oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 54 )

2018 ( 338 )

2017 ( 314 )

2016 ( 490 )

Custom range...

Search Results: 1 - 10 of 302271 matches for " Edward J; "
All listed articles are free for downloading (OA Articles)
Page 1 /302271
Display every page Item
Growth and Toxin Production by Microcystis Aeruginosa PCC 7806 (Kutzing) Lemmerman at Elevated Salt Concentrations  [PDF]
Ken Black, Mete Yilmaz, Edward J. Phlips
Journal of Environmental Protection (JEP) , 2011, DOI: 10.4236/jep.2011.26077
Abstract: One of the most common and widespread bloom-forming cyanobacteria associated with toxin production is Microcystis aeruginosa (Kutzing) Lemmerman. While normally associated with fresh water environments, this toxigenic species has been observed at bloom concentrations in a number of major estuaries worldwide. This study examined the effect of salinity on growth and toxin production by M. aeruginosa strain PCC 7806 under controlled laboratory conditions. Salt concentrations above 12.6 ppt resulted in total cessation of growth. Toxin production was similarly affected, with cultures grown in salt concentrations of 4.6 ppt and above yielding less toxin than the control after 20 days of culture. Toxin concentrations after 20 days of culture were 40% of the control at 4.6 ppt. The relative proportion of extracellular to intracellular toxin increased over time in cultures with salt concentrations greater than 4.6 ppt. Extracellular toxins persisted in the media long after the cessation of growth. The results suggest that the influence of M. aeruginosa and/or its toxins can extend well out into estuarine environments under the influence of significant freshwater inputs.
Aged rat heart: Modulation of age-related respiratory defects decreases ischemic-reflow injury  [PDF]
Edward J. Lesnefsky, Charles L. Hoppel
Health (Health) , 2013, DOI: 10.4236/health.2013.51001
Abstract:

Myocardial injury increases in the elderly heart during ischemia and reperfusion. Mitochondria, the key targets and sources of injury during ischemia and reperfusion, sustain ischemic damage to the electron transport chain that is superimposed upon age-related defects. In the adult heart, interventions to activate endogenous cytoprotective signaling systems meet in mitochondria to decrease cardiac injury. Unfortunately, these systems are largely ineffective in the aged heart. Thus, new treatment concepts are needed to reduce injury in the aged heart. Our group chose a strategy to directly treat the effector of cardiac injury in the aged heart, the mitochondria. We further utilized a novel approach to ask if the reversal of aging defects in cardiac mitochondria before ischemia could decrease ischemia-reperfusion injury in the heart. Three hours following treatment with the small molecule, nutriceutical acetylcarnitine (AcCN), oxidative phosphorylation as well as age-induced defects in electron transport chain complexes III and IV was corrected in the heart. When such hearts were then exposed to ischemia and reperfusion, cardiac injury was markedly reduced. Contraction during reperfusion improved and recovery became similar to that in adult hearts. Cardiac cell death was substantially reduced. Thus, age-related defects in electron transport are a key mechanism of the increased myocardial injury in the elderly heart during ischemia and reperfusion. Modulation of aging-induced defects in mitochondrial metabolism reduces cardiac injury from ischemia and reperfusion, and is a novel strategy to protect myocardium in the elderly patient at risk for an acute myocardial infarction.

Response of Nitrous Oxide Flux to Addition of Anecic Earthworms to an Agricultural Field  [PDF]
José A. Amador, Edward J. Avizinis
Open Journal of Soil Science (OJSS) , 2013, DOI: 10.4236/ojss.2013.32011
Abstract:

The burrowing and feeding activities of earthworms may have a strong effect on the flux of N2O from agricultural soils. As such, shifts to agricultural management practices that increase the number of earthworms require an understanding of the role of earthworms in N2O dynamics. We conducted a field experiment to examine the effects of addition of anecic earthworms (Lumbricus terrestris) on N2O flux in a field previously planted with corn (Zea mays) in southern Rhode Island, USA. Plots were amended with (15NH4)2SO4 and either 0 (CTL) or 48 L. terrestris m-2 (EW). The flux of N2O, 15N2O and 15N2 was measured over 28 days between October and November 2008. The EW treatment had a significantly higher flux of N2O and 15N2O 1 - 3 days after 15NH4 addition. No treatment effects were observed on 15N2 flux. The addition of earthworms significantly increased (Day 1) and decreased (Day 12) the mole fraction of N2O relative to the CTL. Our results suggest that anecic earthworm additions can increase N2O flux from inorganic fertilizer N amendments, but the effects appear to short-lived.

The Molecular Mechanisms of Anesthetic Action: Updates and Cutting Edge Developments from the Field of Molecular Modeling
Edward J. Bertaccini
Pharmaceuticals , 2010, DOI: 10.3390/ph3072178
Abstract: For over 160 years, general anesthetics have been given for the relief of pain and suffering. While many theories of anesthetic action have been purported, it has become increasingly apparent that a significant molecular focus of anesthetic action lies within the family of ligand-gated ion channels (LGIC’s). These protein channels have a transmembrane region that is composed of a pentamer of four helix bundles, symmetrically arranged around a central pore for ion passage. While initial and some current models suggest a possible cavity for binding within this four helix bundle, newer calculations postulate that the actual cavity for anesthetic binding may exist between four helix bundles. In either scenario, these cavities have a transmembrane mode of access and may be partially bordered by lipid moieties. Their physicochemical nature is amphiphilic. Anesthetic binding may alter the overall motion of a ligand-gated ion channel by a “foot-in-door” motif, resulting in the higher likelihood of and greater time spent in a specific channel state. The overall gating motion of these channels is consistent with that shown in normal mode analyses carried out both in vacuo as well as in explicitly hydrated lipid bilayer models. Molecular docking and large scale molecular dynamics calculations may now begin to show a more exact mode by which anesthetic molecules actually localize themselves and bind to specific protein sites within LGIC’s, making the design of future improvements to anesthetic ligands a more realizable possibility.
Correction: System Dynamics Modeling of Individual Transferable Quota Fisheries and Suggestions for Rebuilding Stocks, Sustainability 2011, 3, 184-215
Edward J. Garrity
Sustainability , 2012, DOI: 10.3390/su4092051
Abstract: The author wishes to make the following correction to this paper. Due to mislabeling, replace: [...]
Tragedy of the Commons, Business Growth and the Fundamental Sustainability Problem
Edward J. Garrity
Sustainability , 2012, DOI: 10.3390/su4102443
Abstract: This paper reviews the major issues involved in Hardin’s [1] tragedy of the commons, written over 44 years ago, and examines whether these issues are still relevant today. We assert that this model still provides important insight to aid in the solution to our global problems. In particular, we maintain that the underlying issues of growth against limits and bounded rationality are still not adequately recognized and addressed; this underlies many of the reasons for our unsustainable world. Examples from fisheries management are used to examine potential solutions and reveal weaknesses in current approaches. We show how our current, restricted mental models promote social injustice and blind us to developing sustainable solutions. Both the neo-liberal economic view of business that directly seeks growth and the new sustainable development view that indirectly supports growth are leading our global economy in the wrong direction and away from prosperity and sustainability. Current thinking has not realized Hardin’s message that sustainability is of the class of no technology solution problems. We conclude with recommendations to radically advance a new world view and business paradigm.
System Dynamics Modeling of Individual Transferable Quota Fisheries and Suggestions for Rebuilding Stocks
Edward J. Garrity
Sustainability , 2011, DOI: 10.3390/su3010184
Abstract: This paper develops a system dynamics model of Individual Transferable Quota (ITQ) systems in order to differentiate ITQ from total allowable catch (TAC) effects and to identify areas where policy changes and management improvement may be most effective. ITQ systems provide incentives for long-term stewardship but when fisheries are managed “at the edge,” the incentives are inadequate for stock rebuilding. The free-market design of ITQ systems means that fishermen may be in conflict with the long-run, public sustainability goals of fishery management. An adaptive control scheme with a contingent public/private transfer payment is proposed to improve long-term results for both the local community and the general public.
Are Drosophila telomeres an exception or the rule?
Edward J Louis
Genome Biology , 2002, DOI: 10.1186/gb-2002-3-10-reviews0007
Abstract: The concept of telomeres was first conceived in studies of irradiated Drosophila: Muller [1] found that X-ray-induced chromosomal rearrangements never resulted in loss of the terminal regions of the chromosomes. This observation, along with those of McClintock [2], led to the idea that the ends of chromosomes, or telomeres, must be different from the ends found at breaks in chromosomes, which are not protected from further detrimental rearrangements. Once the structure of DNA was determined and the properties of DNA replication were worked out, Olovnikov [3,4] and Watson [5] recognized that the normal replication machinery could not complete the replication of the ends of double-stranded DNA. We now know that most organisms replicate their chromosome ends using a special reverse transcriptase-like enzyme, called telomerase [6], which uses an RNA template. The repeated telomere sequences, templated by telomerase, perform two important roles in chromosome biology: they solve the end-protection problem, by 'capping' chromosome ends and they solve the end-replication problem, by adding templated sequence.Drosophila telomeres are intriguing for a number of reasons because they appear to break the two cardinal rules of telomeres. First of all, telomere maintenance in Drosophila is not performed by the canonical telomerase but by a unique transposition mechanism. Two non-LTR (long terminal repeat) retrotransposable elements, HeT-A and TART telomere-associated retrotransposons, are attached specifically to the chromosome ends [7,8,9,10]. To date these are the only transposable elements that are known to perform a useful function for the host organism. Perhaps more important is that truncated Drosophila telomeres can be maintained and passed on both somatically and through the germ line, despite their progressive erosion over generations in the absence of HeT-A or TART elements [11,12,13]. This observation is in apparent contradiction to the primary end-protection or capping
Review of Biomedical Image Processing
Edward J Ciaccio
BioMedical Engineering OnLine , 2011, DOI: 10.1186/1475-925x-10-101
Abstract: Biomedical Image Processing, by Thomas M. Deserno [1], is a text that is suitable for clinicians, scientists, and engineers interested in the important topic of how clinical and biomedical images can best be processed for features quantification, and to enhance important visual detail. It is compiled from the notes of multiple authors, all eminent scientists in their field of research. The book is 'all-in-one' in the sense that it can be used as the sole textbook for coursework on this topic, consisting of chapters devoted to image formation and enhancement, feature extraction and selection, image segmentation and classification of features, data visualization, image management and integration, and evaluation and customizing of processing methods.The book begins with an introductory chapter by the editor which includes foundational material, followed by 22 chapters written by experts in biomedical image processing. Each chapter begins with an introductory paragraph, and includes an overview of developments in the particular area of research. Case examples are provided to reinforce the concepts.One problem with books having multiply authored chapters is that they often lack cohesion. However, in this text, many of the chapters build upon information from prior chapters. The flow from one chapter to the next is therefore quite satisfactory. This was enabled in part by the editor providing his written introductory chapter to each of the authors as a guide, as he explains in the Preface. The authors then followed with a broadcast to the group of their proposed chapter outline and contents. This enabled cohesion in form, style, and content between the writings of each author.The chapters are directed at both students and professors. The aim of each chapter is to cover recent advances and to provide up-to-date information, which is done well. Many of the citations at the end of each chapter are from recent work published in the literature. Related textbooks are also provi
Book review of applied medical image processing: A basic course
Edward J Ciaccio
BioMedical Engineering OnLine , 2011, DOI: 10.1186/1475-925x-10-16
Abstract: 'Applied Medical Image Processing: A Basic Course' by Dr. Wolfgang Birkfellner is an outstanding work that will be of interest to virtually all biomedical engineers. Just published by CRC Press and in its first printing in 2011, it is not expensive - listed as $69.95 and available in hardcover. Although 403 pages in length, it is small in footprint and can readily be carried in the pocket of a book or computer bag. The text is easy to follow, supposing only that the reader has a modest knowledge of linear algebra, basic engineering principles, and computer programming.I was impressed by the content as well as by the amount of information that is packed on each page. In each well-organized chapter, important concepts and definitions are described concisely and well. Relevant medical images used for processing compliment many of the concepts discussed. Where important, the mathematical formulation is provided. The text and images refer to several MATLAB-based programming examples that are provided at the end of each chapter. These are useful to apply the concepts to actual medical image processing. The book can be used in part as an excellent reference work for biomedical engineers, scientists, and clinicians.This is a well-written, coherent, and comprehensive work covering the major topics in the field, suitable as a standalone text for coursework in medical image processing. It will mainly be of interest to course directors as an upper-level undergraduate or beginning graduate main textbook. For teaching upper-level undergraduates, the concepts presented can be supplemented with additional programming examples. For teaching beginning graduate students, the text should be supplemented with additional theoretical background in the lectures, as well as more challenging programming examples. For medical residents, lectures in the fundamental mathematics, engineering, and computer language principles may be needed prior to coverage of the image processing chapters. In Ch
Page 1 /302271
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.