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Sample records for mechanics an overview

  1. Signal transduction mechanisms in plants: an overview

    NASA Technical Reports Server (NTRS)

    Clark, G. B.; Thompson, G. Jr; Roux, S. J.

    2001-01-01

    This article provides an overview on recent advances in some of the basic signalling mechanisms that participate in a wide variety of stimulus-response pathways. The mechanisms include calcium-based signalling, G-protein-mediated-signalling and signalling involving inositol phospholipids, with discussion on the role of protein kinases and phosphatases interspersed. As a further defining feature, the article highlights recent exciting findings on three extracellular components that have not been given coverage in previous reviews of signal transduction in plants, extracellular calmodulin, extracellular ATP, and integrin-like receptors, all of which affect plant growth and development.

  2. An overview of mechanisms of redox signaling

    PubMed Central

    Forman, Henry Jay; Ursini, Fulvio; Maiorino, Matilde

    2014-01-01

    A principal characteristic of redox signaling is that it involves an oxidation-reduction reaction or covalent adduct formation between the sensor signaling protein and second messenger. Non-redox signaling may involve alteration of the second messenger as in hydrolysis of GTP by G proteins, modification of the signaling protein as in farnesylation, or simple non-covalent binding of an agonist or second messenger. The chemistry of redox signaling is reviewed here. Specifically we have described how among the so-called reactive oxygen species, only hydroperoxides clearly fit the role of a second messenger. Consideration of reaction kinetics and cellular location strongly suggests that for hydroperoxides, particular protein cysteines are the targets and that the requirements for redox signaling is that these cysteines are in microenvironments in which the cysteine is ionized to the thiolate, and a proton can be donated to form a leaving group. The chemistry described here is the same as occurs in the cysteine and selenocysteine peroxidases that are generally considered the primary defense against oxidative stress. But, these same enzymes can also act as the sensors and transducer for signaling. Conditions that would allow specific signaling by peroxynitrite and superoxide are also defined. Signaling by other electrophiles, which includes lipid peroxidation products, quinones formed from polyphenols and other metabolites also involves reaction with specific protein thiolates. Again, kinetics and location are the primary determinants that provide specificity required for physiological signaling although enzymatic catalysis is not likely involved. PMID:24512843

  3. AN OVERVIEW OF THE SNS ACCELERATOR MECHANICAL ENGINEERING.

    SciTech Connect

    HSEUH, H.; LUDWIG, H.; MAHLER, G.; PAI, C.; PEARSON, C.; RANK, J.; TUOZZOLO, J.; WEI, J.

    2006-06-23

    The Spallation Neutron Source (SNS*) is an accelerator-based neutron source currently nearing completion at Oak Ridge National Laboratory. When completed in 2006, the SNS will provide a 1 GeV, 1.44 MW proton beam to a liquid mercury target for neutron production. SNS is a collaborative effort between six U.S. Department of Energy national laboratories and offered a unique opportunity for the mechanical engineers to work with their peers from across the country. This paper presents an overview of the overall success of the collaboration concentrating on the accelerator ring mechanical engineering along with some discussion regarding the relative merits of such a collaborative approach. Also presented are a status of the mechanical engineering installation and a review of the associated installation costs.

  4. Mechanisms of biological effects of radiofrequency electromagnetic fields: an overview

    SciTech Connect

    Erwin, D.N.

    1988-11-01

    Manmade sources of electromagnetic (EM) fields, and therefore human exposures to them, continue to increase. Public concerns stem from the effects reported in the literature, the visibility of the sources, and somewhat from confusion between EM fields and ionizing radiation. Protecting humans from the real hazards and allaying groundless fears requires a self-consistent body of scientific data concerning effects of the fields, levels of exposures which cause those effects, and which effects are deleterious (or beneficial or neutral). With that knowledge, appropriate guidelines for safety can be devised, while preserving the beneficial uses of radiofrequency radiation (RFR) energy for military or civilian purposes. The task is monumental because of the large and growing number of biological endpoints and the infinite array of RFR exposure conditions under which those endpoints might be examined. The only way to reach this goal is to understand the mechanisms by which EM fields interact with tissues. As in other fields of science, a mechanistic understanding of RFR effects will enable scientists to generalize from a selected few experiments to derive the laws of RFR bioeffects. This article gives an overview of present knowledge of those mechanisms and the part that the USAF School of Aerospace Medicine has played in expanding that knowledge. 91 references.

  5. An Overview of the Molecular Mechanisms of Recombinational DNA Repair.

    PubMed

    Kowalczykowski, Stephen C

    2015-11-01

    Recombinational DNA repair is a universal aspect of DNA metabolism and is essential for genomic integrity. It is a template-directed process that uses a second chromosomal copy (sister, daughter, or homolog) to ensure proper repair of broken chromosomes. The key steps of recombination are conserved from phage through human, and an overview of those steps is provided in this review. The first step is resection by helicases and nucleases to produce single-stranded DNA (ssDNA) that defines the homologous locus. The ssDNA is a scaffold for assembly of the RecA/RAD51 filament, which promotes the homology search. On finding homology, the nucleoprotein filament catalyzes exchange of DNA strands to form a joint molecule. Recombination is controlled by regulating the fate of both RecA/RAD51 filaments and DNA pairing intermediates. Finally, intermediates that mature into Holliday structures are disjoined by either nucleolytic resolution or topological dissolution. PMID:26525148

  6. Autonomous Mechanical Assembly on the Space Shuttle: An Overview

    NASA Technical Reports Server (NTRS)

    Raibert, M. H.

    1979-01-01

    The space shuttle will be equipped with a pair of 50 ft. manipulators used to handle payloads and to perform mechanical assembly operations. Although current plans call for these manipulators to be operated by a human teleoperator. The possibility of using results from robotics and machine intelligence to automate this shuttle assembly system was investigated. The major components of an autonomous mechanical assembly system are examined, along with the technology base upon which they depend. The state of the art in advanced automation is also assessed.

  7. The Antiviral Activities and Mechanisms of Marine Polysaccharides: An Overview

    PubMed Central

    Wang, Wei; Wang, Shi-Xin; Guan, Hua-Shi

    2012-01-01

    Recently, the studies on the antiviral activities of marine natural products, especially marine polysaccharides, are attracting more and more attention all over the world. Marine-derived polysaccharides and their lower molecular weight oligosaccharide derivatives have been shown to possess a variety of antiviral activities. This paper will review the recent progress in research on the antiviral activities and the mechanisms of these polysaccharides obtained from marine organisms. In particular, it will provide an update on the antiviral actions of the sulfated polysaccharides derived from marine algae including carrageenans, alginates, and fucans, relating to their structure features and the structure–activity relationships. In addition, the recent findings on the different mechanisms of antiviral actions of marine polysaccharides and their potential for therapeutic application will also be summarized in detail. PMID:23235364

  8. An Overview of the Mechanical Integrity of Dental Implants

    PubMed Central

    Shemtov-Yona, Keren; Rittel, Daniel

    2015-01-01

    With the growing use of dental implants, the incidence of implants' failures grows. Late treatment complications, after reaching full osseointegration and functionality, include mechanical failures, such as fracture of the implant and its components. Those complications are deemed severe in dentistry, albeit being usually considered as rare, and therefore seldom addressed in the clinical literature. The introduction of dental implants into clinical practice fostered a wealth of research on their biological aspects. By contrast, mechanical strength and reliability issues were seldom investigated in the open literature, so that most of the information to date remains essentially with the manufacturers. Over the years, implants have gone through major changes regarding the material, the design, and the surface characteristics aimed at improving osseointegration. Did those changes improve the implants' mechanical performance? This review article surveys the state-of-the-art literature about implants' mechanical reliability, identifying the known causes for fracture, while outlining the current knowledge-gaps. Recent results on various aspects of the mechanical integrity and failure of implants are presented and discussed next. The paper ends by a general discussion and suggestions for future research, outlining the importance of mechanical considerations for the improvement of their future performance. PMID:26583117

  9. An Overview of Snow Photochemistry: Evidence, Mechanisms and Impacts

    NASA Technical Reports Server (NTRS)

    Grannas, A. M.; Jones, A. E.; Dibb, J.; Ammann, M.; Anastasio, C.; Beine, H. J.; Bergin, M.; Bottenheim, J.; Boxe, C. S.; Carver, G.; Chen, G.; Crawford, J. H.; Domine, F.; Frey, M. M.; Guzman, M. I.; Heard, D. E.; Helmig, D.; Hoffmann, M. R.; Honrath, R. E.; Huey, L. G.; Hutterli, M.; Jacobi, H.-W.; Klan, P.; McConnell, J.; Plane, J.

    2007-01-01

    It has been shown that sunlit snow and ice plays an important role in processing atmospheric species. Photochemical production of a variety of chemicals has recently been reported to occur in snow/ice and the release of these photochemically generated species may significantly impact the chemistry of the overlying atmosphere. Nitrogen oxide and oxidant precursor fluxes have been measured in a number of snow covered environments, where in some cases the emissions significantly impact the overlying boundary layer. For example, photochemical ozone production (such as that occurring in polluted mid-latitudes) of 3-4 ppbv/day has been observed at South Pole, due to high OH and NO levels present in a relatively small boundary layer. Field and laboratory experiments have determined that the origin of the observed NOx flux is the photochemistry of nitrate within the snowpack, however some details of the mechanism have not yet been elucidated. A variety of low molecular weight organic compounds have been shown to be emitted from sunlit snowpacks, the source of which has been proposed to be either direct or indirect photo-oxidation of natural organic materials present in the snow. Although myriad studies have observed active processing of species within irradiated snowpacks, the fundamental chemistry occurring remains poorly understood. Here we consider the nature of snow at a fundamental, physical level; photochemical processes within snow and the caveats needed for comparison to atmospheric photochemistry; our current understanding of nitrogen, oxidant, halogen and organic photochemistry within snow; the current limitations faced by the field and implications for the future.

  10. An Overview of Genetic Mechanisms in the Bacterial Cell.

    ERIC Educational Resources Information Center

    Metcalfe, Judith; Baumberg, Simon

    1988-01-01

    Outlines the genetic elements found in the bacterial cell which play a role in recombining DNA sequences. Provides a core structure to which the mechanisms occurring in and between bacterial cells can be related. Discusses the practicalities of recombinant DNA techniques. (Author/CW)

  11. An overview of reliability methods in mechanical and structural design

    NASA Technical Reports Server (NTRS)

    Wirsching, P. H.; Ortiz, K.; Lee, S. J.

    1987-01-01

    An evaluation is made of modern methods of fast probability integration and Monte Carlo treatment for the assessment of structural systems' and components' reliability. Fast probability integration methods are noted to be more efficient than Monte Carlo ones. This is judged to be an important consideration when several point probability estimates must be made in order to construct a distribution function. An example illustrating the relative efficiency of the various methods is included.

  12. Tribology and Mechanical Components Branch Overview

    NASA Technical Reports Server (NTRS)

    Handschuh, Robert F.

    2010-01-01

    An overview of NASA Glenn Research Center's Tribology & Mechanical Components Branch is provided. Work in space mechanisms, seals, oil-free turbomachinery, and mechanical components is presented. An overview of current research for these technology areas is contained in this overview.

  13. An Overview of Molecular Mechanism of Nephrotic Syndrome

    PubMed Central

    Machado, Juliana Reis; Rocha, Laura Penna; Neves, Precil Diego Miranda de Menezes; Cobô, Eliângela de Castro; Silva, Marcos Vinícius; Castellano, Lúcio Roberto; Corrêa, Rosana Rosa Miranda; Reis, Marlene Antônia

    2012-01-01

    Podocytopathies (minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS)) together with membranous nephropathy are the main causes of nephrotic syndrome. Some changes on the expression of nephrin, podocin, TGF-β, and slit diaphragm components as well as transcription factors and transmembrane proteins have been demonstrated in podocytopathies. Considering the pathogenesis of proteinuria, some elucidations have been directed towards the involvement of epithelial-mesenchymal transition. Moreover, the usefulness of some markers such as TGF-β1, nephrin, synaptopodin, dystroglycans, and malondialdehyde have been determined in the differentiation between MCD and FSGS. Experimental models and human samples indicated an essential role of autoantibodies in membranous glomerulonephritis, kidney damage, and proteinuria events. Megalin and phospholipase-A2-receptor have been described as antigens responsible for the formation of the subepithelial immune complexes and renal disease occurrence. In addition, the complement system seems to play a key role in basal membrane damage and in the development of proteinuria in membranous nephropathy. This paper focuses on the common molecular changes involved in the development of nephrotic proteinuria. PMID:22844593

  14. Self-assembled and pyrolyzed carbon aerogels: an overview of their preparation mechanisms, properties and applications

    NASA Astrophysics Data System (ADS)

    Allahbakhsh, Ahmad; Bahramian, Ahmad Reza

    2015-08-01

    An overview of the synthesis conditions and mechanisms for the fabrication of different types of carbon aerogels, as well as the structural and functional properties of these materials, is presented here. In this overview, carbon aerogels are classified into three major categories: (i) conventional pyrolyzed organic-based carbon aerogels, which are products of the pyrolysis process of organic aerogels; (ii) self-assembled carbon aerogels, which are products of a reduction process; and (iii) nanocomposite carbon aerogels. Synthesis mechanisms for the sol-gel process of organic aerogels are reviewed using different mechanisms suggested in the literature. Moreover, the overall fabrication process of self-assembled carbon aerogels (graphene and carbon nanotube aerogels) is covered and the suggested mechanism for the gelation process of self-assembled carbon aerogels during the reduction process is investigated using reported mechanisms. The structural performance and functional properties (electrochemical and thermal properties) of different types of carbon aerogels are covered in detail. Moreover, different structural features of carbon aerogels and the influence of synthesis conditions on these structural characteristics are assessed and compared. Based on the literature results covered in this review paper, carbon aerogels are perfect candidates for the fabrication of ultra-low density supercapacitors, as well as thermal insulating materials.

  15. Self-assembled and pyrolyzed carbon aerogels: an overview of their preparation mechanisms, properties and applications.

    PubMed

    Allahbakhsh, Ahmad; Bahramian, Ahmad Reza

    2015-09-14

    An overview of the synthesis conditions and mechanisms for the fabrication of different types of carbon aerogels, as well as the structural and functional properties of these materials, is presented here. In this overview, carbon aerogels are classified into three major categories: (i) conventional pyrolyzed organic-based carbon aerogels, which are products of the pyrolysis process of organic aerogels; (ii) self-assembled carbon aerogels, which are products of a reduction process; and (iii) nanocomposite carbon aerogels. Synthesis mechanisms for the sol-gel process of organic aerogels are reviewed using different mechanisms suggested in the literature. Moreover, the overall fabrication process of self-assembled carbon aerogels (graphene and carbon nanotube aerogels) is covered and the suggested mechanism for the gelation process of self-assembled carbon aerogels during the reduction process is investigated using reported mechanisms. The structural performance and functional properties (electrochemical and thermal properties) of different types of carbon aerogels are covered in detail. Moreover, different structural features of carbon aerogels and the influence of synthesis conditions on these structural characteristics are assessed and compared. Based on the literature results covered in this review paper, carbon aerogels are perfect candidates for the fabrication of ultra-low density supercapacitors, as well as thermal insulating materials. PMID:26245296

  16. Nondestructive techniques for characterizing mechanical properties of structural materials - An overview

    NASA Technical Reports Server (NTRS)

    Vary, A.; Klima, S. J.

    1986-01-01

    An overview of nondestructive evaluation (NDE) is presented to indicate the availability and application potentials of techniques for quantitative characterization of the mechanical properties of structural materials. The purpose is to review NDE techniques that go beyond the usual emphasis on flow detection and characterization. Discussed are current and emerging NDE techniques that can verify and monitor entrinsic properties (e.g., tensile, shear, and yield strengths; fracture toughness, hardness, ductility; elastic moduli) and underlying microstructural and morphological factors. Most of the techniques described are, at present, neither widely applied nor widely accepted in commerce and industry because they are still emerging from the laboratory. The limitations of the techniques may be overcome by advances in applications research and instrumentation technology and perhaps by accommodations for their use in the design of structural parts.

  17. Nondestructive techniques for characterizing mechanical properties of structural materials: An overview

    NASA Technical Reports Server (NTRS)

    Vary, A.; Klima, S. J.

    1985-01-01

    An overview of nondestructive evaluation (NDE) is presented to indicate the availability and application potentials of techniques for quantitative characterization of the mechanical properties of structural materials. The purpose is to review NDE techniques that go beyond the usual emphasis on flaw detection and characterization. Discussed are current and emerging NDE techniques that can verify and monitor entrinsic properties (e.g., tensile, shear, and yield strengths; fracture toughness, hardness, ductility; elastic moduli) and underlying microstructural and morphological factors. Most of the techniques described are, at present, neither widely applied nor widely accepted in commerce and industry because they are still emerging from the laboratory. The limitations of the techniques may be overcome by advances in applications research and instrumentation technology and perhaps by accommodations for their use in the design of structural parts.

  18. An overview of potential molecular mechanisms involved in VSMC phenotypic modulation.

    PubMed

    Zhang, Ming-Jie; Zhou, Yi; Chen, Lei; Wang, Yan-Qin; Wang, Xu; Pi, Yan; Gao, Chang-Yue; Li, Jing-Cheng; Zhang, Li-Li

    2016-02-01

    The fully differentiated medial vascular smooth muscle cells (VSMCs) of mature vessels keep quiescent and contractile. However, VSMC can exhibit the plasticity in phenotype switching from a differentiated and contractile phenotype to a dedifferentiated state in response to alterations in local environmental cues, which is called phenotypic modulation or switching. Distinguishing from its differentiated state expressing more smooth muscle (SM)-specific/selective proteins, the phenotypic modulation in VSMC is characterized by an increased rate of proliferation, migration, synthesis of extracellular matrix proteins and decreased expression of SM contractile proteins. Although it has been well demonstrated that phenotypic modulation of VSMC contributes to the occurrence and progression of many proliferative vascular diseases, little is known about the details of the molecular mechanisms of VSMC phenotypic modulation. Growing evidence suggests that variety of molecules including microRNAs, cytokines and biochemical factors, membrane receptors, ion channels, cytoskeleton and extracellular matrix play important roles in controlling VSMC phenotype. The focus of the present review is to provide an overview of potential molecular mechanisms involved in VSMC phenotypic modulation in recent years. To clarify VSMC differentiation and phenotypic modulation mechanisms will contribute to producing cell-based therapeutic interventions for aberrant VSMC differentiation-related diseases. PMID:26708152

  19. An Overview of Mechanical Properties and Material Modeling of Polylactide (PLA) for Medical Applications.

    PubMed

    Bergström, Jörgen S; Hayman, Danika

    2016-02-01

    This article provides an overview of the connection between the microstructural state and the mechanical response of various bioresorbable polylactide (PLA) devices for medical applications. PLLA is currently the most commonly used material for bioresorbable stents and sutures, and its use is increasing in many other medical applications. The non-linear mechanical response of PLLA, due in part to its low glass transition temperature (T g ≈ 60 °C), is highly sensitive to the molecular weight and molecular orientation field, the degree of crystallinity, and the physical aging time. These microstructural parameters can be tailored for specific applications using different resin formulations and processing conditions. The stress-strain, deformation, and degradation response of a bioresorbable medical device is also strongly dependent on the time history of applied loads and boundary conditions. All of these factors can be incorporated into a suitable constitutive model that captures the multiple physics that are involved in the device response. Currently developed constitutive models already provide powerful computations simulation tools, and more progress in this area is expected to occur in the coming years. PMID:26369638

  20. An overview on internal geared mechanisms with small difference between teeth number

    NASA Astrophysics Data System (ADS)

    Macovei (Cîrdei, S.; Doroftei, I.

    2015-11-01

    Internal gears with small difference between teeth number are most commonly encountered in planetary and differential mechanisms (eg. on automatic transmissions for vehicles). One of the advantages of this gear is the high transmission ratio. Their parallel axes make this gear perfect for the cases when a small deviation of the distance between axes is required. Automatic transmission allows internal gear function to high speed. In this, we present a short overview of internal gear with small difference between teeth number.

  1. An Overview of the Evidence and Mechanisms of Herb–Drug Interactions

    PubMed Central

    Fasinu, Pius S.; Bouic, Patrick J.; Rosenkranz, Bernd

    2012-01-01

    Despite the lack of sufficient information on the safety of herbal products, their use as alternative and/or complementary medicine is globally popular. There is also an increasing interest in medicinal herbs as precursor for pharmacological actives. Of serious concern is the concurrent consumption of herbal products and conventional drugs. Herb–drug interaction (HDI) is the single most important clinical consequence of this practice. Using a structured assessment procedure, the evidence of HDI presents with varying degree of clinical significance. While the potential for HDI for a number of herbal products is inferred from non-human studies, certain HDIs are well established through human studies and documented case reports. Various mechanisms of pharmacokinetic HDI have been identified and include the alteration in the gastrointestinal functions with consequent effects on drug absorption; induction and inhibition of metabolic enzymes and transport proteins; and alteration of renal excretion of drugs and their metabolites. Due to the intrinsic pharmacologic properties of phytochemicals, pharmacodynamic HDIs are also known to occur. The effects could be synergistic, additive, and/or antagonistic. Poor reporting on the part of patients and the inability to promptly identify HDI by health providers are identified as major factors limiting the extensive compilation of clinically relevant HDIs. A general overview and the significance of pharmacokinetic and pharmacodynamic HDI are provided, detailing basic mechanism, and nature of evidence available. An increased level of awareness of HDI is necessary among health professionals and drug discovery scientists. With the increasing number of plant-sourced pharmacological actives, the potential for HDI should always be assessed in the non-clinical safety assessment phase of drug development process. More clinically relevant research is also required in this area as current information on HDI is insufficient for clinical

  2. An Overview of Optimal Endovascular Strategy in Treating the Femoropopliteal Artery: Mechanical, Biological, and Procedural Factors

    PubMed Central

    Shammas, Nicolas W.

    2013-01-01

    Treatment of the femoropopliteal (FP) artery remains a challenge to the endovascular specialist. Long-term patency is low with a high rate of target lesion revascularization. The true patency rate varies considerably between studies partly because there is a lack of uniform performance criteria and reporting standards in peripheral arterial interventions. Literature review supports three principles that emerge as important components of an optimal strategy in treating the FP artery: (1) improving vessel compliance and subsequently less dissections and bailout stenting, (2) reducing smooth muscle cell proliferation, and (3) protecting outflow vessels from distal embolization. In this overview, we examine current data that support the validity of this strategy. PMID:24436577

  3. Osteoporosis: An Overview.

    ERIC Educational Resources Information Center

    Johnston, C. Conrad; Slemenda, Charles

    1987-01-01

    An overview of osteoporosis, its types, causes, diagnosis, and treatment is presented. Risk factors and bone mass measurement are also discussed. This article serves as an introduction to a symposium on osteoporosis containing five other articles in this issue. (MT)

  4. Prion diseases. An overview.

    PubMed

    Dalsgaard, Niels Jørn

    2002-01-01

    Prion disease is the new designation of a group of spongiform encephalopathies, all invariably fatal, which show similar clinical and neuropathological changes. They comprise a range of distinct diseases in both animals and man, and spontaneous, hereditary and transmissible forms are recognized. Until the sudden occurrence in the mid-1980s of an epizootic of a formerly unknown disease, popularly named 'mad cow disease', in cattle in the UK, very little attention had been paid to these rather obscure diseases. Concurrently it was asserted that the disease-causing agent appeared to be a ubiquitous mammalian brain constituent, and the disease mechanism a conformational change of its structure. These events have not only led to a new understanding of these extraordinary diseases, but have also provided insight into both neurodegeneration and disease mechanisms at the molecular level. Moreover, in 1997 the prion concept earned its originator the second Nobel price for medicine within this scientific field. In this introduction and overview of prion diseases, historical and philosophical perspectives are presented along with descriptions of the diseases in both animals and man. Epidemiology, genetics and transmissibility are also covered. PMID:12064253

  5. EPICS system: an overview

    SciTech Connect

    Bartlett, J.F.; Bobbitt, J.S.; Kramper, B.J.; Lahey, T.E.; MacKinnon, B.A.; West, R.E.

    1984-02-01

    This paper presents an overview of the EPICS control system at FERMILAB. EPICS is a distributed, multi-user, interactive system for the control and monitoring of particle beamlines at a high-energy experimental physics laboratory. The overview discusses the operating environment of the control system, the requirements which determined the design decisions, the hardware and software configurations, and plans for the future growth and enhancement of the present system. This paper is the first of three related papers on the EPICS system. The other two cover (1) the system structure and user interface and (2) RSX implementation issues.

  6. Futurism 1984: An Overview.

    ERIC Educational Resources Information Center

    Hood, Florence F.

    This overview of futurism defines it as a movement believing that a positive future world may be created through wise decision-making and futuristic planning. Present societal conditions have provided an impetus for a futuristic focus, and various authors, think tanks, techniques, and organizations have contributed to the wide acclaim and respect…

  7. DIOXINS: AN OVERVIEW

    EPA Science Inventory

    Introduction: Dioxins have been featured in the news recently following a poisoning incident in Europe.1-3 Because physicians are not usually taught much about the dioxins, this article attempts to provide an overview for practicing physicians. Dioxins are unwanted contaminants ...

  8. An Overview of Audacity

    ERIC Educational Resources Information Center

    Thompson, Douglas Earl

    2014-01-01

    This article is an overview of the open source audio-editing and -recording program, Audacity. Key features are noted, along with significant features not included in the program. A number of music and music technology concepts are identified that could be taught and/or reinforced through using Audacity.

  9. An overview of multiphase cartilage mechanical modelling and its role in understanding function and pathology.

    PubMed

    Klika, Václav; Gaffney, Eamonn A; Chen, Ying-Chun; Brown, Cameron P

    2016-09-01

    There is a long history of mathematical and computational modelling with the objective of understanding the mechanisms governing cartilage׳s remarkable mechanical performance. Nonetheless, despite sophisticated modelling development, simulations of cartilage have consistently lagged behind structural knowledge and thus the relationship between structure and function in cartilage is not fully understood. However, in the most recent generation of studies, there is an emerging confluence between our structural knowledge and the structure represented in cartilage modelling. This raises the prospect of further refinement in our understanding of cartilage function and also the initiation of an engineering-level understanding for how structural degradation and ageing relates to cartilage dysfunction and pathology, as well as informing the potential design of prospective interventions. Aimed at researchers entering the field of cartilage modelling, we thus review the basic principles of cartilage models, discussing the underlying physics and assumptions in relatively simple settings, whilst presenting the derivation of relatively parsimonious multiphase cartilage models consistent with our discussions. We proceed to consider modern developments that start aligning the structure captured in the models with observed complexities. This emphasises the challenges associated with constitutive relations, boundary conditions, parameter estimation and validation in cartilage modelling programmes. Consequently, we further detail how both experimental interrogations and modelling developments can be utilised to investigate and reduce such difficulties before summarising how cartilage modelling initiatives may improve our understanding of cartilage ageing, pathology and intervention. PMID:27195911

  10. Plant-derived natural medicines for the management of depression: an overview of mechanisms of action.

    PubMed

    Farahani, Marzieh Sarbandi; Bahramsoltani, Roodabeh; Farzaei, Mohammad Hosein; Abdollahi, Mohammad; Rahimi, Roja

    2015-01-01

    Depression is a serious widespread psychiatric disorder that affects approximately 17% of people all over the world. Exploring the neurological mechanisms of the antidepressant activity of plant-derived agents could have a crucial role in developing natural drugs for the management of depression. The aim of the present study is to review the neurological mechanisms of action of antidepressant plants and their constituents. For this purpose, electronic databases, including PubMed, Science Direct, Scopus, and Cochrane Library, were searched from 1966 to October 2013. The results showed that several molecular mechanisms could be proposed for the antidepressant activity of medicinal plants and their constituents. Hypericum species could normalize brain serotonin level. Liquiritin and isoliquiritin from Glycyrrhiza uralensis rhizome act via the noradrenergic system. Rosmarinus officinalis and curcumin from Curcuma longa interact with D1 and D2 receptors as well as elevate the brain dopamine level. Sida tiagii and Aloysia gratissima involve γ-aminobutyric acid and N-methyl-D-aspartate receptors, respectively. Fuzi polysaccharide-1 from Aconitum carmichaeli could affect brain-derived neurotrophic factor signaling pathways. Psoralidin from Psoralea corylifolia seed modulate the hypothalamic-pituitary-adrenal axis. The total glycosides of Paeonia lactiflora demonstrate an inhibitory effect on both subtypes of monoamine oxidase. 3,6'-Di-o-sinapoyl-sucrose and tenuifoliside A from Polygala tenuifolia exhibit cytoprotective effects on neuronal cells. Further preclinical and clinical trials evaluating their safety, bioefficacy, and bioavailability are suggested to prove the valuable role of natural drugs in the management of depressive disorders. PMID:25719303

  11. An Overview of Combustion Mechanisms and Flame Structures for Advanced Solid Propellants

    NASA Technical Reports Server (NTRS)

    Beckstead, M. W.

    2000-01-01

    Ammonium perchlorate (AP) and cyclotretamethylenetetranitramine (HMX) are two solid ingredients often used in modern solid propellants. Although these two ingredients have very similar burning rates as monopropellants, they lead to significantly different characteristics when combined with binders to form propellants. Part of the purpose of this paper is to relate the observed combustion characteristics to the postulated flame structures and mechanisms for AP and HMX propellants that apparently lead to these similarities and differences. For AP composite, the primary diffusion flame is more energetic than the monopropellant flame, leading to an increase in burning rate over the monopropellant rate. In contrast the HMX primary diffusion flame is less energetic than the HMX monopropellant flame and ultimately leads to a propellant rate significantly less than the monopropellant rate in composite propellants. During the past decade the search for more energetic propellants and more environmentally acceptable propellants is leading to the development of propellants based on ingredients other than AP and HMX. The objective of this paper is to utilize the more familiar combustion characteristics of AP and HMX containing propellants to project the combustion characteristics of propellants made up of more advanced ingredients. The principal conclusion reached is that most advanced ingredients appear to burn by combustion mechanisms similar to HMX containing propellants rather than AP propellants.

  12. Scoliosis quantification: an overview

    PubMed Central

    Kawchuk, Greg; McArthur, Ross

    1997-01-01

    Scoliotic curvatures have long been a focus of attention for clinicians and research scientists alike. The study, treatment and ultimately, the prevention of this prevalent health condition are impeded by the absence of an accurate, reliable, convenient and safe method of scoliosis quantification. The purpose of this paper is to provide an overview of the current methods of scoliosis quantification for clinicians who address this condition in their practices.

  13. An Overview on the Proposed Mechanisms of Antithyroid Drugs-Induced Liver Injury

    PubMed Central

    Heidari, Reza; Niknahad, Hossein; Jamshidzadeh, Akram; Eghbal, Mohammad Ali; Abdoli, Narges

    2015-01-01

    Drug-induced liver injury (DILI) is a major problem for pharmaceutical industry and drug development. Mechanisms of DILI are many and varied. Elucidating the mechanisms of DILI will allow clinicians to prevent liver failure, need for liver transplantation, and death induced by drugs. Methimazole and propylthiouracil (PTU) are two convenient antithyroid agents which their administration is accompanied by hepatotoxicity as a deleterious side effect. Although several cases of antithyroid drugs-induced liver injury are reported, there is no clear idea about the mechanism(s) of hepatotoxicity induced by these medications. Different mechanisms such as reactive metabolites formation, oxidative stress induction, intracellular targets dysfunction, and immune-mediated toxicity are postulated to be involved in antithyroid agents-induced hepatic damage. Due to the idiosyncratic nature of antithyroid drugs-induced hepatotoxicity, it is impossible to draw a specific conclusion about the mechanisms of liver injury. However, it seems that reactive metabolite formation and immune-mediated toxicity have a great role in antithyroids liver toxicity, especially those caused by methimazole. This review attempted to discuss different mechanisms proposed to be involved in the hepatic injury induced by antithyroid drugs. PMID:25789213

  14. Paediatric anaesthesia: an overview.

    PubMed

    Langton, Helen Elizabeth

    2015-10-28

    This article provides an overview of the nursing considerations for paediatric anaesthesia. It is aimed at newly qualified operating department practitioners and anaesthetic nurses, and those with limited experience in the care of paediatric patients. It explores the ways in which paediatric anatomy and physiology differ from those of adults and looks at the implications for treatment in the anaesthetic environment. It also discusses the equipment required and the rationale for its use. PMID:26508256

  15. An overview of vortioxetine.

    PubMed

    Schatzberg, Alan F; Blier, Pierre; Culpepper, Larry; Jain, Rakesh; Papakostas, George I; Thase, Michael E

    2014-12-01

    Six clinicians provide an overview of the serotonergic antidepressant vortioxetine, which was recently approved for the treatment of major depressive disorder in adults. They discuss the pharmacologic profile and receptor-mediated effects of vortioxetine in relation to potential outcomes. Additionally, they summarize the clinical trials, which demonstrate vortioxetine's efficacy, and discuss findings related to safety and tolerability that have high relevance to patient compliance. PMID:25551236

  16. Dopamine dysregulation syndrome: an overview of its epidemiology, mechanisms and management.

    PubMed

    O'Sullivan, Sean S; Evans, Andrew H; Lees, Andrew J

    2009-01-01

    Dopamine dysregulation syndrome (DDS) is a relatively recently described iatrogenic disturbance that may complicate long-term symptomatic therapy of Parkinson's disease. Patients with DDS develop an addictive pattern of dopamine replacement therapy (DRT) use, administering doses in excess of those required to control their motor symptoms. The prevalence of DDS in patients attending specialist Parkinson's disease centres is 3-4%. Amongst the behavioural disturbances associated with DDS are punding, which is a complex stereotyped behaviour, and impulse control disorders (ICDs), such as pathological gambling, hypersexuality, compulsive shopping and compulsive eating. We review the risk factors and potential mechanisms for the development of DDS, including personality traits, potential genetic influences and Parkinson's disease-related cognitive deficits. Impulsive personality traits are prominent in patients developing DDS, and have been previously associated with the development of substance dependence. Candidate genes affecting the dopamine 'D(2)-like' receptor family have been associated with impulsive personality traits in addition to drug and nondrug addictions. Impaired decision making is implicated in addictive behaviours, and decision-making abilities can be influenced by dopaminergic medications. In Parkinson's disease, disruption of the reciprocal loops between the striatum and structures in the prefrontal cortex following dopamine depletion may predispose to DDS. The role of DRT in DDS is discussed, with particular reference to models of addiction, suggesting that compulsive drug use is due to progressive neuroadaptations in dopamine projections to the accumbens-related circuitry. Evidence for neuroadaptations and sensitization occurring in DDS include enhanced levodopa-induced ventral striatal dopamine release. Levodopa is still considered the most potent trigger for DDS in Parkinson's disease, but subcutaneous apomorphine and oral dopamine agonists may

  17. An Overview of Innovative Strategies for Fracture Mechanics at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Ransom, Jonathan B.; Glaessgen, Edward H.; Ratcliffe, James G.

    2010-01-01

    Engineering fracture mechanics has played a vital role in the development and certification of virtually every aerospace vehicle that has been developed since the mid-20th century. NASA Langley Research Center s Durability, Damage Tolerance and Reliability Branch has contributed to the development and implementation of many fracture mechanics methods aimed at predicting and characterizing damage in both metallic and composite materials. This paper presents a selection of computational, analytical and experimental strategies that have been developed by the branch for assessing damage growth under monotonic and cyclic loading and for characterizing the damage tolerance of aerospace structures

  18. An Overview of the Use of Mechanical Turk in Behavioral Sciences: Implications for Social Work

    ERIC Educational Resources Information Center

    Chan, Chitat; Holosko, Michael J.

    2016-01-01

    Crowdsourcing is a process in which a firm parcels out work to a "crowd" and offers payment for anyone within the crowd who completes the task determined by that firm. A growing number of behavioral scientists have begun using the Mechanical Turk (MTurk) to facilitate their research and practice, but there is apparently not one academic…

  19. Gene Silencing and Polycomb Group Proteins: An Overview of their Structure, Mechanisms and Phylogenetics

    PubMed Central

    Majid, Nazia Abdul; Hassandarvish, Pouya; Hajrezaie, Maryam; Abdulla, Mahmood Ameen; Hadi, A. Hamid A.

    2013-01-01

    Abstract DNA methylation, histone modifications, and chromatin configuration are crucially important in the regulation of gene expression. Among these epigenetic mechanisms, silencing the expression of certain genes depending on developmental stage and tissue specificity is a key repressive system in genome programming. Polycomb (Pc) proteins play roles in gene silencing through different mechanisms. These proteins act in complexes and govern the histone methylation profiles of a large number of genes that regulate various cellular pathways. This review focuses on two main Pc complexes, Pc repressive complexes 1 and 2, and their phylogenetic relationship, structures, and function. The dynamic roles of these complexes in silencing will be discussed herein, with a focus on the recruitment of Pc complexes to target genes and the key factors involved in their recruitment. PMID:23692361

  20. Gene silencing and Polycomb group proteins: an overview of their structure, mechanisms and phylogenetics.

    PubMed

    Golbabapour, Shahram; Majid, Nazia Abdul; Hassandarvish, Pouya; Hajrezaie, Maryam; Abdulla, Mahmood Ameen; Hadi, A Hamid A

    2013-06-01

    DNA methylation, histone modifications, and chromatin configuration are crucially important in the regulation of gene expression. Among these epigenetic mechanisms, silencing the expression of certain genes depending on developmental stage and tissue specificity is a key repressive system in genome programming. Polycomb (Pc) proteins play roles in gene silencing through different mechanisms. These proteins act in complexes and govern the histone methylation profiles of a large number of genes that regulate various cellular pathways. This review focuses on two main Pc complexes, Pc repressive complexes 1 and 2, and their phylogenetic relationship, structures, and function. The dynamic roles of these complexes in silencing will be discussed herein, with a focus on the recruitment of Pc complexes to target genes and the key factors involved in their recruitment. PMID:23692361

  1. Molecular and cellular mechanisms of ecstasy-induced neurotoxicity: an overview.

    PubMed

    Capela, João Paulo; Carmo, Helena; Remião, Fernando; Bastos, Maria Lourdes; Meisel, Andreas; Carvalho, Félix

    2009-06-01

    "Ecstasy" [(+/-)-3,4-methylenedioxymethamphetamine, MDMA, XTC, X, E] is a psychoactive recreational hallucinogenic substance and a major worldwide drug of abuse. Several reports raised the concern that MDMA has the ability to induce neurotoxic effects both in laboratory animals and humans. Despite more than two decades of research, the mechanisms by which MDMA is neurotoxic are still to be fully elucidated. MDMA induces serotonergic terminal loss in rats and also in some mice strains, but also a broader neuronal degeneration throughout several brain areas such as the cortex, hippocampus, and striatum. Meanwhile, in human "ecstasy" abusers, there are evidences for deficits in seronergic biochemical markers, which correlate with long-term impairments in memory and learning. There are several factors that contribute to MDMA-induced neurotoxicity, namely, hyperthermia, monoamine oxidase metabolism of dopamine and serotonin, dopamine oxidation, the serotonin transporter action, nitric oxide, and the formation of peroxinitrite, glutamate excitotoxicity, serotonin 2A receptor agonism, and, importantly, the formation of MDMA neurotoxic metabolites. The present review covered the following topics: history and epidemiology, pharmacological mechanisms, metabolic pathways and the influence of isoenzyme genetic polymorphisms, as well as the acute effects of MDMA in laboratory animals and humans, with a special focus on MDMA-induced neurotoxic effects at the cellular and molecular level. The main aim of this review was to contribute to the understanding of the cellular and molecular mechanisms involved in MDMA neurotoxicity, which can help in the development of therapeutic approaches to prevent or treat the long-term neuropsychiatric complications of MDMA abuse in humans. PMID:19373443

  2. Antidepressants as analgesics: an overview of central and peripheral mechanisms of action.

    PubMed Central

    Sawynok, J; Esser, M J; Reid, A R

    2001-01-01

    Antidepressants, given systemically, are widely used for the treatment of various chronic and neuropathic pain conditions in humans. In animal studies, antidepressants exhibit analgesic properties in nociceptive, inflammatory and neuropathic test systems, with outcomes depending on the specific agent, the particular test, the route of administration and the treatment method used. Although early studies focused on central (i.e., supraspinal, spinal) actions, more recent studies have demonstrated a local peripheral analgesic effect of antidepressants. These peripheral actions raise the possibility that topical formulations of antidepressants may be a useful alternative drug delivery system for analgesia. Antidepressants exhibit a number of pharmacological actions: they block reuptake of noradrenaline and 5-hydroxytryptamine, have direct and indirect actions on opioid receptors, inhibit histamine, cholinergic, 5-hydroxytryptamine and N-methyl-D-aspartate receptors, inhibit ion channel activity, and block adenosine uptake. The involvement of these mechanisms in both central and peripheral analgesia produced by antidepressants is considered. Data illustrating the preclinical peripheral analgesic actions of antidepressants are presented, as are some aspects of the mechanisms by which these actions occur. PMID:11212590

  3. Antibacterial Derivatives of Marine Algae: An Overview of Pharmacological Mechanisms and Applications.

    PubMed

    Shannon, Emer; Abu-Ghannam, Nissreen

    2016-04-01

    The marine environment is home to a taxonomically diverse ecosystem. Organisms such as algae, molluscs, sponges, corals, and tunicates have evolved to survive the high concentrations of infectious and surface-fouling bacteria that are indigenous to ocean waters. Both macroalgae (seaweeds) and microalgae (diatoms) contain pharmacologically active compounds such as phlorotannins, fatty acids, polysaccharides, peptides, and terpenes which combat bacterial invasion. The resistance of pathogenic bacteria to existing antibiotics has become a global epidemic. Marine algae derivatives have shown promise as candidates in novel, antibacterial drug discovery. The efficacy of these compounds, their mechanism of action, applications as antibiotics, disinfectants, and inhibitors of foodborne pathogenic and spoilage bacteria are reviewed in this article. PMID:27110798

  4. An Overview of Carcinogenic Heavy Metal: Molecular Toxicity Mechanism and Prevention

    PubMed Central

    Kim, Hyun Soo; Kim, Yeo Jin; Seo, Young Rok

    2015-01-01

    Almost all heavy metals are serious toxicants as carcinogens. However, due to their chemical and physiological properties, heavy metals are useful in industrial areas including alloy, smelting and production of commercial products. Such applications increase the opportunity for heavy metal exposure. Waste from industrial processes is also a major source of environmental contamination and accumulation in the human body. Arsenic, cadmium, chromium, and nickel are classified as group 1 carcinogens by the International Agency for Research on Cancer, and are utilized commercially. In this review, we used molecular pathway analysis to understand the toxicity and carcinogenic mechanisms of these metals. Our analyzed data showed that above-mentioned metallic substances induce oxidative stress, DNA damage, and cell death processes, resulting in increase the risk of cancer and cancer-related diseases. Thus, we might think phytochelatin molecules and antioxidative phytochemical substances are helpful for prevention of heavy metal-induced cancer. PMID:26734585

  5. Antibacterial Derivatives of Marine Algae: An Overview of Pharmacological Mechanisms and Applications

    PubMed Central

    Shannon, Emer; Abu-Ghannam, Nissreen

    2016-01-01

    The marine environment is home to a taxonomically diverse ecosystem. Organisms such as algae, molluscs, sponges, corals, and tunicates have evolved to survive the high concentrations of infectious and surface-fouling bacteria that are indigenous to ocean waters. Both macroalgae (seaweeds) and microalgae (diatoms) contain pharmacologically active compounds such as phlorotannins, fatty acids, polysaccharides, peptides, and terpenes which combat bacterial invasion. The resistance of pathogenic bacteria to existing antibiotics has become a global epidemic. Marine algae derivatives have shown promise as candidates in novel, antibacterial drug discovery. The efficacy of these compounds, their mechanism of action, applications as antibiotics, disinfectants, and inhibitors of foodborne pathogenic and spoilage bacteria are reviewed in this article. PMID:27110798

  6. An Overview of Carcinogenic Heavy Metal: Molecular Toxicity Mechanism and Prevention.

    PubMed

    Kim, Hyun Soo; Kim, Yeo Jin; Seo, Young Rok

    2015-12-01

    Almost all heavy metals are serious toxicants as carcinogens. However, due to their chemical and physiological properties, heavy metals are useful in industrial areas including alloy, smelting and production of commercial products. Such applications increase the opportunity for heavy metal exposure. Waste from industrial processes is also a major source of environmental contamination and accumulation in the human body. Arsenic, cadmium, chromium, and nickel are classified as group 1 carcinogens by the International Agency for Research on Cancer, and are utilized commercially. In this review, we used molecular pathway analysis to understand the toxicity and carcinogenic mechanisms of these metals. Our analyzed data showed that above-mentioned metallic substances induce oxidative stress, DNA damage, and cell death processes, resulting in increase the risk of cancer and cancer-related diseases. Thus, we might think phytochelatin molecules and antioxidative phytochemical substances are helpful for prevention of heavy metal-induced cancer. PMID:26734585

  7. An Overview of the Predictor Standard Tools for Patient Weaning from Mechanical Ventilation

    PubMed Central

    Dehghani, Acieh; Abdeyazdan, Gholamhossein; Davaridolatabadi, Elham

    2016-01-01

    Most patients staying in the intensive care unit (ICU) require respiratory support through a ventilator. Since prolonged mechanical ventilation and weaning from the ventilator without criteria or at the inappropriate time can result in many complications, it is required that patients be weaned off the ventilator as soon as possible. This study was conducted to investigate a few standard tools that predict successful and timely weaning of patients from the ventilator. In the literature, SOFA and APACHE II scores, along with various tools, including Burn, Morganroth, and Corgian, have been used in weaning patients from the ventilator. In most of these studies, the increase or decrease in the APACHE II score was correlated with the patient’s weaning time, and this score could be used as a criterion for weaning. Several authors have expressed their belief that the SOFA score in the ICU is a good indicator of the prognosis of patient’s weaning from the ventilator, length of stay, mortality, and rate of recovery. Several studies have compared SOFA and APACHE II scores and have shown that there is a positive correlation between the SOFA and APACHE II scores and that both mortality and dependence on the ventilator are related to these two scores. Another tool is Burn’s weaning program. A higher Burn score indicates successful weaning off of the ventilator, successful extubation, lower length of mechanical ventilation, and shorter stay in the hospital. However, the capabilities of the Morganroth scale and the Gluck and Corgian scoring systems were evaluated only for successful weaning off of the ventilator, and a decrease in the Morganroth and Gluck scores indicated successful weaning. PMID:27054004

  8. An Overview of the Predictor Standard Tools for Patient Weaning from Mechanical Ventilation.

    PubMed

    Dehghani, Acieh; Abdeyazdan, Gholamhossein; Davaridolatabadi, Elham

    2016-02-01

    Most patients staying in the intensive care unit (ICU) require respiratory support through a ventilator. Since prolonged mechanical ventilation and weaning from the ventilator without criteria or at the inappropriate time can result in many complications, it is required that patients be weaned off the ventilator as soon as possible. This study was conducted to investigate a few standard tools that predict successful and timely weaning of patients from the ventilator. In the literature, SOFA and APACHE II scores, along with various tools, including Burn, Morganroth, and Corgian, have been used in weaning patients from the ventilator. In most of these studies, the increase or decrease in the APACHE II score was correlated with the patient's weaning time, and this score could be used as a criterion for weaning. Several authors have expressed their belief that the SOFA score in the ICU is a good indicator of the prognosis of patient's weaning from the ventilator, length of stay, mortality, and rate of recovery. Several studies have compared SOFA and APACHE II scores and have shown that there is a positive correlation between the SOFA and APACHE II scores and that both mortality and dependence on the ventilator are related to these two scores. Another tool is Burn's weaning program. A higher Burn score indicates successful weaning off of the ventilator, successful extubation, lower length of mechanical ventilation, and shorter stay in the hospital. However, the capabilities of the Morganroth scale and the Gluck and Corgian scoring systems were evaluated only for successful weaning off of the ventilator, and a decrease in the Morganroth and Gluck scores indicated successful weaning. PMID:27054004

  9. Peanut allergens: an overview.

    PubMed

    Sáiz, Jorge; Montealegre, Cristina; Marina, Maria Luisa; García-Ruiz, Carmen

    2013-01-01

    Peanut is recognized as a potent food allergen producing one of the most frequent food allergies. This fact has originated the publication of an elevated number of scientific reports dealing with peanut allergens and, especially, the prevalence of peanut allergy. For this reason, the information available on peanut allergens is increasing and the debate about peanut allergy is always renewed. This article reviews the information currently available on peanut allergens and on the techniques used for their chemical characterization. Moreover, a general overview on the current biotechnological approaches used to reduce or eliminate peanut allergens is also provided. PMID:23638932

  10. Reactions of oxidatively activated arylamines with thiols: reaction mechanisms and biologic implications. An overview.

    PubMed Central

    Eyer, P

    1994-01-01

    Aromatic amines belong to a group of compounds that exert their toxic effects usually after oxidative biotransformation, primarily in the liver. In addition, aromatic amines also undergo extrahepatic activation to yield free arylaminyl radicals. The reactive intermediates are potential promutagens and procarcinogens, and responsible for target tissue toxicity. Since thiols react with these intermediates at high rates, it is of interest to know the underlying reaction mechanisms and the toxicologic implications. Phenoxyl radicals from aminophenols and aminyl radicals from phenylenediamines quickly disproportionate to quinone imines and quinone diimines. Depending on the structure, Michael addition or reduction reactions with thiols may prevail. Products of sequential oxidation/addition reactions (e.g., S-conjugates of aminophenols) are occasionally more toxic than the parent compounds because of their higher autoxidizability and their accumulation in the kidney. Even after covalent binding of quinone imines to protein SH groups, the resulting thioethers are able to autoxidize. The quinoid thioethers can then cross-link the protein by addition to neighboring nucleophiles. The reactions of nitrosoarenes with thiols yield a so-called "semimercaptal" from which various branching reactions detach, depending on substituents. Compounds with strong pi-donors, like 4-nitrosophenetol, give a resonance-stabilized N-(thiol-S-yl)-arylamine cation that may lead to bicyclic products, thioethers, and DNA adducts. Examples of toxicologic implications of the interactions of nitroso compounds with thiols are given for nitrosoimidazoles, heterocyclic nitroso compounds from protein pyrolysates, and nitrosoarenes. These data indicate that interactions of activated arylamines with thiols may not be regarded exclusively as detoxication reactions. PMID:7889834

  11. Toward understanding the complex mechanisms behind breast thermography: an overview for comprehensive numerical study

    NASA Astrophysics Data System (ADS)

    Jiang, Li; Zhan, Wang; Loew, Murray H.

    2011-03-01

    The abnormal thermogram has been shown to be a reliable indicator of a high risk of breast cancer. Nevertheless, a major weakness of current infrared breast thermography is its poor sensitivity for deeper tumors. Numerical modeling for breast thermography provides an effective tool to investigate the complex relationships between the breast thermal behaviors and the underlying patho-physiological conditions. We have developed a set of new modeling techniques to take into account some subtle factors usually ignored in previous studies, such as gravity-induced elastic deformations of the breast, nonlinear elasticity of soft tissues, and dynamic behavior of thermograms. Conventional "forward problem" modeling cannot be used directly to improve tumor detectability, however, because the underlying tissue thermal properties are generally unknown. Therefore, we propose an "inverse problem" modeling technique that aims to estimate the tissue thermal properties from the breast surface thermogram. Our data suggest that the estimation of the tumor-induced thermal contrast can be improved significantly by using the proposed inverse problem solving techniques to provide the individual-specific thermal background, especially for deeper tumors. We expect the proposed new methods, taken together, to provide a stronger foundation for, and greater specificity and precision in, thermographic diagnosis, and treatment, of breast cancer.

  12. Inflammatory Bowel Disease: An Overview of Immune Mechanisms and Biological Treatments

    PubMed Central

    de Mattos, Bruno Rafael Ramos; Garcia, Maellin Pereira Gracindo; Nogueira, Julia Bier; Paiatto, Lisiery Negrini; Albuquerque, Cassia Galdino; Souza, Caique Lopes; Fernandes, Luís Gustavo Romani; Tamashiro, Wirla Maria da Silva Cunha; Simioni, Patricia Ucelli

    2015-01-01

    Inflammatory bowel diseases (IBD) are characterized by chronic inflammation of the intestinal tract associated with an imbalance of the intestinal microbiota. Crohn's disease (CD) and ulcerative colitis (UC) are the most widely known types of IBD and have been the focus of attention due to their increasing incidence. Recent studies have pointed out genes associated with IBD susceptibility that, together with environment factors, may contribute to the outcome of the disease. In ulcerative colitis, there are several therapies available, depending on the stage of the disease. Aminosalicylates, corticosteroids, and cyclosporine are used to treat mild, moderate, and severe disease, respectively. In Crohn's disease, drug choices are dependent on both location and behavior of the disease. Nowadays, advances in treatments for IBD have included biological therapies, based mainly on monoclonal antibodies or fusion proteins, such as anti-TNF drugs. Notwithstanding the high cost involved, these biological therapies show a high index of remission, enabling a significant reduction in cases of surgery and hospitalization. Furthermore, migration inhibitors and new cytokine blockers are also a promising alternative for treating patients with IBD. In this review, an analysis of literature data on biological treatments for IBD is approached, with the main focus on therapies based on emerging recombinant biomolecules. PMID:26339135

  13. Computational Aeroacoustics: An Overview

    NASA Technical Reports Server (NTRS)

    Tam, Christopher K. W.

    2003-01-01

    An overview of recent advances in computational aeroacoustics (CAA) is presented. CAA algorithms must not be dispersive and dissipative. It should propagate waves supported by the Euler equations with the correct group velocities. Computation domains are inevitably finite in size. To avoid the reflection of acoustic and other outgoing waves at the boundaries of the computation domain, it is required that special boundary conditions be imposed at the boundary region. These boundary conditions either absorb all the outgoing waves without reflection or allow the waves to exit smoothly. High-order schemes, invariably, supports spurious short waves. These spurious waves tend to pollute the numerical solution. They must be selectively damped or filtered out. All these issues and relevant computation methods are briefly reviewed. Jet screech tones are known to have caused structural fatigue in military combat aircrafts. Numerical simulation of the jet screech phenomenon is presented as an example of a successful application of CAA.

  14. Digital radiography: an overview.

    PubMed

    Parks, Edwin T; Williamson, Gail F

    2002-11-15

    Since the discovery of X-rays in 1895, film has been the primary medium for capturing, displaying, and storing radiographic images. It is a technology that dental practitioners are the most familiar and comfortable with in terms of technique and interpretation. Digital radiography is the latest advancement in dental imaging and is slowly being adopted by the dental profession. Digital imaging incorporates computer technology in the capture, display, enhancement, and storage of direct radiographic images. Digital imaging offers some distinct advantages over film, but like any emerging technology, it presents new and different challenges for the practitioner to overcome. This article presents an overview of digital imaging including basic terminology and comparisons with film-based imaging. The principles of direct and indirect digital imaging modalities, intraoral and extraoral applications, image processing, and diagnostic efficacy will be discussed. In addition, the article will provide a list of questions dentists should consider prior to purchasing digital imaging systems for their practice. PMID:12444400

  15. An Overview of Filicide

    PubMed Central

    2007-01-01

    Filicide, or the murder of one's own child, is an unfathomable crime. With Andrea Yates's return to trial in the summer of 2006, filicide once again came to the forefront of psychiatric issues in the media. One positive outcome that may be derived from this tragedy is practitioners' heightened awareness that parents may, for a variety of reasons, be compelled to kill their children. This article aims to educate mental health providers about the concept of filicide by presenting a broad overview of the topic, including a discussion of its history, definitions, classifications, outcomes, and the research surrounding it. This knowledge will hopefully bring about clinicians' increased exploration of patients' thoughts of harming their children, which may ultimately lead to the prevention of these senseless crimes. PMID:20805899

  16. An overview of degradable polymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many degradable polymers are being investigated for research purpose or for possible commercial use. This overview provides a listing of the more important degradable polymers and their mechanisms of action. Some application areas, particularly in packaging, housewares, personal care, biomaterials, ...

  17. An overview of degradable polymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many degradable polymers are being investigated for research purpose or for possible commercial use. This overview provides a listing of the more important degradable polymers and their mechanisms of action. Some application areas, particularly in packaging, housewares, personal care, biomaterials...

  18. Overview of Glenn Mechanical Components Branch Research

    NASA Astrophysics Data System (ADS)

    Zakrajsek, James

    2002-09-01

    Mr. James Zakrajsek, chief of the Mechanical Components Branch, gave an overview of research conducted by the branch. Branch members perform basic research on mechanical components and systems, including gears and bearings, turbine seals, structural and thermal barrier seals, and space mechanisms. The research is focused on propulsion systems for present and advanced aerospace vehicles. For rotorcraft and conventional aircraft, we conduct research to develop technology needed to enable the design of low noise, ultra safe geared drive systems. We develop and validate analytical models for gear crack propagation, gear dynamics and noise, gear diagnostics, bearing dynamics, and thermal analyses of gear systems using experimental data from various component test rigs. In seal research we develop and test advanced turbine seal concepts to increase efficiency and durability of turbine engines. We perform experimental and analytical research to develop advanced thermal barrier seals and structural seals for current and next generation space vehicles. Our space mechanisms research involves fundamental investigation of lubricants, materials, components and mechanisms for deep space and planetary environments.

  19. Overview of Glenn Mechanical Components Branch Research

    NASA Technical Reports Server (NTRS)

    Zakrajsek, James

    2002-01-01

    Mr. James Zakrajsek, chief of the Mechanical Components Branch, gave an overview of research conducted by the branch. Branch members perform basic research on mechanical components and systems, including gears and bearings, turbine seals, structural and thermal barrier seals, and space mechanisms. The research is focused on propulsion systems for present and advanced aerospace vehicles. For rotorcraft and conventional aircraft, we conduct research to develop technology needed to enable the design of low noise, ultra safe geared drive systems. We develop and validate analytical models for gear crack propagation, gear dynamics and noise, gear diagnostics, bearing dynamics, and thermal analyses of gear systems using experimental data from various component test rigs. In seal research we develop and test advanced turbine seal concepts to increase efficiency and durability of turbine engines. We perform experimental and analytical research to develop advanced thermal barrier seals and structural seals for current and next generation space vehicles. Our space mechanisms research involves fundamental investigation of lubricants, materials, components and mechanisms for deep space and planetary environments.

  20. An Overview of Kinematic and Calibration Models Using Internal/External Sensors or Constraints to Improve the Behavior of Spatial Parallel Mechanisms

    PubMed Central

    Majarena, Ana C.; Santolaria, Jorge; Samper, David; Aguilar, Juan J.

    2010-01-01

    This paper presents an overview of the literature on kinematic and calibration models of parallel mechanisms, the influence of sensors in the mechanism accuracy and parallel mechanisms used as sensors. The most relevant classifications to obtain and solve kinematic models and to identify geometric and non-geometric parameters in the calibration of parallel robots are discussed, examining the advantages and disadvantages of each method, presenting new trends and identifying unsolved problems. This overview tries to answer and show the solutions developed by the most up-to-date research to some of the most frequent questions that appear in the modelling of a parallel mechanism, such as how to measure, the number of sensors and necessary configurations, the type and influence of errors or the number of necessary parameters. PMID:22163469

  1. An overview of Trilinos.

    SciTech Connect

    Long, Kevin R.; Tuminaro, Raymond Stephen; Bartlett, Roscoe Ainsworth; Hoekstra, Robert John; Phipps, Eric Todd; Kolda, Tamara Gibson; Lehoucq, Richard B.; Thornquist, Heidi K.; Hu, Jonathan Joseph; Williams, Alan B.; Salinger, Andrew Gerhard; Howle, Victoria E.; Pawlowski, Roger Patrick; Willenbring, James M.; Heroux, Michael Allen

    2003-08-01

    The Trilinos Project is an effort to facilitate the design, development, integration and ongoing support of mathematical software libraries. In particular, our goal is to develop parallel solver algorithms and libraries within an object-oriented software framework for the solution of large-scale, complex multi-physics engineering and scientific applications. Our emphasis is on developing robust, scalable algorithms in a software framework, using abstract interfaces for flexible interoperability of components while providing a full-featured set of concrete classes that implement all abstract interfaces. Trilinos uses a two-level software structure designed around collections of packages. A Trilinos package is an integral unit usually developed by a small team of experts in a particular algorithms area such as algebraic preconditioners, nonlinear solvers, etc. Packages exist underneath the Trilinos top level, which provides a common look-and-feel, including configuration, documentation, licensing, and bug-tracking. Trilinos packages are primarily written in C++, but provide some C and Fortran user interface support. We provide an open architecture that allows easy integration with other solver packages and we deliver our software to the outside community via the Gnu Lesser General Public License (LGPL). This report provides an overview of Trilinos, discussing the objectives, history, current development and future plans of the project.

  2. School Phobia: An Overview

    ERIC Educational Resources Information Center

    McDonald, James E.; Sheperd, George

    1976-01-01

    This article discusses general features of school phobia and specific clinical and familial traits and characteristics. Included are overviews of theoretical explanations, types of school phobia, suggested methods of treatment, and their efficacy. (Author)

  3. Planetary Seismometers: An Overview

    NASA Astrophysics Data System (ADS)

    Knapmeyer, M.; Akito, A.; Bampasidis, G.; Banerdt, W. B.; Coustenis, A.; Fouch, M. J.; Garnero, E. J.; Khavroshkin, O.; Kobayashi, N.; Moussas, X.; Pike, W. T.; Seidensticker, K. J.; Solomonidou, A.; Yu, H.; Zakharov, A.

    2012-04-01

    Seismometers were part of lander payloads since the launch of Ranger 3 in early 1962, which was the first attempt to deliver scientific instruments to the surface of another celestial body. Since then, active and passive seismic experiments were conducted with great success on the Moon, and to a lesser extent on Mars and Venus. Proposals have been made or are in preparation for new experiments with single instruments or instrument networks on Venus, Moon, Mars, Phobos, Titan, Europa, and other bodies. One instrument (CASSE, sensitive for acoustic frequencies >= 30Hz) is currently flying to comet 67P/Churyumov-Gerasimenko on board of the Rosetta Mission. We give an overview of seismometers for use in planetary missions, including instruments of past and future missions. The focus is on the current developments as represented by the authors of the presentation. These encompass a Micro-Electromechanic System, several piezoelectric transducers that are able to resist strong decelerations, as well as new developments based on laser-interferometric sensing or hydrodynamic flow of electrolytic liquids.

  4. Turbulence compensation: an overview

    NASA Astrophysics Data System (ADS)

    van Eekeren, Adam W. M.; Schutte, Klamer; Dijk, Judith; Schwering, Piet B. W.; van Iersel, Miranda; Doelman, Niek J.

    2012-06-01

    In general, long range visual detection, recognition and identification are hampered by turbulence caused by atmospheric conditions. Much research has been devoted to the field of turbulence compensation. One of the main advantages of turbulence compensation is that it enables visual identification over larger distances. In many (military) scenarios this is of crucial importance. In this paper we give an overview of several software and hardware approaches to compensate for the visual artifacts caused by turbulence. These approaches are very diverse and range from the use of dedicated hardware, such as adaptive optics, to the use of software methods, such as deconvolution and lucky imaging. For each approach the pros and cons are given and it is indicated for which scenario this approach is useful. In more detail we describe the turbulence compensation methods TNO has developed in the last years and place them in the context of the different turbulence compensation approaches and TNO's turbulence compensation roadmap. Furthermore we look forward and indicate the upcoming challenges in the field of turbulence compensation.

  5. An overview of MEDM.

    SciTech Connect

    Evans, K., Jr.

    1999-10-05

    MEDM, which is derived from Motif Editor and Display Manager, is the primary graphical user interface to the EPICS control system and has also been used for other control systems. MEDM has two modes of operation, EDIT and EXECUTE. In its EDIT mode it provides the drawing tools needed to design control screens for operator interfaces. In its EXECUTE mode it manages those screens to communicate with the control system. MEDM provides a set of interface objects that falls into three main categories: (1) Monitors, such as text, meters, and plots; (2) Controllers, such as buttons, menus, and sliders; and (3) Drawing Objects, such as lines, rectangles, and images. Each of these objects has many options, allowing for the development of screens ranging from simple to quite sophisticated. MEDM has been developed over the last decade, primarily at Argonne National Laboratory, and is a large, well tested, extensively used program. It runs on most flavors of UNIX, VMS, and Windows 95/98/NT. It has been used to design thousands of control screens, such as the one shown in Fig. 1, at the Advanced Photon Source and other sites around the world. This paper presents an overview of MEDM and its features.

  6. Trichloroethylene. I. An overview.

    PubMed

    Waters, E M; Gerstner, H B; Huff, J E

    1977-01-01

    Trichloroethylene (TCE) has been an industrial chemical of some importance for the past 50 years. First synthesized by Fischer in 1864, TCE has enjoyed considerable industrial usage as a degreaser and limited medical use as an inhalation anesthetic and analgesic. This TCE overview provides a narrative survey of the reference literature. Highlights include history, nomenclature, physical and chemical properties, manufacture, analysis, uses, metabolism, toxicology, carcinogenic potential, exposure routes, recommended standards, and conclusions. Chemically, TCE is a colorless, highly volatile liquid of molecular formula C2HCl3. Autoxidation of the unstable compound yields acidic products. Stabilizers are added to retard decomposition. TCE's multitude of industrial uses center around its highly effective fat-solvent properties. Metabolically, TCE is transformed in the liver to trichloroacetic acid, trichloroethanol, and trichloroethanol glucuronide; these breakdown products are excreted through the kidneys. Most toxic responses occur as a result of industrial exposures. TCE affects principally the central nervous system (CNS). Short exposures result in subjective symptoms such as headache, nausea, and incoordination. Longer exposures may result in CNS depression, hepatorenal failure, and increased cardiac output. Cases of sudden death following TCE exposure are generally attributed to ventricular fibrillation. Current interest in TCE has focused on recent experimental data that implicate TCE as a cause of hepatocellular carcinoma in mice. No epidemiological data are available that demonstrate a similar action in humans. The overall population may be exposed to TCE through household cleaning fluids, decaffeinated coffee, and some spice extracts. The NIOSH recommended standard for TCE is 100 ppm as a time-weighted average for an 8-hr day, with a maximum allowable peak concentration of 150 ppm for 10 min. PMID:403297

  7. Lead poisoning: An overview

    NASA Technical Reports Server (NTRS)

    Gendel, Neil

    1993-01-01

    A problem that should be of great concern to all of us is the lead poisoning of children. First, I would like to present a short overview concerning the reasons everyone should care about lead poisoning, then discuss the history of lead poisoning, what is happening today across the country, and the future.

  8. Virtual Reality: An Overview.

    ERIC Educational Resources Information Center

    Franchi, Jorge

    1994-01-01

    Highlights of this overview of virtual reality include optics; interface devices; virtual worlds; potential applications, including medicine and archaeology; problems, including costs; current research and development; future possibilities; and a listing of vendors and suppliers of virtual reality products. (Contains 11 references.) (LRW)

  9. Chiral Drugs: An Overview

    PubMed Central

    Nguyen, Lien Ai; He, Hua; Pham-Huy, Chuong

    2006-01-01

    About more than half of the drugs currently in use are chiral compounds and near 90% of the last ones are marketed as racemates consisting of an equimolar mixture of two enantiomers. Although they have the same chemical structure, most isomers of chiral drugs exhibit marked differences in biological activities such as pharmacology, toxicology, pharmacokinetics, metabolism etc. Some mechanisms of these properties are also explained. Therefore, it is important to promote the chiral separation and analysis of racemic drugs in pharmaceutical industry as well as in clinic in order to eliminate the unwanted isomer from the preparation and to find an optimal treatment and a right therapeutic control for the patient. In this article, we review the nomenclature, pharmacology, toxicology, pharmacokinetics, metabolism etc of some usual chiral drugs as well as their mechanisms. Different techniques used for the chiral separation in pharmaceutical industry as well as in clinical analyses are also examined. PMID:23674971

  10. Research reactors - an overview

    SciTech Connect

    West, C.D.

    1997-03-01

    A broad overview of different types of research and type reactors is provided in this paper. Reactor designs and operating conditions are briefly described for four reactors. The reactor types described include swimming pool reactors, the High Flux Isotope Reactor, the Mark I TRIGA reactor, and the Advanced Neutron Source reactor. Emphasis in the descriptions is placed on safety-related features of the reactors. 7 refs., 7 figs., 2 tabs.

  11. Coronary Microvascular Disease in Chronic Chagas Cardiomyopathy Including an Overview on History, Pathology, and Other Proposed Pathogenic Mechanisms

    PubMed Central

    Rossi, Marcos A.; Tanowitz, Herbert B.; Malvestio, Lygia M.; Celes, Mara R.; Campos, Erica C.; Blefari, Valdecir; Prado, Cibele M.

    2010-01-01

    This review focuses on the short and bewildered history of Brazilian scientist Carlos Chagas's discovery and subsequent developments, the anatomopathological features of chronic Chagas cardiomyopathy (CCC), an overview on the controversies surrounding theories concerning its pathogenesis, and studies that support the microvascular hypothesis to further explain the pathological features and clinical course of CCC. It is our belief that knowledge of this particular and remarkable cardiomyopathy will shed light not only on the microvascular involvement of its pathogenesis, but also on the pathogenetic processes of other cardiomyopathies, which will hopefully provide a better understanding of the various changes that may lead to an end-stage heart disease with similar features. This review is written to celebrate the 100th anniversary of the discovery of Chagas disease. PMID:20824217

  12. Mobile radio - An overview

    NASA Astrophysics Data System (ADS)

    Kucar, Andy D.

    1991-11-01

    Following a brief prologue and historical overview, such technical issues as the repertoire of systems and services, management of the airwaves, the operating environment, service quality, network issues and cell size, channel coding and modulation, speech coding, diversity, multiplex, and multiple access (FDMA, TDMA, CDMA) are discussed. Also addressed are the potential economic and sociological impacts of mobile radio communications in the wake of the redistribution of airwaves at the World Administrative Radio Conference WARC '92. Performance dependence on multipath delay (related to the cell size and terrain configuration), Doppler frequency (related to the carrier frequency, data rate, and the speed of vehicles), and message length (can dictate the choice of multiple access) is briefly discussed.

  13. SSME Curricula: An Overview

    NASA Astrophysics Data System (ADS)

    Motta, Gianmario; Barroero, Thiago; Pignatelli, Giovanni

    Services Science (SSME) is a reality. After the 2006 manifesto published by Communications of ACM several universities are launching SSME curricula. In order to give a well founded overview of SSME and related curricula, we first address SSME scope issues. Later on we summarize the main contents of the curriculum and particularly the learning approach in the core classes. As case studies, we describe the SSME curriculum of University of Peking and University of Pavia. Finally we consider results. Graduate service engineers are designers of IT-enabled services who know how to analyze and design business service chains and to identify, customize and integrate appropriate IT modules. Differently from traditional IT engineers, service engineers use a critical value based approach with a faster and comprehensive analysis

  14. Tunable lasers- an overview

    SciTech Connect

    Guenther, B.D.; Buser, R.G.

    1982-08-01

    This overview of tunable lasers describes their applicability to spectroscopy in the ultraviolet and middle infrared ranges; to rapid on-line diagnostics by ultrashort cavity lasers; to exploration, by the free electron laser, for its wide tuning in the far infrared to submillimeter region; to remote detection, in areas such as portable pollution monitors, on-line chemical analyzers, auto exhaust analyzers, and production line controls; to photochemistry; and to other potential areas in diagnostics, communications, and medical and biological sciences. The following lasers are characterized by their tunability: solid state lasers, primarily alexandrite, with a tuning range of ca 1000 Angstroms; color center lasers; semiconductor lasers; dye lasers; gas lasers, where high-pressure CO/sub 2/ discharges are the best known example for a wide tunability range, and research is continuing in systems such as the alkali dimers; and, at wavelengths beyond 10 micrometers, the possibilities beyond Cerenkov and free electron lasers.

  15. Organic photoreceptors: an overview

    NASA Astrophysics Data System (ADS)

    Melnyk, Andrew R.; Pai, David M.

    1990-07-01

    When Chester Carison invented xerography, he employed sulfur and anthracene as photoconductors. Although the initial commercialization of his idea relied on inorganic photoconductors, the current trend is towards use of organic photoconductors because of their material variety, economy and flexibility. High speed copying and printing machines use belts coated with organic photoreceptors, while personal copiers and printers use aluminum drums dip-coated with organic photoreceptors. Multilayered, organic photoreceptors are now routinely mass produced by the millions with both visible sensitivity for copiers and infrared sensitivity for printers. This paper presents a brief overview of key photoreceptor properties and follow with a survey of electronic organic materials of current interest. The photodischarge characteristic is determined mainly by three factors: the photogeneration, the injection, and the transport of charge carriers. These functions can be accomplished by separate electronic material layers; photogeneration by organic pigments and charge transport by aromatic-amine electron-donor molecules. The photogeneration layers are usually fabricated by solvent coating a dispersion of a pigment in a polymeric binder while the charge transport layers are solvent coated to form a solid solution of the aromatic amine in a polymeric binder. Examples and characteristics of organic pigments and charge transport molecules of current interest are discussed.

  16. Antiaging therapy: an overview.

    PubMed

    Vojta, C L; Fraga, P D; Forciea, M A; Lavizzo-Mourey, R

    2001-06-15

    Today's researchers are exploring caloric restriction, cell-based therapies, hormonal therapies, and genetic manipulations. So far, caloric restriction has the soundest basis, and estrogen replacement is among the interventions most widely used. As the human genome is studied, treatments with genetic mechanisms move all the closer to becoming reality. PMID:11419535

  17. Compound allergy. An overview.

    PubMed

    Bashir, S J; Maibach, H I

    1997-04-01

    This review defines the term "compound allergy" in the context of new findings, and discusses evidence that allergenic reaction products have been identified. Material was gathered by searching Index Medicus and the Science Citation Index, and reviewing several standard texts. Issues regarding the validity of patch test results are addressed and we introduce the term "pseudocompound allergy" to cover cases of false-negative patch tests. We present new theories regarding the mechanisms by which new allergens are formed and a means of classification. PMID:9165199

  18. Ankylosing spondylitis: an overview

    PubMed Central

    Sieper, J; Braun, J; Rudwaleit, M; Boonen, A; Zink, A

    2002-01-01

    Ankylosing spondylitis (AS) is a complex, potentially debilitating disease that is insidious in onset, progressing to radiological sacroiliitis over several years. Patients with symptomatic AS lose productivity owing to work disability and unemployment, have a substantial use of healthcare resources, and reduced quality of life. The pathogenesis of AS is poorly understood. However, immune mediated mechanisms involving human leucocyte antigen (HLA)-B27, inflammatory cellular infiltrates, cytokines (for example, tumour necrosis factor α and interleukin 10), and genetic and environmental factors are thought to have key roles. The detection of sacroiliitis by radiography, magnetic resonance imaging, or computed tomography in the presence of clinical manifestations is diagnostic for AS, although the presence of inflammatory back pain plus at least two other typical features of spondyloarthropathy (for example, enthesitis and uveitis) is highly predictive of early AS. Non-steroidal anti-inflammatory drugs (NSAIDs) effectively relieve inflammatory symptoms and are presently first line drug treatment. However, NSAID treatment has only a symptomatic effect and probably does not alter the disease course. For symptoms refractory to NSAIDs, second line treatments, including corticosteroids and various disease modifying antirheumatic drugs, are employed but are of limited benefit. Emerging biological therapies target the inflammatory processes underlying AS, and thus, may favourably alter the disease process, in addition to providing symptom relief. PMID:12381506

  19. Stuttering: an overview.

    PubMed

    Prasse, Jane E; Kikano, George E

    2008-05-01

    Speech dysfluency (stuttering) is common in children. Although stuttering often resolves before adulthood, it can cause significant anxiety for children and their families. Stuttering speech patterns are often easily identifiable; when a child is learning to talk, repetition of sounds or words, prolonged pauses, or excessively long sounds in words usually occur. Secondary behaviors (e.g., eye blinking, jaw jerking, involuntary head or other movements) that accompany stuttering can further embarrass the child, leading to a fear of speaking. The etiology of stuttering is controversial, but contributing factors may include cognitive abilities, genetics, sex of the child, and environmental influences. Research has shown that more than 80 percent of stuttering cases are classified as developmental problems, although stuttering can also be classified as a neurologic or, less commonly, psychogenic problem. The initial assessment of patients who stutter addresses the severity of dysfluency; secondary behaviors; and the impact of stuttering, such as patient distress. Further testing is useful in assessing the need for therapy. Pharmacologic therapy has not been shown to improve stuttering. Encouraging patients to talk slowly and the use of fluency-shaping mechanisms such as delayed auditory feedback devices to slow the speech rate can help minimize or eliminate stuttering. For patients with persistent stuttering, controlled fluency or stuttering modification therapy may be effective. PMID:18540491

  20. Food Allergy: An Overview

    MedlinePlus

    ... A version of the guidelines for the general public is also available on the NIAID Web site. 25 NIAID I FOOD ALLERGY Glossary allergen —a substance that causes an allergic reaction. allergenic —describes a substance that produces an allergic ...

  1. Thermionic reactor program - An overview.

    NASA Technical Reports Server (NTRS)

    Beard, D. S.; Lynch, J. J.

    1972-01-01

    An overview of the AEC/NASA thermionic reactor program is presented with emphasis on the latest progress in this technology. The possible applications for utilization of thermionic reactors are reviewed and the joint AEC/NASA program approach to demonstrate thermionic technology is outlined. The thermionic reactor technology programs of France, West Germany, and the Soviet Union are highlighted.

  2. An overview of computer vision

    NASA Technical Reports Server (NTRS)

    Gevarter, W. B.

    1982-01-01

    An overview of computer vision is provided. Image understanding and scene analysis are emphasized, and pertinent aspects of pattern recognition are treated. The basic approach to computer vision systems, the techniques utilized, applications, the current existing systems and state-of-the-art issues and research requirements, who is doing it and who is funding it, and future trends and expectations are reviewed.

  3. Hair cosmetics: an overview.

    PubMed

    Gavazzoni Dias, Maria Fernanda Reis

    2015-01-01

    Hair cosmetics are an important tool that helps to increase patient's adhesion to alopecia and scalp treatments. This article reviews the formulations and the mode of action of hair cosmetics: Shampoos, conditioners, hair straightening products, hair dyes and henna; regarding their prescription and safetiness. The dermatologist's knowledge of hair care products, their use, and their possible side effects can extend to an understanding of cosmetic resources and help dermatologists to better treat hair and scalp conditions according to the diversity of hair types and ethnicity. PMID:25878443

  4. Hair Cosmetics: An Overview

    PubMed Central

    Gavazzoni Dias, Maria Fernanda Reis

    2015-01-01

    Hair cosmetics are an important tool that helps to increase patient's adhesion to alopecia and scalp treatments. This article reviews the formulations and the mode of action of hair cosmetics: Shampoos, conditioners, hair straightening products, hair dyes and henna; regarding their prescription and safetiness. The dermatologist's knowledge of hair care products, their use, and their possible side effects can extend to an understanding of cosmetic resources and help dermatologists to better treat hair and scalp conditions according to the diversity of hair types and ethnicity. PMID:25878443

  5. Global Education: An Overview.

    ERIC Educational Resources Information Center

    Becker, James M.

    1988-01-01

    Discusses the different definitions and conceptualizations of global education, stating that much of the traditional curriculum of international studies can be reinterpreted to prepare students to participate in an interdependent society. Gives nine objectives for global education, and delineates the issues surrounding current conceptions of…

  6. Productivity: An Overview.

    ERIC Educational Resources Information Center

    Swartz, Carl

    This training package explains productivity in terms of the difference between worker output and company input. Output is defined in terms of the products and/or services of an organization (number and/or quality of units produced, efficiency of time use, marginal profits) and in terms of behavior (labor turnover, disruptions in routine, wasted…

  7. An Overview of SAL

    NASA Technical Reports Server (NTRS)

    Bensalem, Saddek; Ganesh, Vijay; Lakhnech, Yassine; Munoz, Cesar; Owre, Sam; Ruess, Harald; Rushby, John; Rusu, Vlad; Saiedi, Hassen; Shankar, N.

    2000-01-01

    To become practical for assurance, automated formal methods must be made more scalable, automatic, and cost-effective. Such an increase in scope, scale, automation, and utility can be derived from an emphasis on a systematic separation of concerns during verification. SAL (Symbolic Analysis Laboratory) attempts to address these issues. It is a framework for combining different tools to calculate properties of concurrent systems. The heart of SAL is a language, developed in collaboration with Stanford, Berkeley, and Verimag for specifying concurrent systems in a compositional way. Our instantiation of the SAL framework augments PVS with tools for abstraction, invariant generation, program analysis (such as slicing), theorem proving, and model checking to separate concerns as well as calculate properties (i.e., perform, symbolic analysis) of concurrent systems. We. describe the motivation, the language, the tools, their integration in SAL/PAS, and some preliminary experience of their use.

  8. Conservative mastectomies: an overview

    PubMed Central

    Nava, Maurizio Bruno; Catanuto, Giuseppe

    2015-01-01

    Conservative mastectomies provide removal of the entire breast parenchyma, saving the outer covering of the mammary gland with the possibility of performing an immediate reconstruction preserving women body image. We rationalised and systematically organized our reconstructive algorythms giving a new different light to mastectomies, the so-called “conservative mastectomies”, an oxymoron indicating skin-sparing mastectomies (SSM), nipple-areola complex-sparing mastectomies (NSM) and skin-reducing mastectomies (SRM). Eventhough randomized controlled trials comparing conservative mastectomies with traditional mastectomy and breast conserving surgery would be auspicable in order to achieve higher levels of evidence, we could confidently conclude that conservative mastectomies offer the psychological advantages of good cosmesis and maintenance of woman body image without compromising the oncological safety of mastectomy. PMID:26645000

  9. Plantar Hyperhidrosis: An Overview.

    PubMed

    Vlahovic, Tracey C

    2016-07-01

    Plantar hyperhidrosis, excessive sweating on the soles of feet, can have a significant impact on patients' quality of life and emotional well-being. Hyperhidrosis is divided into primary and secondary categories, depending on the cause of the sweating, with plantar hyperhidrosis typically being primary and idiopathic. There is an overall increased risk of cutaneous infection in the presence of hyperhidrosis, including fungal, bacterial, and viral infections. This article discusses a range of treatment options including topical aluminum chloride, iontophoresis, injectable botulinum toxin A, glycopyrrolate, oxybutynin, laser, and endoscopic lumbar sympathectomy. Lifestyle changes regarding hygiene, shoe gear, insoles, and socks are also discussed. PMID:27215162

  10. Cold electronics: An overview

    NASA Technical Reports Server (NTRS)

    Kirschman, R.

    1984-01-01

    Generally speaking, several roles are seen for low temperatures in electronics: As a means of extracting better performance from existing technology, avoiding expense and delay required for the advances in design or fabrication which would be needed to achieve the same performance at room temperature. As a necessity in the quest for improved performance, to counteract detrimental effects which arises as technology is pushed to extremes. As an opportunity to take advantage of effects made available by low temperature operation, and to develop new devices based on them. The electronic devices and circuits considered are those based on semiconductivity. Superconductive devices and circuits are not included.

  11. An overview of diabetes.

    PubMed

    Mayo, Paula

    2016-07-13

    Healthcare professionals in all settings increasingly encounter people with diabetes. Suboptimal control of diabetes may have harmful effects on multiple systems in the body and can result in life-changing and life-threatening complications. Therefore, it is crucial that all healthcare professionals have an understanding of diabetes. This article considers the increase in people developing diabetes worldwide. It defines type 1 and type 2 diabetes and discusses the associated pathophysiology and predisposing factors. The article outlines the basis for the development of the typical signs and symptoms associated with high blood glucose levels. Current guidelines for diagnosing a person with diabetes are considered. PMID:27406520

  12. Onchomycosis: an overview.

    PubMed

    Elewski, Boni E; Rich, Phoebe; Tosti, Antonella; Pariser, David M; Scher, Richard; Daniel, Ralph C; Gupta, Aditya K

    2013-07-01

    Onychomycosis is a fungal infection of the nail unit, more common in toenails than in fingernails, and caused by a variety of fungi including dermatophytes, nondermatophyte molds, and Candida. There are 4 to 5 subtypes related to the method of fungal invasion of the nail unit, the most common being distal lateral subungual onychomycosis. Here the fungus enters the distal lateral part of the nail bed, the region of the hyponychium, often as an extension of tinea pedis. Hyperkeratosis occurs under the nail plate, resulting in detachment of the nail plate from the nail bed (onycholysis), with subungual thickening. PMID:23884508

  13. Global Biogeochemistry: an Overview

    NASA Technical Reports Server (NTRS)

    Moore, B., III

    1984-01-01

    The dynamic biogeochemical equilibria among the major pools of carbon, nitrogen, sulfur, and phosphorus represented by terrestrial biomes, the world's oceans, and the troposphere are disturbed. Since even the most rapid processes of adjustments among the reservoirs take decades, new equilibria are far from established. These human-induced perturbations and the system's subsequent responses constitute an on-going biogeochemical experiment at the global level. Current and new information must be combined in a way that allows testing of various hypotheses about the workings of global biogeochemical systems. This enables assessment of current knowledge and evaluation of the gaps.

  14. An Overview of Alopecias

    PubMed Central

    Qi, Ji; Garza, Luis A.

    2014-01-01

    Hair loss is a topic of enormous public interest and understanding the pathophysiology and treatment of various alopecias will likely make a large impact on patients’ lives. The investigation of alopecias also provides important insight in the basic sciences; for instance, the abundance of stem cell populations and regenerative cycles that characterize a hair follicle render it an excellent model for the study of stem cell biology. This review seeks to provide a concise summary of the major alopecias with regard to presentation and management, and correlate these to recent advances in relevant research on pathogenesis. PMID:24591533

  15. Lipoid pneumonia: an overview.

    PubMed

    Hadda, Vijay; Khilnani, Gopi C

    2010-12-01

    Lipoid pneumonia is an uncommon disease caused by the presence of lipid in the alveoli. It is classified into two major groups, depending on whether the lipid/oil in the respiratory tract is from an exogenous (exogenous lipoid pneumonia) or endogenous/idiopathic (endogenous lipoid pneumonia) source. The usual presentation occurs with insidious onset and nonspecific respiratory symptoms such as dyspnea and/or cough. The main radiological findings include airspace consolidations, ground-glass attenuation, airspace nodules and 'crazy-paving' pattern. However, the radiological appearance of the disorder can mimic many other lung diseases, including carcinoma. Owing to the nonspecific clinical presentation and radiological features, the diagnosis is often missed or delayed. Pathologically, lipoid pneumonia is a chronic foreign body reaction to fat, characterized by lipid-laden macrophages. Diagnosis of this disease requires a high index of suspicion and can be confirmed by demonstration of lipid-laden macrophages in respiratory samples such as sputum, bronchoalveolar lavage fluid or fine-needle aspiration cytology/biopsy from lung lesions. Treatment protocols for this illness are poorly defined. PMID:21128754

  16. Learning disabilities: an overview.

    PubMed

    Erenberg, G

    1991-03-01

    Children with learning disabilities form a large pool of patients seen by neurologists for help in understanding the disability and deciding which forms of remediation are appropriate. Learning disabilities may accompany a large variety of other neurologic disabilities, but the usual child with such a problem is in excellent health. A thorough office evaluation for possible medical problems is always necessary, but most children do not require laboratory testing. All children with learning disabilities, whether or not they have accompanying neurologic problems, should be seen for psychological and/or educational evaluation. Some children may also benefit from an evaluation by a speech and language pathologist, occupational therapist, or ophthalmologist. The neurologist, alone or in association with a child psychologist, should also investigate the possible association of learning disabilities with attention deficit hyperactivity disorder. It is only for children with this component of learning problems that the possibility of medication arises. Working closely with the family, the child's school system, and other involved professionals becomes an important aspect of providing full and necessary help to children with learning disabilities. A caring physician can be a major help to the child and his family in understanding this disorder and supporting them during a difficult time. PMID:2034911

  17. Managing change: an overview.

    PubMed

    Lorenzi, N M; Riley, R T

    2000-01-01

    As increasingly powerful informatics systems are designed, developed, and implemented, they inevitably affect larger, more heterogeneous groups of people and more organizational areas. In turn, the major challenges to system success are often more behavioral than technical. Successfully introducing such systems into complex health care organizations requires an effective blend of good technical and good organizational skills. People who have low psychological ownership in a system and who vigorously resist its implementation can bring a "technically best" system to its knees. However, effective leadership can sharply reduce the behavioral resistance to change-including to new technologies-to achieve a more rapid and productive introduction of informatics technology. This paper looks at four major areas-why information system failures occur, the core theories supporting change management, the practical applications of change management, and the change management efforts in informatics. PMID:10730594

  18. Pythium insidiosum: an overview.

    PubMed

    Gaastra, Wim; Lipman, Len J A; De Cock, Arthur W A M; Exel, Tim K; Pegge, Raymond B G; Scheurwater, Josje; Vilela, Raquel; Mendoza, Leonel

    2010-11-20

    Pythium insidiosum is an oomycete pathogenic in mammals. The infection occurs mainly in tropical and subtropical areas, particularly in horses, dogs and humans. Infection is acquired through small wounds via contact with water that contains motile zoospores or other propagules (zoospores or hyphae). The disease, though described as emerging has in fact already been described since 1884. Depending on the site of entry, infection can lead to different forms of pythiosis i.e. a cutaneous, vascular, ocular, gastrointestinal and a systemic form, which is rarely seen. The infection is not contagious; no animal-animal or animal-human transmission has been reported so far. Therapy includes radical surgery, antifungal drugs, immunotherapy or a combination of these therapies. The prevention to contract the disease in endemic areas is difficult. Avoiding stagnant waters could be of help, although the presence of P. insidiosum on grass and soil in enzootic areas renders this practice useless. PMID:20800978

  19. Loricrin – an overview

    PubMed Central

    Nithya, S; Radhika, T; Jeddy, Nadeem

    2015-01-01

    Loricrin is a terminally differentiating structural protein comprising more than 70% of the cornified envelope. It contributes to the protective barrier function of the stratum corneum. In vivo, loricrin is expressed inall mammalian stratified epithelia with the highest levels of expression in humid tissues such as newborn epidermis, the epithelia of oral and anal mucosa, esophagus, foreskin, vagina and the epidermal parts of sweat ducts. Loricrin is not expressed in non keratinizing epithelia and its expression at these sites actually represents a defensive or protective mechanismof the body. An insight into this protein- “Loricrin” can shed light to its potential as a marker in the early stages of potentially malignant disorders like oral sub mucous fibrosis and leukoplakia. This compilation has been done by taking into account the existing literature, reviews and original studies on loricrin, a major component of the cornifiedcell envelope, its structure and the alterations that result due to its absence or presence of both the epidermis and the oral mucosa. PMID:26097310

  20. Campylobacteriosis - an overview.

    PubMed

    Sarkar, S R; Hossain, M A; Paul, S K; Ray, N C; Sultana, S; Rahman, M M; Islam, A

    2014-01-01

    Campylobacteriosis is a collective term, used for infectious, emerging foodborne disease caused by Campylobacter species comprising Gram negative, curved, and microaerophilic pathogens. The true incidence of human campylobacteriosis is unknown for most countries of the world including Bangladesh. But campylobacteriosis is not uncommon in our country. Due to its increasing incidence in many countries of the world, it is an important issue now a day. Animals such as birds are the main sources of infection. Farm animals such as cattle, poultry are commonly infected from such sources and raw milk, undercooked or poorly handled meat becomes contaminated. Transmission of campylobacteriosis to human occurs through consumption of infected, unpasteurized animal milk and milk products, undercooked poultry and through contaminated drinking water. Contact with contaminated poultry, livestock or household pets, especially puppies, can also cause disease. Due to variability of clinical features and limited availability of laboratory facilities, the disease remains largely under-reported. Early and specific diagnosis is important to ensure a favourable outcome regarding this food borne disease. Antibiotic treatment is controversial, and has only a benefit on the duration of symptoms. Campylobacter infections can be prevented by some simple hygienic food handling practices. PMID:24584395

  1. Captopril--an overview.

    PubMed

    Rosendorff, C

    1982-10-16

    Captopril (Capoten; Squibb) is a specific orally active antagonist of peptidyl-dipeptide carboxyhydrolase, the enzyme which converts angiotensin I to angiotensin II and which inactivates bradykinin. Captopril therefore reduces blood pressure in a variety of animal models of hypertension. In 96 studies on 1570 patients, captopril has been shown to be superior to placebo and equivalent to either propranolol or a diuretic in the treatment of essential hypertension. In the management of severe treatment-resistant hypertension, the response to captopril (alone or in combination with a diuretic and/or propranolol) was better than the response to standard triple therapy. Captopril, with digitalis and a diuretic, also improved the haemodynamic and clinical status of patients with refractory congestive heart failure. Side-effects include skin rashes (15%), proteinuria (1,1%, or 0,4% of patients with no prior renal disease) and the nephrotic syndrome (0,9%, or 0,3% of patients with no prior renal disease). Nearly all patients with the nephrotic syndrome in whom renal biopsies were performed were found to have membranous glomerulopathy. Neutropenia (total white cell count less than 1,000/microliter) was found in 33 of over 6,000 patients (0,4%), but in all cases there were other possible causes for this. Captopril is the first of an important group of antihypertensive and afterload-reducing drugs; its major indications are likely to be in the treatment of refractory severe hypertension or congestive heart failure. PMID:6214858

  2. Anogenital Pruritus - An Overview.

    PubMed

    Swamiappan, Murugan

    2016-04-01

    Anogenital pruritus is defined as intense itching, acute or chronic, affecting the anal, perianal, perineal and genital skin, which is a dominant problem in the course of various cutaneous and systemic conditions. It is one of the common, extremely annoying symptom for which patients attend the Dermatology Outpatient Department (OPD). Anogenital skin is highly sensitive to soaps, perfumes, clothing and superficial trauma and it is more prone for itchy dermatoses as a result of warmth, friction, lack of aeration, sweating and occlusive inner garments. Anogenital pruritus is associated with a wide spectrum of diseases which includes localized infections, infestations, inflammatory dermatoses, allergic and irritant conditions, anorectal diseases, systemic causes, nutritional disorders, psychological and when the cause cannot be found out it is often termed idiopathic. Patients are highly reluctant in consulting the physician for anogenital itch in the early stage, they usually present at a later stage with either atypical manifestations or depigmentation and lichenification, secondary to constant scratching. They often resort to over the counter topical agents, particularly combination products which contain topical steroids. The irrational use of such products results in complications like skin atrophy, striae, incognito etc. A proper clinical history, clinical examination, investigations like scrapping for fungus and itch mite, skin biopsy, patch test and relevant blood investigations to rule out systemic conditions should be carried out, when needed, to arrive at an accurate diagnosis, before treating the patient. PMID:27190932

  3. An overview of the asteroids

    NASA Technical Reports Server (NTRS)

    Binzel, Richard P.

    1989-01-01

    An introductory overview of the field of asteroid science is presented, with emphasis placed on the accomplishments of the 1980s. Following the survey of known asteroids, attention is given to the observations of asteroids with the IRAS. Particular consideration is given to the origin and evolution of asteroids and their interrelations. Possible future directions of asteroid research are discussed together with the potential of the Hubble Space Telescope for providing new data on asteroid surface chemistry, geology, structure, and morphology.

  4. High Performance Fortran: An overview

    SciTech Connect

    Zosel, M.E.

    1992-12-23

    The purpose of this paper is to give an overview of the work of the High Performance Fortran Forum (HPFF). This group of industry, academic, and user representatives has been meeting to define a set of extensions for Fortran dedicated to the special problems posed by a very high performance computers, especially the new generation of parallel computers. The paper describes the HPFF effort and its goals and gives a brief description of the functionality of High Performance Fortran (HPF).

  5. Acquired Antibiotic Resistance Genes: An Overview

    PubMed Central

    van Hoek, Angela H. A. M.; Mevius, Dik; Guerra, Beatriz; Mullany, Peter; Roberts, Adam Paul; Aarts, Henk J. M.

    2011-01-01

    In this review an overview is given on antibiotic resistance (AR) mechanisms with special attentions to the AR genes described so far preceded by a short introduction on the discovery and mode of action of the different classes of antibiotics. As this review is only dealing with acquired resistance, attention is also paid to mobile genetic elements such as plasmids, transposons, and integrons, which are associated with AR genes, and involved in the dispersal of antimicrobial determinants between different bacteria. PMID:22046172

  6. Space industrialization studies - An overview

    NASA Technical Reports Server (NTRS)

    Priest, C.; Bradford, R.

    1977-01-01

    An overview of NASA's current planning for a space industrialization program is described as an introduction to the papers on Space Industrialization being presented by Rockwell International Corporation and Science Applications Incorporated. Background information is presented that outlines the integrated planning process which resulted in specific long range goals and objectives being formulated for NASA programs in technology, environment, resources, earth science, communications, space exploration, aeronautics, and an expanded application of space called space industrialization. Program objectives for NASA's Industrialization of Space and studies on potential near term supporting elements (Space Platform, Large Space Structures, Orbital Operations Capabilities Development, Space Manufacturing Module) are discussed.

  7. Multiphase inverse modeling: An Overview

    SciTech Connect

    Finsterle, S.

    1998-03-01

    Inverse modeling is a technique to derive model-related parameters from a variety of observations made on hydrogeologic systems, from small-scale laboratory experiments to field tests to long-term geothermal reservoir responses. If properly chosen, these observations contain information about the system behavior that is relevant to the performance of a geothermal field. Estimating model-related parameters and reducing their uncertainty is an important step in model development, because errors in the parameters constitute a major source of prediction errors. This paper contains an overview of inverse modeling applications using the ITOUGH2 code, demonstrating the possibilities and limitations of a formalized approach to the parameter estimation problem.

  8. Facing Tomorrow's Challenges - An Overview

    USGS Publications Warehouse

    U.S. Geological Survey

    2008-01-01

    In 2007, the U.S. Geological Survey (USGS) developed a science strategy outlining the major natural-science issues facing the Nation in the next decade. The science strategy consists of six science directions of critical importance, focusing on areas where natural science can make a substantial contribution to the well-being of the Nation and the world. This fact sheet is an overview of the science strategy and describes how USGS research can strengthen the Nation with information needed to meet the challenges of the 21st century.

  9. US PWR steam generator management: An overview

    SciTech Connect

    Welty, C.S. Jr.

    1997-02-01

    This paper provides an overview on the status of steam generator management activities in US PWRs, and includes: (1) an overview of the impact of steam generator problems; (2) a brief discussion of historical damage trends and the current damage mechanism of most concern; (3) a discussion of the elements of {open_quotes}steam generator management{close_quotes}; and (4) a description of the approach being followed to implement a degradation-specific protocol for tubing inspection and repair. This paper was prepared in conjunction with another paper presented during the Plenary Session of this Conference, {open_quotes}Steam Generator Degradation: Current Mitigation Strategies for Controlling Corrosion{close_quotes}, and is provided as a supplement to that material.

  10. An overview of butanol-induced developmental neurotoxicity and the potential mechanisms related to these observed effects.

    PubMed

    Bale, Ambuja S; Lee, Janice S

    2016-01-01

    The purpose of this article is to briefly review the published literature on the developmental neurotoxic effects, including potential mechanisms, of four butanols: n-butanol, sec-butanol, tert-butanol, isobutanol, and identify data gaps and research needs for evaluation of human health risks in this area. Exposure potential to these four butanols is considerable given the high production volume (>1 billion lb) of n- and tert-butanol and moderate production volumes (100-500 million lb) of sec- and isobutanol. With the impetus to derive cleaner gasoline blends, butanols are being considered for use as fuel oxygenates. Notable signs of neurotoxicity and developmental neurotoxicity have been observed in some studies where laboratory animals (rodents) were gestationally exposed to n- or tert-butanol. Mechanistic data relevant to the observed developmental neurotoxicity endpoints were also reviewed to hypothesize potential mechanisms associated with the developmental neurotoxicity outcome. Data from the related and highly characterized alcohol, ethanol, were included to examine consistencies between this compound and the four butanols. It is widely known that alcohols, including butanols, interact with several ion channels and modulate the function of these targets following both acute and chronic exposures. In addition, n- and sec-butanol have been demonstrated to inhibit fetal rat brain astroglial cell proliferation. Further, rat pups exposed to n-butanol in utero were also reported to have significant increases in brain levels of dopamine and serotonin, but decreases in serotonin levels were noted with gestational exposure to tert-butanol. tert-Butanol was reported to inhibit muscarinic receptor-stimulated phosphoinositide metabolism which has been hypothesized to be a possible target for the neurotoxic effects of ethanol during brain development. The mechanistic data for the butanols support developmental neurotoxicity that has been observed in some of the rodent

  11. Aviation combustion toxicology: an overview.

    PubMed

    Chaturvedi, Arvind K

    2010-01-01

    Aviation combustion toxicology is a subspecialty of the field of aerospace toxicology, which is composed of aerospace and toxicology. The term aerospace, that is, the environment extending above and beyond the surface of the Earth, is also used to represent the combined fields of aeronautics and astronautics. Aviation is another term interchangeably used with aerospace and aeronautics and is explained as the science and art of operating powered aircraft. Toxicology deals with the adverse effects of substances on living organisms. Although toxicology borrows knowledge from biology, chemistry, immunology, pathology, physiology, and public health, the most closely related field to toxicology is pharmacology. Economic toxicology, environmental toxicology, and forensic toxicology, including combustion toxicology, are the three main branches of toxicology. In this overview, a literature search for the period of 1960-2007 was performed and information related to aviation combustion toxicology collected. The overview included introduction; combustion, fire, and smoke; smoke gas toxicity; aircraft material testing; fire gases and their interactive effects; result interpretation; carboxyhemoglobin and blood cyanide ion levels; pyrolytic products of aircraft engine oils, fluids, and lubricants; and references. This review is anticipated to be an informative resource for aviation combustion toxicology and fire-related casualties. PMID:20109297

  12. An overview of job embeddedness.

    PubMed

    Reitz, O Ed; Anderson, Mary Ann

    2011-01-01

    Nursing turnover in health care organizations is a considerable problem that needs to be reframed within the context of "nurse retention" and "job embeddedness" (JE). A construct from the business literature, JE has been associated with "retention" or "antiwithdrawal." Conversely, turnover encompasses the process of quitting. This distinction is significant. JE represents a mediating construct between various "on-the-job" (organizational) factors, "off-the-job" (community) factors, and employee retention. This article presents an overview of JE including the dimensions, the related concepts of turnover and retention, and associated research. JE may be used to develop specific nurse-retention strategies following careful organizational and community assessment. With the current and looming nursing shortage, perhaps it is time for health care institutions to consider the adaptation of JE tenets. PMID:21925466

  13. An Overview of Climatic Elements

    NASA Technical Reports Server (NTRS)

    Crutcher, H. L.; Johnson, D. L.

    2007-01-01

    This Technical Publication (TP) addresses some climatic elements with emphasis on atmospheric composition, including gas radiative characteristics. Solar radiation is discussed with considerable information on the mathematical and statistical formulae. On a worldwide basis, temperature and precipitation for the globe are discussed along with interaction in drought. Also included is the simultaneous interaction with winds, humidity, and solar radiation. Volcanology gets minimum treatment. The oceans and seas are treated in chart form along with the interrelationship of oceanic currents and El Nino and La Nina, and ENSO phenomena. Upper air circulations are discussed. Various cloud formations up to 85-95 km altitude are described. Information on tornadoes and hurricanes is also included. One section is devoted to the climate physical-chemical elements. A short discussion is given on the importance for the quality of data and/or information in descriptions of the climate. This TP presents only an overview or survey of these and other various climatic elements.

  14. 12. Overview of bay with hydraulic mechanism northwest Mississippi ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Overview of bay with hydraulic mechanism northwest - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  15. 5. Overview of bay with geared mechanism to northeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Overview of bay with geared mechanism to northeast - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  16. 11. Overview of bay with hydraulic mechanism to northeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Overview of bay with hydraulic mechanism to northeast - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  17. 6. Overview of bay with geared mechanism to northwest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Overview of bay with geared mechanism to northwest - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  18. An overview of elevated temperature damage mechanisms and fatigue behavior of a unidirectional SCS-6/Ti-15-3 composite

    NASA Technical Reports Server (NTRS)

    Castelli, Michael G.; Gayda, John

    1993-01-01

    The fatigue behavior of a unidirectionally reinforced titanium matrix composite (TMC), SiC/Ti-15-3, was thoroughly characterized to support life prediction modeling of advanced TMC disks designed for gas turbine engine applications. The results of this coupon-level experimental investigation are reviewed. On a stress basis, the isothermal fatigue behavior of the (0 deg) TMC revealed significant improvements over the unreinforced matrix. In contrast, the (90 deg) TMC exhibited degraded properties and lives for similar comparisons. This was attributed to the weak fiber/matrix interfacial bond. Encasing the (0 deg) TMC with a Ti-15-3 case did not affect isothermal fatigue lives at higher strain levels. However, at lower strain levels, rapid initiation and propagation of large fatigue cracks in the case degraded the fatigue lives. Thermomechanical fatigue (TMF) lives were significantly reduced for the (0 deg) TMC when compared to isothermal lives. At high strains, in-phase TMF produced extremely short lives. This degradation was attributed to fiber overload failures brought about by stress relaxation in the matrix. At low strains, out-of-phase TMF conditions became life limiting. Environment-assisted surface cracking was found to accelerate fatigue failure. This produced extensive matrix damage with minimal fiber damage. For the (90 deg) TMC, TMF conditions did not promote an additional degradation in cyclic life beyond that observed under isothermal conditions.

  19. Mechanisms of Resistance to Aminoglycoside Antibiotics: Overview and Perspectives

    PubMed Central

    Garneau-Tsodikova, Sylvie

    2015-01-01

    Aminoglycoside (AG) antibiotics are used to treat many Gram-negative and some Gram-positive infections and, importantly, multidrug-resistant tuberculosis. Among various bacterial species, resistance to AGs arises through a variety of intrinsic and acquired mechanisms. The bacterial cell wall serves as a natural barrier for small molecules such as AGs and may be further fortified via acquired mutations. Efflux pumps work to expel AGs from bacterial cells, and modifications here too may cause further resistance to AGs. Mutations in the ribosomal target of AGs, while rare, also contribute to resistance. Of growing clinical prominence is resistance caused by ribosome methyltransferases. By far the most widespread mechanism of resistance to AGs is the inactivation of these antibiotics by AG-modifying enzymes. We provide here an overview of these mechanisms by which bacteria become resistant to AGs and discuss their prevalence and potential for clinical relevance. PMID:26877861

  20. An Overview of Biofield Devices

    PubMed Central

    Muehsam, David; Chevalier, Gaétan; Barsotti, Tiffany

    2015-01-01

    Advances in biophysics, biology, functional genomics, neuroscience, psychology, psychoneuroimmunology, and other fields suggest the existence of a subtle system of “biofield” interactions that organize biological processes from the subatomic, atomic, molecular, cellular, and organismic to the interpersonal and cosmic levels. Biofield interactions may bring about regulation of biochemical, cellular, and neurological processes through means related to electromagnetism, quantum fields, and perhaps other means of modulating biological activity and information flow. The biofield paradigm, in contrast to a reductionist, chemistry-centered viewpoint, emphasizes the informational content of biological processes; biofield interactions are thought to operate in part via low-energy or “subtle” processes such as weak, nonthermal electromagnetic fields (EMFs) or processes potentially related to consciousness and nonlocality. Biofield interactions may also operate through or be reflected in more well-understood informational processes found in electroencephalographic (EEG) and electrocardiographic (ECG) data. Recent advances have led to the development of a wide variety of therapeutic and diagnostic biofield devices, defined as physical instruments best understood from the viewpoint of a biofield paradigm. Here, we provide a broad overview of biofield devices, with emphasis on those devices for which solid, peer-reviewed evidence exists. A subset of these devices, such as those based upon EEG- and ECG-based heart rate variability, function via mechanisms that are well understood and are widely employed in clinical settings. Other device modalities, such a gas discharge visualization and biophoton emission, appear to operate through incompletely understood mechanisms and have unclear clinical significance. Device modes of operation include EMF-light, EMF-heat, EMF-nonthermal, electrical current, vibration and sound, physical and mechanical, intentionality and nonlocality

  1. An Overview of Biofield Devices.

    PubMed

    Muehsam, David; Chevalier, Gaétan; Barsotti, Tiffany; Gurfein, Blake T

    2015-11-01

    Advances in biophysics, biology, functional genomics, neuroscience, psychology, psychoneuroimmunology, and other fields suggest the existence of a subtle system of "biofield" interactions that organize biological processes from the subatomic, atomic, molecular, cellular, and organismic to the interpersonal and cosmic levels. Biofield interactions may bring about regulation of biochemical, cellular, and neurological processes through means related to electromagnetism, quantum fields, and perhaps other means of modulating biological activity and information flow. The biofield paradigm, in contrast to a reductionist, chemistry-centered viewpoint, emphasizes the informational content of biological processes; biofield interactions are thought to operate in part via low-energy or "subtle" processes such as weak, nonthermal electromagnetic fields (EMFs) or processes potentially related to consciousness and nonlocality. Biofield interactions may also operate through or be reflected in more well-understood informational processes found in electroencephalographic (EEG) and electrocardiographic (ECG) data. Recent advances have led to the development of a wide variety of therapeutic and diagnostic biofield devices, defined as physical instruments best understood from the viewpoint of a biofield paradigm. Here, we provide a broad overview of biofield devices, with emphasis on those devices for which solid, peer-reviewed evidence exists. A subset of these devices, such as those based upon EEG- and ECG-based heart rate variability, function via mechanisms that are well understood and are widely employed in clinical settings. Other device modalities, such a gas discharge visualization and biophoton emission, appear to operate through incompletely understood mechanisms and have unclear clinical significance. Device modes of operation include EMF-light, EMF-heat, EMF-nonthermal, electrical current, vibration and sound, physical and mechanical, intentionality and nonlocality, gas and

  2. An Energy Overview of Ecuador

    SciTech Connect

    anon.

    2003-10-17

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Ecuador. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  3. An Energy Overview of Croatia

    SciTech Connect

    anon.

    2003-10-17

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Croatia. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  4. An Energy Overview of Mexico

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Mexico. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  5. An Energy Overview of Colombia

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site--each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Colombia. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  6. An Energy Overview of Argentina

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Argentina. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  7. An Energy Overview of Brazil

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Brazil. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  8. An Energy Overview of Romania

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Romania. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  9. An Energy Overview of Chile

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Chile. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  10. An Energy Overview of India

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is India. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  11. An Energy Overview of Slovenia

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Slovenia. The site is designed to be dynamic. Updates to the overviews will be made as need and resource s permit.

  12. An Energy Overview of Peru

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Peru. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  13. An Energy Overview of Venezuela

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Venezuela. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit.

  14. The FETCH experiment: An overview

    NASA Astrophysics Data System (ADS)

    Hauser, D.; Branger, H.; Bouffies-Cloché, S.; Despiau, S.; Drennan, W. M.; Dupuis, H.; Durand, P.; Durrieu de Madron, X.; Estournel, C.; Eymard, L.; Flamant, C.; Graber, H. C.; GuéRin, C.; Kahma, K.; Lachaud, G.; LefèVre, J.-M.; Pelon, J.; Pettersson, H.; Piguet, B.; Queffeulou, P.; Tailliez, D.; Tournadre, J.; Weill, A.

    2003-03-01

    The "flux, etat de la mer, et télédétection en conditions de fetch variable" (FETCH) was aimed at studying the physical processes associated with air-sea exchanges and mesoscale oceanic circulation in a coastal region dominated by frequent strong offshore winds. The experiment took place in March-April 1998 in the northwestern Mediterranean Sea (Gulf of Lion). Observations were collected with the R/V L'Atalante, with an air-sea interaction spar (ASIS) buoy, with waverider buoys, and with research aircraft equipped for in situ and remote sensing measurements. The present paper is an introduction to the following special section, which groups 12 papers (including this one) presenting results on turbulent flux measurements at the ocean surface, on the behavior of the marine atmospheric boundary layer, on the ocean waves characteristics, on the ocean circulation, and on remote sensing of surface parameters. This overview presents the background and objectives of FETCH, the experimental setup and operations, and the dominant atmospheric and oceanic conditions and introduces the different papers of the special section.

  15. Nicotine Replacement Therapy: An Overview

    PubMed Central

    Wadgave, Umesh; Nagesh, L

    2016-01-01

    Today tobacco use is the single greatest preventable cause of death in the world. Tobacco use is often incorrectly perceived to be solely a personal choice. This is contradicted by the fact that when fully aware of the health impact, most tobacco users want to quit but find it difficult to stop due to the addictiveness of nicotine. Henceforth, Nicotine replacement therapy (NRT) came into existence which temporarily replaces much of the nicotine from tobacco to reduce motivation to consume tobacco and nicotine withdrawal symptoms, thus easing the transition from cigarette smoking to complete abstinence. Various alternative nicotine sources (gum, transdermal patch, nasal spray, inhaler and sublingual tablets/lozenges) have been incorporated into tobacco cessation programs. Recent research is more focusing on rapid delivery of nicotine (Nicotine preloading, true pulmonary inhaler) and immunological approaches (nicotine vaccine) to tackle nicotine dependence. These NRTs are in general well tolerated and have minimal adverse effects. The review aims to summarize literature on various modes of nicotine replacement therapy methods currently used to treat nicotine dependence, and to give an overview about future possible approaches to treat tobacco use disorder. PMID:27610066

  16. Nicotine Replacement Therapy: An Overview.

    PubMed

    Wadgave, Umesh; Nagesh, L

    2016-07-01

    Today tobacco use is the single greatest preventable cause of death in the world. Tobacco use is often incorrectly perceived to be solely a personal choice. This is contradicted by the fact that when fully aware of the health impact, most tobacco users want to quit but find it difficult to stop due to the addictiveness of nicotine. Henceforth, Nicotine replacement therapy (NRT) came into existence which temporarily replaces much of the nicotine from tobacco to reduce motivation to consume tobacco and nicotine withdrawal symptoms, thus easing the transition from cigarette smoking to complete abstinence. Various alternative nicotine sources (gum, transdermal patch, nasal spray, inhaler and sublingual tablets/lozenges) have been incorporated into tobacco cessation programs. Recent research is more focusing on rapid delivery of nicotine (Nicotine preloading, true pulmonary inhaler) and immunological approaches (nicotine vaccine) to tackle nicotine dependence. These NRTs are in general well tolerated and have minimal adverse effects. The review aims to summarize literature on various modes of nicotine replacement therapy methods currently used to treat nicotine dependence, and to give an overview about future possible approaches to treat tobacco use disorder. PMID:27610066

  17. An overview of turbulence compensation

    NASA Astrophysics Data System (ADS)

    Schutte, Klamer; van Eekeren, Adam W. M.; Dijk, Judith; Schwering, Piet B. W.; van Iersel, Miranda; Doelman, Niek J.

    2012-09-01

    In general, long range visual detection, recognition and identification are hampered by turbulence caused by atmospheric conditions. Much research has been devoted to the field of turbulence compensation. One of the main advantages of turbulence compensation is that it enables visual identification over larger distances. In many (military) scenarios this is of crucial importance. In this paper we give an overview of several software and hardware approaches to compensate for the visual artifacts caused by turbulence. These approaches are very diverse and range from the use of dedicated hardware, such as adaptive optics, to the use of software methods, such as deconvolution and lucky imaging. For each approach the pros and cons are given and it is indicated for which type of scenario this approach is useful. In more detail we describe the turbulence compensation methods TNO has developed in the last years and place them in the context of the different turbulence compensation approaches and TNO's turbulence compensation roadmap. Furthermore we look forward and indicate the upcoming challenges in the field of turbulence compensation.

  18. Gender reassignment surgery: an overview.

    PubMed

    Selvaggi, Gennaro; Bellringer, James

    2011-05-01

    Gender reassignment (which includes psychotherapy, hormonal therapy and surgery) has been demonstrated as the most effective treatment for patients affected by gender dysphoria (or gender identity disorder), in which patients do not recognize their gender (sexual identity) as matching their genetic and sexual characteristics. Gender reassignment surgery is a series of complex surgical procedures (genital and nongenital) performed for the treatment of gender dysphoria. Genital procedures performed for gender dysphoria, such as vaginoplasty, clitorolabioplasty, penectomy and orchidectomy in male-to-female transsexuals, and penile and scrotal reconstruction in female-to-male transsexuals, are the core procedures in gender reassignment surgery. Nongenital procedures, such as breast enlargement, mastectomy, facial feminization surgery, voice surgery, and other masculinization and feminization procedures complete the surgical treatment available. The World Professional Association for Transgender Health currently publishes and reviews guidelines and standards of care for patients affected by gender dysphoria, such as eligibility criteria for surgery. This article presents an overview of the genital and nongenital procedures available for both male-to-female and female-to-male gender reassignment. PMID:21487386

  19. An Energy Overview of Bolivia

    SciTech Connect

    anon.

    2003-08-13

    The DOE Office of Fossil Energy maintained a web site that was meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consisted of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There were also more than 30 Country Energy Overviews at the web site -- each of these was a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Bolivia.

  20. An Overview of Canadian Education.

    ERIC Educational Resources Information Center

    Gayfer, Margaret

    The structure and support of Canadian elementary and secondary education is presented with concise descriptions of its organizational structure, administration, curriculum, and special programs. This general overview is appended with organizational charts; directories of provincial, territorial, and federal departments of education; and national…

  1. An Overview of Home Instruction.

    ERIC Educational Resources Information Center

    Lines, Patricia M.

    1987-01-01

    Presents a historical, national, and legal overview of home schooling. Reviews official responses and constitutional limits on state regulation and offers suggestions on ways that public educators and home-schoolers can improve their relationship. Recommends that public officials take initial steps to bridge the communication gap. (CJH)

  2. An Overview of NASA's Mars Science Laboratory

    NASA Technical Reports Server (NTRS)

    Gross, Michael A.; Cardell, Greg

    2011-01-01

    This paper provides a high level overview of NASA's Mars Science Laboratory. Topics to be explored are the Mission's science goals and objectives, a discussion of the mission phases, an overview of the flight system architecture and the payload, and a discussion of the MSL power system.

  3. Overview of dynamical mechanisms of secular evolution

    NASA Astrophysics Data System (ADS)

    Pfenniger, Daniel

    2015-03-01

    Gravity-bound isolated systems, from stars, planetary systems, star clusters to galaxies, share common properties where evolution is the rule. Typically if they start forming at a well defined epoch they tend to change significantly over a timescale comparable to their present age. So evolution is never truly stopped, it just proceeds slower and slower: after a rapid, violent phase a slower, secular phase follows. In galactic astronomy for many decades the paradigm was rather that after a short violent time galaxies would settle in a stable steady state just consuming gas into stars. Actually today it appears that the progressive appearance of galaxy systematic morphologies and the slowing pace of mergers indicate that common intrinsic dynamical factors continue to shape galaxies towards similar properties irrespective of their largely different formation histories and initial conditions. Newtonian physics supplemented by a weakly dissipative component provides an amazing amount of explanations for the galaxy properties, like exponential stellar disks, spirals, bars, and peanut-shaped bulges. The purpose of this talk is to review these mechanisms of dynamical secular evolution.

  4. Biological effects of electric fields: an overview

    SciTech Connect

    Anderson, L.E.; Phillips, R.D.

    1983-11-01

    An overview of the literature suggests tha electric-field exposure is an environmental agent/influence of relatively low potential toxicity to biological systems. Generally, many of the biological effects which have been reported are quite subtle and differences between exposed and unexposed subjects may be masked by normal biological variations. However, several recent reports indicate possibly more serious consequences from chronic exposure, emphasizing the need for more research in epidemiology and laboratory experiments. This paper presents a cursory overview of investigations on the biological consequences of exposure to ELF electromagnetic fields. Three important topics are discussed, including: 1) the general methodology of exposure experiments, including those elements which are critical for definitive studies in biological systems; 2) a brief discussion of epidemiological and clinical studies conducted to date; and 3) a somewhat more extensive examination of animal experiments representing major areas of investigation (behavior, biological rhythms, nervous and endocrine systems, bone growth and repair, cardiovascular system and blood chemistry, immunology, reproduction, growth and development mortality and pathology, cellular and membrane studies, and mutagenesis). A discussion of current concepts, possible mechanisms and future directions of research is presented. 110 references.

  5. The redwood project: An overview

    NASA Technical Reports Server (NTRS)

    Cheatham, Sam

    1993-01-01

    Redwood is a new generation tape subsystem now under development at StorageTek using helical scan technology. This library based storage subsystem is designed for the high performance, deep archival market. The topics are presented in viewgraph form and include the following: subsystem overview, media standards, Redwood developed tape, D3 helical recording format, Redwood cartridge, host software for Redwood libraries, and market opportunities.

  6. Nickel hydrogen batteries: An overview

    NASA Technical Reports Server (NTRS)

    Smithrick, John J.; Odonnell, Patricia M.

    1994-01-01

    This paper on nickel hydrogen batteries is an overview of the various nickel hydrogen battery design options, technical accomplishments, validation test results and trends. There is more than one nickel hydrogen battery design, each having its advantage for specific applications. The major battery designs are individual pressure vessel (IPV), common pressure vessel (CPV), bipolar and low pressure metal hydride. State-of-the-art (SOA) nickel hydrogen batteries are replacing nickel cadmium batteries in almost all geosynchronous orbit (GEO) applications requiring power above 1 kW. However, for the more severe low earth orbit (LEO) applications (greater than 30,000 cycles), the current cycle life of 4000 to 10,000 cycles at 60 percent DOD should be improved. A LeRC innovative advanced design IPV nickel hydrogen cell led to a breakthrough in cycle life enabling LEO applications at deep depths of discharge (DOD). A trend for some future satellites is to increase the power level to greater than 6 kW. Another trend is to decrease the power to less than 1 kW for small low cost satellites. Hence, the challenge is to reduce battery mass,volume, and cost. A key is to develop a light weight nickel electrode and alternate battery designs. A common pressure vessel (CPV) nickel hydrogen battery is emerging as a viable alternative to the IPV design. It has the advantage of reduced mass, volume and manufacturing costs. A 10 Ah CPV battery has successfully provided power on the relatively short lived Clementine Spacecraft. A bipolar nickel hydrogen battery design has been demonstrated (15,000 LEO cycles, 40 percent DOD). The advantage is also a significant reduction in volume, a modest reduction in mass, and like most bipolar designs, features a high pulse power capability. A low pressure aerospace nickel metal hydride battery cell has been developed and is on the market. It is a prismatic design which has the advantage of a significant reduction in volume and a reduction in

  7. An overview of gravitational physiology

    NASA Technical Reports Server (NTRS)

    Miquel, Jaime; Souza, Kenneth A.

    1991-01-01

    The focus of this review is on the response of humans and animals to the effects of the near weightless condition occurring aboard orbiting spacecraft. Gravity is an omnipresent force that has been a constant part of our lives and of the evolution of all living species. Emphasis is placed on the general mechanisms of adaptation to altered gravitational fields and vectors, i.e., both hypo- and hypergravity. A broad literature review of gravitational biology was conducted and the general state of our knowledge in this area is discussed. The review is specifically targeted at newcomers to the exciting and relatively new area of space and gravitational biology.

  8. Epithelial ovarian cancer: An overview

    PubMed Central

    Desai, Arpita; Xu, Jingyao; Aysola, Kartik; Qin, Yunlong; Okoli, Chika; Hariprasad, Ravipati; Chinemerem, Ugorji; Gates, Candace; Reddy, Avinash; Danner, Omar; Franklin, Geary; Ngozi, Anachebe; Cantuaria, Guilherme; Singh, Karan; Grizzle, William; Landen, Charles; Partridge, Edward E; Rice, Valerie Montgomery; Reddy, E Shyam P; Rao, Veena N

    2014-01-01

    Ovarian cancer is the second most common gynecological cancer and the leading cause of death in the United States. In this article we review the diagnosis and current management of epithelial ovarian cancer which accounts for over 95 percent of the ovarian malignancies. We will present various theories about the potential origin of ovarian malignancies. We will discuss the genetic anomalies and syndromes that may cause ovarian cancers with emphasis on Breast cancer type 1/2 mutations. The pathology and pathogenesis of ovarian carcinoma will also be presented. Lastly, we provide a comprehensive overview of treatment strategies and staging of ovarian cancer, conclusions and future directions. PMID:25525571

  9. Loop quantum cosmology: an overview

    NASA Astrophysics Data System (ADS)

    Ashtekar, Abhay

    2009-04-01

    A brief overview of loop quantum cosmology of homogeneous isotropic models is presented with emphasis on the origin of and subtleties associated with the resolution of big bang and big crunch singularities. These results bear out the remarkable intuition that John Wheeler had. Discussion is organized at two levels. The the main text provides a bird’s eye view of the subject that should be accessible to non-experts. Appendices address conceptual and technical issues that are often raised by experts in loop quantum gravity and string theory.

  10. An overview of osteocalcin progress.

    PubMed

    Li, Jinqiao; Zhang, Hongyu; Yang, Chao; Li, Yinghui; Dai, Zhongquan

    2016-07-01

    An increasing amount of data indicate that osteocalcin is an endocrine hormone which regulates energy metabolism, male fertility and brain development. However, the detailed functions and mechanism of osteocalcin are not well understood and conflicting results have been obtained from researchers worldwide. In the present review, we summarize the progress of osteocalcin studies over the past 40 years, focusing on the structure of carboxylated and undercarboxylated osteocalcin, new functions and putative receptors, the role of osteocalcin in bone remodeling, specific expression and regulation in osteoblasts, and new indices for clinical studies. The complexity of osteocalcin in completely, uncompletely and non-carboxylated forms may account for the discrepancies in its tertiary structure and clinical results. Moreover, the extensive expression of osteocalcin and its putative receptor GPRC6A imply that there are new physiological functions and mechanisms of action of osteocalcin to be explored. New discoveries related to osteocalcin function will assist its potential clinical application and physiological theory, but comprehensive investigations are required. PMID:26747614

  11. Wind Turbine Drivetrain Condition Monitoring - An Overview

    SciTech Connect

    Sheng, S; Veers, P.

    2011-10-01

    This paper provides an overview of wind turbine drivetrain condition monitoring based on presentations from a condition monitoring workshop organized by the National Renewable Energy Laboratory in 2009 and on additional references.

  12. The NASA Geodynamics Program: An overview

    NASA Technical Reports Server (NTRS)

    1983-01-01

    This NASA Geodynamics Program overview collectively examines the history, scientific basis, status, and results of the NASA Program and outlines plans for the next five to eight years. It is intended as an informative nontechnical discussion of geodynamics research.

  13. Chemical ecology of marine organisms: an overview

    SciTech Connect

    Bakus, G.V.; Schutte, B.; Targett, N.M.

    1986-05-01

    An overview of marine chemical ecology is presented. Emphasis is placed on antipredation, invertebrate-toxic host relationships, antifouling, competition for space, species dominance, and the chemistry of ecological interactions.

  14. Results of coronal hole research: An overview

    NASA Technical Reports Server (NTRS)

    Wilson, R. M.

    1976-01-01

    An overview of the last 10 years of coronal hole research, in particular since 1970, is presented. The findings of the early investigations and the more recent results obtained with Skylab/Apollo Telescope Mount instrumentation are discussed.

  15. Energy efficient drivepower: An overview

    NASA Astrophysics Data System (ADS)

    Ula, Sadrul; Birnbaum, Larry E.; Jordan, Don

    Energy efficiency is a major concern to industry for a variety of reasons. Operating expenses and public relations are just two of these. While a lot of effort has been expended in the area of electrical energy efficiency, the area of concern in the report, most papers use a limited approach when examining the opportunities for efficiency improvement. However, use of a systems approach--examining the entire power train system from when electrical power first enters a facility to the final output is presented. This type of approach to electrical energy efficiency can improve the overall efficiency by a significant amount. There are many methods of driving mechanical loads such as waste steam (steam turbine), centralized hydraulic systems, and compressed air. Only electric-drive systems were analyzed. Depending on the application and facilities, these other methods may be a viable alternative to electric drivepower systems. The document assumes that the reader has an understanding of the basic concepts, practices, and terminology used in electrical and mechanical engineering. The reader should be familiar with terms such as voltage, current, dc power, ac power, power factor, horse power, torque, angular velocity, kilowatt-hours, efficiency, harmonics, and gear ratio.

  16. Imiquimod in dermatology: an overview.

    PubMed

    Hanna, Edith; Abadi, Rami; Abbas, Ossama

    2016-08-01

    Imiquimod is an immune response modifier commercially available as a 3.75 and 5% cream. Topical imiquimod stimulates the innate and adaptive immune responses and induces cytokine production. This allows its use for the treatment of a wide variety of benign and malignant skin conditions due to its potential antiviral, antitumor, and immunoregulatory effects. Currently, topical imiquimod is US Food and Drug Administration (FDA)-approved for the treatment of anogenital warts, actinic keratosis, and superficial basal cell carcinomas. However, it has also shown a beneficial effect in the treatment of many other skin disorders. In this review, we describe existing evidence on the mechanism of action of topical imiquimod, its FDA-approved indications, off-label uses, and side effects. PMID:27387373

  17. An overview of internet biosurveillance.

    PubMed

    Hartley, D M; Nelson, N P; Arthur, R R; Barboza, P; Collier, N; Lightfoot, N; Linge, J P; van der Goot, E; Mawudeku, A; Madoff, L C; Vaillant, L; Walters, R; Yangarber, R; Mantero, J; Corley, C D; Brownstein, J S

    2013-11-01

    Internet biosurveillance utilizes unstructured data from diverse web-based sources to provide early warning and situational awareness of public health threats. The scope of source coverage ranges from local media in the vernacular to international media in widely read languages. Internet biosurveillance is a timely modality that is available to government and public health officials, healthcare workers, and the public and private sector, serving as a real-time complementary approach to traditional indicator-based public health disease surveillance methods. Internet biosurveillance also supports the broader activity of epidemic intelligence. This overview covers the current state of the field of Internet biosurveillance, and provides a perspective on the future of the field. PMID:23789639

  18. Sodium and water: an overview.

    PubMed

    Papper, S

    1976-01-01

    The renal regulation of sodium is intertwined with the extracellular fluid volume (ECFV). Most adjustments in sodium elimination in man are accomplished via alterations in tubular reabsorption. The latter is sensitive to change in ECFV. An expanded ECFV results in less reabsorption and more excretion of sodium, and a contracted ECFV has the converse effect. There are direct and indirect mechanisms whereby ECFV influences sodium reabsorption. Patients with nephrotic syndrome, heart failure, and cirrhosis "behave" physiologically as normal individuals with a contracted ECFV. Water balance is normally determined by intake and losses in sweat which is always hypoosmotic to plasma, by evaporation from skin and lungs, and through renal excretion. The major factors that determine the ability to concentrate the urine are (1) the establishment of a concentrated environment around the collecting ducts, and (2) the elaboration and effects on the kidney of antidiuretic hormone. The evaluation of a patient with abnormalities of sodium and water rests initially and largely on clinical information. The clinical setting provides clues to anticipating, preventing, and interpreting distortions of body sodium and water. The laboratory can detect an abnormality, confirm or refute clinical assessment, and assist in the quantitative aspects of treatment and its efficacy. PMID:961714

  19. An Energy Overview of the Czech Republic

    SciTech Connect

    anon.

    2003-10-17

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is the Czech Republic. The site is designed to be dynamic. Updates to the overviews will be made as need an d resources permit.

  20. The STEREO Mission: An Overview

    NASA Astrophysics Data System (ADS)

    Kaiser, M. L.

    2004-12-01

    In February 2006, NASA will launch the twin STEREO spacecraft from Kennedy Space Center aboard a Delta 7925 launch vehicle. After a series of highly eccentric Earth orbits with apogees beyond the moon, each spacecraft will use close flybys of the moon to escape into heliocentric orbits at 1 AU, with one spacecraft trailing Earth and the other leading Earth. As viewed from the sun, the two spacecraft will separate at approximately 45 degrees per year. The purposes of the STEREO Mission are to understand the causes and mechanisms of CME initiation and to follow the propagation of CMEs through the heliosphere. Additionally, STEREO will study the mechanisms and sites of energetic particle acceleration and determine 3-D time-dependent traces of the magnetic topology, temperature, density and velocity of the solar wind between the sun and Earth. To accomplish these goals, each STEREO spacecraft will be equipped with set of optical, radio and in situ particles and fields instruments. The SECCHI suite of instruments includes two white light coronagraphs covering the range from 1.4 to 15 solar radii, an extreme ultra violet imager covering the chromosphere and inner corona, and two heliospheric white light imagers covering the outer corona from 12 solar radii to 1 AU. The IMPACT suite of instruments will measure in situ solar wind electrons in the energy range from essentially 0 to 100 keV, energetic electrons to 6 MeV, and protons and heavier ions to 100 MeV/nucleon. IMPACT also contains a magnetometer to measure the in situ magnetic field strength and direction. The PLASTIC instrument will measure the composition of heavy ions as well as protons and alpha particles. The SWAVES instrument will use radio waves to track the location of CME-driven shocks and the 3-D topology of open field lines along which energetic particles flow. Additionally, SWAVES will measure in situ plasma waves to provide an independent estimate of the local plasma density and temperature. Each of the

  1. An overview of semantic compression

    NASA Astrophysics Data System (ADS)

    Schmalz, Mark S.

    2010-08-01

    We live in such perceptually rich natural and manmade environments that detection and recognition of objects is mediated cerebrally by attentional filtering, in order to separate objects of interest from background clutter. In computer models of the human visual system, attentional filtering is often restricted to early processing, where areas of interest (AOIs) are delineated around anomalies of interest, then the pixels within each AOI's subtense are isolated for later processing. In contrast, the human visual system concurrently detects many targets at multiple levels (e.g., retinal center-surround filters, ganglion layer feature detectors, post-retinal spatial filtering, and cortical detection / filtering of features and objects, to name but a few processes). Intracranial attentional filtering appears to play multiple roles, including clutter filtration at all levels of processing - thus, we process individual retinal cell responses, early filtering response, and so forth, on up to the filtering of objects at high levels of semantic complexity. Computationally, image compression techniques have progressed from emphasizing pixels, to considering regions of pixels as foci of computational interest. In more recent research, object-based compression has been investigated with varying rate-distortion performance and computational efficiency. Codecs have been developed for a wide variety of applications, although the majority of compression and decompression transforms continue to concentrate on region- and pixel-based processing, in part because of computational convenience. It is interesting to note that a growing body of research has emphasized the detection and representation of small features in relationship to their surrounding environment, which has occasionally been called semantic compression. In this paper, we overview different types of semantic compression approaches, with particular interest in high-level compression algorithms. Various algorithms and

  2. An overview of acoustic telemetry

    SciTech Connect

    Drumheller, D.S.

    1992-01-01

    Acoustic telemetry has been a dream of the drilling industry for the past 50 years. It offers the promise of data rates which are one-hundred times greater than existing technology. Such a system would open the door to true logging-while-drilling technology and bring enormous profits to its developers. The basic idea is to produce an encoded sound wave at the bottom of the well, let it propagate up the steel drillpipe, and extract the data from the signal at the surface. Unfortunately, substantial difficulties arise. The first difficult problem is to produce the sound wave. Since the most promising transmission wavelengths are about 20 feet, normal transducer efficiencies are quire low. Compounding this problem is the structural complexity of the bottomhole assembly and drillstring. For example, the acoustic impedance of the drillstring changes every 30 feet and produces an unusual scattering pattern in the acoustic transmission. This scattering pattern causes distortion of the signal and is often confused with signal attenuation. These problems are not intractable. Recent work has demonstrated that broad frequency bands exist which are capable of transmitting data at rates up to 100 bits per second. Our work has also identified the mechanism which is responsible for the observed anomalies in the patterns of signal attenuation. Furthermore in the past few years a body of experience has been developed in designing more efficient transducers for application to metal waveguides. The direction of future work is clear. New transducer designs which are more efficient and compatible with existing downhole power supplies need to be built and tested; existing field test data need to be analyzed for transmission bandwidth and attenuation; and the new and less expensive methods of collecting data on transmission path quality need to be incorporated into this effort. 11 refs.

  3. Exercise and asthma: an overview

    PubMed Central

    Giacco, Stefano R. Del; Firinu, Davide; Bjermer, Leif; Carlsen, Kai-Håkon

    2015-01-01

    The terms ‘exercise-induced asthma’ (EIA) and ‘exercise-induced bronchoconstriction’ (EIB) are often used interchangeably to describe symptoms of asthma such as cough, wheeze, or dyspnoea provoked by vigorous physical activity. In this review, we refer to EIB as the bronchoconstrictive response and to EIA when bronchoconstriction is associated with asthma symptoms. EIB is a common occurrence for most of the asthmatic patients, but it also affects more than 10% of otherwise healthy individuals as shown by epidemiological studies. EIA and EIB have a high prevalence also in elite athletes, especially within endurance type of sports, and an athlete's asthma phenotype has been described. However, the occurrence in elite athletes shows that EIA/EIB, if correctly managed, may not impair physical activity and top sports performance. The pathogenic mechanisms of EIA/EIB classically involve both osmolar and vascular changes in the airways in addition to cooling of the airways with parasympathetic stimulation. Airways inflammation plays a fundamental role in EIA/EIB. Diagnosis and pharmacological management must be carefully performed, with particular consideration of current anti-doping regulations, when caring for athletes. Based on the demonstration that the inhaled asthma drugs do not improve performance in healthy athletes, the doping regulations are presently much less strict than previously. Some sports are at a higher asthma risk than others, probably due to a high environmental exposure while performing the sport, with swimming and chlorine exposure during swimming as one example. It is considered very important for the asthmatic child and adolescent to master EIA/EIB to be able to participate in physical activity on an equal level with their peers, and a precise early diagnosis with optimal treatment follow-up is vital in this aspect. In addition, surprising recent preliminary evidences offer new perspectives for moderate exercise as a potential therapeutic

  4. Exercise and asthma: an overview.

    PubMed

    Del Giacco, Stefano R; Firinu, Davide; Bjermer, Leif; Carlsen, Kai-Håkon

    2015-01-01

    The terms 'exercise-induced asthma' (EIA) and 'exercise-induced bronchoconstriction' (EIB) are often used interchangeably to describe symptoms of asthma such as cough, wheeze, or dyspnoea provoked by vigorous physical activity. In this review, we refer to EIB as the bronchoconstrictive response and to EIA when bronchoconstriction is associated with asthma symptoms. EIB is a common occurrence for most of the asthmatic patients, but it also affects more than 10% of otherwise healthy individuals as shown by epidemiological studies. EIA and EIB have a high prevalence also in elite athletes, especially within endurance type of sports, and an athlete's asthma phenotype has been described. However, the occurrence in elite athletes shows that EIA/EIB, if correctly managed, may not impair physical activity and top sports performance. The pathogenic mechanisms of EIA/EIB classically involve both osmolar and vascular changes in the airways in addition to cooling of the airways with parasympathetic stimulation. Airways inflammation plays a fundamental role in EIA/EIB. Diagnosis and pharmacological management must be carefully performed, with particular consideration of current anti-doping regulations, when caring for athletes. Based on the demonstration that the inhaled asthma drugs do not improve performance in healthy athletes, the doping regulations are presently much less strict than previously. Some sports are at a higher asthma risk than others, probably due to a high environmental exposure while performing the sport, with swimming and chlorine exposure during swimming as one example. It is considered very important for the asthmatic child and adolescent to master EIA/EIB to be able to participate in physical activity on an equal level with their peers, and a precise early diagnosis with optimal treatment follow-up is vital in this aspect. In addition, surprising recent preliminary evidences offer new perspectives for moderate exercise as a potential therapeutic tool for

  5. An overview of health forecasting.

    PubMed

    Soyiri, Ireneous N; Reidpath, Daniel D

    2013-01-01

    Health forecasting is a novel area of forecasting, and a valuable tool for predicting future health events or situations such as demands for health services and healthcare needs. It facilitates preventive medicine and health care intervention strategies, by pre-informing health service providers to take appropriate mitigating actions to minimize risks and manage demand. Health forecasting requires reliable data, information and appropriate analytical tools for the prediction of specific health conditions or situations. There is no single approach to health forecasting, and so various methods have often been adopted to forecast aggregate or specific health conditions. Meanwhile, there are no defined health forecasting horizons (time frames) to match the choices of health forecasting methods/approaches that are often applied. The key principles of health forecasting have not also been adequately described to guide the process. This paper provides a brief introduction and theoretical analysis of health forecasting. It describes the key issues that are important for health forecasting, including: definitions, principles of health forecasting, and the properties of health data, which influence the choices of health forecasting methods. Other matters related to the value of health forecasting, and the general challenges associated with developing and using health forecasting services are discussed. This overview is a stimulus for further discussions on standardizing health forecasting approaches and methods that will facilitate health care and health services delivery. PMID:22949173

  6. Human saliva proteome: an overview

    NASA Astrophysics Data System (ADS)

    Griffin, Timothy J.

    2014-06-01

    Human saliva contains a rich mixture of biomolecules. Proteins are a major component of this mixture. Given their role as the molecular effectors within biological systems, ranging from catalysis to transport to structure, proteins have great potential as biomarkers of health and disease. The ability to collect these salivary biomarkers easily using non-invasive means makes saliva proteins even more attractive for diagnostic applications. Thousands of proteins are now to be known to be present in human saliva - discovered using proteomic technologies. Emerging technologies are now making it possible to go beyond large-scale cataloging of salivary proteins. These include approaches to catalog protein contributions from the community of microorganisms residing in the oral cavity (metaproteomics) that may reflect the health state of the human host. New mass spectrometry-based proteomics methods are also emerging, shifting the emphasis from large-scale discovery experiments to hypothesis-driven assays for profiling proteins of interest within saliva, enabling validation of their association with specific health conditions. This paper provides a brief overview of efforts to catalog the proteome of human saliva. Recent developments making possible characterization of the metaproteome of human saliva will be discussed, and technologies driving new mass spectrometry-based assays for targeted analysis of proteins within complex samples, such as saliva.

  7. An Overview of Acoustic Telemetry

    SciTech Connect

    Drumheller, D.S.

    1992-03-24

    Acoustic telemetry has been a dream of the drilling industry for the past 50 years. It offers the promise of data rates which are one-hundred times greater than existing technology. Such a system would open the door to true logging-while-drilling technology and bring enormous profits to its developers. The oil and gas industry has led in most of the attempts to develop this type of telemetry system; however, very substantial efforts have also been made through government sponsored work in the geothermal industry. None of these previous attempts have lead to a commercial telemetry system. Conceptually, the problem looks easy. The basic idea is to produce an encoded sound wave at the bottom of the well, let it propagate up the steel drillpipe, and extract the data from the signal at the surface. Unfortunately, substantial difficulties arise. The first difficult problem is to produce the sound wave. Since the most promising transmission wavelengths are about 20 feet, normal transducer efficiencies are quite low. Compounding this problem is the structural complexity of the bottomhole assembly and drillstring. For example, the acoustic impedance of the drillstring changes every 30 feet and produces an unusual scattering pattern in the acoustic transmission. This scattering pattern causes distortion of the signal and is often confused with signal attenuation. These problems are not intractable. Recent work has demonstrated that broad frequency bands exist which are capable of transmitting data at rates up to 100 bits per second. Our work has also identified the mechanism which is responsible for the observed anomalies in the patterns of signal attenuation. Furthermore in the past few years a body of experience has been developed in designing more efficient transducers for application to metal Waveguides. The direction of future work is clear. New transducer designs which are more efficient and compatible with existing downhole power supplies need to be built and tested

  8. An overview of the Penn State Propulsion Engineering Research Center

    NASA Technical Reports Server (NTRS)

    Merkle, Charles L.

    1991-01-01

    An overview of the Penn State Propulsion Engineering Research Center is presented. The following subject areas are covered: research objectives and long term perspective of the Center; current status and operational philosophy; and brief description of Center projects (combustion, fluid mechanics and heat transfer, materials compatibility, turbomachinery, and advanced propulsion concepts).

  9. Antimalarial drug resistance: An overview.

    PubMed

    Antony, Hiasindh Ashmi; Parija, Subhash Chandra

    2016-01-01

    Malaria is a major public health burden throughout the world. Resistance to the antimalarial drugs has increased the mortality and morbidity rate that is achieved so far through the malaria control program. Monitoring the drug resistance to the available antimalarial drugs helps to implement effective drug policy, through the in vivo efficacy studies, in vitro drug susceptibility tests and detection of molecular markers. It is important to understand the mechanism of the antimalarial drugs, as it is one of the key factors in the emergence and spread of drug resistance. This review summarizes the commonly used antimalarial drugs, their mechanism of action and the genetic markers validated so far for the detection of drug-resistant parasites. PMID:26998432

  10. Antimicrobial photodynamic therapy: An overview

    PubMed Central

    Rajesh, S.; Koshi, Elizabeth; Philip, Koshi; Mohan, Aparna

    2011-01-01

    Inflammatory periodontal disease caused by dental plaque is characterized by the clinical signs of inflammation and loss of periodontal tissue support. The mechanical removal of this biofilm and adjunctive use of antibacterial disinfectants and antibiotics have been the conventional methods of periodontal therapy. But the removal of plaque and the reduction in the number of infectious organisms can be impaired in sites with difficult access. The possibility of development of resistance to antibiotics by the target organism has led to the development of a new antimicrobial concept with fewer complications. Photodynamic therapy (PDT) involves the use of low power lasers with appropriate wavelength to kill micro organisms treated with a photosensitizer drug. PDT could be a useful adjunct to mechanical as well as antibiotics in eliminating periopathogenic bacteria. PMID:22368354

  11. Antimalarial drug resistance: An overview

    PubMed Central

    Antony, Hiasindh Ashmi; Parija, Subhash Chandra

    2016-01-01

    Malaria is a major public health burden throughout the world. Resistance to the antimalarial drugs has increased the mortality and morbidity rate that is achieved so far through the malaria control program. Monitoring the drug resistance to the available antimalarial drugs helps to implement effective drug policy, through the in vivo efficacy studies, in vitro drug susceptibility tests and detection of molecular markers. It is important to understand the mechanism of the antimalarial drugs, as it is one of the key factors in the emergence and spread of drug resistance. This review summarizes the commonly used antimalarial drugs, their mechanism of action and the genetic markers validated so far for the detection of drug-resistant parasites. PMID:26998432

  12. Surface Characterization Techniques: An Overview

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    2002-01-01

    To understand the benefits that surface modifications provide, and ultimately to devise better ones, it is necessary to study the physical, mechanical, and chemical changes they cause. This chapter surveys classical and leading-edge developments in surface structure and property characterization methodologies. The primary emphases are on the use of these techniques as they relate to surface modifications, thin films and coatings, and tribological engineering surfaces and on the implications rather than the instrumentation.

  13. Energy Efficient Drivepower: An Overview.

    SciTech Connect

    Ula, Sadrul; Birnbaum, Larry E.; Jordan, Don

    1993-05-01

    This report examines energy efficiency in drivepower systems. Only systems where the prime movers are electrical motors are discussed. A systems approach is used to examine all major aspects of drivepower, including motors, controls, electrical tune-ups, mechanical efficiency, maintenance, and management. Potential annual savings to the US society of $25 to $50 billion are indicated. The report was written for readers with a semi-technical background.

  14. An overview of benzene metabolism

    SciTech Connect

    Snyder, R.; Hedli, C.C.

    1996-12-01

    Benzene toxicity involves both bone marrow depression and leukemogenesis caused by damage to multiple classes of hematopoietic cells and a variety of hematopoietic cell functions. Study of the relationship between the metabolism and toxicity of benzene indicates that several metabolites of benzene play significant roles in generating benzene toxicity. Benzene is metabolized, primarily in the liver, to a variety of hydroxylated and ring-opened products that are transported to the bone marrow where subsequent secondary metabolism occurs. Two potential mechanisms by which benzene metabolites may damage cellular macromolecules to induce toxicity include the covalent binding of reactive metabolites of benzene and the capacity of benzene metabolites to induce oxidative damage. Although the relative contributions of each of these mechanisms to toxicity remains unestablished, it is clear that different mechanisms contribute to the toxicities; associated with different metabolites. As a corollary, it is unlikely that benzene toxicity can be described as the result of the interaction of a single metabolite with a single biological target. Continued investigation of the metabolism of benzene and its metabolites will allow us to determine the specific combination of metabolites as well as the biological target(s) involved in toxicity and will ultimately lead to our understanding of the relationship between the production of benzene metabolites and bone marrow toxicity. 52 refs., 9 figs., 5 tabs.

  15. An overview of benzene metabolism.

    PubMed Central

    Snyder, R; Hedli, C C

    1996-01-01

    Benzene toxicity involves both bone marrow depression and leukemogenesis caused by damage to multiple classes of hematopoietic cells and a variety of hematopoietic cell functions. Study of the relationship between the metabolism and toxicity of benzene indicates that several metabolites of benzene play significant roles in generating benzene toxicity. Benzene is metabolized, primarily in the liver, to a variety of hydroxylated and ring-opened products that are transported to the bone marrow where subsequent secondary metabolism occurs. Two potential mechanisms by which benzene metabolites may damage cellular macromolecules to induce toxicity include the covalent binding of reactive metabolites of benzene and the capacity of benzene metabolites to induce oxidative damage. Although the relative contributions of each of these mechanisms to toxicity remains unestablished, it is clear that different mechanisms contribute to the toxicities associated with different metabolites. As a corollary, it is unlikely that benzene toxicity can be described as the result of the interaction of a single metabolite with a single biological target. Continued investigation of the metabolism of benzene and its metabolites will allow us to determine the specific combination of metabolites as well as the biological target(s) involved in toxicity and will ultimately lead to our understanding of the relationship between the production of benzene metabolites and bone marrow toxicity. PMID:9118888

  16. An interim overview of LDEF materials findings

    SciTech Connect

    Stein, B.A.

    1992-12-01

    The flight and retrieval of the National Aeronautics and Space Administration's Long Duration Exposure Facility (LDEF) provided an opportunity for the study of the low-Earth orbit (LEO) environment and long-duration space environmental effects (SEE) on materials that is unparalleled in the history of the U.S. Space Program. The remarkable flight attitude stability of LDEF enables specific analyses of various individual and combined effects of LEO environmental parameters on identical materials on the same space vehicle. This paper provides an overview of the interim LDEF materials findings of the Principal Investigators and the Materials Special Investigation Group. In general, the LDEF data is remarkably consistent; LDEF will provide a benchmark for materials design data bases for satellites in low-Earth orbit. Some materials were identified to be encouragingly resistant to LEO SEE for 5.8 years; other space qualified materials displayed significant environmental degradation. Molecular contamination was widespread; LDEF offers an unprecedented opportunity to provide a unified perspective of unmanned LEO spacecraft contamination mechanisms. New material development requirements for long-term LEO missions have been identified and current ground simulation testing methods/data for new, durable materials concepts can be validated with LDEF results. LDEF findings are already being integrated into the design of Space Station Freedom.

  17. An interim overview of LDEF materials findings

    NASA Technical Reports Server (NTRS)

    Stein, Brad A.

    1992-01-01

    The flight and retrieval of the National Aeronautics and Space Administration's Long Duration Exposure Facility (LDEF) provided an opportunity for the study of the low-Earth orbit (LEO) environment and long-duration space environmental effects (SEE) on materials that is unparalleled in the history of the U.S. Space Program. The remarkable flight attitude stability of LDEF enables specific analyses of various individual and combined effects of LEO environmental parameters on identical materials on the same space vehicle. This paper provides an overview of the interim LDEF materials findings of the Principal Investigators and the Materials Special Investigation Group. In general, the LDEF data is remarkably consistent; LDEF will provide a 'benchmark' for materials design data bases for satellites in low-Earth orbit. Some materials were identified to be encouragingly resistant to LEO SEE for 5.8 years; other 'space qualified' materials displayed significant environmental degradation. Molecular contamination was widespread; LDEF offers an unprecedented opportunity to provide a unified perspective of unmanned LEO spacecraft contamination mechanisms. New material development requirements for long-term LEO missions have been identified and current ground simulation testing methods/data for new, durable materials concepts can be validated with LDEF results. LDEF findings are already being integrated into the design of Space Station Freedom.

  18. Structural biological composites: An overview

    NASA Astrophysics Data System (ADS)

    Meyers, Marc A.; Lin, Albert Y. M.; Seki, Yasuaki; Chen, Po-Yu; Kad, Bimal K.; Bodde, Sara

    2006-07-01

    Biological materials are complex composites that are hierarchically structured and multifunctional. Their mechanical properties are often outstanding, considering the weak constituents from which they are assembled. They are for the most part composed of brittle (often, mineral) and ductile (organic) components. These complex structures, which have risen from millions of years of evolution, are inspiring materials scientists in the design of novel materials. This paper discusses the overall design principles in biological structural composites and illustrates them for five examples; sea spicules, the abalone shell, the conch shell, the toucan and hornbill beaks, and the sheep crab exoskeleton.

  19. Telescope structures - An evolutionary overview

    NASA Technical Reports Server (NTRS)

    Meinel, Aden B.; Meinel, Marjorie P.

    1987-01-01

    A development history is presented for telescope structural support materials, design concepts, equatorial and altazimuthal orientational preferences, and mechanical control system structural realizations. In the course of 50 years after Galileo, the basic configurations of all reflecting telescopes was set for the subsequent 300 years: these were the Cassegrain, Gregorian, and Newtonian designs. The challenge of making a lightweight ribbed pyrex glass primary mirror for the 5-m Palomar telescope was met by von Karman's use of finite element analysis. Attention is given to the prospects for a 20-m deployable space-based reflecting telescope.

  20. Dengue viruses – an overview

    PubMed Central

    Bäck, Anne Tuiskunen; Lundkvist, Åke

    2013-01-01

    Dengue viruses (DENVs) cause the most common arthropod-borne viral disease in man with 50–100 million infections per year. Because of the lack of a vaccine and antiviral drugs, the sole measure of control is limiting the Aedes mosquito vectors. DENV infection can be asymptomatic or a self-limited, acute febrile disease ranging in severity. The classical form of dengue fever (DF) is characterized by high fever, headache, stomach ache, rash, myalgia, and arthralgia. Severe dengue, dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS) are accompanied by thrombocytopenia, vascular leakage, and hypotension. DSS, which can be fatal, is characterized by systemic shock. Despite intensive research, the underlying mechanisms causing severe dengue is still not well understood partly due to the lack of appropriate animal models of infection and disease. However, even though it is clear that both viral and host factors play important roles in the course of infection, a fundamental knowledge gap still remains to be filled regarding host cell tropism, crucial host immune response mechanisms, and viral markers for virulence. PMID:24003364

  1. Psychiatric Evaluation in Dermatology: An Overview

    PubMed Central

    Ghosh, Sreyoshi; Behere, Rishikesh V; Sharma, PSVN; Sreejayan, K

    2013-01-01

    Psychodermatology is an exciting field which deals with the close relationship that exists between dermatological and psychiatric disorders. A combined bio-psycho-social approach is essential for effective evaluation and treatment of these conditions. This review aims to give the practicing clinician an overview of psychiatric evaluation in patients with dermatological conditions. PMID:23372211

  2. Beam transfer at E0: An overview

    SciTech Connect

    Saritepe, S.; Annala, G.

    1993-06-25

    The helical orbits in the Tevatron necessitated changes in the beam transfer operation between the Main Ring and the Tevatron. This document is intended to present an overview of the beam transfer with an emphasis on the recent changes. It will also serve as a bibliography for the other documents that exist on Tevatron injection.

  3. Interferometric Synthetic Aperture Microwave Radiometers : an Overview

    NASA Technical Reports Server (NTRS)

    Colliander, Andreas; McKague, Darren

    2011-01-01

    This paper describes 1) the progress of the work of the IEEE Geoscience and Remote Sensing Society (GRSS) Instrumentation and Future Technologies Technical Committee (IFT-TC) Microwave Radiometer Working Group and 2) an overview of the development of interferometric synthetic aperture microwave radiometers as an introduction to a dedicated session.

  4. Dictionaries of African Sign Languages: An Overview

    ERIC Educational Resources Information Center

    Schmaling, Constanze H.

    2012-01-01

    This article gives an overview of dictionaries of African sign languages that have been published to date most of which have not been widely distributed. After an introduction into the field of sign language lexicography and a discussion of some of the obstacles that authors of sign language dictionaries face in general, I will show problems…

  5. World Wide Web Robots: An Overview.

    ERIC Educational Resources Information Center

    Chun, Tham Yoke

    1999-01-01

    Traces the development of World Wide Web Robots and provides an overview of their main functions and workings. The focus is on search robots. Illustrations are drawn from two major search engines: AltaVista and Excite. Concludes with an examination of problems associated with the use of Web Robots and their implications for electronic publishing.…

  6. An overview of cardiac morphogenesis.

    PubMed

    Schleich, Jean-Marc; Abdulla, Tariq; Summers, Ron; Houyel, Lucile

    2013-11-01

    Accurate knowledge of normal cardiac development is essential for properly understanding the morphogenesis of congenital cardiac malformations that represent the most common congenital anomaly in newborns. The heart is the first organ to function during embryonic development and is fully formed at 8 weeks of gestation. Recent studies stemming from molecular genetics have allowed specification of the role of cellular precursors in the field of heart development. In this article we review the different steps of heart development, focusing on the processes of alignment and septation. We also show, as often as possible, the links between abnormalities of cardiac development and the main congenital heart defects. The development of animal models has permitted the unraveling of many mechanisms that potentially lead to cardiac malformations. A next step towards a better knowledge of cardiac development could be multiscale cardiac modelling. PMID:24138816

  7. Hematopoietic stem cells: an overview.

    PubMed

    Mosaad, Youssef Mohamed

    2014-12-01

    Considerable efforts have been made in recent years in understanding the mechanisms that govern hematopoietic stem cell (HSC) origin, development, differentiation, self-renewal, aging, trafficking, plasticity and transdifferentiation. Hematopoiesis occurs in sequential waves in distinct anatomical locations during development and these shifts in location are accompanied by changes in the functional status of the stem cells and reflect the changing needs of the developing organism. HSCs make a choice of either self-renewal or committing to differentiation. The balance between self-renewal and differentiation is considered to be critical to the maintenance of stem cell numbers. It is still under debate if HSC can rejuvenate infinitely or if they do not possess ''true" self-renewal and undergo replicative senescence such as any other somatic cell. Gene therapy applications that target HSCs offer a great potential for the treatment of hematologic and immunologic diseases. However, the clinical success has been limited by many factors. This review is intended to summarize the recent advances made in the human HSC field, and will review the hematopoietic stem cell from definition through development to clinical applications. PMID:25457002

  8. Decontamination of radionuclides from skin: an overview.

    PubMed

    Tazrart, Anissa; Bérard, Philippe; Leiterer, Alexandra; Ménétrier, Florence

    2013-08-01

    The accident in Fukushima has emphasized the need to increase the capacity of health protection for exposed workers, first responders, and the general public in a major accident situation with release of radioactivity. Skin contamination is one of the most probable risks following major nuclear or radiological incidents, but this risk also exists and incidents can happen in industry, research laboratories, or in nuclear medicine departments. The aim of this paper is to provide an overview of the products currently used after skin contamination in order to highlight the needs and ways to improve the medical management of victims. From this review, it can be observed that the current use of these radiological decontamination products is essentially based on empiricism. In addition, some of these products are harsh and irritating, even toxic, possibly damaging the skin barrier. In some emergency situations in which clean water is in short supply, most of the current products cannot be used. Research on the mechanisms of action of decontaminating products is needed to develop a decontamination strategy. PMID:23799505

  9. Chemistry without borders: An overview

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As chemistry becomes more globalized, it is important for an organization to be interconnected and adaptable, and for an individual to keep up with changes and latest scientific findings and keep options open. Many of the challenges and the opportunities of globalization are in the areas of jobs, re...

  10. Theatre for Development: An Overview.

    ERIC Educational Resources Information Center

    Nogueira, Marcia Pompeo

    2002-01-01

    Discusses the term Theatre for Development (TFD) by addressing the theatre practice developed by a group of women in Mundemba Sub-Division, Cameroon, which was presented in Anne Tanyi-Tang's article "Theatre for Change: An Analysis of Two Performances by Women in Mundemba Sub-Division" in an earlier issue of this journal. Considers theatre as…

  11. Auditory Processing Disorders: An Overview. ERIC Digest.

    ERIC Educational Resources Information Center

    Ciocci, Sandra R.

    This digest presents an overview of children with auditory processing disorders (APDs), children who can typically hear information but have difficulty attending to, storing, locating, retrieving, and/or clarifying that information to make it useful for academic and social purposes. The digest begins by describing central auditory processing and…

  12. Early Childhood Music Education Research: An Overview

    ERIC Educational Resources Information Center

    Young, Susan

    2016-01-01

    This article offers a short commentary on the "state of play" in early childhood music education research to accompany the articles published in this special issue. It provides an international overview of recent research trends in this field, with examples drawn from Europe, the Americas, Asia, the Middle East, East and South Africa and…

  13. Regulations which require employee training: An overview

    SciTech Connect

    Gilfus, L.J.

    1995-11-01

    In order to identify the Occupational Safety and Health Administration (OSHA) regulations which apply to a certain plant or facility, one needs to find the reference materials that are needed and that can be trusted. An overview is presented of the following: Title 29 -- Labor, OSHA Training Requirements; Title 40, Environmental Protection Agency Training Requirements; and Title 49, Department of Transportation Training Regulations.

  14. Brain Research and Education: An Overview.

    ERIC Educational Resources Information Center

    Hill, Kenneth L.

    An overview of some educational implications of brain related research indicates that new insights can be gained from brain research. Four areas of study appear to be promising. First, the study of the evolution of the brain involves theories derived mostly from sociobiology, which is the study of the social behavior of animals, including humans…

  15. Observing System Simulation Experiments: An Overview

    NASA Technical Reports Server (NTRS)

    Prive, Nikki C.; Errico, Ronald M.

    2016-01-01

    An overview of Observing System Simulation Experiments (OSSEs) will be given, with focus on calibration and validation of OSSE frameworks. Pitfalls and practice will be discussed, including observation error characteristics, incestuousness, and experimental design. The potential use of OSSEs for investigation of the behaviour of data assimilation systems will be explored, including some results from experiments using the NASAGMAO OSSE.

  16. Imaging Techniques in Endodontics: An Overview

    PubMed Central

    Deepak, B. S.; Subash, T. S.; Narmatha, V. J.; Anamika, T.; Snehil, T. K.; Nandini, D. B.

    2012-01-01

    This review provides an overview of the relevance of imaging techniques such as, computed tomography, cone beam computed tomography, and ultrasound, to endodontic practice. Many limitations of the conventional radiographic techniques have been overcome by the newer methods. Advantages and disadvantages of various imaging techniques in endodontic practice are also discussed. PMID:22530184

  17. Youth Suicidal Behavior: An Introduction and Overview

    ERIC Educational Resources Information Center

    Miller, David N.; Eckert, Tanya L.

    2009-01-01

    Youth suicidal behavior continues to be a significant national problem in need of urgent attention by school personnel. The purpose of this introductory article to the special series is to provide an overview of youth suicidal behavior, including research-based information on demographic data; risk factors and warning signs; and where, when, and…

  18. Creating Smart-er Cities: An Overview

    ERIC Educational Resources Information Center

    Allwinkle, Sam; Cruickshank, Peter

    2011-01-01

    The following offers an overview of what it means for cities to be "smart." It draws the supporting definitions and critical insights into smart cities from a series of papers presented at the 2009 Trans-national Conference on Creating Smart(er) Cities. What the papers all have in common is their desire to overcome the all too often…

  19. An overview of photovoltaic applications in space

    NASA Technical Reports Server (NTRS)

    Wasel, Robert A.

    1987-01-01

    An overview is given of the uses of photovoltaic (PV) power in space. The contribution of PV systems on unmanned, low Earth orbit and inner planetary missions is noted. The development of PV technology along the two paths of high efficiency and high power is discussed. The importance of increasing the service life of PV systems is covered.

  20. An Overview of Canadian Education. Fourth Edition.

    ERIC Educational Resources Information Center

    Gayfer, Margaret

    An overview of Canadian education is provided in this book. Chapter 1 presents basic facts and figures on the educational system's general structure and diversity and the role of the federal government. The second chapter describes provincial/territorial structure, specifically: the role of the departments of education and school board, financing,…

  1. Calibration of sound calibrators: an overview

    NASA Astrophysics Data System (ADS)

    Milhomem, T. A. B.; Soares, Z. M. D.

    2016-07-01

    This paper presents an overview of calibration of sound calibrators. Initially, traditional calibration methods are presented. Following, the international standard IEC 60942 is discussed emphasizing parameters, target measurement uncertainty and criteria for conformance to the requirements of the standard. Last, Regional Metrology Organizations comparisons are summarized.

  2. NEMS - National Energy Modeling System: An Overview

    EIA Publications

    2009-01-01

    The National Energy Modeling System: An Overview 2009 a summary description of NEMS and each of its components. NEMS is a computer-based, energy-economy modeling system of energy markets for the midterm period through 2030. The NEMS is used to produce the Annual Energy Outlook.

  3. Students with Attention Deficit Disorders: An Overview.

    ERIC Educational Resources Information Center

    Salend, Spencer J.; Rohena, Elba

    2003-01-01

    This article provides the American Psychiatric Association's definition of attention deficit disorder (ADD) and then gives an overview of ADD by considering the three types of ADD, the developmental impact of ADD, factors contributing to ADD, identification and assessment of students with ADD (emphasizing multimethod and consideration of…

  4. Victims of Peer Abuse: An Overview.

    ERIC Educational Resources Information Center

    Hodges, Ernest V. E.; Perry, David G.

    1996-01-01

    Provides an overview of recent research concerning children who are habitually abused by peers. Reviews three sets of influences on victimization: (1) family factors, such as family relations that impede a child's autonomy; (2) behavioral attributes of the child, such as submissiveness; and (3) social risk factors, such as the absence of…

  5. Some results gained from JAPE: An overview

    NASA Technical Reports Server (NTRS)

    Becker, Gunnar R.

    1993-01-01

    During JAPE, a variety of sound propagation experiments were conducted including long range measurements and investigations of the masking of sound by natural barriers. An overview of the measurements is given. A comparison between measured SPL's and theoretical estimates is presented.

  6. Input, Interaction and Output: An Overview

    ERIC Educational Resources Information Center

    Gass, Susan; Mackey, Alison

    2006-01-01

    This paper presents an overview of what has come to be known as the "Interaction Hypothesis," the basic tenet of which is that through input and interaction with interlocutors, language learners have opportunities to notice differences between their own formulations of the target language and the language of their conversational…

  7. Assessment and Learning Technologies: An Overview

    ERIC Educational Resources Information Center

    Farrell, Treasa; Rushby, Nick

    2016-01-01

    Assessment pervades the learning process. This paper provides an overview of the application of technology to support and enhance diagnostic, formative and summative assessment. The focus is on examining how it can replace what already exists, improve the functionality, catalyse a redesign of the process and in some circumstances, make possible…

  8. Working Memory and Language: An Overview.

    ERIC Educational Resources Information Center

    Baddeley, Alan

    2003-01-01

    This article introduces the concept of a multi-component working memory. Emphasis is placed on the phonological loop component, its fractionation into a storage and processing component, and implications for native and second language learning. An overview of the visual spatial sketchpad and its possible role in language is provided. (Contains…

  9. The Employability Inventory: An Overview.

    ERIC Educational Resources Information Center

    Wilson, Michael J.; And Others

    1987-01-01

    Summarizes the background, development, content, and validation of the Employability Inventory, an instrument designed to assess knowledge of job seeking, job retention, and job success. Discusses usefulness of the inventory in both counseling and education. (ABL)

  10. Overview.

    ERIC Educational Resources Information Center

    Kain, Craig D.; And Others

    This document consists of the first section of a book written to educate and inform those in the helping professions on how to deal with Acquired Immune Deficiency Syndrome (AIDS). The two chapters in this first section present an overview of the AIDS crisis and provide a foundation for the rest of the book. "Emerging Trends: AIDS Today and in the…

  11. MARKAL-MACRO: An overview

    SciTech Connect

    Hamilton, L.D.; Goldstein, G.A.; Lee, J.; Marcuse, W.; Morris, S.C. ); Manne, A.S. ); Wene, C.O. Chalmers Univ. of Technology, Goeteborg )

    1992-11-12

    MARKAL-MACRO is an experiment in model linkage. This new tool is intended as an improvement over existing methods for energy policy assessment. It is designed specifically for estimating the costs and analyzing alternative technologies and policies proposed for reducing environmental risks such as global climate change or regional air pollution. The greenhouse gas debate illustrates the usefulness of linked energy-economy models. A central issue is the coupling between economic growth, the level of energy demands, and the evolution of an energy system to supply these demands. The debate is often connected with alternative modeling approaches. The competing philosophies may be labeled [open quotes]top-down macroeconomic[close quotes] and [open quotes]bottom-up engineering[close quotes] perspectives. Do macroeconomic models, with their descriptions of effects within the total economy but few technical details on the energy system, tend to overestimate future energy demands Conversely, do engineering models, ignoring feedbacks to the general economy and non-technical market factors but containing rich descriptions of technology options, tend to take too optimistic a view of conservation and the use of renewable energy sources Or is the principal difference that the engineering models ignore new sources of energy demands, and that the macroeconomic models ignore saturation effects for old categories of demands An efficient modeling tool must have the scope and detail to match the width and depth of the policy problem being analyzed. In order to respond to major environmental risks (e.g., the possibility of global climate changes), there must be long-range, fundamental changes in the energy system. For an analysis of these changes and an understanding of their nature, the modeling tool must be able to capture the complex network of relations within the energy system, as well as the opportunities of new or improved technologies.

  12. MARKAL-MACRO: An overview

    SciTech Connect

    Hamilton, L.D.; Goldstein, G.A.; Lee, J.; Marcuse, W.; Morris, S.C.; Manne, A.S.; Wene, C.O. |

    1992-11-12

    MARKAL-MACRO is an experiment in model linkage. This new tool is intended as an improvement over existing methods for energy policy assessment. It is designed specifically for estimating the costs and analyzing alternative technologies and policies proposed for reducing environmental risks such as global climate change or regional air pollution. The greenhouse gas debate illustrates the usefulness of linked energy-economy models. A central issue is the coupling between economic growth, the level of energy demands, and the evolution of an energy system to supply these demands. The debate is often connected with alternative modeling approaches. The competing philosophies may be labeled {open_quotes}top-down macroeconomic{close_quotes} and {open_quotes}bottom-up engineering{close_quotes} perspectives. Do macroeconomic models, with their descriptions of effects within the total economy but few technical details on the energy system, tend to overestimate future energy demands? Conversely, do engineering models, ignoring feedbacks to the general economy and non-technical market factors but containing rich descriptions of technology options, tend to take too optimistic a view of conservation and the use of renewable energy sources? Or is the principal difference that the engineering models ignore new sources of energy demands, and that the macroeconomic models ignore saturation effects for old categories of demands? An efficient modeling tool must have the scope and detail to match the width and depth of the policy problem being analyzed. In order to respond to major environmental risks (e.g., the possibility of global climate changes), there must be long-range, fundamental changes in the energy system. For an analysis of these changes and an understanding of their nature, the modeling tool must be able to capture the complex network of relations within the energy system, as well as the opportunities of new or improved technologies.

  13. An Overview of Down Syndrome.

    ERIC Educational Resources Information Center

    Pueschel, Siegfried M.

    This booklet presents information regarding the history, incidence, and effects of Down Syndrome. The first chapter, presenting an historical perspective of the condition, provides information on counseling parents of Down Syndrome children, and the chromosome structures seen in Down Syndrome patients. The next chapter discusses medical aspects in…

  14. Adolescent Decision Making: An Overview

    ERIC Educational Resources Information Center

    Halpern-Felsher, Bonnie

    2009-01-01

    An important developmental task during adolescence is learning to make decisions, experiencing the related positive and negative consequences, and learning from these outcomes. However, a youth's ability to make competent decisions is sometimes called into question because adolescence is also often a time of engagement in risky behaviors. This…

  15. POREWATER TOXICITY TESTING: AN OVERVIEW

    EPA Science Inventory

    Sediments act as sinks for contaminants, where they may build up to toxic levels. Sediments containing toxic levels of contaminants pose a risk to aquatic life, human health, and wildlife. There is an overwhelming amount of evidence that demonstrates chemicals in sediments are re...

  16. New Futures School: An Overview.

    ERIC Educational Resources Information Center

    Gaston, Caroline

    New Futures School (NFS), located in Albuquerque, New Mexico, is a comprehensive program for adolescent parents. NFS is an alternative school of the Albuquerque Public Schools and is supported by a non-profit, community-based organization, New Futures, Inc. There are two departments of the NFS in-school program: the Perinatal Program, serving the…

  17. An Overview of Project CORES.

    ERIC Educational Resources Information Center

    Reynolds, Bill J.

    This paper describes the activities of Project Covert and Overt Responses to Education Simulation (CORES) designed to provide an identity for students and faculty desiring to engage in simulation-related research and development activities. Activities for investigating the use of simulation are in the directions of administrative decision making,…

  18. An overview of spin physics

    SciTech Connect

    Prescott, C.Y.

    1991-07-01

    Spin physics is playing an increasingly important role in high energy experiments and theory. This review looks at selected topics in high energy spin physics that were discussed at the 9th International Symposium on High Energy Spin Physics at Bonn in September 1990.

  19. Career Development Today: An Overview.

    ERIC Educational Resources Information Center

    Gysbers, Norman C.

    This monograph on career development begins with an examination of the antecedents of present day career initiatives. The evolution of the concepts of career and career development are reviewed and the rethinking and reformulating of these concepts that have occurred since 1900 are examined. The time period from 1900 to 1950 is reviewed as the…

  20. Job Satisfaction: An International Overview

    ERIC Educational Resources Information Center

    Thurman, J. E.

    1977-01-01

    An international comparison of job satisfaction levels strongly suggests that the idea of job satisfaction as a gauge of well-being at the workplace should be rejected, but that workers' reactions to aspects of their jobs may be meaningful. The article presents data from national surveys of managers, workers, and trade unions to explain this…

  1. An Overview of Asian Rhinoplasty.

    PubMed

    Li, Dong; An, Yang; Yang, Xin

    2016-02-01

    East Asian rhinoplasty is an expanding topic in the field of rhinoplasty. Although the main principles of various rhinoplasty techniques apply equally to the East Asian nose, East Asian rhinoplasty is unique owing to its different anatomy and ethnicity. In recent years, there have been some noteworthy developments in East Asian rhinoplasty. Traditional techniques using alloplastic implants with endonasal approach are changing due to the advent of new beauty concept, introduction of new techniques, and development of newly improved materials expended polytetrafluoroethylene as an alloplastic material has gained popularity in Asian augmentation rhinoplasty. Soft expended polytetrafluoroethylene sheets as augmentation material provide promise in the future. In this review, we will highlight some of the recent advances of Asian rhinoplasty with emphasis on dorsal augmentation, advances in implant material, and tip surgery using autologous cartilage. PMID:27404467

  2. Canine mammary tumours, an overview.

    PubMed

    Sleeckx, N; de Rooster, H; Veldhuis Kroeze, E J B; Van Ginneken, C; Van Brantegem, L

    2011-12-01

    Canine mammary tumours (CMTs) are the most common neoplasms in intact female dogs. Although the prevalence of these tumours decreases in regions where preventive ovari(ohyster)ectomy is performed, it remains an important disease entity in veterinary medicine. Moreover, treatment options are limited in comparison with human breast cancer. Nevertheless, recent human treatment protocols might have potential in bitches suffering from CMTs. PMID:21645126

  3. An overview of venus geology.

    PubMed

    Saunders, R S; Arvidson, R E; Head, J W; Schaber, G G; Stofan, E R; Solomon, S C

    1991-04-12

    The Magellan spacecraft is producing comprehensive image and altimetry data for the planet Venus. Initial geologic mapping of the planet reveals a surface dominated by volcanic plains and characterized by extensive volcanism and tectonic deformation. Geologic and geomorphologic units include plains terrains, tectonic terrains, and surficial material units. Understanding the origin of these units and the relation between them is an ongoing task of the Magellan team. PMID:17769270

  4. Treating Diuretic Resistance: An Overview.

    PubMed

    Bowman, Brandi N; Nawarskas, James J; Anderson, Joe R

    2016-01-01

    Loop diuretics are central to the management of fluid overload in acute decompensated heart failure. However, a variance in the response to loop diuretics can alter a patient's clinical course and has an adverse effect on clinical outcomes. Thus, a diminished response to loop diuretics is an important clinical issue. Factors thought to contribute to diuretic resistance include erratic oral absorption in congested states and postdiuretic sodium retention. Further contributing to diuretic resistance in patients with advanced heart failure are decreases in renal perfusion and alterations in sodium handling that occur in an attempt to maintain circulatory homeostasis. Several pharmacologic interventions have been used to improve diuretic response. Intravenous diuretic administration, increasing diuretic doses, or changing diuretic agents can potentially overcome pharmacokinetic obstacles which contribute to drug resistance. Combination diuretic therapy may be useful to overcome increased sodium retention, dopamine may improve renal perfusion, and hypertonic saline may transiently increase intravascular volume and improve sodium delivery to the tubules of the nephron. Despite the prevalence of diuretic resistance, there remains a paucity of clinical trial evidence to help guide therapy in these patients. PMID:27465540

  5. Caudwell Xtreme Everest: An Overview.

    PubMed

    Grocott, Michael P W; Levett, D Z H; Martin, D S; Wilson, M H; Mackenney, A; Dhillon, S; Montgomery, H E; Mythen, M G; Mitchell, K

    2016-01-01

    The Caudwell Xtreme Everest (CXE) expedition in the spring of 2007 systematically studied 222 healthy volunteers as they ascended from sea level to Everest Base Camp (5300 m). A subgroup of climbing investigators ascended higher on Everest and obtained physiological measurements up to an altitude of 8400 m. The aim of the study was to explore inter-individual variation in response to environmental hypobaric hypoxia in order to understand better the pathophysiology of critically ill patients and other patients in whom hypoxaemia and cellular hypoxia are prevalent. This paper describes the aims, study characteristics, organization and management of the CXE expedition. PMID:27343112

  6. Australian Aboriginal Astronomy - An Overview

    NASA Astrophysics Data System (ADS)

    Norris, Ray P.; Hamacher, Duane W.

    The traditional cultures of Aboriginal Australians include a significant astronomical component, perpetuated through oral tradition, ceremony, and art. This astronomical component includes a deep understanding of the motion of objects in the sky, and this knowledge was used for practical purposes such as constructing calendars. There is also evidence that traditional Aboriginal Australians made careful records and measurements of cyclical phenomena, paid careful attention to unexpected phenomena such as eclipses and meteorite impacts, and could determine the cardinal points to an accuracy of a few degrees.

  7. Wildfire on Karst: an Overview

    NASA Astrophysics Data System (ADS)

    Coleborn, K.; Lupingna, A.; Flemons, I.; Nagra, G.; Treble, P. C.; Andersen, M. S.; Baker, A.; Tozer, M.; Fairchild, I. J.; Baker, A.; Meehan, S.

    2015-12-01

    Wildfires dramatically change the surface environment by removing vegetation and soil microbial communities and altering soil structure and geochemistry. Karst subsurface processes such as dissolution, cave formation and speleothem deposition are sensitive to environmental change, which is precisely why speleothems have been widely used as recorders of surface and climate change at an annual to millennial temporal scale. The effect of fire on karst processes is poorly understood. We hypothesise that a wildfire induced change at the surface will impact karst dissolution and precipitation processes. Firstly, sterilisation of the soil by heating causes a reduction in soil CO2 concentration which is a key component in dissolution processes. Secondly, removal of vegetation alters surface albedo and soil water storage properties. This could change the hydrology and isotopic signature of speleothem-forming drip water. We also hypothesise that a wildfire will produce a unique biogeochemical signature due to a change in the organic and inorganic properties of soil, which can be transported into speleothem forming drip water. Fire changes the organic matter character which is an important component in the mobilisation and transport of trace metals. Combustion of vegetation results in addition of ash derived minerals to the soil. Quantifying the biogeochemical signature from a burnt landscape will enable us to determine whether this wildfire signature is preserved in speleothems. This would provide the opportunity to use speleothems as recorders of fire history for the first time. Determining the impact of fire on karst processes would inform fire management and karst conservation policies.

  8. Improving vaccine uptake: An overview

    PubMed Central

    Falconer, Michelle Anne

    2013-01-01

    A task group was formed with the aim to improve the quality of the service offered by ensuring that all children waiting for an appointment for vaccination would be offered one at the earliest opportunity. Children aged between 12 mo–5 y that were not completely immunized for their age were identified and included in a pilot catch-up session. Following evaluation of the pilot session, four further immunization sessions were delivered. A total of 398 children attended the four sessions, representing an improved attendance rate of 39%. Most parents brought their children between 11am–3pm and 728 vaccines were administered: 339 MMR; 255 Pre-school boosters; 53 Hib/MenC and 81 PCV. Uptake of MMR vaccine in the PCT at age 24 mo increased by 9% by Q3 2008. For children aged five years, uptake of the first dose of MMR vaccine increased from 91.9% to 94% for the first dose and from 82.3 to 82.5% for the second dose by Q3 2008. This project demonstrates that new ways of delivering immunization sessions can be successfully implemented which can enhance access through the use of alternative venues and subsequently lead to increased vaccine uptake. PMID:23732890

  9. Trichosanthes dioica Roxb.: An overview

    PubMed Central

    Kumar, Nitin; Singh, Satyendra; Manvi; Gupta, Rajiv

    2012-01-01

    Trichosanthes, a genus of family Cucurbitaceae, is an annual or perennial herb distributed in tropical Asia and Australia. Pointed gourd (Trichosanthes dioica Roxb.) is known by a common name of parwal and is cultivated mainly as a vegetable. Juice of leaves of T. dioica is used as tonic, febrifuge, in edema, alopecia, and in subacute cases of enlargement of liver. In Charaka Samhita, leaves and fruits find mention for treating alcoholism and jaundice. A lot of pharmacological work has been scientifically carried out on various parts of T. dioica, but some other traditionally important therapeutical uses are also remaining to proof till now scientifically. According to Ayurveda, leaves of the plant are used as antipyretic, diuretic, cardiotonic, laxative, antiulcer, etc. The various chemical constituents present in T. dioica are vitamin A, vitamin C, tannins, saponins, alkaloids, mixture of noval peptides, proteins tetra and pentacyclic triterpenes, etc. PMID:22654406

  10. An overview of mammalian pluripotency.

    PubMed

    Wu, Jun; Yamauchi, Takayoshi; Izpisua Belmonte, Juan Carlos

    2016-05-15

    Mammalian pluripotency is the ability to give rise to all somatic cells as well as the germ cells of an adult mammal. It is a unique feature of embryonic epiblast cells, existing only transiently, as cells pass through early developmental stages. By contrast, pluripotency can be captured and stabilized indefinitely in cell culture and can also be reactivated in differentiated cells via nuclear reprogramming. Pluripotent stem cells (PSCs) are the in vitro carriers of pluripotency and they can inhabit discrete pluripotent states depending on the stage at which they were derived and their culture conditions. Here, and in the accompanying poster, we provide a summary of mammalian pluripotency both in vivo and in vitro, and highlight recent and future applications of PSCs for basic and translational research. PMID:27190034

  11. Obesity: overview of an epidemic.

    PubMed

    Mitchell, Nia S; Catenacci, Victoria A; Wyatt, Holly R; Hill, James O

    2011-12-01

    The obesity epidemic in the United States has proven difficult to reverse. We have not been successful in helping people sustain the eating and physical activity patterns that are needed to maintain a healthy body weight. There is growing recognition that we will not be able to sustain healthy lifestyles until we are able to address the environment and culture that currently support unhealthy lifestyles. Addressing obesity requires an understanding of energy balance. From an energy balance approach it should be easier to prevent obesity than to reverse it. Further, from an energy balance point of view, it may not be possible to solve the problem by focusing on food alone. Currently, energy requirements of much of the population may be below the level of energy intake than can reasonably be maintained over time. Many initiatives are underway to revise how we build our communities, the ways we produce and market our foods, and the ways we inadvertently promote sedentary behavior. Efforts are underway to prevent obesity in schools, worksites, and communities. It is probably too early to evaluate these efforts, but there have been no large-scale successes in preventing obesity to date. There is reason to be optimistic about dealing with obesity. We have successfully addressed many previous threats to public health. It was probably inconceivable in the 1950s to think that major public health initiatives could have such a dramatic effect on reducing the prevalence of smoking in the United States. Yet, this serious problem was addressed via a combination of strategies involving public health, economics, political advocacy, behavioral change, and environmental change. Similarly, Americans have been persuaded to use seat belts and recycle, addressing two other challenges to public health. But, there is also reason to be pessimistic. Certainly, we can learn from our previous efforts for social change, but we must realize that our challenge with obesity may be greater. In the

  12. An overview of Spacelab capabilities

    NASA Astrophysics Data System (ADS)

    Harrington, J. C.; Lohman, R. L.; Moye, J. E.

    1982-03-01

    The crew functions, instrumentation, and mission profiles for the Spacelab to be flown on board the Shuttle are described. The Spacelab will be operated by up to four scientists or engineers who are not pilots, and who are required to pass only an FAA Class III physical examination to qualify for flight. Of modular design, the Spacelab pallets can house a laboratory for human operation, or experimental pallets for control by either the ground or the Orbiter crew. A shirt sleeve environment is provided by the manned laboratory version, with the crew staying in the Orbiter mid-deck during launch and landing. Electrical power is derived from the Orbiter fuel cells, up to 12 kW for 15 min every three hours and to a total of 890 kWh. Features of the Instrument Pointing System are outlined, along with the data transmission and relay systems and the on-ground check-out facilities.

  13. Oral lichen planus: An overview

    PubMed Central

    Krupaa, R. Jayasri; Sankari, S. Leena; Masthan, K. M. K.; Rajesh, E.

    2015-01-01

    Lichen planus is an immunologically mediated mucocutaneous disease that is triggered by varied etiological agents. The oral lichenoid reaction is considered a variant of the disease that needs to be clearly diagnosed as a separate entity from oral lichen planus and treated. They follow a strict cause-effector relationship, protocols that suggest the differentiation. Lichen planus has varied clinical forms in the oral mucosa and cutaneously that has different prognosis. This condition also arises in association with various other systemic conditions such as hypertension, diabetes mellitus. There have been cases reported in the esophagus, larynx, scalp, nail, cutaneous areas, especially arms and wrists, trunk. There is reported malignant transformation that essentiates careful examination, treatment protocol and regular follow-up sessions. This article throws light on the disease condition of oral lichen planus and oral lichenoid reaction that is essential for the differentiation and treatment. PMID:26015696

  14. Federal budget process: An overview

    NASA Astrophysics Data System (ADS)

    Frizzell, Virgil A., Jr.

    Much geophysical research funding originates from the federal government, and many who obtain federal funding consider the executive branch to be its source. In fact, the federal budget results from a complex ballet between the executive and legislative branches. Because it is both little understood and essential to our work, this report will review the fundamentals of the three-year budgetary process.The Constitution assigns the power of the purse to the Congress. Before the 1920s, executive branch agencies and departments submitted their own separate budgets to Congress, and deliberate planning and priority setting was minimal. In 1921 Congress empowered the president to submit an executive branch budget reflecting his priorities for the next fiscal year. Following this protocol, former President Reagan submitted his budget for Fiscal Year 1990 in January, and President Bush outlined his FY'90 priorities in February.

  15. Trichosanthes dioica Roxb.: An overview.

    PubMed

    Kumar, Nitin; Singh, Satyendra; Manvi; Gupta, Rajiv

    2012-01-01

    Trichosanthes, a genus of family Cucurbitaceae, is an annual or perennial herb distributed in tropical Asia and Australia. Pointed gourd (Trichosanthes dioica Roxb.) is known by a common name of parwal and is cultivated mainly as a vegetable. Juice of leaves of T. dioica is used as tonic, febrifuge, in edema, alopecia, and in subacute cases of enlargement of liver. In Charaka Samhita, leaves and fruits find mention for treating alcoholism and jaundice. A lot of pharmacological work has been scientifically carried out on various parts of T. dioica, but some other traditionally important therapeutical uses are also remaining to proof till now scientifically. According to Ayurveda, leaves of the plant are used as antipyretic, diuretic, cardiotonic, laxative, antiulcer, etc. The various chemical constituents present in T. dioica are vitamin A, vitamin C, tannins, saponins, alkaloids, mixture of noval peptides, proteins tetra and pentacyclic triterpenes, etc. PMID:22654406

  16. Natural head position: An overview

    PubMed Central

    Meiyappan, N.; Tamizharasi, S.; Senthilkumar, K. P.; Janardhanan, K.

    2015-01-01

    Cephalometrics has given us a different perspective of interpreting various skeletal problems in the dentofacial complex. Natural head position (NHP) is a reproducible, physiologically determined aspect of function. To determine NHP, a horizontal or vertical reference line outside the crania was used, but preference was given generally to the horizontal. Various intra and extracranial cephalometric horizontal reference planes have been used to formulate diagnosis and plan individualized treatment for an integrated correction of the malocclusion cephalometrics is constantly undergoing refinements in its techniques and analyses to improve the clinical applications. Even though various methods for establishing NHP have been proposed, still it remains a challenge to the clinicians to implement the concept of NHP thoroughly in all the stages of treatment because of practical difficulties in the clinical scenario. PMID:26538891

  17. Ionic liquids--an overview.

    PubMed

    Jenkins, Harry Donald Brooke

    2011-01-01

    A virtually unprecedented exponential burst of activity resulted following the publication, in 1998, of an article by Michael Freeman (Freemantle, M. Chemical & Engineering News, 1998, March 30, 32), which speculated on the role and contribution that ionic liquids (ILs) might make in the future on the development of clean technology. Up until that time only a handful of researchers were routinely engaged in the study of ILs but frenzied activity followed that continues until the present day. Scientists from all disciplines related to Chemistry have now embarked on studies, including theoreticians who are immersed in the aim of improving the "designer role" so that they can tailor ILs to deliver specified properties. This article, whilst not in any sense attempting to be exhaustive, highlights the main features which characterise ILs, presenting these in a form readily assimilated by newcomers to this area of research. An extensive glossary is featured in this article as well as a chronological list which charts the major areas of development. What follows consists of a number of sections briefly describing the role of lLs as solvents, hypergolic fuels, their use in some electrochemical devices such as solar cells and lithium batteries and their use in polymerisation reactions, followed by a concise summary of some of the other roles that they are capable of playing. The role of empirical, volume-based thermodynamics procedures, as well as large scale computational studies on ILs is also highlighted. These developments which are described are remarkable in that they have been achieved in less than a decade and a half although knowledge of these materials has existed for much longer. PMID:22026149

  18. Mechanisms of karyotype differentiation in Cassidinae sensu lato (Coleoptera, Polyphaga, Chrysomelidae) based on seven species of the Brazilian fauna and an overview of the cytogenetic data.

    PubMed

    de Julio, Milena; Fernandes, Flávia Rodrigues; Costa, Cleide; Almeida, Mara Cristina; Cella, Doralice Maria

    2010-01-01

    Among the subfamilies of Chrysomelidae, Cassidinae sensu lato (s.l.) includes 6000 species distributed in 43 tribes. Approximately 100 of these species were cytogenetically analyzed and most of them presented 2n=18=16+Xy(p), which was smaller than 2n=20=18+Xy(p) considered basal for Polyphaga. However, some groups of species presented maintenance of the basal diploid number and others showed increase in this number. Certain species of the latter group also exhibited variation in the type of sex chromosome system (SCS). Considering the recent taxonomic revision accomplished for the Cassidinae s.l. species, the existence of phylogenetic relationship for some species of this subfamily, the high diversity of species of this group in the Neotropical region, and the low number of Cassidinae s.l. species karyotyped so far, the aim of the present work was to establish the main mechanisms involved in the karyotype evolution of this subfamily through the study of seven species of the Brazilian fauna and overview of the cytogenetic data. The individuals were collected in southeast and south of Brazil. The chromosomal preparations obtained from embryo and testes of adult males were stained with Giemsa solution. The species Agroiconota inedita (2n=42=40+Xy(p)), Charidotella (s.str.) immaculata (2n=22=20+Xy(p)), Charidotella (s.str.) sexpunctata (2n=22=20+Xy(p)), and Stolas chalybaea (2n=24=22+Xy(p)) revealed diploid number higher than that established as basal for Polyphaga and biarmed chromosomes. The karyotype of Cteisella confusa, Deloyala cruciata, and Metriona elatior showed the chromosomal formulae 2n=18=16+Xy(p) considered modal for Cassidinae s.l. and biarmed chromosomes. The seven species exhibited easily identified sex chromosomes due to their size and/or morphology. The analysis of meiotic cells of all the species showed pachytenes with a positively heteropycnotic block probably corresponding to the sex chromosomes; diplotenes with a high number of bivalents with two

  19. Continuous Risk Management: An Overview

    NASA Technical Reports Server (NTRS)

    Rosenberg, Linda; Hammer, Theodore F.

    1999-01-01

    Software risk management is important because it helps avoid disasters, rework, and overkill, but more importantly because it stimulates win-win situations. The objectives of software risk management are to identify, address, and eliminate software risk items before they become threats to success or major sources of rework. In general, good project managers are also good managers of risk. It makes good business sense for all software development projects to incorporate risk management as part of project management. The Software Assurance Technology Center (SATC) at NASA GSFC has been tasked with the responsibility for developing and teaching a systems level course for risk management that provides information on how to implement risk management. The course was developed in conjunction with the Software Engineering Institute at Carnegie Mellon University, then tailored to the NASA systems community. This is an introductory tutorial to continuous risk management based on this course. The rational for continuous risk management and how it is incorporated into project management are discussed. The risk management structure of six functions is discussed in sufficient depth for managers to understand what is involved in risk management and how it is implemented. These functions include: (1) Identify the risks in a specific format; (2) Analyze the risk probability, impact/severity, and timeframe; (3) Plan the approach; (4) Track the risk through data compilation and analysis; (5) Control and monitor the risk; (6) Communicate and document the process and decisions.

  20. The instructional media: an overview.

    PubMed

    Koch, H B

    1975-01-01

    The advantages of using audiovisual instructional techniques in training programs for nurses were noted and administrative strategies for encouraging the effective use of educational technology were provided. Audiovisual instructional techniques can enhance classroom learning, create opportunity for individualized learning programs, and can serve as an effective tool for monitoring and supervising clinical training. In the classroom situation, audiovisual techniques should be incorporated as a basic instructional tool and not simply used to occasionally supplement traditional learning techniques. The use of these tools can free the teacher for more personalized teaching tasks. Educational technology permits instructors to develop individualized learning programs for their students. Students can progress at their own pace and students can learn to manage their own learning process. Audiovisual tools can be used to monitor student-patient interactions. Supervisors can monitor the work of a larger number of students with these devices. These devices also permit students to reexamine and to judge their own performance. Administrations should not view educational technology as a way to reduce costs. Costs will not decline and may, at least initially, increase. Administrators should purchase equipment to fit the needs of the faculty and the students instead of expecting the faculty to develop programs suited to particular types of equipment. The faculty should be provided with assistance to learn how to operate the new equipment. PMID:45869

  1. Anogenital Pruritus – An Overview

    PubMed Central

    2016-01-01

    Anogenital pruritus is defined as intense itching, acute or chronic, affecting the anal, perianal, perineal and genital skin, which is a dominant problem in the course of various cutaneous and systemic conditions. It is one of the common, extremely annoying symptom for which patients attend the Dermatology Outpatient Department (OPD). Anogenital skin is highly sensitive to soaps, perfumes, clothing and superficial trauma and it is more prone for itchy dermatoses as a result of warmth, friction, lack of aeration, sweating and occlusive inner garments. Anogenital pruritus is associated with a wide spectrum of diseases which includes localized infections, infestations, inflammatory dermatoses, allergic and irritant conditions, anorectal diseases, systemic causes, nutritional disorders, psychological and when the cause cannot be found out it is often termed idiopathic. Patients are highly reluctant in consulting the physician for anogenital itch in the early stage, they usually present at a later stage with either atypical manifestations or depigmentation and lichenification, secondary to constant scratching. They often resort to over the counter topical agents, particularly combination products which contain topical steroids. The irrational use of such products results in complications like skin atrophy, striae, incognito etc. A proper clinical history, clinical examination, investigations like scrapping for fungus and itch mite, skin biopsy, patch test and relevant blood investigations to rule out systemic conditions should be carried out, when needed, to arrive at an accurate diagnosis, before treating the patient. PMID:27190932

  2. An Overview of Sarcopenic Obesity.

    PubMed

    Cauley, Jane A

    2015-01-01

    Sarcopenic obesity (SO) refers to the copresence of sarcopenia and obesity. In this condition, a disproportion exists between the amount of lean mass relative to fat mass. Research on SO is important because the presence of both sarcopenia and obesity may have important health consequences. However, SO research has been hampered by the disparate number of definitions of SO. Various definitions of sarcopenia include ratios of appendicular mass to height(2) or body weight, measures of muscle strength, or physical function. More recent definitions incorporate all 3. Obesity is usually defined by high body mass index, but some studies have relied on percent body fat or visceral fat. Depending on the definition, the prevalence of SO ranges from 0% to 41% in older populations. The loss of lean mass and increase in fat mass with advancing age may share common etiologic pathways. Declines in physical activity can lead to poor muscle strength, lower muscle mass, and increased fat infiltration; all of which could lead to increases in fat mass. The increases in fat mass and accompanying increases in adipokines and inflammation may further adversely affect muscle quality. SO has been related to an increased risk of mobility disability, above and beyond sarcopenia, or obesity alone. Additional research is needed to further our understanding of the pathophysiology of SO and its consequences. Interventions aimed at reducing SO may improve physical function as well as reduce disability and death. PMID:26141163

  3. Pseudoangiomatous stromal hyperplasia: an overview.

    PubMed

    Virk, Renu K; Khan, Ashraf

    2010-07-01

    Pseudoangiomatous stromal hyperplasia (PASH) of the breast is a benign, proliferative mesenchymal lesion with possible hormonal etiology. It typically affects women in the reproductive age group. Pseudoangiomatous stromal hyperplasia is frequently an incidental histologic finding in breast biopsies performed for other benign or malignant lesions. Rarely, it can present as a firm, painless breast mass, which has been referred to as nodular or tumorous PASH. Grossly, tumorous PASH is a well-circumscribed, firm, rubbery mass with solid, homogenous, gray-white cut surface. On histologic examination, it is characterized by the presence of open slitlike spaces in dense collagenous stroma. The spaces are lined by a discontinuous layer of flat, spindle-shaped myofibroblasts with bland nuclei. The spindle cells express progesterone receptors and are positive for vimentin, actin, and CD34. The most important differential diagnosis on histopathology is angiosarcoma. Pseudoangiomatous stromal hyperplasia discovered incidentally does not require any additional specific treatment. Tumorous PASH is treated by local surgical excision with clear margins and the prognosis is excellent, with minimal risk of recurrence after adequate surgical excision. PMID:20586640

  4. An overview of correctional psychiatry.

    PubMed

    Metzner, Jeffrey; Dvoskin, Joel

    2006-09-01

    Supermax facilities may be an unfortunate and unpleasant necessity in modern corrections. Because of the serious dangers posed by prison gangs, they are unlikely to disappear completely from the correctional landscape any time soon. But such units should be carefully reserved for those inmates who pose the most serious danger to the prison environment. Further, the constitutional duty to provide medical and mental health care does not end at the supermax door. There is a great deal of common ground between the opponents of such environments and those who view them as a necessity. No one should want these expensive beds to be used for people who could be more therapeutically and safely managed in mental health treatment environments. No one should want people with serious mental illnesses to be punished for their symptoms. Finally, no one wants these units to make people more, instead of less, dangerous. It is in everyone's interests to learn as much as possible about the potential of these units for good and for harm. Corrections is a profession, and professions base their practices on data. If we are to avoid the most egregious and harmful effects of supermax confinement, we need to understand them far better than we currently do. Though there is a role for advocacy from those supporting or opposed to such environments, there is also a need for objective, scientifically rigorous study of these units and the people who live there. PMID:16904510

  5. Food nanotechnology – an overview

    PubMed Central

    Sekhon, Bhupinder S

    2010-01-01

    Food nanotechnology is an area of emerging interest and opens up a whole universe of new possibilities for the food industry. The basic categories of nanotechnology applications and functionalities currently in the development of food packaging include: the improvement of plastic materials barriers, the incorporation of active components that can deliver functional attributes beyond those of conventional active packaging, and the sensing and signaling of relevant information. Nano food packaging materials may extend food life, improve food safety, alert consumers that food is contaminated or spoiled, repair tears in packaging, and even release preservatives to extend the life of the food in the package. Nanotechnology applications in the food industry can be utilized to detect bacteria in packaging, or produce stronger flavors and color quality, and safety by increasing the barrier properties. Nanotechnology holds great promise to provide benefits not just within food products but also around food products. In fact, nanotechnology introduces new chances for innovation in the food industry at immense speed, but uncertainty and health concerns are also emerging. EU/WE/global legislation for the regulation of nanotechnology in food are meager. Moreover, current legislation appears unsuitable to nanotechnology specificity. PMID:24198465

  6. Telemedicine and burns: an overview

    PubMed Central

    Atiyeh, B.; Dibo, S.A.; Janom, H.H..

    2014-01-01

    Summary Access to specialized burn care is becoming more difficult and is being restricted by the decreasing number of specialized burn centers. It is also limited by distance and resources for many patients, particularly those living in poverty or in rural medically underserved communities. Telemedicine is a rapidly evolving technology related to the practice of medicine at a distance through rapid access to remote medical expertise by telecommunication and information technologies. Feasibility of telemedicine in burn care has been demonstrated by various centers. Its use facilitates the delivery of care to patients with burn injuries of all sizes. It allows delivery of acute care and can be appropriately used for a substantial portion of the long-term management of patients after a burn by guiding less-experienced surgeons to treat and follow-up patients more appropriately. Most importantly, it allows better effective triage which reduces unnecessary time and resource demanding referrals that might overwhelm system capacities. However, there are still numerous barriers to the implementation of telemedicine, including technical difficulties, legal uncertainties, limited financial support, reimbursement issues, and an inadequate evidence base of its value and efficiency. PMID:26170782

  7. Crystallography without Crystals: An Overview

    NASA Astrophysics Data System (ADS)

    Ourmazd, Abbas

    2007-03-01

    Protein X-ray crystallography, an ``outgrowth of physics,'' is now the mainstay of biology, biochemistry, and the pharmaceutical industry. However, roughly 40% of biological molecules do not crystallize. And although more than half a million proteins have been sequenced, the structure of less than 40,000 has been determined. By obviating the need for purification and crystallization, the ability to determine the structure of individual biological molecules would constitute a fundamental breakthrough. The confluence of four developments has generated intense interest in achieving this by short-pulse X-ray scattering: *The advent of algorithms capable of ``solving the phase problem'' with practical demonstrations in astronomy, high-energy electron diffraction, and protein crystallography [1,2,3]. *Development of sophisticated techniques for determining the relative orientation of electron microscope images of biological entities such as cells and large macromolecules [4]. *Development of techniques for producing beams of hydrated proteins [3,5]. *The promise of ultra-bright, short pulses of X-rays from X-ray Free Electron Lasers (XFELs) under construction in the US, Europe, and Japan. I will describe how these and other key developments have brought the prospect of single-molecule structure determination ``tantalizingly close,'' perhaps even closer than generally realized in the literature. [1] J. R. Fienup, Appl. Opt. 21, 2758 (1982). [2] J. Miao et al. PNAS 98, 6641 (2001). [3] J.C.H. Spence et al. Acta Cryst. A61, 237 (2005) [4] J. Frank, Three-Dimensional Electron Microscopy of Macromolecular Assemblies (OUP Press, 2006) [5] J.B. Fenn, J. Biomolecular Techniques 13, 101 (2002).

  8. An overview of FTU results

    NASA Astrophysics Data System (ADS)

    Buratti, P.; Alessi, E.; Amicucci, L.; Angelini, B.; Apicella, M. L.; Apruzzese, G.; Artaserse, G.; Barbato, E.; Belli, F.; Bertocchi, A.; Bin, W.; Boncagni, L.; Botrugno, A.; Briguglio, S.; Bruschi, A.; Calabrò, G.; Cardinali, A.; Castaldo, C.; Ceccuzzi, S.; Centioli, C.; Cesario, R.; Cianfarani, C.; Cirant, S.; Crisanti, F.; D'Arcangelo, O.; De Angeli, M.; De Angelis, R.; Di Matteo, L.; Di Troia, C.; Esposito, B.; Farina, D.; Figini, L.; Fogaccia, G.; Frigione, D.; Fusco, V.; Gabellieri, L.; Galperti, C.; Garavaglia, S.; Giovannozzi, E.; Granucci, G.; Grossetti, G.; Grosso, G.; Guimarães-Filho, Z. O.; Iannone, F.; Krivska, A.; Kroegler, H.; Lazzaro, E.; Lontano, M.; Maddaluno, G.; Marchetto, C.; Marinucci, M.; Marocco, D.; Mazzitelli, G.; Mazzotta, C.; Milovanov, A.; Minelli, D.; Mirizzi, F. C.; Moro, G. A.; Napoli, F.; Nowak, S.; Orsitto, F. P.; Pacella, D.; Panaccione, L.; Panella, M.; Pericoli-Ridolfini, V.; Podda, S.; Pizzuto, A.; Pucella, G.; Ramogida, G.; Ravera, G.; Romano, A.; Sozzi, C.; Tuccillo, A. A.; Tudisco, O.; Viola, B.; Vitale, V.; Vlad, G.; Zanza, V.; Zerbini, M.; Zonca, F.; Aquilini, M.; Cefali, P.; Di Ferdinando, E.; Di Giovenale, S.; Giacomi, G.; Gravanti, F.; Grosso, A.; Mellera, V.; Mezzacappa, M.; Pensa, A.; Petrolini, P.; Piergotti, V.; Raspante, B.; Rocchi, G.; Sibio, A.; Tilia, B.; Torelli, C.; Tulli, R.; Vellucci, M.; Zannetti, D.

    2013-10-01

    Since the 2010 IAEA-FEC Conference, FTU has exploited improvements in cleaning procedures and in the density control system to complete a systematic exploration of access to high-density conditions in a wide range of plasma currents and magnetic fields. The line-averaged densities at the disruptive limit increased more than linearly with the toroidal field, while no dependence on plasma current was found; in fact, the maximum density of 4.3 × 1020 m-3 was reached at B = 8 T even at the minimum current of 0.5 MA, corresponding to twice the Greenwald limit. The lack of plasma current dependence was due to the increase in density peaking with the safety factor. Experiments with the 140 GHz electron cyclotron resonance heating (ECRH) system were focused on the sawtooth (ST) period control and on the commissioning of a new launcher with real-time steering capability that will act as the front-end actuator of a real-time system for ST period control and tearing mode stabilization. Various ECRH and electron cyclotron current-drive modulation schemes were used; with the fastest one, the ST period synchronized with an 8 ms modulation period. The observed period variations were simulated using the JETTO code with a critical shear model for the crash trigger. The new launcher was of the plug-in type, allowing quick insertion and connection to the transmission line. Both beam characteristics and steering speed were in line with design expectation. Experimental results on the connection between improved coupling of lower hybrid waves in high-density plasmas and reduced wave spectral broadening were interpreted by fully kinetic, non-linear model calculations. A dual-frequency, time-of-flight diagnostic for the measurement of density profiles was developed and successfully tested. Fishbone-like instabilities driven by energetic electrons were simulated by the hybrid MHD-gyrokinetic XHMGC code.

  9. Frontotemporal dementia: An updated overview

    PubMed Central

    Mohandas, E.; Rajmohan, V.

    2009-01-01

    Frontotemporal dementia (FTD) is a progressive neurodegenerative syndrome occurring between 45 and 65 years. The syndrome is also called frontotemporal lobar degeneration (FTLD). However, FTLD refers to a larger group of disorders FTD being one of its subgroups. The other subgroups of FTLD are progressive nonfluent aphasia (PFNA), and semantic dementia (SD). FTLD is characterized by atrophy of prefrontal and anterior temporal cortices. FTD occurs in 5-15% of patients with dementia and it is the third most common degenerative dementia. FTD occurs with equal frequency in both sexes. The age of onset is usually between 45 and 65 years though it may range anywhere from 21 to 81 years. The usual course is one of progressive clinicopathological deterioration with mortality within 6-8 years. Unlike Alzheimer’s disease (AD), this condition has a strong genetic basis and family history of FTD is seen in 40-50% of cases. FTD is a genetically complex disorder inherited as an autosomal dominant trait with high penetrance in majority of cases. Genetic linkage studies have revealed FTLD loci on chromosome 3p, 9, 9p, and 17q. The most prevalent genes are PGRN (progranulin) and MAPT (microtubule-associated protein tau), both located on chromosome 17q21. More than 15 different pathologies can underlie FTD and related disorders and it has four major types of pathological features: (1) microvacuolation without neuronal inclusions, (2) microvacuolation with ubiquitinated rounded intraneuronal inclusions and dystrophic neurites FTLD-ubiquitinated (FTLD-U), (3) transcortical gliosis with tau-reactive rounded intraneuronal inclusions, (4) microvacuolation and taupositive neurofibrillary tangles. Behavior changes are the most common initial symptom of FTD (62%), whereas speech and language problems are most common in NFPA (100%) and SD (58%). There are no approved drugs for the management of FTD and trials are needed to find effective agents. Non-pharmacological treatment and caregiver

  10. Environmental enteric dysfunction: An overview

    PubMed Central

    Crane, Rosie J.; Jones, Kelsey D. J.; Berkley, James A.

    2015-01-01

    Background Environmental enteric dysfunction (EED) refers to an incompletely defined syndrome of inflammation, reduced absorptive capacity, and reduced barrier function in the small intestine. It is widespread among children and adults in low- and middle-income countries. Understanding of EED and its possible consequences for health is currently limited. Objective A narrative review of the current understanding of EED: epidemiology, pathogenesis, therapies, and relevance to child health. Methods Searches for key papers and ongoing trials were conducted using PUBMED 1966–June 2014; ClinicalTrials.gov; the WHO Clinical Trials Registry; the Cochrane Library; hand searches of the references of retrieved literature; discussions with experts; and personal experience from the field. Results EED is established during infancy and is associated with poor sanitation, certain gut infections, and micronutrient deficiencies. Helicobacter pylori infection, small intestinal bacterial overgrowth (SIBO), abnormal gut microbiota, undernutrition, and toxins may all play a role. EED is usually asymptomatic, but it is important due to its association with stunting. Diagnosis is frequently by the dual sugar absorption test, although other biomarkers are emerging. EED may partly explain the reduced efficacy of oral vaccines in low- and middle-income countries and the increased risk of serious infection seen in children with undernutrition. Conclusions Despite its potentially significant impacts, it is currently unclear exactly what causes EED and how it can be treated or prevented. Ongoing trials involve nutritional supplements, water and sanitation interventions, and immunomodulators. Further research is needed to better understand this condition, which is of likely crucial importance for child health and development in low- and middle-income settings. PMID:25902619

  11. Frontotemporal dementia: An updated overview.

    PubMed

    Mohandas, E; Rajmohan, V

    2009-01-01

    Frontotemporal dementia (FTD) is a progressive neurodegenerative syndrome occurring between 45 and 65 years. The syndrome is also called frontotemporal lobar degeneration (FTLD). However, FTLD refers to a larger group of disorders FTD being one of its subgroups. The other subgroups of FTLD are progressive nonfluent aphasia (PFNA), and semantic dementia (SD). FTLD is characterized by atrophy of prefrontal and anterior temporal cortices. FTD occurs in 5-15% of patients with dementia and it is the third most common degenerative dementia. FTD occurs with equal frequency in both sexes. The age of onset is usually between 45 and 65 years though it may range anywhere from 21 to 81 years. The usual course is one of progressive clinicopathological deterioration with mortality within 6-8 years. Unlike Alzheimer's disease (AD), this condition has a strong genetic basis and family history of FTD is seen in 40-50% of cases. FTD is a genetically complex disorder inherited as an autosomal dominant trait with high penetrance in majority of cases. Genetic linkage studies have revealed FTLD loci on chromosome 3p, 9, 9p, and 17q. The most prevalent genes are PGRN (progranulin) and MAPT (microtubule-associated protein tau), both located on chromosome 17q21. More than 15 different pathologies can underlie FTD and related disorders and it has four major types of pathological features: (1) microvacuolation without neuronal inclusions, (2) microvacuolation with ubiquitinated rounded intraneuronal inclusions and dystrophic neurites FTLD-ubiquitinated (FTLD-U), (3) transcortical gliosis with tau-reactive rounded intraneuronal inclusions, (4) microvacuolation and taupositive neurofibrillary tangles. Behavior changes are the most common initial symptom of FTD (62%), whereas speech and language problems are most common in NFPA (100%) and SD (58%). There are no approved drugs for the management of FTD and trials are needed to find effective agents. Non-pharmacological treatment and caregiver

  12. The ESCOMPTE program: an overview

    NASA Astrophysics Data System (ADS)

    Cros, B.; Durand, P.; Cachier, H.; Drobinski, Ph.; Fréjafon, E.; Kottmeier, C.; Perros, P. E.; Peuch, V.-H.; Ponche, J.-L.; Robin, D.; Saı̈d, F.; Toupance, G.; Wortham, H.

    2004-01-01

    In this paper, the "Expérience sur Site pour COntraindre les Modèles de Pollution atmosphérique et de Transport d'Emissions" (ESCOMPTE) program is presented. The ESCOMPTE program is used to produce a relevant set of data for testing and evaluating regional pollution models. It includes high-resolution (in space and time) atmospheric emission inventories and field experiments, and covers an area of 120×120 km, centered over the Marseilles-Berre area in the southeast of France during Summer 2001. This region presents a high occurrence of photochemical pollution events, which result from numerous industrial and urban sources of primary pollutants. From the dynamical characteristics of the area, sea-breeze circulation and channeling effects due to terrain features highly influence the location of the pollutant plumes. ESCOMPTE will provide a highly documented framework for dynamics and chemistry studies. Campaign strategies and experimental set up are described. During the planning phase, existing modeling results helped defining the experimental design. The campaign involved surface measurement networks, remote sensing, ship-borne, balloon-borne, and airplane measurements. Mean standard meteorological parameters and turbulent fluxes, ozone, ozone precursors, photochemically active trace gases, and aerosols were measured. Five intensive observation periods (IOPs) were documented using a wide spectrum of instruments, involving aircraft (7) (one of them equipped with a Doppler lidar, the others for in situ meteorological and chemical measurements), constant volume balloons (33), ozone lidars (5), wind profilers (15 sodars and radars), Doppler scanning lidar (1), radiosonde systems (at 4 locations), instrumented ships (2). In addition to the air quality networks from environmental agencies, 15 supplementary ground stations equipped for chemistry and/or meteorology and/or surface flux measurements, were operational. All instruments were calibrated and compared during a

  13. Rio Grande rift: An overview

    NASA Astrophysics Data System (ADS)

    Olsen, Kenneth H.; Scott Baldridge, W.; Callender, Jonathan F.

    1987-11-01

    low-angle normal faulting throughout the rift region which was subsequently offset by high-angle normal faulting during the later deformational event. Volcanism of the Rio Grande rift is minor compared to some other continental rifts. Most of the volcanism is basaltic and occurred less than about 5 m.y. ago. Compositions range from alkalic to tholeiitic, with no unique spatial or temporal pattern. Magmas were probably derived from a variety of depths, indicating an unintegrated heat source with only local melting. Basaltic andesites and related calc-alkaline rocks erupted in the southern rift between about 30 and 18 m.y. ago were not uniquely related to the rifting process. Rather, the thermal pulse which generated these magmas was part of the previous, subduction-related event. Our interpretation of existing data concerning the evolution of the Rio Grande rift does not fit either simple active or passive "end-member" models. In particular, there is no compelling evidence for a major thermal event in the mantle uniquely associated with rifting. Yet heat—inherited from the immediately-preceding deformational regime—was certainly a critical factor in, and was probably a necessary condition for, rifting.

  14. Aerosol modulation transfer function: an overview

    NASA Astrophysics Data System (ADS)

    Kopeika, Norman S.

    1997-09-01

    The aerosol modulation transfer function (MTF) describes blurring deriving from light scatter caused by aerosols. Little scintillations or image dancing are involved. When overall atmospheric point spread function (PSF) is analyzed for its turbulence component deriving from angle-of-arrival fluctuations or scintillations, a significant portion of the PSF is left over. This is the aerosol component. This overview describes the basic physical mechanisms for aerosol MTF and its wavelength, weather, and time exposure dependences, as well as a comparison to turbulence MiT.

  15. An Observational Overview of Solar Flares

    NASA Technical Reports Server (NTRS)

    Fletcher, Lyndsay; Battaglia, M.; Dennis, Brian R.; Liu, W.; Milligan, R. O.; Hudson, H. S.; Krucker, S.; Phillips, K.; Bone, L.; Veronig, A.; Caspi, A.; Temmer, M.

    2011-01-01

    We present an overview of solar flares and associated phenomena, drawing upon a wide range of observational data primarily from the RHESSI era. Following an introductory discussion and overview of the status of observational capabilities, the article is split into topical sections which deal with different areas of flare phenomena (footpoints and ribbons, coronal sources, relationship to coronal mass ejections) and their interconnections. We also discuss flare soft X-ray spectroscopy and the energetics of the process. The emphasis is to describe the observations from multiple points of view, while bearing in mind the models that link them to each other and to theory. The present theoretical and observational understanding of solar flares is far from complete, so we conclude with a brief discussion of models, and a list of missing but important observations.

  16. High-performance computing — an overview

    NASA Astrophysics Data System (ADS)

    Marksteiner, Peter

    1996-08-01

    An overview of high-performance computing (HPC) is given. Different types of computer architectures used in HPC are discussed: vector supercomputers, high-performance RISC processors, various parallel computers like symmetric multiprocessors, workstation clusters, massively parallel processors. Software tools and programming techniques used in HPC are reviewed: vectorizing compilers, optimization and vector tuning, optimization for RISC processors; parallel programming techniques like shared-memory parallelism, message passing and data parallelism; and numerical libraries.

  17. Micro-Inspector Spacecraft: An Overview

    NASA Technical Reports Server (NTRS)

    Goldberg, Hannah; Mueller, Juergen; Alkalai, Leon

    2006-01-01

    JPL has developed a small(<5 kg) spacecraft capable of visual inspection of a host vehicle with support from NASA's Exploration Systems Mission Directorate (ESMD). This paper describes the multi-mission utility of the Micro-Inspector and presents an overview of the spacecraft system and subsystem designs, description of a typical inspection mission scenario, and initial hardware demonstrations of key subsystems, partially integrated with each other in a Micro-Inspector testbed at JPL.

  18. An overview of thermophotovoltaic generation of electricity

    SciTech Connect

    Coutts, T.J.

    1999-09-09

    This paper provides an overview of the developments in thermophotovoltaic (TPV) generation of electricity that have occurred relatively recently-from about 1994 to October 1998. The components considered are the semiconductor converter; the radiator; and the means of recirculating unusable, long-wavelength photons. A short account of the functions and performance of each of these components is given. Also discussed are operational systems and progress in modeling TPV systems.

  19. Natural computing for mechanical systems research: A tutorial overview

    NASA Astrophysics Data System (ADS)

    Worden, Keith; Staszewski, Wieslaw J.; Hensman, James J.

    2011-01-01

    A great many computational algorithms developed over the past half-century have been motivated or suggested by biological systems or processes, the most well-known being the artificial neural networks. These algorithms are commonly grouped together under the terms soft or natural computing. A property shared by most natural computing algorithms is that they allow exploration of, or learning from, data. This property has proved extremely valuable in the solution of many diverse problems in science and engineering. The current paper is intended as a tutorial overview of the basic theory of some of the most common methods of natural computing as they are applied in the context of mechanical systems research. The application of some of the main algorithms is illustrated using case studies. The paper also attempts to give some indication as to which of the algorithms emerging now from the machine learning community are likely to be important for mechanical systems research in the future.

  20. Lasers In Physical Evidence Examination: An Overview

    NASA Astrophysics Data System (ADS)

    Menzel, E. R.

    1987-01-01

    A recent application of fluorescence that is perhaps largely unknown outside law enforcement involves the utilization of laser excited fluorescence (LEF) in forensic science. In this overview, the focus is on LEF applicaton to development of latent fingerprints. Other areas of criminalistics, such as document examination and fiber analysis will be dealt with briefly only. To bring the technical reader, who likely has little familiarity with the fingerprint field, up to stream, a historical introduction precedes the description of current procedures for laser detection of latent fingerprints which is followed by a brief outline of current areas of research in the fingerprint area and application of lasers to other types of evidence examination. The overview concludes with an assessment of the current state and utilization growth prognosis of lasers in criminalistics.

  1. Compostability of bioplastic packaging materials: an overview.

    PubMed

    Kale, Gaurav; Kijchavengkul, Thitisilp; Auras, Rafael; Rubino, Maria; Selke, Susan E; Singh, Sher Paul

    2007-03-01

    Packaging waste accounted for 78.81 million tons or 31.6% of the total municipal solid waste (MSW) in 2003 in the USA, 56.3 million tons or 25% of the MSW in 2005 in Europe, and 3.3 million tons or 10% of the MSW in 2004 in Australia. Currently, in the USA the dominant method of packaging waste disposal is landfill, followed by recycling, incineration, and composting. Since landfill occupies valuable space and results in the generation of greenhouse gases and contaminants, recovery methods such as reuse, recycling and/or composting are encouraged as a way of reducing packaging waste disposal. Most of the common materials used in packaging (i.e., steel, aluminum, glass, paper, paperboard, plastics, and wood) can be efficiently recovered by recycling; however, if packaging materials are soiled with foods or other biological substances, physical recycling of these materials may be impractical. Therefore, composting some of these packaging materials is a promising way to reduce MSW. As biopolymers are developed and increasingly used in applications such as food, pharmaceutical, and consumer goods packaging, composting could become one of the prevailing methods for disposal of packaging waste provided that industry, governments, and consumers encourage and embrace this alternative. The main objective of this article is to provide an overview of the current situation of packaging compostability, to describe the main mechanisms that make a biopolymer compostable, to delineate the main methods to compost these biomaterials, and to explain the main standards for assessing compostability, and the current status of biopolymer labeling. Biopolymers such as polylactide and poly(hydroxybutyrate) are increasingly becoming available for use in food, medical, and consumer goods packaging applications. The main claims of these new biomaterials are that they are obtained from renewable resources and that they can be biodegraded in biological environments such as soil and compost

  2. Cerebral ischemia during surgery: an overview

    PubMed Central

    Zhou, Zhi-Bin; Meng, Lingzhong; Gelb, Adrian W; Lee, Roger; Huang, Wen-Qi

    2016-01-01

    Abstract Cerebral ischemia is the pathophysiological condition in which the oxygenated cerebral blood flow is less than what is needed to meet cerebral metabolic demand. It is one of the most debilitating complications in the perioperative period and has serious clinical sequelae. The monitoring and prevention of intraoperative cerebral ischemia are crucial because an anesthetized patient in the operating room cannot be neurologically assessed. In this paper, we provide an overview of the definition, etiology, risk factors, and prevention of cerebral ischemia during surgery.

  3. Pulmonary Disorders Complicating Pregnancy: An Overview.

    PubMed

    Leidecker, Katie; Dorman, Karen

    2016-01-01

    Awareness of pulmonary complications and the timely execution of appropriate interventions are critical to maintaining adequate oxygenation for the pregnant woman and the fetus. Clinicians have an opportunity during prenatal visits to provide women with education regarding pulmonary complications during pregnancy to promote positive maternal and fetal outcomes. The pulmonary conditions to be addressed in this article include asthma, tuberculosis, cystic fibrosis, and pneumonia. The purpose of this manuscript is to provide an overview of specific pulmonary conditions, as well as interventions related to each disorder and its impact on pregnancy. PMID:26813391

  4. Results from the BEAST experiment: an overview

    NASA Astrophysics Data System (ADS)

    Villela, T.; Beast Team

    We present the recent results of Cosmic Microwave Background (CMB) measurements obtained with the Background Emission Anisotropy Scanning Telescope (BEAST). BEAST is a 2.2 meter off-axis telescope, currently configured with an 8 element mixed Q (38-45 GHz) and Ka (25-35 GHz) focal plane and a modulating flat mirror. It was designed to operate both from high altitude balloons and from the ground. We present an overview of the recent BEAST results, including maps of CMB anisotropies, CMB power spectrum, and Galactic foreground contamination estimates.

  5. Hate crimes against gay males: an overview.

    PubMed

    Willis, Danny G

    2004-03-01

    As the United States has become more multicultural and diverse, there has been an increase in violence motivated by hate. Hate crimes against gay males are the most prevalent of the hate crimes based on sexual orientation. Hate crimes have their roots in normative, individual, and societal attitudes and ideologies that lead to intimidation, bullying, teasing, physical assault, rape, and murder. This paper provides an overview of the issues specific to hate crime assaults against gay males. Mental health nurses may find this knowledge useful in developing further nursing inquiry, education, and clinical practice related to hate crime and violence prevention. PMID:14726266

  6. Ocean Thermal Energy Conversion: An overview

    SciTech Connect

    Not Available

    1989-11-01

    Ocean thermal energy conversion, or OTEC is a technology that extracts power from the ocean's natural thermal gradient. This technology is being pursued by researchers from many nations; in the United States, OTEC research is funded by the US Department of Energy's Ocean Energy Technology program. The program's goal is to develop the technology so that industry can make a competent assessment of its potential -- either as an alternative or as a supplement to conventional energy sources. Federally funded research in components and systems will help OTEC to the threshold of commercialization. This publication provides an overview of the OTEC technology. 47 refs., 25 figs.

  7. Membrane Technologies in Wine Industry: An Overview.

    PubMed

    El Rayess, Youssef; Mietton-Peuchot, Martine

    2016-09-01

    Membrane processes are increasingly reported for various applications in wine industry such as microfiltration, electrodialysis, and reverse osmosis, but also emerging processes as bipolar electrodialysis and membrane contactor. Membrane-based processes are playing a critical role in the field of separation/purification, clarification, stabilization, concentration, and de-alcoholization of wine products. They begin to be an integral part of the winemaking process. This review will provide an overview of recent developments, applications, and published literature in membrane technologies applied in wine industry. PMID:25751507

  8. Hearing Loss in the Elderly: An Overview

    PubMed Central

    Blakley, Brian W.

    1989-01-01

    Loss of hearing is tragic, yet most of those afflicted can be helped. Surgery is sometimes appropriate, but for the majority a hearing aid is the best answer. This article reviews what happens in different hearing losses, and gives an overview of hearing aids for the physician who lacks an extensive technical background but wishes to understand these devices a little better. Simple tips for investigation of hearing-aid complaints are included, as well as some tips for communication with hard-of-hearing persons. PMID:21249000

  9. Identifying Cognitive Mechanisms Targeted for Treatment Development in Schizophrenia: An Overview of the First Meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) Initiative

    PubMed Central

    Carter, Cameron S.; Barch, Deanna M.; Buchanan, Robert W.; Bullmore, Ed; Krystal, John H.; Cohen, Jonathan; Geyer, Mark; Green, Michael; Nuechterlein, Keith H.; Robbins, Trevor; Silverstein, Steven; Smith, Edward E.; Strauss, Milton; Wykes, Til; Heinssen, Robert

    2008-01-01

    This overview describes the generation and development of the ideas that led to the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) initiative. It also describes the organization, process and products of the first meeting. The CNTRICS initiative involves a series of three conferences that will systematically address barriers to translating paradigms developed in the basic animal and human cognitive neuroscience fields for use in translational research aimed at developing novel treatments for cognitive impairments in schizophrenia. The articles in this special section report on the results of the first conference, which used a criterion based consensus-building process to develop a set of cognitive constructs to be targeted for translation efforts. PMID:18466880

  10. Superconducting Radio Frequency Technology: An Overview

    SciTech Connect

    Peter Kneisel

    2003-06-01

    Superconducting RF cavities are becoming more often the choice for larger scale particle accelerator projects such as linear colliders, energy recovery linacs, free electron lasers or storage rings. Among the many advantages compared to normal conducting copper structures, the superconducting devices dissipate less rf power, permit higher accelerating gradients in CW operation and provide better quality particle beams. In most cases these accelerating cavities are fabricated from high purity bulk niobium, which has superior superconducting properties such as critical temperature and critical magnetic field when compared to other superconducting materials. Research during the last decade has shown, that the metallurgical properties--purity, grain structure, mechanical properties and oxidation behavior--have significant influence on the performance of these accelerating devices. This contribution attempts to give a short overview of the superconducting RF technology with emphasis on the importance of the material properties of the high purity niobium.

  11. Kynurenine pathway and disease: an overview.

    PubMed

    Pérez-De La Cruz, Verónica; Königsberg, Mina; Santamaría, Abel

    2007-12-01

    Kynurenine pathway is gaining more and more attention every day in biomedical research since this catabolic route for tryptophan decomposition is not only implicated in different neurological disorders, but also possesses neuroactive metabolites with different biological properties, such as pro-oxidant and antioxidant regulators. Thus, the intensive research on this metabolic pathway is helping us to understand those mechanisms underlying neurodegenerative events during the occurrence of pathological process in the central nervous system (CNS), thereby allowing the design of potential therapies for those disorders involving excitotoxic, oxidative and inflammatory components. Here we intend to provide a brief overview on the relevance of this route for several CNS disorders, and discuss recent information on the different biological properties of the neuroactive metabolites of this pathway and their significance for further research. PMID:18220779

  12. An overview of permanent and semipermanent fillers.

    PubMed

    Broder, Kevin W; Cohen, Steven R

    2006-09-01

    The demand for safe, effective, long-lasting, biocompatible dermal filler materials is increasing. Many products that include synthetic polymers and autologous tissue have emerged that attempt to meet these criteria. An overview of injectable permanent fillers, including ArteFill, Aquamid, and silicone, and semipermanent fillers, including Radiesse, Sculptra, and autologous fat, is presented. A discussion of their composition, histologic characteristics, antigenicity, U.S. Food and Drug Administration approval status, indications for use, efficacy, injection technique, and adverse effects is provided. PMID:16936539

  13. Chandra Observations of Neutron Stars: An Overview

    NASA Technical Reports Server (NTRS)

    Weisskopf, Martin C.; Karovska, M.; Pavlov, G. G.; Zavlin, V. E.; Clarke, Tracy

    2006-01-01

    We present a brief review of Chandra X-ray Observatory observations of neutron stars. The outstanding spatial and spectral resolution of this great observatory have allowed for observations of unprecedented clarity and accuracy. Many of these observations have provided new insights into neutron star physics. We present an admittedly biased and overly brief overview of these observations, highlighting some new discoveries made possible by the Observatory's unique capabilities. We also include our analysis of recent multiwavelength observations of the putative pulsar and its pulsar-wind nebula in the IC 443 SNR.

  14. High-Energy Astrophysics: An Overview

    NASA Technical Reports Server (NTRS)

    Fishman, Gerald J.

    2007-01-01

    High-energy astrophysics is the study of objects and phenomena in space with energy densities much greater than that found in normal stars and galaxies. These include black holes, neutron stars, cosmic rays, hypernovae and gamma-ray bursts. A history and an overview of high-energy astrophysics will be presented, including a description of the objects that are observed. Observing techniques, space-borne missions in high-energy astrophysics and some recent discoveries will also be described. Several entirely new types of astronomy are being employed in high-energy astrophysics. These will be briefly described, along with some NASA missions currently under development.

  15. Retail video analytics: an overview and survey

    NASA Astrophysics Data System (ADS)

    Connell, Jonathan; Fan, Quanfu; Gabbur, Prasad; Haas, Norman; Pankanti, Sharath; Trinh, Hoang

    2013-03-01

    Today retail video analytics has gone beyond the traditional domain of security and loss prevention by providing retailers insightful business intelligence such as store traffic statistics and queue data. Such information allows for enhanced customer experience, optimized store performance, reduced operational costs, and ultimately higher profitability. This paper gives an overview of various camera-based applications in retail as well as the state-ofthe- art computer vision techniques behind them. It also presents some of the promising technical directions for exploration in retail video analytics.

  16. Computer-assisted cartography: an overview.

    USGS Publications Warehouse

    Guptill, S.C.; Starr, L.E.

    1984-01-01

    An assessment of the current status of computer-assisted cartography, in part, is biased by one's view of the cartographic process as a whole. From a traditional viewpoint we are concerned about automating the mapping process; from a progressive viewpoint we are concerned about using the tools of computer science to convey spatial information. On the surface these viewpoints appear to be in opposition. However, it is postulated that in the final analysis, they face the same goal. This overview uses the perspectives from two viewpoints to depict the current state of computer-assisted cartography and speculate on future goals, trends, and challenges.-Authors

  17. Survey of independent inventors: An overview

    SciTech Connect

    Whalley, P.

    1992-12-01

    Independent inventors are important but little-researched members of the US technical community. The survey reported on here is the first in modern times to attempt to provide a profile of the US independent inventor that goes beyond a single geographical or organizational locale. The report that follows provides an overview of the demographics, practices and concerns of the modern US inventor as represented by the members of leading US inventor organizations. It is by no means comprehensive but seeks to be indicative of the issues raised in the survey each which will be dealt with more comprehensively in future publications.

  18. Landsat 7 Science Data Processing: An Overview

    NASA Technical Reports Server (NTRS)

    Schweiss, Robert J.; Daniel, Nathaniel E.; Derrick, Deborah K.

    2000-01-01

    The Landsat 7 Science Data Processing System, developed by NASA for the Landsat 7 Project, provides the science data handling infrastructure used at the Earth Resources Observation Systems (EROS) Data Center (EDC) Landsat Data Handling Facility (DHF) of the United States Department of Interior, United States Geological Survey (USGS) located in Sioux Falls, South Dakota. This paper presents an overview of the Landsat 7 Science Data Processing System and details of the design, architecture, concept of operation, and management aspects of systems used in the processing of the Landsat 7 Science Data.

  19. Diode pumped alkali lasers (DPALs): an overview

    NASA Astrophysics Data System (ADS)

    Krupke, William F.

    2008-05-01

    The concept of power-scalable, high beam-quality diode pumped alkali lasers was introduced in 2003 [Krupke, US Patent No. 6,643,311; Opt. Letters, 28, 2336 (2003)]. Since then several laboratory DPAL devices have been reported on, confirming many of the spectroscopic, kinetic, and laser characteristics projected from literature data. This talk will present an overview of the DPAL concept, summarize key relevant properties of the cesium, rubidium, and potassium alkali vapor gain media so-far examined, outline power scaling considerations, and highlight results of published DPAL laboratory experiments.

  20. Pulmonary hypertension and pregnancy: an overview.

    PubMed

    Gei, Alfredo; Montúfar-Rueda, Carlos

    2014-12-01

    Pulmonary hypertension is a syndrome infrequently associated with pregnancy. Despite advancements in therapy during the past 25 years and encouraging reports of improved outcomes, pulmonary arterial hypertension remains a devastating disease with a significantly reduced lifespan. This disorder should still be considered a contraindication to pregnancy. The decision of a patient to continue the pregnancy should be supported by an empathetic group of health care professionals who would optimize their treatment and hopefully their pregnancy outcomes and survival after delivery. We overview here different aspects of the diagnosis, evaluation, management, and counseling of patients suffering from pulmonary hypertension during pregnancy. PMID:25314091

  1. THEORY IN RELIGION AND AGING: AN OVERVIEW

    PubMed Central

    Levin, Jeff; Chatters, Linda M.; Taylor, Robert Joseph

    2011-01-01

    This paper provides an overview of theory in religion, aging, and health. It offers both a primer on theory and a roadmap for researchers. Four “tenses” of theory are described—distinct ways that theory comes into play in this field: grand theory, mid-range theory, use of theoretical models, and positing of constructs which mediate or moderate putative religious effects. Examples are given of both explicit and implicit uses of theory. Sources of theory for this field are then identified, emphasizing perspectives of sociologists and psychologists, and discussion is given to limitations of theory. Finally, reflections are offered as to why theory matters. PMID:20087662

  2. Hippocampus in health and disease: An overview

    PubMed Central

    Anand, Kuljeet Singh; Dhikav, Vikas

    2012-01-01

    Hippocampus is a complex brain structure embedded deep into temporal lobe. It has a major role in learning and memory. It is a plastic and vulnerable structure that gets damaged by a variety of stimuli. Studies have shown that it also gets affected in a variety of neurological and psychiatric disorders. In last decade or so, lot has been learnt about conditions that affect hippocampus and produce changes ranging from molecules to morphology. Progresses in radiological delineation, electrophysiology, and histochemical characterization have made it possible to study this archicerebral structure in greater detail. Present paper attempts to give an overview of hippocampus, both in health and diseases. PMID:23349586

  3. Assessment formats in dental medicine: An overview

    PubMed Central

    Gerhard-Szep, Susanne; Güntsch, Arndt; Pospiech, Peter; Söhnel, Andreas; Scheutzel, Petra; Wassmann, Torsten; Zahn, Tugba

    2016-01-01

    Aim: At the annual meeting of German dentists in Frankfurt am Main in 2013, the Working Group for the Advancement of Dental Education (AKWLZ) initiated an interdisciplinary working group to address assessments in dental education. This paper presents an overview of the current work being done by this working group, some of whose members are also actively involved in the German Association for Medical Education's (GMA) working group for dental education. The aim is to present a summary of the current state of research on this topic for all those who participate in the design, administration and evaluation of university-specific assessments in dentistry. Method: Based on systematic literature research, the testing scenarios listed in the National Competency-based Catalogue of Learning Objectives (NKLZ) have been compiled and presented in tables according to assessment value. Results: Different assessment scenarios are described briefly in table form addressing validity (V), reliability (R), acceptance (A), cost (C), feasibility (F), and the influence on teaching and learning (EI) as presented in the current literature. Infoboxes were deliberately chosen to allow readers quick access to the information and to facilitate comparisons between the various assessment formats. Following each description is a list summarizing the uses in dental and medical education. Conclusion: This overview provides a summary of competency-based testing formats. It is meant to have a formative effect on dental and medical schools and provide support for developing workplace-based strategies in dental education for learning, teaching and testing in the future. PMID:27579365

  4. An overview of custom array sequencing.

    PubMed

    Kothiyal, Prachi; Cox, Stephanie; Ebert, Jonathan; Aronow, Bruce J; Greinwald, John H; Rehm, Heidi L

    2009-04-01

    This unit provides an overview of oligo hybridization-based resequencing and a wide range of considerations for implementing the technology and analyzing the resulting data. The specific technology discussed is the Affymetrix GeneChip CustomSeq Resequencing Array platform. Concepts related to array design, experimental protocols, and base-calling using existing algorithms are presented. Details that should be evaluated during development of sequence tiling, target amplification, and PCR protocols are addressed. An overview of the Affymetrix GeneChip Sequence Analysis Software (GSEQ) is provided, along with factors that influence base-calling coverage and accuracy. Also outlined are performance measures that can be used to characterize base-calling with resequencing arrays, as well as factors known to affect their performance. Limitations associated with detection of insertions and deletions (indels) are discussed, with empirical data from our experiments used to outline possible approaches to indel detection. Critical topics in the design, implementation, and analysis of targeted sequencing arrays not previously discussed in detail are highlighted. PMID:19360699

  5. Time scarcity and food choices: an overview.

    PubMed

    Jabs, Jennifer; Devine, Carol M

    2006-09-01

    Time scarcity, the feeling of not having enough time, has been implicated in changes in food consumption patterns such as a decrease in food preparation at home, an increase in the consumption of fast foods, a decrease in family meals, and an increase in the consumption of convenience or ready-prepared foods. These food choices are associated with less healthful diets and may contribute to obesity and chronic health problems such as cardiovascular disease, diabetes, and cancer. In spite of the potential importance for health, there has been little study of how time scarcity influences people's food choices. This paper presents an overview of time issues related to food choices and discuss applications of time research for nutrition and health researchers, policy makers, and practitioners interested in food choice. PMID:16698116

  6. An Overview of Spray-On Foam Insulation Applications on the Space Shuttle's External Tank: Foam Applications and Foam Shedding Mechanisms

    NASA Technical Reports Server (NTRS)

    Sullivan, Roy M.; Lerch, Bradley A.; Rogers, Patrick R.; Sparks, Scotty S.

    2006-01-01

    The Columbia Accident Investigation Board (CAIB) concluded that the cause of the tragic loss of the Space Shuttle Columbia and its crew was a breach in the thermal protection system on the leading edge of the left wing. The breach was initiated by a piece of insulating foam that separated from the left bipod ramp of the External Tank and struck the wing in the vicinity of the lower half of Reinforced Carbon-Carbon panel No. 8 at 81.9 seconds after launch. The CAIB conclusion has spawned numerous studies to identify the cause of and factors influencing foam shedding and foam debris liberation from the External Tank during ascent. The symposium on the Thermo-mechanics and Fracture of Space Shuttle External Tank Spray-On Foam Insulation is a collection of presentations that discuss the physics and mechanics of the ET SOFI with the objective of improving analytical and numerical methods for predicting foam thermo-mechanical and fracture behavior. This keynote presentation sets the stage for the presentations contained in this symposium by introducing the audience to the various types of SOFI applications on the Shuttle s External Tank and by discussing the various mechanisms that are believed to be the cause of foam shedding during the Shuttle s ascent to space

  7. An overview of the neuron ring model

    NASA Technical Reports Server (NTRS)

    Taber, Rod

    1991-01-01

    The Neuron Ring model employs an avalanche structure with two important distinctions at the neuron level. Each neuron has two memory latches; one traps maximum neuronal activation during pattern presentation, and the other records the time of latch content change. The latches filter short term memory. In the process, they preserve length 1 snapshots of activation theory history. The model finds utility in pattern classification. Its synaptic weights are first conditioned with sample spectra. The model then receives a test or unknown signal. The objective is to identify the sample closest to the test signal. Class decision follows complete presentation of the test data. The decision maker relies exclusively on the latch contents. Presented here is an overview of the Neuron Ring at the seminar level.

  8. Planck AN Overview of the Spacecraft

    NASA Astrophysics Data System (ADS)

    Passvogel, T.; Crone, G.; Piersanti, O.; Guillaume, B.; Tauber, J.; Reix, J.-M.; Banos, T.; Rideau, P.; Collaudin, B.

    2010-04-01

    The two science missions Herschel, an observatory-type mission, and Planck, a survey mission, are combined in one program within ESA's long-term science program. This paper deals with Planck. The objective for Planck is to image systematically the whole sky simultaneously with two scientific instruments in nine frequency channels between 30 and 900 GHz to unravel the temperature fluctuations, i.e. the anisotropy, of the cosmic background radiation. Both satellites, have been launched together from the European Space Port in Kourou, French Guiana, on a single Ariane 5 launcher, the orbits will be Lissajous orbits around the 2nd Lagrange Point, ``so called'' L2 of the Earth-Sun system. This paper gives an overview of the Planck spacecraft including the scientific instruments and the on ground testing.

  9. An overview of interstitial brachytherapy and hyperthermia

    SciTech Connect

    Brandt, B.B.; Harney, J.

    1989-11-01

    Interstitial thermoradiotherapy, an experimental cancer treatment that combines interstitial radiation implants (brachytherapy) and interstitial hyperthermia, is in the early stages of investigation. In accordance with the procedure used in a current national trial protocol, a 60-minute hyperthermia treatment is administered after catheters are placed into the tumor area while the patient is under general anesthesia. This is immediately followed by loading of radioactive Iridium-192 seeds into the catheters for a defined period of time. Once the prescribed radiation dose is delivered, the radioactive sources are removed and a second, 60-minute hyperthermia treatment is administered. Clinical trials with hyperthermia in combination with radiation have increased in recent years. Nurses caring for these patients need to become more knowledgeable about this investigational therapy. This paper provides an overview of the biologic rationale for this therapy, as well as a description of the delivery method and clinical application. Specific related nursing interventions are defined in a nursing protocol.23 references.

  10. Supersonic STOVL propulsion technology program: An overview

    NASA Technical Reports Server (NTRS)

    Blaha, Bernard J.; Batterton, Peter G.

    1987-01-01

    Planning activities are continuing between NASA, DOD, and two foreign governments to develop the technology and to demonstrate the design capability for advanced, supersonic, short-takeoff and vertical-landing (STOVL) aircraft by the mid-1990s. As a result, a Memorandum of Understanding (MOU) was established by the United Kingdom to jointly pursue the required technology; and an MOU with Canada is expected to be signed shortly. The NASA Lewis Research Center will play a lead role in the development of the required propulsion technologies which were identified as being critical to achieve viable STOVL aircraft. These planning activities have already resulted in initial research programs focused on technologies common to two or more of the proposed propulsion system concepts. An overview of the Lewis Research Center's role in the overall program plan and recent results in the development of the required propulsion technologies is presented.

  11. Conotoxins Targeting Nicotinic Acetylcholine Receptors: An Overview

    PubMed Central

    Lebbe, Eline K. M.; Peigneur, Steve; Wijesekara, Isuru; Tytgat, Jan

    2014-01-01

    Marine snails of the genus Conus are a large family of predatory gastropods with an unparalleled molecular diversity of pharmacologically active compounds in their venom. Cone snail venom comprises of a rich and diverse cocktail of peptide toxins which act on a wide variety of ion channels such as voltage-gated sodium- (NaV), potassium- (KV), and calcium- (CaV) channels as well as nicotinic acetylcholine receptors (nAChRs) which are classified as ligand-gated ion channels. The mode of action of several conotoxins has been the subject of investigation, while for many others this remains unknown. This review aims to give an overview of the knowledge we have today on the molecular pharmacology of conotoxins specifically interacting with nAChRs along with the structure–function relationship data. PMID:24857959

  12. Scrupulosity disorder: an overview and introductory analysis.

    PubMed

    Miller, Chris H; Hedges, Dawson W

    2008-08-01

    Scrupulosity is a psychological disorder primarily characterized by pathological guilt or obsession associated with moral or religious issues that is often accompanied by compulsive moral or religious observance and is highly distressing and maladaptive. This paper provides a comprehensive overview of scrupulosity and an original conceptualization of the disorder based on an exhaustive literature review to increase awareness of the disorder among practicing clinicians and stimulate further research. It explores the clinical features of scrupulosity, classified as cognitive, behavioral, affective, and social features, as well as the epidemiology, etiology, and treatment of the disorder. Additionally, it is suggested that scrupulosity, despite its similarity to OCD, may merit a distinctive diagnosis, particularly considering its unique constellation and severity of symptoms and its treatment refractoriness, as supported by statistical analysis. PMID:18226490

  13. Mobile multimedia understanding applications: an overview

    NASA Astrophysics Data System (ADS)

    Lin, Xiaofan

    2011-03-01

    In recent years, mobile devices are quickly reaching almost every corner of our daily life in a variety of forms: personal media players, smart phones, netbooks, and tablets. Besides the more powerful, smaller, and more versatile hardware, another driving force is the vast number of software applications ("apps") on those mobile devices. A number of mobile apps employ intelligent multimedia understanding (MU) technologies. This paper gives an overview of such apps. The focus is not on the underlying MU techniques, which are already covered by a huge amount of literature. Instead, it attempts to shed some light on the junction of mobile apps and MU. For this purpose, it addresses a number of important aspects: unique requirements and characteristics of MU-related apps, values brought in by MU, typical MU technologies, various system architectures, available development tools, and related standards.

  14. Fundamentals of natural computing: an overview

    NASA Astrophysics Data System (ADS)

    de Castro, Leandro Nunes

    2007-03-01

    Natural computing is a terminology introduced to encompass three classes of methods: (1) those that take inspiration from nature for the development of novel problem-solving techniques; (2) those that are based on the use of computers to synthesize natural phenomena; and (3) those that employ natural materials (e.g., molecules) to compute. The main fields of research that compose these three branches are the artificial neural networks, evolutionary algorithms, swarm intelligence, artificial immune systems, fractal geometry, artificial life, DNA computing, and quantum computing, among others. This paper provides an overview of the fundamentals of natural computing, particularly the fields listed above, emphasizing the biological motivation, some design principles, their scope of applications, current research trends and open problems. The presentation is concluded with a discussion about natural computing, and when it should be used.

  15. Complementary therapies for depression: an overview.

    PubMed

    Ernst, E; Rand, J I; Stevinson, C

    1998-11-01

    Depression is one of the most common reasons for using complementary and alternative therapies. The aim of this article is to provide an overview of the evidence available on the treatment of depression with complementary therapies. Systematic literature searches were performed using several databases, reference list searching, and inquiry to colleagues. Data extraction followed a predefined protocol. The amount of rigorous scientific data to support the efficacy of complementary therapies in the treatment of depression is extremely limited. The areas with the most evidence for beneficial effects are exercise, herbal therapy (Hypericum perforatum), and, to a lesser extent, acupuncture and relaxation therapies. There is a need for further research involving randomized controlled trials into the efficacy of complementary and alternative therapies in the treatment of depression. PMID:9819072

  16. An overview of Japanese occupational health.

    PubMed Central

    Reich, M R; Frumkin, H

    1988-01-01

    This paper provides an overview of Japanese occupational health and evaluates the current situation from three perspectives. Major occupational health hazards are assessed using four sources of data, showing patterns similar to those found in other advanced industrial societies. Institutional structures for occupational health policy are then examined, illustrating strengths and weaknesses of the Japanese legal and administrative systems. Trade union activities are presented, indicating the constraints of enterprise unions, and the tendency for a greater orientation toward compensation than prevention. Significant occupational health problems persist among marginal workers in Japan, including women and various minority groups. The analysis demonstrates a record for occupational health in Japan considerably more mixed than the conventional view. PMID:2968056

  17. Nuclear track-based biosensing: an overview

    NASA Astrophysics Data System (ADS)

    Fink, Dietmar; Muñoz Hernández, Gerardo; García Arellano, Humberto; Vacík, Jiri; Havranek, Vladimir; Hnatowicz, Vladimir; Kiv, Arik; Alfonta, Lital

    2016-02-01

    An overview on the development of biosensors based on nuclear tracks in solids is presented. A few decades ago it was found that nuclear tracks in solids can be usefully applied for the creation of biosensors. Meanwhile quite a number of different strategies have emerged to fulfill this task which are summarized here. We ourselves have especially concentrated on the 'Product Enrichment Strategy', where the enrichment of products of a given analyte by a suitable biochemical reaction within the narrow confinement of etched ion tracks is used to amplify the product's signal for high-sensitivity biosensing. We also report on the application of nuclear analysis techniques for obtaining a deeper insight into these sensor structures, for the sake of their further optimization. Last not least we also discuss competing nanopore-based biosensing approaches.

  18. Weathering of Roofing Materials-An Overview

    SciTech Connect

    Berdahl, Paul; Akbari, Hashem; Levinson, Ronnen; Miller, William A.

    2006-03-30

    An overview of several aspects of the weathering of roofing materials is presented. Degradation of materials initiated by ultraviolet radiation is discussed for plastics used in roofing, as well as wood and asphalt. Elevated temperatures accelerate many deleterious chemical reactions and hasten diffusion of material components. Effects of moisture include decay of wood, acceleration of corrosion of metals, staining of clay, and freeze-thaw damage. Soiling of roofing materials causes objectionable stains and reduces the solar reflectance of reflective materials. (Soiling of non-reflective materials can also increase solar reflectance.) Soiling can be attributed to biological growth (e.g., cyanobacteria, fungi, algae), deposits of organic and mineral particles, and to the accumulation of flyash, hydrocarbons and soot from combustion.

  19. Research on atmospheric volcanic emissions - An overview

    NASA Technical Reports Server (NTRS)

    Friend, J. P.; Bandy, A. R.; Moyers, J. L.; Zoller, W. H.; Stoiber, R. E.; Torres, A. L.; Rose, W. I., Jr.; Mccormick, M. P.; Woods, D. C.

    1982-01-01

    Atmospheric abundances and the geochemical cycle of certain volatile compounds and elements may be largely influenced or entirely controlled by magmatic sources. However, better estimates of the magnitude and variability of volcanic emissions are required if the importance of this natural source of atmospheric constituents and the resulting effect on atmospheric chemistry are to be elucidated. The project 'Research on Atmospheric Volcanic Emissions' (RAVE) is concerned with the improvement of knowledge of both geological and chemical phenomena attending these emissions by means of comprehensive instrumentation on board a research aircraft making simultaneous measurements of plume constituents. A description is presented of the equipment and the procedures used in the RAVE field study of Mt. St. Helens' plume. An overview of the results is also provided.

  20. Workforce competencies in behavioral health: an overview.

    PubMed

    Hoge, Michael A; Paris, Manuel; Adger, Hoover; Collins, Frank L; Finn, Cherry V; Fricks, Larry; Gill, Kenneth J; Haber, Judith; Hansen, Marsali; Ida, D J; Kaplan, Linda; Northey, William F; O'Connell, Maria J; Rosen, Anita L; Taintor, Zebulon; Tondora, Janis; Young, Alexander S

    2005-01-01

    Competency-based training approaches are being used more in healthcare to guide curriculum content and ensure accountability and outcomes in the educational process. This article provides an overview of the state of competency development in the field of behavioral health. Specifically, it identifies the groups and organizations that have conducted and supported this work, summarizes their progress in defining and assessing competencies, and discusses both the obstacles and future directions for such initiatives. A major purpose of this article is to provide a compendium of current competency efforts so that these might inform and enhance ongoing competency development in the varied behavioral health disciplines and specialties. These varied resources may also be useful in identifying the core competencies that are common to the multiple disciplines and specialties. PMID:16082798

  1. Supersonic STOVL propulsion technology program: An overview

    NASA Technical Reports Server (NTRS)

    Blaha, Bernard J.; Batterton, Peter G.

    1990-01-01

    Planning activities are continuing between NASA, the DoD, and two foreign governments to develop the technology and to show the design capability by the mid-1990's for advanced, supersonic, short takeoff and vertical landing (STOVL) aircraft. Propulsion technology is the key to achieving viable STOVL aircraft, and NASA Lewis will play a lead role in the development of these required propulsion technologies. The initial research programs are focused on technologies common to two or more of the possible STOVL propulsion system concepts. An overview is presented of the NASA Lewis role in the overall program plan and recent results of the research program. The future research program will be focused on one or possibly two of the propulsion concepts seen as most likely to be successful in the post advanced tactical fighter time frame.

  2. An overview of fast multipole methods

    SciTech Connect

    Strickland, J.H.; Baty, R.S.

    1995-11-01

    A number of physics problems may be cast in terms of Hilbert-Schmidt integral equations. In many cases, the integrals tend to be zero over a large portion of the domain of interest. All of the information is contained in compact regions of the domain which renders their use very attractive from the standpoint of efficient numerical computation. Discrete representation of these integrals leads to a system of N elements which have pair-wise interactions with one another. A direct solution technique requires computational effort which is O(N{sup 2}). Fast multipole methods (FMM) have been widely used in recent years to obtain solutions to these problems requiring a computational effort of only O(Nln N) or O(N). In this paper we present an overview of several variations of the fast multipole method along with examples of its use in solving a variety of physical problems.

  3. Diagnostic instruments for behavioural addiction: an overview

    PubMed Central

    Albrecht, Ulrike; Kirschner, Nina Ellen; Grüsser, Sabine M.

    2007-01-01

    In non-substance-related addiction, the so-called behavioural addiction, no external psychotropic substances are consumed. The psychotropic effect consists of the body’s own biochemical processes induced only by excessive activities. Until recently, knowledge was limited with respect to clinically relevant excessive reward-seeking behaviour, such as pathological gambling, excessive shopping and working which meet diagnostic criteria of dependent behaviour. To date, there is no consistent concept for diagnosis and treatment of excessive reward-seeking behaviour, and its classification is uncertain. Therefore, a clear conceptualization of the so-called behavioural addictions is of great importance. The use of adequate diagnostic instruments is necessary for successful therapeutical implications. This article provides an overview of the current popular diagnostic instruments assessing the different forms of behavioural addiction. Especially in certain areas there are only few valid and reliable instruments available to assess excessive rewarding behaviours that fulfill the criteria of addiction. PMID:19742294

  4. Marine Polysaccharides in Pharmaceutical Applications: An Overview

    PubMed Central

    Laurienzo, Paola

    2010-01-01

    The enormous variety of polysaccharides that can be extracted from marine plants and animal organisms or produced by marine bacteria means that the field of marine polysaccharides is constantly evolving. Recent advances in biological techniques allow high levels of polysaccharides of interest to be produced in vitro. Biotechnology is a powerful tool to obtain polysaccharides from a variety of micro-organisms, by controlling the growth conditions in a bioreactor while tailoring the production of biologically active compounds. Following an overview of the current knowledge on marine polysaccharides, with special attention to potential pharmaceutical applications and to more recent progress on the discovering of new polysaccharides with biological appealing characteristics, this review will focus on possible strategies for chemical or physical modification aimed to tailor the final properties of interest. PMID:20948899

  5. The hospital sector in Germany: an overview.

    PubMed

    Schölkopf, M

    2000-01-01

    The German health care system has recently experienced far reaching reforms within its hospital sector, including a new financing and remuneration system, the life span of which is to the year 2003. The reforms have been based on the DRG-system already in operation in another country. Other regulations of the new reform involve the system of quality assurance and quality management in German hospitals and a new form of supply of services, the so called "integrated care" system, the introduction of which was to overcome the fragmented system of ambulatory and stationary medical care in Germany. This article, in short, presents an overview of the hospital sector in Germany and reports on the latest developments resulting from implementation of the health care reform. PMID:11276937

  6. Research in Corporate Communication: An Overview of an Emerging Field.

    ERIC Educational Resources Information Center

    van Riel, Cees B. M.

    1997-01-01

    Provides an overview of research in corporate communication, focusing on achievements found in the international academic literature in both communication and business school disciplines. Gives three key concepts in such research: corporate identity, corporate reputation, and orchestration of communication. Advocates an interdisciplinary approach…

  7. Nanofibers as novel drug carrier--An overview.

    PubMed

    Morie, Asif; Garg, Tarun; Goyal, Amit K; Rath, Goutam

    2016-01-01

    Presently polymer nanofibers have received much attention due to their unique properties such as large surface area, high porosity, small pore size, superior mechanical properties and ease of addition of surface functionalities compared with any other material. Nanofibers particularly polymeric nanofiber prepared by electrospinning process can be used as carriers for the controlled drug delivery of bioactive molecules such as cytokines, growth factors, anticancer drugs, enzymes and certain vitamins. This article presents an overview of nanofibers, various techniques involved in fabrication of nanofibers, their characterization, parameters affecting electrospinning process and their applications. PMID:25016918

  8. Overview of Stellar Pulsations and Driving Mechanisms in Relation to the Evolution of Stars

    NASA Astrophysics Data System (ADS)

    Maeder, A.

    2006-06-01

    An overview of pulsations and instabilities throughout the HR diagram will be presented in relation to a description of the main phases of stellar evolution. The various groups of variable stars will be discussed as well as their properties. We shall also examine the basic physics of stellar pulsations with a particular emphasis on the driving mechanisms. These mechanisms are essentially effects due to stellar opacity and radiation pressure. Radiation also plays a major role in producing stellar winds and the many consequences of these winds on the evolution will be illustrated.

  9. Why pesticides could be a common cause of prostate and breast cancers in the French Caribbean Island, Martinique. An overview on key mechanisms of pesticide-induced cancer.

    PubMed

    Landau-Ossondo, M; Rabia, N; Jos-Pelage, J; Marquet, L M; Isidore, Y; Saint-Aimé, C; Martin, M; Irigaray, P; Belpomme, D

    2009-07-01

    Prostate and breast cancers have become very frequent in Martinique. We previously conducted a multifactorial analysis in the French Caribbean Island, Martinique, in order to elucidate the aetiology of prostate cancer. Using a linear regression analysis, we found that the growth curves of incidence rates for Martinique and metropolitan France have been significantly diverging since 1983. Although a Caribbean genetic susceptibility factor may be involved in prostate carcinogenesis: this factor, because it could not have changed during the observation period, cannot per se account for the growing incidence of this cancer in the island. We therefore suggested that among possible environmental factors, the intensive and prolonged exposure to Carcinogenic, Mutagenic and/or Reprotoxic (CMR) or presumed CMR pesticides may account for the observed growing incidence of prostate cancer and thus may be involved in prostate carcinogenesis. In this study, we further attempt to show that due to their carcinogenic properties, pesticides and especially organochlorine pesticides may in fact be causally implicated in the growing incidence of prostate cancer in Martinique. Also, we suggest that CMR or presumed CMR pesticides may be causally involved in the growing incidence of breast cancer through a common endocrine disruption mechanism. We therefore propose that protective medical recommendations should be immediately set up and carried out by general practitioners, paediatricians, obstetricians, gynaecologists and urologists; and that public health measures of primary precaution and prevention should be urgently taken in close collaboration with health professionals in order to protect population, more especially pregnant women and children, with the final objective perhaps that these medical recommendations and public health measures will stop Martinique's cancer epidemic. PMID:19570649

  10. An Energy Overview of the Slovak Republic

    SciTech Connect

    anon.

    2003-10-20

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Slovakia. The site is designed to be dynamic. Updates to the overviews will be made as need and resource s permit.

  11. Ergonomics and the older worker: an overview.

    PubMed

    Garg, A

    1991-01-01

    Several studies have shown that an individual's capacity for physical and mental work tends to decrease with advancing age. Different capacities begin to deteriorate at different ages and at different rates. However, important bench marks appear to occur in the twenties, forties, and sixties. Ergonomics is the science of fitting the task to the worker. It offers the potential of compensating for the decrease in an individual's functional capacities that occur with age through appropriate job design. Without proper ergonomic job design, older workers could well find themselves at a disadvantage due to compromised productivity and health. This overview will cover the history of ergonomics and its importance in workplace design. The effects of age-related declines on various physical and mental capacities will be reviewed and ergonomic recommendations to accommodate these declines will be presented. To remain competitive in an international marketplace the skills and knowledge of the older worker must be used advantageously. The knowledge required to keep the older worker employed safely and productively can only be acquired through a carefully designed longitudinal study patterned after the Baltimore Longitudinal Study. PMID:1810742

  12. Living Cell Microarrays: An Overview of Concepts.

    PubMed

    Jonczyk, Rebecca; Kurth, Tracy; Lavrentieva, Antonina; Walter, Johanna-Gabriela; Scheper, Thomas; Stahl, Frank

    2016-01-01

    Living cell microarrays are a highly efficient cellular screening system. Due to the low number of cells required per spot, cell microarrays enable the use of primary and stem cells and provide resolution close to the single-cell level. Apart from a variety of conventional static designs, microfluidic microarray systems have also been established. An alternative format is a microarray consisting of three-dimensional cell constructs ranging from cell spheroids to cells encapsulated in hydrogel. These systems provide an in vivo-like microenvironment and are preferably used for the investigation of cellular physiology, cytotoxicity, and drug screening. Thus, many different high-tech microarray platforms are currently available. Disadvantages of many systems include their high cost, the requirement of specialized equipment for their manufacture, and the poor comparability of results between different platforms. In this article, we provide an overview of static, microfluidic, and 3D cell microarrays. In addition, we describe a simple method for the printing of living cell microarrays on modified microscope glass slides using standard DNA microarray equipment available in most laboratories. Applications in research and diagnostics are discussed, e.g., the selective and sensitive detection of biomarkers. Finally, we highlight current limitations and the future prospects of living cell microarrays. PMID:27600077

  13. Living Cell Microarrays: An Overview of Concepts

    PubMed Central

    Jonczyk, Rebecca; Kurth, Tracy; Lavrentieva, Antonina; Walter, Johanna-Gabriela; Scheper, Thomas; Stahl, Frank

    2016-01-01

    Living cell microarrays are a highly efficient cellular screening system. Due to the low number of cells required per spot, cell microarrays enable the use of primary and stem cells and provide resolution close to the single-cell level. Apart from a variety of conventional static designs, microfluidic microarray systems have also been established. An alternative format is a microarray consisting of three-dimensional cell constructs ranging from cell spheroids to cells encapsulated in hydrogel. These systems provide an in vivo-like microenvironment and are preferably used for the investigation of cellular physiology, cytotoxicity, and drug screening. Thus, many different high-tech microarray platforms are currently available. Disadvantages of many systems include their high cost, the requirement of specialized equipment for their manufacture, and the poor comparability of results between different platforms. In this article, we provide an overview of static, microfluidic, and 3D cell microarrays. In addition, we describe a simple method for the printing of living cell microarrays on modified microscope glass slides using standard DNA microarray equipment available in most laboratories. Applications in research and diagnostics are discussed, e.g., the selective and sensitive detection of biomarkers. Finally, we highlight current limitations and the future prospects of living cell microarrays. PMID:27600077

  14. An Overview of Landing Gear Dynamics

    NASA Technical Reports Server (NTRS)

    Pritchard, Jocelyn I.

    1999-01-01

    One of the problems facing the aircraft community is landing gear dynamics, especially shimmy and brake-induced vibration. Although neither shimmy nor brake-induced vibrations are usually catastrophic, they can lead to accidents due to excessive wear and shortened life of gear parts and contribute to pilot and passenger discomfort. Recently, NASA has initiated an effort to increase the safety of air travel by reducing the number of accidents by a factor of five in ten years. This safety initiative has spurred an increased interest in improving landing gear design to minimize shimmy and brake-induced vibration that are still largely misunderstood phenomena. In order to increase the understanding of these problems, a literature survey was performed. The major focus of the paper is to summarize work documented from the last ten years to highlight the latest efforts in solving these vibration problems. Older publications are included to understand the longevity of the problem and the findings from earlier researchers. The literature survey revealed a variety of analyses, testing, modeling, and simulation of aircraft landing gear. Experimental validation and characterization of shimmy and brake-induced vibration of aircraft landing gear are also reported. This paper presents an overview of the problem documented in the references together with a history of landing gear dynamic problems and solutions. Based on the assessment of this survey, recommendations of the most critically needed enhancements to the state of the art are given.

  15. An overview of GNSS remote sensing

    NASA Astrophysics Data System (ADS)

    Yu, Kegen; Rizos, Chris; Burrage, Derek; Dempster, Andrew G.; Zhang, Kefei; Markgraf, Markus

    2014-12-01

    The Global Navigation Satellite System (GNSS) signals are always available, globally, and the signal structures are well known, except for those dedicated to military use. They also have some distinctive characteristics, including the use of L-band frequencies, which are particularly suited for remote sensing purposes. The idea of using GNSS signals for remote sensing - the atmosphere, oceans or Earth surface - was first proposed more than two decades ago. Since then, GNSS remote sensing has been intensively investigated in terms of proof of concept studies, signal processing methodologies, theory and algorithm development, and various satellite-borne, airborne and ground-based experiments. It has been demonstrated that GNSS remote sensing can be used as an alternative passive remote sensing technology. Space agencies such as NASA, NOAA, EUMETSAT and ESA have already funded, or will fund in the future, a number of projects/missions which focus on a variety of GNSS remote sensing applications. It is envisaged that GNSS remote sensing can be either exploited to perform remote sensing tasks on an independent basis or combined with other techniques to address more complex applications. This paper provides an overview of the state of the art of this relatively new and, in some respects, underutilised remote sensing technique. Also addressed are relevant challenging issues associated with GNSS remote sensing services and the performance enhancement of GNSS remote sensing to accurately and reliably retrieve a range of geophysical parameters.

  16. An overview of the HIBISCUS campaign

    NASA Astrophysics Data System (ADS)

    Pommereau, J.-P.; Garnier, A.; Held, G.; Gomes, A.-M.; Goutail, F.; Durry, G.; Borchi, F.; Hauchecorne, A.; Montoux, N.; Cocquerez, P.; Letrenne, G.; Vial, F.; Hertzog, A.; Legras, B.; Pisso, I.; Pyle, J. A.; Harris, N. R. P.; Jones, R. L.; Robinson, A.; Hansford, G.; Eden, L.; Gardiner, T.; Swann, N.; Knudsen, B.; Larsen, N.; Nielsen, J.; Christensen, T.; Cairo, F.; Pirre, M.; Marécal, V.; Huret, N.; Riviére, E.; Coe, H.; Grosvenor, D.; Edvarsen, K.; di Donfrancesco, G.; Ricaud, P.; Berthelier, J.-J.; Godefroy, M.; Seran, E.; Longo, K.; Freitas, S.

    2007-02-01

    HIBISCUS was a field campaign for investigating the impact of deep convection on the Tropical Tropopause Layer (TTL) and the Lower Stratosphere, which took place during the Southern Hemisphere summer in February-March 2004 in the State of São Paulo, Brazil. Its objective was to provide a set of new observational data on meteorology, tracers of horizontal and vertical transport, water vapour, clouds, and chemistry in the tropical UT/LS from balloon observations at local scale over a land convective area, as well as at global scale using circumnavigating long-duration balloons. Overall, the composition of the TTL, the region between 14 and 19 km of intermediate lapse rate between the almost adiabatic upper troposphere and the stable stratosphere, appears highly variable. Tracers and ozone measurements performed at both the local and the global scale indicate a strong quasi-horizontal isentropic exchange with the lowermost mid-latitude stratosphere suggesting that the barrier associated to the tropical jet is highly permeable at these levels in summer. But the project also provides clear indications of strong episodic updraught of cold air, short-lived tracers, low ozone, humidity and ice particles across the lapse rate tropopause at about 15 km, up to 18 or 19 km at 420-440 K potential levels in the lower stratosphere, suggesting that, in contrast to oceanic convection penetrating little the stratosphere, fast daytime developing land convective systems could be a major mechanism in the troposphere-stratosphere exchange at the global scale. The present overview is meant to provide the background of the project, as well as overall information on the instrumental tools available, on the way they have been used within the highly convective context of the South Atlantic Convergence Zone, and a brief summary of the results, which will be detailed in several other papers of this special issue.

  17. The Staphylococci Phages Family: An Overview

    PubMed Central

    Deghorain, Marie; Van Melderen, Laurence

    2012-01-01

    Due to their crucial role in pathogenesis and virulence, phages of Staphylococcus aureus have been extensively studied. Most of them encode and disseminate potent staphylococcal virulence factors. In addition, their movements contribute to the extraordinary versatility and adaptability of this prominent pathogen by improving genome plasticity. In addition to S. aureus, phages from coagulase-negative Staphylococci (CoNS) are gaining increasing interest. Some of these species, such as S. epidermidis, cause nosocomial infections and are therefore problematic for public health. This review provides an overview of the staphylococcal phages family extended to CoNS phages. At the morphological level, all these phages characterized so far belong to the Caudovirales order and are mainly temperate Siphoviridae. At the molecular level, comparative genomics revealed an extensive mosaicism, with genes organized into functional modules that are frequently exchanged between phages. Evolutionary relationships within this family, as well as with other families, have been highlighted. All these aspects are of crucial importance for our understanding of evolution and emergence of pathogens among bacterial species such as Staphylococci. PMID:23342361

  18. Telocyte implications in human pathology: An overview.

    PubMed

    Ibba-Manneschi, Lidia; Rosa, Irene; Manetti, Mirko

    2016-07-01

    Telocytes are a recently described interstitial cell population widely distributed in the stromal compartment of many organs in vertebrates, including humans. Owing to their close spatial relationship with multiple cell types, telocytes are universally considered as 'connecting cells' mostly committed to intercellular signaling by converting the interstitium into an integrated system that drives organ development and contributes to the maintenance of local tissue homeostasis. Increasing evidence indicates that telocytes may cooperate with tissue-resident stem cells to foster organ repair and regeneration, and that telocyte damage and dysfunction may occur in several disorders. The goal of this review is to provide an overview of the most recent findings concerning the implication of telocytes in a variety of pathologic conditions in humans, including heart disease, chronic inflammation and multiorgan fibrosis. Based on recent promising experimental data, there is realistic hope that by targeting telocytes alone or in tandem with stem cells, we might be able to promote organ regeneration and/or prevent irreversible end-stage organ damage in different pathologies. PMID:26805444

  19. An Overview of Landing Gear Dynamics

    NASA Technical Reports Server (NTRS)

    Pritchard, Jocelyn I.

    1999-01-01

    One of the problems facing the aircraft community is landing gear dynamics, especially shimmy and brake-induced vibration. Shimmy and brake-induced vibrations can lead to accidents due to excessive wear and shortened life of gear parts and contribute to pilot and passenger discomfort. To increase understanding of these problems, a literature survey was performed. The major focus is on work from the last ten years. Some older publications are included to understand the longevity of the problem and the background from earlier researchers. The literature survey includes analyses, testing, modeling, and simulation of aircraft landing gear; and experimental validation and characterization of shimmy and brake-induced vibration of aircraft landing gear. The paper presents an overview of the problem, background information, and a history of landing gear dynamics problems and solutions. Based on the survey an assessment and recommendations of the most critically needed enhancements to the state of the art will be presented. The status of Langley work contributing to this activity will be given.

  20. Acute tonsillitis and its complications: an overview.

    PubMed

    Bartlett, A; Bola, S; Williams, R

    2015-01-01

    Acute tonsillitis may be defined as inflammation of the tonsils, predominantly due to infection. It is part of the spectrum of pharyngitis, which ranges from localised tonsillar infection to generalised infection of the pharynx and commonly affects young healthy adults. Simple sore throats secondary to viral or bacterial pharyngitis are very common and generally do not require hospital admission or antimicrobial treatment. Supportive management in the form of analgesia and adequate hydration is often sufficient. However, there is potential for life-threatening complications to develop, highlighting the need for basic knowledge in the management of these conditions. This article aims to provide an overview of acute tonsillitis and its complications, including peritonsillar and parapharyngeal abscess formation. Specific attention will be given to the pathogenesis, diagnosis, investigation and management of each condition, in particular advising on emergency pre-shore treatment and indications for referral to an Ear, Nose and Throat Department. We will also summarise important guidelines and evidence from the literature to support these management decisions. PMID:26292396

  1. Extreme winds and tornadoes: an overview

    SciTech Connect

    McDonald, J.R.

    1985-01-01

    The objective of this course on extreme winds, hurricanes and tornadoes is to provide an overview of these natural phenomenon from the perspective of design of new buildings and structures or the evaluation of existing ones. Information is directly applicable to design and evaluation processes. The premise is that the facility under consideration, which may consist of various buildings, structures, processing equipment, stacks, ventilation ducts, etc., can be classified into certain categories, depending on the importance of the mission performed in the facility or the hazard that is presented by the particular operation. Having classified the facility into an appropriate category will automatically define certain design goals for the facility. The design goals are then met by selecting a design wind speed that is appropriate for the specified exceedance probability and by following certain specified design procedures. The problem then is to determine appropriate wind loads and other applicable loads, including dead loads, live loads, seismic loads and other loads that may act on the structures. The design process can then proceed in the usual manner. In the case of existing facilities the strengths of the various structural elements, subsystems and systems are evaluated and these strengths are related to wind speeds that would result in failure to meet the design goals. 12 refs.

  2. Overview of an Algorithm Plugin Package (APP)

    NASA Astrophysics Data System (ADS)

    Linda, M.; Tilmes, C.; Fleig, A. J.

    2004-12-01

    Science software that runs operationally is fundamentally different than software that runs on a scientist's desktop. There are complexities in hosting software for automated production that are necessary and significant. Identifying common aspects of these complexities can simplify algorithm integration. We use NASA's MODIS and OMI data production systems as examples. An Algorithm Plugin Package (APP) is science software that is combined with algorithm-unique elements that permit the algorithm to interface with, and function within, the framework of a data processing system. The framework runs algorithms operationally against large quantities of data. The extra algorithm-unique items are constrained by the design of the data processing system. APPs often include infrastructure that is vastly similar. When the common elements in APPs are identified and abstracted, the cost of APP development, testing, and maintenance will be reduced. This paper is an overview of the extra algorithm-unique pieces that are shared between MODAPS and OMIDAPS APPs. Our exploration of APP structure will help builders of other production systems identify their common elements and reduce algorithm integration costs. Our goal is to complete the development of a library of functions and a menu of implementation choices that reflect common needs of APPs. The library and menu will reduce the time and energy required for science developers to integrate algorithms into production systems.

  3. Volatiles and Fluids in Subduction Zones: Climate Feedback and Trigger Mechanisms for Natural Disasters. An Overview of the Activities of SFB 574.

    NASA Astrophysics Data System (ADS)

    Reston, T. J.

    2005-12-01

    The special research program SFB 574 at the University of Kiel investigates the role of fluid and volatile recycling in subduction zones along the Central American convergent margin (Guatemala to Panama) through integrated geophysical, geological, volcanological, geochemical, petrological and oceanographic studies. The work is carried out by over 50 scientists within 12 focussed scientific projects, evenly distributed between the tectonics of the subduction zone, the dewatering through the forearc, and the transfer of fluids from the slab to the atmosphere through the arc. During Phase I (2001-2004), we concentrated on a segment of the erosive subduction zone system onshore and offshore Costa Rica and Nicaragua, one of the focus areas for the MARGIN initiatives SubFac and SEIZE. Along this margin, the dip of subduction, the nature of the incoming plate, and magmatic compositions along the volcanic arc are all known to change significantly. In addition to work carried out during cruises and fieldwork from the 1990s, in the past 4 years we have collected new data during a total 10 months of shiptime on the research vessels SONNE and METEOR, and during 20 man-months of fieldwork, mainly in Costa Rica and Nicaragua. In Phase II (2004-2008) we will finish work off Central America, and start working in an accretionary segment of the Chile margin between 32 and 38S. In this presentation I outline some of the main results concentrating on the effect of variable input and on the output at the arc. Key effects include the influence of the Galapagos hotspot on the incoming section (and on the output at the arc), the thickness of the volcanic crust and the effects of mantle serpentinization.

  4. An overview of genetic counseling in Cuba.

    PubMed

    Cruz, Araceli Lantigua

    2013-12-01

    This brief report provides an overview of the history and current status of genetic services in Cuba. In 1971, the University of Medical Sciences of Havana began to train doctors in medical genetics according to the medicine development plan in Cuba. With the aim of introducing genetic services to the population, two main issues were identified: the impact of neural tube defects as a cause of infantile mortality, and a founder effect resulting in a high frequency of sickle cell anemia, which increased the mortality rate and impacted the quality of peoples' lives. The impact of consanguinity is variable; it depends on the isolation of the population, with rates of 1 to 11% in different regions for first and second cousin marriages. From 1981, the services of medical genetics began to expand to the entire country, according to a government directive, and the need to design a program for the specialty became evident. From 1995 to 2000, two Masters-level programs were designed by professors of the Department of Medical Genetics, University of Medical Sciences of Havana, and authorized by the Ministry of Higher Education. One program in medical genetics was designed for physicians with other specialties, and the second program was designed to train professionals to become genetic counselors. The majority of graduates from the latter program are working at the primary level of healthcare. PMID:23934326

  5. Management of thoracolumbar spine trauma: An overview

    PubMed Central

    Rajasekaran, S; Kanna, Rishi Mugesh; Shetty, Ajoy Prasad

    2015-01-01

    Thoracolumbar spine fractures are common injuries that can result in significant disability, deformity and neurological deficit. Controversies exist regarding the appropriate radiological investigations, the indications for surgical management and the timing, approach and type of surgery. This review provides an overview of the epidemiology, biomechanical principles, radiological and clinical evaluation, classification and management principles. Literature review of all relevant articles published in PubMed covering thoracolumbar spine fractures with or without neurologic deficit was performed. The search terms used were thoracolumbar, thoracic, lumbar, fracture, trauma and management. All relevant articles and abstracts covering thoracolumbar spine fractures with and without neurologic deficit were reviewed. Biomechanically the thoracolumbar spine is predisposed to a higher incidence of spinal injuries. Computed tomography provides adequate bony detail for assessing spinal stability while magnetic resonance imaging shows injuries to soft tissues (posterior ligamentous complex [PLC]) and neurological structures. Different classification systems exist and the most recent is the AO spine knowledge forum classification of thoracolumbar trauma. Treatment includes both nonoperative and operative methods and selected based on the degree of bony injury, neurological involvement, presence of associated injuries and the integrity of the PLC. Significant advances in imaging have helped in the better understanding of thoracolumbar fractures, including information on canal morphology and injury to soft tissue structures. The ideal classification that is simple, comprehensive and guides management is still elusive. Involvement of three columns, progressive neurological deficit, significant kyphosis and canal compromise with neurological deficit are accepted indications for surgical stabilization through anterior, posterior or combined approaches. PMID:25593358

  6. The problem of active SETI: An overview

    NASA Astrophysics Data System (ADS)

    Musso, Paolo

    2012-09-01

    In the present paper (originally presented at the First IAA Symposium on Searching for Life Signatures hold at the UNESCO on 22-26 September 2008) I try to summarize the results of all my previous studies on active SETI and its possible dangers for us, also considering some new topics, in order to provide a possibly complete overview of the whole matter. First, I try to evaluate the possible risks of an indirect contact with aliens, from the social, cultural, and religious point of view; then, the possible risks related with receiving information about alien science and technology; finally, the risk that active SETI could increase the probability of a physical contact with hostile aliens. My conclusion is that active SETI is very unlikely to be dangerous for us, but, at present, such a possibility cannot be completely excluded. Surprisingly, it turns out that a very important point to be assessed in order to improve our evaluation of active SETI is the pace of our technological progress. Some suggestions about the policy that international community should adopt towards active SETI are also included.

  7. [Health conferences in Germany: an overview].

    PubMed

    Hollederer, A

    2015-03-01

    Health conferences are a special management instrument of health policy. Less is known about the distribution. There is a lack of systematic evaluation methods.This overview is based on comprehensive literature, data base and internet searches about health conferences in Germany.The establishment of structured conferences is derived from funding projects of the federal states or local initiatives which began in different phases and with various emphases. The strategies varied from individual actions to an implementation in the whole state. Currently there are altogether 130 health conferences in Germany for approximately one third of the county and city districts in 13 federal states. The federal states assist health conferences by providing financial support, health policy, support by health authorities and regulations in the law. In the majority of the cases the office is located within the public health service. There is a great diversity in the composition of the stakeholders and in the contents. A systematic monitoring and outcome evaluation was conducted only in a few cases. Those studies predominantly report positive results but also promoting and inhibiting factors. They referred to restrictions.Health conferences are broadly disseminated, especially in west Germany. They offer opportunities for a community health management. There is a need for more intensive exchange and evaluation to improve their development. PMID:24420647

  8. CFD for wastewater treatment: an overview.

    PubMed

    Samstag, R W; Ducoste, J J; Griborio, A; Nopens, I; Batstone, D J; Wicks, J D; Saunders, S; Wicklein, E A; Kenny, G; Laurent, J

    2016-01-01

    Computational fluid dynamics (CFD) is a rapidly emerging field in wastewater treatment (WWT), with application to almost all unit processes. This paper provides an overview of CFD applied to a wide range of unit processes in water and WWT from hydraulic elements like flow splitting to physical, chemical and biological processes like suspended growth nutrient removal and anaerobic digestion. The paper's focus is on articulating the state of practice and research and development needs. The level of CFD's capability varies between different process units, with a high frequency of application in the areas of final sedimentation, activated sludge basin modelling and disinfection, and greater needs in primary sedimentation and anaerobic digestion. While approaches are comprehensive, generally capable of incorporating non-Newtonian fluids, multiphase systems and biokinetics, they are not broad, and further work should be done to address the diversity of process designs. Many units have not been addressed to date. Further needs are identified throughout, but common requirements include improved particle aggregation and breakup (flocculation), and improved coupling of biology and hydraulics. PMID:27508360

  9. Spaceflight-Induced Intracranial Hypertension: An Overview

    NASA Technical Reports Server (NTRS)

    Traver, William J.

    2011-01-01

    This slide presentation is an overview of the some of the known results of spaceflight induced intracranial hypertension. Historical information from Gemini 5, Apollo, and the space shuttle programs indicated that some vision impairment was reported and a comparison between these historical missions and present missions is included. Optic Disc Edema, Globe Flattening, Choroidal Folds, Hyperopic Shifts and Raised Intracranial Pressure has occurred in Astronauts During and After Long Duration Space Flight. Views illustrate the occurrence of Optic Disc Edema, Globe Flattening, and Choroidal Folds. There are views of the Arachnoid Granulations and Venous return, and the question of spinal or venous compliance issues is discussed. The question of increased blood flow and its relation to increased Cerebrospinal fluid (CSF) is raised. Most observed on-orbit papilledema does not progress, and this might be a function of plateau homeostasis for the higher level of intracranial pressure. There are seven cases of astronauts experiencing in flight and post flight symptoms, which are summarized and follow-up is reviewed along with a comparison of the treatment options. The question is "is there other involvement besides vision," and other Clinical implications are raised,

  10. An overview of South African psychology.

    PubMed

    Cooper, Saths; Nicholas, Lionel

    2012-01-01

    This overview of psychology in South Africa presents a concise and historical account of its science and practice, from its early origins in the late nineteenth century to the present, and traces seminal influences on the discipline. It is a review of how psychology in South Africa developed over more than a century to become one of the most popular subjects in universities and an established and recognized profession, whose members play a variety of roles in the South African polity and larger society. The impact that apartheid racism had on key aspects of psychology's development is traversed, and the influences that previous ruling party politics had on professional psychological organizations are delineated. The unification of psychology under the Psychological Society of South Africa, a few months before the advent of democracy in South Africa, is explicated. The protection of the title of psychologist in law and certain other changes in the legislative environment, enabling a greater role for psychologists, are reported. The primary research sites for psychology and its funding and the main university psychology programs are described, as are the requirements for registration and licensure. The genesis and the importance of the work of internationally acclaimed South African psychologists, such as J. Wolpe and A. A. Lazarus, are contextualized. With the increased participation of progressive black psychologists in leadership and research in the past two decades, a transformed psychology has the potential to play a significant role in addressing human issues confronting South Africa. PMID:22432681

  11. The National Energy Modeling System: An overview

    SciTech Connect

    Not Available

    1994-05-01

    The National Energy Modeling System (NEMS) is a computer-based, energy-economy modeling system of US energy markets for the midterm period of 1990 to 2010. NEMS projects the production, imports, conversion, consumption, and prices of energy, subject to assumptions on macroeconomic and financial factors, world energy markets, resource availability and costs, behavioral and technological choice criteria, cost and performance characteristics of energy technologies, and demographics. This report presents an overview of the structure and methodology of NEMS and each of its components. The first chapter provides a description of the design and objectives of the system. The second chapter describes the modeling structure. The remainder of the report summarizes the methodology and scope of the component modules of NEMS. The model descriptions are intended for readers familiar with terminology from economics, operations research, and energy modeling. Additional background on the development of the system is provided in Appendix A of this report, which describes the EIA modeling systems that preceded NEMS. More detailed model documentation reports for all the NEMS modules are also available from EIA.

  12. The Practice of Campus-Based Threat Assessment: An Overview

    ERIC Educational Resources Information Center

    Pollard, Jeffrey W.; Nolan, Jeffrey J.; Deisinger, Eugene R. D.

    2012-01-01

    This article provides an overview of threat assessment and management as implemented on campuses of higher education. Standards of practice and state calls for implementation are cited. An overview of some of the basic principles for threat assessment and management implementation is accompanied by examples of how they are utilized. Pitfalls…

  13. Targeted radionuclide therapy--an overview.

    PubMed

    Dash, Ashutosh; Knapp, F F Russ; Pillai, M R A

    2013-09-01

    Radionuclide therapy (RNT) based on the concept of delivering cytotoxic levels of radiation to disease sites is one of the rapidly growing fields of nuclear medicine. Unlike conventional external beam therapy, RNT targets diseases at the cellular level rather than on a gross anatomical level. This concept is a blend of a tracer moiety that mediates a site specific accumulation followed by induction of cytotoxicity with the short-range biological effectiveness of particulate radiations. Knowledge of the biochemical reactions taking place at cellular levels has stimulated the development of sophisticated molecular carriers, catalyzing a shift towards using more specific targeting radiolabelled agents. There is also improved understanding of factors of importance for choice of appropriate radionuclides based on availability, the types of emissions, linear energy transfer (LET), and physical half-life. This article discusses the applications of radionuclide therapy for treatment of cancer as well as other diseases. The primary objective of this review is to provide an overview on the role of radionuclide therapy in the treatment of different diseases such as polycythaemia, thyroid malignancies, metastatic bone pain, radiation synovectomy, hepatocellular carcinoma (HCC), neuroendocrine tumors (NETs), non-Hodgkin's lymphoma (NHL) and others. In addition, recent developments on the systematic approach in designing treatment regimens as well as recent progress, challenges and future perspectives are discussed. An examination of the progress of radionuclide therapy indicates that although a rapid stride has been made for treating hematological tumors, the development for treating solid tumors has, so far, been limited. However, the emergence of novel tumor-specific targeting agents coupled with successful characterization of new target structures would be expected to pave the way for future treatment for such tumors. PMID:24059327

  14. An overview of tumorous diseases of turkeys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This overview is primarily aimed at addressing various aspects of virus-induced tumorous diseases of turkeys including review of current methods for diagnosis and control of these diseases of turkeys. Virus-induced tumorous diseases of turkeys are caused primarily by retroviruses, namely reticuloend...

  15. Charter Schools in Texas: An Overview

    ERIC Educational Resources Information Center

    Penning, Francisco; Slate, John R.

    2011-01-01

    In this article we analyzed the literature regarding charter schools in the State of Texas. We specifically examined the evolution of the charter school movement in Texas. Moreover, data regarding the effectiveness/ineffectiveness of charter schools in Texas were discussed. Our overview of Texas charter schools, given their widespread presence in…

  16. Atmospheric laser Doppler velocimetry - An overview

    NASA Technical Reports Server (NTRS)

    Bilbro, J. W.

    1980-01-01

    Research, development, and application of atmospheric laser Doppler velocimetry are overviewed. Consideration is given to operation principles of CO2 heterodyne systems. Global wind, pollution, V/STOL flow, and true airspeed measurements are outlined. Wind energy, dust devils, water spouts, tornadoes, and aircraft wake vortices are covered.

  17. Child Welfare in 25 States: An Overview.

    ERIC Educational Resources Information Center

    National Center for Child Advocacy (DHEW/OHD), Washington, DC.

    This overview presents a summary of the major findings of a 25-state survey of child welfare service delivery systems, as studied by Peat, Marwick, Mitchell & Co. in association with the Child Welfare League of America (CWLA) during the period of November 1975 through February 1976. The initial products of the survey were 25 state profiles; these…

  18. The Urban Learner Framework: An Overview.

    ERIC Educational Resources Information Center

    Kinney, David A.; And Others

    The Urban Education staff at Research for Better Schools (RBS), Inc., has developed a conceptual framework to address the complex issues that must be dealt with in urban school-restructuring efforts. This overview of the Urban Learner Framework (ULF) describes its two major features: four research-based themes that are the foundation for a new…

  19. Electronic waste management approaches: An overview

    SciTech Connect

    Kiddee, Peeranart; Naidu, Ravi; Wong, Ming H.

    2013-05-15

    Highlights: ► Human toxicity of hazardous substances in e-waste. ► Environmental impacts of e-waste from disposal processes. ► Life Cycle Assessment (LCA), Material Flow Analysis (MFA), Multi Criteria Analysis (MCA) and Extended Producer Responsibility (EPR) to and solve e-waste problems. ► Key issues relating to tools managing e-waste for sustainable e-waste management. - Abstract: Electronic waste (e-waste) is one of the fastest-growing pollution problems worldwide given the presence if a variety of toxic substances which can contaminate the environment and threaten human health, if disposal protocols are not meticulously managed. This paper presents an overview of toxic substances present in e-waste, their potential environmental and human health impacts together with management strategies currently being used in certain countries. Several tools including Life Cycle Assessment (LCA), Material Flow Analysis (MFA), Multi Criteria Analysis (MCA) and Extended Producer Responsibility (EPR) have been developed to manage e-wastes especially in developed countries. The key to success in terms of e-waste management is to develop eco-design devices, properly collect e-waste, recover and recycle material by safe methods, dispose of e-waste by suitable techniques, forbid the transfer of used electronic devices to developing countries, and raise awareness of the impact of e-waste. No single tool is adequate but together they can complement each other to solve this issue. A national scheme such as EPR is a good policy in solving the growing e-waste problems.

  20. Overview: Mechanism and Control of a Prosthetic Arm.

    PubMed

    Kulkarni, Tushar; Uddanwadiker, Rashmi

    2015-09-01

    Continuous growth in industrialization and lack of awareness in safety parameters the cases of amputations are growing. The search of safer, simpler and automated prosthetic arms for managing upper limbs is expected. Continuous efforts have been made to design and develop prosthetic arms ranging from simple harness actuated to automated mechanisms with various control options. However due the cost constraints, the automated prosthetic arms are still out of the reach of needy people. Recent data have shown that there is a wide scope to develop a low cost and light weight upper limb prosthesis. This review summarizes the various designs methodologies, mechanisms and control system developed by the researchers and the advances therein. Educating the patient to develop acceptability to prosthesis and using the same for the most basic desired functions of human hand, post amputation care and to improve patient's independent life is equally important. In conclusion it can be interpreted that there is a wide scope in design in an adaptive mechanism for opening and closing of the fingers using other methods of path and position synthesis. Simple mechanisms and less parts may optimize the cost factor. Reduction in the weight of the prosthesis may be achieved using polymers used for engineering applications. Control system will remain never ending challenge for the researchers, but it is essential to maintain the simplicity from the patients perspective. PMID:27281955

  1. An Overview of Electronic Passport Security Features

    NASA Astrophysics Data System (ADS)

    Říha, Zdeněk

    Electronic passports include contactless chip which stores personal data of the passport holder, information about the passport and the issuing institution. In its simplest form an electronic passport contains just a collection of read-only files, more advanced variants can include sophisticated cryptographic mechanisms protecting security of the document and / or privacy of the passport holder. This paper describes security features of electronic passports and discusses their efficiency.

  2. Microbial biofilms in intertidal systems: an overview

    NASA Astrophysics Data System (ADS)

    Decho, Alan W.

    2000-07-01

    Intertidal marine systems are highly dynamic systems which are characterized by periodic fluctuations in environmental parameters. Microbial processes play critical roles in the remineralization of nutrients and primary production in intertidal systems. Many of the geochemical and biological processes which are mediated by microorganisms occur within microenvironments which can be measured over micrometer spatial scales. These processes are localized by cells within a matrix of extracellular polymeric secretions (EPS), collectively called a "microbial biofilm". Recent examinations of intertidal systems by a range of investigators using new approaches show an abundance of biofilm communities. The purpose of this overview is to examine recent information concerning the roles of microbial biofilms in intertidal systems. The microbial biofilm is a common adaptation of natural bacteria and other microorganisms. In the fluctuating environments of intertidal systems, biofilms form protective microenvironments and may structure a range of microbial processes. The EPS matrix of biofilm forms sticky coatings on individual sediment particles and detrital surfaces, which act as a stabilizing anchor to buffer cells and their extracellular processes during the frequent physical stresses (e.g., changes in salinity and temperature, UV irradiation, dessication). EPS is an operational definition designed to encompass a range of large microbially-secreted molecules having widely varying physical and chemical properties, and a range of biological roles. Examinations of EPS using Raman and Fourier-transform infared spectroscopy, and atomic-force microscopy suggest that some EPS gels possess physical and chemical properties which may hasten the development of sharp geochemical gradients, and contribute a protective effect to cells. Biofilm polymers act as a sorptive sponge which binds and concentrates organic molecules and ions close to cells. Concurrently, the EPS appear to localize

  3. Data Streams: An Overview and Scientific Applications

    NASA Astrophysics Data System (ADS)

    Aggarwal, Charu C.

    In recent years, advances in hardware technology have facilitated the ability to collect data continuously. Simple transactions of everyday life such as using a credit card, a phone, or browsing the web lead to automated data storage. Similarly, advances in information technology have lead to large flows of data across IP networks. In many cases, these large volumes of data can be mined for interesting and relevant information in a wide variety of applications. When the volume of the underlying data is very large, it leads to a number of computational and mining challenges: With increasing volume of the data, it is no longer possible to process the data efficiently by using multiple passes. Rather, one can process a data item at most once. This leads to constraints on the implementation of the underlying algorithms. Therefore, stream mining algorithms typically need to be designed so that the algorithms work with one pass of the data. In most cases, there is an inherent temporal component to the stream mining process. This is because the data may evolve over time. This behavior of data streams is referred to as temporal locality. Therefore, a straightforward adaptation of one-pass mining algorithms may not be an effective solution to the task. Stream mining algorithms need to be carefully designed with a clear focus on the evolution of the underlying data. Another important characteristic of data streams is that they are often mined in a distributed fashion. Furthermore, the individual processors may have limited processing and memory. Examples of such cases include sensor networks, in which it may be desirable to perform in-network processing of data stream with limited processing and memory [1, 2]. This chapter will provide an overview of the key challenges in stream mining algorithms which arise from the unique setup in which these problems are encountered. This chapter is organized as follows. In the next section, we will discuss the generic challenges that

  4. Role of Pharmacovigilance in India: An overview.

    PubMed

    Suke, Sanvidhan G; Kosta, Prabhat; Negi, Harsh

    2015-01-01

    Pharmacovigilance (PV) plays a key role in the healthcare system through assessment, monitoring and discovery of interactions amongst drugs and their effects in human. Pharmaceutical and biotechnological medicines are designed to cure, prevent or treat diseases; however, there are also risks particularly adverse drug reactions (ADRs) can cause serious harm to patients. Thus, for safety medication ADRs monitoring required for each medicine throughout its life cycle, during development of drug such as pre-marketing including early stages of drug design, clinical trials, and post-marketing surveillance. PV is concerns with the detection, assessment, understanding and prevention of ADRs. Pharmacogenetics and pharmacogenomics are an indispensable part of the clinical research. Variation in the human genome is a cause of variable response to drugs and susceptibility to diseases are determined, which is important for early drug discovery to PV. Moreover, PV has traditionally involved in mining spontaneous reports submitted to national surveillance systems. The research focus is shifting toward the use of data generated from platforms outside the conventional framework such as electronic medical records, biomedical literature, and patient-reported data in health forums. The emerging trend in PV is to link premarketing data with human safety information observed in the post-marketing phase. The PV system team obtains valuable additional information, building up the scientific data contained in the original report and making it more informative. This necessitates an utmost requirement for effective regulations of the drug approval process and conscious pre and post approval vigilance of the undesired effects, especially in India. Adverse events reported by PV system potentially benefit to the community due to their proximity to both population and public health practitioners, in terms of language and knowledge, enables easy contact with reporters by electronically. Hence, PV

  5. Role of Pharmacovigilance in India: An overview

    PubMed Central

    Suke, Sanvidhan G; Kosta, Prabhat; Negi, Harsh

    2015-01-01

    Pharmacovigilance (PV) plays a key role in the healthcare system through assessment, monitoring and discovery of interactions amongst drugs and their effects in human. Pharmaceutical and biotechnological medicines are designed to cure, prevent or treat diseases; however, there are also risks particularly adverse drug reactions (ADRs) can cause serious harm to patients. Thus, for safety medication ADRs monitoring required for each medicine throughout its life cycle, during development of drug such as pre-marketing including early stages of drug design, clinical trials, and post-marketing surveillance. PV is concerns with the detection, assessment, understanding and prevention of ADRs. Pharmacogenetics and pharmacogenomics are an indispensable part of the clinical research. Variation in the human genome is a cause of variable response to drugs and susceptibility to diseases are determined, which is important for early drug discovery to PV. Moreover, PV has traditionally involved in mining spontaneous reports submitted to national surveillance systems. The research focus is shifting toward the use of data generated from platforms outside the conventional framework such as electronic medical records, biomedical literature, and patient-reported data in health forums. The emerging trend in PV is to link premarketing data with human safety information observed in the post-marketing phase. The PV system team obtains valuable additional information, building up the scientific data contained in the original report and making it more informative. This necessitates an utmost requirement for effective regulations of the drug approval process and conscious pre and post approval vigilance of the undesired effects, especially in India. Adverse events reported by PV system potentially benefit to the community due to their proximity to both population and public health practitioners, in terms of language and knowledge, enables easy contact with reporters by electronically. Hence, PV

  6. Chemical contaminants in human milk: an overview.

    PubMed Central

    Sonawane, B R

    1995-01-01

    This review contains a succinct overview of the nature and extent of the problem of contamination of human milk with environmental and occupational chemicals, excluding drugs. Factors influencing the levels of contaminants in breast milk are discussed. Also, data on major chemicals of concern with potential health risk(s) to the general population and risk-benefit considerations are dealt with briefly. Based on the available data on the subject, research needs have been identified and policy recommendations are suggested. PMID:8549474

  7. Poland: An energy and environmental overview

    SciTech Connect

    Szpunar, C.B.; Bhatti, N.; Buehring, W.A.; Streets, D.G. ); Balandynowicz, H.W. . Inst. Podstawowych Problemow Techniki)

    1990-10-01

    Poland's reliance on coal as its primary source of energy imposes heavy environmental costs on its economy and population. Specifically, many of Poland's air and water pollution problems can be traced to the high energy intensity of Polish industrial production. This overview presents environment and energy information for Poland. Topics discussed include: energy resources, production and use; energy production, trade and use; environmental quality and impacts; and control strategies. 109 refs., 25 figs., 40 tabs.

  8. Overview of the NASA program in computational structural mechanics

    NASA Technical Reports Server (NTRS)

    Hirschbein, Murray

    1989-01-01

    In order to meet the anticipated needs in modeling and analysis of advanced aerospace structures, NASA has developed a program focused on computational structural mechanics. The objective of this program is to advance the state-of-the-art in computational analysis to make accurate analysis of very large and complex structural problems routine. This will be accomplished by emphasizing two key areas: (1) the development of advanced analytical methods, extending beyond traditional approaches and, (2) the exploitation of the newest and most powerful parallel/multiprocessor computers available. Computational testbeds will be developed to serve as technology integrators and to promote/accelerate methodology research and development. An additional, and highly desirable, effect of the Computational Structural Mechanics (CSM) program would be to influence the design of future hardware and software systems to reflect the needs of structural analysis.

  9. An overview of macroautophagy in yeast.

    PubMed

    Wen, Xin; Klionsky, Daniel J

    2016-05-01

    Macroautophagy is an evolutionarily conserved dynamic pathway that functions primarily in a degradative manner. A basal level of macroautophagy occurs constitutively, but this process can be further induced in response to various types of stress including starvation, hypoxia and hormonal stimuli. The general principle behind macroautophagy is that cytoplasmic contents can be sequestered within a transient double-membrane organelle, an autophagosome, which subsequently fuses with a lysosome or vacuole (in mammals, or yeast and plants, respectively), allowing for degradation of the cargo followed by recycling of the resulting macromolecules. Through this basic mechanism, macroautophagy has a critical role in cellular homeostasis; however, either insufficient or excessive macroautophagy can seriously compromise cell physiology, and thus, it needs to be properly regulated. In fact, a wide range of diseases are associated with dysregulation of macroautophagy. There has been substantial progress in understanding the regulation and molecular mechanisms of macroautophagy in different organisms; however, many questions concerning some of the most fundamental aspects of macroautophagy remain unresolved. In this review, we summarize current knowledge about macroautophagy mainly in yeast, including the mechanism of autophagosome biogenesis, the function of the core macroautophagic machinery, the regulation of macroautophagy and the process of cargo recognition in selective macroautophagy, with the goal of providing insights into some of the key unanswered questions in this field. PMID:26908221

  10. Medical smart textiles based on fiber optic technology: an overview.

    PubMed

    Massaroni, Carlo; Saccomandi, Paola; Schena, Emiliano

    2015-01-01

    The growing interest in the development of smart textiles for medical applications is driven by the aim to increase the mobility of patients who need a continuous monitoring of such physiological parameters. At the same time, the use of fiber optic sensors (FOSs) is gaining large acceptance as an alternative to traditional electrical and mechanical sensors for the monitoring of thermal and mechanical parameters. The potential impact of FOSs is related to their good metrological properties, their small size and their flexibility, as well as to their immunity from electromagnetic field. Their main advantage is the possibility to use textile based on fiber optic in a magnetic resonance imaging environment, where standard electronic sensors cannot be employed. This last feature makes FOSs suitable for monitoring biological parameters (e.g., respiratory and heartbeat monitoring) during magnetic resonance procedures. Research interest in combining FOSs and textiles into a single structure to develop wearable sensors is rapidly growing. In this review we provide an overview of the state-of-the-art of textiles, which use FOSs for monitoring of mechanical parameters of physiological interest. In particular we briefly describe the working principle of FOSs employed in this field and their relevant advantages and disadvantages. Also reviewed are their applications for the monitoring of mechanical parameters of physiological interest. PMID:25871010

  11. Medical Smart Textiles Based on Fiber Optic Technology: An Overview

    PubMed Central

    Massaroni, Carlo; Saccomandi, Paola; Schena, Emiliano

    2015-01-01

    The growing interest in the development of smart textiles for medical applications is driven by the aim to increase the mobility of patients who need a continuous monitoring of such physiological parameters. At the same time, the use of fiber optic sensors (FOSs) is gaining large acceptance as an alternative to traditional electrical and mechanical sensors for the monitoring of thermal and mechanical parameters. The potential impact of FOSs is related to their good metrological properties, their small size and their flexibility, as well as to their immunity from electromagnetic field. Their main advantage is the possibility to use textile based on fiber optic in a magnetic resonance imaging environment, where standard electronic sensors cannot be employed. This last feature makes FOSs suitable for monitoring biological parameters (e.g., respiratory and heartbeat monitoring) during magnetic resonance procedures. Research interest in combining FOSs and textiles into a single structure to develop wearable sensors is rapidly growing. In this review we provide an overview of the state-of-the-art of textiles, which use FOSs for monitoring of mechanical parameters of physiological interest. In particular we briefly describe the working principle of FOSs employed in this field and their relevant advantages and disadvantages. Also reviewed are their applications for the monitoring of mechanical parameters of physiological interest. PMID:25871010

  12. An overview of statistical learning theory.

    PubMed

    Vapnik, V N

    1999-01-01

    Statistical learning theory was introduced in the late 1960's. Until the 1990's it was a purely theoretical analysis of the problem of function estimation from a given collection of data. In the middle of the 1990's new types of learning algorithms (called support vector machines) based on the developed theory were proposed. This made statistical learning theory not only a tool for the theoretical analysis but also a tool for creating practical algorithms for estimating multidimensional functions. This article presents a very general overview of statistical learning theory including both theoretical and algorithmic aspects of the theory. The goal of this overview is to demonstrate how the abstract learning theory established conditions for generalization which are more general than those discussed in classical statistical paradigms and how the understanding of these conditions inspired new algorithmic approaches to function estimation problems. A more detailed overview of the theory (without proofs) can be found in Vapnik (1995). In Vapnik (1998) one can find detailed description of the theory (including proofs). PMID:18252602

  13. The Drop Tower Bremen -An Overview

    NASA Astrophysics Data System (ADS)

    von Kampen, Peter; Könemann, Thorben; Rath, Hans J.

    Hz) demonstrates a perfect experimental environment for unperturbed investigations of scientific phenomena. Motivated by these prospects many national and international groups have initialized research programs taking advantage of this drop tower facility. In respect thereof the spectrum of research fields and technologies in space-related conditions can be continuously enhanced at ZARM. In the first of our two talks we will give you an overview about the inner structure of ZARM, as well as the service and the operation offered by the ZARM Drop Tower Operation and Service Company (ZARM FAB mbH). The ZARM FAB mbH owned by the State Government of Bremen is a public company maintaining the drop tower facility and supporting experimentalists in scientific and technical questions before, during and after their drop or catapult campaigns. In detail, we will present you important technical drop tower informations, our support and the idea, how you can proceed with your microgravity-related experiment including all your requirements to successfully accomplish an entire drop or catapult campaign. In summary, we will illustrate the complete procedure, how to drop or to catapult an experiment capsule at the Drop Tower Bremen.

  14. Nickel-Hydrogen Batteries - An Overview

    NASA Technical Reports Server (NTRS)

    Smithrick, John J.; ODonnell, Patricia M.

    1996-01-01

    This article on nickel-hydrogen batteries is an overview of the various nickel-hydrogen battery design options, technical accomplishments, validation test results, and trends. There is more than one nickel-hydrogen battery design, each having its advantage for specific applications. The major battery designs are Individual Pressure Vessel (IPV), Common Pressure Vessel (CPV), bipolar, and low-pressure metal hydride. State-of-the-art nickel-hydrogen batteries are replacing nickel-cadmium batteries in almost all geosynchronous Earth orbit applications requiring power above 1 kW. However, for the more severe Low-Earth Orbit (LEO) applications (greater than 30,000 cycles), the current cycle life of 4000-10,000 cycles at 60 - 80 % DOD should be improved. A NASA Lewis Research Center innovative advanced design IPV nickel-hydrogen cell led to a breakthrough in cycle life enabling LEO applications at deep Depths of Discharge (DOD). A trend for some future satellites is to increase the power level to greater than 6 kW. Another trend is to decrease the power to less than 1 kW for small low-cost satellites. Hence, the challenge is to reduce battery mass, volume, and cost. A key is to develop a lightweight nickel electrode and alternate battery designs. A CPV nickel-hydrogen battery is emerging as a viable alternative to the IPV design. It has the advantage of reduced mass, volume, and manufacturing costs. A 10-A-h CPV battery has successfully provided power on the relatively short-lived Clementine spacecraft. A bipolar nickel -hydrogen battery design has been demonstrated (15,000 LEO cycles, 40 % DOD). The advantage is also a significant reduction in volume, a modest reduction in mass, and like most bipolar designs, features a high-pulse power capability. A low-pressure aerospace nickel-metal-hydride battery cell has been developed and is on the market. It is a prismatic design that has the advantage of a significant reduction in volume and a reduction in manufacturing cost.

  15. Triticale biotic stresses--an overview.

    PubMed

    Arseniuk, Edward

    2014-01-01

    Triticale has been considered as resistant to diseases over a long time. Although, many authors perpetuate this opinion, it is no longer true. However, in comparison to wheat and rye triticale still may look as a healthy crop, but its healthiness has been steadily declining. It could be explained by steady expansion of the growing area and longer exposure to pathogens. On the other hand, triticale is a crop on which meet pathogens of wheat and rye, but there is evidence that on triticale embedded more so called "wheat pathogens", than rye ones. For such an notable example may serve races of Puccinia recondita. In the latter respect triticale also appears to be a bridge facilitating a direct contact between the pathogens, e.g. between physiological forms of the most important cereal rusts. Such contacts stimulate somatic hybridization on bridging triticale plant and may finally result in new hybrid pathotypes carrying virulence genes (factors) to all three hosts, i.e. triticale, wheat and rye. In addition to all triticale commercial and agronomical values, triticale still is and it will continue to be bridging transfers of resistance genes to various pathogens and pests mainly from rye to wheat. The paper will describe main diseases affecting triticale worldwide. The first disease which occurred on this cereal in epidemic proportions was stem rust (Pucinia graminis f. sp. tritici) in Australia. Leaf and stripe rusts (P. recondita f. sp. tritici and P. striiformis) are also have gained in importance everywhere triticale is grown. In recent years, at least in Poland, powdery mildew caused by Blumeria graminis occurred in epidemic proportions in quite a number of winter triticale cultivars. Similar phenomenon has been observed with quite a number of other diseases caused by facultative pathogens, such as the most damaging to triticale the Stagonospora spp. leaf and glume blotch disease complex and other pathogens like Cochliobolus sativus, Fusarium culmorum, and F

  16. Exercise-induced asthma: an overview.

    PubMed

    Cummiskey, J

    2001-10-01

    Asthmatic attack in exercise-induced asthma is brought about by hyperventilation (not necessarily to exercise), cold air, and low humidity of the air breathed. The effects are an increase in airway resistance, damage to bronchial mucosa, and an increase in bronchovascular permeability. The mechanism of these changes is the release of mediators such as histamine, leukotrienes, nitric oxide, sensory neuropeptides, the inhibition of neuronal activity, and bronchovascular permeability. The cause of asthma and exercise-induced asthma is unknown. It is probably an abnormality of vascular control in the peribronchium and/or an alteration in local adrenergic function. The importance of exercise-induced asthma definition and the use of stimulants in sport and antidoping in sport are discussed. PMID:11678516

  17. An overview of modal-based damage identification methods

    SciTech Connect

    Farrar, C.R.; Doebling, S.W.

    1997-09-01

    This paper provides an overview of methods that examine changes in measured vibration response to detect, locate, and characterize damage in structural and mechanical systems. The basic idea behind this technology is that modal parameters (notably frequencies, mode shapes, and modal damping) are functions of the physical properties of the structure (mass, damping, and stiffness). Therefore, changes in the physical properties will cause detectable changes in the modal properties. The motivation for the development of this technology is first provided. The methods are then categorized according to various criteria such as the level of damage detection provided, model-based vs. non-model-based methods and linear vs. nonlinear methods. This overview is limited to methods that can be adapted to a wide range of structures (i.e., are not dependent on a particular assumed model form for the system such as beam-bending behavior and methods and that are not based on updating finite element models). Next, the methods are described in general terms including difficulties associated with their implementation and their fidelity. Past, current and future-planned applications of this technology to actual engineering systems are summarized. The paper concludes with a discussion of critical issues for future research in the area of modal-based damage identification.

  18. Praxis: The programming language: An advanced overview

    SciTech Connect

    Greenwood, J.R.; Holloway, F.W.; Morgan, C.R.; Evans, A. Jr.

    1987-08-06

    Praxis is an Ada-like programming language developed for efficient programming of embedded control and systems applications. It is strongly typed, and block structured in the tradition of Pascal and Ada, with efficiency and control similar to C. Praxis supports the development of systems composed of separately compiled modules, user defined data types, exception handling, and detailed data storage and control mechanisms. Direct access to machine facilities, efficient bit manipulation, and interlocked critical regions are also provided in Praxis. Praxis has been in operational use since late 1980, and current implementations for the VAX, PDP and LSI-11 computers have been released into the public domain.

  19. Pathogenesis of Chronic Urticaria: An Overview

    PubMed Central

    Jain, Sanjiv

    2014-01-01

    The pathogenesis of chronic urticaria is not well delineated and the treatment is palliative as it is not tied to the pathomechanism. The centrality of mast cells and their inappropriate activation and degranulation as the key pathophysiological event are well established. The triggering stimuli and the complexity of effector mechanisms remain speculative. Autoimmune origin of chronic urticaria, albeit controversial, is well documented. Numerical and behavioral alterations in basophils accompanied by changes in signaling molecule expression and function as well as aberrant activation of extrinsic pathway of coagulation are other alternative hypotheses. It is also probable that mast cells are involved in the pathogenesis through mechanisms that extend beyond high affinity IgE receptor stimulation. An increasing recognition of chronic urticaria as an immune mediated inflammatory disorder related to altered cytokine-chemokine network consequent to immune dysregulation resulting from disturbed innate immunity is emerging as yet another pathogenic explanation. It is likely that these different pathomechanisms are interlinked rather than independent cascades, acting either synergistically or sequentially to produce clinical expression of chronic urticaria. Insights into the complexities of pathogenesis may provide an impetus to develop safer, efficacious, and targeted immunomodulators and biological treatment for severe, refractory chronic urticaria. PMID:25120565

  20. An Overview of Emerging Immunotargets of Genitourinary Tumors.

    PubMed

    Montironi, Rodolfo; Santoni, Matteo; Cheng, Liang; Lopez-Beltran, Antonio; Massari, Francesco; Matrana, Marc R; Moch, Holger; Scarpelli, Marina

    2016-01-01

    Emerging immunotherapies targeting immune checkpoints and tumor associated antigens are leading to important clinical advances and providing a new weapon in patients with prostate (PCa) and bladder cancer (BC) and, in particular, with renal cell carcinoma (RCC). The possibility to integrate these agents in the current therapeutic scenario or genitourinary tumors, both in sequential or combined approaches, relies on a more profound comprehension of the protumorigenic activity of the immune system and of the mechanisms of cancer-related immunosuppression. In this regards, neutrophils, T and B lymphocytes and tumor-associated macrophages (TAMs) are implicated in the pathogenesis, progression and development of drug resistance in genitourinary tumors. This review is an overview on the recent insights concerning the role of immune cells in this context. PMID:26648079

  1. An overview of recent patents on musculoskeletal interface tissue engineering.

    PubMed

    Rao, Rohit T; Browe, Daniel P; Lowe, Christopher J; Freeman, Joseph W

    2016-02-01

    Interface tissue engineering involves the development of engineered grafts that promote integration between multiple tissue types. Musculoskeletal tissue interfaces are critical to the safe and efficient transmission of mechanical forces between multiple musculoskeletal tissues, e.g., between ligament and bone tissue. However, these interfaces often do not physiologically regenerate upon injury, resulting in impaired tissue function. Therefore, interface tissue engineering approaches are considered to be particularly relevant for the structural restoration of musculoskeletal tissues interfaces. In this article, we provide an overview of the various strategies used for engineering musculoskeletal tissue interfaces with a specific focus on the recent important patents that have been issued for inventions that were specifically designed for engineering musculoskeletal interfaces as well as those that show promise to be adapted for this purpose. PMID:26577344

  2. An overview of instrumentation capabilities for Scientific ballooning in India

    NASA Astrophysics Data System (ADS)

    Devarajan, Anand; Reddy Vizapur, Anmi; Rao Tanneeru, Venkateswara; Bangaru, Kapardhi; Trivedi, Dharmesh; Rodi, Ashish; Ojha, Devendra; Koli, Santosh

    2016-07-01

    The Balloon Facility of Tata Institute of Fundamental Research (TIFR-BF) in India, launches scientific balloons for research in the field of astronomy, astrobiology and atmospheric sciences. TIFR-BF not only has the capability to design, fabricate and launch zero-pressure balloons, but also provide operational and engineering support for launching them. The Control Instrumentation Group (CIG) at the balloon facility handles all electronics related to telemetry, telecommand, tracking, real-time data display, data storage, air-safety and payload recovery. In the recent past, it has designed and developed customized electronics and payload orientation mechanism to meet specific experimental objectives. Small, inexpensive and rugged industrial grade radio data modems were successfully deployed in balloon flights for low bit rate data and image telemetry. This paper will provide an overview and in-flight performance of some of the recent developments in instrumentation and electronics systems. Our plans for future upgradations will also be discussed.

  3. An Overview of Bayesian Methods for Neural Spike Train Analysis

    PubMed Central

    2013-01-01

    Neural spike train analysis is an important task in computational neuroscience which aims to understand neural mechanisms and gain insights into neural circuits. With the advancement of multielectrode recording and imaging technologies, it has become increasingly demanding to develop statistical tools for analyzing large neuronal ensemble spike activity. Here we present a tutorial overview of Bayesian methods and their representative applications in neural spike train analysis, at both single neuron and population levels. On the theoretical side, we focus on various approximate Bayesian inference techniques as applied to latent state and parameter estimation. On the application side, the topics include spike sorting, tuning curve estimation, neural encoding and decoding, deconvolution of spike trains from calcium imaging signals, and inference of neuronal functional connectivity and synchrony. Some research challenges and opportunities for neural spike train analysis are discussed. PMID:24348527

  4. Formal Methods at Intel - An Overview

    NASA Technical Reports Server (NTRS)

    Harrison, John

    2010-01-01

    Since the 1990s, Intel has invested heavily in formal methods, which are now deployed in several domains: hardware, software, firmware, protocols etc. Many different formal methods tools and techniques are in active use, including symbolic trajectory evaluation, temporal logic model checking, SMT-style combined decision procedures, and interactive higher-order logic theorem proving. I will try to give a broad overview of some of the formal methods activities taking place at Intel, and describe the challenges of extending formal verification to new areas and of effectively using multiple formal techniques in combination

  5. Flood adaptive traits and processes: an overview.

    PubMed

    Voesenek, Laurentius A C J; Bailey-Serres, Julia

    2015-04-01

    Unanticipated flooding challenges plant growth and fitness in natural and agricultural ecosystems. Here we describe mechanisms of developmental plasticity and metabolic modulation that underpin adaptive traits and acclimation responses to waterlogging of root systems and submergence of aerial tissues. This includes insights into processes that enhance ventilation of submerged organs. At the intersection between metabolism and growth, submergence survival strategies have evolved involving an ethylene-driven and gibberellin-enhanced module that regulates growth of submerged organs. Opposing regulation of this pathway is facilitated by a subgroup of ethylene-response transcription factors (ERFs), which include members that require low O₂ or low nitric oxide (NO) conditions for their stabilization. These transcription factors control genes encoding enzymes required for anaerobic metabolism as well as proteins that fine-tune their function in transcription and turnover. Other mechanisms that control metabolism and growth at seed, seedling and mature stages under flooding conditions are reviewed, as well as findings demonstrating that true endurance of submergence includes an ability to restore growth following the deluge. Finally, we highlight molecular insights obtained from natural variation of domesticated and wild species that occupy different hydrological niches, emphasizing the value of understanding natural flooding survival strategies in efforts to stabilize crop yields in flood-prone environments. PMID:25580769

  6. White spot syndrome virus: an overview on an emergent concern

    PubMed Central

    Sánchez-Paz, Arturo

    2010-01-01

    Viruses are ubiquitous and extremely abundant in the marine environment. One of such marine viruses, the white spot syndrome virus (WSSV), has emerged globally as one of the most prevalent, widespread and lethal for shrimp populations. However, at present there is no treatment available to interfere with the unrestrained occurrence and spread of the disease. The recent progress in molecular biology techniques has made it possible to obtain information on the factors, mechanisms and strategies used by this virus to infect and replicate in susceptible host cells. Yet, further research is still required to fully understand the basic nature of WSSV, its exact life cycle and mode of infection. This information will expand our knowledge and may contribute to developing effective prophylactic or therapeutic measures. This review provides a state-of-the-art overview of the topic, and emphasizes the current progress and future direction for the development of WSSV control strategies. PMID:20181325

  7. An Overview of the Glass Transition Temperature of Synthetic Polymers.

    ERIC Educational Resources Information Center

    Beck, Keith R.; And Others

    1984-01-01

    Presents an overview of the glass-to-rubber transition, what it is, why it is important, and the major factors that influence it. Indicates that this information should be incorporated into chemistry curricula. (JN)

  8. An Overview of the Human Systems Integration Division

    NASA Technical Reports Server (NTRS)

    Gore, Brian F.

    2015-01-01

    This presentation will provide an overview of the Human Systems Integration Division, and will highlight some of the human performance modeling efforts undertaken in previously presented MIDAS human performance modeling efforts.

  9. An Overview Of Current Research At The Environmental Protection Agency

    EPA Science Inventory

    The purpose of this presentation is to provide an overview of the current research at the Environmental Protection Agency. FOR FURTHER INFORMATION, CONTACT ROGER B. YEARDLEY, JR., LAND REMEDIATION AND POLLUTION CONTROL DIVISION, 513-569-7548.

  10. OVERVIEW, LOOKING SOUTHWEST, TO 8750 PIT WITH DRILL SETTING AN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERVIEW, LOOKING SOUTHWEST, TO 8750 PIT WITH DRILL SETTING AN EXPLOSIVE CHARGE TO REMOVE OVERBURDEN AND ACCESS COAL SEAMS LOCATED 200 FEET BELOW FOR STRIPPING. - Drummond Coal Company Cedrum Mine, 8750 Pit, County Road 124, Townley, Walker County, AL

  11. ANS severe accident program overview & planning document

    SciTech Connect

    Taleyarkhan, R.P.

    1995-09-01

    The Advanced Neutron Source (ANS) severe accident document was developed to provide a concise and coherent mechanism for presenting the ANS SAP goals, a strategy satisfying these goals, a succinct summary of the work done to date, and what needs to be done in the future to ensure timely licensability. Guidance was received from various bodies [viz., panel members of the ANS severe accident workshop and safety review committee, Department of Energy (DOE) orders, Nuclear Regulatory Commission (NRC) requirements for ALWRs and advanced reactors, ACRS comments, world-wide trends] were utilized to set up the ANS-relevant SAS goals and strategy. An in-containment worker protection goal was also set up to account for the routine experimenters and other workers within containment. The strategy for achieving the goals is centered upon closing the severe accident issues that have the potential for becoming certification issues when assessed against realistic bounding events. Realistic bounding events are defined as events with an occurrency frequency greater than 10{sup {minus}6}/y. Currently, based upon the level-1 probabilistic risk assessment studies, the realistic bounding events for application for issue closure are flow blockage of fuel element coolant channels, and rapid depressurization-related accidents.

  12. The East Asian summer monsoon: an overview

    NASA Astrophysics Data System (ADS)

    Yihui, Ding; Chan, Johnny C. L.

    2005-06-01

    The present paper provides an overview of major problems of the East Asian summer monsoon. The summer monsoon system over East Asia (including the South China Sea (SCS)) cannot be just thought of as the eastward and northward extension of the Indian monsoon. Numerous studies have well documented that the huge Asian summer monsoon system can be divided into two subsystems: the Indian and the East Asian monsoon system which are to a greater extent independent of each other and, at the same time, interact with each other. In this context, the major findings made in recent two decades are summarized below: (1) The earliest onset of the Asian summer monsoon occurs in most of cases in the central and southern Indochina Peninsula. The onset is preceded by development of a BOB (Bay of Bengal) cyclone, the rapid acceleration of low-level westerlies and significant increase of convective activity in both areal extent and intensity in the tropical East Indian Ocean and the Bay of Bengal. (2) The seasonal march of the East Asian summer monsoon displays a distinct stepwise northward and northeastward advance, with two abrupt northward jumps and three stationary periods. The monsoon rain commences over the region from the Indochina Peninsula-the SCS-Philippines during the period from early May to mid-May, then it extends abruptly to the Yangtze River Basin, and western and southern Japan, and the southwestern Philippine Sea in early to mid-June and finally penetrates to North China, Korea and part of Japan, and the topical western West Pacific. (3) After the onset of the Asian summer monsoon, the moisture transport coming from Indochina Peninsula and the South China Sea plays a crucial “switch” role in moisture supply for precipitation in East Asia, thus leading to a dramatic change in climate regime in East Asia and even more remote areas through teleconnection. (4) The East Asian summer monsoon and related seasonal rain belts assumes significant variability at

  13. Radiation Diffusion:. AN Overview of Physical and Numerical Concepts

    NASA Astrophysics Data System (ADS)

    Graziani, Frank

    2005-12-01

    An overview of the physical and mathematical foundations of radiation transport is given. Emphasis is placed on how the diffusion approximation and its transport corrections arise. An overview of the numerical handling of radiation diffusion coupled to matter is also given. Discussions center on partial temperature and grey methods with comments concerning fully implicit methods. In addition finite difference, finite element and Pert representations of the div-grad operator is also discussed

  14. Etiology and pathogenesis of oral lichen planus: an overview.

    PubMed

    Kurago, Zoya B

    2016-07-01

    Oral lichen planus is a noninfectious, chronic inflammatory condition that involves the oral mucosal stratified squamous epithelium and the underlying lamina propria and may be accompanied by skin lesions. This overview describes the current understanding of the immunopathologic mechanisms implicated in oral lichen planus. PMID:27260276

  15. An overview of statin-associated proteinuria.

    PubMed

    Tiwari, Atul

    2006-05-01

    Statins are an established therapeutic modality for the treatment of hypercholesterolemia. Although they generally exhibit a good efficacy and tolerability profile, their reputation has been tarnished as a result of reports of myotoxicity and, more recently, observations of proteinuria. The increased incidence of proteinuria with rosuvastatin was of particular concern, and raised questions about the renoprotective actions of statins. Different hypotheses have been put forward to explain the mechanisms of statin-induced proteinuria. The multifarious effects of statins, independent of their effects on cholesterol-lowering, form the basis of such hypotheses. However, rosuvastatin-associated proteinuria is transient and reversible and even at the highest dose did not affect renal function after prolonged treatment. It would appear that clinically relevant proteinuria is not associated solely with rosuvastatin and might represent a minor class effect of statins with a fairly low incidence. However, definitive proof of this assertion will need to be provided by rigorous testing. PMID:16635810

  16. An Overview of Biological Macromolecule Crystallization

    PubMed Central

    Krauss, Irene Russo; Merlino, Antonello; Vergara, Alessandro; Sica, Filomena

    2013-01-01

    The elucidation of the three dimensional structure of biological macromolecules has provided an important contribution to our current understanding of many basic mechanisms involved in life processes. This enormous impact largely results from the ability of X-ray crystallography to provide accurate structural details at atomic resolution that are a prerequisite for a deeper insight on the way in which bio-macromolecules interact with each other to build up supramolecular nano-machines capable of performing specialized biological functions. With the advent of high-energy synchrotron sources and the development of sophisticated software to solve X-ray and neutron crystal structures of large molecules, the crystallization step has become even more the bottleneck of a successful structure determination. This review introduces the general aspects of protein crystallization, summarizes conventional and innovative crystallization methods and focuses on the new strategies utilized to improve the success rate of experiments and increase crystal diffraction quality. PMID:23727935

  17. An overview of biological macromolecule crystallization.

    PubMed

    Russo Krauss, Irene; Merlino, Antonello; Vergara, Alessandro; Sica, Filomena

    2013-01-01

    The elucidation of the three dimensional structure of biological macromolecules has provided an important contribution to our current understanding of many basic mechanisms involved in life processes. This enormous impact largely results from the ability of X-ray crystallography to provide accurate structural details at atomic resolution that are a prerequisite for a deeper insight on the way in which bio-macromolecules interact with each other to build up supramolecular nano-machines capable of performing specialized biological functions. With the advent of high-energy synchrotron sources and the development of sophisticated software to solve X-ray and neutron crystal structures of large molecules, the crystallization step has become even more the bottleneck of a successful structure determination. This review introduces the general aspects of protein crystallization, summarizes conventional and innovative crystallization methods and focuses on the new strategies utilized to improve the success rate of experiments and increase crystal diffraction quality. PMID:23727935

  18. An overview of the Charcot foot pathophysiology

    PubMed Central

    Kaynak, Gökhan; Birsel, Olgar; Güven, Mehmet Fatih; Öğüt, Tahir

    2013-01-01

    Charcot arthropathy of the foot is a rare but devastating complication of diabetes that remains to be a challenging issue for the foot and ankle surgeons. Charcot foot fails to be an obvious diagnostic option that comes to mind, even in a pathognomonic clinical appearance. The rarity of the disorder, more common pathologies that mimic the condition, and the self-limiting prognosis deviate the clinician from the right diagnosis. The clinical challenges in the diagnosis of Charcot foot require in-depth investigations of its enigmatic nature to establish useful guidelines. Yet, this goal seems to be beyond reach, without a holistic view of the immense literature concerning the pathophysiology of the disorder. The primary objective of this article is to put together and review the recent advancements about the etiology and intrinsic mechanisms of diabetic Charcot foot. PMID:23919113

  19. Psychiatric aspects of phosphodiesterases: An overview

    PubMed Central

    Murthy, Vasantmeghna S.; Mangot, Ajish G.

    2015-01-01

    Phosphodiesterases (PDE) are exciting new targets in medical sciences. These enzymes are some of the key mediators of cellular functions in the body and hence are attractive sites for drug-induced modulations. With the finding that Tofisopam, a new anxiolytic, inhibits PDEs, the authors were inspired to look into the role of PDE and drugs acting on them in psychiatry. Hence, the review was undertaken. We found several research materials available highlighting the role of PDE in cellular functions and the possible newer etiological mechanisms of neuropsychiatric illnesses such as schizophrenia, depression/anxiety disorders, and cognitive dysfunction involving PDEs. We also found that there are many molecules acting on PDEs, which have the potential to alter the way we treat mental illnesses today. This article is intended to provide an in-depth look at these enzymes so that more cost-effective therapeutic molecules may be synthesized and marketed in India for managing mental illnesses. PMID:26729948

  20. Veterinary clinical nutrition: success stories: an overview.

    PubMed

    Davies, Mike

    2016-08-01

    In this overview of success stories in veterinary clinical nutrition topics in cats and dogs reviewed include the dietary management of chronic kidney disease, dissolution of urinary tract uroliths by dietary modification, the recognition that taurine and L-carnitine deficiencies can cause dilated cardiomyopathy; that clinical signs associated with feline hyperthyroidism (caused by a benign adenoma) can be controlled by a low-iodine diet alone; that dietary management of canine osteoarthritis can also reduce non-steroidal anti-inflammatory drug doses; and that disease-free intervals and survival times can be statistically longer in dogs with Stage III lymphoma managed with diet. As we discover more about nutrigenetics and nutrigenomics, and as we expand our basic understanding of idiopathic diseases we are bound to identify more nutritionally related causes, and be able to develop novel dietary strategies to manage disease processes, including the formulation of diets designed to alter gene expression to obtain beneficial clinical outcomes. PMID:27269202

  1. Poly Cystic Ovarian Syndrome: An Updated Overview

    PubMed Central

    El Hayek, Samer; Bitar, Lynn; Hamdar, Layal H.; Mirza, Fadi G.; Daoud, Georges

    2016-01-01

    Poly Cystic Ovarian Syndrome (PCOS) is one of the most common metabolic and reproductive disorders among women of reproductive age. Women suffering from PCOS present with a constellation of symptoms associated with menstrual dysfunction and androgen excess, which significantly impacts their quality of life. They may be at increased risk of multiple morbidities, including obesity, insulin resistance, type II diabetes mellitus, cardiovascular disease (CVD), infertility, cancer, and psychological disorders. This review summarizes what the literature has so far provided from guidelines to diagnosis of PCOS. It will also present a general overview about the morbidities associated with this disease, specifically with its more severe classic form. Finally, the review will stress on the various aspects of treatment and screening recommendations currently used in the management of this condition. PMID:27092084

  2. Gamma-Ray Bursts: An Overview

    NASA Technical Reports Server (NTRS)

    Fishman, Gerald J.

    1995-01-01

    A history and overview of the observed properties of gamma-ray bursts are presented. The phenomenon of gamma-ray bursts is without precedent in astronomy, having no observed property that would be a direct indicator of their distance and no counterpart object in another wavelength region. Their brief, random appearance only in the gamma-ray region has made their study difficult. The observed time profiles, spectral properties, and durations of gamma-ray bursts cover a wide range. All proposed models for their origin must be considered speculative. It is humbling to think that even after 25 years since their discovery, the distance scale of gamma-ray bursts is still very much debatable.

  3. Space Environment Effects on Materials : An Overview

    NASA Technical Reports Server (NTRS)

    Garrett, Henry B.

    2006-01-01

    A general overview on the space environment and its effects on materials is presented. The topics include: 1) Impact of Space Effects on Spacecraft Costs; 2) Space Environment Effects on Spacecraft by Source; 3) Primary Source of Space Effects: The Sun; 4) The Earth's Environment; 5) Trapped Radiation Belts; 6) Aurora Are Everywhere; 7) Spacecraft Interactions; 8) Atmospheric Effects; 9) Contaminant Effects on Materials; 10) Meteoroid/Debris Effects on Materials; 11) Spacecraft Surface Charging; 12) Surface Discharge Effects; 13) Internal Electrostatic Discharge--Satellite Killer; 14) Plasma Interactions DS-1 Ion Engines; 15) Radiation Effects on Spacecraft Systems and Materials; 16) Total Ionizing Dose Effects Total Ionizing Dose Effects; 17) Man-Made Sources of Space Effects Man-Made Sources of Space Effects; and 18) Space Environments Versus Interactions.

  4. Poly Cystic Ovarian Syndrome: An Updated Overview.

    PubMed

    El Hayek, Samer; Bitar, Lynn; Hamdar, Layal H; Mirza, Fadi G; Daoud, Georges

    2016-01-01

    Poly Cystic Ovarian Syndrome (PCOS) is one of the most common metabolic and reproductive disorders among women of reproductive age. Women suffering from PCOS present with a constellation of symptoms associated with menstrual dysfunction and androgen excess, which significantly impacts their quality of life. They may be at increased risk of multiple morbidities, including obesity, insulin resistance, type II diabetes mellitus, cardiovascular disease (CVD), infertility, cancer, and psychological disorders. This review summarizes what the literature has so far provided from guidelines to diagnosis of PCOS. It will also present a general overview about the morbidities associated with this disease, specifically with its more severe classic form. Finally, the review will stress on the various aspects of treatment and screening recommendations currently used in the management of this condition. PMID:27092084

  5. An Overview of Stationary Fuel Cell Technology

    SciTech Connect

    DR Brown; R Jones

    1999-03-23

    Technology developments occurring in the past few years have resulted in the initial commercialization of phosphoric acid (PA) fuel cells. Ongoing research and development (R and D) promises further improvement in PA fuel cell technology, as well as the development of proton exchange membrane (PEM), molten carbonate (MC), and solid oxide (SO) fuel cell technologies. In the long run, this collection of fuel cell options will be able to serve a wide range of electric power and cogeneration applications. A fuel cell converts the chemical energy of a fuel into electrical energy without the use of a thermal cycle or rotating equipment. In contrast, most electrical generating devices (e.g., steam and gas turbine cycles, reciprocating engines) first convert chemical energy into thermal energy and then mechanical energy before finally generating electricity. Like a battery, a fuel cell is an electrochemical device, but there are important differences. Batteries store chemical energy and convert it into electrical energy on demand, until the chemical energy has been depleted. Depleted secondary batteries may be recharged by applying an external power source, while depleted primary batteries must be replaced. Fuel cells, on the other hand, will operate continuously, as long as they are externally supplied with a fuel and an oxidant.

  6. [People with learning disabilities: an overview of the facts].

    PubMed

    Schipper, Karen

    2014-01-01

    This article gives a short overview of some basic facts about people with learning disabilities. The prevalence (1-3% worldwide) and stability of the incidence are described, as well as the causes and possible medical comorbidities.- People with learning disabilities are at significantly greater risk of developing cognitive and medical problems compared with the average population. Lastly, an overview of actual chronic care costs is given, as well as actual participation possibilities for people with learning disabilities. PMID:25534270

  7. Cholera Epidemiology in Nigeria: an overview

    PubMed Central

    Adagbada, Ajoke Olutola; Adesida, Solayide Abosede; Nwaokorie, Francisca Obiageri; Niemogha, Mary-Theresa; Coker, Akitoye Olusegun

    2012-01-01

    Cholera is an acute diarrhoeal infection caused by ingestion of food or water contaminated with the bacterium, Vibrio cholera. Choleragenic V. cholera O1 and O139 are the only causative agents of the disease. The two most distinguishing epidemiologic features of the disease are its tendency to appear in explosive outbreaks and its predisposition to causing pandemics that may progressively affect many countries and spread into continents. Despite efforts to control cholera, the disease continues to occur as a major public health problem in many developing countries. Numerous studies over more than a century have made advances in the understanding of the disease and ways of treating patients, but the mechanism of emergence of new epidemic strains, and the ecosystem supporting regular epidemics, remain challenging to epidemiologists. In Nigeria, since the first appearance of epidemic cholera in 1972, intermittent outbreaks have been occurring. The later part of 2010 was marked with severe outbreak which started from the northern part of Nigeria, spreading to the other parts and involving approximately 3,000 cases and 781 deaths. Sporadic cases have also been reported. Although epidemiologic surveillance constitutes an important component of the public health response, publicly available surveillance data from Nigeria have been relatively limited to date. Based on existing relevant scientific literature on features of cholera, this paper presents a synopsis of cholera epidemiology emphasising the situation in Nigeria. PMID:22937199

  8. Bioavailability enhancers of herbal origin: an overview.

    PubMed

    Kesarwani, Kritika; Gupta, Rajiv; Mukerjee, Alok

    2013-04-01

    Recently, the use of herbal medicines has been increased all over the world due to their therapeutic effects and fewer adverse effects as compared to the modern medicines. However, many herbal drugs and herbal extracts despite of their impressive in-vitro findings demonstrates less or negligible in-vivo activity due to their poor lipid solubility or improper molecular size, resulting in poor absorption and hence poor bioavailability. Nowadays with the advancement in the technology, novel drug delivery systems open the door towards the development of enhancing bioavailability of herbal drug delivery systems. For last one decade many novel carriers such as liposomes, microspheres, nanoparticles, transferosomes, ethosomes, lipid based systems etc. have been reported for successful modified delivery of various herbal drugs. Many herbal compounds including quercetin, genistein, naringin, sinomenine, piperine, glycyrrhizin and nitrile glycoside have demonstrated capability to enhance the bioavailability. The objective of this review is to summarize various available novel drug delivery technologies which have been developed for delivery of drugs (herbal), and to achieve better therapeutic response. An attempt has also been made to compile a profile on bioavailability enhancers of herbal origin with the mechanism of action (wherever reported) and studies on improvement in drug bioavailability, exhibited particularly by natural compounds. PMID:23620848

  9. Organ repair and regeneration: an overview.

    PubMed

    Baddour, Joëlle A; Sousounis, Konstantinos; Tsonis, Panagiotis A

    2012-03-01

    A number of organs have the intrinsic ability to regenerate, a distinctive feature that varies among organisms. Organ regeneration is a process not fully yet understood. However, when its underlying mechanisms are unraveled, it holds tremendous therapeutic potential for humans. In this review, we chose to summarize the repair and regenerative potential of the following organs and organ systems: thymus, adrenal gland, thyroid gland, intestine, lungs, heart, liver, blood vessels, germ cells, nervous system, eye tissues, hair cells, kidney and bladder, skin, hair follicles, pancreas, bone, and cartilage. For each organ, a review of the following is presented: (a) factors, pathways, and cells that are involved in the organ's intrinsic regenerative ability, (b) contribution of exogenous cells - such as progenitor cells, embryonic stem cells, induced pluripotent stem cells, and bone marrow-, adipose- and umbilical cord blood-derived stem cells - in repairing and regenerating organs in the absence of an innate intrinsic regenerative capability, (c) and the progress made in engineering bio-artificial scaffolds, tissues, and organs. Organ regeneration is a promising therapy that can alleviate humans from diseases that have not been yet cured. It is also superior to already existing treatments that utilize exogenous sources to substitute for the organ's lost structure and/or function(s). PMID:22457174

  10. Bioavailability enhancers of herbal origin: An overview

    PubMed Central

    Kesarwani, Kritika; Gupta, Rajiv

    2013-01-01

    Recently, the use of herbal medicines has been increased all over the world due to their therapeutic effects and fewer adverse effects as compared to the modern medicines. However, many herbal drugs and herbal extracts despite of their impressive in-vitro findings demonstrates less or negligible in-vivo activity due to their poor lipid solubility or improper molecular size, resulting in poor absorption and hence poor bioavailability. Nowadays with the advancement in the technology, novel drug delivery systems open the door towards the development of enhancing bioavailability of herbal drug delivery systems. For last one decade many novel carriers such as liposomes, microspheres, nanoparticles, transferosomes, ethosomes, lipid based systems etc. have been reported for successful modified delivery of various herbal drugs. Many herbal compounds including quercetin, genistein, naringin, sinomenine, piperine, glycyrrhizin and nitrile glycoside have demonstrated capability to enhance the bioavailability. The objective of this review is to summarize various available novel drug delivery technologies which have been developed for delivery of drugs (herbal), and to achieve better therapeutic response. An attempt has also been made to compile a profile on bioavailability enhancers of herbal origin with the mechanism of action (wherever reported) and studies on improvement in drug bioavailability, exhibited particularly by natural compounds. PMID:23620848

  11. Olfaction and gustation in fish: an overview.

    PubMed

    Hara, T J

    1994-10-01

    Living in an aquatic environment, often devoid of light but rich in dissolved compounds, fish have highly developed chemosensory and chemical signalling systems. The olfactory and gustatory systems comprise the major chemosensory pathways. Despite considerable variations in structural organization of the peripheral olfactory organ throughout fish species, ultrastructural organization of the olfactory sensory epithelium is extremely consistent. The olfactory receptor cell is a bipolar neurone which is directly exposed to the external environment and sends information to the brain by its own axon (cranial nerve I). Four major classes of chemicals have been identified as specific olfactory stimuli and their stimulatory effectiveness characterized: amino acids, sex steroids, bile acids/salts and prostaglandins. Olfactory signals such as those involved in reproduction and feeding may be processed independently through two distinct subsystems: the lateral and medial olfactory systems. The taste buds constitute the structural basis of the gustatory organ. Taste buds may occur not only in the oropharyngeal cavity, but on the whole body surface. Chemical information detected by specialized epithelial cells, gustatory cells, is transmitted to the central nervous system by cranial nerve VII (facial), IX (glossopharyngeal), and X (vagal). Besides diverse sensitivities and specificities for amino acids, fish gustatory receptors detect various organic acids, nucleotides and bile salts. Putative receptors, molecular mechanisms of transduction and the role played by olfaction and gustation in feeding, reproduction, migration and other fish behaviours are discussed. PMID:7839864

  12. Multi-finger Prehension: An overview

    PubMed Central

    Zatsiorsky, Vladimir M.; Latash, Mark L.

    2009-01-01

    This paper reviews the available experimental evidence on what people do when they grasp an object with several digits and then manipulate it. In addition to the Introduction, the paper includes three parts each addressing a specific aspect of multi-finger prehension. Part II discusses manipulation forces, i.e. the resultant force and moment of force exerted on the object, and the digits contribution to such force production. Part III deals with internal forces defined as forces that cancel each other and do not disturb object equilibrium. The role of the internal forces in maintaining the object stability is discussed with respect to such issues as slip prevention, tilt prevention and resistance to perturbations. Part IV is devoted to the motor control of prehension. It covers such topics as prehension synergies, chain effects, the principle of superposition, inter-finger connection matrices and reconstruction of neural commands, mechanical advantage of the fingers, and the simultaneous digit adjustment to several mutually reinforcing or conflicting demands. PMID:18782719

  13. An Overview of an Experimental Demonstration Aerotow Program

    NASA Technical Reports Server (NTRS)

    Murray, James E.; Bowers, Albion H.; Lokos, William A.; Peters, Todd L.; Gera, Joseph

    1998-01-01

    An overview of an experimental demonstration of aerotowing a delta-wing airplane with low-aspect ratio and relatively high wing loading is presented. Aerotowing of future space launch configurations is a new concept, and the objective of the work described herein is to demonstrate the aerotow operation using an airplane configuration similar to conceptual space launch vehicles. Background information on the use of aerotow for a space launch vehicle is presented, and the aerotow system used in this demonstration is described. The ground tests, analytical studies, and flight planning used to predict system behavior and to enhance flight safety are detailed. The instrumentation suite and flight test maneuvers flown are discussed, preliminary performance is assessed, and flight test results are compared with the preflight predictions.

  14. In silico gene expression analysis – an overview

    PubMed Central

    Murray, David; Doran, Peter; MacMathuna, Padraic; Moss, Alan C

    2007-01-01

    Efforts aimed at deciphering the molecular basis of complex disease are underpinned by the availability of high throughput strategies for the identification of biomolecules that drive the disease process. The completion of the human genome-sequencing project, coupled to major technological developments, has afforded investigators myriad opportunities for multidimensional analysis of biological systems. Nowhere has this research explosion been more evident than in the field of transcriptomics. Affordable access and availability to the technology that supports such investigations has led to a significant increase in the amount of data generated. As most biological distinctions are now observed at a genomic level, a large amount of expression information is now openly available via public databases. Furthermore, numerous computational based methods have been developed to harness the power of these data. In this review we provide a brief overview of in silico methodologies for the analysis of differential gene expression such as Serial Analysis of Gene Expression and Digital Differential Display. The performance of these strategies, at both an operational and result/output level is assessed and compared. The key considerations that must be made when completing an in silico expression analysis are also presented as a roadmap to facilitate biologists. Furthermore, to highlight the importance of these in silico methodologies in contemporary biomedical research, examples of current studies using these approaches are discussed. The overriding goal of this review is to present the scientific community with a critical overview of these strategies, so that they can be effectively added to the tool box of biomedical researchers focused on identifying the molecular mechanisms of disease. PMID:17683638

  15. Automotive shredder residue (ASR) management: An overview.

    PubMed

    Cossu, R; Lai, T

    2015-11-01

    On the basis of statistical data, approximately 6.5 million tons of ELVs were produced in Europe in 2011. ELVs are processed according to a treatment scheme comprising three main phases: depollution, dismantling and shredding. The ferrous fraction represents about 70-75% of the total shredded output, while nonferrous metals represent about 5%. The remaining 20-25% is referred to as automotive shredder residue (ASR). ASR is largely landfilled due to its heterogeneous and complex matrix. With a start date of January 1st 2015, the European Directive 2000/53/EC establishes the reuse and recovery of a minimum of 95% ELV total weight. To reach these targets various post-shredder technologies have been developed with the aim of improving recovery of materials and energy from ASR. In order to evaluate the environmental impacts of different management options of ELVs, the life cycle assessment (LCA) methodology has been applied taking into account the potential implication of sustainable design of vehicles and treatment of residues after shredding of ELVs. Findings obtained reveal that a combination of recycling and energy recovery is required to achieve European targets, with landfilling being viewed as the least preferred option. The aim of this work is to provide a general overview of the recent development of management of ELVs and treatment of ASR with a view to minimizing the amount of residues disposed of in landfill. PMID:26294011

  16. An overview of San Francisco Bay PORTS

    USGS Publications Warehouse

    Cheng, Ralph T.; McKinnie, David; English, Chad; Smith, Richard E.

    1998-01-01

    The Physical Oceanographic Real-Time System (PORTS) provides observations of tides, tidal currents, and meteorological conditions in real-time. The San Francisco Bay PORTS (SFPORTS) is a decision support system to facilitate safe and efficient maritime commerce. In addition to real-time observations, SFPORTS includes a nowcast numerical model forming a San Francisco Bay marine nowcast system. SFPORTS data and nowcast numerical model results are made available to users through the World Wide Web (WWW). A brief overview of SFPORTS is presented, from the data flow originated at instrument sensors to final results delivered to end users on the WWW. A user-friendly interface for SFPORTS has been designed and implemented. Appropriate field data analysis, nowcast procedures, design and generation of graphics for WWW display of field data and nowcast results are presented and discussed. Furthermore, SFPORTS is designed to support hazardous materials spill prevention and response, and to serve as resources to scientists studying the health of San Francisco Bay ecosystem. The success (or failure) of the SFPORTS to serve the intended user community is determined by the effectiveness of the user interface.

  17. Next generation sequencing methodologies--an overview.

    PubMed

    Pickrell, William O; Rees, Mark I; Chung, Seo-Kyung

    2012-01-01

    Gene discovery has been one of the most important advances in our understanding of human disorders. Early linkage and positional cloning strategies have now given way to next generation sequencing (NGS) with age-old help from biostatistical and bioinformatical input. In this chapter, we present the importance of getting the basics right, namely, how the best phenotyping in the clinical domain will provide a higher chance of a successful NGS experiment. In addition, we show getting the correct submission of DNA samples to NGS providers is dependent on the type of inheritance pattern that may or may not be apparent. We discuss one of the most crucial decisions for investigators when designing a study, namely choosing a trio, quad or cohort for analysis. Following on from this, we compare and contrast the underlying technology adopted by provider companies as they vie for customers and submissions. Each platform has advantages and disadvantages based on false calls, coverage, and read depth; however, some of these issues may be solved with the third wave of sequencing technology development in early commercial roll-out. Lastly, we provide a bioinformatic filtering overview of a "quad"-based submission and show how 3 million SNPs and indels can be reduced to a biologically plausible and experimentally manageable n≤50 gene variants. PMID:23046880

  18. An overview of STAR experimental results

    NASA Astrophysics Data System (ADS)

    Xu, Nu

    2014-11-01

    With large acceptance and excellent particle identification, STAR is one of the best mid-rapidity collider experiments for studying high-energy nuclear collisions. The STAR experiment provides full information on initial conditions, properties of the hot and dense medium as well as the properties at freeze-out. In Au+Au collisions at √{sNN} = 200 GeV, STAR's focus is on the nature of the sQGP produced at RHIC. In order to explore the properties of the QCD phase diagram, since 2010, the experiment has collected sizable data sets of Au+Au collisions at the lower collision energy region where the net-baryon density is large. At the 2014 Quark Matter Conference, the STAR experiment made 16 presentations that cover physics topics including collective dynamics, electromagnetic probes, heavy-flavor, initial state physics, jets, QCD phase diagram, thermodynamics and hadron chemistry, and future experimental facilities, upgrades, and instrumentation[1]. In this overview we will highlight a few results from the STAR experiment, especially those from the recent measurements of the RHIC beam energy scan program. At the end, instead of a summary, we will discuss STAR's near future physics programs at RHIC.

  19. Health and society in Chukotka: an overview.

    PubMed

    Dudarev, Alexey A; Chupakhin, Valery S; Odland, Jon Øyvind

    2013-01-01

    This study provides a historical overview of the changes in the socio-economic and health status of the population of Chukotka, from the Soviet to the post-Soviet period, with special attention paid to the circumstances of indigenous people. Past health studies in Chukotka are reviewed and key demographic and health indicator data presented. Since the 1990s, Chukotka's population has shrunk to a third of its former size due to emigration of non-indigenous and mostly younger people, with a corresponding increase in the mortality rate due to aging of the population. However, the indigenous population has remained stable. Among the most important causes of mortality are injuries. The living conditions of indigenous people continue to be a cause of concern, beset by high rates of poverty, unemployment, alcoholism, suicide and a variety of infectious diseases, such as tuberculosis and sexually transmitted infections. The economy, general infrastructure and health care system of Chukotka have been considerably improved by the Abramovich administration in the 2000s. PMID:23518623

  20. Health and society in Chukotka: an overview

    PubMed Central

    Dudarev, Alexey A.; Chupakhin, Valery S.; Odland, Jon Øyvind

    2013-01-01

    This study provides a historical overview of the changes in the socio-economic and health status of the population of Chukotka, from the Soviet to the post-Soviet period, with special attention paid to the circumstances of indigenous people. Past health studies in Chukotka are reviewed and key demographic and health indicator data presented. Since the 1990s, Chukotka's population has shrunk to a third of its former size due to emigration of non-indigenous and mostly younger people, with a corresponding increase in the mortality rate due to aging of the population. However, the indigenous population has remained stable. Among the most important causes of mortality are injuries. The living conditions of indigenous people continue to be a cause of concern, beset by high rates of poverty, unemployment, alcoholism, suicide and a variety of infectious diseases, such as tuberculosis and sexually transmitted infections. The economy, general infrastructure and health care system of Chukotka have been considerably improved by the Abramovich administration in the 2000s. PMID:23518623

  1. Matera Laser Ranging Observatory (MLRO): An overview

    NASA Technical Reports Server (NTRS)

    Varghese, Thomas K.; Decker, Winfield M.; Crooks, Henry A.; Bianco, Giuseppe

    1993-01-01

    The Agenzia Spaziale Italiana (ASI) is currently under negotiation with the Bendix Field Engineering Corporation (BFEC) of the Allied Signal Aerospace Company (ASAC) to build a state-of-the-art laser ranging observatory for the Centro di Geodesia Spaziale, in Matera, Italy. The contract calls for the delivery of a system based on a 1.5 meter afocal Cassegrain astronomical quality telescope with multiple ports to support a variety of experiments for the future, with primary emphasis on laser ranging. Three focal planes, viz. Cassegrain, Coude, and Nasmyth will be available for these experiments. The open telescope system will be protected from dust and turbulence using a specialized dome which will be part of the building facilities to be provided by ASI. The fixed observatory facility will be partitioned into four areas for locating the following: laser, transmit/receive optics, telescope/dome enclosure, and the operations console. The optical tables and mount rest on a common concrete pad for added mechanical stability. Provisions will be in place for minimizing the effects of EMI, for obtaining maximum cleanliness for high power laser and transmit optics, and for providing an ergonomic environment fitting to a state-of-the-art multipurpose laboratory. The system is currently designed to be highly modular and adaptable for scaling or changes in technology. It is conceived to be a highly automated system with superior performance specifications to any currently operational system. Provisions are also made to adapt and accommodate changes that are of significance during the course of design and integration.

  2. Social network site addiction - an overview.

    PubMed

    Andreassen, Cecilie Schou; Pallesen, Ståle

    2014-01-01

    Research into frequent, excessive, and compulsive social network activity has increased the last years, in which terms such as "social network site addiction" and "Facebook addiction" have been used interchangeably. The aim of this review is to offer more knowledge and better understanding of social network site addiction (SNS-addiction) among researchers as well as clinicians by presenting a narrative overview of the research field in terms of definition, measurement, antecedents, consequences, and treatment as well as recommendations for future research efforts. Seven different measures of SNS-addiction have been developed, although they have to a very little extent been validated against each other. The small number of studies conducted so far on this topic suggests that SNS-addiction is associated with health-related, academic, and interpersonal problems/issues. However such studies have relied on a simple cross-sectional study design. It is therefore hard to draw any conclusions about potential causality and long-term effects at this point, beyond hypothetical speculations. Empirical studies suggest that SNS-addiction is caused by dispositional factors (e.g., personality, needs, self-esteem), although relevant explanatory socio-cultural and behavioral reinforcement factors remain to be empirically explored. No well-documented treatment for SNS-addiction exists, but knowledge gained from Internet addiction treatment approaches might be transferable to SNS-addiction. Overall, the research on this topic is in its infancy, and as such the SNS-addiction construct needs further conceptual and empirical exploration. There is a great demand for studies using careful longitudinal designs and studies which include objective measures of both behavior and health based on broad representative samples. PMID:24001298

  3. Migration in south Asia: an overview.

    PubMed

    Skeldon, R

    1983-01-01

    Past studies on migration patterns and flows in south Asia have been based on limited data. The present overview is based on a detailed study of census and survey data reaching back to the early 1950's. The study incorporates the thinking of several research scholars who have dealt with specialized areas of migration in individual countries, and in the region as a whole. The interrelationships between migration and development are considered in a final chapter, with special mention of future trends, associated with traditional practices and historical circumstances. Migration will be of great importance in the coming decades. The activities of "sons of soil" anti-migrant movements and anti-migrant legislation have had little, if any, effect on migration flows. As the population increases in villages and towns and jobs become scarce, migration is likely to become even more of a political issue. Less politically volatile is circulation between village and town or between villages, whereby the migrants can have access to resources in 2 or more places. This option may play a critical role in the continued survival of much of the population in the future. This has been perhaps the most important factor in explaining the relatively slow rate of urbanization in south Asia as it allowed the rural people to take advantage of the towns without causing a massive and permanent transfer of population. The numbers who practice this "bilocality" are therefore likely to increase and migrants will continue to make up more significant proportions of the urban populations than their contribution to urban growth would suggest owing to the importance of "turnover migration." However, this circulation is not a new phenomenon: India and the other countries of south Asia have been characterized by tremendous mobility of population through circulation for considerable time but both its volume, and the distances over which it occurs are likely to increase as these countries develop. PMID

  4. An overview of polylactides as packaging materials.

    PubMed

    Auras, Rafael; Harte, Bruce; Selke, Susan

    2004-09-16

    Polylactide polymers have gained enormous attention as a replacement for conventional synthetic packaging materials in the last decade. By being truly biodegradable, derived from renewable resources and by providing consumers with extra end-use benefits such as avoiding paying the "green tax" in Germany or meeting environmental regulations in Japan, polylactides (PLAs) are a growing alternative as a packaging material for demanding markets. The aim of this paper is to review the production techniques for PLAs, summarize the main properties of PLA and to delineate the main advantages and disadvantages of PLA as a polymeric packaging material. PLA films have better ultraviolet light barrier properties than low density polyethylene (LDPE), but they are slightly worse than those of cellophane, polystyrene (PS) and poly(ethylene terephthalate) (PET). PLA films have mechanical properties comparable to those of PET and better than those of PS. PLA also has lower melting and glass transition temperatures than PET and PS. The glass transition temperature of PLA changes with time. Humidity between 10 and 95% and storage temperatures of 5 to 40 degrees C do not have an effect on the transition temperature of PLA, which can be explained by its low water sorption values (i.e. <100 ppm at Aw = 1). PLA seals well at temperatures below the melting temperature but an appreciable shrinking of the films has been noted when the material is sealed near its melting temperature. Solubility parameter predictions indicate that PLA will interact with nitrogen compounds, anhydrides and some alcohols and that it will not interact with aromatic hydrocarbons, ketones, esters, sulfur compounds or water. The CO2, O2 and water permeability coefficients of PLA are lower than those of PS and higher than those of PET. Its barrier to ethyl acetate and D-limonene is comparable to PET. The amount of lactic acid and its derivatives that migrate to food simulant solutions from PLA is much lower than any

  5. Fluid mechanics of eating, swallowing and digestion - overview and perspectives.

    PubMed

    Engmann, Jan; Burbidge, Adam S

    2013-02-26

    From a very simplistic viewpoint, the human digestive system can be regarded as a long tube (with dramatic variations in diameter, cross-section, wall properties, pumping mechanisms, regulating valves and in-line sensors). We single out a few fluid mechanical phenomena along the trajectory of a food bolus from the mouth to the small intestine and discuss how they influence sensorial perception, safe transport, and nutrient absorption from a bolus. The focus is on lubrication flows between the tongue and palate, the oropharyngeal stage of swallowing and effects of flow on absorption in the small intestine. Specific challenges and opportunities in this research area are highlighted. PMID:23233019

  6. Remote conditioning the heart overview: translatability and mechanism

    PubMed Central

    Schmidt, Michael Rahbek; Redington, Andrew; Bøtker, Hans Erik

    2015-01-01

    Conditioning the heart to resist predictable and unpredictable ischaemia–reperfusion (IR) injury is one of the fastest growing areas of bench to bedside research within cardiology. Basic science has provided important insights into signalling pathways and protective mechanisms in the heart, and a growing number of clinical studies have, with important exceptions, shown the potential applicability and beneficial effect of various mechanical conditioning strategies achieved by intermittent short-lasting-induced ischaemia of the heart itself or a remote tissue. Remote ischaemic conditioning (RIC) in particular has been utilized in a number of clinical settings with promising results. However, while many novel ‘downstream’ mechanisms of RIC have been discovered, translation to pharmacological conditioning has not yet been convincingly demonstrated in clinical studies. One explanation for this apparent failure may be that most pharmacological approaches mimic a single instrument in a complex orchestra activated by mechanical conditioning. Recent studies, however, provide important insights into upstream events occurring in RIC, which may allow for development of drugs activating more complex systems of biological organ protection. With this review, we will systematically examine the first generation of pharmacological cardioprotection studies and then provide a summary of the recent discoveries in basic science that could illuminate the path towards more advanced approaches in the next generation of pharmacological agents that may work by reproducing the diverse effects of RIC, thereby providing protection against IR injury. PMID:25219984

  7. Validation and Comprehension: An Integrated Overview

    ERIC Educational Resources Information Center

    Kendeou, Panayiota

    2014-01-01

    In this article, I review and discuss the work presented in this special issue while focusing on a number of issues that warrant further investigation in validation research. These issues pertain to the nature of the validation processes, the processes and mechanisms that support validation during comprehension, the factors that influence…

  8. Occupancy Chargeback: An Overview of Different Models and a Glimpse of 'One' Future.

    ERIC Educational Resources Information Center

    Bradley, Garry; Mozjerin, Con

    2001-01-01

    Presents an overview of factors motivating the occupancy chargeback movement on today's campuses. Examines the two basic models with particular reference to RMIT University (Australia), and discusses what associated support mechanisms may be required. Concluding comments address activity-based costing. (GR)

  9. An overview of American higher education.

    PubMed

    Baum, Sandy; Kurose, Charles; McPherson, Michael

    2013-01-01

    This overview of postsecondary education in the United States reviews the dramatic changes over the past fifty years in the students who go to college, the institutions that produce higher education, and the ways it is financed. The article, by Sandy Baum, Charles Kurose, and Michael McPherson, creates the context for the articles that follow on timely issues facing the higher education community and policy makers. The authors begin by observing that even the meaning of college has changed. The term that once referred primarily to a four-year period of academic study now applies to virtually any postsecondary study--academic or occupational, public or private, two-year or four-year-- that can result in a certificate or degree. They survey the factors underlying the expansion of postsecondary school enrollments; the substantial increases in female, minority, disadvantaged, and older students; the development of public community colleges; and the rise of for-profit colleges. They discuss the changing ways in which federal and state governments help students and schools defray the costs of higher education as well as more recent budget tensions that are now reducing state support to public colleges. And they review the forces that have contributed to the costs of producing higher education and thus rising tuitions. The authors also cite evidence on broad measures of college persistence and outcomes, including low completion rates at community and for-profit colleges, the increasing need for remedial education for poorly prepared high school students, and a growing gap between the earnings of those with a bachelor's degree and those with less education. They disagree with critics who say that investments in higher education, particularly for students at the margin, no longer pay off. A sustained investment in effective education at all levels is vital to the nation's future, they argue. But they caution that the American public no longer seems willing to pay more for

  10. Expert Systems: An Overview for Teacher-Librarians.

    ERIC Educational Resources Information Center

    Orwig, Gary; Barron, Ann

    1992-01-01

    Provides an overview of expert systems for teacher librarians. Highlights include artificial intelligence and expert systems; the development of the MYCIN medical expert system; rule-based expert systems; the use of expert system shells to develop a specific system; and how to select an appropriate application for an expert system. (11 references)…

  11. Fractures of distal radius: an overview.

    PubMed

    Meena, Sanjay; Sharma, Pankaj; Sambharia, Abhishek Kumar; Dawar, Ashok

    2014-01-01

    Fractures of distal radius account for up to 20% of all fractures treated in emergency department. Initial assessment includes a history of mechanism of injury, associated injury and appropriate radiological evaluation. Treatment options include conservative management, internal fixation with pins, bridging and non-bridging external fixation, dorsal or volar plating with/without arthroscopy assistance. However, many questions regarding these fractures remain unanswered and good prospective randomized trials are needed. PMID:25657938

  12. Fractures of Distal Radius: An Overview

    PubMed Central

    Meena, Sanjay; Sharma, Pankaj; Sambharia, Abhishek Kumar; Dawar, Ashok

    2014-01-01

    Fractures of distal radius account for up to 20% of all fractures treated in emergency department. Initial assessment includes a history of mechanism of injury, associated injury and appropriate radiological evaluation. Treatment options include conservative management, internal fixation with pins, bridging and non-bridging external fixation, dorsal or volar plating with/without arthroscopy assistance. However, many questions regarding these fractures remain unanswered and good prospective randomized trials are needed. PMID:25657938

  13. An overview on plant cuticle biomechanics.

    PubMed

    Domínguez, Eva; Cuartero, Jesús; Heredia, Antonio

    2011-08-01

    Plant biomechanics combines the principles of physics, chemistry and engineering to answer questions about plant growth, development and interaction with the environment. The epidermal-growth-control theory, postulated in 1867 and verified in 2007, states that epidermal cells determine the rate of organ elongation since they are under tension, while inner tissues are under compression. The lipid cuticle layer is deposited on the surface of outer epidermal cell walls and modifies the chemical and mechanical nature of these cell walls. Thus, the plant cuticle plays a key role in plant interaction with the environment and in controlling organ expansion. Rheological analyses indicate that the cuticle is a mostly viscoelastic and strain-hardening material that stiffens the comparatively more elastic epidermal cell walls. Cuticle stiffness can be attributed to polysaccharides and flavonoids present in the cuticle whereas a cutin matrix is mainly responsible for its extensibility. Environmental conditions such as temperature and relative humidity have a plasticizing effect on the mechanical properties of cuticle since they lower cuticle stiffness and strength. The external appearance of agricultural commodities, especially fruits, is of great economic value. Mechanical properties of the cuticle can have a positive or negative effect on disorders like fruit cracking, fungal pathogen penetration and pest infestation. Cuticle rheology has significant variability within a species and thus can be subjected to selection in order to breed cultivars resistant to pests, infestation and disorders. PMID:21683870

  14. Cannabidiol: an overview of some pharmacological aspects.

    PubMed

    Mechoulam, Raphael; Parker, Linda A; Gallily, Ruth

    2002-11-01

    Over the past few years, considerable attention has focused on cannabidiol (CBD), a major nonpsychotropic constituent of cannabis. The authors present a review on the chemistry of CBD and discuss the anticonvulsive, antianxiety, antipsychotic, antinausea, and antirheumatoid arthritic properties of CBD. CBD does not bind to the known cannabinoid receptors, and its mechanism of action is yet unknown. It is possible that, in part at least, its effects are due to its recently discovered inhibition of anandamide uptake and hydrolysis and to its antioxidative effect. PMID:12412831

  15. An overview of the SAFSIM computer program

    SciTech Connect

    Dobranich, D.

    1993-01-01

    SAFSIM (System Analysis Flow SIMulator) is a FORTRAN computer program that provides engineering simulations of user-specified flow networks at the system level. It includes fluid mechanics, heat transfer, and reactor dynamics capabilities. SAFSIM provides sufficient versatility to allow the simulation of almost any flow system, from a backyard sprinkler system to a clustered nuclear reactor propulsion system. In addition to versatility, speed and robustness are primary goals of SAFSIM development. The current capabilities of SAFSIM are summarized and some sample applications are presented. It is applied here to a nuclear thermal propulsion system and nuclear rocket engine test facility.

  16. Recurrent oral ulcers--an overview.

    PubMed

    Gaffar, A

    2001-01-01

    Recurrent oral ulcers (ROUs) are the most common oral mucosal disease. The etiology of ROUs is complex. The factors include mechanical trauma, genetics, stress, smoking, and viral and bacterial infections. Treatment modalities depend on the differential diagnosis of ROUs and could consist of antimicrobial agents, anti-inflammatory agents, immunomodulators, or over-the-counter medications. New therapy available in the form of a coating polymer, Colgate ORABASE Soothe.N.Seal, is clinically proven to provide rapid relief and healing of ROUs. PMID:11915640

  17. Basic mechanisms of catastrophic epilepsy – overview from animal models

    PubMed Central

    Galanopoulou, Aristea S.

    2013-01-01

    Infantile spasms are age-specific seizures of infantile epileptic encephalopathies that are usually associated with poor epilepsy and neurodevelopmental outcomes. The current treatments are not always effective and may be associated with significant side effects. Various mechanisms have been proposed as pathogenic for infantile spasms, including cortical or brainstem dysfunction, disruption of normal cortical-subcortical communications, genetic defects, inflammation, stress, developmental abnormalities. Many of these have been recently tested experimentally, resulting into the emergence of several animal models of infantile spasms. The stress theory of spasms yielded the corticotropin releasing hormone (CRH) induced model, which showed the higher proconvulsant potency of CRH in developing rats, although only limbic seizures were observed. Models of acute induction of infantile spasms in rodents include the N-methyl-D-aspartate (NMDA) model of emprosthotonic seizures, the prenatal betamethasone and prenatal stress variants of the NMDA model, and the γ-butyrolactone induced spasms in a Down’s syndrome mouse model. Chronic rodent models of infantile spasms include the tetrodotoxin model and the multiple-hit models in rats, as well as two genetic mouse models of interneuronopathies with infantile spasms due to loss of function of the aristaless X-linked homeobox related gene (ARX). This review discusses the emerging mechanisms for generation of infantile spasms and their associated chronic epileptic and dyscognitive phenotype as well as the recent progress in identifying pathways to better treat this epileptic encephalopathy. PMID:23312951

  18. Neural correlates of math anxiety – an overview and implications

    PubMed Central

    Artemenko, Christina; Daroczy, Gabriella; Nuerk, Hans-Christoph

    2015-01-01

    Math anxiety is a common phenomenon which can have a negative impact on numerical and arithmetic performance. However, so far little is known about the underlying neurocognitive mechanisms. This mini review provides an overview of studies investigating the neural correlates of math anxiety which provide several hints regarding its influence on math performance: while behavioral studies mostly observe an influence of math anxiety on difficult math tasks, neurophysiological studies show that processing efficiency is already affected in basic number processing. Overall, the neurocognitive literature suggests that (i) math anxiety elicits emotion- and pain-related activation during and before math activities, (ii) that the negative emotional response to math anxiety impairs processing efficiency, and (iii) that math deficits triggered by math anxiety may be compensated for by modulating the cognitive control or emotional regulation network. However, activation differs strongly between studies, depending on tasks, paradigms, and samples. We conclude that neural correlates can help to understand and explore the processes underlying math anxiety, but the data are not very consistent yet. PMID:26388824

  19. Digital Libraries and Digitisation: An Overview and Critique

    ERIC Educational Resources Information Center

    Rikowski, Ruth

    2008-01-01

    This article provides an overview of some of the main areas surrounding the broad topic of "Digital Libraries". This includes the advantages and costs of digitisation; the traditional and digital library; the library community and digitisation; and an examination of various digital library projects. It is not exhaustive, but hopefully, it provides…

  20. An Overview of Training in the Public Sector.

    ERIC Educational Resources Information Center

    Smith, David A.

    This report provides an overview of the training and education received by public sector employees, estimates of public funds expended for this training, recent trends, and identification of policy issues for future study. Chapter 1, an introduction, summarizes the content of chapters 2 and 3. Chapter 2 describes the major portions of the public…

  1. Mechanical Overview of the International X-Ray Observatory

    NASA Technical Reports Server (NTRS)

    Robinson, David W.; McClelland, Ryan S.

    2009-01-01

    The International X-ray Observatory (IXO) is a new collaboration between NASA, ESA, and JAXA which is under study for launch in 2020. IXO will be a large 6600 kilogram Great Observatory-class mission which will build upon the legacies of the Chandra and XMM-Newton X-ray observatories. It combines elements from NASA's Constellation-X program and ESA's XEUS program. The observatory will have a 20-25 meter focal length, which necessitates the use of a deployable instrument module. Currently the project is actively trading configurations and layouts of the various instruments and spacecraft components. This paper will provide a snapshot of the latest observatory configuration under consideration and summarize the observatory from the mechanical engineering perspective.

  2. Data integration in biological research: an overview.

    PubMed

    Lapatas, Vasileios; Stefanidakis, Michalis; Jimenez, Rafael C; Via, Allegra; Schneider, Maria Victoria

    2015-12-01

    Data sharing, integration and annotation are essential to ensure the reproducibility of the analysis and interpretation of the experimental findings. Often these activities are perceived as a role that bioinformaticians and computer scientists have to take with no or little input from the experimental biologist. On the contrary, biological researchers, being the producers and often the end users of such data, have a big role in enabling biological data integration. The quality and usefulness of data integration depend on the existence and adoption of standards, shared formats, and mechanisms that are suitable for biological researchers to submit and annotate the data, so it can be easily searchable, conveniently linked and consequently used for further biological analysis and discovery. Here, we provide background on what is data integration from a computational science point of view, how it has been applied to biological research, which key aspects contributed to its success and future directions. PMID:26336651

  3. Innate immunity in vertebrates: an overview.

    PubMed

    Riera Romo, Mario; Pérez-Martínez, Dayana; Castillo Ferrer, Camila

    2016-06-01

    Innate immunity is a semi-specific and widely distributed form of immunity, which represents the first line of defence against pathogens. This type of immunity is critical to maintain homeostasis and prevent microbe invasion, eliminating a great variety of pathogens and contributing with the activation of the adaptive immune response. The components of innate immunity include physical and chemical barriers, humoral and cell-mediated components, which are present in all jawed vertebrates. The understanding of innate defence mechanisms in non-mammalian vertebrates is the key to comprehend the general picture of vertebrate innate immunity and its evolutionary history. This is also essential for the identification of new molecules with applications in immunopharmacology and immunotherapy. In this review, we describe and discuss the main elements of vertebrate innate immunity, presenting core findings in this field and identifying areas that need further investigation. PMID:26878338

  4. Radar response of vegetation: An overview

    NASA Technical Reports Server (NTRS)

    Ulaby, Fawwaz T.; Dobson, M. Craig

    1993-01-01

    This document contains a number of viewgraphs on surface and vegetation backscattering. A classification of vegetation based on general scattering properties is presented. Radar scattering mechanisms are discussed, and backscattering and reflection coefficients for soil back scattering models are given. Radar response to vegetation is presented, with the objectives to discriminate and classify vegetation; to estimate biomass, leaf area index (LAI), and soil moisture; and to monitor changes, including deforestation and growth. Both theory and observation (laboratory, field, air SAR, and European Remote Sensing Satellite (ERS-1) observations) are used to present backscatter coefficients and other data for various vegetation types. ERS-1 results include class statistics, comparison with theory, and biomass response and seasonal variation (LAI) for deciduous and coniferous forests.

  5. Open peer review at four STEM journals: an observational overview

    PubMed Central

    Ford, Emily

    2015-01-01

    Open peer review, peer review where authors' and reviewers' identities are disclosed to one another, is a growing trend in scholarly publishing. Through observation of four journals in STEM disciplines, PLOS One, Atmospheric Chemistry & Physics, PeerJ, and F1000Research, an observational overview is conducted. The overview relies on defined characteristics of open peer review. Results show that despite differing open peer review implementations, each journal retains editorial involvement in scholarly publishing. Further, the analysis shows that only one of these implementations is fully transparent in its peer review and decision making process. Finally, the overview contends that journals should clearly outline peer review and editorial processes in order to allow for open peer review to be better understood and adopted by authors, reviewers, editors, and readers of science communications. PMID:25767695

  6. Red blood cell-derived microparticles: An overview.

    PubMed

    Westerman, Maxwell; Porter, John B

    2016-07-01

    The red blood cell (RBC) is historically the original parent cell of microparticles (MPs). In this overview, we describe the discovery and the early history of red cell-derived microparticles (RMPs) and present an overview of the evolution of RMP. We report the formation, characteristics, effects of RMP and factors which may affect RMP evaluation. The review examines RMP derived from both normal and pathologic RBC. The pathologic RBC studies include sickle cell anemia (SCA), sickle cell trait (STr), thalassemia intermedia (TI), hereditary spherocytosis (HS), hereditary elliptocytosis (HE), hereditary stomatocytosis (HSt) and glucose-6-phosphate dehydrogenase deficiency (G6PD). PMID:27282583

  7. An overview of flux braiding experiments

    PubMed Central

    Wilmot-Smith, A. L.

    2015-01-01

    In a number of papers dating back to the 1970s, Parker has hypothesized that, in a perfectly ideal environment, complex photospheric motions acting on a continuous magnetic field will result in the formation of tangential discontinuities corresponding to singular currents. I review direct numerical simulations of the problem and find that the evidence points to a tendency for thin but finite-thickness current layers to form, with thickness exponentially decreasing in time. Given a finite resistivity, these layers will eventually become important and cause the dynamical process of energy release. Accordingly, a body of work focuses on evolution under continual boundary driving. The coronal volume evolves into a highly dynamic but statistically steady state where quantities have a temporally and spatially intermittent nature and where the Poynting flux and dissipation are decoupled on short time scales. Although magnetic braiding is found to be a promising coronal heating mechanism, much work remains to determine its true viability. Some suggestions for future study are offered. PMID:25897088

  8. Korean Studies on Blood Stasis: An Overview

    PubMed Central

    Jung, Jeeyoun; Lee, Ju Ah; Yun, Kyung-Jin

    2015-01-01

    Blood stasis is one of the important pathological concepts in Korean medicine. We analyzed the Korean studies concerning blood stasis. We searched for articles in eight electronic databases from their inception to September, 2014. We included reviews, clinical studies, and preclinical studies that had studied blood stasis and excluded articles in which blood stasis was not mentioned or in which the original authors had not explained blood stasis. Of 211 total included studies, 19 were reviews, 52 were clinical studies, and 140 were preclinical articles. “Stagnant blood within the body” was the most frequently mentioned phrase of the traditional concept of blood stasis. Traumatic injury was the most frequently studied disease/condition in the clinical studies. In the preclinical studies, coagulopathy was studied most frequently, followed by hyperviscosity, hyperlipidemia, inflammation, neoplasm, ischemic brain injury, and atherosclerosis. Hyeolbuchukeo-tang and Angelicae Gigantis Radix were the most frequent formula and single herb, respectively, used in the blood stasis researches. The results showed that blood stasis was mainly recognized as disorder of circulation and many studies showed the effectiveness of activating blood circulating herbs for diseases and pathologies such as traumatic injury or coagulopathy. Further studies are needed in the pathologic mechanisms and various diseases of blood stasis. PMID:25821483

  9. Krill Products: An Overview of Animal Studies

    PubMed Central

    Burri, Lena; Johnsen, Line

    2015-01-01

    Many animal studies have been performed with krill oil (KO) and this review aims to summarize their findings and give insight into the mechanism of action of KO. Animal models that have been used in studies with KO include obesity, depression, myocardial infarction, chronic low-grade and ulcerative inflammation and are described in detail. Moreover, studies with KO in the form of krill powder (KP) and krill protein concentrate (KPC) as a mix of lipids and proteins are mentioned and compared to the effects of KO. In addition, differences in tissue uptake of the long-chain omega-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), when delivered in either phospholipid or triglyceride form, are addressed and the differential impact the delivery form has on gene expression profiles is explained. In our outlook, we try to highlight the potential of KO and KP supplementation in clinical settings and discuss health segments that have a high potential of showing krill product specific health benefits and warrant further clinical investigations. PMID:25961320

  10. Krill products: an overview of animal studies.

    PubMed

    Burri, Lena; Johnsen, Line

    2015-05-01

    Many animal studies have been performed with krill oil (KO) and this review aims to summarize their findings and give insight into the mechanism of action of KO. Animal models that have been used in studies with KO include obesity, depression, myocardial infarction, chronic low-grade and ulcerative inflammation and are described in detail. Moreover, studies with KO in the form of krill powder (KP) and krill protein concentrate (KPC) as a mix of lipids and proteins are mentioned and compared to the effects of KO. In addition, differences in tissue uptake of the long-chain omega-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), when delivered in either phospholipid or triglyceride form, are addressed and the differential impact the delivery form has on gene expression profiles is explained. In our outlook, we try to highlight the potential of KO and KP supplementation in clinical settings and discuss health segments that have a high potential of showing krill product specific health benefits and warrant further clinical investigations. PMID:25961320

  11. [An overview of prophylactic therapy for migraine].

    PubMed

    Shimizu, Toshihiko

    2009-10-01

    The launch of triptans has significantly changed the treatment of migraine, leading to great improvement in the quality of life (QOL) of migraine patients. In routine clinical settings, few patients present with migraine attacks that clearly deviate from the typical frequency and severity of migraine, and migraine that is difficult to control with acute-phase treatment alone is frequently encountered. Under these circumstances, the importance of prophylactic therapy, including lifestyle guidance and drug treatment, has attracted attention. However, in Japan, only a small number of prophylactics are currently indicated for migraine, and the available options are insufficient. In this study, I have outlined the prophylactic strategies for migraine, including lifestyle guidance, on the basis of literature published in Europe and North America. In addition, I have presented my clinical experiences and research reports to introduce cases of migraine for which prophylactic therapy was indicated, to hypothesize the mechanisms of the prophylatic activity of specific drugs (e.g., anti-convulsants, anti-depressants, beta-blockers, AII antagonists, Ca channel blockers, leukotriene receptor antagonists, statins, anti-herpes zoster virus drugs) for their prophylactic effect on migraine, and to determine drug regimens. PMID:19882936

  12. Hypertension and acute myocardial infarction: an overview.

    PubMed

    Pedrinelli, Roberto; Ballo, Piercarlo; Fiorentini, Cesare; Denti, Silvia; Galderisi, Maurizio; Ganau, Antonello; Germanò, Giuseppe; Innelli, Pasquale; Paini, Anna; Perlini, Stefano; Salvetti, Massimo; Zacà, Valerio

    2012-03-01

    History of hypertension is a frequent finding in patients with acute myocardial infarction (AMI) and its recurring association with female sex, diabetes, older age, less frequent smoking and more frequent vascular comorbidities composes a risk profile quite distinctive from the normotensive ischemic counterpart.Antecedent hypertension associates with higher rates of death and morbid events both during the early and long-term course of AMI, particularly if complicated by left ventricular dysfunction and/or congestive heart failure. Renin-angiotensin-aldosterone system blockade, through either angiotensin-converting enzyme inhibition, angiotensin II receptor blockade or aldosterone antagonism, exerts particular benefits in that high-risk hypertensive subgroup.In contrast to the negative implications carried by antecedent hypertension, higher systolic pressure at the onset of chest pain associates with lower mortality within 1 year from coronary occlusion, whereas increased blood pressure recorded after hemodynamic stabilization from the acute ischemic event bears inconsistent relationships with recurring coronary events in the long-term follow-up.Whether antihypertensive treatment in post-AMI hypertensive patients prevents ischemic relapses is uncertain. As a matter of fact, excessive diastolic pressure drops may jeopardize coronary perfusion and predispose to new acute coronary events, although the precise cause-effect mechanisms underlying this phenomenon need further evaluation. PMID:22317927

  13. Novel therapies for pemphigus vulgaris: an overview.

    PubMed

    Perez, Oliver A; Patton, Timothy

    2009-01-01

    Pemphigus comprises a group of autoimmune, mucocutaneous blistering disorders. Its principal cause may be a group of antibodies directed against proteins present on the surface of keratinocytes that provide mechanical structure to the epidermis. In the case of pemphigus vulgaris, the characteristic blistering noted just above the basal layer may be triggered by autoantibodies directed against desmoglein 3 (Dsg3). The process by which the binding of these antibodies leads to acantholysis, apoptosis and eventual loss of epidermal function is not completely understood. Current therapies are primarily directed against the formation of these antibodies by suppression of the immune system, and are associated with significant adverse events. As our understanding of the pathophysiology of pemphigus increases, newer therapies have been proposed and evaluated. These novel therapies include intravenous immunoglobulin, plasmapheresis, immunoadsorption, extracorporeal photochemotherapy, biological agents, as well as experimental therapies such as cholinergic receptor agonists, Dsg3 peptides and a p38 mitogen-activated protein kinase inhibitor. Current limitations to the widespread use of these therapies include cost, a lack of consistent data regarding their benefit, limited availability, and the experimental nature of some of the treatments. This review highlights the latest case reports and studies that employ established as well as new therapeutics in a novel way to treat this rare, but serious, disorder. PMID:19761276

  14. Minimally invasive knee arthroplasty: An overview

    PubMed Central

    Tria, Alfred J; Scuderi, Giles R

    2015-01-01

    Minimally invasive surgery (MIS) for arthroplasty of the knee began with surgery for unicondylar knee arthroplasty (UKA). Partial knee replacements were designed in the 1970s and were amenable to a more limited exposure. In the 1990s Repicci popularized the MIS for UKA. Surgeons began to apply his concepts to total knee arthroplasty. Four MIS surgical techniques were developed: quadriceps sparing, mini-mid vastus, mini-subvastus, and mini-medial parapatellar. The quadriceps sparing technique is the most limited one and is also the most difficult. However, it is the least invasive and allows rapid recovery. The mini-midvastus is the most common technique because it affords slightly better exposure and can be extended. The mini-subvastus technique entirely avoids incising the quadriceps extensor mechanism but is time consuming and difficult in the obese and in the muscular male patient. The mini-parapatellar technique is most familiar to surgeons and represents a good starting point for surgeons who are learning the techniques. The surgeries are easier with smaller instruments but can be performed with standard ones. The techniques are accurate and do lead to a more rapid recovery, with less pain, less blood loss, and greater motion if they are appropriately performed. PMID:26601062

  15. Solar Ready: An Overview of Implementation Practices

    SciTech Connect

    Watson, A.; Guidice, L.; Lisell, L.; Doris, L.; Busche, S.

    2012-01-01

    This report explores three mechanisms for encouraging solar ready building design and construction: solar ready legislation, certification programs for solar ready design and construction, and stakeholder education. These methods are not mutually exclusive, and all, if implemented well, could contribute to more solar ready construction. Solar ready itself does not reduce energy use or create clean energy. Nevertheless, solar ready building practices are needed to reach the full potential of solar deployment. Without forethought on incorporating solar into design, buildings may be incompatible with solar due to roof structure or excessive shading. In these cases, retrofitting the roof or removing shading elements is cost prohibitive. Furthermore, higher up-front costs due to structural adaptations and production losses caused by less than optimal roof orientation, roof equipment, or shading will lengthen payback periods, making solar more expensive. With millions of new buildings constructed each year in the United States, solar ready can remove installation barriers and increase the potential for widespread solar adoption. There are many approaches to promoting solar ready, including solar ready legislation, certification programs, and education of stakeholders. Federal, state, and local governments have the potential to implement programs that encourage solar ready and in turn reduce barriers to solar deployment. With the guidance in this document and the examples of jurisdictions and organizations already working to promote solar ready building practices, federal, state, and local governments can guide the market toward solar ready implementation.

  16. Microbial Degradation of Petroleum Hydrocarbon Contaminants: An Overview

    PubMed Central

    Das, Nilanjana; Chandran, Preethy

    2011-01-01

    One of the major environmental problems today is hydrocarbon contamination resulting from the activities related to the petrochemical industry. Accidental releases of petroleum products are of particular concern in the environment. Hydrocarbon components have been known to belong to the family of carcinogens and neurotoxic organic pollutants. Currently accepted disposal methods of incineration or burial insecure landfills can become prohibitively expensive when amounts of contaminants are large. Mechanical and chemical methods generally used to remove hydrocarbons from contaminated sites have limited effectiveness and can be expensive. Bioremediation is the promising technology for the treatment of these contaminated sites since it is cost-effective and will lead to complete mineralization. Bioremediation functions basically on biodegradation, which may refer to complete mineralization of organic contaminants into carbon dioxide, water, inorganic compounds, and cell protein or transformation of complex organic contaminants to other simpler organic compounds by biological agents like microorganisms. Many indigenous microorganisms in water and soil are capable of degrading hydrocarbon contaminants. This paper presents an updated overview of petroleum hydrocarbon degradation by microorganisms under different ecosystems. PMID:21350672

  17. Multi-wavelength analysis of young pulsars: an overview.

    NASA Astrophysics Data System (ADS)

    Maritz, J. M.; Meintjes, P. J.; Buchner, S. J.

    Young pulsars emit a broad spectrum of radiation that range from radio to gamma ray energies. These pulsars are considered as rotation powered pulsars that spin rapidly and are strongly magnetized. Following the discovery of pulsars nearly four decades ago, the population of known pulsars already reached a number of roughly two thousand. This known population of pulsars includes both millisecond and normal pulsars that were discovered by several telescopes. We analyze both HartRAO radio data and Fermi gamma ray data of the Vela pulsar. We also explore a proposed method of probing the electron column density of the instellar gas through analyzing the gamma ray diffuse data associated with the Fermi two-year observation. This paper serves as an overview of gamma ray and radio timing analysis of bright young pulsars with respect to the use of open source timing analysis tools (Tempo2, Psrchive, Enrico and the Fermi tools). We reason that the multi-wavelength picture of pulsars can help clarify questions regarding the origin of pulsed radiation emission mechanisms in several energy bands, but that radio observations will prove adequate for timing noise analysis, given the accurate and long radio data sets. The process of identifying gravitational waves in timing data, rests on gaining a deeper insight into the timing noise phenomena.

  18. Talc as a Substitute for Dry Lubricant (an Overview)

    NASA Astrophysics Data System (ADS)

    Abdulkareem, Suleiman; Orkuma, Gideon I.; Apasi, Adaokoma A.

    2011-01-01

    All metal surfaces, irrespective of their surface integrity, appear as a series of peaks and valleys under close examination. The objective of lubrication is to separate these peaks and valleys so that contact is avoided in metal to metal, hence greatly reduce or eliminate wear. A lubricant may be gas, liquid, semi-solid, or solid that permits free action of mechanical devices and prevents damage by abrasion and seizing of metal or other components through unequal expansion caused by heat. Among the solid (dry) lubricants includes: graphite, glass, boron nitride, polytetrafluoroethene (PTFE-Teflon), molybdenum disulfide, tungsten disulfide, lime, talc, etc. Solid (dry) lubricants differ significantly from liquid lubricants, in that liquid lubricants reduce friction due to their fluidity and viscosity. However, solid lubricants have neither of these properties but they are still capable of reducing friction and wear in metal. In this work, the study of the property characteristics of talc as a substitute for graphite in dry lubrication (an overview) was carried out and reported in this paper.

  19. Experimental Studies with Nematodes in Ecotoxicology: An Overview

    PubMed Central

    Hägerbäumer, Arne; Höss, Sebastian; Heininger, Peter; Traunspurger, Walter

    2015-01-01

    With respect to their high abundances, their role as intermediaries between microorganisms and higher trophic levels, and their ubiquitous occurrence in all habitats, nematodes are of strong potential interest as environmental indicators. Ecotoxicological methods to evaluate the risk of anthropogenic pollutants on ecosystems require both in vitro and in vivo toxicity tests to investigate either mechanisms or pathways of toxicity and to set accurate toxicity thresholds. For this, the interest in nematodes as model organisms in ecotoxicology increased over the past few decades and existing appropriate experimental methods are reviewed in this manuscript. An overview of the various existing ecotoxicological tools for nematodes, ranging from molecular laboratory methods to experimental model ecosystem approaches, and their role as indicator organisms is given. The reviewed studies, approaches that range from species-based to community-based methods, reveal exciting possibilities for the future use of nematodes in ecotoxicological studies. Suitable ecotoxicological tools and ecological indices for nematodes should be integrated in weight-of-evidence approaches for assessing the ecological risk of contamination. PMID:25861113

  20. Autoimmune Diabetes: An Overview of Experimental Models and Novel Therapeutics.

    PubMed

    You, Sylvaine; Chatenoud, Lucienne

    2016-01-01

    Type 1 diabetes (T1D) results from a chronic and selective destruction of insulin-secreting β-cells within the islets of Langerhans of the pancreas by autoreactive CD4(+) and CD8(+) T lymphocytes. The use of animal models of T1D was instrumental for deciphering the steps of the autoimmune process leading to T1D. The non-obese diabetic (NOD) mouse and the bio-breeding (BB) rat spontaneously develop the disease similar to the human pathology in terms of the immune responses triggering autoimmune diabetes and of the genetic and environmental factors influencing disease susceptibility. The generation of genetically modified models allowed refining our understanding of the etiology and the pathogenesis of the disease. In the present review, we provide an overview of the experimental models generated and used to gain knowledge on the molecular and cellular mechanisms underlying the breakdown of self-tolerance in T1D and the progression of the autoimmune response. Immunotherapeutic interventions designed in these animal models and translated into the clinical arena in T1D patients will also be discussed. PMID:26530798

  1. Induction therapy in renal transplantation : an overview of current developments.

    PubMed

    Ciancio, Gaetano; Burke, George W; Miller, Joshua

    2007-01-01

    An overview of the past 10 years of clinical renal transplantation would include progress in the development of new induction protocols (non-depleting versus depleting monoclonal and polyclonal antibodies, plasmapheresis and intravenous immunoglobulins) designed to reduce the incidence and severity of rejection and adverse effects as well as improve long-term graft and patient survival. These modalities have been introduced primarily to reduce the incidence of acute rejection episodes leading to early graft loss, decrease the need for higher toxic doses of maintenance immunosuppressive drugs, such as calcineurin inhibitors, and possibly aid in the pursuit of the goal of achieving immunological tolerance and the avoidance of all long-term immunosuppressive therapy. What has resulted during the past 20 years as the use of induction agents has become more popular is the concurrent improvement in detection and treatment of acute and chronic infectious (primarily viral), and opportunistic and quasi-malignant disease accompanying the use of these agents and, therefore, their increase in popularity. However, the overall cost of therapy and the long-term results of protocols in which these agents have been used have not resulted in a definitive benefit thus far, because of the lack of sufficient numbers of defined randomised, long-term studies and the continuing introduction of newer protocols based on even more recent advances. The specific agents used for induction therapy to date, and the rationale for their introduction and mechanisms of action are discussed in this review. PMID:18062717

  2. Endoscopic haemostasis: an overview of procedures and clinical scenarios.

    PubMed

    Jacques, Jérémie; Legros, Romain; Chaussade, Stanislas; Sautereau, Denis

    2014-09-01

    Acute gastrointestinal bleeding is among the most urgent situations in daily gastroenterological practise. Endoscopy plays a key role in the diagnosis and treatment of such cases. Endoscopic haemostasis is probably the most important technical challenge that must be mastered by gastroenterologists. It is essential for both the management of acute gastrointestinal haemorrhage and the prevention of bleeding during high-risk endoscopic procedures. During the last decade, endoscopic haemostasis techniques and tools have grown in parallel with the number of devices available for endotherapy. Haemostatic powders, over-the-scope clips, haemostatic forceps, and other emerging technologies have changed daily practise and complement the standard available armamentarium (injectable, thermal, and mechanical therapy). Although there is a lack of strong evidence-based information on these procedures because of the difficulty in designing statistically powerful trials on this topic, physicians must be aware of all available devices to be able to choose the best haemostatic tool for the most effective procedure. We herein present an overview of procedures and clinical scenarios to optimise the management of gastrointestinal bleeding in daily practise. PMID:25022337

  3. HONO fluxes from soil surfaces: an overview

    NASA Astrophysics Data System (ADS)

    Wu, Dianming; Sörgel, Matthias; Tamm, Alexandra; Ruckteschler, Nina; Rodriguez-Caballero, Emilio; Cheng, Yafang; Pöschl, Ulrich; Weber, Bettina

    2016-04-01

    Gaseous nitrous acid (HONO) contributes up to 80% of atmospheric hydroxyl (OH) radicals and is also linked to health risks through reactions with tobacco smoke forming carcinogens. Field and modeling results suggested a large unknown HONO source in the troposphere during daytime. By measuring near ground HONO mixing ratio, up to 30% of HONO can be released from forest, rural and urban ground as well as snow surfaces. This source has been proposed to heterogeneous reactions of nitrogen dioxide (NO2) on humic acid surfaces or nitric acid photolysis. Laboratory studies showed that HONO emissions from bulk soil samples can reach 258 ng m‑2 s‑1 (in term of nitrogen), which corresponding to 1.1 × 1012 molecules cm‑2 s‑1and ˜ 100 times higher than most of the field studies, as measured by a dynamic chamber system. The potential mechanisms for soil HONO emissions include chemical equilibrium of acid-base reaction and gas-liquid partitioning between soil nitrite and HONO, but the positive correlation of HONO fluxes with pH (largest at neutral and slightly alkaline) points to the dominance of the formation process by ammonia-oxidizing bacteria (AOB). In general soil surface acidity, nitrite concentration and abundance of ammonia-oxidizing bacteria mainly regulate the HONO release from soil. A recent study showed that biological soil crusts in drylands can also emit large quantities of HONO and NO, corresponding to ˜20% of global nitrogen oxide emissions from soils under natural vegetation. Due to large concentrations of microorganisms in biological soil crusts, particularly high HONO and NO emissions were measured after wetting events. Considering large areas of arid and arable lands as well as peatlands, up to 70% of global soils are able to emitting HONO. However, the discrepancy between large soil HONO emissions measured in lab and low contributions of HONO flux from ground surfaces in field as well as the role of microorganisms should be further investigated.

  4. Rehabilitation interventions in multiple sclerosis: an overview.

    PubMed

    Beer, Serafin; Khan, Fary; Kesselring, Jürg

    2012-09-01

    Multiple sclerosis is a complex, heterogeneous disease associated with long-term disability. Despite the availability of advanced disease-modifying and symptomatic therapies that may decrease activity and progression of disease and alleviate complaints to a certain extent, there is still a need for comprehensive rehabilitation interventions in order to reduce sequels and symptoms of the disease on personal activities and social participation to achieve the highest possible independence and the best quality of life. Timing and setting of rehabilitation interventions should be selected individually depending on disease phase, functional deficits, personal requirements, as well as specific goals. In addition, limitations and disease-specific characteristics that may influence rehabilitation outcome should be noted. Rehabilitation interventions should be considered early for maintaining functional capacity and reducing risk for losing important abilities or independence. Due to gradual failure of adaptive compensatory mechanisms along the course of disease, benefits of rehabilitation interventions are generally higher in earlier phases of MS. Inpatient and outpatient multidisciplinary rehabilitation has been shown to be beneficial in improving disability, participation and quality of life despite progression of the disease. Good evidence exists for different specific interventions improving physical and cognitive performance. Other important issues responsible for beneficial effects of comprehensive rehabilitation in MS include education, instruction, and information of patients and caregivers. Comprehensive assessment of health domains in MS patients using standardized framework and common language for describing the impact of disease at different levels, using International Classification of Functioning, Disability and Health (ICF) core sets may increase the knowledge of needs of these patients for more efficient and adapted rehabilitation interventions meeting these

  5. The Pierre Auger Project: an overview

    NASA Astrophysics Data System (ADS)

    Mantsch, Paul M.

    2003-02-01

    The Southern Hemisphere site of the Pierre Auger Observatory is now under construction in Argentina by a collaboration of 50 institutions in 16 countries. The objective of the Auger Project is to make a high statistics measurement of cosmic rays above 1019 eV. The observatory will record extensive air showers induced by these cosmic rays incident on the atmosphere. The measurement will include energy, direction and composition of the primary particles. The engineering phase is now complete and full construction has begun. The search for the source of the highest energy cosmic rays is one of the most interesting problems in astrophysics. Following the discovery of the cosmic microwave background, Greisen and, independently, Zatsepin and Kuzmin realized hat this background radiation would make space opaque to cosmic rays of very high energy. Nevertheless over the past 30 years several tens of events were recorded with energies above the Greisen, Zatsepin, Kuzmin (GZK) cutoff (about 5×1019 eV) including a number above 1020 eV. These events present a conundrum. Because of the GZK cut off these super high-energy events must come from nearby, less than about 50 Mpc. In addition the cosmic acceleration mechanism for achieving these energies is very difficult to conceive. Yet, even though particles of these energies are only slightly deflected by galactic and extragalactic magnetic fields, none clearly points back to a source sufficiently violent to a be a candidate source. The Auger Observatory finished its engineering development phase at the end of 2001. The "Engineering Array" consists of 40 surface particle detector stations and two prototype air fluorescence telescopes. The Observatory, when complete, will have a 1600 detector surface array covering 3000 km**2 overlooked by 24 fluorescence telescopes. The Engineering Array has demonstrated that all of the detector systems perform as well or better than expected. Recently the Observatory has recorded a number of

  6. Airborne Arctic Stratospheric Expedition 2: An Overview

    NASA Technical Reports Server (NTRS)

    Anderson, James G.; Toon, Owen B.

    1993-01-01

    The sudden onset of ozone depletion in the antarctic vortex set a precedent for both the time scale and the severity of global change. The Airborne Antarctic Ozone Experiment (AAOE), staged from Punta Arenas, Chile, in 1987, established that CFCs, halons, and methyl bromide, the dominant sources of chlorine and bromine radicals in the stratosphere, control the rate of ozone destruction over the Antarctic; that the vortex is depleted in reactive nitrogen and water vapor; and that diabatic cooling during the antarctic winter leads to subsidence within the vortex core, importing air from higher altitudes and lower latitudes. This last conclusion is based on observed dramatic distortion in the tracer fields, most notably N2O. In 1989, the first Airborne Arctic Stratospheric Expedition (AASE-I), staged from Stavanger, Norway, and using the same aircraft employed for AAOE (the NASA ER-2 and the NASA DC-8), discovered that while NO(x) and to some degree NO(y) were perturbed within the arctic vortex, there was little evidence for desiccation. Under these (in contrast to the antarctic) marginally perturbed conditions, however, Cl0 was found to be dramatically enhanced such that a large fraction of the available (inorganic) chlorine resided in the form of Cl0 and its dimer ClOOCl. This leaves two abiding issues for the northern hemisphere and the mission of the second Airborne Arctic Stratospheric Expedition (AASE-II): (1) Will significant ozone erosion occur within the arctic vortex in the next ten years as chlorine loading in the stratosphere exceeds four parts per billion by volume? and (2) Which mechanisms are responsible for the observed ozone erosion poleward of 30 deg N in the winter/spring northern hemisphere reported in satellite observations?

  7. Airborne Arctic Stratospheric Expedition 2: An overview

    NASA Technical Reports Server (NTRS)

    Anderson, James G.; Toon, Owen B.

    1993-01-01

    The sudden onset of ozone depletion in the antarctic vortex set a precedent for both the time scale and the severity of global change. The Airborne Antarctic Ozone Experiment (AAOE), stages from Punta Arenas, Chile, in 1987, established that CFCs, halons, and methyl bromide, the dominant sources of chlorine and bromide radicals in the stratosphere, control the rate of ozone destruction over the Antarctic; that the vortex is depleted in reactive nitrogen and water vapor; and that diabatic cooling during the antarctic winter leads to subsidence within the vortex core, importing air from higher altitudes and lower latitudes. This last conclusion is based on observed dramatic distortion in the tracer fields, most notably N2O. In 1989, the first Airborne Arctic Stratospheric Expedition (AASE-1), staged from Stavanger, Norway, and using the same aircraft employed for AAOE (the NASA ER-2 and the NASA DC-8), discovered that while NO(x) and to some degree NO(y) were perturbed within the arctic vortex, there was little evidence for desiccation. Under these (in contrast to the antarctic) marginally perturbed conditions, however, ClO was found to be dramatically enhanced such that a large fraction of the available (inorganic) chlorine resided in the form of ClO and its dimer ClOOCl. This leaves two abiding issues for the northern hemisphere and the mission of the second Airborne Arctic Stratospheric Expedition (AASE-2): (1) Will significant ozone erosion occur within the arctic vortex in the next ten years as chlorine loading in the stratosphere exceeds four parts per billion by volume? (2) Which mechanisms are responsible for the observed ozone erosion poleward of 30 deg N in the winter/spring northern hemisphere reported in satellite observations?

  8. Parts Selection for Space Systems - An Overview and Radiation Perspective

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.

    2008-01-01

    This viewgraph presentation describes the selection of electronic parts for aerospace systems from a space radiation perspective. The topics include: 1) The Trade Space Involved with Part Selection; 2) Understanding Risk; 3) Technical/Design Aspects; 4) Programmatic Overview; 5) Radiation Perspective; 6) Reliability Considerations; 7) An Example Ad hoc Battle; and 8) Sources of Radiation Data.

  9. An Overview of NASA Automotive Component Reliability Studies

    NASA Technical Reports Server (NTRS)

    Sampson, Michael J.

    2016-01-01

    The results of NASAs studies into the appropriateness of using US Automotive electronic parts in NASA spaceflight systems will be presented. The first part of the presentation provides an overview of the United States Automotive Electronics Councils AECQ standardization program, the second part provides a summary of the results of NASAs procurement and testing experiences and other lessons learned along with preliminary test results.

  10. An Overview of Oral Health Status, Resources, and Care Delivery.

    ERIC Educational Resources Information Center

    White, B. Alex

    1994-01-01

    An overview of the current oral health status of Americans looks at the epidemiology of oral/dental diseases, rates of use of dental services, and expenditures for dental health care. Substantial progress in improving oral health is seen as are particular challenges resulting from the aging and ethnic diversification of the population. (MSE)

  11. School Motivation and Cultural Context: An Overview of Research.

    ERIC Educational Resources Information Center

    McInerney, Dennis M.

    This paper presents an overview of 15 years of international study designed to determine the nature of motivational beliefs, values and goals held by students from different cultural groups, the comparability of these beliefs, values, and goals with those promoted by classrooms and schools, and the impact individual, cultural/social, peer, family,…

  12. An Overview of "Green School" Development in China in 2001

    ERIC Educational Resources Information Center

    Zhiyan, Jiao; Hongying, Zeng; Xuhong, Song

    2004-01-01

    This article presents an overview of "green school" development in China in 2001. The authors state, that there were improvements in the organization and management of "green schools." And a number of provinces have established environmental education coordination committees or "green school" lead groups. Furthermore, at the local level,…

  13. Indicators of Tuition, Room, and Board Prices: An Overview.

    ERIC Educational Resources Information Center

    Brinkman, Paul

    An overview is presented on one series within a set of higher education indicators being developed at the National Center for Higher Education Management Systems (NCHEMS): a series dealing with the prices of tuition, room, and board. A Laspeyres-type index and a moving average are used to track tuition, room, and board prices for a sample of 2,488…

  14. Information Processing Theory and Learning Disabilities: An Overview.

    ERIC Educational Resources Information Center

    Swanson, H. Lee

    1987-01-01

    The article provides an overview of a special topical issue on information processing as it relates to learning disabilities. Components of information processing theory are described, a model of information processing is presented, and subsequent articles in the special issue are summarized. (JW)

  15. Planning and Control Processes across the Life Span: An Overview.

    ERIC Educational Resources Information Center

    Lachman, Margie E.; Burack, Orah R.

    1993-01-01

    Presents an overview of the topics of planning and control to provide a context for the articles in this issue of the journal. Considers development across the life span, subgroup variations, and correlates. Also explores potential linkages between planning and control. (MM)

  16. Curriculum Reform and "Quality Education" in China: An Overview

    ERIC Educational Resources Information Center

    Dello-Iacovo, Belinda

    2009-01-01

    This paper provides an overview of Chinese government attempts to promote a revised school curriculum reflecting a more holistic approach to education under the banner of "suzhi jiaoyu" ("quality education"), and positions the policies in the Chinese historical, educational, social and economic context. While the push has inspired innovative…

  17. Issue Update: An Overview of the Immigration Reform Act.

    ERIC Educational Resources Information Center

    Kamasaki, Charles; Briceno, Rose

    An overview of the Immigration Reform and Control Act of 1986 summarizes legislative developments prior to passage of the bill, describes major elements of the legislation, discusses the activities of the National Council of La Raza in monitoring implementation of the law, and emphasizes the necessary role of the network of Hispanic…

  18. An overview of flight computer technologies for future NASA

    NASA Technical Reports Server (NTRS)

    Alkalai, L.

    2001-01-01

    In this paper, we present an overview of current developments by several US Government Agencies and associated programs, towards high-performance single board computers for use in space. Three separate projects will be described; two that are based on the Power PC processor, and one based on the Pentium processor.

  19. An Overview Of NASA Automotive Component Reliability Studies

    NASA Technical Reports Server (NTRS)

    Sampson, Michael J.

    2016-01-01

    The results of NASAs studies into the appropriateness of using US Automotive electronic parts in NASA spaceflight systems will be presented. The first part of the presentation provides an overview of the United States Automotive Electronics Councils AECQ standardization program, the second part provides a summary of the results of NASAs procurement and testing experiences and other lessons learned along with preliminary test results.

  20. Advances in water resources assessment with SWAT - an overview

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper introduces a Special Issue containing 12 research articles which present current applications of the Soil and Water Assessment Tool (SWAT) for water resources assessment. Firstly, an overview of selected recently published articles with application of SWAT is given. The articles address ...

  1. EMERGING CONTAMINANTS: AN OVERVIEW OF ON-GOING RESEARCH

    EPA Science Inventory

    This presentation covers an overview of research on emerging contaminants on-going at

    U.S. EPA's National Exposure Research Laboratory in Las Vegas. Due to the

    improvements and sophistication of recent analytical instruments, increasing numbers of

    chemicals a...

  2. Youth Gangs: An Overview. Juvenile Justice Bulletin. Youth Gang Series.

    ERIC Educational Resources Information Center

    Howell, James C.

    1998-01-01

    This bulletin provides an overview of the problems that youth gangs pose. It pinpoints the differences between youth gangs and adult criminal organizations and examines the risk factors that lead to youth gang membership. Some promising strategies being used to curb youth gang involvement are reviewed. The proliferation of youth gangs since 1980…

  3. Effects of ionizing radiation on selected optical materials: An overview

    SciTech Connect

    Wirtenson, G.R.; White, R.H.

    1992-07-30

    This report gives an overview of the effects of ionizing radiation on optical materials that may be used in spacecraft sensors. It introduces the relevant phenomena and indicates were more detailed information can be found. The topics covered include radiation induced absorption in ultraviolet transmitting materials, ordinary optical glasses, cerium stabilized optical glasses, and infrared transmitting materials; bleaching and annealing, and radioluminesence.

  4. Active control of large space structures: An introduction and overview

    NASA Technical Reports Server (NTRS)

    Doane, G. B., III; Tollison, D. K.; Waites, H. B.

    1985-01-01

    An overview of the large space structure (LSS) control system design problem is presented. The LSS is defined as a class of system, and LSS modeling techniques are discussed. Model truncation, control system objectives, current control law design techniques, and particular problem areas are discussed.

  5. An Overview of Discourse Analysis and Its Usefulness in TESOL.

    ERIC Educational Resources Information Center

    Milne, Geraldine Veronica

    This paper provides an overview of discourse analysis from a linguistic point of view, discussing why it is relevant to Teaching English to Speakers of Other Languages (TESOL). It focuses on the following: discourse and discourse analysis; discourse analysis and TESOL; approaches to discourse analysis; systemic functional linguistics; theme and…

  6. Counseling Families of Children with Diabetes Mellitus: An Overview.

    ERIC Educational Resources Information Center

    Yousef, Jamal M. S.

    1995-01-01

    The impact that counseling can have on a family with a child with diabetes mellitus is discussed. The benefits for the child's psychosocial adjustment and development are highlighted. An overview of the challenges a family with a diabetic child faces is provided and the counselor's role in assisting such families is emphasized. (CR)

  7. Bullying in Schools: An Overview. Juvenile Justice Bulletin

    ERIC Educational Resources Information Center

    Seeley, Ken; Tombari, Martin L.; Bennett, Laurie J.; Dunkle, Jason B.

    2011-01-01

    Researchers from the National Center for School Engagement conducted a series of studies to explore the connections between bullying in schools, school attendance and engagement, and academic achievement. This bulletin provides an overview of the studies funded by the Office of Juvenile Justice and Delinquency Prevention (OJJDP), a summary of the…

  8. International Collaboration in Higher Education: An Overview of Critical Issues.

    ERIC Educational Resources Information Center

    Edelson, Paul Jay

    This paper provides an overview of the challenges that impede success in collaboration among U.S. institutions of higher education and foreign institutions. There are problems in many areas, including administrative aspects, regulatory environment, the fiscal situation, and cultural and political factors. In crafting a response strategy, some…

  9. Online Student Services: An Overview of the Provision.

    ERIC Educational Resources Information Center

    McNickle, Cathy

    This paper presents an overview of online student services being used by 19 vocational education and training (VET) and higher education institutions in Australia. Information was gathered though site visits between July and September 2000 about online support services for prospective students, enrolling students, enrolled students, and graduating…

  10. An overview of the Communications Technology Satellite (CTS) project

    NASA Technical Reports Server (NTRS)

    Rapp, W.; Ogden, D.; Wright, D.

    1982-01-01

    The Communications Technology Satellite (CTS) project is reviewed. A technical description of the CTS spacecraft and its cognate hardware and operations is included. A historical treatise of the CTS project is provided. Also presented is an overview of the CTS experiments and demonstrations conducted during the course of the project.

  11. The Law on Reduction In Force: An Overview and Update.

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    This chapter provides an overview of legislation and litigation relating to reduction in force (RIF) with a focus on cases decided since 1980. State statutes continue to be the primary source of the law concerning RIF, so a table is provided for these statutes and their various provisions. These statutes include the dismissla-type, and the less…

  12. An overview of the Japanese solar vehicle industry

    SciTech Connect

    Namasaki, H.

    1994-12-31

    Japan has long had a reputation for holding solar powered vehicle competitions. Many car and boat races are now held there on a regular basis. This year also saw Japan holding the world`s first solar bicycle race. Here, Hideo Namasaki provides SunWorld with an overview of the research and development of Japanese Solar Vehicles.

  13. An overview of the communications technology satellite project: Executive summary

    NASA Technical Reports Server (NTRS)

    Rapp, W.; Ogden, D.; Wright, D.

    1982-01-01

    An overview of the Communications Technology Satellite (CTS) project, a joint venture between NASA and the Canadian Department of Communications is given. A brief technical description of the CTS spacecraft and its cognate hardware and operations, a history of the CTS project, and a list of the CTS experiments and demonstrations conducted during the course of the project are given.

  14. European Design Types for 21st Century Schools: An Overview

    ERIC Educational Resources Information Center

    Rigolon, Alessandro

    2010-01-01

    This article presents a critical overview of European school building design types, based on an analysis of morphologies and spatial layouts. The different design types are evaluated in function of specific didactic and social needs. (Contains 1 figure, 18 footnotes, a bibliography and 2 online resources.)

  15. Natural Language Processing in Game Studies Research: An Overview

    ERIC Educational Resources Information Center

    Zagal, Jose P.; Tomuro, Noriko; Shepitsen, Andriy

    2012-01-01

    Natural language processing (NLP) is a field of computer science and linguistics devoted to creating computer systems that use human (natural) language as input and/or output. The authors propose that NLP can also be used for game studies research. In this article, the authors provide an overview of NLP and describe some research possibilities…

  16. End-of-Life Care: An Overview for Professional Counselors

    ERIC Educational Resources Information Center

    Werth, James L.; Crow, Laura

    2009-01-01

    Although "End-of-Life Care for Terminally Ill Clients" is a section of the "ACA Code of Ethics" (American Counseling Association, 2005), neither the "Code" nor the counseling literature provides much direction for counselors who work with clients who are dying and with the clients' loved ones. The authors provide counselors with an overview of the…

  17. An overview of software safety standards

    SciTech Connect

    Lawrence, J.D.

    1995-10-01

    The writing of standards for software safety is an increasingly important activity. This essay briefly describes the two primary standards-writing organizations, IEEE and IEC, and provides a discussion of some of the more interesting software safety standards.

  18. Seismotectonics context of Tunisia: an overview

    NASA Astrophysics Data System (ADS)

    Bahrouni, Nejib; Bouaziz, Samir; Soumaya, Abdelkader; Ben Ayed, Noureddine; Attafi, Khereddine; Rebai, Noamen

    2013-04-01

    In Tunisia, the seismicity appears low to moderate with magnitude, from Mw 2-5.6. Some earthquakes are regularly experienced by the population and locally cause damage and very significant surface effects as indicated by the data of seismic activity since about 1000 years (in IMN Catalog). On the other hand, the historical sources (Roman then Arabic) give evidence of the strong seismic activities. The study of historical manuscripts showed the existence of strong earthquakes that can be devastating, as was the case of the 410 AD Utica earthquake, that of Kairouan in 854 and also the historic earthquake of 856 that devastated the city of Tunis (Catalogue INM). In Tunisia, the spatial distribution of recent earthquakes epicenters seismically suggests that the main activity occurred in Northwestern Atlas, Southern Atlas, Eastern and Pelagic platform and Tunis surroundings. In addition, we distinguish active zone where late Quaternary surface related deformations (Faults, flexures, uplift) have been evidenced. This work results from a compilation of seismotectonic features, active faults, historical seismic catalog, recent seismic events and geological information collected in Quaternary deposits. We have chosen to represent several types of historical and recent deformations. Numerous data from multiscalar approachs contributed to this work providing good opportunities to clarify the Present day Kinematic model within the North African margin. We propose to treat the active deformation based on observations and new investigations in the field to be able to develop new databases for detailed studies of recent tectonics, seismo-tectonic, historical seismicity, ruptures and surface effects in selected risky areas. The regional stress states reconstructed in recent geological outcrops show a correlation with seismic activity. The mechanism of most Tunisia earthquakes combined with the existing tectonic and structural information and reconstruction of the Quaternary stress

  19. Gravitational Wave Astronomy:. AN Experimental Overview

    NASA Astrophysics Data System (ADS)

    Hammond, Giles

    2011-10-01

    The current worldwide interferometer network comprises detectors in the US (LIGO) and Europe (GEO600 and VIRGO) as well as advanced facilities in Japan (TAMA, CLIO) and Australia (ACIGA). Detectors currently have the sensitivity to detect neutron star binary coalescences out to approximately 15Mpc (the Virgo supercluster). Furthermore the long baseline instruments (LIGO and VIRGO) will shortly be undergoing upgrades which will see their sensitivity increase by an order of magnitude by 2014. These detectors, together with an upgraded GEO detector, should make routine detections and open up the gravitational window on the universe. In the longer term, 3rd generation detectors operating post 2018 will further increase the sensitivity by an additional order of magnitude and will likely feature underground operation at cryogenic temperatures or operation in space.

  20. Electronic document management systems: an overview.

    PubMed

    Kohn, Deborah

    2002-08-01

    For over a decade, most health care information technology (IT) professionals erroneously learned that document imaging, which is one of the many component technologies of an electronic document management system (EDMS), is the only technology of an EDMS. In addition, many health care IT professionals erroneously believed that EDMSs have either a limited role or no place in IT environments. As a result, most health care IT professionals do not understand documents and unstructured data and their value as structured data partners in most aspects of transaction and information processing systems. PMID:12402630

  1. Atopic Dermatitis; Etio-Pathogenesis, An Overview.

    PubMed

    Sehgal, Virendra N; Khurana, Ananta; Mendiratta, Vibhu; Saxena, Deepti; Srivastava, Govind; Aggarwal, Ashok K

    2015-01-01

    Atopic dermatitis is a well-recognized clinical entity, several facets of which continue to be mystified. Accordingly, its etio-pathogenesis is largely elusive. It appears to be an outcome of interplay of several undertones, namely: genetics, maternal factor and inheritance, pregnancy/intrauterine, environmental factors, immune dysregulation, immuno-globulins, role of diet, and infection. Besides, recent innovative breakthroughs consisting of nutritional supplementation, the highlights of which were considered worthwhile to take stock of to define its current status. An endeavor to enlighten the audience has been made for their benefit. PMID:26288398

  2. Atopic Dermatitis; Etio-Pathogenesis, An Overview

    PubMed Central

    Sehgal, Virendra N; Khurana, Ananta; Mendiratta, Vibhu; Saxena, Deepti; Srivastava, Govind; Aggarwal, Ashok K

    2015-01-01

    Atopic dermatitis is a well-recognized clinical entity, several facets of which continue to be mystified. Accordingly, its etio-pathogenesis is largely elusive. It appears to be an outcome of interplay of several undertones, namely: genetics, maternal factor and inheritance, pregnancy/intrauterine, environmental factors, immune dysregulation, immuno-globulins, role of diet, and infection. Besides, recent innovative breakthroughs consisting of nutritional supplementation, the highlights of which were considered worthwhile to take stock of to define its current status. An endeavor to enlighten the audience has been made for their benefit. PMID:26288398

  3. Childhood-Onset Schizophrenia: An Overview

    ERIC Educational Resources Information Center

    Gonthier, Misty; Lyon, Mark A.

    2004-01-01

    Childhood-onset schizophrenia (COS), particularly when diagnosed prior to the age of 13, is considered to be especially rare and severe. This article provides an in-depth look into its symptomatology, general course, long-term functioning, diagnostic criteria, and methods of assessing the disorder. It also includes discussions of the various…

  4. Habituation of vestibular responses: An overview

    NASA Technical Reports Server (NTRS)

    Collins, W. E.

    1973-01-01

    An historical survey of vestibular habituation experiments has been undertaken. Methodological problems are presented briefly, and the influence of arousal on vestibular responses is detailed. Data obtained from animals and from man are treated separately. At least for man, the term habituation may be better defined by a dynamic change in the form of vestibular responses than by a simple response reduction.

  5. An Overview of Adult Education Research.

    ERIC Educational Resources Information Center

    Brunner, Edmund deS.; And Others

    More than 4,000 titles were scrutinized (600 of which are cited) in preparing this report of research in liberal, nonvocational adult education at an early stage in the development of a new discipline within the total universe of education. Wide differences were noted in the amount and quality of research in the various disciplines of the field…

  6. An overview of antithrombotics in ischemic stroke.

    PubMed

    Schweickert, Patricia A; Gaughen, John R; Kreitel, Elizabeth M; Shephard, Timothy J; Solenski, Nina J; Jensen, Mary E

    2016-06-19

    The use of antithrombotic medications is an important component of ischemic stroke treatment and prevention. This article reviews the evidence for best practices for antithrombotic use in stroke with focused discussion on the specific agents used to treat and prevent stroke. PMID:27153001

  7. Safe Computing: An Overview of Viruses.

    ERIC Educational Resources Information Center

    Wodarz, Nan

    2001-01-01

    A computer virus is a program that replicates itself, in conjunction with an additional program that can harm a computer system. Common viruses include boot-sector, macro, companion, overwriting, and multipartite. Viruses can be fast, slow, stealthy, and polymorphic. Anti-virus products are described. (MLH)

  8. Open-Access Electronic Textbooks: An Overview

    ERIC Educational Resources Information Center

    Ovadia, Steven

    2011-01-01

    Given the challenging economic climate in the United States, many academics are looking to open-access electronic textbooks as a way to provide students with traditional textbook content at a more financially advantageous price. Open access refers to "the free and widely available information throughout the World Wide Web. Once an article's author…

  9. An Overview of Online Education in India

    ERIC Educational Resources Information Center

    Ibrar, Mohammad

    2012-01-01

    For over the past years, online education has been quite an option for several learners who have a hard time in going to school campuses due to several reasons such as financial resources or having a hectic schedule. There are several individuals who prefer to continue their higher educational learning through online system. Since, online…

  10. DATA FOR ENVIRONMENTAL MODELING: AN OVERVIEW

    EPA Science Inventory

    The objective of the project described here, entitled Data for Environmental Modeling (D4EM), is the development of a comprehensive set of software tools that allow an environmental model developer to automatically populate model input files with environmental data available from...

  11. An Overview of the Energy Crisis

    ERIC Educational Resources Information Center

    Walters, Edward A.; Wewerka, Eugene M.

    1975-01-01

    Concludes that coal will be the major U.S. energy source in the near future despite the significant problems associated with an increase in coal consumption. Provides advantages and disadvantages for the four major long-term energy sources: nuclear fission, nuclear fusion, geothermal sources, and solar energy. (MLH)

  12. An Overview of Teacher Education in Russia.

    ERIC Educational Resources Information Center

    Herman, William E.

    This paper describes the experience of an educational psychologist who completed a Fulbright Lectureship at Moscow State Pedagogical University in Russia during April and May of 1993. The chaotic situation brought about by the dramatic and rapid changes that have taken place since the collapse of the Soviet Union has resulted in hyperinflation,…

  13. The Borderline Personality--An Adlerian Overview.

    ERIC Educational Resources Information Center

    Rattner, Leo

    The person with a borderline personality is considered to be neither neurotic nor psychotic, but to exist somewhere in between these two diagnostic categories. Psychoanalytic theorists who have researched the phenomenon of the borderline personality have shifted their emphasis away from Freud's instinct psychology and toward an ego psychology…

  14. Relationships across Multiple Settings: An Overview

    ERIC Educational Resources Information Center

    Noam, Gil G.; Fiore, Nina

    2004-01-01

    Educators are witnessing an underlying shift toward recognizing the effects of relationships on development for youth and adults alike in many contexts. Parenting, teaching, mentoring, youth work, out-of-school programming, and therapy have all had shifts in underlying theory, such as attachment models, resilience studies, and feminist psychology,…

  15. Genetic regulations of the biosynthesis of microbial surfactants: an overview.

    PubMed

    Das, Palashpriya; Mukherjee, Soumen; Sen, Ramkrishna

    2008-01-01

    Microbial biosurfactants are surface active metabolites synthesized by microbes growing on a variety of substrates. In spite of having great potential for commercial, therapeutic and environmental applications, industrial level production has not been realized for their low yields and productivities. One vital factor determining their biosynthesis is the genetic makeup of the producer organisms. Studies on molecular genetics and biochemistry of the synthesis of several biosurfactants have revealed the operons, the enzymes and the metabolic pathways required for their extracellular production. Surfactin, a cyclic lipopeptide biosurfactant is a potent antimicrobial agent and is produced as a result of non-ribosomal biosynthesis catalyzed by a large multienzyme peptide synthetase complex called the surfactin synthetase. Pathways for the synthesis of other lipopeptides such as iturin, lichenysin and arthrofactin are also mediated by similar enzyme complexes. These non-ribosomal peptide synthetases (NRPSs) responsible for lipopeptide biosynthesis display a high degree of structural similarity among themselves even from distant microbial species. Plasmid-encoded- rhlA, B, R and I genes of rhl quorum sensing system are required for production of glycolipid biosurfactants by Pseudomonas species. Molecular genetics of biosynthesis of alasan and emulsan by Acinetobacter species and of the fungal biosurfactants such as mannosylerythritol lipids (MEL) and hydrophobins have been deciphered. However, limited genetic information is available about biosynthesis of other biosurfactants such as viscosin, amphisin and putisolvin produced by some strains of Pseudomonas species. Understanding of the genetic regulatory mechanisms would help to develop metabolically engineered hyper-producing strains with better product characteristics and acquired capability of utilizing cheap agro-industrial wastes as substrates. This article thus provides an overview of the role and importance of

  16. European Union vaccine research--an overview.

    PubMed

    Sautter, Jürgen; Olesen, Ole F; Bray, Jeremy; Draghia-Akli, Ruxandra

    2011-09-01

    Recent developments in vaccine research provide new momentum for an important area in health innovation. Particularly interesting are novel DNA vaccine approaches, many of which are already under clinical investigation. The Framework Programmes of the European Union play an important role in supporting collaborative efforts in vaccine research to develop new and better vaccines and bring them to the market. With a timely strategic reorientation towards a sustainable investment in innovation, the current seventh Framework Programme will help to bring large industry and small and medium-sized enterprises (SME) on board and foster partnership between stakeholders. As the first human DNA vaccines progresses through the development pipeline, more and more questions revolve around licensing and regulation and appropriate guidelines are being developed. PMID:21195799

  17. An Overview of Recent Results from CLAS

    SciTech Connect

    Kenneth Hicks

    2011-12-01

    The unique capabilities of the CLAS detector to measure exclusive meson electroproduction off protons, with almost complete coverage of the final hadron phase space, has extended our knowledge of excited baryon structure. Consistent results from Np and Npp final states provide convincing evidence for reliable extraction of N* electrocouplings. Theoretical analyses of these results, using self-consistent dynamical calculations using an internal quark core and an external meson-baryon cloud suggest that meson-baryon dressing amplitudes need to be included. The meson-baryon dressing was already shown to be necessary to get agreement between calculations and data on the D resonance transition magnetic moment at low Q{sup 2}. Similarly, a new measurement of the transition magnetic moment for strange baryons also disagrees with quark models, suggesting the need for meson-baryon dressings. In the near future, the CLAS detector will be replaced with CLAS12, providing new high-precision data.

  18. An overview of ESA cryocooler activities

    NASA Astrophysics Data System (ADS)

    Jewell, C. I.

    1991-12-01

    With a significant number of future cryogenic cooling requirements incompatible with either radiative or cryogen cooling, a program of cryocooler developments which should lead to a range of 'space qualified' cryocoolers being commercially available for future users has been followed. An ESA 80 K 'Oxford type' cooler can presently be considered to be space qualified, while 20 and 4 K coolers are expected to be 'qualified' by 1992. Work is also being undertaken for the development of a 2.5 K cryocooler with 0.3 K as a future goal. The history of the 'Oxfordtype' cooler indicated that the design is based on an excellent pedigree and suggested future work should significantly increase the cryocoolers realm of applications.

  19. Chronic Obstructive Pulmonary Disease: An Overview

    PubMed Central

    Devine, John F.

    2008-01-01

    Chronic obstructive pulmonary disease is a growing healthcare problem that is expected to worsen as the population ages and the worldwide use of tobacco products increases. Smoking cessation is the only effective means of prevention. Employers are in a unique position to help employees stop smoking. During the long asymptomatic phase, lung function nevertheless continues to decline; therefore, many patients seek medical attention only when they are at an advanced stage or when they have experienced an acute exacerbation. To help preserve patients' quality of life and reduce healthcare costs related to this chronic disease, clinicians need to accurately diagnose the condition and appropriately manage patients through the long course of their illness. This article discusses the current approach to patient management. PMID:25126252

  20. The tectonics of Venus: An overview

    NASA Technical Reports Server (NTRS)

    Solomon, Sean C.

    1992-01-01

    While the Pioneer Venus altimeter, Earth-based radar observatories, and the Venera 15-16 orbital imaging radars provided views of large-scale tectonic features on Venus at ever-increasing resolution, the radar images from Magellan constitute an improvement in resolution of at least an order of magnitude over the best previously available. A summary of early Magellan observations of tectonic features on Venus was published, but data available at that time were restricted to the first month of mapping and represented only about 15 percent of the surface of the planet. Magellan images and altimetry are now available for more than 95 percent of the Venus surface. Thus a more global perspective may be taken on the styles and distribution of lithospheric deformation on Venus and their implications for the tectonic history of the planet.