration leading to ROS and MMP-1 generation could be an important mechanism for hypertension in preeclampsia.


Comparison Of The Dielectric Response Obtained From Fluorescence Upconversion Measurements And Molecular Dynamics Simulations For Coumarin 153−Apomyoglobin Complexes And Structural Analysis Of The Complexes By Nmr And Fluorescence Methods, Sayantan Bose, Ramkrishna Adhikary, Charles A. Barnes, D. Bruce Fulton, Mark S. Hargrove, Xueyu Song, Jacob W. Petrich 2010 Iowa State University

Comparison Of The Dielectric Response Obtained From Fluorescence Upconversion Measurements And Molecular Dynamics Simulations For Coumarin 153−Apomyoglobin Complexes And Structural Analysis Of The Complexes By Nmr And Fluorescence Methods, Sayantan Bose, Ramkrishna Adhikary, Charles A. Barnes, D. Bruce Fulton, Mark S. Hargrove, Xueyu Song, Jacob W. Petrich

Chemistry Publications

We present a comparison of the dielectric response obtained from fluorescence upconversion experiments and from molecular dynamics simulations of the complexes of coumarin 153 with five apomyoglobins (apoMbs): wild-type horse heart (HH-WT) and those of wild-type sperm whale (SW-WT); its two triple mutants, L29F/H64Q/V68F and H64L/V68F/P88A; and its double mutant, L29F/V68L. Comparisons between experimental and simulated solvation relaxation functions, C(t)s, for the wild-type proteins range from very good to excellent. For the three mutants we investigated, however, agreement between experiment and simulation was considerably inferior. Thus, an NMR study of the complex of ...


Scribble: A Potential Dual Kinase Inhibitor, Steven Christofakis 2010 Virginia Commonwealth University

Scribble: A Potential Dual Kinase Inhibitor, Steven Christofakis

Theses and Dissertations

Extracellular signal-regulated kinases (ERKs) modulate cellular activities in response to extracellular stimuli and play important biological roles. Thus, perturbed kinase pathways induce pathological conditions, such as tumor development. Rit, a novel member of the Ras family GTPases, activase ERK6, and its over-expression confers tumorigenicity. We hypothesized the presence of scaffolding molecules specific to ERK6, similar to other known MAP kinases. We performed yeast two-hybrid assays using ERK6 as bait, and Scribble was identified as a binding partner. Scribble contains 16 LRR domains and four PDZ domains. We performed immunoprecipitation (IP) assays and discovered ERK2 as another binding partner. Surprisingly, no ...


The Development Of A Novel Multi-Dimensional Product For Wound Healing Applications, Necrisha Roach 2010 Virginia Commonwealth University

The Development Of A Novel Multi-Dimensional Product For Wound Healing Applications, Necrisha Roach

Theses and Dissertations

A characteristic feature of chronic wounds is a prolonged inflammatory response as well as susceptibility to infection. Studies have shown that during the inflammatory response, there is a significant increase in the levels of neutrophil-derived enzymes. The purpose of this work was to determine whether the anionic macromolecule polystyrene sulfonate (PSS) and five of its salt forms, namely PSS-calcium, PSS-chlorhexidine, PSS-doxycycline, PSS-glutathione and PSS-silver are able to inhibit the activity of three of the enzymes whose levels are elevated in chronic wounds: elastase, cathepsin G and myeloperoxidase. In addition to the enzyme inhibition study, the various formulations’ antimicrobial properties were ...


Effect Of Visual Input On Vowel Production In English Speakers, Amanda C. Richardson 2010 Macalester College

Effect Of Visual Input On Vowel Production In English Speakers, Amanda C. Richardson

Linguistics Honors Projects

This study analyzes whether there should be a visual component to a model of speech perception and production by comparing the jaw opening, advancement, and rounding of American English and non-English vowels in the presence and absence of a visual stimulus. Surprisingly, jaw opening did not change production, but the presence of the visual stimulus was found to be a significant factor in participants’ vowel advancement for non-English vowels. This may be explained by lip rounding, but requires further research in order to develop a full understanding of the impact of visual input on vowel production to be used in ...


Absence Of Mouse 2b4 Promotes Nk Cell-Mediated Killing Of Activated Cd8+ T Cells, Leading To Prolonged Viral Persistence And Altered Pathogenesis, Stephen N. Waggoner, Ruth T. Taniguchi, Porunelloor A. Mathew, Vinay Kumar, Raymond M. Welsh 2010 University of Massachusetts Medical School

Absence Of Mouse 2b4 Promotes Nk Cell-Mediated Killing Of Activated Cd8+ T Cells, Leading To Prolonged Viral Persistence And Altered Pathogenesis, Stephen N. Waggoner, Ruth T. Taniguchi, Porunelloor A. Mathew, Vinay Kumar, Raymond M. Welsh

Open Access Articles

Persistent viral infections are often associated with inefficient T cell responses and sustained high-level expression of inhibitory receptors, such as the NK cell receptor 2B4 (also known as CD244), on virus-specific T cells. However, the role of 2B4 in T cell dysfunction is undefined, and it is unknown whether NK cells contribute to regulation of these processes. We show here that persistent lymphocytic choriomeningitis virus (LCMV) infection of mice lacking 2B4 resulted in diminished LCMV-specific CD8+ T cell responses, prolonged viral persistence, and spleen and thymic pathologies that differed from those observed in infected wild-type mice. Surprisingly, these altered phenotypes ...


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